Merge tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git...
[platform/kernel/linux-rpi.git] / security / selinux / hooks.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  NSA Security-Enhanced Linux (SELinux) security module
4  *
5  *  This file contains the SELinux hook function implementations.
6  *
7  *  Authors:  Stephen Smalley, <sds@tycho.nsa.gov>
8  *            Chris Vance, <cvance@nai.com>
9  *            Wayne Salamon, <wsalamon@nai.com>
10  *            James Morris <jmorris@redhat.com>
11  *
12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
14  *                                         Eric Paris <eparis@redhat.com>
15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16  *                          <dgoeddel@trustedcs.com>
17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18  *      Paul Moore <paul@paul-moore.com>
19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
21  *  Copyright (C) 2016 Mellanox Technologies
22  */
23
24 #include <linux/init.h>
25 #include <linux/kd.h>
26 #include <linux/kernel.h>
27 #include <linux/tracehook.h>
28 #include <linux/errno.h>
29 #include <linux/sched/signal.h>
30 #include <linux/sched/task.h>
31 #include <linux/lsm_hooks.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/proc_fs.h>
40 #include <linux/swap.h>
41 #include <linux/spinlock.h>
42 #include <linux/syscalls.h>
43 #include <linux/dcache.h>
44 #include <linux/file.h>
45 #include <linux/fdtable.h>
46 #include <linux/namei.h>
47 #include <linux/mount.h>
48 #include <linux/fs_context.h>
49 #include <linux/fs_parser.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h>             /* for local_port_range[] */
55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
56 #include <net/inet_connection_sock.h>
57 #include <net/net_namespace.h>
58 #include <net/netlabel.h>
59 #include <linux/uaccess.h>
60 #include <asm/ioctls.h>
61 #include <linux/atomic.h>
62 #include <linux/bitops.h>
63 #include <linux/interrupt.h>
64 #include <linux/netdevice.h>    /* for network interface checks */
65 #include <net/netlink.h>
66 #include <linux/tcp.h>
67 #include <linux/udp.h>
68 #include <linux/dccp.h>
69 #include <linux/sctp.h>
70 #include <net/sctp/structs.h>
71 #include <linux/quota.h>
72 #include <linux/un.h>           /* for Unix socket types */
73 #include <net/af_unix.h>        /* for Unix socket types */
74 #include <linux/parser.h>
75 #include <linux/nfs_mount.h>
76 #include <net/ipv6.h>
77 #include <linux/hugetlb.h>
78 #include <linux/personality.h>
79 #include <linux/audit.h>
80 #include <linux/string.h>
81 #include <linux/mutex.h>
82 #include <linux/posix-timers.h>
83 #include <linux/syslog.h>
84 #include <linux/user_namespace.h>
85 #include <linux/export.h>
86 #include <linux/msg.h>
87 #include <linux/shm.h>
88 #include <linux/bpf.h>
89 #include <linux/kernfs.h>
90 #include <linux/stringhash.h>   /* for hashlen_string() */
91 #include <uapi/linux/mount.h>
92 #include <linux/fsnotify.h>
93 #include <linux/fanotify.h>
94
95 #include "avc.h"
96 #include "objsec.h"
97 #include "netif.h"
98 #include "netnode.h"
99 #include "netport.h"
100 #include "ibpkey.h"
101 #include "xfrm.h"
102 #include "netlabel.h"
103 #include "audit.h"
104 #include "avc_ss.h"
105
106 struct selinux_state selinux_state;
107
108 /* SECMARK reference count */
109 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
110
111 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
112 static int selinux_enforcing_boot __initdata;
113
114 static int __init enforcing_setup(char *str)
115 {
116         unsigned long enforcing;
117         if (!kstrtoul(str, 0, &enforcing))
118                 selinux_enforcing_boot = enforcing ? 1 : 0;
119         return 1;
120 }
121 __setup("enforcing=", enforcing_setup);
122 #else
123 #define selinux_enforcing_boot 1
124 #endif
125
126 int selinux_enabled_boot __initdata = 1;
127 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
128 static int __init selinux_enabled_setup(char *str)
129 {
130         unsigned long enabled;
131         if (!kstrtoul(str, 0, &enabled))
132                 selinux_enabled_boot = enabled ? 1 : 0;
133         return 1;
134 }
135 __setup("selinux=", selinux_enabled_setup);
136 #endif
137
138 static unsigned int selinux_checkreqprot_boot =
139         CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
140
141 static int __init checkreqprot_setup(char *str)
142 {
143         unsigned long checkreqprot;
144
145         if (!kstrtoul(str, 0, &checkreqprot)) {
146                 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
147                 if (checkreqprot)
148                         pr_warn("SELinux: checkreqprot set to 1 via kernel parameter.  This is deprecated and will be rejected in a future kernel release.\n");
149         }
150         return 1;
151 }
152 __setup("checkreqprot=", checkreqprot_setup);
153
154 /**
155  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
156  *
157  * Description:
158  * This function checks the SECMARK reference counter to see if any SECMARK
159  * targets are currently configured, if the reference counter is greater than
160  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
161  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
162  * policy capability is enabled, SECMARK is always considered enabled.
163  *
164  */
165 static int selinux_secmark_enabled(void)
166 {
167         return (selinux_policycap_alwaysnetwork() ||
168                 atomic_read(&selinux_secmark_refcount));
169 }
170
171 /**
172  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
173  *
174  * Description:
175  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
176  * (1) if any are enabled or false (0) if neither are enabled.  If the
177  * always_check_network policy capability is enabled, peer labeling
178  * is always considered enabled.
179  *
180  */
181 static int selinux_peerlbl_enabled(void)
182 {
183         return (selinux_policycap_alwaysnetwork() ||
184                 netlbl_enabled() || selinux_xfrm_enabled());
185 }
186
187 static int selinux_netcache_avc_callback(u32 event)
188 {
189         if (event == AVC_CALLBACK_RESET) {
190                 sel_netif_flush();
191                 sel_netnode_flush();
192                 sel_netport_flush();
193                 synchronize_net();
194         }
195         return 0;
196 }
197
198 static int selinux_lsm_notifier_avc_callback(u32 event)
199 {
200         if (event == AVC_CALLBACK_RESET) {
201                 sel_ib_pkey_flush();
202                 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
203         }
204
205         return 0;
206 }
207
208 /*
209  * initialise the security for the init task
210  */
211 static void cred_init_security(void)
212 {
213         struct cred *cred = (struct cred *) current->real_cred;
214         struct task_security_struct *tsec;
215
216         tsec = selinux_cred(cred);
217         tsec->osid = tsec->sid = SECINITSID_KERNEL;
218 }
219
220 /*
221  * get the security ID of a set of credentials
222  */
223 static inline u32 cred_sid(const struct cred *cred)
224 {
225         const struct task_security_struct *tsec;
226
227         tsec = selinux_cred(cred);
228         return tsec->sid;
229 }
230
231 /*
232  * get the objective security ID of a task
233  */
234 static inline u32 task_sid(const struct task_struct *task)
235 {
236         u32 sid;
237
238         rcu_read_lock();
239         sid = cred_sid(__task_cred(task));
240         rcu_read_unlock();
241         return sid;
242 }
243
244 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
245
246 /*
247  * Try reloading inode security labels that have been marked as invalid.  The
248  * @may_sleep parameter indicates when sleeping and thus reloading labels is
249  * allowed; when set to false, returns -ECHILD when the label is
250  * invalid.  The @dentry parameter should be set to a dentry of the inode.
251  */
252 static int __inode_security_revalidate(struct inode *inode,
253                                        struct dentry *dentry,
254                                        bool may_sleep)
255 {
256         struct inode_security_struct *isec = selinux_inode(inode);
257
258         might_sleep_if(may_sleep);
259
260         if (selinux_initialized(&selinux_state) &&
261             isec->initialized != LABEL_INITIALIZED) {
262                 if (!may_sleep)
263                         return -ECHILD;
264
265                 /*
266                  * Try reloading the inode security label.  This will fail if
267                  * @opt_dentry is NULL and no dentry for this inode can be
268                  * found; in that case, continue using the old label.
269                  */
270                 inode_doinit_with_dentry(inode, dentry);
271         }
272         return 0;
273 }
274
275 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
276 {
277         return selinux_inode(inode);
278 }
279
280 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
281 {
282         int error;
283
284         error = __inode_security_revalidate(inode, NULL, !rcu);
285         if (error)
286                 return ERR_PTR(error);
287         return selinux_inode(inode);
288 }
289
290 /*
291  * Get the security label of an inode.
292  */
293 static struct inode_security_struct *inode_security(struct inode *inode)
294 {
295         __inode_security_revalidate(inode, NULL, true);
296         return selinux_inode(inode);
297 }
298
299 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
300 {
301         struct inode *inode = d_backing_inode(dentry);
302
303         return selinux_inode(inode);
304 }
305
306 /*
307  * Get the security label of a dentry's backing inode.
308  */
309 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
310 {
311         struct inode *inode = d_backing_inode(dentry);
312
313         __inode_security_revalidate(inode, dentry, true);
314         return selinux_inode(inode);
315 }
316
317 static void inode_free_security(struct inode *inode)
318 {
319         struct inode_security_struct *isec = selinux_inode(inode);
320         struct superblock_security_struct *sbsec;
321
322         if (!isec)
323                 return;
324         sbsec = inode->i_sb->s_security;
325         /*
326          * As not all inode security structures are in a list, we check for
327          * empty list outside of the lock to make sure that we won't waste
328          * time taking a lock doing nothing.
329          *
330          * The list_del_init() function can be safely called more than once.
331          * It should not be possible for this function to be called with
332          * concurrent list_add(), but for better safety against future changes
333          * in the code, we use list_empty_careful() here.
334          */
335         if (!list_empty_careful(&isec->list)) {
336                 spin_lock(&sbsec->isec_lock);
337                 list_del_init(&isec->list);
338                 spin_unlock(&sbsec->isec_lock);
339         }
340 }
341
342 static void superblock_free_security(struct super_block *sb)
343 {
344         struct superblock_security_struct *sbsec = sb->s_security;
345         sb->s_security = NULL;
346         kfree(sbsec);
347 }
348
349 struct selinux_mnt_opts {
350         const char *fscontext, *context, *rootcontext, *defcontext;
351 };
352
353 static void selinux_free_mnt_opts(void *mnt_opts)
354 {
355         struct selinux_mnt_opts *opts = mnt_opts;
356         kfree(opts->fscontext);
357         kfree(opts->context);
358         kfree(opts->rootcontext);
359         kfree(opts->defcontext);
360         kfree(opts);
361 }
362
363 enum {
364         Opt_error = -1,
365         Opt_context = 0,
366         Opt_defcontext = 1,
367         Opt_fscontext = 2,
368         Opt_rootcontext = 3,
369         Opt_seclabel = 4,
370 };
371
372 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
373 static struct {
374         const char *name;
375         int len;
376         int opt;
377         bool has_arg;
378 } tokens[] = {
379         A(context, true),
380         A(fscontext, true),
381         A(defcontext, true),
382         A(rootcontext, true),
383         A(seclabel, false),
384 };
385 #undef A
386
387 static int match_opt_prefix(char *s, int l, char **arg)
388 {
389         int i;
390
391         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
392                 size_t len = tokens[i].len;
393                 if (len > l || memcmp(s, tokens[i].name, len))
394                         continue;
395                 if (tokens[i].has_arg) {
396                         if (len == l || s[len] != '=')
397                                 continue;
398                         *arg = s + len + 1;
399                 } else if (len != l)
400                         continue;
401                 return tokens[i].opt;
402         }
403         return Opt_error;
404 }
405
406 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
407
408 static int may_context_mount_sb_relabel(u32 sid,
409                         struct superblock_security_struct *sbsec,
410                         const struct cred *cred)
411 {
412         const struct task_security_struct *tsec = selinux_cred(cred);
413         int rc;
414
415         rc = avc_has_perm(&selinux_state,
416                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
417                           FILESYSTEM__RELABELFROM, NULL);
418         if (rc)
419                 return rc;
420
421         rc = avc_has_perm(&selinux_state,
422                           tsec->sid, sid, SECCLASS_FILESYSTEM,
423                           FILESYSTEM__RELABELTO, NULL);
424         return rc;
425 }
426
427 static int may_context_mount_inode_relabel(u32 sid,
428                         struct superblock_security_struct *sbsec,
429                         const struct cred *cred)
430 {
431         const struct task_security_struct *tsec = selinux_cred(cred);
432         int rc;
433         rc = avc_has_perm(&selinux_state,
434                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
435                           FILESYSTEM__RELABELFROM, NULL);
436         if (rc)
437                 return rc;
438
439         rc = avc_has_perm(&selinux_state,
440                           sid, sbsec->sid, SECCLASS_FILESYSTEM,
441                           FILESYSTEM__ASSOCIATE, NULL);
442         return rc;
443 }
444
445 static int selinux_is_genfs_special_handling(struct super_block *sb)
446 {
447         /* Special handling. Genfs but also in-core setxattr handler */
448         return  !strcmp(sb->s_type->name, "sysfs") ||
449                 !strcmp(sb->s_type->name, "pstore") ||
450                 !strcmp(sb->s_type->name, "debugfs") ||
451                 !strcmp(sb->s_type->name, "tracefs") ||
452                 !strcmp(sb->s_type->name, "rootfs") ||
453                 (selinux_policycap_cgroupseclabel() &&
454                  (!strcmp(sb->s_type->name, "cgroup") ||
455                   !strcmp(sb->s_type->name, "cgroup2")));
456 }
457
458 static int selinux_is_sblabel_mnt(struct super_block *sb)
459 {
460         struct superblock_security_struct *sbsec = sb->s_security;
461
462         /*
463          * IMPORTANT: Double-check logic in this function when adding a new
464          * SECURITY_FS_USE_* definition!
465          */
466         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
467
468         switch (sbsec->behavior) {
469         case SECURITY_FS_USE_XATTR:
470         case SECURITY_FS_USE_TRANS:
471         case SECURITY_FS_USE_TASK:
472         case SECURITY_FS_USE_NATIVE:
473                 return 1;
474
475         case SECURITY_FS_USE_GENFS:
476                 return selinux_is_genfs_special_handling(sb);
477
478         /* Never allow relabeling on context mounts */
479         case SECURITY_FS_USE_MNTPOINT:
480         case SECURITY_FS_USE_NONE:
481         default:
482                 return 0;
483         }
484 }
485
486 static int sb_finish_set_opts(struct super_block *sb)
487 {
488         struct superblock_security_struct *sbsec = sb->s_security;
489         struct dentry *root = sb->s_root;
490         struct inode *root_inode = d_backing_inode(root);
491         int rc = 0;
492
493         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
494                 /* Make sure that the xattr handler exists and that no
495                    error other than -ENODATA is returned by getxattr on
496                    the root directory.  -ENODATA is ok, as this may be
497                    the first boot of the SELinux kernel before we have
498                    assigned xattr values to the filesystem. */
499                 if (!(root_inode->i_opflags & IOP_XATTR)) {
500                         pr_warn("SELinux: (dev %s, type %s) has no "
501                                "xattr support\n", sb->s_id, sb->s_type->name);
502                         rc = -EOPNOTSUPP;
503                         goto out;
504                 }
505
506                 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
507                 if (rc < 0 && rc != -ENODATA) {
508                         if (rc == -EOPNOTSUPP)
509                                 pr_warn("SELinux: (dev %s, type "
510                                        "%s) has no security xattr handler\n",
511                                        sb->s_id, sb->s_type->name);
512                         else
513                                 pr_warn("SELinux: (dev %s, type "
514                                        "%s) getxattr errno %d\n", sb->s_id,
515                                        sb->s_type->name, -rc);
516                         goto out;
517                 }
518         }
519
520         sbsec->flags |= SE_SBINITIALIZED;
521
522         /*
523          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
524          * leave the flag untouched because sb_clone_mnt_opts might be handing
525          * us a superblock that needs the flag to be cleared.
526          */
527         if (selinux_is_sblabel_mnt(sb))
528                 sbsec->flags |= SBLABEL_MNT;
529         else
530                 sbsec->flags &= ~SBLABEL_MNT;
531
532         /* Initialize the root inode. */
533         rc = inode_doinit_with_dentry(root_inode, root);
534
535         /* Initialize any other inodes associated with the superblock, e.g.
536            inodes created prior to initial policy load or inodes created
537            during get_sb by a pseudo filesystem that directly
538            populates itself. */
539         spin_lock(&sbsec->isec_lock);
540         while (!list_empty(&sbsec->isec_head)) {
541                 struct inode_security_struct *isec =
542                                 list_first_entry(&sbsec->isec_head,
543                                            struct inode_security_struct, list);
544                 struct inode *inode = isec->inode;
545                 list_del_init(&isec->list);
546                 spin_unlock(&sbsec->isec_lock);
547                 inode = igrab(inode);
548                 if (inode) {
549                         if (!IS_PRIVATE(inode))
550                                 inode_doinit_with_dentry(inode, NULL);
551                         iput(inode);
552                 }
553                 spin_lock(&sbsec->isec_lock);
554         }
555         spin_unlock(&sbsec->isec_lock);
556 out:
557         return rc;
558 }
559
560 static int bad_option(struct superblock_security_struct *sbsec, char flag,
561                       u32 old_sid, u32 new_sid)
562 {
563         char mnt_flags = sbsec->flags & SE_MNTMASK;
564
565         /* check if the old mount command had the same options */
566         if (sbsec->flags & SE_SBINITIALIZED)
567                 if (!(sbsec->flags & flag) ||
568                     (old_sid != new_sid))
569                         return 1;
570
571         /* check if we were passed the same options twice,
572          * aka someone passed context=a,context=b
573          */
574         if (!(sbsec->flags & SE_SBINITIALIZED))
575                 if (mnt_flags & flag)
576                         return 1;
577         return 0;
578 }
579
580 static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
581 {
582         int rc = security_context_str_to_sid(&selinux_state, s,
583                                              sid, GFP_KERNEL);
584         if (rc)
585                 pr_warn("SELinux: security_context_str_to_sid"
586                        "(%s) failed for (dev %s, type %s) errno=%d\n",
587                        s, sb->s_id, sb->s_type->name, rc);
588         return rc;
589 }
590
591 /*
592  * Allow filesystems with binary mount data to explicitly set mount point
593  * labeling information.
594  */
595 static int selinux_set_mnt_opts(struct super_block *sb,
596                                 void *mnt_opts,
597                                 unsigned long kern_flags,
598                                 unsigned long *set_kern_flags)
599 {
600         const struct cred *cred = current_cred();
601         struct superblock_security_struct *sbsec = sb->s_security;
602         struct dentry *root = sbsec->sb->s_root;
603         struct selinux_mnt_opts *opts = mnt_opts;
604         struct inode_security_struct *root_isec;
605         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
606         u32 defcontext_sid = 0;
607         int rc = 0;
608
609         mutex_lock(&sbsec->lock);
610
611         if (!selinux_initialized(&selinux_state)) {
612                 if (!opts) {
613                         /* Defer initialization until selinux_complete_init,
614                            after the initial policy is loaded and the security
615                            server is ready to handle calls. */
616                         goto out;
617                 }
618                 rc = -EINVAL;
619                 pr_warn("SELinux: Unable to set superblock options "
620                         "before the security server is initialized\n");
621                 goto out;
622         }
623         if (kern_flags && !set_kern_flags) {
624                 /* Specifying internal flags without providing a place to
625                  * place the results is not allowed */
626                 rc = -EINVAL;
627                 goto out;
628         }
629
630         /*
631          * Binary mount data FS will come through this function twice.  Once
632          * from an explicit call and once from the generic calls from the vfs.
633          * Since the generic VFS calls will not contain any security mount data
634          * we need to skip the double mount verification.
635          *
636          * This does open a hole in which we will not notice if the first
637          * mount using this sb set explict options and a second mount using
638          * this sb does not set any security options.  (The first options
639          * will be used for both mounts)
640          */
641         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
642             && !opts)
643                 goto out;
644
645         root_isec = backing_inode_security_novalidate(root);
646
647         /*
648          * parse the mount options, check if they are valid sids.
649          * also check if someone is trying to mount the same sb more
650          * than once with different security options.
651          */
652         if (opts) {
653                 if (opts->fscontext) {
654                         rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
655                         if (rc)
656                                 goto out;
657                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
658                                         fscontext_sid))
659                                 goto out_double_mount;
660                         sbsec->flags |= FSCONTEXT_MNT;
661                 }
662                 if (opts->context) {
663                         rc = parse_sid(sb, opts->context, &context_sid);
664                         if (rc)
665                                 goto out;
666                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
667                                         context_sid))
668                                 goto out_double_mount;
669                         sbsec->flags |= CONTEXT_MNT;
670                 }
671                 if (opts->rootcontext) {
672                         rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
673                         if (rc)
674                                 goto out;
675                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
676                                         rootcontext_sid))
677                                 goto out_double_mount;
678                         sbsec->flags |= ROOTCONTEXT_MNT;
679                 }
680                 if (opts->defcontext) {
681                         rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
682                         if (rc)
683                                 goto out;
684                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
685                                         defcontext_sid))
686                                 goto out_double_mount;
687                         sbsec->flags |= DEFCONTEXT_MNT;
688                 }
689         }
690
691         if (sbsec->flags & SE_SBINITIALIZED) {
692                 /* previously mounted with options, but not on this attempt? */
693                 if ((sbsec->flags & SE_MNTMASK) && !opts)
694                         goto out_double_mount;
695                 rc = 0;
696                 goto out;
697         }
698
699         if (strcmp(sb->s_type->name, "proc") == 0)
700                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
701
702         if (!strcmp(sb->s_type->name, "debugfs") ||
703             !strcmp(sb->s_type->name, "tracefs") ||
704             !strcmp(sb->s_type->name, "binder") ||
705             !strcmp(sb->s_type->name, "bpf") ||
706             !strcmp(sb->s_type->name, "pstore"))
707                 sbsec->flags |= SE_SBGENFS;
708
709         if (!strcmp(sb->s_type->name, "sysfs") ||
710             !strcmp(sb->s_type->name, "cgroup") ||
711             !strcmp(sb->s_type->name, "cgroup2"))
712                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
713
714         if (!sbsec->behavior) {
715                 /*
716                  * Determine the labeling behavior to use for this
717                  * filesystem type.
718                  */
719                 rc = security_fs_use(&selinux_state, sb);
720                 if (rc) {
721                         pr_warn("%s: security_fs_use(%s) returned %d\n",
722                                         __func__, sb->s_type->name, rc);
723                         goto out;
724                 }
725         }
726
727         /*
728          * If this is a user namespace mount and the filesystem type is not
729          * explicitly whitelisted, then no contexts are allowed on the command
730          * line and security labels must be ignored.
731          */
732         if (sb->s_user_ns != &init_user_ns &&
733             strcmp(sb->s_type->name, "tmpfs") &&
734             strcmp(sb->s_type->name, "ramfs") &&
735             strcmp(sb->s_type->name, "devpts")) {
736                 if (context_sid || fscontext_sid || rootcontext_sid ||
737                     defcontext_sid) {
738                         rc = -EACCES;
739                         goto out;
740                 }
741                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
742                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
743                         rc = security_transition_sid(&selinux_state,
744                                                      current_sid(),
745                                                      current_sid(),
746                                                      SECCLASS_FILE, NULL,
747                                                      &sbsec->mntpoint_sid);
748                         if (rc)
749                                 goto out;
750                 }
751                 goto out_set_opts;
752         }
753
754         /* sets the context of the superblock for the fs being mounted. */
755         if (fscontext_sid) {
756                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
757                 if (rc)
758                         goto out;
759
760                 sbsec->sid = fscontext_sid;
761         }
762
763         /*
764          * Switch to using mount point labeling behavior.
765          * sets the label used on all file below the mountpoint, and will set
766          * the superblock context if not already set.
767          */
768         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
769                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
770                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
771         }
772
773         if (context_sid) {
774                 if (!fscontext_sid) {
775                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
776                                                           cred);
777                         if (rc)
778                                 goto out;
779                         sbsec->sid = context_sid;
780                 } else {
781                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
782                                                              cred);
783                         if (rc)
784                                 goto out;
785                 }
786                 if (!rootcontext_sid)
787                         rootcontext_sid = context_sid;
788
789                 sbsec->mntpoint_sid = context_sid;
790                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
791         }
792
793         if (rootcontext_sid) {
794                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
795                                                      cred);
796                 if (rc)
797                         goto out;
798
799                 root_isec->sid = rootcontext_sid;
800                 root_isec->initialized = LABEL_INITIALIZED;
801         }
802
803         if (defcontext_sid) {
804                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
805                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
806                         rc = -EINVAL;
807                         pr_warn("SELinux: defcontext option is "
808                                "invalid for this filesystem type\n");
809                         goto out;
810                 }
811
812                 if (defcontext_sid != sbsec->def_sid) {
813                         rc = may_context_mount_inode_relabel(defcontext_sid,
814                                                              sbsec, cred);
815                         if (rc)
816                                 goto out;
817                 }
818
819                 sbsec->def_sid = defcontext_sid;
820         }
821
822 out_set_opts:
823         rc = sb_finish_set_opts(sb);
824 out:
825         mutex_unlock(&sbsec->lock);
826         return rc;
827 out_double_mount:
828         rc = -EINVAL;
829         pr_warn("SELinux: mount invalid.  Same superblock, different "
830                "security settings for (dev %s, type %s)\n", sb->s_id,
831                sb->s_type->name);
832         goto out;
833 }
834
835 static int selinux_cmp_sb_context(const struct super_block *oldsb,
836                                     const struct super_block *newsb)
837 {
838         struct superblock_security_struct *old = oldsb->s_security;
839         struct superblock_security_struct *new = newsb->s_security;
840         char oldflags = old->flags & SE_MNTMASK;
841         char newflags = new->flags & SE_MNTMASK;
842
843         if (oldflags != newflags)
844                 goto mismatch;
845         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
846                 goto mismatch;
847         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
848                 goto mismatch;
849         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
850                 goto mismatch;
851         if (oldflags & ROOTCONTEXT_MNT) {
852                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
853                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
854                 if (oldroot->sid != newroot->sid)
855                         goto mismatch;
856         }
857         return 0;
858 mismatch:
859         pr_warn("SELinux: mount invalid.  Same superblock, "
860                             "different security settings for (dev %s, "
861                             "type %s)\n", newsb->s_id, newsb->s_type->name);
862         return -EBUSY;
863 }
864
865 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
866                                         struct super_block *newsb,
867                                         unsigned long kern_flags,
868                                         unsigned long *set_kern_flags)
869 {
870         int rc = 0;
871         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
872         struct superblock_security_struct *newsbsec = newsb->s_security;
873
874         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
875         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
876         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
877
878         /*
879          * if the parent was able to be mounted it clearly had no special lsm
880          * mount options.  thus we can safely deal with this superblock later
881          */
882         if (!selinux_initialized(&selinux_state))
883                 return 0;
884
885         /*
886          * Specifying internal flags without providing a place to
887          * place the results is not allowed.
888          */
889         if (kern_flags && !set_kern_flags)
890                 return -EINVAL;
891
892         /* how can we clone if the old one wasn't set up?? */
893         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
894
895         /* if fs is reusing a sb, make sure that the contexts match */
896         if (newsbsec->flags & SE_SBINITIALIZED) {
897                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
898                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
899                 return selinux_cmp_sb_context(oldsb, newsb);
900         }
901
902         mutex_lock(&newsbsec->lock);
903
904         newsbsec->flags = oldsbsec->flags;
905
906         newsbsec->sid = oldsbsec->sid;
907         newsbsec->def_sid = oldsbsec->def_sid;
908         newsbsec->behavior = oldsbsec->behavior;
909
910         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
911                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
912                 rc = security_fs_use(&selinux_state, newsb);
913                 if (rc)
914                         goto out;
915         }
916
917         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
918                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
919                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
920         }
921
922         if (set_context) {
923                 u32 sid = oldsbsec->mntpoint_sid;
924
925                 if (!set_fscontext)
926                         newsbsec->sid = sid;
927                 if (!set_rootcontext) {
928                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
929                         newisec->sid = sid;
930                 }
931                 newsbsec->mntpoint_sid = sid;
932         }
933         if (set_rootcontext) {
934                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
935                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
936
937                 newisec->sid = oldisec->sid;
938         }
939
940         sb_finish_set_opts(newsb);
941 out:
942         mutex_unlock(&newsbsec->lock);
943         return rc;
944 }
945
946 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
947 {
948         struct selinux_mnt_opts *opts = *mnt_opts;
949
950         if (token == Opt_seclabel)      /* eaten and completely ignored */
951                 return 0;
952
953         if (!opts) {
954                 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
955                 if (!opts)
956                         return -ENOMEM;
957                 *mnt_opts = opts;
958         }
959         if (!s)
960                 return -ENOMEM;
961         switch (token) {
962         case Opt_context:
963                 if (opts->context || opts->defcontext)
964                         goto Einval;
965                 opts->context = s;
966                 break;
967         case Opt_fscontext:
968                 if (opts->fscontext)
969                         goto Einval;
970                 opts->fscontext = s;
971                 break;
972         case Opt_rootcontext:
973                 if (opts->rootcontext)
974                         goto Einval;
975                 opts->rootcontext = s;
976                 break;
977         case Opt_defcontext:
978                 if (opts->context || opts->defcontext)
979                         goto Einval;
980                 opts->defcontext = s;
981                 break;
982         }
983         return 0;
984 Einval:
985         pr_warn(SEL_MOUNT_FAIL_MSG);
986         return -EINVAL;
987 }
988
989 static int selinux_add_mnt_opt(const char *option, const char *val, int len,
990                                void **mnt_opts)
991 {
992         int token = Opt_error;
993         int rc, i;
994
995         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
996                 if (strcmp(option, tokens[i].name) == 0) {
997                         token = tokens[i].opt;
998                         break;
999                 }
1000         }
1001
1002         if (token == Opt_error)
1003                 return -EINVAL;
1004
1005         if (token != Opt_seclabel) {
1006                 val = kmemdup_nul(val, len, GFP_KERNEL);
1007                 if (!val) {
1008                         rc = -ENOMEM;
1009                         goto free_opt;
1010                 }
1011         }
1012         rc = selinux_add_opt(token, val, mnt_opts);
1013         if (unlikely(rc)) {
1014                 kfree(val);
1015                 goto free_opt;
1016         }
1017         return rc;
1018
1019 free_opt:
1020         if (*mnt_opts) {
1021                 selinux_free_mnt_opts(*mnt_opts);
1022                 *mnt_opts = NULL;
1023         }
1024         return rc;
1025 }
1026
1027 static int show_sid(struct seq_file *m, u32 sid)
1028 {
1029         char *context = NULL;
1030         u32 len;
1031         int rc;
1032
1033         rc = security_sid_to_context(&selinux_state, sid,
1034                                              &context, &len);
1035         if (!rc) {
1036                 bool has_comma = context && strchr(context, ',');
1037
1038                 seq_putc(m, '=');
1039                 if (has_comma)
1040                         seq_putc(m, '\"');
1041                 seq_escape(m, context, "\"\n\\");
1042                 if (has_comma)
1043                         seq_putc(m, '\"');
1044         }
1045         kfree(context);
1046         return rc;
1047 }
1048
1049 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1050 {
1051         struct superblock_security_struct *sbsec = sb->s_security;
1052         int rc;
1053
1054         if (!(sbsec->flags & SE_SBINITIALIZED))
1055                 return 0;
1056
1057         if (!selinux_initialized(&selinux_state))
1058                 return 0;
1059
1060         if (sbsec->flags & FSCONTEXT_MNT) {
1061                 seq_putc(m, ',');
1062                 seq_puts(m, FSCONTEXT_STR);
1063                 rc = show_sid(m, sbsec->sid);
1064                 if (rc)
1065                         return rc;
1066         }
1067         if (sbsec->flags & CONTEXT_MNT) {
1068                 seq_putc(m, ',');
1069                 seq_puts(m, CONTEXT_STR);
1070                 rc = show_sid(m, sbsec->mntpoint_sid);
1071                 if (rc)
1072                         return rc;
1073         }
1074         if (sbsec->flags & DEFCONTEXT_MNT) {
1075                 seq_putc(m, ',');
1076                 seq_puts(m, DEFCONTEXT_STR);
1077                 rc = show_sid(m, sbsec->def_sid);
1078                 if (rc)
1079                         return rc;
1080         }
1081         if (sbsec->flags & ROOTCONTEXT_MNT) {
1082                 struct dentry *root = sbsec->sb->s_root;
1083                 struct inode_security_struct *isec = backing_inode_security(root);
1084                 seq_putc(m, ',');
1085                 seq_puts(m, ROOTCONTEXT_STR);
1086                 rc = show_sid(m, isec->sid);
1087                 if (rc)
1088                         return rc;
1089         }
1090         if (sbsec->flags & SBLABEL_MNT) {
1091                 seq_putc(m, ',');
1092                 seq_puts(m, SECLABEL_STR);
1093         }
1094         return 0;
1095 }
1096
1097 static inline u16 inode_mode_to_security_class(umode_t mode)
1098 {
1099         switch (mode & S_IFMT) {
1100         case S_IFSOCK:
1101                 return SECCLASS_SOCK_FILE;
1102         case S_IFLNK:
1103                 return SECCLASS_LNK_FILE;
1104         case S_IFREG:
1105                 return SECCLASS_FILE;
1106         case S_IFBLK:
1107                 return SECCLASS_BLK_FILE;
1108         case S_IFDIR:
1109                 return SECCLASS_DIR;
1110         case S_IFCHR:
1111                 return SECCLASS_CHR_FILE;
1112         case S_IFIFO:
1113                 return SECCLASS_FIFO_FILE;
1114
1115         }
1116
1117         return SECCLASS_FILE;
1118 }
1119
1120 static inline int default_protocol_stream(int protocol)
1121 {
1122         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1123 }
1124
1125 static inline int default_protocol_dgram(int protocol)
1126 {
1127         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1128 }
1129
1130 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1131 {
1132         int extsockclass = selinux_policycap_extsockclass();
1133
1134         switch (family) {
1135         case PF_UNIX:
1136                 switch (type) {
1137                 case SOCK_STREAM:
1138                 case SOCK_SEQPACKET:
1139                         return SECCLASS_UNIX_STREAM_SOCKET;
1140                 case SOCK_DGRAM:
1141                 case SOCK_RAW:
1142                         return SECCLASS_UNIX_DGRAM_SOCKET;
1143                 }
1144                 break;
1145         case PF_INET:
1146         case PF_INET6:
1147                 switch (type) {
1148                 case SOCK_STREAM:
1149                 case SOCK_SEQPACKET:
1150                         if (default_protocol_stream(protocol))
1151                                 return SECCLASS_TCP_SOCKET;
1152                         else if (extsockclass && protocol == IPPROTO_SCTP)
1153                                 return SECCLASS_SCTP_SOCKET;
1154                         else
1155                                 return SECCLASS_RAWIP_SOCKET;
1156                 case SOCK_DGRAM:
1157                         if (default_protocol_dgram(protocol))
1158                                 return SECCLASS_UDP_SOCKET;
1159                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1160                                                   protocol == IPPROTO_ICMPV6))
1161                                 return SECCLASS_ICMP_SOCKET;
1162                         else
1163                                 return SECCLASS_RAWIP_SOCKET;
1164                 case SOCK_DCCP:
1165                         return SECCLASS_DCCP_SOCKET;
1166                 default:
1167                         return SECCLASS_RAWIP_SOCKET;
1168                 }
1169                 break;
1170         case PF_NETLINK:
1171                 switch (protocol) {
1172                 case NETLINK_ROUTE:
1173                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1174                 case NETLINK_SOCK_DIAG:
1175                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1176                 case NETLINK_NFLOG:
1177                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1178                 case NETLINK_XFRM:
1179                         return SECCLASS_NETLINK_XFRM_SOCKET;
1180                 case NETLINK_SELINUX:
1181                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1182                 case NETLINK_ISCSI:
1183                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1184                 case NETLINK_AUDIT:
1185                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1186                 case NETLINK_FIB_LOOKUP:
1187                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1188                 case NETLINK_CONNECTOR:
1189                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1190                 case NETLINK_NETFILTER:
1191                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1192                 case NETLINK_DNRTMSG:
1193                         return SECCLASS_NETLINK_DNRT_SOCKET;
1194                 case NETLINK_KOBJECT_UEVENT:
1195                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1196                 case NETLINK_GENERIC:
1197                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1198                 case NETLINK_SCSITRANSPORT:
1199                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1200                 case NETLINK_RDMA:
1201                         return SECCLASS_NETLINK_RDMA_SOCKET;
1202                 case NETLINK_CRYPTO:
1203                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1204                 default:
1205                         return SECCLASS_NETLINK_SOCKET;
1206                 }
1207         case PF_PACKET:
1208                 return SECCLASS_PACKET_SOCKET;
1209         case PF_KEY:
1210                 return SECCLASS_KEY_SOCKET;
1211         case PF_APPLETALK:
1212                 return SECCLASS_APPLETALK_SOCKET;
1213         }
1214
1215         if (extsockclass) {
1216                 switch (family) {
1217                 case PF_AX25:
1218                         return SECCLASS_AX25_SOCKET;
1219                 case PF_IPX:
1220                         return SECCLASS_IPX_SOCKET;
1221                 case PF_NETROM:
1222                         return SECCLASS_NETROM_SOCKET;
1223                 case PF_ATMPVC:
1224                         return SECCLASS_ATMPVC_SOCKET;
1225                 case PF_X25:
1226                         return SECCLASS_X25_SOCKET;
1227                 case PF_ROSE:
1228                         return SECCLASS_ROSE_SOCKET;
1229                 case PF_DECnet:
1230                         return SECCLASS_DECNET_SOCKET;
1231                 case PF_ATMSVC:
1232                         return SECCLASS_ATMSVC_SOCKET;
1233                 case PF_RDS:
1234                         return SECCLASS_RDS_SOCKET;
1235                 case PF_IRDA:
1236                         return SECCLASS_IRDA_SOCKET;
1237                 case PF_PPPOX:
1238                         return SECCLASS_PPPOX_SOCKET;
1239                 case PF_LLC:
1240                         return SECCLASS_LLC_SOCKET;
1241                 case PF_CAN:
1242                         return SECCLASS_CAN_SOCKET;
1243                 case PF_TIPC:
1244                         return SECCLASS_TIPC_SOCKET;
1245                 case PF_BLUETOOTH:
1246                         return SECCLASS_BLUETOOTH_SOCKET;
1247                 case PF_IUCV:
1248                         return SECCLASS_IUCV_SOCKET;
1249                 case PF_RXRPC:
1250                         return SECCLASS_RXRPC_SOCKET;
1251                 case PF_ISDN:
1252                         return SECCLASS_ISDN_SOCKET;
1253                 case PF_PHONET:
1254                         return SECCLASS_PHONET_SOCKET;
1255                 case PF_IEEE802154:
1256                         return SECCLASS_IEEE802154_SOCKET;
1257                 case PF_CAIF:
1258                         return SECCLASS_CAIF_SOCKET;
1259                 case PF_ALG:
1260                         return SECCLASS_ALG_SOCKET;
1261                 case PF_NFC:
1262                         return SECCLASS_NFC_SOCKET;
1263                 case PF_VSOCK:
1264                         return SECCLASS_VSOCK_SOCKET;
1265                 case PF_KCM:
1266                         return SECCLASS_KCM_SOCKET;
1267                 case PF_QIPCRTR:
1268                         return SECCLASS_QIPCRTR_SOCKET;
1269                 case PF_SMC:
1270                         return SECCLASS_SMC_SOCKET;
1271                 case PF_XDP:
1272                         return SECCLASS_XDP_SOCKET;
1273 #if PF_MAX > 45
1274 #error New address family defined, please update this function.
1275 #endif
1276                 }
1277         }
1278
1279         return SECCLASS_SOCKET;
1280 }
1281
1282 static int selinux_genfs_get_sid(struct dentry *dentry,
1283                                  u16 tclass,
1284                                  u16 flags,
1285                                  u32 *sid)
1286 {
1287         int rc;
1288         struct super_block *sb = dentry->d_sb;
1289         char *buffer, *path;
1290
1291         buffer = (char *)__get_free_page(GFP_KERNEL);
1292         if (!buffer)
1293                 return -ENOMEM;
1294
1295         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1296         if (IS_ERR(path))
1297                 rc = PTR_ERR(path);
1298         else {
1299                 if (flags & SE_SBPROC) {
1300                         /* each process gets a /proc/PID/ entry. Strip off the
1301                          * PID part to get a valid selinux labeling.
1302                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1303                         while (path[1] >= '0' && path[1] <= '9') {
1304                                 path[1] = '/';
1305                                 path++;
1306                         }
1307                 }
1308                 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1309                                         path, tclass, sid);
1310                 if (rc == -ENOENT) {
1311                         /* No match in policy, mark as unlabeled. */
1312                         *sid = SECINITSID_UNLABELED;
1313                         rc = 0;
1314                 }
1315         }
1316         free_page((unsigned long)buffer);
1317         return rc;
1318 }
1319
1320 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1321                                   u32 def_sid, u32 *sid)
1322 {
1323 #define INITCONTEXTLEN 255
1324         char *context;
1325         unsigned int len;
1326         int rc;
1327
1328         len = INITCONTEXTLEN;
1329         context = kmalloc(len + 1, GFP_NOFS);
1330         if (!context)
1331                 return -ENOMEM;
1332
1333         context[len] = '\0';
1334         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1335         if (rc == -ERANGE) {
1336                 kfree(context);
1337
1338                 /* Need a larger buffer.  Query for the right size. */
1339                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1340                 if (rc < 0)
1341                         return rc;
1342
1343                 len = rc;
1344                 context = kmalloc(len + 1, GFP_NOFS);
1345                 if (!context)
1346                         return -ENOMEM;
1347
1348                 context[len] = '\0';
1349                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1350                                     context, len);
1351         }
1352         if (rc < 0) {
1353                 kfree(context);
1354                 if (rc != -ENODATA) {
1355                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1356                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1357                         return rc;
1358                 }
1359                 *sid = def_sid;
1360                 return 0;
1361         }
1362
1363         rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1364                                              def_sid, GFP_NOFS);
1365         if (rc) {
1366                 char *dev = inode->i_sb->s_id;
1367                 unsigned long ino = inode->i_ino;
1368
1369                 if (rc == -EINVAL) {
1370                         pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1371                                               ino, dev, context);
1372                 } else {
1373                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1374                                 __func__, context, -rc, dev, ino);
1375                 }
1376         }
1377         kfree(context);
1378         return 0;
1379 }
1380
1381 /* The inode's security attributes must be initialized before first use. */
1382 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1383 {
1384         struct superblock_security_struct *sbsec = NULL;
1385         struct inode_security_struct *isec = selinux_inode(inode);
1386         u32 task_sid, sid = 0;
1387         u16 sclass;
1388         struct dentry *dentry;
1389         int rc = 0;
1390
1391         if (isec->initialized == LABEL_INITIALIZED)
1392                 return 0;
1393
1394         spin_lock(&isec->lock);
1395         if (isec->initialized == LABEL_INITIALIZED)
1396                 goto out_unlock;
1397
1398         if (isec->sclass == SECCLASS_FILE)
1399                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1400
1401         sbsec = inode->i_sb->s_security;
1402         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1403                 /* Defer initialization until selinux_complete_init,
1404                    after the initial policy is loaded and the security
1405                    server is ready to handle calls. */
1406                 spin_lock(&sbsec->isec_lock);
1407                 if (list_empty(&isec->list))
1408                         list_add(&isec->list, &sbsec->isec_head);
1409                 spin_unlock(&sbsec->isec_lock);
1410                 goto out_unlock;
1411         }
1412
1413         sclass = isec->sclass;
1414         task_sid = isec->task_sid;
1415         sid = isec->sid;
1416         isec->initialized = LABEL_PENDING;
1417         spin_unlock(&isec->lock);
1418
1419         switch (sbsec->behavior) {
1420         case SECURITY_FS_USE_NATIVE:
1421                 break;
1422         case SECURITY_FS_USE_XATTR:
1423                 if (!(inode->i_opflags & IOP_XATTR)) {
1424                         sid = sbsec->def_sid;
1425                         break;
1426                 }
1427                 /* Need a dentry, since the xattr API requires one.
1428                    Life would be simpler if we could just pass the inode. */
1429                 if (opt_dentry) {
1430                         /* Called from d_instantiate or d_splice_alias. */
1431                         dentry = dget(opt_dentry);
1432                 } else {
1433                         /*
1434                          * Called from selinux_complete_init, try to find a dentry.
1435                          * Some filesystems really want a connected one, so try
1436                          * that first.  We could split SECURITY_FS_USE_XATTR in
1437                          * two, depending upon that...
1438                          */
1439                         dentry = d_find_alias(inode);
1440                         if (!dentry)
1441                                 dentry = d_find_any_alias(inode);
1442                 }
1443                 if (!dentry) {
1444                         /*
1445                          * this is can be hit on boot when a file is accessed
1446                          * before the policy is loaded.  When we load policy we
1447                          * may find inodes that have no dentry on the
1448                          * sbsec->isec_head list.  No reason to complain as these
1449                          * will get fixed up the next time we go through
1450                          * inode_doinit with a dentry, before these inodes could
1451                          * be used again by userspace.
1452                          */
1453                         goto out;
1454                 }
1455
1456                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1457                                             &sid);
1458                 dput(dentry);
1459                 if (rc)
1460                         goto out;
1461                 break;
1462         case SECURITY_FS_USE_TASK:
1463                 sid = task_sid;
1464                 break;
1465         case SECURITY_FS_USE_TRANS:
1466                 /* Default to the fs SID. */
1467                 sid = sbsec->sid;
1468
1469                 /* Try to obtain a transition SID. */
1470                 rc = security_transition_sid(&selinux_state, task_sid, sid,
1471                                              sclass, NULL, &sid);
1472                 if (rc)
1473                         goto out;
1474                 break;
1475         case SECURITY_FS_USE_MNTPOINT:
1476                 sid = sbsec->mntpoint_sid;
1477                 break;
1478         default:
1479                 /* Default to the fs superblock SID. */
1480                 sid = sbsec->sid;
1481
1482                 if ((sbsec->flags & SE_SBGENFS) &&
1483                      (!S_ISLNK(inode->i_mode) ||
1484                       selinux_policycap_genfs_seclabel_symlinks())) {
1485                         /* We must have a dentry to determine the label on
1486                          * procfs inodes */
1487                         if (opt_dentry) {
1488                                 /* Called from d_instantiate or
1489                                  * d_splice_alias. */
1490                                 dentry = dget(opt_dentry);
1491                         } else {
1492                                 /* Called from selinux_complete_init, try to
1493                                  * find a dentry.  Some filesystems really want
1494                                  * a connected one, so try that first.
1495                                  */
1496                                 dentry = d_find_alias(inode);
1497                                 if (!dentry)
1498                                         dentry = d_find_any_alias(inode);
1499                         }
1500                         /*
1501                          * This can be hit on boot when a file is accessed
1502                          * before the policy is loaded.  When we load policy we
1503                          * may find inodes that have no dentry on the
1504                          * sbsec->isec_head list.  No reason to complain as
1505                          * these will get fixed up the next time we go through
1506                          * inode_doinit() with a dentry, before these inodes
1507                          * could be used again by userspace.
1508                          */
1509                         if (!dentry)
1510                                 goto out;
1511                         rc = selinux_genfs_get_sid(dentry, sclass,
1512                                                    sbsec->flags, &sid);
1513                         if (rc) {
1514                                 dput(dentry);
1515                                 goto out;
1516                         }
1517
1518                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1519                             (inode->i_opflags & IOP_XATTR)) {
1520                                 rc = inode_doinit_use_xattr(inode, dentry,
1521                                                             sid, &sid);
1522                                 if (rc) {
1523                                         dput(dentry);
1524                                         goto out;
1525                                 }
1526                         }
1527                         dput(dentry);
1528                 }
1529                 break;
1530         }
1531
1532 out:
1533         spin_lock(&isec->lock);
1534         if (isec->initialized == LABEL_PENDING) {
1535                 if (!sid || rc) {
1536                         isec->initialized = LABEL_INVALID;
1537                         goto out_unlock;
1538                 }
1539
1540                 isec->initialized = LABEL_INITIALIZED;
1541                 isec->sid = sid;
1542         }
1543
1544 out_unlock:
1545         spin_unlock(&isec->lock);
1546         return rc;
1547 }
1548
1549 /* Convert a Linux signal to an access vector. */
1550 static inline u32 signal_to_av(int sig)
1551 {
1552         u32 perm = 0;
1553
1554         switch (sig) {
1555         case SIGCHLD:
1556                 /* Commonly granted from child to parent. */
1557                 perm = PROCESS__SIGCHLD;
1558                 break;
1559         case SIGKILL:
1560                 /* Cannot be caught or ignored */
1561                 perm = PROCESS__SIGKILL;
1562                 break;
1563         case SIGSTOP:
1564                 /* Cannot be caught or ignored */
1565                 perm = PROCESS__SIGSTOP;
1566                 break;
1567         default:
1568                 /* All other signals. */
1569                 perm = PROCESS__SIGNAL;
1570                 break;
1571         }
1572
1573         return perm;
1574 }
1575
1576 #if CAP_LAST_CAP > 63
1577 #error Fix SELinux to handle capabilities > 63.
1578 #endif
1579
1580 /* Check whether a task is allowed to use a capability. */
1581 static int cred_has_capability(const struct cred *cred,
1582                                int cap, unsigned int opts, bool initns)
1583 {
1584         struct common_audit_data ad;
1585         struct av_decision avd;
1586         u16 sclass;
1587         u32 sid = cred_sid(cred);
1588         u32 av = CAP_TO_MASK(cap);
1589         int rc;
1590
1591         ad.type = LSM_AUDIT_DATA_CAP;
1592         ad.u.cap = cap;
1593
1594         switch (CAP_TO_INDEX(cap)) {
1595         case 0:
1596                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1597                 break;
1598         case 1:
1599                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1600                 break;
1601         default:
1602                 pr_err("SELinux:  out of range capability %d\n", cap);
1603                 BUG();
1604                 return -EINVAL;
1605         }
1606
1607         rc = avc_has_perm_noaudit(&selinux_state,
1608                                   sid, sid, sclass, av, 0, &avd);
1609         if (!(opts & CAP_OPT_NOAUDIT)) {
1610                 int rc2 = avc_audit(&selinux_state,
1611                                     sid, sid, sclass, av, &avd, rc, &ad, 0);
1612                 if (rc2)
1613                         return rc2;
1614         }
1615         return rc;
1616 }
1617
1618 /* Check whether a task has a particular permission to an inode.
1619    The 'adp' parameter is optional and allows other audit
1620    data to be passed (e.g. the dentry). */
1621 static int inode_has_perm(const struct cred *cred,
1622                           struct inode *inode,
1623                           u32 perms,
1624                           struct common_audit_data *adp)
1625 {
1626         struct inode_security_struct *isec;
1627         u32 sid;
1628
1629         validate_creds(cred);
1630
1631         if (unlikely(IS_PRIVATE(inode)))
1632                 return 0;
1633
1634         sid = cred_sid(cred);
1635         isec = selinux_inode(inode);
1636
1637         return avc_has_perm(&selinux_state,
1638                             sid, isec->sid, isec->sclass, perms, adp);
1639 }
1640
1641 /* Same as inode_has_perm, but pass explicit audit data containing
1642    the dentry to help the auditing code to more easily generate the
1643    pathname if needed. */
1644 static inline int dentry_has_perm(const struct cred *cred,
1645                                   struct dentry *dentry,
1646                                   u32 av)
1647 {
1648         struct inode *inode = d_backing_inode(dentry);
1649         struct common_audit_data ad;
1650
1651         ad.type = LSM_AUDIT_DATA_DENTRY;
1652         ad.u.dentry = dentry;
1653         __inode_security_revalidate(inode, dentry, true);
1654         return inode_has_perm(cred, inode, av, &ad);
1655 }
1656
1657 /* Same as inode_has_perm, but pass explicit audit data containing
1658    the path to help the auditing code to more easily generate the
1659    pathname if needed. */
1660 static inline int path_has_perm(const struct cred *cred,
1661                                 const struct path *path,
1662                                 u32 av)
1663 {
1664         struct inode *inode = d_backing_inode(path->dentry);
1665         struct common_audit_data ad;
1666
1667         ad.type = LSM_AUDIT_DATA_PATH;
1668         ad.u.path = *path;
1669         __inode_security_revalidate(inode, path->dentry, true);
1670         return inode_has_perm(cred, inode, av, &ad);
1671 }
1672
1673 /* Same as path_has_perm, but uses the inode from the file struct. */
1674 static inline int file_path_has_perm(const struct cred *cred,
1675                                      struct file *file,
1676                                      u32 av)
1677 {
1678         struct common_audit_data ad;
1679
1680         ad.type = LSM_AUDIT_DATA_FILE;
1681         ad.u.file = file;
1682         return inode_has_perm(cred, file_inode(file), av, &ad);
1683 }
1684
1685 #ifdef CONFIG_BPF_SYSCALL
1686 static int bpf_fd_pass(struct file *file, u32 sid);
1687 #endif
1688
1689 /* Check whether a task can use an open file descriptor to
1690    access an inode in a given way.  Check access to the
1691    descriptor itself, and then use dentry_has_perm to
1692    check a particular permission to the file.
1693    Access to the descriptor is implicitly granted if it
1694    has the same SID as the process.  If av is zero, then
1695    access to the file is not checked, e.g. for cases
1696    where only the descriptor is affected like seek. */
1697 static int file_has_perm(const struct cred *cred,
1698                          struct file *file,
1699                          u32 av)
1700 {
1701         struct file_security_struct *fsec = selinux_file(file);
1702         struct inode *inode = file_inode(file);
1703         struct common_audit_data ad;
1704         u32 sid = cred_sid(cred);
1705         int rc;
1706
1707         ad.type = LSM_AUDIT_DATA_FILE;
1708         ad.u.file = file;
1709
1710         if (sid != fsec->sid) {
1711                 rc = avc_has_perm(&selinux_state,
1712                                   sid, fsec->sid,
1713                                   SECCLASS_FD,
1714                                   FD__USE,
1715                                   &ad);
1716                 if (rc)
1717                         goto out;
1718         }
1719
1720 #ifdef CONFIG_BPF_SYSCALL
1721         rc = bpf_fd_pass(file, cred_sid(cred));
1722         if (rc)
1723                 return rc;
1724 #endif
1725
1726         /* av is zero if only checking access to the descriptor. */
1727         rc = 0;
1728         if (av)
1729                 rc = inode_has_perm(cred, inode, av, &ad);
1730
1731 out:
1732         return rc;
1733 }
1734
1735 /*
1736  * Determine the label for an inode that might be unioned.
1737  */
1738 static int
1739 selinux_determine_inode_label(const struct task_security_struct *tsec,
1740                                  struct inode *dir,
1741                                  const struct qstr *name, u16 tclass,
1742                                  u32 *_new_isid)
1743 {
1744         const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1745
1746         if ((sbsec->flags & SE_SBINITIALIZED) &&
1747             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1748                 *_new_isid = sbsec->mntpoint_sid;
1749         } else if ((sbsec->flags & SBLABEL_MNT) &&
1750                    tsec->create_sid) {
1751                 *_new_isid = tsec->create_sid;
1752         } else {
1753                 const struct inode_security_struct *dsec = inode_security(dir);
1754                 return security_transition_sid(&selinux_state, tsec->sid,
1755                                                dsec->sid, tclass,
1756                                                name, _new_isid);
1757         }
1758
1759         return 0;
1760 }
1761
1762 /* Check whether a task can create a file. */
1763 static int may_create(struct inode *dir,
1764                       struct dentry *dentry,
1765                       u16 tclass)
1766 {
1767         const struct task_security_struct *tsec = selinux_cred(current_cred());
1768         struct inode_security_struct *dsec;
1769         struct superblock_security_struct *sbsec;
1770         u32 sid, newsid;
1771         struct common_audit_data ad;
1772         int rc;
1773
1774         dsec = inode_security(dir);
1775         sbsec = dir->i_sb->s_security;
1776
1777         sid = tsec->sid;
1778
1779         ad.type = LSM_AUDIT_DATA_DENTRY;
1780         ad.u.dentry = dentry;
1781
1782         rc = avc_has_perm(&selinux_state,
1783                           sid, dsec->sid, SECCLASS_DIR,
1784                           DIR__ADD_NAME | DIR__SEARCH,
1785                           &ad);
1786         if (rc)
1787                 return rc;
1788
1789         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1790                                            &newsid);
1791         if (rc)
1792                 return rc;
1793
1794         rc = avc_has_perm(&selinux_state,
1795                           sid, newsid, tclass, FILE__CREATE, &ad);
1796         if (rc)
1797                 return rc;
1798
1799         return avc_has_perm(&selinux_state,
1800                             newsid, sbsec->sid,
1801                             SECCLASS_FILESYSTEM,
1802                             FILESYSTEM__ASSOCIATE, &ad);
1803 }
1804
1805 #define MAY_LINK        0
1806 #define MAY_UNLINK      1
1807 #define MAY_RMDIR       2
1808
1809 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1810 static int may_link(struct inode *dir,
1811                     struct dentry *dentry,
1812                     int kind)
1813
1814 {
1815         struct inode_security_struct *dsec, *isec;
1816         struct common_audit_data ad;
1817         u32 sid = current_sid();
1818         u32 av;
1819         int rc;
1820
1821         dsec = inode_security(dir);
1822         isec = backing_inode_security(dentry);
1823
1824         ad.type = LSM_AUDIT_DATA_DENTRY;
1825         ad.u.dentry = dentry;
1826
1827         av = DIR__SEARCH;
1828         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1829         rc = avc_has_perm(&selinux_state,
1830                           sid, dsec->sid, SECCLASS_DIR, av, &ad);
1831         if (rc)
1832                 return rc;
1833
1834         switch (kind) {
1835         case MAY_LINK:
1836                 av = FILE__LINK;
1837                 break;
1838         case MAY_UNLINK:
1839                 av = FILE__UNLINK;
1840                 break;
1841         case MAY_RMDIR:
1842                 av = DIR__RMDIR;
1843                 break;
1844         default:
1845                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1846                         __func__, kind);
1847                 return 0;
1848         }
1849
1850         rc = avc_has_perm(&selinux_state,
1851                           sid, isec->sid, isec->sclass, av, &ad);
1852         return rc;
1853 }
1854
1855 static inline int may_rename(struct inode *old_dir,
1856                              struct dentry *old_dentry,
1857                              struct inode *new_dir,
1858                              struct dentry *new_dentry)
1859 {
1860         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1861         struct common_audit_data ad;
1862         u32 sid = current_sid();
1863         u32 av;
1864         int old_is_dir, new_is_dir;
1865         int rc;
1866
1867         old_dsec = inode_security(old_dir);
1868         old_isec = backing_inode_security(old_dentry);
1869         old_is_dir = d_is_dir(old_dentry);
1870         new_dsec = inode_security(new_dir);
1871
1872         ad.type = LSM_AUDIT_DATA_DENTRY;
1873
1874         ad.u.dentry = old_dentry;
1875         rc = avc_has_perm(&selinux_state,
1876                           sid, old_dsec->sid, SECCLASS_DIR,
1877                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1878         if (rc)
1879                 return rc;
1880         rc = avc_has_perm(&selinux_state,
1881                           sid, old_isec->sid,
1882                           old_isec->sclass, FILE__RENAME, &ad);
1883         if (rc)
1884                 return rc;
1885         if (old_is_dir && new_dir != old_dir) {
1886                 rc = avc_has_perm(&selinux_state,
1887                                   sid, old_isec->sid,
1888                                   old_isec->sclass, DIR__REPARENT, &ad);
1889                 if (rc)
1890                         return rc;
1891         }
1892
1893         ad.u.dentry = new_dentry;
1894         av = DIR__ADD_NAME | DIR__SEARCH;
1895         if (d_is_positive(new_dentry))
1896                 av |= DIR__REMOVE_NAME;
1897         rc = avc_has_perm(&selinux_state,
1898                           sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1899         if (rc)
1900                 return rc;
1901         if (d_is_positive(new_dentry)) {
1902                 new_isec = backing_inode_security(new_dentry);
1903                 new_is_dir = d_is_dir(new_dentry);
1904                 rc = avc_has_perm(&selinux_state,
1905                                   sid, new_isec->sid,
1906                                   new_isec->sclass,
1907                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1908                 if (rc)
1909                         return rc;
1910         }
1911
1912         return 0;
1913 }
1914
1915 /* Check whether a task can perform a filesystem operation. */
1916 static int superblock_has_perm(const struct cred *cred,
1917                                struct super_block *sb,
1918                                u32 perms,
1919                                struct common_audit_data *ad)
1920 {
1921         struct superblock_security_struct *sbsec;
1922         u32 sid = cred_sid(cred);
1923
1924         sbsec = sb->s_security;
1925         return avc_has_perm(&selinux_state,
1926                             sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1927 }
1928
1929 /* Convert a Linux mode and permission mask to an access vector. */
1930 static inline u32 file_mask_to_av(int mode, int mask)
1931 {
1932         u32 av = 0;
1933
1934         if (!S_ISDIR(mode)) {
1935                 if (mask & MAY_EXEC)
1936                         av |= FILE__EXECUTE;
1937                 if (mask & MAY_READ)
1938                         av |= FILE__READ;
1939
1940                 if (mask & MAY_APPEND)
1941                         av |= FILE__APPEND;
1942                 else if (mask & MAY_WRITE)
1943                         av |= FILE__WRITE;
1944
1945         } else {
1946                 if (mask & MAY_EXEC)
1947                         av |= DIR__SEARCH;
1948                 if (mask & MAY_WRITE)
1949                         av |= DIR__WRITE;
1950                 if (mask & MAY_READ)
1951                         av |= DIR__READ;
1952         }
1953
1954         return av;
1955 }
1956
1957 /* Convert a Linux file to an access vector. */
1958 static inline u32 file_to_av(struct file *file)
1959 {
1960         u32 av = 0;
1961
1962         if (file->f_mode & FMODE_READ)
1963                 av |= FILE__READ;
1964         if (file->f_mode & FMODE_WRITE) {
1965                 if (file->f_flags & O_APPEND)
1966                         av |= FILE__APPEND;
1967                 else
1968                         av |= FILE__WRITE;
1969         }
1970         if (!av) {
1971                 /*
1972                  * Special file opened with flags 3 for ioctl-only use.
1973                  */
1974                 av = FILE__IOCTL;
1975         }
1976
1977         return av;
1978 }
1979
1980 /*
1981  * Convert a file to an access vector and include the correct open
1982  * open permission.
1983  */
1984 static inline u32 open_file_to_av(struct file *file)
1985 {
1986         u32 av = file_to_av(file);
1987         struct inode *inode = file_inode(file);
1988
1989         if (selinux_policycap_openperm() &&
1990             inode->i_sb->s_magic != SOCKFS_MAGIC)
1991                 av |= FILE__OPEN;
1992
1993         return av;
1994 }
1995
1996 /* Hook functions begin here. */
1997
1998 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
1999 {
2000         u32 mysid = current_sid();
2001         u32 mgrsid = task_sid(mgr);
2002
2003         return avc_has_perm(&selinux_state,
2004                             mysid, mgrsid, SECCLASS_BINDER,
2005                             BINDER__SET_CONTEXT_MGR, NULL);
2006 }
2007
2008 static int selinux_binder_transaction(struct task_struct *from,
2009                                       struct task_struct *to)
2010 {
2011         u32 mysid = current_sid();
2012         u32 fromsid = task_sid(from);
2013         u32 tosid = task_sid(to);
2014         int rc;
2015
2016         if (mysid != fromsid) {
2017                 rc = avc_has_perm(&selinux_state,
2018                                   mysid, fromsid, SECCLASS_BINDER,
2019                                   BINDER__IMPERSONATE, NULL);
2020                 if (rc)
2021                         return rc;
2022         }
2023
2024         return avc_has_perm(&selinux_state,
2025                             fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2026                             NULL);
2027 }
2028
2029 static int selinux_binder_transfer_binder(struct task_struct *from,
2030                                           struct task_struct *to)
2031 {
2032         u32 fromsid = task_sid(from);
2033         u32 tosid = task_sid(to);
2034
2035         return avc_has_perm(&selinux_state,
2036                             fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2037                             NULL);
2038 }
2039
2040 static int selinux_binder_transfer_file(struct task_struct *from,
2041                                         struct task_struct *to,
2042                                         struct file *file)
2043 {
2044         u32 sid = task_sid(to);
2045         struct file_security_struct *fsec = selinux_file(file);
2046         struct dentry *dentry = file->f_path.dentry;
2047         struct inode_security_struct *isec;
2048         struct common_audit_data ad;
2049         int rc;
2050
2051         ad.type = LSM_AUDIT_DATA_PATH;
2052         ad.u.path = file->f_path;
2053
2054         if (sid != fsec->sid) {
2055                 rc = avc_has_perm(&selinux_state,
2056                                   sid, fsec->sid,
2057                                   SECCLASS_FD,
2058                                   FD__USE,
2059                                   &ad);
2060                 if (rc)
2061                         return rc;
2062         }
2063
2064 #ifdef CONFIG_BPF_SYSCALL
2065         rc = bpf_fd_pass(file, sid);
2066         if (rc)
2067                 return rc;
2068 #endif
2069
2070         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2071                 return 0;
2072
2073         isec = backing_inode_security(dentry);
2074         return avc_has_perm(&selinux_state,
2075                             sid, isec->sid, isec->sclass, file_to_av(file),
2076                             &ad);
2077 }
2078
2079 static int selinux_ptrace_access_check(struct task_struct *child,
2080                                      unsigned int mode)
2081 {
2082         u32 sid = current_sid();
2083         u32 csid = task_sid(child);
2084
2085         if (mode & PTRACE_MODE_READ)
2086                 return avc_has_perm(&selinux_state,
2087                                     sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2088
2089         return avc_has_perm(&selinux_state,
2090                             sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2091 }
2092
2093 static int selinux_ptrace_traceme(struct task_struct *parent)
2094 {
2095         return avc_has_perm(&selinux_state,
2096                             task_sid(parent), current_sid(), SECCLASS_PROCESS,
2097                             PROCESS__PTRACE, NULL);
2098 }
2099
2100 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2101                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2102 {
2103         return avc_has_perm(&selinux_state,
2104                             current_sid(), task_sid(target), SECCLASS_PROCESS,
2105                             PROCESS__GETCAP, NULL);
2106 }
2107
2108 static int selinux_capset(struct cred *new, const struct cred *old,
2109                           const kernel_cap_t *effective,
2110                           const kernel_cap_t *inheritable,
2111                           const kernel_cap_t *permitted)
2112 {
2113         return avc_has_perm(&selinux_state,
2114                             cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2115                             PROCESS__SETCAP, NULL);
2116 }
2117
2118 /*
2119  * (This comment used to live with the selinux_task_setuid hook,
2120  * which was removed).
2121  *
2122  * Since setuid only affects the current process, and since the SELinux
2123  * controls are not based on the Linux identity attributes, SELinux does not
2124  * need to control this operation.  However, SELinux does control the use of
2125  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2126  */
2127
2128 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2129                            int cap, unsigned int opts)
2130 {
2131         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2132 }
2133
2134 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2135 {
2136         const struct cred *cred = current_cred();
2137         int rc = 0;
2138
2139         if (!sb)
2140                 return 0;
2141
2142         switch (cmds) {
2143         case Q_SYNC:
2144         case Q_QUOTAON:
2145         case Q_QUOTAOFF:
2146         case Q_SETINFO:
2147         case Q_SETQUOTA:
2148         case Q_XQUOTAOFF:
2149         case Q_XQUOTAON:
2150         case Q_XSETQLIM:
2151                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2152                 break;
2153         case Q_GETFMT:
2154         case Q_GETINFO:
2155         case Q_GETQUOTA:
2156         case Q_XGETQUOTA:
2157         case Q_XGETQSTAT:
2158         case Q_XGETQSTATV:
2159         case Q_XGETNEXTQUOTA:
2160                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2161                 break;
2162         default:
2163                 rc = 0;  /* let the kernel handle invalid cmds */
2164                 break;
2165         }
2166         return rc;
2167 }
2168
2169 static int selinux_quota_on(struct dentry *dentry)
2170 {
2171         const struct cred *cred = current_cred();
2172
2173         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2174 }
2175
2176 static int selinux_syslog(int type)
2177 {
2178         switch (type) {
2179         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2180         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2181                 return avc_has_perm(&selinux_state,
2182                                     current_sid(), SECINITSID_KERNEL,
2183                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2184         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2185         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2186         /* Set level of messages printed to console */
2187         case SYSLOG_ACTION_CONSOLE_LEVEL:
2188                 return avc_has_perm(&selinux_state,
2189                                     current_sid(), SECINITSID_KERNEL,
2190                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2191                                     NULL);
2192         }
2193         /* All other syslog types */
2194         return avc_has_perm(&selinux_state,
2195                             current_sid(), SECINITSID_KERNEL,
2196                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2197 }
2198
2199 /*
2200  * Check that a process has enough memory to allocate a new virtual
2201  * mapping. 0 means there is enough memory for the allocation to
2202  * succeed and -ENOMEM implies there is not.
2203  *
2204  * Do not audit the selinux permission check, as this is applied to all
2205  * processes that allocate mappings.
2206  */
2207 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2208 {
2209         int rc, cap_sys_admin = 0;
2210
2211         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2212                                  CAP_OPT_NOAUDIT, true);
2213         if (rc == 0)
2214                 cap_sys_admin = 1;
2215
2216         return cap_sys_admin;
2217 }
2218
2219 /* binprm security operations */
2220
2221 static u32 ptrace_parent_sid(void)
2222 {
2223         u32 sid = 0;
2224         struct task_struct *tracer;
2225
2226         rcu_read_lock();
2227         tracer = ptrace_parent(current);
2228         if (tracer)
2229                 sid = task_sid(tracer);
2230         rcu_read_unlock();
2231
2232         return sid;
2233 }
2234
2235 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2236                             const struct task_security_struct *old_tsec,
2237                             const struct task_security_struct *new_tsec)
2238 {
2239         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2240         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2241         int rc;
2242         u32 av;
2243
2244         if (!nnp && !nosuid)
2245                 return 0; /* neither NNP nor nosuid */
2246
2247         if (new_tsec->sid == old_tsec->sid)
2248                 return 0; /* No change in credentials */
2249
2250         /*
2251          * If the policy enables the nnp_nosuid_transition policy capability,
2252          * then we permit transitions under NNP or nosuid if the
2253          * policy allows the corresponding permission between
2254          * the old and new contexts.
2255          */
2256         if (selinux_policycap_nnp_nosuid_transition()) {
2257                 av = 0;
2258                 if (nnp)
2259                         av |= PROCESS2__NNP_TRANSITION;
2260                 if (nosuid)
2261                         av |= PROCESS2__NOSUID_TRANSITION;
2262                 rc = avc_has_perm(&selinux_state,
2263                                   old_tsec->sid, new_tsec->sid,
2264                                   SECCLASS_PROCESS2, av, NULL);
2265                 if (!rc)
2266                         return 0;
2267         }
2268
2269         /*
2270          * We also permit NNP or nosuid transitions to bounded SIDs,
2271          * i.e. SIDs that are guaranteed to only be allowed a subset
2272          * of the permissions of the current SID.
2273          */
2274         rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2275                                          new_tsec->sid);
2276         if (!rc)
2277                 return 0;
2278
2279         /*
2280          * On failure, preserve the errno values for NNP vs nosuid.
2281          * NNP:  Operation not permitted for caller.
2282          * nosuid:  Permission denied to file.
2283          */
2284         if (nnp)
2285                 return -EPERM;
2286         return -EACCES;
2287 }
2288
2289 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2290 {
2291         const struct task_security_struct *old_tsec;
2292         struct task_security_struct *new_tsec;
2293         struct inode_security_struct *isec;
2294         struct common_audit_data ad;
2295         struct inode *inode = file_inode(bprm->file);
2296         int rc;
2297
2298         /* SELinux context only depends on initial program or script and not
2299          * the script interpreter */
2300
2301         old_tsec = selinux_cred(current_cred());
2302         new_tsec = selinux_cred(bprm->cred);
2303         isec = inode_security(inode);
2304
2305         /* Default to the current task SID. */
2306         new_tsec->sid = old_tsec->sid;
2307         new_tsec->osid = old_tsec->sid;
2308
2309         /* Reset fs, key, and sock SIDs on execve. */
2310         new_tsec->create_sid = 0;
2311         new_tsec->keycreate_sid = 0;
2312         new_tsec->sockcreate_sid = 0;
2313
2314         if (old_tsec->exec_sid) {
2315                 new_tsec->sid = old_tsec->exec_sid;
2316                 /* Reset exec SID on execve. */
2317                 new_tsec->exec_sid = 0;
2318
2319                 /* Fail on NNP or nosuid if not an allowed transition. */
2320                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2321                 if (rc)
2322                         return rc;
2323         } else {
2324                 /* Check for a default transition on this program. */
2325                 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2326                                              isec->sid, SECCLASS_PROCESS, NULL,
2327                                              &new_tsec->sid);
2328                 if (rc)
2329                         return rc;
2330
2331                 /*
2332                  * Fallback to old SID on NNP or nosuid if not an allowed
2333                  * transition.
2334                  */
2335                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336                 if (rc)
2337                         new_tsec->sid = old_tsec->sid;
2338         }
2339
2340         ad.type = LSM_AUDIT_DATA_FILE;
2341         ad.u.file = bprm->file;
2342
2343         if (new_tsec->sid == old_tsec->sid) {
2344                 rc = avc_has_perm(&selinux_state,
2345                                   old_tsec->sid, isec->sid,
2346                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2347                 if (rc)
2348                         return rc;
2349         } else {
2350                 /* Check permissions for the transition. */
2351                 rc = avc_has_perm(&selinux_state,
2352                                   old_tsec->sid, new_tsec->sid,
2353                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2354                 if (rc)
2355                         return rc;
2356
2357                 rc = avc_has_perm(&selinux_state,
2358                                   new_tsec->sid, isec->sid,
2359                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2360                 if (rc)
2361                         return rc;
2362
2363                 /* Check for shared state */
2364                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2365                         rc = avc_has_perm(&selinux_state,
2366                                           old_tsec->sid, new_tsec->sid,
2367                                           SECCLASS_PROCESS, PROCESS__SHARE,
2368                                           NULL);
2369                         if (rc)
2370                                 return -EPERM;
2371                 }
2372
2373                 /* Make sure that anyone attempting to ptrace over a task that
2374                  * changes its SID has the appropriate permit */
2375                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2376                         u32 ptsid = ptrace_parent_sid();
2377                         if (ptsid != 0) {
2378                                 rc = avc_has_perm(&selinux_state,
2379                                                   ptsid, new_tsec->sid,
2380                                                   SECCLASS_PROCESS,
2381                                                   PROCESS__PTRACE, NULL);
2382                                 if (rc)
2383                                         return -EPERM;
2384                         }
2385                 }
2386
2387                 /* Clear any possibly unsafe personality bits on exec: */
2388                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2389
2390                 /* Enable secure mode for SIDs transitions unless
2391                    the noatsecure permission is granted between
2392                    the two SIDs, i.e. ahp returns 0. */
2393                 rc = avc_has_perm(&selinux_state,
2394                                   old_tsec->sid, new_tsec->sid,
2395                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2396                                   NULL);
2397                 bprm->secureexec |= !!rc;
2398         }
2399
2400         return 0;
2401 }
2402
2403 static int match_file(const void *p, struct file *file, unsigned fd)
2404 {
2405         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2406 }
2407
2408 /* Derived from fs/exec.c:flush_old_files. */
2409 static inline void flush_unauthorized_files(const struct cred *cred,
2410                                             struct files_struct *files)
2411 {
2412         struct file *file, *devnull = NULL;
2413         struct tty_struct *tty;
2414         int drop_tty = 0;
2415         unsigned n;
2416
2417         tty = get_current_tty();
2418         if (tty) {
2419                 spin_lock(&tty->files_lock);
2420                 if (!list_empty(&tty->tty_files)) {
2421                         struct tty_file_private *file_priv;
2422
2423                         /* Revalidate access to controlling tty.
2424                            Use file_path_has_perm on the tty path directly
2425                            rather than using file_has_perm, as this particular
2426                            open file may belong to another process and we are
2427                            only interested in the inode-based check here. */
2428                         file_priv = list_first_entry(&tty->tty_files,
2429                                                 struct tty_file_private, list);
2430                         file = file_priv->file;
2431                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2432                                 drop_tty = 1;
2433                 }
2434                 spin_unlock(&tty->files_lock);
2435                 tty_kref_put(tty);
2436         }
2437         /* Reset controlling tty. */
2438         if (drop_tty)
2439                 no_tty();
2440
2441         /* Revalidate access to inherited open files. */
2442         n = iterate_fd(files, 0, match_file, cred);
2443         if (!n) /* none found? */
2444                 return;
2445
2446         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2447         if (IS_ERR(devnull))
2448                 devnull = NULL;
2449         /* replace all the matching ones with this */
2450         do {
2451                 replace_fd(n - 1, devnull, 0);
2452         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2453         if (devnull)
2454                 fput(devnull);
2455 }
2456
2457 /*
2458  * Prepare a process for imminent new credential changes due to exec
2459  */
2460 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2461 {
2462         struct task_security_struct *new_tsec;
2463         struct rlimit *rlim, *initrlim;
2464         int rc, i;
2465
2466         new_tsec = selinux_cred(bprm->cred);
2467         if (new_tsec->sid == new_tsec->osid)
2468                 return;
2469
2470         /* Close files for which the new task SID is not authorized. */
2471         flush_unauthorized_files(bprm->cred, current->files);
2472
2473         /* Always clear parent death signal on SID transitions. */
2474         current->pdeath_signal = 0;
2475
2476         /* Check whether the new SID can inherit resource limits from the old
2477          * SID.  If not, reset all soft limits to the lower of the current
2478          * task's hard limit and the init task's soft limit.
2479          *
2480          * Note that the setting of hard limits (even to lower them) can be
2481          * controlled by the setrlimit check.  The inclusion of the init task's
2482          * soft limit into the computation is to avoid resetting soft limits
2483          * higher than the default soft limit for cases where the default is
2484          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2485          */
2486         rc = avc_has_perm(&selinux_state,
2487                           new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2488                           PROCESS__RLIMITINH, NULL);
2489         if (rc) {
2490                 /* protect against do_prlimit() */
2491                 task_lock(current);
2492                 for (i = 0; i < RLIM_NLIMITS; i++) {
2493                         rlim = current->signal->rlim + i;
2494                         initrlim = init_task.signal->rlim + i;
2495                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2496                 }
2497                 task_unlock(current);
2498                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2499                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2500         }
2501 }
2502
2503 /*
2504  * Clean up the process immediately after the installation of new credentials
2505  * due to exec
2506  */
2507 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2508 {
2509         const struct task_security_struct *tsec = selinux_cred(current_cred());
2510         u32 osid, sid;
2511         int rc;
2512
2513         osid = tsec->osid;
2514         sid = tsec->sid;
2515
2516         if (sid == osid)
2517                 return;
2518
2519         /* Check whether the new SID can inherit signal state from the old SID.
2520          * If not, clear itimers to avoid subsequent signal generation and
2521          * flush and unblock signals.
2522          *
2523          * This must occur _after_ the task SID has been updated so that any
2524          * kill done after the flush will be checked against the new SID.
2525          */
2526         rc = avc_has_perm(&selinux_state,
2527                           osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2528         if (rc) {
2529                 clear_itimer();
2530
2531                 spin_lock_irq(&current->sighand->siglock);
2532                 if (!fatal_signal_pending(current)) {
2533                         flush_sigqueue(&current->pending);
2534                         flush_sigqueue(&current->signal->shared_pending);
2535                         flush_signal_handlers(current, 1);
2536                         sigemptyset(&current->blocked);
2537                         recalc_sigpending();
2538                 }
2539                 spin_unlock_irq(&current->sighand->siglock);
2540         }
2541
2542         /* Wake up the parent if it is waiting so that it can recheck
2543          * wait permission to the new task SID. */
2544         read_lock(&tasklist_lock);
2545         __wake_up_parent(current, current->real_parent);
2546         read_unlock(&tasklist_lock);
2547 }
2548
2549 /* superblock security operations */
2550
2551 static int selinux_sb_alloc_security(struct super_block *sb)
2552 {
2553         struct superblock_security_struct *sbsec;
2554
2555         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
2556         if (!sbsec)
2557                 return -ENOMEM;
2558
2559         mutex_init(&sbsec->lock);
2560         INIT_LIST_HEAD(&sbsec->isec_head);
2561         spin_lock_init(&sbsec->isec_lock);
2562         sbsec->sb = sb;
2563         sbsec->sid = SECINITSID_UNLABELED;
2564         sbsec->def_sid = SECINITSID_FILE;
2565         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2566         sb->s_security = sbsec;
2567
2568         return 0;
2569 }
2570
2571 static void selinux_sb_free_security(struct super_block *sb)
2572 {
2573         superblock_free_security(sb);
2574 }
2575
2576 static inline int opt_len(const char *s)
2577 {
2578         bool open_quote = false;
2579         int len;
2580         char c;
2581
2582         for (len = 0; (c = s[len]) != '\0'; len++) {
2583                 if (c == '"')
2584                         open_quote = !open_quote;
2585                 if (c == ',' && !open_quote)
2586                         break;
2587         }
2588         return len;
2589 }
2590
2591 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2592 {
2593         char *from = options;
2594         char *to = options;
2595         bool first = true;
2596         int rc;
2597
2598         while (1) {
2599                 int len = opt_len(from);
2600                 int token;
2601                 char *arg = NULL;
2602
2603                 token = match_opt_prefix(from, len, &arg);
2604
2605                 if (token != Opt_error) {
2606                         char *p, *q;
2607
2608                         /* strip quotes */
2609                         if (arg) {
2610                                 for (p = q = arg; p < from + len; p++) {
2611                                         char c = *p;
2612                                         if (c != '"')
2613                                                 *q++ = c;
2614                                 }
2615                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2616                                 if (!arg) {
2617                                         rc = -ENOMEM;
2618                                         goto free_opt;
2619                                 }
2620                         }
2621                         rc = selinux_add_opt(token, arg, mnt_opts);
2622                         if (unlikely(rc)) {
2623                                 kfree(arg);
2624                                 goto free_opt;
2625                         }
2626                 } else {
2627                         if (!first) {   // copy with preceding comma
2628                                 from--;
2629                                 len++;
2630                         }
2631                         if (to != from)
2632                                 memmove(to, from, len);
2633                         to += len;
2634                         first = false;
2635                 }
2636                 if (!from[len])
2637                         break;
2638                 from += len + 1;
2639         }
2640         *to = '\0';
2641         return 0;
2642
2643 free_opt:
2644         if (*mnt_opts) {
2645                 selinux_free_mnt_opts(*mnt_opts);
2646                 *mnt_opts = NULL;
2647         }
2648         return rc;
2649 }
2650
2651 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2652 {
2653         struct selinux_mnt_opts *opts = mnt_opts;
2654         struct superblock_security_struct *sbsec = sb->s_security;
2655         u32 sid;
2656         int rc;
2657
2658         if (!(sbsec->flags & SE_SBINITIALIZED))
2659                 return 0;
2660
2661         if (!opts)
2662                 return 0;
2663
2664         if (opts->fscontext) {
2665                 rc = parse_sid(sb, opts->fscontext, &sid);
2666                 if (rc)
2667                         return rc;
2668                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2669                         goto out_bad_option;
2670         }
2671         if (opts->context) {
2672                 rc = parse_sid(sb, opts->context, &sid);
2673                 if (rc)
2674                         return rc;
2675                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2676                         goto out_bad_option;
2677         }
2678         if (opts->rootcontext) {
2679                 struct inode_security_struct *root_isec;
2680                 root_isec = backing_inode_security(sb->s_root);
2681                 rc = parse_sid(sb, opts->rootcontext, &sid);
2682                 if (rc)
2683                         return rc;
2684                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2685                         goto out_bad_option;
2686         }
2687         if (opts->defcontext) {
2688                 rc = parse_sid(sb, opts->defcontext, &sid);
2689                 if (rc)
2690                         return rc;
2691                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2692                         goto out_bad_option;
2693         }
2694         return 0;
2695
2696 out_bad_option:
2697         pr_warn("SELinux: unable to change security options "
2698                "during remount (dev %s, type=%s)\n", sb->s_id,
2699                sb->s_type->name);
2700         return -EINVAL;
2701 }
2702
2703 static int selinux_sb_kern_mount(struct super_block *sb)
2704 {
2705         const struct cred *cred = current_cred();
2706         struct common_audit_data ad;
2707
2708         ad.type = LSM_AUDIT_DATA_DENTRY;
2709         ad.u.dentry = sb->s_root;
2710         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2711 }
2712
2713 static int selinux_sb_statfs(struct dentry *dentry)
2714 {
2715         const struct cred *cred = current_cred();
2716         struct common_audit_data ad;
2717
2718         ad.type = LSM_AUDIT_DATA_DENTRY;
2719         ad.u.dentry = dentry->d_sb->s_root;
2720         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2721 }
2722
2723 static int selinux_mount(const char *dev_name,
2724                          const struct path *path,
2725                          const char *type,
2726                          unsigned long flags,
2727                          void *data)
2728 {
2729         const struct cred *cred = current_cred();
2730
2731         if (flags & MS_REMOUNT)
2732                 return superblock_has_perm(cred, path->dentry->d_sb,
2733                                            FILESYSTEM__REMOUNT, NULL);
2734         else
2735                 return path_has_perm(cred, path, FILE__MOUNTON);
2736 }
2737
2738 static int selinux_move_mount(const struct path *from_path,
2739                               const struct path *to_path)
2740 {
2741         const struct cred *cred = current_cred();
2742
2743         return path_has_perm(cred, to_path, FILE__MOUNTON);
2744 }
2745
2746 static int selinux_umount(struct vfsmount *mnt, int flags)
2747 {
2748         const struct cred *cred = current_cred();
2749
2750         return superblock_has_perm(cred, mnt->mnt_sb,
2751                                    FILESYSTEM__UNMOUNT, NULL);
2752 }
2753
2754 static int selinux_fs_context_dup(struct fs_context *fc,
2755                                   struct fs_context *src_fc)
2756 {
2757         const struct selinux_mnt_opts *src = src_fc->security;
2758         struct selinux_mnt_opts *opts;
2759
2760         if (!src)
2761                 return 0;
2762
2763         fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2764         if (!fc->security)
2765                 return -ENOMEM;
2766
2767         opts = fc->security;
2768
2769         if (src->fscontext) {
2770                 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2771                 if (!opts->fscontext)
2772                         return -ENOMEM;
2773         }
2774         if (src->context) {
2775                 opts->context = kstrdup(src->context, GFP_KERNEL);
2776                 if (!opts->context)
2777                         return -ENOMEM;
2778         }
2779         if (src->rootcontext) {
2780                 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2781                 if (!opts->rootcontext)
2782                         return -ENOMEM;
2783         }
2784         if (src->defcontext) {
2785                 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2786                 if (!opts->defcontext)
2787                         return -ENOMEM;
2788         }
2789         return 0;
2790 }
2791
2792 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2793         fsparam_string(CONTEXT_STR,     Opt_context),
2794         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2795         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2796         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2797         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2798         {}
2799 };
2800
2801 static int selinux_fs_context_parse_param(struct fs_context *fc,
2802                                           struct fs_parameter *param)
2803 {
2804         struct fs_parse_result result;
2805         int opt, rc;
2806
2807         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2808         if (opt < 0)
2809                 return opt;
2810
2811         rc = selinux_add_opt(opt, param->string, &fc->security);
2812         if (!rc) {
2813                 param->string = NULL;
2814                 rc = 1;
2815         }
2816         return rc;
2817 }
2818
2819 /* inode security operations */
2820
2821 static int selinux_inode_alloc_security(struct inode *inode)
2822 {
2823         struct inode_security_struct *isec = selinux_inode(inode);
2824         u32 sid = current_sid();
2825
2826         spin_lock_init(&isec->lock);
2827         INIT_LIST_HEAD(&isec->list);
2828         isec->inode = inode;
2829         isec->sid = SECINITSID_UNLABELED;
2830         isec->sclass = SECCLASS_FILE;
2831         isec->task_sid = sid;
2832         isec->initialized = LABEL_INVALID;
2833
2834         return 0;
2835 }
2836
2837 static void selinux_inode_free_security(struct inode *inode)
2838 {
2839         inode_free_security(inode);
2840 }
2841
2842 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2843                                         const struct qstr *name, void **ctx,
2844                                         u32 *ctxlen)
2845 {
2846         u32 newsid;
2847         int rc;
2848
2849         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2850                                            d_inode(dentry->d_parent), name,
2851                                            inode_mode_to_security_class(mode),
2852                                            &newsid);
2853         if (rc)
2854                 return rc;
2855
2856         return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2857                                        ctxlen);
2858 }
2859
2860 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2861                                           struct qstr *name,
2862                                           const struct cred *old,
2863                                           struct cred *new)
2864 {
2865         u32 newsid;
2866         int rc;
2867         struct task_security_struct *tsec;
2868
2869         rc = selinux_determine_inode_label(selinux_cred(old),
2870                                            d_inode(dentry->d_parent), name,
2871                                            inode_mode_to_security_class(mode),
2872                                            &newsid);
2873         if (rc)
2874                 return rc;
2875
2876         tsec = selinux_cred(new);
2877         tsec->create_sid = newsid;
2878         return 0;
2879 }
2880
2881 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2882                                        const struct qstr *qstr,
2883                                        const char **name,
2884                                        void **value, size_t *len)
2885 {
2886         const struct task_security_struct *tsec = selinux_cred(current_cred());
2887         struct superblock_security_struct *sbsec;
2888         u32 newsid, clen;
2889         int rc;
2890         char *context;
2891
2892         sbsec = dir->i_sb->s_security;
2893
2894         newsid = tsec->create_sid;
2895
2896         rc = selinux_determine_inode_label(tsec, dir, qstr,
2897                 inode_mode_to_security_class(inode->i_mode),
2898                 &newsid);
2899         if (rc)
2900                 return rc;
2901
2902         /* Possibly defer initialization to selinux_complete_init. */
2903         if (sbsec->flags & SE_SBINITIALIZED) {
2904                 struct inode_security_struct *isec = selinux_inode(inode);
2905                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2906                 isec->sid = newsid;
2907                 isec->initialized = LABEL_INITIALIZED;
2908         }
2909
2910         if (!selinux_initialized(&selinux_state) ||
2911             !(sbsec->flags & SBLABEL_MNT))
2912                 return -EOPNOTSUPP;
2913
2914         if (name)
2915                 *name = XATTR_SELINUX_SUFFIX;
2916
2917         if (value && len) {
2918                 rc = security_sid_to_context_force(&selinux_state, newsid,
2919                                                    &context, &clen);
2920                 if (rc)
2921                         return rc;
2922                 *value = context;
2923                 *len = clen;
2924         }
2925
2926         return 0;
2927 }
2928
2929 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2930 {
2931         return may_create(dir, dentry, SECCLASS_FILE);
2932 }
2933
2934 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2935 {
2936         return may_link(dir, old_dentry, MAY_LINK);
2937 }
2938
2939 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2940 {
2941         return may_link(dir, dentry, MAY_UNLINK);
2942 }
2943
2944 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2945 {
2946         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2947 }
2948
2949 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2950 {
2951         return may_create(dir, dentry, SECCLASS_DIR);
2952 }
2953
2954 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2955 {
2956         return may_link(dir, dentry, MAY_RMDIR);
2957 }
2958
2959 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2960 {
2961         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2962 }
2963
2964 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2965                                 struct inode *new_inode, struct dentry *new_dentry)
2966 {
2967         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2968 }
2969
2970 static int selinux_inode_readlink(struct dentry *dentry)
2971 {
2972         const struct cred *cred = current_cred();
2973
2974         return dentry_has_perm(cred, dentry, FILE__READ);
2975 }
2976
2977 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2978                                      bool rcu)
2979 {
2980         const struct cred *cred = current_cred();
2981         struct common_audit_data ad;
2982         struct inode_security_struct *isec;
2983         u32 sid;
2984
2985         validate_creds(cred);
2986
2987         ad.type = LSM_AUDIT_DATA_DENTRY;
2988         ad.u.dentry = dentry;
2989         sid = cred_sid(cred);
2990         isec = inode_security_rcu(inode, rcu);
2991         if (IS_ERR(isec))
2992                 return PTR_ERR(isec);
2993
2994         return avc_has_perm_flags(&selinux_state,
2995                                   sid, isec->sid, isec->sclass, FILE__READ, &ad,
2996                                   rcu ? MAY_NOT_BLOCK : 0);
2997 }
2998
2999 static noinline int audit_inode_permission(struct inode *inode,
3000                                            u32 perms, u32 audited, u32 denied,
3001                                            int result)
3002 {
3003         struct common_audit_data ad;
3004         struct inode_security_struct *isec = selinux_inode(inode);
3005         int rc;
3006
3007         ad.type = LSM_AUDIT_DATA_INODE;
3008         ad.u.inode = inode;
3009
3010         rc = slow_avc_audit(&selinux_state,
3011                             current_sid(), isec->sid, isec->sclass, perms,
3012                             audited, denied, result, &ad);
3013         if (rc)
3014                 return rc;
3015         return 0;
3016 }
3017
3018 static int selinux_inode_permission(struct inode *inode, int mask)
3019 {
3020         const struct cred *cred = current_cred();
3021         u32 perms;
3022         bool from_access;
3023         bool no_block = mask & MAY_NOT_BLOCK;
3024         struct inode_security_struct *isec;
3025         u32 sid;
3026         struct av_decision avd;
3027         int rc, rc2;
3028         u32 audited, denied;
3029
3030         from_access = mask & MAY_ACCESS;
3031         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3032
3033         /* No permission to check.  Existence test. */
3034         if (!mask)
3035                 return 0;
3036
3037         validate_creds(cred);
3038
3039         if (unlikely(IS_PRIVATE(inode)))
3040                 return 0;
3041
3042         perms = file_mask_to_av(inode->i_mode, mask);
3043
3044         sid = cred_sid(cred);
3045         isec = inode_security_rcu(inode, no_block);
3046         if (IS_ERR(isec))
3047                 return PTR_ERR(isec);
3048
3049         rc = avc_has_perm_noaudit(&selinux_state,
3050                                   sid, isec->sid, isec->sclass, perms,
3051                                   no_block ? AVC_NONBLOCKING : 0,
3052                                   &avd);
3053         audited = avc_audit_required(perms, &avd, rc,
3054                                      from_access ? FILE__AUDIT_ACCESS : 0,
3055                                      &denied);
3056         if (likely(!audited))
3057                 return rc;
3058
3059         /* fall back to ref-walk if we have to generate audit */
3060         if (no_block)
3061                 return -ECHILD;
3062
3063         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3064         if (rc2)
3065                 return rc2;
3066         return rc;
3067 }
3068
3069 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3070 {
3071         const struct cred *cred = current_cred();
3072         struct inode *inode = d_backing_inode(dentry);
3073         unsigned int ia_valid = iattr->ia_valid;
3074         __u32 av = FILE__WRITE;
3075
3076         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3077         if (ia_valid & ATTR_FORCE) {
3078                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3079                               ATTR_FORCE);
3080                 if (!ia_valid)
3081                         return 0;
3082         }
3083
3084         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3085                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3086                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3087
3088         if (selinux_policycap_openperm() &&
3089             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3090             (ia_valid & ATTR_SIZE) &&
3091             !(ia_valid & ATTR_FILE))
3092                 av |= FILE__OPEN;
3093
3094         return dentry_has_perm(cred, dentry, av);
3095 }
3096
3097 static int selinux_inode_getattr(const struct path *path)
3098 {
3099         return path_has_perm(current_cred(), path, FILE__GETATTR);
3100 }
3101
3102 static bool has_cap_mac_admin(bool audit)
3103 {
3104         const struct cred *cred = current_cred();
3105         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3106
3107         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3108                 return false;
3109         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3110                 return false;
3111         return true;
3112 }
3113
3114 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115                                   const void *value, size_t size, int flags)
3116 {
3117         struct inode *inode = d_backing_inode(dentry);
3118         struct inode_security_struct *isec;
3119         struct superblock_security_struct *sbsec;
3120         struct common_audit_data ad;
3121         u32 newsid, sid = current_sid();
3122         int rc = 0;
3123
3124         if (strcmp(name, XATTR_NAME_SELINUX)) {
3125                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3126                 if (rc)
3127                         return rc;
3128
3129                 /* Not an attribute we recognize, so just check the
3130                    ordinary setattr permission. */
3131                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3132         }
3133
3134         if (!selinux_initialized(&selinux_state))
3135                 return (inode_owner_or_capable(inode) ? 0 : -EPERM);
3136
3137         sbsec = inode->i_sb->s_security;
3138         if (!(sbsec->flags & SBLABEL_MNT))
3139                 return -EOPNOTSUPP;
3140
3141         if (!inode_owner_or_capable(inode))
3142                 return -EPERM;
3143
3144         ad.type = LSM_AUDIT_DATA_DENTRY;
3145         ad.u.dentry = dentry;
3146
3147         isec = backing_inode_security(dentry);
3148         rc = avc_has_perm(&selinux_state,
3149                           sid, isec->sid, isec->sclass,
3150                           FILE__RELABELFROM, &ad);
3151         if (rc)
3152                 return rc;
3153
3154         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3155                                      GFP_KERNEL);
3156         if (rc == -EINVAL) {
3157                 if (!has_cap_mac_admin(true)) {
3158                         struct audit_buffer *ab;
3159                         size_t audit_size;
3160
3161                         /* We strip a nul only if it is at the end, otherwise the
3162                          * context contains a nul and we should audit that */
3163                         if (value) {
3164                                 const char *str = value;
3165
3166                                 if (str[size - 1] == '\0')
3167                                         audit_size = size - 1;
3168                                 else
3169                                         audit_size = size;
3170                         } else {
3171                                 audit_size = 0;
3172                         }
3173                         ab = audit_log_start(audit_context(),
3174                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3175                         audit_log_format(ab, "op=setxattr invalid_context=");
3176                         audit_log_n_untrustedstring(ab, value, audit_size);
3177                         audit_log_end(ab);
3178
3179                         return rc;
3180                 }
3181                 rc = security_context_to_sid_force(&selinux_state, value,
3182                                                    size, &newsid);
3183         }
3184         if (rc)
3185                 return rc;
3186
3187         rc = avc_has_perm(&selinux_state,
3188                           sid, newsid, isec->sclass,
3189                           FILE__RELABELTO, &ad);
3190         if (rc)
3191                 return rc;
3192
3193         rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3194                                           sid, isec->sclass);
3195         if (rc)
3196                 return rc;
3197
3198         return avc_has_perm(&selinux_state,
3199                             newsid,
3200                             sbsec->sid,
3201                             SECCLASS_FILESYSTEM,
3202                             FILESYSTEM__ASSOCIATE,
3203                             &ad);
3204 }
3205
3206 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3207                                         const void *value, size_t size,
3208                                         int flags)
3209 {
3210         struct inode *inode = d_backing_inode(dentry);
3211         struct inode_security_struct *isec;
3212         u32 newsid;
3213         int rc;
3214
3215         if (strcmp(name, XATTR_NAME_SELINUX)) {
3216                 /* Not an attribute we recognize, so nothing to do. */
3217                 return;
3218         }
3219
3220         if (!selinux_initialized(&selinux_state)) {
3221                 /* If we haven't even been initialized, then we can't validate
3222                  * against a policy, so leave the label as invalid. It may
3223                  * resolve to a valid label on the next revalidation try if
3224                  * we've since initialized.
3225                  */
3226                 return;
3227         }
3228
3229         rc = security_context_to_sid_force(&selinux_state, value, size,
3230                                            &newsid);
3231         if (rc) {
3232                 pr_err("SELinux:  unable to map context to SID"
3233                        "for (%s, %lu), rc=%d\n",
3234                        inode->i_sb->s_id, inode->i_ino, -rc);
3235                 return;
3236         }
3237
3238         isec = backing_inode_security(dentry);
3239         spin_lock(&isec->lock);
3240         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3241         isec->sid = newsid;
3242         isec->initialized = LABEL_INITIALIZED;
3243         spin_unlock(&isec->lock);
3244
3245         return;
3246 }
3247
3248 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3249 {
3250         const struct cred *cred = current_cred();
3251
3252         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3253 }
3254
3255 static int selinux_inode_listxattr(struct dentry *dentry)
3256 {
3257         const struct cred *cred = current_cred();
3258
3259         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3260 }
3261
3262 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3263 {
3264         if (strcmp(name, XATTR_NAME_SELINUX)) {
3265                 int rc = cap_inode_removexattr(dentry, name);
3266                 if (rc)
3267                         return rc;
3268
3269                 /* Not an attribute we recognize, so just check the
3270                    ordinary setattr permission. */
3271                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3272         }
3273
3274         /* No one is allowed to remove a SELinux security label.
3275            You can change the label, but all data must be labeled. */
3276         return -EACCES;
3277 }
3278
3279 static int selinux_path_notify(const struct path *path, u64 mask,
3280                                                 unsigned int obj_type)
3281 {
3282         int ret;
3283         u32 perm;
3284
3285         struct common_audit_data ad;
3286
3287         ad.type = LSM_AUDIT_DATA_PATH;
3288         ad.u.path = *path;
3289
3290         /*
3291          * Set permission needed based on the type of mark being set.
3292          * Performs an additional check for sb watches.
3293          */
3294         switch (obj_type) {
3295         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3296                 perm = FILE__WATCH_MOUNT;
3297                 break;
3298         case FSNOTIFY_OBJ_TYPE_SB:
3299                 perm = FILE__WATCH_SB;
3300                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3301                                                 FILESYSTEM__WATCH, &ad);
3302                 if (ret)
3303                         return ret;
3304                 break;
3305         case FSNOTIFY_OBJ_TYPE_INODE:
3306                 perm = FILE__WATCH;
3307                 break;
3308         default:
3309                 return -EINVAL;
3310         }
3311
3312         /* blocking watches require the file:watch_with_perm permission */
3313         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3314                 perm |= FILE__WATCH_WITH_PERM;
3315
3316         /* watches on read-like events need the file:watch_reads permission */
3317         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3318                 perm |= FILE__WATCH_READS;
3319
3320         return path_has_perm(current_cred(), path, perm);
3321 }
3322
3323 /*
3324  * Copy the inode security context value to the user.
3325  *
3326  * Permission check is handled by selinux_inode_getxattr hook.
3327  */
3328 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3329 {
3330         u32 size;
3331         int error;
3332         char *context = NULL;
3333         struct inode_security_struct *isec;
3334
3335         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3336                 return -EOPNOTSUPP;
3337
3338         /*
3339          * If the caller has CAP_MAC_ADMIN, then get the raw context
3340          * value even if it is not defined by current policy; otherwise,
3341          * use the in-core value under current policy.
3342          * Use the non-auditing forms of the permission checks since
3343          * getxattr may be called by unprivileged processes commonly
3344          * and lack of permission just means that we fall back to the
3345          * in-core context value, not a denial.
3346          */
3347         isec = inode_security(inode);
3348         if (has_cap_mac_admin(false))
3349                 error = security_sid_to_context_force(&selinux_state,
3350                                                       isec->sid, &context,
3351                                                       &size);
3352         else
3353                 error = security_sid_to_context(&selinux_state, isec->sid,
3354                                                 &context, &size);
3355         if (error)
3356                 return error;
3357         error = size;
3358         if (alloc) {
3359                 *buffer = context;
3360                 goto out_nofree;
3361         }
3362         kfree(context);
3363 out_nofree:
3364         return error;
3365 }
3366
3367 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3368                                      const void *value, size_t size, int flags)
3369 {
3370         struct inode_security_struct *isec = inode_security_novalidate(inode);
3371         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3372         u32 newsid;
3373         int rc;
3374
3375         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3376                 return -EOPNOTSUPP;
3377
3378         if (!(sbsec->flags & SBLABEL_MNT))
3379                 return -EOPNOTSUPP;
3380
3381         if (!value || !size)
3382                 return -EACCES;
3383
3384         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3385                                      GFP_KERNEL);
3386         if (rc)
3387                 return rc;
3388
3389         spin_lock(&isec->lock);
3390         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3391         isec->sid = newsid;
3392         isec->initialized = LABEL_INITIALIZED;
3393         spin_unlock(&isec->lock);
3394         return 0;
3395 }
3396
3397 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3398 {
3399         const int len = sizeof(XATTR_NAME_SELINUX);
3400         if (buffer && len <= buffer_size)
3401                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3402         return len;
3403 }
3404
3405 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3406 {
3407         struct inode_security_struct *isec = inode_security_novalidate(inode);
3408         *secid = isec->sid;
3409 }
3410
3411 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3412 {
3413         u32 sid;
3414         struct task_security_struct *tsec;
3415         struct cred *new_creds = *new;
3416
3417         if (new_creds == NULL) {
3418                 new_creds = prepare_creds();
3419                 if (!new_creds)
3420                         return -ENOMEM;
3421         }
3422
3423         tsec = selinux_cred(new_creds);
3424         /* Get label from overlay inode and set it in create_sid */
3425         selinux_inode_getsecid(d_inode(src), &sid);
3426         tsec->create_sid = sid;
3427         *new = new_creds;
3428         return 0;
3429 }
3430
3431 static int selinux_inode_copy_up_xattr(const char *name)
3432 {
3433         /* The copy_up hook above sets the initial context on an inode, but we
3434          * don't then want to overwrite it by blindly copying all the lower
3435          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3436          */
3437         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3438                 return 1; /* Discard */
3439         /*
3440          * Any other attribute apart from SELINUX is not claimed, supported
3441          * by selinux.
3442          */
3443         return -EOPNOTSUPP;
3444 }
3445
3446 /* kernfs node operations */
3447
3448 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3449                                         struct kernfs_node *kn)
3450 {
3451         const struct task_security_struct *tsec = selinux_cred(current_cred());
3452         u32 parent_sid, newsid, clen;
3453         int rc;
3454         char *context;
3455
3456         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3457         if (rc == -ENODATA)
3458                 return 0;
3459         else if (rc < 0)
3460                 return rc;
3461
3462         clen = (u32)rc;
3463         context = kmalloc(clen, GFP_KERNEL);
3464         if (!context)
3465                 return -ENOMEM;
3466
3467         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3468         if (rc < 0) {
3469                 kfree(context);
3470                 return rc;
3471         }
3472
3473         rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3474                                      GFP_KERNEL);
3475         kfree(context);
3476         if (rc)
3477                 return rc;
3478
3479         if (tsec->create_sid) {
3480                 newsid = tsec->create_sid;
3481         } else {
3482                 u16 secclass = inode_mode_to_security_class(kn->mode);
3483                 struct qstr q;
3484
3485                 q.name = kn->name;
3486                 q.hash_len = hashlen_string(kn_dir, kn->name);
3487
3488                 rc = security_transition_sid(&selinux_state, tsec->sid,
3489                                              parent_sid, secclass, &q,
3490                                              &newsid);
3491                 if (rc)
3492                         return rc;
3493         }
3494
3495         rc = security_sid_to_context_force(&selinux_state, newsid,
3496                                            &context, &clen);
3497         if (rc)
3498                 return rc;
3499
3500         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3501                               XATTR_CREATE);
3502         kfree(context);
3503         return rc;
3504 }
3505
3506
3507 /* file security operations */
3508
3509 static int selinux_revalidate_file_permission(struct file *file, int mask)
3510 {
3511         const struct cred *cred = current_cred();
3512         struct inode *inode = file_inode(file);
3513
3514         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3515         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3516                 mask |= MAY_APPEND;
3517
3518         return file_has_perm(cred, file,
3519                              file_mask_to_av(inode->i_mode, mask));
3520 }
3521
3522 static int selinux_file_permission(struct file *file, int mask)
3523 {
3524         struct inode *inode = file_inode(file);
3525         struct file_security_struct *fsec = selinux_file(file);
3526         struct inode_security_struct *isec;
3527         u32 sid = current_sid();
3528
3529         if (!mask)
3530                 /* No permission to check.  Existence test. */
3531                 return 0;
3532
3533         isec = inode_security(inode);
3534         if (sid == fsec->sid && fsec->isid == isec->sid &&
3535             fsec->pseqno == avc_policy_seqno(&selinux_state))
3536                 /* No change since file_open check. */
3537                 return 0;
3538
3539         return selinux_revalidate_file_permission(file, mask);
3540 }
3541
3542 static int selinux_file_alloc_security(struct file *file)
3543 {
3544         struct file_security_struct *fsec = selinux_file(file);
3545         u32 sid = current_sid();
3546
3547         fsec->sid = sid;
3548         fsec->fown_sid = sid;
3549
3550         return 0;
3551 }
3552
3553 /*
3554  * Check whether a task has the ioctl permission and cmd
3555  * operation to an inode.
3556  */
3557 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3558                 u32 requested, u16 cmd)
3559 {
3560         struct common_audit_data ad;
3561         struct file_security_struct *fsec = selinux_file(file);
3562         struct inode *inode = file_inode(file);
3563         struct inode_security_struct *isec;
3564         struct lsm_ioctlop_audit ioctl;
3565         u32 ssid = cred_sid(cred);
3566         int rc;
3567         u8 driver = cmd >> 8;
3568         u8 xperm = cmd & 0xff;
3569
3570         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3571         ad.u.op = &ioctl;
3572         ad.u.op->cmd = cmd;
3573         ad.u.op->path = file->f_path;
3574
3575         if (ssid != fsec->sid) {
3576                 rc = avc_has_perm(&selinux_state,
3577                                   ssid, fsec->sid,
3578                                 SECCLASS_FD,
3579                                 FD__USE,
3580                                 &ad);
3581                 if (rc)
3582                         goto out;
3583         }
3584
3585         if (unlikely(IS_PRIVATE(inode)))
3586                 return 0;
3587
3588         isec = inode_security(inode);
3589         rc = avc_has_extended_perms(&selinux_state,
3590                                     ssid, isec->sid, isec->sclass,
3591                                     requested, driver, xperm, &ad);
3592 out:
3593         return rc;
3594 }
3595
3596 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3597                               unsigned long arg)
3598 {
3599         const struct cred *cred = current_cred();
3600         int error = 0;
3601
3602         switch (cmd) {
3603         case FIONREAD:
3604         /* fall through */
3605         case FIBMAP:
3606         /* fall through */
3607         case FIGETBSZ:
3608         /* fall through */
3609         case FS_IOC_GETFLAGS:
3610         /* fall through */
3611         case FS_IOC_GETVERSION:
3612                 error = file_has_perm(cred, file, FILE__GETATTR);
3613                 break;
3614
3615         case FS_IOC_SETFLAGS:
3616         /* fall through */
3617         case FS_IOC_SETVERSION:
3618                 error = file_has_perm(cred, file, FILE__SETATTR);
3619                 break;
3620
3621         /* sys_ioctl() checks */
3622         case FIONBIO:
3623         /* fall through */
3624         case FIOASYNC:
3625                 error = file_has_perm(cred, file, 0);
3626                 break;
3627
3628         case KDSKBENT:
3629         case KDSKBSENT:
3630                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3631                                             CAP_OPT_NONE, true);
3632                 break;
3633
3634         /* default case assumes that the command will go
3635          * to the file's ioctl() function.
3636          */
3637         default:
3638                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3639         }
3640         return error;
3641 }
3642
3643 static int default_noexec __ro_after_init;
3644
3645 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3646 {
3647         const struct cred *cred = current_cred();
3648         u32 sid = cred_sid(cred);
3649         int rc = 0;
3650
3651         if (default_noexec &&
3652             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3653                                    (!shared && (prot & PROT_WRITE)))) {
3654                 /*
3655                  * We are making executable an anonymous mapping or a
3656                  * private file mapping that will also be writable.
3657                  * This has an additional check.
3658                  */
3659                 rc = avc_has_perm(&selinux_state,
3660                                   sid, sid, SECCLASS_PROCESS,
3661                                   PROCESS__EXECMEM, NULL);
3662                 if (rc)
3663                         goto error;
3664         }
3665
3666         if (file) {
3667                 /* read access is always possible with a mapping */
3668                 u32 av = FILE__READ;
3669
3670                 /* write access only matters if the mapping is shared */
3671                 if (shared && (prot & PROT_WRITE))
3672                         av |= FILE__WRITE;
3673
3674                 if (prot & PROT_EXEC)
3675                         av |= FILE__EXECUTE;
3676
3677                 return file_has_perm(cred, file, av);
3678         }
3679
3680 error:
3681         return rc;
3682 }
3683
3684 static int selinux_mmap_addr(unsigned long addr)
3685 {
3686         int rc = 0;
3687
3688         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3689                 u32 sid = current_sid();
3690                 rc = avc_has_perm(&selinux_state,
3691                                   sid, sid, SECCLASS_MEMPROTECT,
3692                                   MEMPROTECT__MMAP_ZERO, NULL);
3693         }
3694
3695         return rc;
3696 }
3697
3698 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3699                              unsigned long prot, unsigned long flags)
3700 {
3701         struct common_audit_data ad;
3702         int rc;
3703
3704         if (file) {
3705                 ad.type = LSM_AUDIT_DATA_FILE;
3706                 ad.u.file = file;
3707                 rc = inode_has_perm(current_cred(), file_inode(file),
3708                                     FILE__MAP, &ad);
3709                 if (rc)
3710                         return rc;
3711         }
3712
3713         if (selinux_state.checkreqprot)
3714                 prot = reqprot;
3715
3716         return file_map_prot_check(file, prot,
3717                                    (flags & MAP_TYPE) == MAP_SHARED);
3718 }
3719
3720 static int selinux_file_mprotect(struct vm_area_struct *vma,
3721                                  unsigned long reqprot,
3722                                  unsigned long prot)
3723 {
3724         const struct cred *cred = current_cred();
3725         u32 sid = cred_sid(cred);
3726
3727         if (selinux_state.checkreqprot)
3728                 prot = reqprot;
3729
3730         if (default_noexec &&
3731             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3732                 int rc = 0;
3733                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3734                     vma->vm_end <= vma->vm_mm->brk) {
3735                         rc = avc_has_perm(&selinux_state,
3736                                           sid, sid, SECCLASS_PROCESS,
3737                                           PROCESS__EXECHEAP, NULL);
3738                 } else if (!vma->vm_file &&
3739                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3740                              vma->vm_end >= vma->vm_mm->start_stack) ||
3741                             vma_is_stack_for_current(vma))) {
3742                         rc = avc_has_perm(&selinux_state,
3743                                           sid, sid, SECCLASS_PROCESS,
3744                                           PROCESS__EXECSTACK, NULL);
3745                 } else if (vma->vm_file && vma->anon_vma) {
3746                         /*
3747                          * We are making executable a file mapping that has
3748                          * had some COW done. Since pages might have been
3749                          * written, check ability to execute the possibly
3750                          * modified content.  This typically should only
3751                          * occur for text relocations.
3752                          */
3753                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3754                 }
3755                 if (rc)
3756                         return rc;
3757         }
3758
3759         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3760 }
3761
3762 static int selinux_file_lock(struct file *file, unsigned int cmd)
3763 {
3764         const struct cred *cred = current_cred();
3765
3766         return file_has_perm(cred, file, FILE__LOCK);
3767 }
3768
3769 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3770                               unsigned long arg)
3771 {
3772         const struct cred *cred = current_cred();
3773         int err = 0;
3774
3775         switch (cmd) {
3776         case F_SETFL:
3777                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3778                         err = file_has_perm(cred, file, FILE__WRITE);
3779                         break;
3780                 }
3781                 /* fall through */
3782         case F_SETOWN:
3783         case F_SETSIG:
3784         case F_GETFL:
3785         case F_GETOWN:
3786         case F_GETSIG:
3787         case F_GETOWNER_UIDS:
3788                 /* Just check FD__USE permission */
3789                 err = file_has_perm(cred, file, 0);
3790                 break;
3791         case F_GETLK:
3792         case F_SETLK:
3793         case F_SETLKW:
3794         case F_OFD_GETLK:
3795         case F_OFD_SETLK:
3796         case F_OFD_SETLKW:
3797 #if BITS_PER_LONG == 32
3798         case F_GETLK64:
3799         case F_SETLK64:
3800         case F_SETLKW64:
3801 #endif
3802                 err = file_has_perm(cred, file, FILE__LOCK);
3803                 break;
3804         }
3805
3806         return err;
3807 }
3808
3809 static void selinux_file_set_fowner(struct file *file)
3810 {
3811         struct file_security_struct *fsec;
3812
3813         fsec = selinux_file(file);
3814         fsec->fown_sid = current_sid();
3815 }
3816
3817 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3818                                        struct fown_struct *fown, int signum)
3819 {
3820         struct file *file;
3821         u32 sid = task_sid(tsk);
3822         u32 perm;
3823         struct file_security_struct *fsec;
3824
3825         /* struct fown_struct is never outside the context of a struct file */
3826         file = container_of(fown, struct file, f_owner);
3827
3828         fsec = selinux_file(file);
3829
3830         if (!signum)
3831                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3832         else
3833                 perm = signal_to_av(signum);
3834
3835         return avc_has_perm(&selinux_state,
3836                             fsec->fown_sid, sid,
3837                             SECCLASS_PROCESS, perm, NULL);
3838 }
3839
3840 static int selinux_file_receive(struct file *file)
3841 {
3842         const struct cred *cred = current_cred();
3843
3844         return file_has_perm(cred, file, file_to_av(file));
3845 }
3846
3847 static int selinux_file_open(struct file *file)
3848 {
3849         struct file_security_struct *fsec;
3850         struct inode_security_struct *isec;
3851
3852         fsec = selinux_file(file);
3853         isec = inode_security(file_inode(file));
3854         /*
3855          * Save inode label and policy sequence number
3856          * at open-time so that selinux_file_permission
3857          * can determine whether revalidation is necessary.
3858          * Task label is already saved in the file security
3859          * struct as its SID.
3860          */
3861         fsec->isid = isec->sid;
3862         fsec->pseqno = avc_policy_seqno(&selinux_state);
3863         /*
3864          * Since the inode label or policy seqno may have changed
3865          * between the selinux_inode_permission check and the saving
3866          * of state above, recheck that access is still permitted.
3867          * Otherwise, access might never be revalidated against the
3868          * new inode label or new policy.
3869          * This check is not redundant - do not remove.
3870          */
3871         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3872 }
3873
3874 /* task security operations */
3875
3876 static int selinux_task_alloc(struct task_struct *task,
3877                               unsigned long clone_flags)
3878 {
3879         u32 sid = current_sid();
3880
3881         return avc_has_perm(&selinux_state,
3882                             sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3883 }
3884
3885 /*
3886  * prepare a new set of credentials for modification
3887  */
3888 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3889                                 gfp_t gfp)
3890 {
3891         const struct task_security_struct *old_tsec = selinux_cred(old);
3892         struct task_security_struct *tsec = selinux_cred(new);
3893
3894         *tsec = *old_tsec;
3895         return 0;
3896 }
3897
3898 /*
3899  * transfer the SELinux data to a blank set of creds
3900  */
3901 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3902 {
3903         const struct task_security_struct *old_tsec = selinux_cred(old);
3904         struct task_security_struct *tsec = selinux_cred(new);
3905
3906         *tsec = *old_tsec;
3907 }
3908
3909 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3910 {
3911         *secid = cred_sid(c);
3912 }
3913
3914 /*
3915  * set the security data for a kernel service
3916  * - all the creation contexts are set to unlabelled
3917  */
3918 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3919 {
3920         struct task_security_struct *tsec = selinux_cred(new);
3921         u32 sid = current_sid();
3922         int ret;
3923
3924         ret = avc_has_perm(&selinux_state,
3925                            sid, secid,
3926                            SECCLASS_KERNEL_SERVICE,
3927                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3928                            NULL);
3929         if (ret == 0) {
3930                 tsec->sid = secid;
3931                 tsec->create_sid = 0;
3932                 tsec->keycreate_sid = 0;
3933                 tsec->sockcreate_sid = 0;
3934         }
3935         return ret;
3936 }
3937
3938 /*
3939  * set the file creation context in a security record to the same as the
3940  * objective context of the specified inode
3941  */
3942 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3943 {
3944         struct inode_security_struct *isec = inode_security(inode);
3945         struct task_security_struct *tsec = selinux_cred(new);
3946         u32 sid = current_sid();
3947         int ret;
3948
3949         ret = avc_has_perm(&selinux_state,
3950                            sid, isec->sid,
3951                            SECCLASS_KERNEL_SERVICE,
3952                            KERNEL_SERVICE__CREATE_FILES_AS,
3953                            NULL);
3954
3955         if (ret == 0)
3956                 tsec->create_sid = isec->sid;
3957         return ret;
3958 }
3959
3960 static int selinux_kernel_module_request(char *kmod_name)
3961 {
3962         struct common_audit_data ad;
3963
3964         ad.type = LSM_AUDIT_DATA_KMOD;
3965         ad.u.kmod_name = kmod_name;
3966
3967         return avc_has_perm(&selinux_state,
3968                             current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3969                             SYSTEM__MODULE_REQUEST, &ad);
3970 }
3971
3972 static int selinux_kernel_module_from_file(struct file *file)
3973 {
3974         struct common_audit_data ad;
3975         struct inode_security_struct *isec;
3976         struct file_security_struct *fsec;
3977         u32 sid = current_sid();
3978         int rc;
3979
3980         /* init_module */
3981         if (file == NULL)
3982                 return avc_has_perm(&selinux_state,
3983                                     sid, sid, SECCLASS_SYSTEM,
3984                                         SYSTEM__MODULE_LOAD, NULL);
3985
3986         /* finit_module */
3987
3988         ad.type = LSM_AUDIT_DATA_FILE;
3989         ad.u.file = file;
3990
3991         fsec = selinux_file(file);
3992         if (sid != fsec->sid) {
3993                 rc = avc_has_perm(&selinux_state,
3994                                   sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3995                 if (rc)
3996                         return rc;
3997         }
3998
3999         isec = inode_security(file_inode(file));
4000         return avc_has_perm(&selinux_state,
4001                             sid, isec->sid, SECCLASS_SYSTEM,
4002                                 SYSTEM__MODULE_LOAD, &ad);
4003 }
4004
4005 static int selinux_kernel_read_file(struct file *file,
4006                                     enum kernel_read_file_id id)
4007 {
4008         int rc = 0;
4009
4010         switch (id) {
4011         case READING_MODULE:
4012                 rc = selinux_kernel_module_from_file(file);
4013                 break;
4014         default:
4015                 break;
4016         }
4017
4018         return rc;
4019 }
4020
4021 static int selinux_kernel_load_data(enum kernel_load_data_id id)
4022 {
4023         int rc = 0;
4024
4025         switch (id) {
4026         case LOADING_MODULE:
4027                 rc = selinux_kernel_module_from_file(NULL);
4028         default:
4029                 break;
4030         }
4031
4032         return rc;
4033 }
4034
4035 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4036 {
4037         return avc_has_perm(&selinux_state,
4038                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4039                             PROCESS__SETPGID, NULL);
4040 }
4041
4042 static int selinux_task_getpgid(struct task_struct *p)
4043 {
4044         return avc_has_perm(&selinux_state,
4045                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4046                             PROCESS__GETPGID, NULL);
4047 }
4048
4049 static int selinux_task_getsid(struct task_struct *p)
4050 {
4051         return avc_has_perm(&selinux_state,
4052                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4053                             PROCESS__GETSESSION, NULL);
4054 }
4055
4056 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4057 {
4058         *secid = task_sid(p);
4059 }
4060
4061 static int selinux_task_setnice(struct task_struct *p, int nice)
4062 {
4063         return avc_has_perm(&selinux_state,
4064                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4065                             PROCESS__SETSCHED, NULL);
4066 }
4067
4068 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4069 {
4070         return avc_has_perm(&selinux_state,
4071                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4072                             PROCESS__SETSCHED, NULL);
4073 }
4074
4075 static int selinux_task_getioprio(struct task_struct *p)
4076 {
4077         return avc_has_perm(&selinux_state,
4078                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4079                             PROCESS__GETSCHED, NULL);
4080 }
4081
4082 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4083                                 unsigned int flags)
4084 {
4085         u32 av = 0;
4086
4087         if (!flags)
4088                 return 0;
4089         if (flags & LSM_PRLIMIT_WRITE)
4090                 av |= PROCESS__SETRLIMIT;
4091         if (flags & LSM_PRLIMIT_READ)
4092                 av |= PROCESS__GETRLIMIT;
4093         return avc_has_perm(&selinux_state,
4094                             cred_sid(cred), cred_sid(tcred),
4095                             SECCLASS_PROCESS, av, NULL);
4096 }
4097
4098 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4099                 struct rlimit *new_rlim)
4100 {
4101         struct rlimit *old_rlim = p->signal->rlim + resource;
4102
4103         /* Control the ability to change the hard limit (whether
4104            lowering or raising it), so that the hard limit can
4105            later be used as a safe reset point for the soft limit
4106            upon context transitions.  See selinux_bprm_committing_creds. */
4107         if (old_rlim->rlim_max != new_rlim->rlim_max)
4108                 return avc_has_perm(&selinux_state,
4109                                     current_sid(), task_sid(p),
4110                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4111
4112         return 0;
4113 }
4114
4115 static int selinux_task_setscheduler(struct task_struct *p)
4116 {
4117         return avc_has_perm(&selinux_state,
4118                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4119                             PROCESS__SETSCHED, NULL);
4120 }
4121
4122 static int selinux_task_getscheduler(struct task_struct *p)
4123 {
4124         return avc_has_perm(&selinux_state,
4125                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4126                             PROCESS__GETSCHED, NULL);
4127 }
4128
4129 static int selinux_task_movememory(struct task_struct *p)
4130 {
4131         return avc_has_perm(&selinux_state,
4132                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4133                             PROCESS__SETSCHED, NULL);
4134 }
4135
4136 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4137                                 int sig, const struct cred *cred)
4138 {
4139         u32 secid;
4140         u32 perm;
4141
4142         if (!sig)
4143                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4144         else
4145                 perm = signal_to_av(sig);
4146         if (!cred)
4147                 secid = current_sid();
4148         else
4149                 secid = cred_sid(cred);
4150         return avc_has_perm(&selinux_state,
4151                             secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4152 }
4153
4154 static void selinux_task_to_inode(struct task_struct *p,
4155                                   struct inode *inode)
4156 {
4157         struct inode_security_struct *isec = selinux_inode(inode);
4158         u32 sid = task_sid(p);
4159
4160         spin_lock(&isec->lock);
4161         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4162         isec->sid = sid;
4163         isec->initialized = LABEL_INITIALIZED;
4164         spin_unlock(&isec->lock);
4165 }
4166
4167 /* Returns error only if unable to parse addresses */
4168 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4169                         struct common_audit_data *ad, u8 *proto)
4170 {
4171         int offset, ihlen, ret = -EINVAL;
4172         struct iphdr _iph, *ih;
4173
4174         offset = skb_network_offset(skb);
4175         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4176         if (ih == NULL)
4177                 goto out;
4178
4179         ihlen = ih->ihl * 4;
4180         if (ihlen < sizeof(_iph))
4181                 goto out;
4182
4183         ad->u.net->v4info.saddr = ih->saddr;
4184         ad->u.net->v4info.daddr = ih->daddr;
4185         ret = 0;
4186
4187         if (proto)
4188                 *proto = ih->protocol;
4189
4190         switch (ih->protocol) {
4191         case IPPROTO_TCP: {
4192                 struct tcphdr _tcph, *th;
4193
4194                 if (ntohs(ih->frag_off) & IP_OFFSET)
4195                         break;
4196
4197                 offset += ihlen;
4198                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4199                 if (th == NULL)
4200                         break;
4201
4202                 ad->u.net->sport = th->source;
4203                 ad->u.net->dport = th->dest;
4204                 break;
4205         }
4206
4207         case IPPROTO_UDP: {
4208                 struct udphdr _udph, *uh;
4209
4210                 if (ntohs(ih->frag_off) & IP_OFFSET)
4211                         break;
4212
4213                 offset += ihlen;
4214                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4215                 if (uh == NULL)
4216                         break;
4217
4218                 ad->u.net->sport = uh->source;
4219                 ad->u.net->dport = uh->dest;
4220                 break;
4221         }
4222
4223         case IPPROTO_DCCP: {
4224                 struct dccp_hdr _dccph, *dh;
4225
4226                 if (ntohs(ih->frag_off) & IP_OFFSET)
4227                         break;
4228
4229                 offset += ihlen;
4230                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4231                 if (dh == NULL)
4232                         break;
4233
4234                 ad->u.net->sport = dh->dccph_sport;
4235                 ad->u.net->dport = dh->dccph_dport;
4236                 break;
4237         }
4238
4239 #if IS_ENABLED(CONFIG_IP_SCTP)
4240         case IPPROTO_SCTP: {
4241                 struct sctphdr _sctph, *sh;
4242
4243                 if (ntohs(ih->frag_off) & IP_OFFSET)
4244                         break;
4245
4246                 offset += ihlen;
4247                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4248                 if (sh == NULL)
4249                         break;
4250
4251                 ad->u.net->sport = sh->source;
4252                 ad->u.net->dport = sh->dest;
4253                 break;
4254         }
4255 #endif
4256         default:
4257                 break;
4258         }
4259 out:
4260         return ret;
4261 }
4262
4263 #if IS_ENABLED(CONFIG_IPV6)
4264
4265 /* Returns error only if unable to parse addresses */
4266 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4267                         struct common_audit_data *ad, u8 *proto)
4268 {
4269         u8 nexthdr;
4270         int ret = -EINVAL, offset;
4271         struct ipv6hdr _ipv6h, *ip6;
4272         __be16 frag_off;
4273
4274         offset = skb_network_offset(skb);
4275         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4276         if (ip6 == NULL)
4277                 goto out;
4278
4279         ad->u.net->v6info.saddr = ip6->saddr;
4280         ad->u.net->v6info.daddr = ip6->daddr;
4281         ret = 0;
4282
4283         nexthdr = ip6->nexthdr;
4284         offset += sizeof(_ipv6h);
4285         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4286         if (offset < 0)
4287                 goto out;
4288
4289         if (proto)
4290                 *proto = nexthdr;
4291
4292         switch (nexthdr) {
4293         case IPPROTO_TCP: {
4294                 struct tcphdr _tcph, *th;
4295
4296                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4297                 if (th == NULL)
4298                         break;
4299
4300                 ad->u.net->sport = th->source;
4301                 ad->u.net->dport = th->dest;
4302                 break;
4303         }
4304
4305         case IPPROTO_UDP: {
4306                 struct udphdr _udph, *uh;
4307
4308                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4309                 if (uh == NULL)
4310                         break;
4311
4312                 ad->u.net->sport = uh->source;
4313                 ad->u.net->dport = uh->dest;
4314                 break;
4315         }
4316
4317         case IPPROTO_DCCP: {
4318                 struct dccp_hdr _dccph, *dh;
4319
4320                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4321                 if (dh == NULL)
4322                         break;
4323
4324                 ad->u.net->sport = dh->dccph_sport;
4325                 ad->u.net->dport = dh->dccph_dport;
4326                 break;
4327         }
4328
4329 #if IS_ENABLED(CONFIG_IP_SCTP)
4330         case IPPROTO_SCTP: {
4331                 struct sctphdr _sctph, *sh;
4332
4333                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4334                 if (sh == NULL)
4335                         break;
4336
4337                 ad->u.net->sport = sh->source;
4338                 ad->u.net->dport = sh->dest;
4339                 break;
4340         }
4341 #endif
4342         /* includes fragments */
4343         default:
4344                 break;
4345         }
4346 out:
4347         return ret;
4348 }
4349
4350 #endif /* IPV6 */
4351
4352 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4353                              char **_addrp, int src, u8 *proto)
4354 {
4355         char *addrp;
4356         int ret;
4357
4358         switch (ad->u.net->family) {
4359         case PF_INET:
4360                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4361                 if (ret)
4362                         goto parse_error;
4363                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4364                                        &ad->u.net->v4info.daddr);
4365                 goto okay;
4366
4367 #if IS_ENABLED(CONFIG_IPV6)
4368         case PF_INET6:
4369                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4370                 if (ret)
4371                         goto parse_error;
4372                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4373                                        &ad->u.net->v6info.daddr);
4374                 goto okay;
4375 #endif  /* IPV6 */
4376         default:
4377                 addrp = NULL;
4378                 goto okay;
4379         }
4380
4381 parse_error:
4382         pr_warn(
4383                "SELinux: failure in selinux_parse_skb(),"
4384                " unable to parse packet\n");
4385         return ret;
4386
4387 okay:
4388         if (_addrp)
4389                 *_addrp = addrp;
4390         return 0;
4391 }
4392
4393 /**
4394  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4395  * @skb: the packet
4396  * @family: protocol family
4397  * @sid: the packet's peer label SID
4398  *
4399  * Description:
4400  * Check the various different forms of network peer labeling and determine
4401  * the peer label/SID for the packet; most of the magic actually occurs in
4402  * the security server function security_net_peersid_cmp().  The function
4403  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4404  * or -EACCES if @sid is invalid due to inconsistencies with the different
4405  * peer labels.
4406  *
4407  */
4408 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4409 {
4410         int err;
4411         u32 xfrm_sid;
4412         u32 nlbl_sid;
4413         u32 nlbl_type;
4414
4415         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4416         if (unlikely(err))
4417                 return -EACCES;
4418         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4419         if (unlikely(err))
4420                 return -EACCES;
4421
4422         err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4423                                            nlbl_type, xfrm_sid, sid);
4424         if (unlikely(err)) {
4425                 pr_warn(
4426                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4427                        " unable to determine packet's peer label\n");
4428                 return -EACCES;
4429         }
4430
4431         return 0;
4432 }
4433
4434 /**
4435  * selinux_conn_sid - Determine the child socket label for a connection
4436  * @sk_sid: the parent socket's SID
4437  * @skb_sid: the packet's SID
4438  * @conn_sid: the resulting connection SID
4439  *
4440  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4441  * combined with the MLS information from @skb_sid in order to create
4442  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4443  * of @sk_sid.  Returns zero on success, negative values on failure.
4444  *
4445  */
4446 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4447 {
4448         int err = 0;
4449
4450         if (skb_sid != SECSID_NULL)
4451                 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4452                                             conn_sid);
4453         else
4454                 *conn_sid = sk_sid;
4455
4456         return err;
4457 }
4458
4459 /* socket security operations */
4460
4461 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4462                                  u16 secclass, u32 *socksid)
4463 {
4464         if (tsec->sockcreate_sid > SECSID_NULL) {
4465                 *socksid = tsec->sockcreate_sid;
4466                 return 0;
4467         }
4468
4469         return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4470                                        secclass, NULL, socksid);
4471 }
4472
4473 static int sock_has_perm(struct sock *sk, u32 perms)
4474 {
4475         struct sk_security_struct *sksec = sk->sk_security;
4476         struct common_audit_data ad;
4477         struct lsm_network_audit net = {0,};
4478
4479         if (sksec->sid == SECINITSID_KERNEL)
4480                 return 0;
4481
4482         ad.type = LSM_AUDIT_DATA_NET;
4483         ad.u.net = &net;
4484         ad.u.net->sk = sk;
4485
4486         return avc_has_perm(&selinux_state,
4487                             current_sid(), sksec->sid, sksec->sclass, perms,
4488                             &ad);
4489 }
4490
4491 static int selinux_socket_create(int family, int type,
4492                                  int protocol, int kern)
4493 {
4494         const struct task_security_struct *tsec = selinux_cred(current_cred());
4495         u32 newsid;
4496         u16 secclass;
4497         int rc;
4498
4499         if (kern)
4500                 return 0;
4501
4502         secclass = socket_type_to_security_class(family, type, protocol);
4503         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4504         if (rc)
4505                 return rc;
4506
4507         return avc_has_perm(&selinux_state,
4508                             tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4509 }
4510
4511 static int selinux_socket_post_create(struct socket *sock, int family,
4512                                       int type, int protocol, int kern)
4513 {
4514         const struct task_security_struct *tsec = selinux_cred(current_cred());
4515         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4516         struct sk_security_struct *sksec;
4517         u16 sclass = socket_type_to_security_class(family, type, protocol);
4518         u32 sid = SECINITSID_KERNEL;
4519         int err = 0;
4520
4521         if (!kern) {
4522                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4523                 if (err)
4524                         return err;
4525         }
4526
4527         isec->sclass = sclass;
4528         isec->sid = sid;
4529         isec->initialized = LABEL_INITIALIZED;
4530
4531         if (sock->sk) {
4532                 sksec = sock->sk->sk_security;
4533                 sksec->sclass = sclass;
4534                 sksec->sid = sid;
4535                 /* Allows detection of the first association on this socket */
4536                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4537                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4538
4539                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4540         }
4541
4542         return err;
4543 }
4544
4545 static int selinux_socket_socketpair(struct socket *socka,
4546                                      struct socket *sockb)
4547 {
4548         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4549         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4550
4551         sksec_a->peer_sid = sksec_b->sid;
4552         sksec_b->peer_sid = sksec_a->sid;
4553
4554         return 0;
4555 }
4556
4557 /* Range of port numbers used to automatically bind.
4558    Need to determine whether we should perform a name_bind
4559    permission check between the socket and the port number. */
4560
4561 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4562 {
4563         struct sock *sk = sock->sk;
4564         struct sk_security_struct *sksec = sk->sk_security;
4565         u16 family;
4566         int err;
4567
4568         err = sock_has_perm(sk, SOCKET__BIND);
4569         if (err)
4570                 goto out;
4571
4572         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4573         family = sk->sk_family;
4574         if (family == PF_INET || family == PF_INET6) {
4575                 char *addrp;
4576                 struct common_audit_data ad;
4577                 struct lsm_network_audit net = {0,};
4578                 struct sockaddr_in *addr4 = NULL;
4579                 struct sockaddr_in6 *addr6 = NULL;
4580                 u16 family_sa;
4581                 unsigned short snum;
4582                 u32 sid, node_perm;
4583
4584                 /*
4585                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4586                  * that validates multiple binding addresses. Because of this
4587                  * need to check address->sa_family as it is possible to have
4588                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4589                  */
4590                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4591                         return -EINVAL;
4592                 family_sa = address->sa_family;
4593                 switch (family_sa) {
4594                 case AF_UNSPEC:
4595                 case AF_INET:
4596                         if (addrlen < sizeof(struct sockaddr_in))
4597                                 return -EINVAL;
4598                         addr4 = (struct sockaddr_in *)address;
4599                         if (family_sa == AF_UNSPEC) {
4600                                 /* see __inet_bind(), we only want to allow
4601                                  * AF_UNSPEC if the address is INADDR_ANY
4602                                  */
4603                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4604                                         goto err_af;
4605                                 family_sa = AF_INET;
4606                         }
4607                         snum = ntohs(addr4->sin_port);
4608                         addrp = (char *)&addr4->sin_addr.s_addr;
4609                         break;
4610                 case AF_INET6:
4611                         if (addrlen < SIN6_LEN_RFC2133)
4612                                 return -EINVAL;
4613                         addr6 = (struct sockaddr_in6 *)address;
4614                         snum = ntohs(addr6->sin6_port);
4615                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4616                         break;
4617                 default:
4618                         goto err_af;
4619                 }
4620
4621                 ad.type = LSM_AUDIT_DATA_NET;
4622                 ad.u.net = &net;
4623                 ad.u.net->sport = htons(snum);
4624                 ad.u.net->family = family_sa;
4625
4626                 if (snum) {
4627                         int low, high;
4628
4629                         inet_get_local_port_range(sock_net(sk), &low, &high);
4630
4631                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4632                             snum < low || snum > high) {
4633                                 err = sel_netport_sid(sk->sk_protocol,
4634                                                       snum, &sid);
4635                                 if (err)
4636                                         goto out;
4637                                 err = avc_has_perm(&selinux_state,
4638                                                    sksec->sid, sid,
4639                                                    sksec->sclass,
4640                                                    SOCKET__NAME_BIND, &ad);
4641                                 if (err)
4642                                         goto out;
4643                         }
4644                 }
4645
4646                 switch (sksec->sclass) {
4647                 case SECCLASS_TCP_SOCKET:
4648                         node_perm = TCP_SOCKET__NODE_BIND;
4649                         break;
4650
4651                 case SECCLASS_UDP_SOCKET:
4652                         node_perm = UDP_SOCKET__NODE_BIND;
4653                         break;
4654
4655                 case SECCLASS_DCCP_SOCKET:
4656                         node_perm = DCCP_SOCKET__NODE_BIND;
4657                         break;
4658
4659                 case SECCLASS_SCTP_SOCKET:
4660                         node_perm = SCTP_SOCKET__NODE_BIND;
4661                         break;
4662
4663                 default:
4664                         node_perm = RAWIP_SOCKET__NODE_BIND;
4665                         break;
4666                 }
4667
4668                 err = sel_netnode_sid(addrp, family_sa, &sid);
4669                 if (err)
4670                         goto out;
4671
4672                 if (family_sa == AF_INET)
4673                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4674                 else
4675                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4676
4677                 err = avc_has_perm(&selinux_state,
4678                                    sksec->sid, sid,
4679                                    sksec->sclass, node_perm, &ad);
4680                 if (err)
4681                         goto out;
4682         }
4683 out:
4684         return err;
4685 err_af:
4686         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4687         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4688                 return -EINVAL;
4689         return -EAFNOSUPPORT;
4690 }
4691
4692 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4693  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4694  */
4695 static int selinux_socket_connect_helper(struct socket *sock,
4696                                          struct sockaddr *address, int addrlen)
4697 {
4698         struct sock *sk = sock->sk;
4699         struct sk_security_struct *sksec = sk->sk_security;
4700         int err;
4701
4702         err = sock_has_perm(sk, SOCKET__CONNECT);
4703         if (err)
4704                 return err;
4705         if (addrlen < offsetofend(struct sockaddr, sa_family))
4706                 return -EINVAL;
4707
4708         /* connect(AF_UNSPEC) has special handling, as it is a documented
4709          * way to disconnect the socket
4710          */
4711         if (address->sa_family == AF_UNSPEC)
4712                 return 0;
4713
4714         /*
4715          * If a TCP, DCCP or SCTP socket, check name_connect permission
4716          * for the port.
4717          */
4718         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4719             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4720             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4721                 struct common_audit_data ad;
4722                 struct lsm_network_audit net = {0,};
4723                 struct sockaddr_in *addr4 = NULL;
4724                 struct sockaddr_in6 *addr6 = NULL;
4725                 unsigned short snum;
4726                 u32 sid, perm;
4727
4728                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4729                  * that validates multiple connect addresses. Because of this
4730                  * need to check address->sa_family as it is possible to have
4731                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4732                  */
4733                 switch (address->sa_family) {
4734                 case AF_INET:
4735                         addr4 = (struct sockaddr_in *)address;
4736                         if (addrlen < sizeof(struct sockaddr_in))
4737                                 return -EINVAL;
4738                         snum = ntohs(addr4->sin_port);
4739                         break;
4740                 case AF_INET6:
4741                         addr6 = (struct sockaddr_in6 *)address;
4742                         if (addrlen < SIN6_LEN_RFC2133)
4743                                 return -EINVAL;
4744                         snum = ntohs(addr6->sin6_port);
4745                         break;
4746                 default:
4747                         /* Note that SCTP services expect -EINVAL, whereas
4748                          * others expect -EAFNOSUPPORT.
4749                          */
4750                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4751                                 return -EINVAL;
4752                         else
4753                                 return -EAFNOSUPPORT;
4754                 }
4755
4756                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4757                 if (err)
4758                         return err;
4759
4760                 switch (sksec->sclass) {
4761                 case SECCLASS_TCP_SOCKET:
4762                         perm = TCP_SOCKET__NAME_CONNECT;
4763                         break;
4764                 case SECCLASS_DCCP_SOCKET:
4765                         perm = DCCP_SOCKET__NAME_CONNECT;
4766                         break;
4767                 case SECCLASS_SCTP_SOCKET:
4768                         perm = SCTP_SOCKET__NAME_CONNECT;
4769                         break;
4770                 }
4771
4772                 ad.type = LSM_AUDIT_DATA_NET;
4773                 ad.u.net = &net;
4774                 ad.u.net->dport = htons(snum);
4775                 ad.u.net->family = address->sa_family;
4776                 err = avc_has_perm(&selinux_state,
4777                                    sksec->sid, sid, sksec->sclass, perm, &ad);
4778                 if (err)
4779                         return err;
4780         }
4781
4782         return 0;
4783 }
4784
4785 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4786 static int selinux_socket_connect(struct socket *sock,
4787                                   struct sockaddr *address, int addrlen)
4788 {
4789         int err;
4790         struct sock *sk = sock->sk;
4791
4792         err = selinux_socket_connect_helper(sock, address, addrlen);
4793         if (err)
4794                 return err;
4795
4796         return selinux_netlbl_socket_connect(sk, address);
4797 }
4798
4799 static int selinux_socket_listen(struct socket *sock, int backlog)
4800 {
4801         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4802 }
4803
4804 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4805 {
4806         int err;
4807         struct inode_security_struct *isec;
4808         struct inode_security_struct *newisec;
4809         u16 sclass;
4810         u32 sid;
4811
4812         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4813         if (err)
4814                 return err;
4815
4816         isec = inode_security_novalidate(SOCK_INODE(sock));
4817         spin_lock(&isec->lock);
4818         sclass = isec->sclass;
4819         sid = isec->sid;
4820         spin_unlock(&isec->lock);
4821
4822         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4823         newisec->sclass = sclass;
4824         newisec->sid = sid;
4825         newisec->initialized = LABEL_INITIALIZED;
4826
4827         return 0;
4828 }
4829
4830 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4831                                   int size)
4832 {
4833         return sock_has_perm(sock->sk, SOCKET__WRITE);
4834 }
4835
4836 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4837                                   int size, int flags)
4838 {
4839         return sock_has_perm(sock->sk, SOCKET__READ);
4840 }
4841
4842 static int selinux_socket_getsockname(struct socket *sock)
4843 {
4844         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4845 }
4846
4847 static int selinux_socket_getpeername(struct socket *sock)
4848 {
4849         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4850 }
4851
4852 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4853 {
4854         int err;
4855
4856         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4857         if (err)
4858                 return err;
4859
4860         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4861 }
4862
4863 static int selinux_socket_getsockopt(struct socket *sock, int level,
4864                                      int optname)
4865 {
4866         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4867 }
4868
4869 static int selinux_socket_shutdown(struct socket *sock, int how)
4870 {
4871         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4872 }
4873
4874 static int selinux_socket_unix_stream_connect(struct sock *sock,
4875                                               struct sock *other,
4876                                               struct sock *newsk)
4877 {
4878         struct sk_security_struct *sksec_sock = sock->sk_security;
4879         struct sk_security_struct *sksec_other = other->sk_security;
4880         struct sk_security_struct *sksec_new = newsk->sk_security;
4881         struct common_audit_data ad;
4882         struct lsm_network_audit net = {0,};
4883         int err;
4884
4885         ad.type = LSM_AUDIT_DATA_NET;
4886         ad.u.net = &net;
4887         ad.u.net->sk = other;
4888
4889         err = avc_has_perm(&selinux_state,
4890                            sksec_sock->sid, sksec_other->sid,
4891                            sksec_other->sclass,
4892                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4893         if (err)
4894                 return err;
4895
4896         /* server child socket */
4897         sksec_new->peer_sid = sksec_sock->sid;
4898         err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4899                                     sksec_sock->sid, &sksec_new->sid);
4900         if (err)
4901                 return err;
4902
4903         /* connecting socket */
4904         sksec_sock->peer_sid = sksec_new->sid;
4905
4906         return 0;
4907 }
4908
4909 static int selinux_socket_unix_may_send(struct socket *sock,
4910                                         struct socket *other)
4911 {
4912         struct sk_security_struct *ssec = sock->sk->sk_security;
4913         struct sk_security_struct *osec = other->sk->sk_security;
4914         struct common_audit_data ad;
4915         struct lsm_network_audit net = {0,};
4916
4917         ad.type = LSM_AUDIT_DATA_NET;
4918         ad.u.net = &net;
4919         ad.u.net->sk = other->sk;
4920
4921         return avc_has_perm(&selinux_state,
4922                             ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4923                             &ad);
4924 }
4925
4926 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4927                                     char *addrp, u16 family, u32 peer_sid,
4928                                     struct common_audit_data *ad)
4929 {
4930         int err;
4931         u32 if_sid;
4932         u32 node_sid;
4933
4934         err = sel_netif_sid(ns, ifindex, &if_sid);
4935         if (err)
4936                 return err;
4937         err = avc_has_perm(&selinux_state,
4938                            peer_sid, if_sid,
4939                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4940         if (err)
4941                 return err;
4942
4943         err = sel_netnode_sid(addrp, family, &node_sid);
4944         if (err)
4945                 return err;
4946         return avc_has_perm(&selinux_state,
4947                             peer_sid, node_sid,
4948                             SECCLASS_NODE, NODE__RECVFROM, ad);
4949 }
4950
4951 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4952                                        u16 family)
4953 {
4954         int err = 0;
4955         struct sk_security_struct *sksec = sk->sk_security;
4956         u32 sk_sid = sksec->sid;
4957         struct common_audit_data ad;
4958         struct lsm_network_audit net = {0,};
4959         char *addrp;
4960
4961         ad.type = LSM_AUDIT_DATA_NET;
4962         ad.u.net = &net;
4963         ad.u.net->netif = skb->skb_iif;
4964         ad.u.net->family = family;
4965         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4966         if (err)
4967                 return err;
4968
4969         if (selinux_secmark_enabled()) {
4970                 err = avc_has_perm(&selinux_state,
4971                                    sk_sid, skb->secmark, SECCLASS_PACKET,
4972                                    PACKET__RECV, &ad);
4973                 if (err)
4974                         return err;
4975         }
4976
4977         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4978         if (err)
4979                 return err;
4980         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4981
4982         return err;
4983 }
4984
4985 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4986 {
4987         int err;
4988         struct sk_security_struct *sksec = sk->sk_security;
4989         u16 family = sk->sk_family;
4990         u32 sk_sid = sksec->sid;
4991         struct common_audit_data ad;
4992         struct lsm_network_audit net = {0,};
4993         char *addrp;
4994         u8 secmark_active;
4995         u8 peerlbl_active;
4996
4997         if (family != PF_INET && family != PF_INET6)
4998                 return 0;
4999
5000         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5001         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5002                 family = PF_INET;
5003
5004         /* If any sort of compatibility mode is enabled then handoff processing
5005          * to the selinux_sock_rcv_skb_compat() function to deal with the
5006          * special handling.  We do this in an attempt to keep this function
5007          * as fast and as clean as possible. */
5008         if (!selinux_policycap_netpeer())
5009                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5010
5011         secmark_active = selinux_secmark_enabled();
5012         peerlbl_active = selinux_peerlbl_enabled();
5013         if (!secmark_active && !peerlbl_active)
5014                 return 0;
5015
5016         ad.type = LSM_AUDIT_DATA_NET;
5017         ad.u.net = &net;
5018         ad.u.net->netif = skb->skb_iif;
5019         ad.u.net->family = family;
5020         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5021         if (err)
5022                 return err;
5023
5024         if (peerlbl_active) {
5025                 u32 peer_sid;
5026
5027                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5028                 if (err)
5029                         return err;
5030                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5031                                                addrp, family, peer_sid, &ad);
5032                 if (err) {
5033                         selinux_netlbl_err(skb, family, err, 0);
5034                         return err;
5035                 }
5036                 err = avc_has_perm(&selinux_state,
5037                                    sk_sid, peer_sid, SECCLASS_PEER,
5038                                    PEER__RECV, &ad);
5039                 if (err) {
5040                         selinux_netlbl_err(skb, family, err, 0);
5041                         return err;
5042                 }
5043         }
5044
5045         if (secmark_active) {
5046                 err = avc_has_perm(&selinux_state,
5047                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5048                                    PACKET__RECV, &ad);
5049                 if (err)
5050                         return err;
5051         }
5052
5053         return err;
5054 }
5055
5056 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5057                                             int __user *optlen, unsigned len)
5058 {
5059         int err = 0;
5060         char *scontext;
5061         u32 scontext_len;
5062         struct sk_security_struct *sksec = sock->sk->sk_security;
5063         u32 peer_sid = SECSID_NULL;
5064
5065         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5066             sksec->sclass == SECCLASS_TCP_SOCKET ||
5067             sksec->sclass == SECCLASS_SCTP_SOCKET)
5068                 peer_sid = sksec->peer_sid;
5069         if (peer_sid == SECSID_NULL)
5070                 return -ENOPROTOOPT;
5071
5072         err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5073                                       &scontext_len);
5074         if (err)
5075                 return err;
5076
5077         if (scontext_len > len) {
5078                 err = -ERANGE;
5079                 goto out_len;
5080         }
5081
5082         if (copy_to_user(optval, scontext, scontext_len))
5083                 err = -EFAULT;
5084
5085 out_len:
5086         if (put_user(scontext_len, optlen))
5087                 err = -EFAULT;
5088         kfree(scontext);
5089         return err;
5090 }
5091
5092 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5093 {
5094         u32 peer_secid = SECSID_NULL;
5095         u16 family;
5096         struct inode_security_struct *isec;
5097
5098         if (skb && skb->protocol == htons(ETH_P_IP))
5099                 family = PF_INET;
5100         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5101                 family = PF_INET6;
5102         else if (sock)
5103                 family = sock->sk->sk_family;
5104         else
5105                 goto out;
5106
5107         if (sock && family == PF_UNIX) {
5108                 isec = inode_security_novalidate(SOCK_INODE(sock));
5109                 peer_secid = isec->sid;
5110         } else if (skb)
5111                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5112
5113 out:
5114         *secid = peer_secid;
5115         if (peer_secid == SECSID_NULL)
5116                 return -EINVAL;
5117         return 0;
5118 }
5119
5120 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5121 {
5122         struct sk_security_struct *sksec;
5123
5124         sksec = kzalloc(sizeof(*sksec), priority);
5125         if (!sksec)
5126                 return -ENOMEM;
5127
5128         sksec->peer_sid = SECINITSID_UNLABELED;
5129         sksec->sid = SECINITSID_UNLABELED;
5130         sksec->sclass = SECCLASS_SOCKET;
5131         selinux_netlbl_sk_security_reset(sksec);
5132         sk->sk_security = sksec;
5133
5134         return 0;
5135 }
5136
5137 static void selinux_sk_free_security(struct sock *sk)
5138 {
5139         struct sk_security_struct *sksec = sk->sk_security;
5140
5141         sk->sk_security = NULL;
5142         selinux_netlbl_sk_security_free(sksec);
5143         kfree(sksec);
5144 }
5145
5146 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5147 {
5148         struct sk_security_struct *sksec = sk->sk_security;
5149         struct sk_security_struct *newsksec = newsk->sk_security;
5150
5151         newsksec->sid = sksec->sid;
5152         newsksec->peer_sid = sksec->peer_sid;
5153         newsksec->sclass = sksec->sclass;
5154
5155         selinux_netlbl_sk_security_reset(newsksec);
5156 }
5157
5158 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5159 {
5160         if (!sk)
5161                 *secid = SECINITSID_ANY_SOCKET;
5162         else {
5163                 struct sk_security_struct *sksec = sk->sk_security;
5164
5165                 *secid = sksec->sid;
5166         }
5167 }
5168
5169 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5170 {
5171         struct inode_security_struct *isec =
5172                 inode_security_novalidate(SOCK_INODE(parent));
5173         struct sk_security_struct *sksec = sk->sk_security;
5174
5175         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5176             sk->sk_family == PF_UNIX)
5177                 isec->sid = sksec->sid;
5178         sksec->sclass = isec->sclass;
5179 }
5180
5181 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5182  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5183  * already present).
5184  */
5185 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5186                                       struct sk_buff *skb)
5187 {
5188         struct sk_security_struct *sksec = ep->base.sk->sk_security;
5189         struct common_audit_data ad;
5190         struct lsm_network_audit net = {0,};
5191         u8 peerlbl_active;
5192         u32 peer_sid = SECINITSID_UNLABELED;
5193         u32 conn_sid;
5194         int err = 0;
5195
5196         if (!selinux_policycap_extsockclass())
5197                 return 0;
5198
5199         peerlbl_active = selinux_peerlbl_enabled();
5200
5201         if (peerlbl_active) {
5202                 /* This will return peer_sid = SECSID_NULL if there are
5203                  * no peer labels, see security_net_peersid_resolve().
5204                  */
5205                 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5206                                               &peer_sid);
5207                 if (err)
5208                         return err;
5209
5210                 if (peer_sid == SECSID_NULL)
5211                         peer_sid = SECINITSID_UNLABELED;
5212         }
5213
5214         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5215                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5216
5217                 /* Here as first association on socket. As the peer SID
5218                  * was allowed by peer recv (and the netif/node checks),
5219                  * then it is approved by policy and used as the primary
5220                  * peer SID for getpeercon(3).
5221                  */
5222                 sksec->peer_sid = peer_sid;
5223         } else if  (sksec->peer_sid != peer_sid) {
5224                 /* Other association peer SIDs are checked to enforce
5225                  * consistency among the peer SIDs.
5226                  */
5227                 ad.type = LSM_AUDIT_DATA_NET;
5228                 ad.u.net = &net;
5229                 ad.u.net->sk = ep->base.sk;
5230                 err = avc_has_perm(&selinux_state,
5231                                    sksec->peer_sid, peer_sid, sksec->sclass,
5232                                    SCTP_SOCKET__ASSOCIATION, &ad);
5233                 if (err)
5234                         return err;
5235         }
5236
5237         /* Compute the MLS component for the connection and store
5238          * the information in ep. This will be used by SCTP TCP type
5239          * sockets and peeled off connections as they cause a new
5240          * socket to be generated. selinux_sctp_sk_clone() will then
5241          * plug this into the new socket.
5242          */
5243         err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5244         if (err)
5245                 return err;
5246
5247         ep->secid = conn_sid;
5248         ep->peer_secid = peer_sid;
5249
5250         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5251         return selinux_netlbl_sctp_assoc_request(ep, skb);
5252 }
5253
5254 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5255  * based on their @optname.
5256  */
5257 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5258                                      struct sockaddr *address,
5259                                      int addrlen)
5260 {
5261         int len, err = 0, walk_size = 0;
5262         void *addr_buf;
5263         struct sockaddr *addr;
5264         struct socket *sock;
5265
5266         if (!selinux_policycap_extsockclass())
5267                 return 0;
5268
5269         /* Process one or more addresses that may be IPv4 or IPv6 */
5270         sock = sk->sk_socket;
5271         addr_buf = address;
5272
5273         while (walk_size < addrlen) {
5274                 if (walk_size + sizeof(sa_family_t) > addrlen)
5275                         return -EINVAL;
5276
5277                 addr = addr_buf;
5278                 switch (addr->sa_family) {
5279                 case AF_UNSPEC:
5280                 case AF_INET:
5281                         len = sizeof(struct sockaddr_in);
5282                         break;
5283                 case AF_INET6:
5284                         len = sizeof(struct sockaddr_in6);
5285                         break;
5286                 default:
5287                         return -EINVAL;
5288                 }
5289
5290                 if (walk_size + len > addrlen)
5291                         return -EINVAL;
5292
5293                 err = -EINVAL;
5294                 switch (optname) {
5295                 /* Bind checks */
5296                 case SCTP_PRIMARY_ADDR:
5297                 case SCTP_SET_PEER_PRIMARY_ADDR:
5298                 case SCTP_SOCKOPT_BINDX_ADD:
5299                         err = selinux_socket_bind(sock, addr, len);
5300                         break;
5301                 /* Connect checks */
5302                 case SCTP_SOCKOPT_CONNECTX:
5303                 case SCTP_PARAM_SET_PRIMARY:
5304                 case SCTP_PARAM_ADD_IP:
5305                 case SCTP_SENDMSG_CONNECT:
5306                         err = selinux_socket_connect_helper(sock, addr, len);
5307                         if (err)
5308                                 return err;
5309
5310                         /* As selinux_sctp_bind_connect() is called by the
5311                          * SCTP protocol layer, the socket is already locked,
5312                          * therefore selinux_netlbl_socket_connect_locked() is
5313                          * is called here. The situations handled are:
5314                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5315                          * whenever a new IP address is added or when a new
5316                          * primary address is selected.
5317                          * Note that an SCTP connect(2) call happens before
5318                          * the SCTP protocol layer and is handled via
5319                          * selinux_socket_connect().
5320                          */
5321                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5322                         break;
5323                 }
5324
5325                 if (err)
5326                         return err;
5327
5328                 addr_buf += len;
5329                 walk_size += len;
5330         }
5331
5332         return 0;
5333 }
5334
5335 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5336 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5337                                   struct sock *newsk)
5338 {
5339         struct sk_security_struct *sksec = sk->sk_security;
5340         struct sk_security_struct *newsksec = newsk->sk_security;
5341
5342         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5343          * the non-sctp clone version.
5344          */
5345         if (!selinux_policycap_extsockclass())
5346                 return selinux_sk_clone_security(sk, newsk);
5347
5348         newsksec->sid = ep->secid;
5349         newsksec->peer_sid = ep->peer_secid;
5350         newsksec->sclass = sksec->sclass;
5351         selinux_netlbl_sctp_sk_clone(sk, newsk);
5352 }
5353
5354 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5355                                      struct request_sock *req)
5356 {
5357         struct sk_security_struct *sksec = sk->sk_security;
5358         int err;
5359         u16 family = req->rsk_ops->family;
5360         u32 connsid;
5361         u32 peersid;
5362
5363         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5364         if (err)
5365                 return err;
5366         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5367         if (err)
5368                 return err;
5369         req->secid = connsid;
5370         req->peer_secid = peersid;
5371
5372         return selinux_netlbl_inet_conn_request(req, family);
5373 }
5374
5375 static void selinux_inet_csk_clone(struct sock *newsk,
5376                                    const struct request_sock *req)
5377 {
5378         struct sk_security_struct *newsksec = newsk->sk_security;
5379
5380         newsksec->sid = req->secid;
5381         newsksec->peer_sid = req->peer_secid;
5382         /* NOTE: Ideally, we should also get the isec->sid for the
5383            new socket in sync, but we don't have the isec available yet.
5384            So we will wait until sock_graft to do it, by which
5385            time it will have been created and available. */
5386
5387         /* We don't need to take any sort of lock here as we are the only
5388          * thread with access to newsksec */
5389         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5390 }
5391
5392 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5393 {
5394         u16 family = sk->sk_family;
5395         struct sk_security_struct *sksec = sk->sk_security;
5396
5397         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5398         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5399                 family = PF_INET;
5400
5401         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5402 }
5403
5404 static int selinux_secmark_relabel_packet(u32 sid)
5405 {
5406         const struct task_security_struct *__tsec;
5407         u32 tsid;
5408
5409         __tsec = selinux_cred(current_cred());
5410         tsid = __tsec->sid;
5411
5412         return avc_has_perm(&selinux_state,
5413                             tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5414                             NULL);
5415 }
5416
5417 static void selinux_secmark_refcount_inc(void)
5418 {
5419         atomic_inc(&selinux_secmark_refcount);
5420 }
5421
5422 static void selinux_secmark_refcount_dec(void)
5423 {
5424         atomic_dec(&selinux_secmark_refcount);
5425 }
5426
5427 static void selinux_req_classify_flow(const struct request_sock *req,
5428                                       struct flowi *fl)
5429 {
5430         fl->flowi_secid = req->secid;
5431 }
5432
5433 static int selinux_tun_dev_alloc_security(void **security)
5434 {
5435         struct tun_security_struct *tunsec;
5436
5437         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5438         if (!tunsec)
5439                 return -ENOMEM;
5440         tunsec->sid = current_sid();
5441
5442         *security = tunsec;
5443         return 0;
5444 }
5445
5446 static void selinux_tun_dev_free_security(void *security)
5447 {
5448         kfree(security);
5449 }
5450
5451 static int selinux_tun_dev_create(void)
5452 {
5453         u32 sid = current_sid();
5454
5455         /* we aren't taking into account the "sockcreate" SID since the socket
5456          * that is being created here is not a socket in the traditional sense,
5457          * instead it is a private sock, accessible only to the kernel, and
5458          * representing a wide range of network traffic spanning multiple
5459          * connections unlike traditional sockets - check the TUN driver to
5460          * get a better understanding of why this socket is special */
5461
5462         return avc_has_perm(&selinux_state,
5463                             sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5464                             NULL);
5465 }
5466
5467 static int selinux_tun_dev_attach_queue(void *security)
5468 {
5469         struct tun_security_struct *tunsec = security;
5470
5471         return avc_has_perm(&selinux_state,
5472                             current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5473                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5474 }
5475
5476 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5477 {
5478         struct tun_security_struct *tunsec = security;
5479         struct sk_security_struct *sksec = sk->sk_security;
5480
5481         /* we don't currently perform any NetLabel based labeling here and it
5482          * isn't clear that we would want to do so anyway; while we could apply
5483          * labeling without the support of the TUN user the resulting labeled
5484          * traffic from the other end of the connection would almost certainly
5485          * cause confusion to the TUN user that had no idea network labeling
5486          * protocols were being used */
5487
5488         sksec->sid = tunsec->sid;
5489         sksec->sclass = SECCLASS_TUN_SOCKET;
5490
5491         return 0;
5492 }
5493
5494 static int selinux_tun_dev_open(void *security)
5495 {
5496         struct tun_security_struct *tunsec = security;
5497         u32 sid = current_sid();
5498         int err;
5499
5500         err = avc_has_perm(&selinux_state,
5501                            sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5502                            TUN_SOCKET__RELABELFROM, NULL);
5503         if (err)
5504                 return err;
5505         err = avc_has_perm(&selinux_state,
5506                            sid, sid, SECCLASS_TUN_SOCKET,
5507                            TUN_SOCKET__RELABELTO, NULL);
5508         if (err)
5509                 return err;
5510         tunsec->sid = sid;
5511
5512         return 0;
5513 }
5514
5515 #ifdef CONFIG_NETFILTER
5516
5517 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5518                                        const struct net_device *indev,
5519                                        u16 family)
5520 {
5521         int err;
5522         char *addrp;
5523         u32 peer_sid;
5524         struct common_audit_data ad;
5525         struct lsm_network_audit net = {0,};
5526         u8 secmark_active;
5527         u8 netlbl_active;
5528         u8 peerlbl_active;
5529
5530         if (!selinux_policycap_netpeer())
5531                 return NF_ACCEPT;
5532
5533         secmark_active = selinux_secmark_enabled();
5534         netlbl_active = netlbl_enabled();
5535         peerlbl_active = selinux_peerlbl_enabled();
5536         if (!secmark_active && !peerlbl_active)
5537                 return NF_ACCEPT;
5538
5539         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5540                 return NF_DROP;
5541
5542         ad.type = LSM_AUDIT_DATA_NET;
5543         ad.u.net = &net;
5544         ad.u.net->netif = indev->ifindex;
5545         ad.u.net->family = family;
5546         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5547                 return NF_DROP;
5548
5549         if (peerlbl_active) {
5550                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5551                                                addrp, family, peer_sid, &ad);
5552                 if (err) {
5553                         selinux_netlbl_err(skb, family, err, 1);
5554                         return NF_DROP;
5555                 }
5556         }
5557
5558         if (secmark_active)
5559                 if (avc_has_perm(&selinux_state,
5560                                  peer_sid, skb->secmark,
5561                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5562                         return NF_DROP;
5563
5564         if (netlbl_active)
5565                 /* we do this in the FORWARD path and not the POST_ROUTING
5566                  * path because we want to make sure we apply the necessary
5567                  * labeling before IPsec is applied so we can leverage AH
5568                  * protection */
5569                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5570                         return NF_DROP;
5571
5572         return NF_ACCEPT;
5573 }
5574
5575 static unsigned int selinux_ipv4_forward(void *priv,
5576                                          struct sk_buff *skb,
5577                                          const struct nf_hook_state *state)
5578 {
5579         return selinux_ip_forward(skb, state->in, PF_INET);
5580 }
5581
5582 #if IS_ENABLED(CONFIG_IPV6)
5583 static unsigned int selinux_ipv6_forward(void *priv,
5584                                          struct sk_buff *skb,
5585                                          const struct nf_hook_state *state)
5586 {
5587         return selinux_ip_forward(skb, state->in, PF_INET6);
5588 }
5589 #endif  /* IPV6 */
5590
5591 static unsigned int selinux_ip_output(struct sk_buff *skb,
5592                                       u16 family)
5593 {
5594         struct sock *sk;
5595         u32 sid;
5596
5597         if (!netlbl_enabled())
5598                 return NF_ACCEPT;
5599
5600         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5601          * because we want to make sure we apply the necessary labeling
5602          * before IPsec is applied so we can leverage AH protection */
5603         sk = skb->sk;
5604         if (sk) {
5605                 struct sk_security_struct *sksec;
5606
5607                 if (sk_listener(sk))
5608                         /* if the socket is the listening state then this
5609                          * packet is a SYN-ACK packet which means it needs to
5610                          * be labeled based on the connection/request_sock and
5611                          * not the parent socket.  unfortunately, we can't
5612                          * lookup the request_sock yet as it isn't queued on
5613                          * the parent socket until after the SYN-ACK is sent.
5614                          * the "solution" is to simply pass the packet as-is
5615                          * as any IP option based labeling should be copied
5616                          * from the initial connection request (in the IP
5617                          * layer).  it is far from ideal, but until we get a
5618                          * security label in the packet itself this is the
5619                          * best we can do. */
5620                         return NF_ACCEPT;
5621
5622                 /* standard practice, label using the parent socket */
5623                 sksec = sk->sk_security;
5624                 sid = sksec->sid;
5625         } else
5626                 sid = SECINITSID_KERNEL;
5627         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5628                 return NF_DROP;
5629
5630         return NF_ACCEPT;
5631 }
5632
5633 static unsigned int selinux_ipv4_output(void *priv,
5634                                         struct sk_buff *skb,
5635                                         const struct nf_hook_state *state)
5636 {
5637         return selinux_ip_output(skb, PF_INET);
5638 }
5639
5640 #if IS_ENABLED(CONFIG_IPV6)
5641 static unsigned int selinux_ipv6_output(void *priv,
5642                                         struct sk_buff *skb,
5643                                         const struct nf_hook_state *state)
5644 {
5645         return selinux_ip_output(skb, PF_INET6);
5646 }
5647 #endif  /* IPV6 */
5648
5649 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5650                                                 int ifindex,
5651                                                 u16 family)
5652 {
5653         struct sock *sk = skb_to_full_sk(skb);
5654         struct sk_security_struct *sksec;
5655         struct common_audit_data ad;
5656         struct lsm_network_audit net = {0,};
5657         char *addrp;
5658         u8 proto;
5659
5660         if (sk == NULL)
5661                 return NF_ACCEPT;
5662         sksec = sk->sk_security;
5663
5664         ad.type = LSM_AUDIT_DATA_NET;
5665         ad.u.net = &net;
5666         ad.u.net->netif = ifindex;
5667         ad.u.net->family = family;
5668         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5669                 return NF_DROP;
5670
5671         if (selinux_secmark_enabled())
5672                 if (avc_has_perm(&selinux_state,
5673                                  sksec->sid, skb->secmark,
5674                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5675                         return NF_DROP_ERR(-ECONNREFUSED);
5676
5677         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5678                 return NF_DROP_ERR(-ECONNREFUSED);
5679
5680         return NF_ACCEPT;
5681 }
5682
5683 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5684                                          const struct net_device *outdev,
5685                                          u16 family)
5686 {
5687         u32 secmark_perm;
5688         u32 peer_sid;
5689         int ifindex = outdev->ifindex;
5690         struct sock *sk;
5691         struct common_audit_data ad;
5692         struct lsm_network_audit net = {0,};
5693         char *addrp;
5694         u8 secmark_active;
5695         u8 peerlbl_active;
5696
5697         /* If any sort of compatibility mode is enabled then handoff processing
5698          * to the selinux_ip_postroute_compat() function to deal with the
5699          * special handling.  We do this in an attempt to keep this function
5700          * as fast and as clean as possible. */
5701         if (!selinux_policycap_netpeer())
5702                 return selinux_ip_postroute_compat(skb, ifindex, family);
5703
5704         secmark_active = selinux_secmark_enabled();
5705         peerlbl_active = selinux_peerlbl_enabled();
5706         if (!secmark_active && !peerlbl_active)
5707                 return NF_ACCEPT;
5708
5709         sk = skb_to_full_sk(skb);
5710
5711 #ifdef CONFIG_XFRM
5712         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5713          * packet transformation so allow the packet to pass without any checks
5714          * since we'll have another chance to perform access control checks
5715          * when the packet is on it's final way out.
5716          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5717          *       is NULL, in this case go ahead and apply access control.
5718          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5719          *       TCP listening state we cannot wait until the XFRM processing
5720          *       is done as we will miss out on the SA label if we do;
5721          *       unfortunately, this means more work, but it is only once per
5722          *       connection. */
5723         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5724             !(sk && sk_listener(sk)))
5725                 return NF_ACCEPT;
5726 #endif
5727
5728         if (sk == NULL) {
5729                 /* Without an associated socket the packet is either coming
5730                  * from the kernel or it is being forwarded; check the packet
5731                  * to determine which and if the packet is being forwarded
5732                  * query the packet directly to determine the security label. */
5733                 if (skb->skb_iif) {
5734                         secmark_perm = PACKET__FORWARD_OUT;
5735                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5736                                 return NF_DROP;
5737                 } else {
5738                         secmark_perm = PACKET__SEND;
5739                         peer_sid = SECINITSID_KERNEL;
5740                 }
5741         } else if (sk_listener(sk)) {
5742                 /* Locally generated packet but the associated socket is in the
5743                  * listening state which means this is a SYN-ACK packet.  In
5744                  * this particular case the correct security label is assigned
5745                  * to the connection/request_sock but unfortunately we can't
5746                  * query the request_sock as it isn't queued on the parent
5747                  * socket until after the SYN-ACK packet is sent; the only
5748                  * viable choice is to regenerate the label like we do in
5749                  * selinux_inet_conn_request().  See also selinux_ip_output()
5750                  * for similar problems. */
5751                 u32 skb_sid;
5752                 struct sk_security_struct *sksec;
5753
5754                 sksec = sk->sk_security;
5755                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5756                         return NF_DROP;
5757                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5758                  * and the packet has been through at least one XFRM
5759                  * transformation then we must be dealing with the "final"
5760                  * form of labeled IPsec packet; since we've already applied
5761                  * all of our access controls on this packet we can safely
5762                  * pass the packet. */
5763                 if (skb_sid == SECSID_NULL) {
5764                         switch (family) {
5765                         case PF_INET:
5766                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5767                                         return NF_ACCEPT;
5768                                 break;
5769                         case PF_INET6:
5770                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5771                                         return NF_ACCEPT;
5772                                 break;
5773                         default:
5774                                 return NF_DROP_ERR(-ECONNREFUSED);
5775                         }
5776                 }
5777                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5778                         return NF_DROP;
5779                 secmark_perm = PACKET__SEND;
5780         } else {
5781                 /* Locally generated packet, fetch the security label from the
5782                  * associated socket. */
5783                 struct sk_security_struct *sksec = sk->sk_security;
5784                 peer_sid = sksec->sid;
5785                 secmark_perm = PACKET__SEND;
5786         }
5787
5788         ad.type = LSM_AUDIT_DATA_NET;
5789         ad.u.net = &net;
5790         ad.u.net->netif = ifindex;
5791         ad.u.net->family = family;
5792         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5793                 return NF_DROP;
5794
5795         if (secmark_active)
5796                 if (avc_has_perm(&selinux_state,
5797                                  peer_sid, skb->secmark,
5798                                  SECCLASS_PACKET, secmark_perm, &ad))
5799                         return NF_DROP_ERR(-ECONNREFUSED);
5800
5801         if (peerlbl_active) {
5802                 u32 if_sid;
5803                 u32 node_sid;
5804
5805                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5806                         return NF_DROP;
5807                 if (avc_has_perm(&selinux_state,
5808                                  peer_sid, if_sid,
5809                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5810                         return NF_DROP_ERR(-ECONNREFUSED);
5811
5812                 if (sel_netnode_sid(addrp, family, &node_sid))
5813                         return NF_DROP;
5814                 if (avc_has_perm(&selinux_state,
5815                                  peer_sid, node_sid,
5816                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5817                         return NF_DROP_ERR(-ECONNREFUSED);
5818         }
5819
5820         return NF_ACCEPT;
5821 }
5822
5823 static unsigned int selinux_ipv4_postroute(void *priv,
5824                                            struct sk_buff *skb,
5825                                            const struct nf_hook_state *state)
5826 {
5827         return selinux_ip_postroute(skb, state->out, PF_INET);
5828 }
5829
5830 #if IS_ENABLED(CONFIG_IPV6)
5831 static unsigned int selinux_ipv6_postroute(void *priv,
5832                                            struct sk_buff *skb,
5833                                            const struct nf_hook_state *state)
5834 {
5835         return selinux_ip_postroute(skb, state->out, PF_INET6);
5836 }
5837 #endif  /* IPV6 */
5838
5839 #endif  /* CONFIG_NETFILTER */
5840
5841 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5842 {
5843         int rc = 0;
5844         unsigned int msg_len;
5845         unsigned int data_len = skb->len;
5846         unsigned char *data = skb->data;
5847         struct nlmsghdr *nlh;
5848         struct sk_security_struct *sksec = sk->sk_security;
5849         u16 sclass = sksec->sclass;
5850         u32 perm;
5851
5852         while (data_len >= nlmsg_total_size(0)) {
5853                 nlh = (struct nlmsghdr *)data;
5854
5855                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5856                  *       users which means we can't reject skb's with bogus
5857                  *       length fields; our solution is to follow what
5858                  *       netlink_rcv_skb() does and simply skip processing at
5859                  *       messages with length fields that are clearly junk
5860                  */
5861                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5862                         return 0;
5863
5864                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5865                 if (rc == 0) {
5866                         rc = sock_has_perm(sk, perm);
5867                         if (rc)
5868                                 return rc;
5869                 } else if (rc == -EINVAL) {
5870                         /* -EINVAL is a missing msg/perm mapping */
5871                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5872                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5873                                 " pid=%d comm=%s\n",
5874                                 sk->sk_protocol, nlh->nlmsg_type,
5875                                 secclass_map[sclass - 1].name,
5876                                 task_pid_nr(current), current->comm);
5877                         if (enforcing_enabled(&selinux_state) &&
5878                             !security_get_allow_unknown(&selinux_state))
5879                                 return rc;
5880                         rc = 0;
5881                 } else if (rc == -ENOENT) {
5882                         /* -ENOENT is a missing socket/class mapping, ignore */
5883                         rc = 0;
5884                 } else {
5885                         return rc;
5886                 }
5887
5888                 /* move to the next message after applying netlink padding */
5889                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5890                 if (msg_len >= data_len)
5891                         return 0;
5892                 data_len -= msg_len;
5893                 data += msg_len;
5894         }
5895
5896         return rc;
5897 }
5898
5899 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5900 {
5901         isec->sclass = sclass;
5902         isec->sid = current_sid();
5903 }
5904
5905 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5906                         u32 perms)
5907 {
5908         struct ipc_security_struct *isec;
5909         struct common_audit_data ad;
5910         u32 sid = current_sid();
5911
5912         isec = selinux_ipc(ipc_perms);
5913
5914         ad.type = LSM_AUDIT_DATA_IPC;
5915         ad.u.ipc_id = ipc_perms->key;
5916
5917         return avc_has_perm(&selinux_state,
5918                             sid, isec->sid, isec->sclass, perms, &ad);
5919 }
5920
5921 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5922 {
5923         struct msg_security_struct *msec;
5924
5925         msec = selinux_msg_msg(msg);
5926         msec->sid = SECINITSID_UNLABELED;
5927
5928         return 0;
5929 }
5930
5931 /* message queue security operations */
5932 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5933 {
5934         struct ipc_security_struct *isec;
5935         struct common_audit_data ad;
5936         u32 sid = current_sid();
5937         int rc;
5938
5939         isec = selinux_ipc(msq);
5940         ipc_init_security(isec, SECCLASS_MSGQ);
5941
5942         ad.type = LSM_AUDIT_DATA_IPC;
5943         ad.u.ipc_id = msq->key;
5944
5945         rc = avc_has_perm(&selinux_state,
5946                           sid, isec->sid, SECCLASS_MSGQ,
5947                           MSGQ__CREATE, &ad);
5948         return rc;
5949 }
5950
5951 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5952 {
5953         struct ipc_security_struct *isec;
5954         struct common_audit_data ad;
5955         u32 sid = current_sid();
5956
5957         isec = selinux_ipc(msq);
5958
5959         ad.type = LSM_AUDIT_DATA_IPC;
5960         ad.u.ipc_id = msq->key;
5961
5962         return avc_has_perm(&selinux_state,
5963                             sid, isec->sid, SECCLASS_MSGQ,
5964                             MSGQ__ASSOCIATE, &ad);
5965 }
5966
5967 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5968 {
5969         int err;
5970         int perms;
5971
5972         switch (cmd) {
5973         case IPC_INFO:
5974         case MSG_INFO:
5975                 /* No specific object, just general system-wide information. */
5976                 return avc_has_perm(&selinux_state,
5977                                     current_sid(), SECINITSID_KERNEL,
5978                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5979         case IPC_STAT:
5980         case MSG_STAT:
5981         case MSG_STAT_ANY:
5982                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5983                 break;
5984         case IPC_SET:
5985                 perms = MSGQ__SETATTR;
5986                 break;
5987         case IPC_RMID:
5988                 perms = MSGQ__DESTROY;
5989                 break;
5990         default:
5991                 return 0;
5992         }
5993
5994         err = ipc_has_perm(msq, perms);
5995         return err;
5996 }
5997
5998 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5999 {
6000         struct ipc_security_struct *isec;
6001         struct msg_security_struct *msec;
6002         struct common_audit_data ad;
6003         u32 sid = current_sid();
6004         int rc;
6005
6006         isec = selinux_ipc(msq);
6007         msec = selinux_msg_msg(msg);
6008
6009         /*
6010          * First time through, need to assign label to the message
6011          */
6012         if (msec->sid == SECINITSID_UNLABELED) {
6013                 /*
6014                  * Compute new sid based on current process and
6015                  * message queue this message will be stored in
6016                  */
6017                 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6018                                              SECCLASS_MSG, NULL, &msec->sid);
6019                 if (rc)
6020                         return rc;
6021         }
6022
6023         ad.type = LSM_AUDIT_DATA_IPC;
6024         ad.u.ipc_id = msq->key;
6025
6026         /* Can this process write to the queue? */
6027         rc = avc_has_perm(&selinux_state,
6028                           sid, isec->sid, SECCLASS_MSGQ,
6029                           MSGQ__WRITE, &ad);
6030         if (!rc)
6031                 /* Can this process send the message */
6032                 rc = avc_has_perm(&selinux_state,
6033                                   sid, msec->sid, SECCLASS_MSG,
6034                                   MSG__SEND, &ad);
6035         if (!rc)
6036                 /* Can the message be put in the queue? */
6037                 rc = avc_has_perm(&selinux_state,
6038                                   msec->sid, isec->sid, SECCLASS_MSGQ,
6039                                   MSGQ__ENQUEUE, &ad);
6040
6041         return rc;
6042 }
6043
6044 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6045                                     struct task_struct *target,
6046                                     long type, int mode)
6047 {
6048         struct ipc_security_struct *isec;
6049         struct msg_security_struct *msec;
6050         struct common_audit_data ad;
6051         u32 sid = task_sid(target);
6052         int rc;
6053
6054         isec = selinux_ipc(msq);
6055         msec = selinux_msg_msg(msg);
6056
6057         ad.type = LSM_AUDIT_DATA_IPC;
6058         ad.u.ipc_id = msq->key;
6059
6060         rc = avc_has_perm(&selinux_state,
6061                           sid, isec->sid,
6062                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6063         if (!rc)
6064                 rc = avc_has_perm(&selinux_state,
6065                                   sid, msec->sid,
6066                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6067         return rc;
6068 }
6069
6070 /* Shared Memory security operations */
6071 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6072 {
6073         struct ipc_security_struct *isec;
6074         struct common_audit_data ad;
6075         u32 sid = current_sid();
6076         int rc;
6077
6078         isec = selinux_ipc(shp);
6079         ipc_init_security(isec, SECCLASS_SHM);
6080
6081         ad.type = LSM_AUDIT_DATA_IPC;
6082         ad.u.ipc_id = shp->key;
6083
6084         rc = avc_has_perm(&selinux_state,
6085                           sid, isec->sid, SECCLASS_SHM,
6086                           SHM__CREATE, &ad);
6087         return rc;
6088 }
6089
6090 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6091 {
6092         struct ipc_security_struct *isec;
6093         struct common_audit_data ad;
6094         u32 sid = current_sid();
6095
6096         isec = selinux_ipc(shp);
6097
6098         ad.type = LSM_AUDIT_DATA_IPC;
6099         ad.u.ipc_id = shp->key;
6100
6101         return avc_has_perm(&selinux_state,
6102                             sid, isec->sid, SECCLASS_SHM,
6103                             SHM__ASSOCIATE, &ad);
6104 }
6105
6106 /* Note, at this point, shp is locked down */
6107 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6108 {
6109         int perms;
6110         int err;
6111
6112         switch (cmd) {
6113         case IPC_INFO:
6114         case SHM_INFO:
6115                 /* No specific object, just general system-wide information. */
6116                 return avc_has_perm(&selinux_state,
6117                                     current_sid(), SECINITSID_KERNEL,
6118                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6119         case IPC_STAT:
6120         case SHM_STAT:
6121         case SHM_STAT_ANY:
6122                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6123                 break;
6124         case IPC_SET:
6125                 perms = SHM__SETATTR;
6126                 break;
6127         case SHM_LOCK:
6128         case SHM_UNLOCK:
6129                 perms = SHM__LOCK;
6130                 break;
6131         case IPC_RMID:
6132                 perms = SHM__DESTROY;
6133                 break;
6134         default:
6135                 return 0;
6136         }
6137
6138         err = ipc_has_perm(shp, perms);
6139         return err;
6140 }
6141
6142 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6143                              char __user *shmaddr, int shmflg)
6144 {
6145         u32 perms;
6146
6147         if (shmflg & SHM_RDONLY)
6148                 perms = SHM__READ;
6149         else
6150                 perms = SHM__READ | SHM__WRITE;
6151
6152         return ipc_has_perm(shp, perms);
6153 }
6154
6155 /* Semaphore security operations */
6156 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6157 {
6158         struct ipc_security_struct *isec;
6159         struct common_audit_data ad;
6160         u32 sid = current_sid();
6161         int rc;
6162
6163         isec = selinux_ipc(sma);
6164         ipc_init_security(isec, SECCLASS_SEM);
6165
6166         ad.type = LSM_AUDIT_DATA_IPC;
6167         ad.u.ipc_id = sma->key;
6168
6169         rc = avc_has_perm(&selinux_state,
6170                           sid, isec->sid, SECCLASS_SEM,
6171                           SEM__CREATE, &ad);
6172         return rc;
6173 }
6174
6175 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6176 {
6177         struct ipc_security_struct *isec;
6178         struct common_audit_data ad;
6179         u32 sid = current_sid();
6180
6181         isec = selinux_ipc(sma);
6182
6183         ad.type = LSM_AUDIT_DATA_IPC;
6184         ad.u.ipc_id = sma->key;
6185
6186         return avc_has_perm(&selinux_state,
6187                             sid, isec->sid, SECCLASS_SEM,
6188                             SEM__ASSOCIATE, &ad);
6189 }
6190
6191 /* Note, at this point, sma is locked down */
6192 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6193 {
6194         int err;
6195         u32 perms;
6196
6197         switch (cmd) {
6198         case IPC_INFO:
6199         case SEM_INFO:
6200                 /* No specific object, just general system-wide information. */
6201                 return avc_has_perm(&selinux_state,
6202                                     current_sid(), SECINITSID_KERNEL,
6203                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6204         case GETPID:
6205         case GETNCNT:
6206         case GETZCNT:
6207                 perms = SEM__GETATTR;
6208                 break;
6209         case GETVAL:
6210         case GETALL:
6211                 perms = SEM__READ;
6212                 break;
6213         case SETVAL:
6214         case SETALL:
6215                 perms = SEM__WRITE;
6216                 break;
6217         case IPC_RMID:
6218                 perms = SEM__DESTROY;
6219                 break;
6220         case IPC_SET:
6221                 perms = SEM__SETATTR;
6222                 break;
6223         case IPC_STAT:
6224         case SEM_STAT:
6225         case SEM_STAT_ANY:
6226                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6227                 break;
6228         default:
6229                 return 0;
6230         }
6231
6232         err = ipc_has_perm(sma, perms);
6233         return err;
6234 }
6235
6236 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6237                              struct sembuf *sops, unsigned nsops, int alter)
6238 {
6239         u32 perms;
6240
6241         if (alter)
6242                 perms = SEM__READ | SEM__WRITE;
6243         else
6244                 perms = SEM__READ;
6245
6246         return ipc_has_perm(sma, perms);
6247 }
6248
6249 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6250 {
6251         u32 av = 0;
6252
6253         av = 0;
6254         if (flag & S_IRUGO)
6255                 av |= IPC__UNIX_READ;
6256         if (flag & S_IWUGO)
6257                 av |= IPC__UNIX_WRITE;
6258
6259         if (av == 0)
6260                 return 0;
6261
6262         return ipc_has_perm(ipcp, av);
6263 }
6264
6265 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6266 {
6267         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6268         *secid = isec->sid;
6269 }
6270
6271 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6272 {
6273         if (inode)
6274                 inode_doinit_with_dentry(inode, dentry);
6275 }
6276
6277 static int selinux_getprocattr(struct task_struct *p,
6278                                char *name, char **value)
6279 {
6280         const struct task_security_struct *__tsec;
6281         u32 sid;
6282         int error;
6283         unsigned len;
6284
6285         rcu_read_lock();
6286         __tsec = selinux_cred(__task_cred(p));
6287
6288         if (current != p) {
6289                 error = avc_has_perm(&selinux_state,
6290                                      current_sid(), __tsec->sid,
6291                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6292                 if (error)
6293                         goto bad;
6294         }
6295
6296         if (!strcmp(name, "current"))
6297                 sid = __tsec->sid;
6298         else if (!strcmp(name, "prev"))
6299                 sid = __tsec->osid;
6300         else if (!strcmp(name, "exec"))
6301                 sid = __tsec->exec_sid;
6302         else if (!strcmp(name, "fscreate"))
6303                 sid = __tsec->create_sid;
6304         else if (!strcmp(name, "keycreate"))
6305                 sid = __tsec->keycreate_sid;
6306         else if (!strcmp(name, "sockcreate"))
6307                 sid = __tsec->sockcreate_sid;
6308         else {
6309                 error = -EINVAL;
6310                 goto bad;
6311         }
6312         rcu_read_unlock();
6313
6314         if (!sid)
6315                 return 0;
6316
6317         error = security_sid_to_context(&selinux_state, sid, value, &len);
6318         if (error)
6319                 return error;
6320         return len;
6321
6322 bad:
6323         rcu_read_unlock();
6324         return error;
6325 }
6326
6327 static int selinux_setprocattr(const char *name, void *value, size_t size)
6328 {
6329         struct task_security_struct *tsec;
6330         struct cred *new;
6331         u32 mysid = current_sid(), sid = 0, ptsid;
6332         int error;
6333         char *str = value;
6334
6335         /*
6336          * Basic control over ability to set these attributes at all.
6337          */
6338         if (!strcmp(name, "exec"))
6339                 error = avc_has_perm(&selinux_state,
6340                                      mysid, mysid, SECCLASS_PROCESS,
6341                                      PROCESS__SETEXEC, NULL);
6342         else if (!strcmp(name, "fscreate"))
6343                 error = avc_has_perm(&selinux_state,
6344                                      mysid, mysid, SECCLASS_PROCESS,
6345                                      PROCESS__SETFSCREATE, NULL);
6346         else if (!strcmp(name, "keycreate"))
6347                 error = avc_has_perm(&selinux_state,
6348                                      mysid, mysid, SECCLASS_PROCESS,
6349                                      PROCESS__SETKEYCREATE, NULL);
6350         else if (!strcmp(name, "sockcreate"))
6351                 error = avc_has_perm(&selinux_state,
6352                                      mysid, mysid, SECCLASS_PROCESS,
6353                                      PROCESS__SETSOCKCREATE, NULL);
6354         else if (!strcmp(name, "current"))
6355                 error = avc_has_perm(&selinux_state,
6356                                      mysid, mysid, SECCLASS_PROCESS,
6357                                      PROCESS__SETCURRENT, NULL);
6358         else
6359                 error = -EINVAL;
6360         if (error)
6361                 return error;
6362
6363         /* Obtain a SID for the context, if one was specified. */
6364         if (size && str[0] && str[0] != '\n') {
6365                 if (str[size-1] == '\n') {
6366                         str[size-1] = 0;
6367                         size--;
6368                 }
6369                 error = security_context_to_sid(&selinux_state, value, size,
6370                                                 &sid, GFP_KERNEL);
6371                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6372                         if (!has_cap_mac_admin(true)) {
6373                                 struct audit_buffer *ab;
6374                                 size_t audit_size;
6375
6376                                 /* We strip a nul only if it is at the end, otherwise the
6377                                  * context contains a nul and we should audit that */
6378                                 if (str[size - 1] == '\0')
6379                                         audit_size = size - 1;
6380                                 else
6381                                         audit_size = size;
6382                                 ab = audit_log_start(audit_context(),
6383                                                      GFP_ATOMIC,
6384                                                      AUDIT_SELINUX_ERR);
6385                                 audit_log_format(ab, "op=fscreate invalid_context=");
6386                                 audit_log_n_untrustedstring(ab, value, audit_size);
6387                                 audit_log_end(ab);
6388
6389                                 return error;
6390                         }
6391                         error = security_context_to_sid_force(
6392                                                       &selinux_state,
6393                                                       value, size, &sid);
6394                 }
6395                 if (error)
6396                         return error;
6397         }
6398
6399         new = prepare_creds();
6400         if (!new)
6401                 return -ENOMEM;
6402
6403         /* Permission checking based on the specified context is
6404            performed during the actual operation (execve,
6405            open/mkdir/...), when we know the full context of the
6406            operation.  See selinux_bprm_creds_for_exec for the execve
6407            checks and may_create for the file creation checks. The
6408            operation will then fail if the context is not permitted. */
6409         tsec = selinux_cred(new);
6410         if (!strcmp(name, "exec")) {
6411                 tsec->exec_sid = sid;
6412         } else if (!strcmp(name, "fscreate")) {
6413                 tsec->create_sid = sid;
6414         } else if (!strcmp(name, "keycreate")) {
6415                 if (sid) {
6416                         error = avc_has_perm(&selinux_state, mysid, sid,
6417                                              SECCLASS_KEY, KEY__CREATE, NULL);
6418                         if (error)
6419                                 goto abort_change;
6420                 }
6421                 tsec->keycreate_sid = sid;
6422         } else if (!strcmp(name, "sockcreate")) {
6423                 tsec->sockcreate_sid = sid;
6424         } else if (!strcmp(name, "current")) {
6425                 error = -EINVAL;
6426                 if (sid == 0)
6427                         goto abort_change;
6428
6429                 /* Only allow single threaded processes to change context */
6430                 error = -EPERM;
6431                 if (!current_is_single_threaded()) {
6432                         error = security_bounded_transition(&selinux_state,
6433                                                             tsec->sid, sid);
6434                         if (error)
6435                                 goto abort_change;
6436                 }
6437
6438                 /* Check permissions for the transition. */
6439                 error = avc_has_perm(&selinux_state,
6440                                      tsec->sid, sid, SECCLASS_PROCESS,
6441                                      PROCESS__DYNTRANSITION, NULL);
6442                 if (error)
6443                         goto abort_change;
6444
6445                 /* Check for ptracing, and update the task SID if ok.
6446                    Otherwise, leave SID unchanged and fail. */
6447                 ptsid = ptrace_parent_sid();
6448                 if (ptsid != 0) {
6449                         error = avc_has_perm(&selinux_state,
6450                                              ptsid, sid, SECCLASS_PROCESS,
6451                                              PROCESS__PTRACE, NULL);
6452                         if (error)
6453                                 goto abort_change;
6454                 }
6455
6456                 tsec->sid = sid;
6457         } else {
6458                 error = -EINVAL;
6459                 goto abort_change;
6460         }
6461
6462         commit_creds(new);
6463         return size;
6464
6465 abort_change:
6466         abort_creds(new);
6467         return error;
6468 }
6469
6470 static int selinux_ismaclabel(const char *name)
6471 {
6472         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6473 }
6474
6475 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6476 {
6477         return security_sid_to_context(&selinux_state, secid,
6478                                        secdata, seclen);
6479 }
6480
6481 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6482 {
6483         return security_context_to_sid(&selinux_state, secdata, seclen,
6484                                        secid, GFP_KERNEL);
6485 }
6486
6487 static void selinux_release_secctx(char *secdata, u32 seclen)
6488 {
6489         kfree(secdata);
6490 }
6491
6492 static void selinux_inode_invalidate_secctx(struct inode *inode)
6493 {
6494         struct inode_security_struct *isec = selinux_inode(inode);
6495
6496         spin_lock(&isec->lock);
6497         isec->initialized = LABEL_INVALID;
6498         spin_unlock(&isec->lock);
6499 }
6500
6501 /*
6502  *      called with inode->i_mutex locked
6503  */
6504 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6505 {
6506         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6507                                            ctx, ctxlen, 0);
6508         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6509         return rc == -EOPNOTSUPP ? 0 : rc;
6510 }
6511
6512 /*
6513  *      called with inode->i_mutex locked
6514  */
6515 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6516 {
6517         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6518 }
6519
6520 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6521 {
6522         int len = 0;
6523         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6524                                                 ctx, true);
6525         if (len < 0)
6526                 return len;
6527         *ctxlen = len;
6528         return 0;
6529 }
6530 #ifdef CONFIG_KEYS
6531
6532 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6533                              unsigned long flags)
6534 {
6535         const struct task_security_struct *tsec;
6536         struct key_security_struct *ksec;
6537
6538         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6539         if (!ksec)
6540                 return -ENOMEM;
6541
6542         tsec = selinux_cred(cred);
6543         if (tsec->keycreate_sid)
6544                 ksec->sid = tsec->keycreate_sid;
6545         else
6546                 ksec->sid = tsec->sid;
6547
6548         k->security = ksec;
6549         return 0;
6550 }
6551
6552 static void selinux_key_free(struct key *k)
6553 {
6554         struct key_security_struct *ksec = k->security;
6555
6556         k->security = NULL;
6557         kfree(ksec);
6558 }
6559
6560 static int selinux_key_permission(key_ref_t key_ref,
6561                                   const struct cred *cred,
6562                                   enum key_need_perm need_perm)
6563 {
6564         struct key *key;
6565         struct key_security_struct *ksec;
6566         u32 perm, sid;
6567
6568         switch (need_perm) {
6569         case KEY_NEED_VIEW:
6570                 perm = KEY__VIEW;
6571                 break;
6572         case KEY_NEED_READ:
6573                 perm = KEY__READ;
6574                 break;
6575         case KEY_NEED_WRITE:
6576                 perm = KEY__WRITE;
6577                 break;
6578         case KEY_NEED_SEARCH:
6579                 perm = KEY__SEARCH;
6580                 break;
6581         case KEY_NEED_LINK:
6582                 perm = KEY__LINK;
6583                 break;
6584         case KEY_NEED_SETATTR:
6585                 perm = KEY__SETATTR;
6586                 break;
6587         case KEY_NEED_UNLINK:
6588         case KEY_SYSADMIN_OVERRIDE:
6589         case KEY_AUTHTOKEN_OVERRIDE:
6590         case KEY_DEFER_PERM_CHECK:
6591                 return 0;
6592         default:
6593                 WARN_ON(1);
6594                 return -EPERM;
6595
6596         }
6597
6598         sid = cred_sid(cred);
6599         key = key_ref_to_ptr(key_ref);
6600         ksec = key->security;
6601
6602         return avc_has_perm(&selinux_state,
6603                             sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6604 }
6605
6606 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6607 {
6608         struct key_security_struct *ksec = key->security;
6609         char *context = NULL;
6610         unsigned len;
6611         int rc;
6612
6613         rc = security_sid_to_context(&selinux_state, ksec->sid,
6614                                      &context, &len);
6615         if (!rc)
6616                 rc = len;
6617         *_buffer = context;
6618         return rc;
6619 }
6620
6621 #ifdef CONFIG_KEY_NOTIFICATIONS
6622 static int selinux_watch_key(struct key *key)
6623 {
6624         struct key_security_struct *ksec = key->security;
6625         u32 sid = current_sid();
6626
6627         return avc_has_perm(&selinux_state,
6628                             sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6629 }
6630 #endif
6631 #endif
6632
6633 #ifdef CONFIG_SECURITY_INFINIBAND
6634 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6635 {
6636         struct common_audit_data ad;
6637         int err;
6638         u32 sid = 0;
6639         struct ib_security_struct *sec = ib_sec;
6640         struct lsm_ibpkey_audit ibpkey;
6641
6642         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6643         if (err)
6644                 return err;
6645
6646         ad.type = LSM_AUDIT_DATA_IBPKEY;
6647         ibpkey.subnet_prefix = subnet_prefix;
6648         ibpkey.pkey = pkey_val;
6649         ad.u.ibpkey = &ibpkey;
6650         return avc_has_perm(&selinux_state,
6651                             sec->sid, sid,
6652                             SECCLASS_INFINIBAND_PKEY,
6653                             INFINIBAND_PKEY__ACCESS, &ad);
6654 }
6655
6656 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6657                                             u8 port_num)
6658 {
6659         struct common_audit_data ad;
6660         int err;
6661         u32 sid = 0;
6662         struct ib_security_struct *sec = ib_sec;
6663         struct lsm_ibendport_audit ibendport;
6664
6665         err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6666                                       &sid);
6667
6668         if (err)
6669                 return err;
6670
6671         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6672         strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6673         ibendport.port = port_num;
6674         ad.u.ibendport = &ibendport;
6675         return avc_has_perm(&selinux_state,
6676                             sec->sid, sid,
6677                             SECCLASS_INFINIBAND_ENDPORT,
6678                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6679 }
6680
6681 static int selinux_ib_alloc_security(void **ib_sec)
6682 {
6683         struct ib_security_struct *sec;
6684
6685         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6686         if (!sec)
6687                 return -ENOMEM;
6688         sec->sid = current_sid();
6689
6690         *ib_sec = sec;
6691         return 0;
6692 }
6693
6694 static void selinux_ib_free_security(void *ib_sec)
6695 {
6696         kfree(ib_sec);
6697 }
6698 #endif
6699
6700 #ifdef CONFIG_BPF_SYSCALL
6701 static int selinux_bpf(int cmd, union bpf_attr *attr,
6702                                      unsigned int size)
6703 {
6704         u32 sid = current_sid();
6705         int ret;
6706
6707         switch (cmd) {
6708         case BPF_MAP_CREATE:
6709                 ret = avc_has_perm(&selinux_state,
6710                                    sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6711                                    NULL);
6712                 break;
6713         case BPF_PROG_LOAD:
6714                 ret = avc_has_perm(&selinux_state,
6715                                    sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6716                                    NULL);
6717                 break;
6718         default:
6719                 ret = 0;
6720                 break;
6721         }
6722
6723         return ret;
6724 }
6725
6726 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6727 {
6728         u32 av = 0;
6729
6730         if (fmode & FMODE_READ)
6731                 av |= BPF__MAP_READ;
6732         if (fmode & FMODE_WRITE)
6733                 av |= BPF__MAP_WRITE;
6734         return av;
6735 }
6736
6737 /* This function will check the file pass through unix socket or binder to see
6738  * if it is a bpf related object. And apply correspinding checks on the bpf
6739  * object based on the type. The bpf maps and programs, not like other files and
6740  * socket, are using a shared anonymous inode inside the kernel as their inode.
6741  * So checking that inode cannot identify if the process have privilege to
6742  * access the bpf object and that's why we have to add this additional check in
6743  * selinux_file_receive and selinux_binder_transfer_files.
6744  */
6745 static int bpf_fd_pass(struct file *file, u32 sid)
6746 {
6747         struct bpf_security_struct *bpfsec;
6748         struct bpf_prog *prog;
6749         struct bpf_map *map;
6750         int ret;
6751
6752         if (file->f_op == &bpf_map_fops) {
6753                 map = file->private_data;
6754                 bpfsec = map->security;
6755                 ret = avc_has_perm(&selinux_state,
6756                                    sid, bpfsec->sid, SECCLASS_BPF,
6757                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6758                 if (ret)
6759                         return ret;
6760         } else if (file->f_op == &bpf_prog_fops) {
6761                 prog = file->private_data;
6762                 bpfsec = prog->aux->security;
6763                 ret = avc_has_perm(&selinux_state,
6764                                    sid, bpfsec->sid, SECCLASS_BPF,
6765                                    BPF__PROG_RUN, NULL);
6766                 if (ret)
6767                         return ret;
6768         }
6769         return 0;
6770 }
6771
6772 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6773 {
6774         u32 sid = current_sid();
6775         struct bpf_security_struct *bpfsec;
6776
6777         bpfsec = map->security;
6778         return avc_has_perm(&selinux_state,
6779                             sid, bpfsec->sid, SECCLASS_BPF,
6780                             bpf_map_fmode_to_av(fmode), NULL);
6781 }
6782
6783 static int selinux_bpf_prog(struct bpf_prog *prog)
6784 {
6785         u32 sid = current_sid();
6786         struct bpf_security_struct *bpfsec;
6787
6788         bpfsec = prog->aux->security;
6789         return avc_has_perm(&selinux_state,
6790                             sid, bpfsec->sid, SECCLASS_BPF,
6791                             BPF__PROG_RUN, NULL);
6792 }
6793
6794 static int selinux_bpf_map_alloc(struct bpf_map *map)
6795 {
6796         struct bpf_security_struct *bpfsec;
6797
6798         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6799         if (!bpfsec)
6800                 return -ENOMEM;
6801
6802         bpfsec->sid = current_sid();
6803         map->security = bpfsec;
6804
6805         return 0;
6806 }
6807
6808 static void selinux_bpf_map_free(struct bpf_map *map)
6809 {
6810         struct bpf_security_struct *bpfsec = map->security;
6811
6812         map->security = NULL;
6813         kfree(bpfsec);
6814 }
6815
6816 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6817 {
6818         struct bpf_security_struct *bpfsec;
6819
6820         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6821         if (!bpfsec)
6822                 return -ENOMEM;
6823
6824         bpfsec->sid = current_sid();
6825         aux->security = bpfsec;
6826
6827         return 0;
6828 }
6829
6830 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6831 {
6832         struct bpf_security_struct *bpfsec = aux->security;
6833
6834         aux->security = NULL;
6835         kfree(bpfsec);
6836 }
6837 #endif
6838
6839 static int selinux_lockdown(enum lockdown_reason what)
6840 {
6841         struct common_audit_data ad;
6842         u32 sid = current_sid();
6843         int invalid_reason = (what <= LOCKDOWN_NONE) ||
6844                              (what == LOCKDOWN_INTEGRITY_MAX) ||
6845                              (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
6846
6847         if (WARN(invalid_reason, "Invalid lockdown reason")) {
6848                 audit_log(audit_context(),
6849                           GFP_ATOMIC, AUDIT_SELINUX_ERR,
6850                           "lockdown_reason=invalid");
6851                 return -EINVAL;
6852         }
6853
6854         ad.type = LSM_AUDIT_DATA_LOCKDOWN;
6855         ad.u.reason = what;
6856
6857         if (what <= LOCKDOWN_INTEGRITY_MAX)
6858                 return avc_has_perm(&selinux_state,
6859                                     sid, sid, SECCLASS_LOCKDOWN,
6860                                     LOCKDOWN__INTEGRITY, &ad);
6861         else
6862                 return avc_has_perm(&selinux_state,
6863                                     sid, sid, SECCLASS_LOCKDOWN,
6864                                     LOCKDOWN__CONFIDENTIALITY, &ad);
6865 }
6866
6867 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6868         .lbs_cred = sizeof(struct task_security_struct),
6869         .lbs_file = sizeof(struct file_security_struct),
6870         .lbs_inode = sizeof(struct inode_security_struct),
6871         .lbs_ipc = sizeof(struct ipc_security_struct),
6872         .lbs_msg_msg = sizeof(struct msg_security_struct),
6873 };
6874
6875 #ifdef CONFIG_PERF_EVENTS
6876 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6877 {
6878         u32 requested, sid = current_sid();
6879
6880         if (type == PERF_SECURITY_OPEN)
6881                 requested = PERF_EVENT__OPEN;
6882         else if (type == PERF_SECURITY_CPU)
6883                 requested = PERF_EVENT__CPU;
6884         else if (type == PERF_SECURITY_KERNEL)
6885                 requested = PERF_EVENT__KERNEL;
6886         else if (type == PERF_SECURITY_TRACEPOINT)
6887                 requested = PERF_EVENT__TRACEPOINT;
6888         else
6889                 return -EINVAL;
6890
6891         return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
6892                             requested, NULL);
6893 }
6894
6895 static int selinux_perf_event_alloc(struct perf_event *event)
6896 {
6897         struct perf_event_security_struct *perfsec;
6898
6899         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6900         if (!perfsec)
6901                 return -ENOMEM;
6902
6903         perfsec->sid = current_sid();
6904         event->security = perfsec;
6905
6906         return 0;
6907 }
6908
6909 static void selinux_perf_event_free(struct perf_event *event)
6910 {
6911         struct perf_event_security_struct *perfsec = event->security;
6912
6913         event->security = NULL;
6914         kfree(perfsec);
6915 }
6916
6917 static int selinux_perf_event_read(struct perf_event *event)
6918 {
6919         struct perf_event_security_struct *perfsec = event->security;
6920         u32 sid = current_sid();
6921
6922         return avc_has_perm(&selinux_state, sid, perfsec->sid,
6923                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6924 }
6925
6926 static int selinux_perf_event_write(struct perf_event *event)
6927 {
6928         struct perf_event_security_struct *perfsec = event->security;
6929         u32 sid = current_sid();
6930
6931         return avc_has_perm(&selinux_state, sid, perfsec->sid,
6932                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6933 }
6934 #endif
6935
6936 /*
6937  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6938  * 1. any hooks that don't belong to (2.) or (3.) below,
6939  * 2. hooks that both access structures allocated by other hooks, and allocate
6940  *    structures that can be later accessed by other hooks (mostly "cloning"
6941  *    hooks),
6942  * 3. hooks that only allocate structures that can be later accessed by other
6943  *    hooks ("allocating" hooks).
6944  *
6945  * Please follow block comment delimiters in the list to keep this order.
6946  *
6947  * This ordering is needed for SELinux runtime disable to work at least somewhat
6948  * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6949  * when disabling SELinux at runtime.
6950  */
6951 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6952         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6953         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6954         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6955         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6956
6957         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6958         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6959         LSM_HOOK_INIT(capget, selinux_capget),
6960         LSM_HOOK_INIT(capset, selinux_capset),
6961         LSM_HOOK_INIT(capable, selinux_capable),
6962         LSM_HOOK_INIT(quotactl, selinux_quotactl),
6963         LSM_HOOK_INIT(quota_on, selinux_quota_on),
6964         LSM_HOOK_INIT(syslog, selinux_syslog),
6965         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6966
6967         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6968
6969         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6970         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6971         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6972
6973         LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6974         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6975         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6976         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6977         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6978         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6979         LSM_HOOK_INIT(sb_mount, selinux_mount),
6980         LSM_HOOK_INIT(sb_umount, selinux_umount),
6981         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6982         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6983
6984         LSM_HOOK_INIT(move_mount, selinux_move_mount),
6985
6986         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6987         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6988
6989         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6990         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6991         LSM_HOOK_INIT(inode_create, selinux_inode_create),
6992         LSM_HOOK_INIT(inode_link, selinux_inode_link),
6993         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6994         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6995         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6996         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6997         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6998         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6999         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7000         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7001         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7002         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7003         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7004         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7005         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7006         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7007         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7008         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7009         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7010         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7011         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7012         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7013         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7014         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7015         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7016
7017         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7018
7019         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7020         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7021         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7022         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7023         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7024         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7025         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7026         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7027         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7028         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7029         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7030
7031         LSM_HOOK_INIT(file_open, selinux_file_open),
7032
7033         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7034         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7035         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7036         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7037         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7038         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7039         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7040         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7041         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7042         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7043         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7044         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7045         LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
7046         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7047         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7048         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7049         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7050         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7051         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7052         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7053         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7054         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7055         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7056
7057         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7058         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7059
7060         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7061         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7062         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7063         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7064
7065         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7066         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7067         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7068
7069         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7070         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7071         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7072
7073         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7074
7075         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7076         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7077
7078         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7079         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7080         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7081         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7082         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7083         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7084
7085         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7086         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7087
7088         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7089         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7090         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7091         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7092         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7093         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7094         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7095         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7096         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7097         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7098         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7099         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7100         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7101         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7102         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7103         LSM_HOOK_INIT(socket_getpeersec_stream,
7104                         selinux_socket_getpeersec_stream),
7105         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7106         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7107         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7108         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7109         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7110         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7111         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7112         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7113         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7114         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7115         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7116         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7117         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7118         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7119         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7120         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7121         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7122         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7123         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7124         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7125 #ifdef CONFIG_SECURITY_INFINIBAND
7126         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7127         LSM_HOOK_INIT(ib_endport_manage_subnet,
7128                       selinux_ib_endport_manage_subnet),
7129         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7130 #endif
7131 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7132         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7133         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7134         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7135         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7136         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7137         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7138                         selinux_xfrm_state_pol_flow_match),
7139         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7140 #endif
7141
7142 #ifdef CONFIG_KEYS
7143         LSM_HOOK_INIT(key_free, selinux_key_free),
7144         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7145         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7146 #ifdef CONFIG_KEY_NOTIFICATIONS
7147         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7148 #endif
7149 #endif
7150
7151 #ifdef CONFIG_AUDIT
7152         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7153         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7154         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7155 #endif
7156
7157 #ifdef CONFIG_BPF_SYSCALL
7158         LSM_HOOK_INIT(bpf, selinux_bpf),
7159         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7160         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7161         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7162         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7163 #endif
7164
7165 #ifdef CONFIG_PERF_EVENTS
7166         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7167         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7168         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7169         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7170 #endif
7171
7172         LSM_HOOK_INIT(locked_down, selinux_lockdown),
7173
7174         /*
7175          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7176          */
7177         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7178         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7179         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7180         LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7181 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7182         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7183 #endif
7184
7185         /*
7186          * PUT "ALLOCATING" HOOKS HERE
7187          */
7188         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7189         LSM_HOOK_INIT(msg_queue_alloc_security,
7190                       selinux_msg_queue_alloc_security),
7191         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7192         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7193         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7194         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7195         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7196         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7197         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7198         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7199 #ifdef CONFIG_SECURITY_INFINIBAND
7200         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7201 #endif
7202 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7203         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7204         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7205         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7206                       selinux_xfrm_state_alloc_acquire),
7207 #endif
7208 #ifdef CONFIG_KEYS
7209         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7210 #endif
7211 #ifdef CONFIG_AUDIT
7212         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7213 #endif
7214 #ifdef CONFIG_BPF_SYSCALL
7215         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7216         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7217 #endif
7218 #ifdef CONFIG_PERF_EVENTS
7219         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7220 #endif
7221 };
7222
7223 static __init int selinux_init(void)
7224 {
7225         pr_info("SELinux:  Initializing.\n");
7226
7227         memset(&selinux_state, 0, sizeof(selinux_state));
7228         enforcing_set(&selinux_state, selinux_enforcing_boot);
7229         selinux_state.checkreqprot = selinux_checkreqprot_boot;
7230         selinux_ss_init(&selinux_state.ss);
7231         selinux_avc_init(&selinux_state.avc);
7232         mutex_init(&selinux_state.status_lock);
7233
7234         /* Set the security state for the initial task. */
7235         cred_init_security();
7236
7237         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7238
7239         avc_init();
7240
7241         avtab_cache_init();
7242
7243         ebitmap_cache_init();
7244
7245         hashtab_cache_init();
7246
7247         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7248
7249         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7250                 panic("SELinux: Unable to register AVC netcache callback\n");
7251
7252         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7253                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7254
7255         if (selinux_enforcing_boot)
7256                 pr_debug("SELinux:  Starting in enforcing mode\n");
7257         else
7258                 pr_debug("SELinux:  Starting in permissive mode\n");
7259
7260         fs_validate_description("selinux", selinux_fs_parameters);
7261
7262         return 0;
7263 }
7264
7265 static void delayed_superblock_init(struct super_block *sb, void *unused)
7266 {
7267         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7268 }
7269
7270 void selinux_complete_init(void)
7271 {
7272         pr_debug("SELinux:  Completing initialization.\n");
7273
7274         /* Set up any superblocks initialized prior to the policy load. */
7275         pr_debug("SELinux:  Setting up existing superblocks.\n");
7276         iterate_supers(delayed_superblock_init, NULL);
7277 }
7278
7279 /* SELinux requires early initialization in order to label
7280    all processes and objects when they are created. */
7281 DEFINE_LSM(selinux) = {
7282         .name = "selinux",
7283         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7284         .enabled = &selinux_enabled_boot,
7285         .blobs = &selinux_blob_sizes,
7286         .init = selinux_init,
7287 };
7288
7289 #if defined(CONFIG_NETFILTER)
7290
7291 static const struct nf_hook_ops selinux_nf_ops[] = {
7292         {
7293                 .hook =         selinux_ipv4_postroute,
7294                 .pf =           NFPROTO_IPV4,
7295                 .hooknum =      NF_INET_POST_ROUTING,
7296                 .priority =     NF_IP_PRI_SELINUX_LAST,
7297         },
7298         {
7299                 .hook =         selinux_ipv4_forward,
7300                 .pf =           NFPROTO_IPV4,
7301                 .hooknum =      NF_INET_FORWARD,
7302                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7303         },
7304         {
7305                 .hook =         selinux_ipv4_output,
7306                 .pf =           NFPROTO_IPV4,
7307                 .hooknum =      NF_INET_LOCAL_OUT,
7308                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7309         },
7310 #if IS_ENABLED(CONFIG_IPV6)
7311         {
7312                 .hook =         selinux_ipv6_postroute,
7313                 .pf =           NFPROTO_IPV6,
7314                 .hooknum =      NF_INET_POST_ROUTING,
7315                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7316         },
7317         {
7318                 .hook =         selinux_ipv6_forward,
7319                 .pf =           NFPROTO_IPV6,
7320                 .hooknum =      NF_INET_FORWARD,
7321                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7322         },
7323         {
7324                 .hook =         selinux_ipv6_output,
7325                 .pf =           NFPROTO_IPV6,
7326                 .hooknum =      NF_INET_LOCAL_OUT,
7327                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7328         },
7329 #endif  /* IPV6 */
7330 };
7331
7332 static int __net_init selinux_nf_register(struct net *net)
7333 {
7334         return nf_register_net_hooks(net, selinux_nf_ops,
7335                                      ARRAY_SIZE(selinux_nf_ops));
7336 }
7337
7338 static void __net_exit selinux_nf_unregister(struct net *net)
7339 {
7340         nf_unregister_net_hooks(net, selinux_nf_ops,
7341                                 ARRAY_SIZE(selinux_nf_ops));
7342 }
7343
7344 static struct pernet_operations selinux_net_ops = {
7345         .init = selinux_nf_register,
7346         .exit = selinux_nf_unregister,
7347 };
7348
7349 static int __init selinux_nf_ip_init(void)
7350 {
7351         int err;
7352
7353         if (!selinux_enabled_boot)
7354                 return 0;
7355
7356         pr_debug("SELinux:  Registering netfilter hooks\n");
7357
7358         err = register_pernet_subsys(&selinux_net_ops);
7359         if (err)
7360                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7361
7362         return 0;
7363 }
7364 __initcall(selinux_nf_ip_init);
7365
7366 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7367 static void selinux_nf_ip_exit(void)
7368 {
7369         pr_debug("SELinux:  Unregistering netfilter hooks\n");
7370
7371         unregister_pernet_subsys(&selinux_net_ops);
7372 }
7373 #endif
7374
7375 #else /* CONFIG_NETFILTER */
7376
7377 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7378 #define selinux_nf_ip_exit()
7379 #endif
7380
7381 #endif /* CONFIG_NETFILTER */
7382
7383 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7384 int selinux_disable(struct selinux_state *state)
7385 {
7386         if (selinux_initialized(state)) {
7387                 /* Not permitted after initial policy load. */
7388                 return -EINVAL;
7389         }
7390
7391         if (selinux_disabled(state)) {
7392                 /* Only do this once. */
7393                 return -EINVAL;
7394         }
7395
7396         selinux_mark_disabled(state);
7397
7398         pr_info("SELinux:  Disabled at runtime.\n");
7399
7400         /*
7401          * Unregister netfilter hooks.
7402          * Must be done before security_delete_hooks() to avoid breaking
7403          * runtime disable.
7404          */
7405         selinux_nf_ip_exit();
7406
7407         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7408
7409         /* Try to destroy the avc node cache */
7410         avc_disable();
7411
7412         /* Unregister selinuxfs. */
7413         exit_sel_fs();
7414
7415         return 0;
7416 }
7417 #endif