1 /* Common capabilities, needed by capability.o.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
10 #include <linux/capability.h>
11 #include <linux/audit.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/security.h>
16 #include <linux/file.h>
18 #include <linux/mman.h>
19 #include <linux/pagemap.h>
20 #include <linux/swap.h>
21 #include <linux/skbuff.h>
22 #include <linux/netlink.h>
23 #include <linux/ptrace.h>
24 #include <linux/xattr.h>
25 #include <linux/hugetlb.h>
26 #include <linux/mount.h>
27 #include <linux/sched.h>
28 #include <linux/prctl.h>
29 #include <linux/securebits.h>
30 #include <linux/user_namespace.h>
33 * If a non-root user executes a setuid-root binary in
34 * !secure(SECURE_NOROOT) mode, then we raise capabilities.
35 * However if fE is also set, then the intent is for only
36 * the file capabilities to be applied, and the setuid-root
37 * bit is left on either to change the uid (plausible) or
38 * to get full privilege on a kernel without file capabilities
39 * support. So in that case we do not raise capabilities.
41 * Warn if that happens, once per boot.
43 static void warn_setuid_and_fcaps_mixed(const char *fname)
47 printk(KERN_INFO "warning: `%s' has both setuid-root and"
48 " effective capabilities. Therefore not raising all"
49 " capabilities.\n", fname);
54 int cap_netlink_send(struct sock *sk, struct sk_buff *skb)
60 * cap_capable - Determine whether a task has a particular effective capability
61 * @cred: The credentials to use
62 * @ns: The user namespace in which we need the capability
63 * @cap: The capability to check for
64 * @audit: Whether to write an audit message or not
66 * Determine whether the nominated task has the specified capability amongst
67 * its effective set, returning 0 if it does, -ve if it does not.
69 * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable()
70 * and has_capability() functions. That is, it has the reverse semantics:
71 * cap_has_capability() returns 0 when a task has a capability, but the
72 * kernel's capable() and has_capability() returns 1 for this case.
74 int cap_capable(const struct cred *cred, struct user_namespace *targ_ns,
78 /* The creator of the user namespace has all caps. */
79 if (targ_ns != &init_user_ns && targ_ns->creator == cred->user)
82 /* Do we have the necessary capabilities? */
83 if (targ_ns == cred->user->user_ns)
84 return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
86 /* Have we tried all of the parent namespaces? */
87 if (targ_ns == &init_user_ns)
91 *If you have a capability in a parent user ns, then you have
92 * it over all children user namespaces as well.
94 targ_ns = targ_ns->creator->user_ns;
97 /* We never get here */
101 * cap_settime - Determine whether the current process may set the system clock
102 * @ts: The time to set
103 * @tz: The timezone to set
105 * Determine whether the current process may set the system clock and timezone
106 * information, returning 0 if permission granted, -ve if denied.
108 int cap_settime(const struct timespec *ts, const struct timezone *tz)
110 if (!capable(CAP_SYS_TIME))
116 * cap_ptrace_access_check - Determine whether the current process may access
118 * @child: The process to be accessed
119 * @mode: The mode of attachment.
121 * If we are in the same or an ancestor user_ns and have all the target
122 * task's capabilities, then ptrace access is allowed.
123 * If we have the ptrace capability to the target user_ns, then ptrace
127 * Determine whether a process may access another, returning 0 if permission
128 * granted, -ve if denied.
130 int cap_ptrace_access_check(struct task_struct *child, unsigned int mode)
133 const struct cred *cred, *child_cred;
136 cred = current_cred();
137 child_cred = __task_cred(child);
138 if (cred->user->user_ns == child_cred->user->user_ns &&
139 cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
141 if (ns_capable(child_cred->user->user_ns, CAP_SYS_PTRACE))
150 * cap_ptrace_traceme - Determine whether another process may trace the current
151 * @parent: The task proposed to be the tracer
153 * If parent is in the same or an ancestor user_ns and has all current's
154 * capabilities, then ptrace access is allowed.
155 * If parent has the ptrace capability to current's user_ns, then ptrace
159 * Determine whether the nominated task is permitted to trace the current
160 * process, returning 0 if permission is granted, -ve if denied.
162 int cap_ptrace_traceme(struct task_struct *parent)
165 const struct cred *cred, *child_cred;
168 cred = __task_cred(parent);
169 child_cred = current_cred();
170 if (cred->user->user_ns == child_cred->user->user_ns &&
171 cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
173 if (has_ns_capability(parent, child_cred->user->user_ns, CAP_SYS_PTRACE))
182 * cap_capget - Retrieve a task's capability sets
183 * @target: The task from which to retrieve the capability sets
184 * @effective: The place to record the effective set
185 * @inheritable: The place to record the inheritable set
186 * @permitted: The place to record the permitted set
188 * This function retrieves the capabilities of the nominated task and returns
189 * them to the caller.
191 int cap_capget(struct task_struct *target, kernel_cap_t *effective,
192 kernel_cap_t *inheritable, kernel_cap_t *permitted)
194 const struct cred *cred;
196 /* Derived from kernel/capability.c:sys_capget. */
198 cred = __task_cred(target);
199 *effective = cred->cap_effective;
200 *inheritable = cred->cap_inheritable;
201 *permitted = cred->cap_permitted;
207 * Determine whether the inheritable capabilities are limited to the old
208 * permitted set. Returns 1 if they are limited, 0 if they are not.
210 static inline int cap_inh_is_capped(void)
213 /* they are so limited unless the current task has the CAP_SETPCAP
216 if (cap_capable(current_cred(), current_cred()->user->user_ns,
217 CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0)
223 * cap_capset - Validate and apply proposed changes to current's capabilities
224 * @new: The proposed new credentials; alterations should be made here
225 * @old: The current task's current credentials
226 * @effective: A pointer to the proposed new effective capabilities set
227 * @inheritable: A pointer to the proposed new inheritable capabilities set
228 * @permitted: A pointer to the proposed new permitted capabilities set
230 * This function validates and applies a proposed mass change to the current
231 * process's capability sets. The changes are made to the proposed new
232 * credentials, and assuming no error, will be committed by the caller of LSM.
234 int cap_capset(struct cred *new,
235 const struct cred *old,
236 const kernel_cap_t *effective,
237 const kernel_cap_t *inheritable,
238 const kernel_cap_t *permitted)
240 if (cap_inh_is_capped() &&
241 !cap_issubset(*inheritable,
242 cap_combine(old->cap_inheritable,
243 old->cap_permitted)))
244 /* incapable of using this inheritable set */
247 if (!cap_issubset(*inheritable,
248 cap_combine(old->cap_inheritable,
250 /* no new pI capabilities outside bounding set */
253 /* verify restrictions on target's new Permitted set */
254 if (!cap_issubset(*permitted, old->cap_permitted))
257 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
258 if (!cap_issubset(*effective, *permitted))
261 new->cap_effective = *effective;
262 new->cap_inheritable = *inheritable;
263 new->cap_permitted = *permitted;
268 * Clear proposed capability sets for execve().
270 static inline void bprm_clear_caps(struct linux_binprm *bprm)
272 cap_clear(bprm->cred->cap_permitted);
273 bprm->cap_effective = false;
277 * cap_inode_need_killpriv - Determine if inode change affects privileges
278 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV
280 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
281 * affects the security markings on that inode, and if it is, should
282 * inode_killpriv() be invoked or the change rejected?
284 * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and
285 * -ve to deny the change.
287 int cap_inode_need_killpriv(struct dentry *dentry)
289 struct inode *inode = dentry->d_inode;
292 if (!inode->i_op->getxattr)
295 error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
302 * cap_inode_killpriv - Erase the security markings on an inode
303 * @dentry: The inode/dentry to alter
305 * Erase the privilege-enhancing security markings on an inode.
307 * Returns 0 if successful, -ve on error.
309 int cap_inode_killpriv(struct dentry *dentry)
311 struct inode *inode = dentry->d_inode;
313 if (!inode->i_op->removexattr)
316 return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
320 * Calculate the new process capability sets from the capability sets attached
323 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
324 struct linux_binprm *bprm,
328 struct cred *new = bprm->cred;
332 if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE)
335 if (caps->magic_etc & VFS_CAP_REVISION_MASK)
338 CAP_FOR_EACH_U32(i) {
339 __u32 permitted = caps->permitted.cap[i];
340 __u32 inheritable = caps->inheritable.cap[i];
343 * pP' = (X & fP) | (pI & fI)
345 new->cap_permitted.cap[i] =
346 (new->cap_bset.cap[i] & permitted) |
347 (new->cap_inheritable.cap[i] & inheritable);
349 if (permitted & ~new->cap_permitted.cap[i])
350 /* insufficient to execute correctly */
355 * For legacy apps, with no internal support for recognizing they
356 * do not have enough capabilities, we return an error if they are
357 * missing some "forced" (aka file-permitted) capabilities.
359 return *effective ? ret : 0;
363 * Extract the on-exec-apply capability sets for an executable file.
365 int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps)
367 struct inode *inode = dentry->d_inode;
371 struct vfs_cap_data caps;
373 memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
375 if (!inode || !inode->i_op->getxattr)
378 size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps,
380 if (size == -ENODATA || size == -EOPNOTSUPP)
381 /* no data, that's ok */
386 if (size < sizeof(magic_etc))
389 cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps.magic_etc);
391 switch (magic_etc & VFS_CAP_REVISION_MASK) {
392 case VFS_CAP_REVISION_1:
393 if (size != XATTR_CAPS_SZ_1)
395 tocopy = VFS_CAP_U32_1;
397 case VFS_CAP_REVISION_2:
398 if (size != XATTR_CAPS_SZ_2)
400 tocopy = VFS_CAP_U32_2;
406 CAP_FOR_EACH_U32(i) {
409 cpu_caps->permitted.cap[i] = le32_to_cpu(caps.data[i].permitted);
410 cpu_caps->inheritable.cap[i] = le32_to_cpu(caps.data[i].inheritable);
417 * Attempt to get the on-exec apply capability sets for an executable file from
418 * its xattrs and, if present, apply them to the proposed credentials being
419 * constructed by execve().
421 static int get_file_caps(struct linux_binprm *bprm, bool *effective, bool *has_cap)
423 struct dentry *dentry;
425 struct cpu_vfs_cap_data vcaps;
427 bprm_clear_caps(bprm);
429 if (!file_caps_enabled)
432 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
435 dentry = dget(bprm->file->f_dentry);
437 rc = get_vfs_caps_from_disk(dentry, &vcaps);
440 printk(KERN_NOTICE "%s: get_vfs_caps_from_disk returned %d for %s\n",
441 __func__, rc, bprm->filename);
442 else if (rc == -ENODATA)
447 rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective, has_cap);
449 printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",
450 __func__, rc, bprm->filename);
455 bprm_clear_caps(bprm);
461 * cap_bprm_set_creds - Set up the proposed credentials for execve().
462 * @bprm: The execution parameters, including the proposed creds
464 * Set up the proposed credentials for a new execution context being
465 * constructed by execve(). The proposed creds in @bprm->cred is altered,
466 * which won't take effect immediately. Returns 0 if successful, -ve on error.
468 int cap_bprm_set_creds(struct linux_binprm *bprm)
470 const struct cred *old = current_cred();
471 struct cred *new = bprm->cred;
472 bool effective, has_cap = false;
476 ret = get_file_caps(bprm, &effective, &has_cap);
480 if (!issecure(SECURE_NOROOT)) {
482 * If the legacy file capability is set, then don't set privs
483 * for a setuid root binary run by a non-root user. Do set it
484 * for a root user just to cause least surprise to an admin.
486 if (has_cap && new->uid != 0 && new->euid == 0) {
487 warn_setuid_and_fcaps_mixed(bprm->filename);
491 * To support inheritance of root-permissions and suid-root
492 * executables under compatibility mode, we override the
493 * capability sets for the file.
495 * If only the real uid is 0, we do not set the effective bit.
497 if (new->euid == 0 || new->uid == 0) {
498 /* pP' = (cap_bset & ~0) | (pI & ~0) */
499 new->cap_permitted = cap_combine(old->cap_bset,
500 old->cap_inheritable);
507 /* Don't let someone trace a set[ug]id/setpcap binary with the revised
508 * credentials unless they have the appropriate permit
510 if ((new->euid != old->uid ||
511 new->egid != old->gid ||
512 !cap_issubset(new->cap_permitted, old->cap_permitted)) &&
513 bprm->unsafe & ~LSM_UNSAFE_PTRACE_CAP) {
514 /* downgrade; they get no more than they had, and maybe less */
515 if (!capable(CAP_SETUID)) {
516 new->euid = new->uid;
517 new->egid = new->gid;
519 new->cap_permitted = cap_intersect(new->cap_permitted,
523 new->suid = new->fsuid = new->euid;
524 new->sgid = new->fsgid = new->egid;
527 new->cap_effective = new->cap_permitted;
529 cap_clear(new->cap_effective);
530 bprm->cap_effective = effective;
533 * Audit candidate if current->cap_effective is set
535 * We do not bother to audit if 3 things are true:
536 * 1) cap_effective has all caps
538 * 3) root is supposed to have all caps (SECURE_NOROOT)
539 * Since this is just a normal root execing a process.
541 * Number 1 above might fail if you don't have a full bset, but I think
542 * that is interesting information to audit.
544 if (!cap_isclear(new->cap_effective)) {
545 if (!cap_issubset(CAP_FULL_SET, new->cap_effective) ||
546 new->euid != 0 || new->uid != 0 ||
547 issecure(SECURE_NOROOT)) {
548 ret = audit_log_bprm_fcaps(bprm, new, old);
554 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
559 * cap_bprm_secureexec - Determine whether a secure execution is required
560 * @bprm: The execution parameters
562 * Determine whether a secure execution is required, return 1 if it is, and 0
565 * The credentials have been committed by this point, and so are no longer
566 * available through @bprm->cred.
568 int cap_bprm_secureexec(struct linux_binprm *bprm)
570 const struct cred *cred = current_cred();
572 if (cred->uid != 0) {
573 if (bprm->cap_effective)
575 if (!cap_isclear(cred->cap_permitted))
579 return (cred->euid != cred->uid ||
580 cred->egid != cred->gid);
584 * cap_inode_setxattr - Determine whether an xattr may be altered
585 * @dentry: The inode/dentry being altered
586 * @name: The name of the xattr to be changed
587 * @value: The value that the xattr will be changed to
588 * @size: The size of value
589 * @flags: The replacement flag
591 * Determine whether an xattr may be altered or set on an inode, returning 0 if
592 * permission is granted, -ve if denied.
594 * This is used to make sure security xattrs don't get updated or set by those
595 * who aren't privileged to do so.
597 int cap_inode_setxattr(struct dentry *dentry, const char *name,
598 const void *value, size_t size, int flags)
600 if (!strcmp(name, XATTR_NAME_CAPS)) {
601 if (!capable(CAP_SETFCAP))
606 if (!strncmp(name, XATTR_SECURITY_PREFIX,
607 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
608 !capable(CAP_SYS_ADMIN))
614 * cap_inode_removexattr - Determine whether an xattr may be removed
615 * @dentry: The inode/dentry being altered
616 * @name: The name of the xattr to be changed
618 * Determine whether an xattr may be removed from an inode, returning 0 if
619 * permission is granted, -ve if denied.
621 * This is used to make sure security xattrs don't get removed by those who
622 * aren't privileged to remove them.
624 int cap_inode_removexattr(struct dentry *dentry, const char *name)
626 if (!strcmp(name, XATTR_NAME_CAPS)) {
627 if (!capable(CAP_SETFCAP))
632 if (!strncmp(name, XATTR_SECURITY_PREFIX,
633 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
634 !capable(CAP_SYS_ADMIN))
640 * cap_emulate_setxuid() fixes the effective / permitted capabilities of
641 * a process after a call to setuid, setreuid, or setresuid.
643 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
644 * {r,e,s}uid != 0, the permitted and effective capabilities are
647 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
648 * capabilities of the process are cleared.
650 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
651 * capabilities are set to the permitted capabilities.
653 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
658 * cevans - New behaviour, Oct '99
659 * A process may, via prctl(), elect to keep its capabilities when it
660 * calls setuid() and switches away from uid==0. Both permitted and
661 * effective sets will be retained.
662 * Without this change, it was impossible for a daemon to drop only some
663 * of its privilege. The call to setuid(!=0) would drop all privileges!
664 * Keeping uid 0 is not an option because uid 0 owns too many vital
666 * Thanks to Olaf Kirch and Peter Benie for spotting this.
668 static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old)
670 if ((old->uid == 0 || old->euid == 0 || old->suid == 0) &&
671 (new->uid != 0 && new->euid != 0 && new->suid != 0) &&
672 !issecure(SECURE_KEEP_CAPS)) {
673 cap_clear(new->cap_permitted);
674 cap_clear(new->cap_effective);
676 if (old->euid == 0 && new->euid != 0)
677 cap_clear(new->cap_effective);
678 if (old->euid != 0 && new->euid == 0)
679 new->cap_effective = new->cap_permitted;
683 * cap_task_fix_setuid - Fix up the results of setuid() call
684 * @new: The proposed credentials
685 * @old: The current task's current credentials
686 * @flags: Indications of what has changed
688 * Fix up the results of setuid() call before the credential changes are
689 * actually applied, returning 0 to grant the changes, -ve to deny them.
691 int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags)
697 /* juggle the capabilities to follow [RES]UID changes unless
698 * otherwise suppressed */
699 if (!issecure(SECURE_NO_SETUID_FIXUP))
700 cap_emulate_setxuid(new, old);
704 /* juggle the capabilties to follow FSUID changes, unless
705 * otherwise suppressed
707 * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
708 * if not, we might be a bit too harsh here.
710 if (!issecure(SECURE_NO_SETUID_FIXUP)) {
711 if (old->fsuid == 0 && new->fsuid != 0)
713 cap_drop_fs_set(new->cap_effective);
715 if (old->fsuid != 0 && new->fsuid == 0)
717 cap_raise_fs_set(new->cap_effective,
730 * Rationale: code calling task_setscheduler, task_setioprio, and
731 * task_setnice, assumes that
732 * . if capable(cap_sys_nice), then those actions should be allowed
733 * . if not capable(cap_sys_nice), but acting on your own processes,
734 * then those actions should be allowed
735 * This is insufficient now since you can call code without suid, but
736 * yet with increased caps.
737 * So we check for increased caps on the target process.
739 static int cap_safe_nice(struct task_struct *p)
744 is_subset = cap_issubset(__task_cred(p)->cap_permitted,
745 current_cred()->cap_permitted);
748 if (!is_subset && !capable(CAP_SYS_NICE))
754 * cap_task_setscheduler - Detemine if scheduler policy change is permitted
755 * @p: The task to affect
757 * Detemine if the requested scheduler policy change is permitted for the
758 * specified task, returning 0 if permission is granted, -ve if denied.
760 int cap_task_setscheduler(struct task_struct *p)
762 return cap_safe_nice(p);
766 * cap_task_ioprio - Detemine if I/O priority change is permitted
767 * @p: The task to affect
768 * @ioprio: The I/O priority to set
770 * Detemine if the requested I/O priority change is permitted for the specified
771 * task, returning 0 if permission is granted, -ve if denied.
773 int cap_task_setioprio(struct task_struct *p, int ioprio)
775 return cap_safe_nice(p);
779 * cap_task_ioprio - Detemine if task priority change is permitted
780 * @p: The task to affect
781 * @nice: The nice value to set
783 * Detemine if the requested task priority change is permitted for the
784 * specified task, returning 0 if permission is granted, -ve if denied.
786 int cap_task_setnice(struct task_struct *p, int nice)
788 return cap_safe_nice(p);
792 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from
793 * the current task's bounding set. Returns 0 on success, -ve on error.
795 static long cap_prctl_drop(struct cred *new, unsigned long cap)
797 if (!capable(CAP_SETPCAP))
802 cap_lower(new->cap_bset, cap);
807 * cap_task_prctl - Implement process control functions for this security module
808 * @option: The process control function requested
809 * @arg2, @arg3, @arg4, @arg5: The argument data for this function
811 * Allow process control functions (sys_prctl()) to alter capabilities; may
812 * also deny access to other functions not otherwise implemented here.
814 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented
815 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM
816 * modules will consider performing the function.
818 int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
819 unsigned long arg4, unsigned long arg5)
824 new = prepare_creds();
829 case PR_CAPBSET_READ:
831 if (!cap_valid(arg2))
833 error = !!cap_raised(new->cap_bset, arg2);
836 case PR_CAPBSET_DROP:
837 error = cap_prctl_drop(new, arg2);
843 * The next four prctl's remain to assist with transitioning a
844 * system from legacy UID=0 based privilege (when filesystem
845 * capabilities are not in use) to a system using filesystem
846 * capabilities only - as the POSIX.1e draft intended.
850 * PR_SET_SECUREBITS =
851 * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
852 * | issecure_mask(SECURE_NOROOT)
853 * | issecure_mask(SECURE_NOROOT_LOCKED)
854 * | issecure_mask(SECURE_NO_SETUID_FIXUP)
855 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
857 * will ensure that the current process and all of its
858 * children will be locked into a pure
859 * capability-based-privilege environment.
861 case PR_SET_SECUREBITS:
863 if ((((new->securebits & SECURE_ALL_LOCKS) >> 1)
864 & (new->securebits ^ arg2)) /*[1]*/
865 || ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
866 || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
867 || (cap_capable(current_cred(),
868 current_cred()->user->user_ns, CAP_SETPCAP,
869 SECURITY_CAP_AUDIT) != 0) /*[4]*/
871 * [1] no changing of bits that are locked
872 * [2] no unlocking of locks
873 * [3] no setting of unsupported bits
874 * [4] doing anything requires privilege (go read about
875 * the "sendmail capabilities bug")
878 /* cannot change a locked bit */
880 new->securebits = arg2;
883 case PR_GET_SECUREBITS:
884 error = new->securebits;
887 case PR_GET_KEEPCAPS:
888 if (issecure(SECURE_KEEP_CAPS))
892 case PR_SET_KEEPCAPS:
894 if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */
897 if (issecure(SECURE_KEEP_CAPS_LOCKED))
900 new->securebits |= issecure_mask(SECURE_KEEP_CAPS);
902 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
906 /* No functionality available - continue with default */
911 /* Functionality provided */
913 return commit_creds(new);
922 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
923 * @mm: The VM space in which the new mapping is to be made
924 * @pages: The size of the mapping
926 * Determine whether the allocation of a new virtual mapping by the current
927 * task is permitted, returning 0 if permission is granted, -ve if not.
929 int cap_vm_enough_memory(struct mm_struct *mm, long pages)
931 int cap_sys_admin = 0;
933 if (cap_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
934 SECURITY_CAP_NOAUDIT) == 0)
936 return __vm_enough_memory(mm, pages, cap_sys_admin);
940 * cap_file_mmap - check if able to map given addr
945 * @addr: address attempting to be mapped
948 * If the process is attempting to map memory below dac_mmap_min_addr they need
949 * CAP_SYS_RAWIO. The other parameters to this function are unused by the
950 * capability security module. Returns 0 if this mapping should be allowed
953 int cap_file_mmap(struct file *file, unsigned long reqprot,
954 unsigned long prot, unsigned long flags,
955 unsigned long addr, unsigned long addr_only)
959 if (addr < dac_mmap_min_addr) {
960 ret = cap_capable(current_cred(), &init_user_ns, CAP_SYS_RAWIO,
962 /* set PF_SUPERPRIV if it turns out we allow the low mmap */
964 current->flags |= PF_SUPERPRIV;