1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * Generic socket support routines. Memory allocators, socket lock/release
8 * handler for protocols to use and generic option handler.
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
16 * Alan Cox : Numerous verify_area() problems
17 * Alan Cox : Connecting on a connecting socket
18 * now returns an error for tcp.
19 * Alan Cox : sock->protocol is set correctly.
20 * and is not sometimes left as 0.
21 * Alan Cox : connect handles icmp errors on a
22 * connect properly. Unfortunately there
23 * is a restart syscall nasty there. I
24 * can't match BSD without hacking the C
25 * library. Ideas urgently sought!
26 * Alan Cox : Disallow bind() to addresses that are
27 * not ours - especially broadcast ones!!
28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
30 * instead they leave that for the DESTROY timer.
31 * Alan Cox : Clean up error flag in accept
32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer
33 * was buggy. Put a remove_sock() in the handler
34 * for memory when we hit 0. Also altered the timer
35 * code. The ACK stuff can wait and needs major
37 * Alan Cox : Fixed TCP ack bug, removed remove sock
38 * and fixed timer/inet_bh race.
39 * Alan Cox : Added zapped flag for TCP
40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 * Rick Sladkey : Relaxed UDP rules for matching packets.
46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
47 * Pauline Middelink : identd support
48 * Alan Cox : Fixed connect() taking signals I think.
49 * Alan Cox : SO_LINGER supported
50 * Alan Cox : Error reporting fixes
51 * Anonymous : inet_create tidied up (sk->reuse setting)
52 * Alan Cox : inet sockets don't set sk->type!
53 * Alan Cox : Split socket option code
54 * Alan Cox : Callbacks
55 * Alan Cox : Nagle flag for Charles & Johannes stuff
56 * Alex : Removed restriction on inet fioctl
57 * Alan Cox : Splitting INET from NET core
58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
60 * Alan Cox : Split IP from generic code
61 * Alan Cox : New kfree_skbmem()
62 * Alan Cox : Make SO_DEBUG superuser only.
63 * Alan Cox : Allow anyone to clear SO_DEBUG
65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
66 * Alan Cox : Allocator for a socket is settable.
67 * Alan Cox : SO_ERROR includes soft errors.
68 * Alan Cox : Allow NULL arguments on some SO_ opts
69 * Alan Cox : Generic socket allocation to make hooks
70 * easier (suggested by Craig Metz).
71 * Michael Pall : SO_ERROR returns positive errno again
72 * Steve Whitehouse: Added default destructor to free
73 * protocol private data.
74 * Steve Whitehouse: Added various other default routines
75 * common to several socket families.
76 * Chris Evans : Call suser() check last on F_SETOWN
77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
79 * Andi Kleen : Fix write_space callback
80 * Chris Evans : Security fixes - signedness again
81 * Arnaldo C. Melo : cleanups, use skb_queue_purge
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
88 #include <asm/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/init.h>
111 #include <linux/highmem.h>
112 #include <linux/user_namespace.h>
113 #include <linux/static_key.h>
114 #include <linux/memcontrol.h>
115 #include <linux/prefetch.h>
116 #include <linux/compat.h>
118 #include <linux/uaccess.h>
120 #include <linux/netdevice.h>
121 #include <net/protocol.h>
122 #include <linux/skbuff.h>
123 #include <net/net_namespace.h>
124 #include <net/request_sock.h>
125 #include <net/sock.h>
126 #include <linux/net_tstamp.h>
127 #include <net/xfrm.h>
128 #include <linux/ipsec.h>
129 #include <net/cls_cgroup.h>
130 #include <net/netprio_cgroup.h>
131 #include <linux/sock_diag.h>
133 #include <linux/filter.h>
134 #include <net/sock_reuseport.h>
135 #include <net/bpf_sk_storage.h>
137 #include <trace/events/sock.h>
140 #include <net/busy_poll.h>
142 #include <linux/ethtool.h>
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
149 static void sock_def_write_space_wfree(struct sock *sk);
150 static void sock_def_write_space(struct sock *sk);
153 * sk_ns_capable - General socket capability test
154 * @sk: Socket to use a capability on or through
155 * @user_ns: The user namespace of the capability to use
156 * @cap: The capability to use
158 * Test to see if the opener of the socket had when the socket was
159 * created and the current process has the capability @cap in the user
160 * namespace @user_ns.
162 bool sk_ns_capable(const struct sock *sk,
163 struct user_namespace *user_ns, int cap)
165 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
166 ns_capable(user_ns, cap);
168 EXPORT_SYMBOL(sk_ns_capable);
171 * sk_capable - Socket global capability test
172 * @sk: Socket to use a capability on or through
173 * @cap: The global capability to use
175 * Test to see if the opener of the socket had when the socket was
176 * created and the current process has the capability @cap in all user
179 bool sk_capable(const struct sock *sk, int cap)
181 return sk_ns_capable(sk, &init_user_ns, cap);
183 EXPORT_SYMBOL(sk_capable);
186 * sk_net_capable - Network namespace socket capability test
187 * @sk: Socket to use a capability on or through
188 * @cap: The capability to use
190 * Test to see if the opener of the socket had when the socket was created
191 * and the current process has the capability @cap over the network namespace
192 * the socket is a member of.
194 bool sk_net_capable(const struct sock *sk, int cap)
196 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
198 EXPORT_SYMBOL(sk_net_capable);
201 * Each address family might have different locking rules, so we have
202 * one slock key per address family and separate keys for internal and
205 static struct lock_class_key af_family_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_keys[AF_MAX];
207 static struct lock_class_key af_family_slock_keys[AF_MAX];
208 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
211 * Make lock validator output more readable. (we pre-construct these
212 * strings build-time, so that runtime initialization of socket
216 #define _sock_locks(x) \
217 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
218 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
219 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
220 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
221 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
222 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
223 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
224 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
225 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
226 x "27" , x "28" , x "AF_CAN" , \
227 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
228 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
229 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
230 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
231 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
235 static const char *const af_family_key_strings[AF_MAX+1] = {
236 _sock_locks("sk_lock-")
238 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
239 _sock_locks("slock-")
241 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
242 _sock_locks("clock-")
245 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
246 _sock_locks("k-sk_lock-")
248 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
249 _sock_locks("k-slock-")
251 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
252 _sock_locks("k-clock-")
254 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
255 _sock_locks("rlock-")
257 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
258 _sock_locks("wlock-")
260 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
261 _sock_locks("elock-")
265 * sk_callback_lock and sk queues locking rules are per-address-family,
266 * so split the lock classes by using a per-AF key:
268 static struct lock_class_key af_callback_keys[AF_MAX];
269 static struct lock_class_key af_rlock_keys[AF_MAX];
270 static struct lock_class_key af_wlock_keys[AF_MAX];
271 static struct lock_class_key af_elock_keys[AF_MAX];
272 static struct lock_class_key af_kern_callback_keys[AF_MAX];
274 /* Run time adjustable parameters. */
275 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
276 EXPORT_SYMBOL(sysctl_wmem_max);
277 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
278 EXPORT_SYMBOL(sysctl_rmem_max);
279 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
280 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
282 /* Maximal space eaten by iovec or ancillary data plus some space */
283 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
284 EXPORT_SYMBOL(sysctl_optmem_max);
286 int sysctl_tstamp_allow_data __read_mostly = 1;
288 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
289 EXPORT_SYMBOL_GPL(memalloc_socks_key);
292 * sk_set_memalloc - sets %SOCK_MEMALLOC
293 * @sk: socket to set it on
295 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
296 * It's the responsibility of the admin to adjust min_free_kbytes
297 * to meet the requirements
299 void sk_set_memalloc(struct sock *sk)
301 sock_set_flag(sk, SOCK_MEMALLOC);
302 sk->sk_allocation |= __GFP_MEMALLOC;
303 static_branch_inc(&memalloc_socks_key);
305 EXPORT_SYMBOL_GPL(sk_set_memalloc);
307 void sk_clear_memalloc(struct sock *sk)
309 sock_reset_flag(sk, SOCK_MEMALLOC);
310 sk->sk_allocation &= ~__GFP_MEMALLOC;
311 static_branch_dec(&memalloc_socks_key);
314 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
315 * progress of swapping. SOCK_MEMALLOC may be cleared while
316 * it has rmem allocations due to the last swapfile being deactivated
317 * but there is a risk that the socket is unusable due to exceeding
318 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
324 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
327 unsigned int noreclaim_flag;
329 /* these should have been dropped before queueing */
330 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
332 noreclaim_flag = memalloc_noreclaim_save();
333 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 memalloc_noreclaim_restore(noreclaim_flag);
341 EXPORT_SYMBOL(__sk_backlog_rcv);
343 void sk_error_report(struct sock *sk)
345 sk->sk_error_report(sk);
347 switch (sk->sk_family) {
351 trace_inet_sk_error_report(sk);
357 EXPORT_SYMBOL(sk_error_report);
359 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
361 struct __kernel_sock_timeval tv;
363 if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 tv.tv_sec = timeo / HZ;
368 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
371 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
372 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
373 *(struct old_timeval32 *)optval = tv32;
378 struct __kernel_old_timeval old_tv;
379 old_tv.tv_sec = tv.tv_sec;
380 old_tv.tv_usec = tv.tv_usec;
381 *(struct __kernel_old_timeval *)optval = old_tv;
382 return sizeof(old_tv);
385 *(struct __kernel_sock_timeval *)optval = tv;
388 EXPORT_SYMBOL(sock_get_timeout);
390 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
391 sockptr_t optval, int optlen, bool old_timeval)
393 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
394 struct old_timeval32 tv32;
396 if (optlen < sizeof(tv32))
399 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
401 tv->tv_sec = tv32.tv_sec;
402 tv->tv_usec = tv32.tv_usec;
403 } else if (old_timeval) {
404 struct __kernel_old_timeval old_tv;
406 if (optlen < sizeof(old_tv))
408 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
410 tv->tv_sec = old_tv.tv_sec;
411 tv->tv_usec = old_tv.tv_usec;
413 if (optlen < sizeof(*tv))
415 if (copy_from_sockptr(tv, optval, sizeof(*tv)))
421 EXPORT_SYMBOL(sock_copy_user_timeval);
423 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
426 struct __kernel_sock_timeval tv;
427 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
432 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
436 static int warned __read_mostly;
439 if (warned < 10 && net_ratelimit()) {
441 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
442 __func__, current->comm, task_pid_nr(current));
446 *timeo_p = MAX_SCHEDULE_TIMEOUT;
447 if (tv.tv_sec == 0 && tv.tv_usec == 0)
449 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
450 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
454 static bool sock_needs_netstamp(const struct sock *sk)
456 switch (sk->sk_family) {
465 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
467 if (sk->sk_flags & flags) {
468 sk->sk_flags &= ~flags;
469 if (sock_needs_netstamp(sk) &&
470 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
471 net_disable_timestamp();
476 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
479 struct sk_buff_head *list = &sk->sk_receive_queue;
481 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
482 atomic_inc(&sk->sk_drops);
483 trace_sock_rcvqueue_full(sk, skb);
487 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
488 atomic_inc(&sk->sk_drops);
493 skb_set_owner_r(skb, sk);
495 /* we escape from rcu protected region, make sure we dont leak
500 spin_lock_irqsave(&list->lock, flags);
501 sock_skb_set_dropcount(sk, skb);
502 __skb_queue_tail(list, skb);
503 spin_unlock_irqrestore(&list->lock, flags);
505 if (!sock_flag(sk, SOCK_DEAD))
506 sk->sk_data_ready(sk);
509 EXPORT_SYMBOL(__sock_queue_rcv_skb);
511 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
512 enum skb_drop_reason *reason)
514 enum skb_drop_reason drop_reason;
517 err = sk_filter(sk, skb);
519 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
522 err = __sock_queue_rcv_skb(sk, skb);
525 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
528 drop_reason = SKB_DROP_REASON_PROTO_MEM;
531 drop_reason = SKB_NOT_DROPPED_YET;
536 *reason = drop_reason;
539 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
541 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
542 const int nested, unsigned int trim_cap, bool refcounted)
544 int rc = NET_RX_SUCCESS;
546 if (sk_filter_trim_cap(sk, skb, trim_cap))
547 goto discard_and_relse;
551 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
552 atomic_inc(&sk->sk_drops);
553 goto discard_and_relse;
556 bh_lock_sock_nested(sk);
559 if (!sock_owned_by_user(sk)) {
561 * trylock + unlock semantics:
563 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
565 rc = sk_backlog_rcv(sk, skb);
567 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
568 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
570 atomic_inc(&sk->sk_drops);
571 goto discard_and_relse;
583 EXPORT_SYMBOL(__sk_receive_skb);
585 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
587 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
589 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
591 struct dst_entry *dst = __sk_dst_get(sk);
593 if (dst && dst->obsolete &&
594 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
595 dst, cookie) == NULL) {
596 sk_tx_queue_clear(sk);
597 sk->sk_dst_pending_confirm = 0;
598 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
605 EXPORT_SYMBOL(__sk_dst_check);
607 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
609 struct dst_entry *dst = sk_dst_get(sk);
611 if (dst && dst->obsolete &&
612 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 dst, cookie) == NULL) {
621 EXPORT_SYMBOL(sk_dst_check);
623 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
625 int ret = -ENOPROTOOPT;
626 #ifdef CONFIG_NETDEVICES
627 struct net *net = sock_net(sk);
631 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
638 /* Paired with all READ_ONCE() done locklessly. */
639 WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
641 if (sk->sk_prot->rehash)
642 sk->sk_prot->rehash(sk);
653 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
659 ret = sock_bindtoindex_locked(sk, ifindex);
665 EXPORT_SYMBOL(sock_bindtoindex);
667 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
669 int ret = -ENOPROTOOPT;
670 #ifdef CONFIG_NETDEVICES
671 struct net *net = sock_net(sk);
672 char devname[IFNAMSIZ];
679 /* Bind this socket to a particular device like "eth0",
680 * as specified in the passed interface name. If the
681 * name is "" or the option length is zero the socket
684 if (optlen > IFNAMSIZ - 1)
685 optlen = IFNAMSIZ - 1;
686 memset(devname, 0, sizeof(devname));
689 if (copy_from_sockptr(devname, optval, optlen))
693 if (devname[0] != '\0') {
694 struct net_device *dev;
697 dev = dev_get_by_name_rcu(net, devname);
699 index = dev->ifindex;
706 sockopt_lock_sock(sk);
707 ret = sock_bindtoindex_locked(sk, index);
708 sockopt_release_sock(sk);
715 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
716 sockptr_t optlen, int len)
718 int ret = -ENOPROTOOPT;
719 #ifdef CONFIG_NETDEVICES
720 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
721 struct net *net = sock_net(sk);
722 char devname[IFNAMSIZ];
724 if (bound_dev_if == 0) {
733 ret = netdev_get_name(net, devname, bound_dev_if);
737 len = strlen(devname) + 1;
740 if (copy_to_sockptr(optval, devname, len))
745 if (copy_to_sockptr(optlen, &len, sizeof(int)))
756 bool sk_mc_loop(struct sock *sk)
758 if (dev_recursion_level())
762 switch (sk->sk_family) {
764 return inet_sk(sk)->mc_loop;
765 #if IS_ENABLED(CONFIG_IPV6)
767 return inet6_sk(sk)->mc_loop;
773 EXPORT_SYMBOL(sk_mc_loop);
775 void sock_set_reuseaddr(struct sock *sk)
778 sk->sk_reuse = SK_CAN_REUSE;
781 EXPORT_SYMBOL(sock_set_reuseaddr);
783 void sock_set_reuseport(struct sock *sk)
786 sk->sk_reuseport = true;
789 EXPORT_SYMBOL(sock_set_reuseport);
791 void sock_no_linger(struct sock *sk)
794 sk->sk_lingertime = 0;
795 sock_set_flag(sk, SOCK_LINGER);
798 EXPORT_SYMBOL(sock_no_linger);
800 void sock_set_priority(struct sock *sk, u32 priority)
803 sk->sk_priority = priority;
806 EXPORT_SYMBOL(sock_set_priority);
808 void sock_set_sndtimeo(struct sock *sk, s64 secs)
811 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
812 sk->sk_sndtimeo = secs * HZ;
814 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
817 EXPORT_SYMBOL(sock_set_sndtimeo);
819 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
822 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
823 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
824 sock_set_flag(sk, SOCK_RCVTSTAMP);
825 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
827 sock_reset_flag(sk, SOCK_RCVTSTAMP);
828 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
832 void sock_enable_timestamps(struct sock *sk)
835 __sock_set_timestamps(sk, true, false, true);
838 EXPORT_SYMBOL(sock_enable_timestamps);
840 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
843 case SO_TIMESTAMP_OLD:
844 __sock_set_timestamps(sk, valbool, false, false);
846 case SO_TIMESTAMP_NEW:
847 __sock_set_timestamps(sk, valbool, true, false);
849 case SO_TIMESTAMPNS_OLD:
850 __sock_set_timestamps(sk, valbool, false, true);
852 case SO_TIMESTAMPNS_NEW:
853 __sock_set_timestamps(sk, valbool, true, true);
858 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
860 struct net *net = sock_net(sk);
861 struct net_device *dev = NULL;
866 if (sk->sk_bound_dev_if)
867 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
870 pr_err("%s: sock not bind to device\n", __func__);
874 num = ethtool_get_phc_vclocks(dev, &vclock_index);
877 for (i = 0; i < num; i++) {
878 if (*(vclock_index + i) == phc_index) {
890 sk->sk_bind_phc = phc_index;
895 int sock_set_timestamping(struct sock *sk, int optname,
896 struct so_timestamping timestamping)
898 int val = timestamping.flags;
901 if (val & ~SOF_TIMESTAMPING_MASK)
904 if (val & SOF_TIMESTAMPING_OPT_ID &&
905 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
907 if ((1 << sk->sk_state) &
908 (TCPF_CLOSE | TCPF_LISTEN))
910 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
912 atomic_set(&sk->sk_tskey, 0);
916 if (val & SOF_TIMESTAMPING_OPT_STATS &&
917 !(val & SOF_TIMESTAMPING_OPT_TSONLY))
920 if (val & SOF_TIMESTAMPING_BIND_PHC) {
921 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
926 sk->sk_tsflags = val;
927 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
929 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
930 sock_enable_timestamp(sk,
931 SOCK_TIMESTAMPING_RX_SOFTWARE);
933 sock_disable_timestamp(sk,
934 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
938 void sock_set_keepalive(struct sock *sk)
941 if (sk->sk_prot->keepalive)
942 sk->sk_prot->keepalive(sk, true);
943 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
946 EXPORT_SYMBOL(sock_set_keepalive);
948 static void __sock_set_rcvbuf(struct sock *sk, int val)
950 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
951 * as a negative value.
953 val = min_t(int, val, INT_MAX / 2);
954 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
956 /* We double it on the way in to account for "struct sk_buff" etc.
957 * overhead. Applications assume that the SO_RCVBUF setting they make
958 * will allow that much actual data to be received on that socket.
960 * Applications are unaware that "struct sk_buff" and other overheads
961 * allocate from the receive buffer during socket buffer allocation.
963 * And after considering the possible alternatives, returning the value
964 * we actually used in getsockopt is the most desirable behavior.
966 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
969 void sock_set_rcvbuf(struct sock *sk, int val)
972 __sock_set_rcvbuf(sk, val);
975 EXPORT_SYMBOL(sock_set_rcvbuf);
977 static void __sock_set_mark(struct sock *sk, u32 val)
979 if (val != sk->sk_mark) {
985 void sock_set_mark(struct sock *sk, u32 val)
988 __sock_set_mark(sk, val);
991 EXPORT_SYMBOL(sock_set_mark);
993 static void sock_release_reserved_memory(struct sock *sk, int bytes)
995 /* Round down bytes to multiple of pages */
996 bytes = round_down(bytes, PAGE_SIZE);
998 WARN_ON(bytes > sk->sk_reserved_mem);
999 sk->sk_reserved_mem -= bytes;
1003 static int sock_reserve_memory(struct sock *sk, int bytes)
1009 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1015 pages = sk_mem_pages(bytes);
1017 /* pre-charge to memcg */
1018 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1019 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1023 /* pre-charge to forward_alloc */
1024 sk_memory_allocated_add(sk, pages);
1025 allocated = sk_memory_allocated(sk);
1026 /* If the system goes into memory pressure with this
1027 * precharge, give up and return error.
1029 if (allocated > sk_prot_mem_limits(sk, 1)) {
1030 sk_memory_allocated_sub(sk, pages);
1031 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1034 sk->sk_forward_alloc += pages << PAGE_SHIFT;
1036 sk->sk_reserved_mem += pages << PAGE_SHIFT;
1041 void sockopt_lock_sock(struct sock *sk)
1043 /* When current->bpf_ctx is set, the setsockopt is called from
1044 * a bpf prog. bpf has ensured the sk lock has been
1045 * acquired before calling setsockopt().
1047 if (has_current_bpf_ctx())
1052 EXPORT_SYMBOL(sockopt_lock_sock);
1054 void sockopt_release_sock(struct sock *sk)
1056 if (has_current_bpf_ctx())
1061 EXPORT_SYMBOL(sockopt_release_sock);
1063 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1065 return has_current_bpf_ctx() || ns_capable(ns, cap);
1067 EXPORT_SYMBOL(sockopt_ns_capable);
1069 bool sockopt_capable(int cap)
1071 return has_current_bpf_ctx() || capable(cap);
1073 EXPORT_SYMBOL(sockopt_capable);
1076 * This is meant for all protocols to use and covers goings on
1077 * at the socket level. Everything here is generic.
1080 int sk_setsockopt(struct sock *sk, int level, int optname,
1081 sockptr_t optval, unsigned int optlen)
1083 struct so_timestamping timestamping;
1084 struct socket *sock = sk->sk_socket;
1085 struct sock_txtime sk_txtime;
1092 * Options without arguments
1095 if (optname == SO_BINDTODEVICE)
1096 return sock_setbindtodevice(sk, optval, optlen);
1098 if (optlen < sizeof(int))
1101 if (copy_from_sockptr(&val, optval, sizeof(val)))
1104 valbool = val ? 1 : 0;
1106 sockopt_lock_sock(sk);
1110 if (val && !sockopt_capable(CAP_NET_ADMIN))
1113 sock_valbool_flag(sk, SOCK_DBG, valbool);
1116 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1119 sk->sk_reuseport = valbool;
1128 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1132 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1135 /* Don't error on this BSD doesn't and if you think
1136 * about it this is right. Otherwise apps have to
1137 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1138 * are treated in BSD as hints
1140 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1142 /* Ensure val * 2 fits into an int, to prevent max_t()
1143 * from treating it as a negative value.
1145 val = min_t(int, val, INT_MAX / 2);
1146 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1147 WRITE_ONCE(sk->sk_sndbuf,
1148 max_t(int, val * 2, SOCK_MIN_SNDBUF));
1149 /* Wake up sending tasks if we upped the value. */
1150 sk->sk_write_space(sk);
1153 case SO_SNDBUFFORCE:
1154 if (!sockopt_capable(CAP_NET_ADMIN)) {
1159 /* No negative values (to prevent underflow, as val will be
1167 /* Don't error on this BSD doesn't and if you think
1168 * about it this is right. Otherwise apps have to
1169 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1170 * are treated in BSD as hints
1172 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1175 case SO_RCVBUFFORCE:
1176 if (!sockopt_capable(CAP_NET_ADMIN)) {
1181 /* No negative values (to prevent underflow, as val will be
1184 __sock_set_rcvbuf(sk, max(val, 0));
1188 if (sk->sk_prot->keepalive)
1189 sk->sk_prot->keepalive(sk, valbool);
1190 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1194 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1198 sk->sk_no_check_tx = valbool;
1202 if ((val >= 0 && val <= 6) ||
1203 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1204 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1205 sk->sk_priority = val;
1211 if (optlen < sizeof(ling)) {
1212 ret = -EINVAL; /* 1003.1g */
1215 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1220 sock_reset_flag(sk, SOCK_LINGER);
1222 #if (BITS_PER_LONG == 32)
1223 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1224 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1227 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1228 sock_set_flag(sk, SOCK_LINGER);
1237 set_bit(SOCK_PASSCRED, &sock->flags);
1239 clear_bit(SOCK_PASSCRED, &sock->flags);
1242 case SO_TIMESTAMP_OLD:
1243 case SO_TIMESTAMP_NEW:
1244 case SO_TIMESTAMPNS_OLD:
1245 case SO_TIMESTAMPNS_NEW:
1246 sock_set_timestamp(sk, optname, valbool);
1249 case SO_TIMESTAMPING_NEW:
1250 case SO_TIMESTAMPING_OLD:
1251 if (optlen == sizeof(timestamping)) {
1252 if (copy_from_sockptr(×tamping, optval,
1253 sizeof(timestamping))) {
1258 memset(×tamping, 0, sizeof(timestamping));
1259 timestamping.flags = val;
1261 ret = sock_set_timestamping(sk, optname, timestamping);
1267 if (sock && sock->ops->set_rcvlowat)
1268 ret = sock->ops->set_rcvlowat(sk, val);
1270 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1273 case SO_RCVTIMEO_OLD:
1274 case SO_RCVTIMEO_NEW:
1275 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1276 optlen, optname == SO_RCVTIMEO_OLD);
1279 case SO_SNDTIMEO_OLD:
1280 case SO_SNDTIMEO_NEW:
1281 ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1282 optlen, optname == SO_SNDTIMEO_OLD);
1285 case SO_ATTACH_FILTER: {
1286 struct sock_fprog fprog;
1288 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1290 ret = sk_attach_filter(&fprog, sk);
1295 if (optlen == sizeof(u32)) {
1299 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1302 ret = sk_attach_bpf(ufd, sk);
1306 case SO_ATTACH_REUSEPORT_CBPF: {
1307 struct sock_fprog fprog;
1309 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1311 ret = sk_reuseport_attach_filter(&fprog, sk);
1314 case SO_ATTACH_REUSEPORT_EBPF:
1316 if (optlen == sizeof(u32)) {
1320 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1323 ret = sk_reuseport_attach_bpf(ufd, sk);
1327 case SO_DETACH_REUSEPORT_BPF:
1328 ret = reuseport_detach_prog(sk);
1331 case SO_DETACH_FILTER:
1332 ret = sk_detach_filter(sk);
1335 case SO_LOCK_FILTER:
1336 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1339 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1344 set_bit(SOCK_PASSSEC, &sock->flags);
1346 clear_bit(SOCK_PASSSEC, &sock->flags);
1349 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1350 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1355 __sock_set_mark(sk, val);
1358 sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1362 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1365 case SO_WIFI_STATUS:
1366 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1370 if (sock->ops->set_peek_off)
1371 ret = sock->ops->set_peek_off(sk, val);
1377 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1380 case SO_SELECT_ERR_QUEUE:
1381 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1384 #ifdef CONFIG_NET_RX_BUSY_POLL
1386 /* allow unprivileged users to decrease the value */
1387 if ((val > sk->sk_ll_usec) && !sockopt_capable(CAP_NET_ADMIN))
1393 WRITE_ONCE(sk->sk_ll_usec, val);
1396 case SO_PREFER_BUSY_POLL:
1397 if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1400 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1402 case SO_BUSY_POLL_BUDGET:
1403 if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1406 if (val < 0 || val > U16_MAX)
1409 WRITE_ONCE(sk->sk_busy_poll_budget, val);
1414 case SO_MAX_PACING_RATE:
1416 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1418 if (sizeof(ulval) != sizeof(val) &&
1419 optlen >= sizeof(ulval) &&
1420 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1425 cmpxchg(&sk->sk_pacing_status,
1428 sk->sk_max_pacing_rate = ulval;
1429 sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1432 case SO_INCOMING_CPU:
1433 reuseport_update_incoming_cpu(sk, val);
1438 dst_negative_advice(sk);
1442 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1443 if (!(sk_is_tcp(sk) ||
1444 (sk->sk_type == SOCK_DGRAM &&
1445 sk->sk_protocol == IPPROTO_UDP)))
1447 } else if (sk->sk_family != PF_RDS) {
1451 if (val < 0 || val > 1)
1454 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1459 if (optlen != sizeof(struct sock_txtime)) {
1462 } else if (copy_from_sockptr(&sk_txtime, optval,
1463 sizeof(struct sock_txtime))) {
1466 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1470 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1471 * scheduler has enough safe guards.
1473 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1474 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1478 sock_valbool_flag(sk, SOCK_TXTIME, true);
1479 sk->sk_clockid = sk_txtime.clockid;
1480 sk->sk_txtime_deadline_mode =
1481 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1482 sk->sk_txtime_report_errors =
1483 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1486 case SO_BINDTOIFINDEX:
1487 ret = sock_bindtoindex_locked(sk, val);
1491 if (val & ~SOCK_BUF_LOCK_MASK) {
1495 sk->sk_userlocks = val | (sk->sk_userlocks &
1496 ~SOCK_BUF_LOCK_MASK);
1499 case SO_RESERVE_MEM:
1508 delta = val - sk->sk_reserved_mem;
1510 sock_release_reserved_memory(sk, -delta);
1512 ret = sock_reserve_memory(sk, delta);
1517 if (val < -1 || val > 1) {
1521 if ((u8)val == SOCK_TXREHASH_DEFAULT)
1522 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1523 /* Paired with READ_ONCE() in tcp_rtx_synack() */
1524 WRITE_ONCE(sk->sk_txrehash, (u8)val);
1531 sockopt_release_sock(sk);
1535 int sock_setsockopt(struct socket *sock, int level, int optname,
1536 sockptr_t optval, unsigned int optlen)
1538 return sk_setsockopt(sock->sk, level, optname,
1541 EXPORT_SYMBOL(sock_setsockopt);
1543 static const struct cred *sk_get_peer_cred(struct sock *sk)
1545 const struct cred *cred;
1547 spin_lock(&sk->sk_peer_lock);
1548 cred = get_cred(sk->sk_peer_cred);
1549 spin_unlock(&sk->sk_peer_lock);
1554 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1555 struct ucred *ucred)
1557 ucred->pid = pid_vnr(pid);
1558 ucred->uid = ucred->gid = -1;
1560 struct user_namespace *current_ns = current_user_ns();
1562 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1563 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1567 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1569 struct user_namespace *user_ns = current_user_ns();
1572 for (i = 0; i < src->ngroups; i++) {
1573 gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1575 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1582 int sk_getsockopt(struct sock *sk, int level, int optname,
1583 sockptr_t optval, sockptr_t optlen)
1585 struct socket *sock = sk->sk_socket;
1590 unsigned long ulval;
1592 struct old_timeval32 tm32;
1593 struct __kernel_old_timeval tm;
1594 struct __kernel_sock_timeval stm;
1595 struct sock_txtime txtime;
1596 struct so_timestamping timestamping;
1599 int lv = sizeof(int);
1602 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1607 memset(&v, 0, sizeof(v));
1611 v.val = sock_flag(sk, SOCK_DBG);
1615 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1619 v.val = sock_flag(sk, SOCK_BROADCAST);
1623 v.val = sk->sk_sndbuf;
1627 v.val = sk->sk_rcvbuf;
1631 v.val = sk->sk_reuse;
1635 v.val = sk->sk_reuseport;
1639 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1643 v.val = sk->sk_type;
1647 v.val = sk->sk_protocol;
1651 v.val = sk->sk_family;
1655 v.val = -sock_error(sk);
1657 v.val = xchg(&sk->sk_err_soft, 0);
1661 v.val = sock_flag(sk, SOCK_URGINLINE);
1665 v.val = sk->sk_no_check_tx;
1669 v.val = sk->sk_priority;
1673 lv = sizeof(v.ling);
1674 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1675 v.ling.l_linger = sk->sk_lingertime / HZ;
1681 case SO_TIMESTAMP_OLD:
1682 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1683 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1684 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1687 case SO_TIMESTAMPNS_OLD:
1688 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1691 case SO_TIMESTAMP_NEW:
1692 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1695 case SO_TIMESTAMPNS_NEW:
1696 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1699 case SO_TIMESTAMPING_OLD:
1700 lv = sizeof(v.timestamping);
1701 v.timestamping.flags = sk->sk_tsflags;
1702 v.timestamping.bind_phc = sk->sk_bind_phc;
1705 case SO_RCVTIMEO_OLD:
1706 case SO_RCVTIMEO_NEW:
1707 lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1710 case SO_SNDTIMEO_OLD:
1711 case SO_SNDTIMEO_NEW:
1712 lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1716 v.val = sk->sk_rcvlowat;
1724 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1729 struct ucred peercred;
1730 if (len > sizeof(peercred))
1731 len = sizeof(peercred);
1733 spin_lock(&sk->sk_peer_lock);
1734 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1735 spin_unlock(&sk->sk_peer_lock);
1737 if (copy_to_sockptr(optval, &peercred, len))
1744 const struct cred *cred;
1747 cred = sk_get_peer_cred(sk);
1751 n = cred->group_info->ngroups;
1752 if (len < n * sizeof(gid_t)) {
1753 len = n * sizeof(gid_t);
1755 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1757 len = n * sizeof(gid_t);
1759 ret = groups_to_user(optval, cred->group_info);
1770 lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1775 if (copy_to_sockptr(optval, address, len))
1780 /* Dubious BSD thing... Probably nobody even uses it, but
1781 * the UNIX standard wants it for whatever reason... -DaveM
1784 v.val = sk->sk_state == TCP_LISTEN;
1788 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1792 return security_socket_getpeersec_stream(sock, optval.user, optlen.user, len);
1795 v.val = sk->sk_mark;
1799 v.val = sock_flag(sk, SOCK_RCVMARK);
1803 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1806 case SO_WIFI_STATUS:
1807 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1811 if (!sock->ops->set_peek_off)
1814 v.val = sk->sk_peek_off;
1817 v.val = sock_flag(sk, SOCK_NOFCS);
1820 case SO_BINDTODEVICE:
1821 return sock_getbindtodevice(sk, optval, optlen, len);
1824 len = sk_get_filter(sk, optval, len);
1830 case SO_LOCK_FILTER:
1831 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1834 case SO_BPF_EXTENSIONS:
1835 v.val = bpf_tell_extensions();
1838 case SO_SELECT_ERR_QUEUE:
1839 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1842 #ifdef CONFIG_NET_RX_BUSY_POLL
1844 v.val = sk->sk_ll_usec;
1846 case SO_PREFER_BUSY_POLL:
1847 v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1851 case SO_MAX_PACING_RATE:
1852 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1853 lv = sizeof(v.ulval);
1854 v.ulval = sk->sk_max_pacing_rate;
1857 v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1861 case SO_INCOMING_CPU:
1862 v.val = READ_ONCE(sk->sk_incoming_cpu);
1867 u32 meminfo[SK_MEMINFO_VARS];
1869 sk_get_meminfo(sk, meminfo);
1871 len = min_t(unsigned int, len, sizeof(meminfo));
1872 if (copy_to_sockptr(optval, &meminfo, len))
1878 #ifdef CONFIG_NET_RX_BUSY_POLL
1879 case SO_INCOMING_NAPI_ID:
1880 v.val = READ_ONCE(sk->sk_napi_id);
1882 /* aggregate non-NAPI IDs down to 0 */
1883 if (v.val < MIN_NAPI_ID)
1893 v.val64 = sock_gen_cookie(sk);
1897 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1901 lv = sizeof(v.txtime);
1902 v.txtime.clockid = sk->sk_clockid;
1903 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1904 SOF_TXTIME_DEADLINE_MODE : 0;
1905 v.txtime.flags |= sk->sk_txtime_report_errors ?
1906 SOF_TXTIME_REPORT_ERRORS : 0;
1909 case SO_BINDTOIFINDEX:
1910 v.val = READ_ONCE(sk->sk_bound_dev_if);
1913 case SO_NETNS_COOKIE:
1917 v.val64 = sock_net(sk)->net_cookie;
1921 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1924 case SO_RESERVE_MEM:
1925 v.val = sk->sk_reserved_mem;
1929 v.val = sk->sk_txrehash;
1933 /* We implement the SO_SNDLOWAT etc to not be settable
1936 return -ENOPROTOOPT;
1941 if (copy_to_sockptr(optval, &v, len))
1944 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1949 int sock_getsockopt(struct socket *sock, int level, int optname,
1950 char __user *optval, int __user *optlen)
1952 return sk_getsockopt(sock->sk, level, optname,
1953 USER_SOCKPTR(optval),
1954 USER_SOCKPTR(optlen));
1958 * Initialize an sk_lock.
1960 * (We also register the sk_lock with the lock validator.)
1962 static inline void sock_lock_init(struct sock *sk)
1964 if (sk->sk_kern_sock)
1965 sock_lock_init_class_and_name(
1967 af_family_kern_slock_key_strings[sk->sk_family],
1968 af_family_kern_slock_keys + sk->sk_family,
1969 af_family_kern_key_strings[sk->sk_family],
1970 af_family_kern_keys + sk->sk_family);
1972 sock_lock_init_class_and_name(
1974 af_family_slock_key_strings[sk->sk_family],
1975 af_family_slock_keys + sk->sk_family,
1976 af_family_key_strings[sk->sk_family],
1977 af_family_keys + sk->sk_family);
1981 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1982 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1983 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1985 static void sock_copy(struct sock *nsk, const struct sock *osk)
1987 const struct proto *prot = READ_ONCE(osk->sk_prot);
1988 #ifdef CONFIG_SECURITY_NETWORK
1989 void *sptr = nsk->sk_security;
1992 /* If we move sk_tx_queue_mapping out of the private section,
1993 * we must check if sk_tx_queue_clear() is called after
1994 * sock_copy() in sk_clone_lock().
1996 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
1997 offsetof(struct sock, sk_dontcopy_begin) ||
1998 offsetof(struct sock, sk_tx_queue_mapping) >=
1999 offsetof(struct sock, sk_dontcopy_end));
2001 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2003 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2004 prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2006 #ifdef CONFIG_SECURITY_NETWORK
2007 nsk->sk_security = sptr;
2008 security_sk_clone(osk, nsk);
2012 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2016 struct kmem_cache *slab;
2020 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2023 if (want_init_on_alloc(priority))
2024 sk_prot_clear_nulls(sk, prot->obj_size);
2026 sk = kmalloc(prot->obj_size, priority);
2029 if (security_sk_alloc(sk, family, priority))
2032 if (!try_module_get(prot->owner))
2039 security_sk_free(sk);
2042 kmem_cache_free(slab, sk);
2048 static void sk_prot_free(struct proto *prot, struct sock *sk)
2050 struct kmem_cache *slab;
2051 struct module *owner;
2053 owner = prot->owner;
2056 cgroup_sk_free(&sk->sk_cgrp_data);
2057 mem_cgroup_sk_free(sk);
2058 security_sk_free(sk);
2060 kmem_cache_free(slab, sk);
2067 * sk_alloc - All socket objects are allocated here
2068 * @net: the applicable net namespace
2069 * @family: protocol family
2070 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2071 * @prot: struct proto associated with this new sock instance
2072 * @kern: is this to be a kernel socket?
2074 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2075 struct proto *prot, int kern)
2079 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2081 sk->sk_family = family;
2083 * See comment in struct sock definition to understand
2084 * why we need sk_prot_creator -acme
2086 sk->sk_prot = sk->sk_prot_creator = prot;
2087 sk->sk_kern_sock = kern;
2089 sk->sk_net_refcnt = kern ? 0 : 1;
2090 if (likely(sk->sk_net_refcnt)) {
2091 get_net_track(net, &sk->ns_tracker, priority);
2092 sock_inuse_add(net, 1);
2095 sock_net_set(sk, net);
2096 refcount_set(&sk->sk_wmem_alloc, 1);
2098 mem_cgroup_sk_alloc(sk);
2099 cgroup_sk_alloc(&sk->sk_cgrp_data);
2100 sock_update_classid(&sk->sk_cgrp_data);
2101 sock_update_netprioidx(&sk->sk_cgrp_data);
2102 sk_tx_queue_clear(sk);
2107 EXPORT_SYMBOL(sk_alloc);
2109 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2110 * grace period. This is the case for UDP sockets and TCP listeners.
2112 static void __sk_destruct(struct rcu_head *head)
2114 struct sock *sk = container_of(head, struct sock, sk_rcu);
2115 struct sk_filter *filter;
2117 if (sk->sk_destruct)
2118 sk->sk_destruct(sk);
2120 filter = rcu_dereference_check(sk->sk_filter,
2121 refcount_read(&sk->sk_wmem_alloc) == 0);
2123 sk_filter_uncharge(sk, filter);
2124 RCU_INIT_POINTER(sk->sk_filter, NULL);
2127 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2129 #ifdef CONFIG_BPF_SYSCALL
2130 bpf_sk_storage_free(sk);
2133 if (atomic_read(&sk->sk_omem_alloc))
2134 pr_debug("%s: optmem leakage (%d bytes) detected\n",
2135 __func__, atomic_read(&sk->sk_omem_alloc));
2137 if (sk->sk_frag.page) {
2138 put_page(sk->sk_frag.page);
2139 sk->sk_frag.page = NULL;
2142 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2143 put_cred(sk->sk_peer_cred);
2144 put_pid(sk->sk_peer_pid);
2146 if (likely(sk->sk_net_refcnt))
2147 put_net_track(sock_net(sk), &sk->ns_tracker);
2148 sk_prot_free(sk->sk_prot_creator, sk);
2151 void sk_destruct(struct sock *sk)
2153 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2155 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2156 reuseport_detach_sock(sk);
2157 use_call_rcu = true;
2161 call_rcu(&sk->sk_rcu, __sk_destruct);
2163 __sk_destruct(&sk->sk_rcu);
2166 static void __sk_free(struct sock *sk)
2168 if (likely(sk->sk_net_refcnt))
2169 sock_inuse_add(sock_net(sk), -1);
2171 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2172 sock_diag_broadcast_destroy(sk);
2177 void sk_free(struct sock *sk)
2180 * We subtract one from sk_wmem_alloc and can know if
2181 * some packets are still in some tx queue.
2182 * If not null, sock_wfree() will call __sk_free(sk) later
2184 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2187 EXPORT_SYMBOL(sk_free);
2189 static void sk_init_common(struct sock *sk)
2191 skb_queue_head_init(&sk->sk_receive_queue);
2192 skb_queue_head_init(&sk->sk_write_queue);
2193 skb_queue_head_init(&sk->sk_error_queue);
2195 rwlock_init(&sk->sk_callback_lock);
2196 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2197 af_rlock_keys + sk->sk_family,
2198 af_family_rlock_key_strings[sk->sk_family]);
2199 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2200 af_wlock_keys + sk->sk_family,
2201 af_family_wlock_key_strings[sk->sk_family]);
2202 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2203 af_elock_keys + sk->sk_family,
2204 af_family_elock_key_strings[sk->sk_family]);
2205 lockdep_set_class_and_name(&sk->sk_callback_lock,
2206 af_callback_keys + sk->sk_family,
2207 af_family_clock_key_strings[sk->sk_family]);
2211 * sk_clone_lock - clone a socket, and lock its clone
2212 * @sk: the socket to clone
2213 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2215 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2217 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2219 struct proto *prot = READ_ONCE(sk->sk_prot);
2220 struct sk_filter *filter;
2221 bool is_charged = true;
2224 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2228 sock_copy(newsk, sk);
2230 newsk->sk_prot_creator = prot;
2233 if (likely(newsk->sk_net_refcnt)) {
2234 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2235 sock_inuse_add(sock_net(newsk), 1);
2237 sk_node_init(&newsk->sk_node);
2238 sock_lock_init(newsk);
2239 bh_lock_sock(newsk);
2240 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
2241 newsk->sk_backlog.len = 0;
2243 atomic_set(&newsk->sk_rmem_alloc, 0);
2245 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2246 refcount_set(&newsk->sk_wmem_alloc, 1);
2248 atomic_set(&newsk->sk_omem_alloc, 0);
2249 sk_init_common(newsk);
2251 newsk->sk_dst_cache = NULL;
2252 newsk->sk_dst_pending_confirm = 0;
2253 newsk->sk_wmem_queued = 0;
2254 newsk->sk_forward_alloc = 0;
2255 newsk->sk_reserved_mem = 0;
2256 atomic_set(&newsk->sk_drops, 0);
2257 newsk->sk_send_head = NULL;
2258 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2259 atomic_set(&newsk->sk_zckey, 0);
2261 sock_reset_flag(newsk, SOCK_DONE);
2263 /* sk->sk_memcg will be populated at accept() time */
2264 newsk->sk_memcg = NULL;
2266 cgroup_sk_clone(&newsk->sk_cgrp_data);
2269 filter = rcu_dereference(sk->sk_filter);
2271 /* though it's an empty new sock, the charging may fail
2272 * if sysctl_optmem_max was changed between creation of
2273 * original socket and cloning
2275 is_charged = sk_filter_charge(newsk, filter);
2276 RCU_INIT_POINTER(newsk->sk_filter, filter);
2279 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2280 /* We need to make sure that we don't uncharge the new
2281 * socket if we couldn't charge it in the first place
2282 * as otherwise we uncharge the parent's filter.
2285 RCU_INIT_POINTER(newsk->sk_filter, NULL);
2286 sk_free_unlock_clone(newsk);
2290 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2292 if (bpf_sk_storage_clone(sk, newsk)) {
2293 sk_free_unlock_clone(newsk);
2298 /* Clear sk_user_data if parent had the pointer tagged
2299 * as not suitable for copying when cloning.
2301 if (sk_user_data_is_nocopy(newsk))
2302 newsk->sk_user_data = NULL;
2305 newsk->sk_err_soft = 0;
2306 newsk->sk_priority = 0;
2307 newsk->sk_incoming_cpu = raw_smp_processor_id();
2309 /* Before updating sk_refcnt, we must commit prior changes to memory
2310 * (Documentation/RCU/rculist_nulls.rst for details)
2313 refcount_set(&newsk->sk_refcnt, 2);
2315 /* Increment the counter in the same struct proto as the master
2316 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2317 * is the same as sk->sk_prot->socks, as this field was copied
2320 * This _changes_ the previous behaviour, where
2321 * tcp_create_openreq_child always was incrementing the
2322 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2323 * to be taken into account in all callers. -acme
2325 sk_refcnt_debug_inc(newsk);
2326 sk_set_socket(newsk, NULL);
2327 sk_tx_queue_clear(newsk);
2328 RCU_INIT_POINTER(newsk->sk_wq, NULL);
2330 if (newsk->sk_prot->sockets_allocated)
2331 sk_sockets_allocated_inc(newsk);
2333 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2334 net_enable_timestamp();
2338 EXPORT_SYMBOL_GPL(sk_clone_lock);
2340 void sk_free_unlock_clone(struct sock *sk)
2342 /* It is still raw copy of parent, so invalidate
2343 * destructor and make plain sk_free() */
2344 sk->sk_destruct = NULL;
2348 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2350 static void sk_trim_gso_size(struct sock *sk)
2352 if (sk->sk_gso_max_size <= GSO_LEGACY_MAX_SIZE)
2354 #if IS_ENABLED(CONFIG_IPV6)
2355 if (sk->sk_family == AF_INET6 &&
2357 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
2360 sk->sk_gso_max_size = GSO_LEGACY_MAX_SIZE;
2363 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2367 sk->sk_route_caps = dst->dev->features;
2369 sk->sk_route_caps |= NETIF_F_GSO;
2370 if (sk->sk_route_caps & NETIF_F_GSO)
2371 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2372 if (unlikely(sk->sk_gso_disabled))
2373 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2374 if (sk_can_gso(sk)) {
2375 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2376 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2378 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2379 /* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2380 sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2381 sk_trim_gso_size(sk);
2382 sk->sk_gso_max_size -= (MAX_TCP_HEADER + 1);
2383 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2384 max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2387 sk->sk_gso_max_segs = max_segs;
2388 sk_dst_set(sk, dst);
2390 EXPORT_SYMBOL_GPL(sk_setup_caps);
2393 * Simple resource managers for sockets.
2398 * Write buffer destructor automatically called from kfree_skb.
2400 void sock_wfree(struct sk_buff *skb)
2402 struct sock *sk = skb->sk;
2403 unsigned int len = skb->truesize;
2406 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2407 if (sock_flag(sk, SOCK_RCU_FREE) &&
2408 sk->sk_write_space == sock_def_write_space) {
2410 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2411 sock_def_write_space_wfree(sk);
2419 * Keep a reference on sk_wmem_alloc, this will be released
2420 * after sk_write_space() call
2422 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2423 sk->sk_write_space(sk);
2427 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2428 * could not do because of in-flight packets
2430 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2433 EXPORT_SYMBOL(sock_wfree);
2435 /* This variant of sock_wfree() is used by TCP,
2436 * since it sets SOCK_USE_WRITE_QUEUE.
2438 void __sock_wfree(struct sk_buff *skb)
2440 struct sock *sk = skb->sk;
2442 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2446 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2451 if (unlikely(!sk_fullsock(sk))) {
2452 skb->destructor = sock_edemux;
2457 skb->destructor = sock_wfree;
2458 skb_set_hash_from_sk(skb, sk);
2460 * We used to take a refcount on sk, but following operation
2461 * is enough to guarantee sk_free() wont free this sock until
2462 * all in-flight packets are completed
2464 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2466 EXPORT_SYMBOL(skb_set_owner_w);
2468 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2470 #ifdef CONFIG_TLS_DEVICE
2471 /* Drivers depend on in-order delivery for crypto offload,
2472 * partial orphan breaks out-of-order-OK logic.
2477 return (skb->destructor == sock_wfree ||
2478 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2481 /* This helper is used by netem, as it can hold packets in its
2482 * delay queue. We want to allow the owner socket to send more
2483 * packets, as if they were already TX completed by a typical driver.
2484 * But we also want to keep skb->sk set because some packet schedulers
2485 * rely on it (sch_fq for example).
2487 void skb_orphan_partial(struct sk_buff *skb)
2489 if (skb_is_tcp_pure_ack(skb))
2492 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2497 EXPORT_SYMBOL(skb_orphan_partial);
2500 * Read buffer destructor automatically called from kfree_skb.
2502 void sock_rfree(struct sk_buff *skb)
2504 struct sock *sk = skb->sk;
2505 unsigned int len = skb->truesize;
2507 atomic_sub(len, &sk->sk_rmem_alloc);
2508 sk_mem_uncharge(sk, len);
2510 EXPORT_SYMBOL(sock_rfree);
2513 * Buffer destructor for skbs that are not used directly in read or write
2514 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2516 void sock_efree(struct sk_buff *skb)
2520 EXPORT_SYMBOL(sock_efree);
2522 /* Buffer destructor for prefetch/receive path where reference count may
2523 * not be held, e.g. for listen sockets.
2526 void sock_pfree(struct sk_buff *skb)
2528 if (sk_is_refcounted(skb->sk))
2529 sock_gen_put(skb->sk);
2531 EXPORT_SYMBOL(sock_pfree);
2532 #endif /* CONFIG_INET */
2534 kuid_t sock_i_uid(struct sock *sk)
2538 read_lock_bh(&sk->sk_callback_lock);
2539 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2540 read_unlock_bh(&sk->sk_callback_lock);
2543 EXPORT_SYMBOL(sock_i_uid);
2545 unsigned long __sock_i_ino(struct sock *sk)
2549 read_lock(&sk->sk_callback_lock);
2550 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2551 read_unlock(&sk->sk_callback_lock);
2554 EXPORT_SYMBOL(__sock_i_ino);
2556 unsigned long sock_i_ino(struct sock *sk)
2561 ino = __sock_i_ino(sk);
2565 EXPORT_SYMBOL(sock_i_ino);
2568 * Allocate a skb from the socket's send buffer.
2570 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2574 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2575 struct sk_buff *skb = alloc_skb(size, priority);
2578 skb_set_owner_w(skb, sk);
2584 EXPORT_SYMBOL(sock_wmalloc);
2586 static void sock_ofree(struct sk_buff *skb)
2588 struct sock *sk = skb->sk;
2590 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2593 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2596 struct sk_buff *skb;
2598 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2599 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2600 READ_ONCE(sysctl_optmem_max))
2603 skb = alloc_skb(size, priority);
2607 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2609 skb->destructor = sock_ofree;
2614 * Allocate a memory block from the socket's option memory buffer.
2616 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2618 int optmem_max = READ_ONCE(sysctl_optmem_max);
2620 if ((unsigned int)size <= optmem_max &&
2621 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2623 /* First do the add, to avoid the race if kmalloc
2626 atomic_add(size, &sk->sk_omem_alloc);
2627 mem = kmalloc(size, priority);
2630 atomic_sub(size, &sk->sk_omem_alloc);
2634 EXPORT_SYMBOL(sock_kmalloc);
2636 /* Free an option memory block. Note, we actually want the inline
2637 * here as this allows gcc to detect the nullify and fold away the
2638 * condition entirely.
2640 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2643 if (WARN_ON_ONCE(!mem))
2646 kfree_sensitive(mem);
2649 atomic_sub(size, &sk->sk_omem_alloc);
2652 void sock_kfree_s(struct sock *sk, void *mem, int size)
2654 __sock_kfree_s(sk, mem, size, false);
2656 EXPORT_SYMBOL(sock_kfree_s);
2658 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2660 __sock_kfree_s(sk, mem, size, true);
2662 EXPORT_SYMBOL(sock_kzfree_s);
2664 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2665 I think, these locks should be removed for datagram sockets.
2667 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2671 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2675 if (signal_pending(current))
2677 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2678 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2679 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2681 if (sk->sk_shutdown & SEND_SHUTDOWN)
2685 timeo = schedule_timeout(timeo);
2687 finish_wait(sk_sleep(sk), &wait);
2693 * Generic send/receive buffer handlers
2696 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2697 unsigned long data_len, int noblock,
2698 int *errcode, int max_page_order)
2700 struct sk_buff *skb;
2704 timeo = sock_sndtimeo(sk, noblock);
2706 err = sock_error(sk);
2711 if (sk->sk_shutdown & SEND_SHUTDOWN)
2714 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2717 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2718 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2722 if (signal_pending(current))
2724 timeo = sock_wait_for_wmem(sk, timeo);
2726 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2727 errcode, sk->sk_allocation);
2729 skb_set_owner_w(skb, sk);
2733 err = sock_intr_errno(timeo);
2738 EXPORT_SYMBOL(sock_alloc_send_pskb);
2740 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2741 struct sockcm_cookie *sockc)
2745 switch (cmsg->cmsg_type) {
2747 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2748 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2750 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2752 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2754 case SO_TIMESTAMPING_OLD:
2755 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2758 tsflags = *(u32 *)CMSG_DATA(cmsg);
2759 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2762 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2763 sockc->tsflags |= tsflags;
2766 if (!sock_flag(sk, SOCK_TXTIME))
2768 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2770 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2772 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2774 case SCM_CREDENTIALS:
2781 EXPORT_SYMBOL(__sock_cmsg_send);
2783 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2784 struct sockcm_cookie *sockc)
2786 struct cmsghdr *cmsg;
2789 for_each_cmsghdr(cmsg, msg) {
2790 if (!CMSG_OK(msg, cmsg))
2792 if (cmsg->cmsg_level != SOL_SOCKET)
2794 ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2800 EXPORT_SYMBOL(sock_cmsg_send);
2802 static void sk_enter_memory_pressure(struct sock *sk)
2804 if (!sk->sk_prot->enter_memory_pressure)
2807 sk->sk_prot->enter_memory_pressure(sk);
2810 static void sk_leave_memory_pressure(struct sock *sk)
2812 if (sk->sk_prot->leave_memory_pressure) {
2813 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2814 tcp_leave_memory_pressure, sk);
2816 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2818 if (memory_pressure && READ_ONCE(*memory_pressure))
2819 WRITE_ONCE(*memory_pressure, 0);
2823 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2826 * skb_page_frag_refill - check that a page_frag contains enough room
2827 * @sz: minimum size of the fragment we want to get
2828 * @pfrag: pointer to page_frag
2829 * @gfp: priority for memory allocation
2831 * Note: While this allocator tries to use high order pages, there is
2832 * no guarantee that allocations succeed. Therefore, @sz MUST be
2833 * less or equal than PAGE_SIZE.
2835 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2838 if (page_ref_count(pfrag->page) == 1) {
2842 if (pfrag->offset + sz <= pfrag->size)
2844 put_page(pfrag->page);
2848 if (SKB_FRAG_PAGE_ORDER &&
2849 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2850 /* Avoid direct reclaim but allow kswapd to wake */
2851 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2852 __GFP_COMP | __GFP_NOWARN |
2854 SKB_FRAG_PAGE_ORDER);
2855 if (likely(pfrag->page)) {
2856 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2860 pfrag->page = alloc_page(gfp);
2861 if (likely(pfrag->page)) {
2862 pfrag->size = PAGE_SIZE;
2867 EXPORT_SYMBOL(skb_page_frag_refill);
2869 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2871 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2874 sk_enter_memory_pressure(sk);
2875 sk_stream_moderate_sndbuf(sk);
2878 EXPORT_SYMBOL(sk_page_frag_refill);
2880 void __lock_sock(struct sock *sk)
2881 __releases(&sk->sk_lock.slock)
2882 __acquires(&sk->sk_lock.slock)
2887 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2888 TASK_UNINTERRUPTIBLE);
2889 spin_unlock_bh(&sk->sk_lock.slock);
2891 spin_lock_bh(&sk->sk_lock.slock);
2892 if (!sock_owned_by_user(sk))
2895 finish_wait(&sk->sk_lock.wq, &wait);
2898 void __release_sock(struct sock *sk)
2899 __releases(&sk->sk_lock.slock)
2900 __acquires(&sk->sk_lock.slock)
2902 struct sk_buff *skb, *next;
2904 while ((skb = sk->sk_backlog.head) != NULL) {
2905 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2907 spin_unlock_bh(&sk->sk_lock.slock);
2912 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2913 skb_mark_not_on_list(skb);
2914 sk_backlog_rcv(sk, skb);
2919 } while (skb != NULL);
2921 spin_lock_bh(&sk->sk_lock.slock);
2925 * Doing the zeroing here guarantee we can not loop forever
2926 * while a wild producer attempts to flood us.
2928 sk->sk_backlog.len = 0;
2931 void __sk_flush_backlog(struct sock *sk)
2933 spin_lock_bh(&sk->sk_lock.slock);
2935 spin_unlock_bh(&sk->sk_lock.slock);
2937 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2940 * sk_wait_data - wait for data to arrive at sk_receive_queue
2941 * @sk: sock to wait on
2942 * @timeo: for how long
2943 * @skb: last skb seen on sk_receive_queue
2945 * Now socket state including sk->sk_err is changed only under lock,
2946 * hence we may omit checks after joining wait queue.
2947 * We check receive queue before schedule() only as optimization;
2948 * it is very likely that release_sock() added new data.
2950 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2952 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2955 add_wait_queue(sk_sleep(sk), &wait);
2956 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2957 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2958 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2959 remove_wait_queue(sk_sleep(sk), &wait);
2962 EXPORT_SYMBOL(sk_wait_data);
2965 * __sk_mem_raise_allocated - increase memory_allocated
2967 * @size: memory size to allocate
2968 * @amt: pages to allocate
2969 * @kind: allocation type
2971 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2973 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2975 bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2976 struct proto *prot = sk->sk_prot;
2977 bool charged = true;
2980 sk_memory_allocated_add(sk, amt);
2981 allocated = sk_memory_allocated(sk);
2983 !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2984 gfp_memcg_charge())))
2985 goto suppress_allocation;
2988 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2989 sk_leave_memory_pressure(sk);
2993 /* Under pressure. */
2994 if (allocated > sk_prot_mem_limits(sk, 1))
2995 sk_enter_memory_pressure(sk);
2997 /* Over hard limit. */
2998 if (allocated > sk_prot_mem_limits(sk, 2))
2999 goto suppress_allocation;
3001 /* guarantee minimum buffer size under pressure */
3002 if (kind == SK_MEM_RECV) {
3003 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3006 } else { /* SK_MEM_SEND */
3007 int wmem0 = sk_get_wmem0(sk, prot);
3009 if (sk->sk_type == SOCK_STREAM) {
3010 if (sk->sk_wmem_queued < wmem0)
3012 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3017 if (sk_has_memory_pressure(sk)) {
3020 if (!sk_under_memory_pressure(sk))
3022 alloc = sk_sockets_allocated_read_positive(sk);
3023 if (sk_prot_mem_limits(sk, 2) > alloc *
3024 sk_mem_pages(sk->sk_wmem_queued +
3025 atomic_read(&sk->sk_rmem_alloc) +
3026 sk->sk_forward_alloc))
3030 suppress_allocation:
3032 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3033 sk_stream_moderate_sndbuf(sk);
3035 /* Fail only if socket is _under_ its sndbuf.
3036 * In this case we cannot block, so that we have to fail.
3038 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3039 /* Force charge with __GFP_NOFAIL */
3040 if (memcg_charge && !charged) {
3041 mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3042 gfp_memcg_charge() | __GFP_NOFAIL);
3048 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3049 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3051 sk_memory_allocated_sub(sk, amt);
3053 if (memcg_charge && charged)
3054 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3060 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3062 * @size: memory size to allocate
3063 * @kind: allocation type
3065 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3066 * rmem allocation. This function assumes that protocols which have
3067 * memory_pressure use sk_wmem_queued as write buffer accounting.
3069 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3071 int ret, amt = sk_mem_pages(size);
3073 sk->sk_forward_alloc += amt << PAGE_SHIFT;
3074 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3076 sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3079 EXPORT_SYMBOL(__sk_mem_schedule);
3082 * __sk_mem_reduce_allocated - reclaim memory_allocated
3084 * @amount: number of quanta
3086 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3088 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3090 sk_memory_allocated_sub(sk, amount);
3092 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3093 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3095 if (sk_under_memory_pressure(sk) &&
3096 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3097 sk_leave_memory_pressure(sk);
3101 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3103 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3105 void __sk_mem_reclaim(struct sock *sk, int amount)
3107 amount >>= PAGE_SHIFT;
3108 sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3109 __sk_mem_reduce_allocated(sk, amount);
3111 EXPORT_SYMBOL(__sk_mem_reclaim);
3113 int sk_set_peek_off(struct sock *sk, int val)
3115 sk->sk_peek_off = val;
3118 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3121 * Set of default routines for initialising struct proto_ops when
3122 * the protocol does not support a particular function. In certain
3123 * cases where it makes no sense for a protocol to have a "do nothing"
3124 * function, some default processing is provided.
3127 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3131 EXPORT_SYMBOL(sock_no_bind);
3133 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3138 EXPORT_SYMBOL(sock_no_connect);
3140 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3144 EXPORT_SYMBOL(sock_no_socketpair);
3146 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3151 EXPORT_SYMBOL(sock_no_accept);
3153 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3158 EXPORT_SYMBOL(sock_no_getname);
3160 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3164 EXPORT_SYMBOL(sock_no_ioctl);
3166 int sock_no_listen(struct socket *sock, int backlog)
3170 EXPORT_SYMBOL(sock_no_listen);
3172 int sock_no_shutdown(struct socket *sock, int how)
3176 EXPORT_SYMBOL(sock_no_shutdown);
3178 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3182 EXPORT_SYMBOL(sock_no_sendmsg);
3184 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3188 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3190 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3195 EXPORT_SYMBOL(sock_no_recvmsg);
3197 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3199 /* Mirror missing mmap method error code */
3202 EXPORT_SYMBOL(sock_no_mmap);
3205 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3206 * various sock-based usage counts.
3208 void __receive_sock(struct file *file)
3210 struct socket *sock;
3212 sock = sock_from_file(file);
3214 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3215 sock_update_classid(&sock->sk->sk_cgrp_data);
3219 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3222 struct msghdr msg = {.msg_flags = flags};
3224 char *kaddr = kmap(page);
3225 iov.iov_base = kaddr + offset;
3227 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3231 EXPORT_SYMBOL(sock_no_sendpage);
3233 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3234 int offset, size_t size, int flags)
3237 struct msghdr msg = {.msg_flags = flags};
3239 char *kaddr = kmap(page);
3241 iov.iov_base = kaddr + offset;
3243 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3247 EXPORT_SYMBOL(sock_no_sendpage_locked);
3250 * Default Socket Callbacks
3253 static void sock_def_wakeup(struct sock *sk)
3255 struct socket_wq *wq;
3258 wq = rcu_dereference(sk->sk_wq);
3259 if (skwq_has_sleeper(wq))
3260 wake_up_interruptible_all(&wq->wait);
3264 static void sock_def_error_report(struct sock *sk)
3266 struct socket_wq *wq;
3269 wq = rcu_dereference(sk->sk_wq);
3270 if (skwq_has_sleeper(wq))
3271 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3272 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3276 void sock_def_readable(struct sock *sk)
3278 struct socket_wq *wq;
3281 wq = rcu_dereference(sk->sk_wq);
3282 if (skwq_has_sleeper(wq))
3283 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3284 EPOLLRDNORM | EPOLLRDBAND);
3285 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3289 static void sock_def_write_space(struct sock *sk)
3291 struct socket_wq *wq;
3295 /* Do not wake up a writer until he can make "significant"
3298 if (sock_writeable(sk)) {
3299 wq = rcu_dereference(sk->sk_wq);
3300 if (skwq_has_sleeper(wq))
3301 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3302 EPOLLWRNORM | EPOLLWRBAND);
3304 /* Should agree with poll, otherwise some programs break */
3305 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3311 /* An optimised version of sock_def_write_space(), should only be called
3312 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3315 static void sock_def_write_space_wfree(struct sock *sk)
3317 /* Do not wake up a writer until he can make "significant"
3320 if (sock_writeable(sk)) {
3321 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3323 /* rely on refcount_sub from sock_wfree() */
3324 smp_mb__after_atomic();
3325 if (wq && waitqueue_active(&wq->wait))
3326 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3327 EPOLLWRNORM | EPOLLWRBAND);
3329 /* Should agree with poll, otherwise some programs break */
3330 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3334 static void sock_def_destruct(struct sock *sk)
3338 void sk_send_sigurg(struct sock *sk)
3340 if (sk->sk_socket && sk->sk_socket->file)
3341 if (send_sigurg(&sk->sk_socket->file->f_owner))
3342 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3344 EXPORT_SYMBOL(sk_send_sigurg);
3346 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3347 unsigned long expires)
3349 if (!mod_timer(timer, expires))
3352 EXPORT_SYMBOL(sk_reset_timer);
3354 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3356 if (del_timer(timer))
3359 EXPORT_SYMBOL(sk_stop_timer);
3361 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3363 if (del_timer_sync(timer))
3366 EXPORT_SYMBOL(sk_stop_timer_sync);
3368 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3371 sk->sk_send_head = NULL;
3373 timer_setup(&sk->sk_timer, NULL, 0);
3375 sk->sk_allocation = GFP_KERNEL;
3376 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default);
3377 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default);
3378 sk->sk_state = TCP_CLOSE;
3379 sk_set_socket(sk, sock);
3381 sock_set_flag(sk, SOCK_ZAPPED);
3384 sk->sk_type = sock->type;
3385 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3388 RCU_INIT_POINTER(sk->sk_wq, NULL);
3392 rwlock_init(&sk->sk_callback_lock);
3393 if (sk->sk_kern_sock)
3394 lockdep_set_class_and_name(
3395 &sk->sk_callback_lock,
3396 af_kern_callback_keys + sk->sk_family,
3397 af_family_kern_clock_key_strings[sk->sk_family]);
3399 lockdep_set_class_and_name(
3400 &sk->sk_callback_lock,
3401 af_callback_keys + sk->sk_family,
3402 af_family_clock_key_strings[sk->sk_family]);
3404 sk->sk_state_change = sock_def_wakeup;
3405 sk->sk_data_ready = sock_def_readable;
3406 sk->sk_write_space = sock_def_write_space;
3407 sk->sk_error_report = sock_def_error_report;
3408 sk->sk_destruct = sock_def_destruct;
3410 sk->sk_frag.page = NULL;
3411 sk->sk_frag.offset = 0;
3412 sk->sk_peek_off = -1;
3414 sk->sk_peer_pid = NULL;
3415 sk->sk_peer_cred = NULL;
3416 spin_lock_init(&sk->sk_peer_lock);
3418 sk->sk_write_pending = 0;
3419 sk->sk_rcvlowat = 1;
3420 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3421 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3423 sk->sk_stamp = SK_DEFAULT_STAMP;
3424 #if BITS_PER_LONG==32
3425 seqlock_init(&sk->sk_stamp_seq);
3427 atomic_set(&sk->sk_zckey, 0);
3429 #ifdef CONFIG_NET_RX_BUSY_POLL
3431 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read);
3434 sk->sk_max_pacing_rate = ~0UL;
3435 sk->sk_pacing_rate = ~0UL;
3436 WRITE_ONCE(sk->sk_pacing_shift, 10);
3437 sk->sk_incoming_cpu = -1;
3439 sk_rx_queue_clear(sk);
3441 * Before updating sk_refcnt, we must commit prior changes to memory
3442 * (Documentation/RCU/rculist_nulls.rst for details)
3445 refcount_set(&sk->sk_refcnt, 1);
3446 atomic_set(&sk->sk_drops, 0);
3448 EXPORT_SYMBOL(sock_init_data_uid);
3450 void sock_init_data(struct socket *sock, struct sock *sk)
3453 SOCK_INODE(sock)->i_uid :
3454 make_kuid(sock_net(sk)->user_ns, 0);
3456 sock_init_data_uid(sock, sk, uid);
3458 EXPORT_SYMBOL(sock_init_data);
3460 void lock_sock_nested(struct sock *sk, int subclass)
3462 /* The sk_lock has mutex_lock() semantics here. */
3463 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3466 spin_lock_bh(&sk->sk_lock.slock);
3467 if (sock_owned_by_user_nocheck(sk))
3469 sk->sk_lock.owned = 1;
3470 spin_unlock_bh(&sk->sk_lock.slock);
3472 EXPORT_SYMBOL(lock_sock_nested);
3474 void release_sock(struct sock *sk)
3476 spin_lock_bh(&sk->sk_lock.slock);
3477 if (sk->sk_backlog.tail)
3480 /* Warning : release_cb() might need to release sk ownership,
3481 * ie call sock_release_ownership(sk) before us.
3483 if (sk->sk_prot->release_cb)
3484 sk->sk_prot->release_cb(sk);
3486 sock_release_ownership(sk);
3487 if (waitqueue_active(&sk->sk_lock.wq))
3488 wake_up(&sk->sk_lock.wq);
3489 spin_unlock_bh(&sk->sk_lock.slock);
3491 EXPORT_SYMBOL(release_sock);
3493 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3496 spin_lock_bh(&sk->sk_lock.slock);
3498 if (!sock_owned_by_user_nocheck(sk)) {
3500 * Fast path return with bottom halves disabled and
3501 * sock::sk_lock.slock held.
3503 * The 'mutex' is not contended and holding
3504 * sock::sk_lock.slock prevents all other lockers to
3505 * proceed so the corresponding unlock_sock_fast() can
3506 * avoid the slow path of release_sock() completely and
3507 * just release slock.
3509 * From a semantical POV this is equivalent to 'acquiring'
3510 * the 'mutex', hence the corresponding lockdep
3511 * mutex_release() has to happen in the fast path of
3512 * unlock_sock_fast().
3518 sk->sk_lock.owned = 1;
3519 __acquire(&sk->sk_lock.slock);
3520 spin_unlock_bh(&sk->sk_lock.slock);
3523 EXPORT_SYMBOL(__lock_sock_fast);
3525 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3526 bool timeval, bool time32)
3528 struct sock *sk = sock->sk;
3529 struct timespec64 ts;
3531 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3532 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3533 if (ts.tv_sec == -1)
3535 if (ts.tv_sec == 0) {
3536 ktime_t kt = ktime_get_real();
3537 sock_write_timestamp(sk, kt);
3538 ts = ktime_to_timespec64(kt);
3544 #ifdef CONFIG_COMPAT_32BIT_TIME
3546 return put_old_timespec32(&ts, userstamp);
3548 #ifdef CONFIG_SPARC64
3549 /* beware of padding in sparc64 timeval */
3550 if (timeval && !in_compat_syscall()) {
3551 struct __kernel_old_timeval __user tv = {
3552 .tv_sec = ts.tv_sec,
3553 .tv_usec = ts.tv_nsec,
3555 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3560 return put_timespec64(&ts, userstamp);
3562 EXPORT_SYMBOL(sock_gettstamp);
3564 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3566 if (!sock_flag(sk, flag)) {
3567 unsigned long previous_flags = sk->sk_flags;
3569 sock_set_flag(sk, flag);
3571 * we just set one of the two flags which require net
3572 * time stamping, but time stamping might have been on
3573 * already because of the other one
3575 if (sock_needs_netstamp(sk) &&
3576 !(previous_flags & SK_FLAGS_TIMESTAMP))
3577 net_enable_timestamp();
3581 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3582 int level, int type)
3584 struct sock_exterr_skb *serr;
3585 struct sk_buff *skb;
3589 skb = sock_dequeue_err_skb(sk);
3595 msg->msg_flags |= MSG_TRUNC;
3598 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3602 sock_recv_timestamp(msg, sk, skb);
3604 serr = SKB_EXT_ERR(skb);
3605 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3607 msg->msg_flags |= MSG_ERRQUEUE;
3615 EXPORT_SYMBOL(sock_recv_errqueue);
3618 * Get a socket option on an socket.
3620 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3621 * asynchronous errors should be reported by getsockopt. We assume
3622 * this means if you specify SO_ERROR (otherwise whats the point of it).
3624 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3625 char __user *optval, int __user *optlen)
3627 struct sock *sk = sock->sk;
3629 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3630 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3632 EXPORT_SYMBOL(sock_common_getsockopt);
3634 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3637 struct sock *sk = sock->sk;
3641 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3643 msg->msg_namelen = addr_len;
3646 EXPORT_SYMBOL(sock_common_recvmsg);
3649 * Set socket options on an inet socket.
3651 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3652 sockptr_t optval, unsigned int optlen)
3654 struct sock *sk = sock->sk;
3656 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3657 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3659 EXPORT_SYMBOL(sock_common_setsockopt);
3661 void sk_common_release(struct sock *sk)
3663 if (sk->sk_prot->destroy)
3664 sk->sk_prot->destroy(sk);
3667 * Observation: when sk_common_release is called, processes have
3668 * no access to socket. But net still has.
3669 * Step one, detach it from networking:
3671 * A. Remove from hash tables.
3674 sk->sk_prot->unhash(sk);
3677 * In this point socket cannot receive new packets, but it is possible
3678 * that some packets are in flight because some CPU runs receiver and
3679 * did hash table lookup before we unhashed socket. They will achieve
3680 * receive queue and will be purged by socket destructor.
3682 * Also we still have packets pending on receive queue and probably,
3683 * our own packets waiting in device queues. sock_destroy will drain
3684 * receive queue, but transmitted packets will delay socket destruction
3685 * until the last reference will be released.
3690 xfrm_sk_free_policy(sk);
3692 sk_refcnt_debug_release(sk);
3696 EXPORT_SYMBOL(sk_common_release);
3698 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3700 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3702 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3703 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3704 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3705 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3706 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3707 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3708 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3709 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3710 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3713 #ifdef CONFIG_PROC_FS
3714 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3716 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3718 int cpu, idx = prot->inuse_idx;
3721 for_each_possible_cpu(cpu)
3722 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3724 return res >= 0 ? res : 0;
3726 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3728 int sock_inuse_get(struct net *net)
3732 for_each_possible_cpu(cpu)
3733 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3738 EXPORT_SYMBOL_GPL(sock_inuse_get);
3740 static int __net_init sock_inuse_init_net(struct net *net)
3742 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3743 if (net->core.prot_inuse == NULL)
3748 static void __net_exit sock_inuse_exit_net(struct net *net)
3750 free_percpu(net->core.prot_inuse);
3753 static struct pernet_operations net_inuse_ops = {
3754 .init = sock_inuse_init_net,
3755 .exit = sock_inuse_exit_net,
3758 static __init int net_inuse_init(void)
3760 if (register_pernet_subsys(&net_inuse_ops))
3761 panic("Cannot initialize net inuse counters");
3766 core_initcall(net_inuse_init);
3768 static int assign_proto_idx(struct proto *prot)
3770 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3772 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3773 pr_err("PROTO_INUSE_NR exhausted\n");
3777 set_bit(prot->inuse_idx, proto_inuse_idx);
3781 static void release_proto_idx(struct proto *prot)
3783 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3784 clear_bit(prot->inuse_idx, proto_inuse_idx);
3787 static inline int assign_proto_idx(struct proto *prot)
3792 static inline void release_proto_idx(struct proto *prot)
3798 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3802 kfree(twsk_prot->twsk_slab_name);
3803 twsk_prot->twsk_slab_name = NULL;
3804 kmem_cache_destroy(twsk_prot->twsk_slab);
3805 twsk_prot->twsk_slab = NULL;
3808 static int tw_prot_init(const struct proto *prot)
3810 struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3815 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3817 if (!twsk_prot->twsk_slab_name)
3820 twsk_prot->twsk_slab =
3821 kmem_cache_create(twsk_prot->twsk_slab_name,
3822 twsk_prot->twsk_obj_size, 0,
3823 SLAB_ACCOUNT | prot->slab_flags,
3825 if (!twsk_prot->twsk_slab) {
3826 pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3834 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3838 kfree(rsk_prot->slab_name);
3839 rsk_prot->slab_name = NULL;
3840 kmem_cache_destroy(rsk_prot->slab);
3841 rsk_prot->slab = NULL;
3844 static int req_prot_init(const struct proto *prot)
3846 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3851 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3853 if (!rsk_prot->slab_name)
3856 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3857 rsk_prot->obj_size, 0,
3858 SLAB_ACCOUNT | prot->slab_flags,
3861 if (!rsk_prot->slab) {
3862 pr_crit("%s: Can't create request sock SLAB cache!\n",
3869 int proto_register(struct proto *prot, int alloc_slab)
3873 if (prot->memory_allocated && !prot->sysctl_mem) {
3874 pr_err("%s: missing sysctl_mem\n", prot->name);
3877 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3878 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3882 prot->slab = kmem_cache_create_usercopy(prot->name,
3884 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3886 prot->useroffset, prot->usersize,
3889 if (prot->slab == NULL) {
3890 pr_crit("%s: Can't create sock SLAB cache!\n",
3895 if (req_prot_init(prot))
3896 goto out_free_request_sock_slab;
3898 if (tw_prot_init(prot))
3899 goto out_free_timewait_sock_slab;
3902 mutex_lock(&proto_list_mutex);
3903 ret = assign_proto_idx(prot);
3905 mutex_unlock(&proto_list_mutex);
3906 goto out_free_timewait_sock_slab;
3908 list_add(&prot->node, &proto_list);
3909 mutex_unlock(&proto_list_mutex);
3912 out_free_timewait_sock_slab:
3914 tw_prot_cleanup(prot->twsk_prot);
3915 out_free_request_sock_slab:
3917 req_prot_cleanup(prot->rsk_prot);
3919 kmem_cache_destroy(prot->slab);
3925 EXPORT_SYMBOL(proto_register);
3927 void proto_unregister(struct proto *prot)
3929 mutex_lock(&proto_list_mutex);
3930 release_proto_idx(prot);
3931 list_del(&prot->node);
3932 mutex_unlock(&proto_list_mutex);
3934 kmem_cache_destroy(prot->slab);
3937 req_prot_cleanup(prot->rsk_prot);
3938 tw_prot_cleanup(prot->twsk_prot);
3940 EXPORT_SYMBOL(proto_unregister);
3942 int sock_load_diag_module(int family, int protocol)
3945 if (!sock_is_registered(family))
3948 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3949 NETLINK_SOCK_DIAG, family);
3953 if (family == AF_INET &&
3954 protocol != IPPROTO_RAW &&
3955 protocol < MAX_INET_PROTOS &&
3956 !rcu_access_pointer(inet_protos[protocol]))
3960 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3961 NETLINK_SOCK_DIAG, family, protocol);
3963 EXPORT_SYMBOL(sock_load_diag_module);
3965 #ifdef CONFIG_PROC_FS
3966 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3967 __acquires(proto_list_mutex)
3969 mutex_lock(&proto_list_mutex);
3970 return seq_list_start_head(&proto_list, *pos);
3973 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3975 return seq_list_next(v, &proto_list, pos);
3978 static void proto_seq_stop(struct seq_file *seq, void *v)
3979 __releases(proto_list_mutex)
3981 mutex_unlock(&proto_list_mutex);
3984 static char proto_method_implemented(const void *method)
3986 return method == NULL ? 'n' : 'y';
3988 static long sock_prot_memory_allocated(struct proto *proto)
3990 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3993 static const char *sock_prot_memory_pressure(struct proto *proto)
3995 return proto->memory_pressure != NULL ?
3996 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3999 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4002 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
4003 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4006 sock_prot_inuse_get(seq_file_net(seq), proto),
4007 sock_prot_memory_allocated(proto),
4008 sock_prot_memory_pressure(proto),
4010 proto->slab == NULL ? "no" : "yes",
4011 module_name(proto->owner),
4012 proto_method_implemented(proto->close),
4013 proto_method_implemented(proto->connect),
4014 proto_method_implemented(proto->disconnect),
4015 proto_method_implemented(proto->accept),
4016 proto_method_implemented(proto->ioctl),
4017 proto_method_implemented(proto->init),
4018 proto_method_implemented(proto->destroy),
4019 proto_method_implemented(proto->shutdown),
4020 proto_method_implemented(proto->setsockopt),
4021 proto_method_implemented(proto->getsockopt),
4022 proto_method_implemented(proto->sendmsg),
4023 proto_method_implemented(proto->recvmsg),
4024 proto_method_implemented(proto->sendpage),
4025 proto_method_implemented(proto->bind),
4026 proto_method_implemented(proto->backlog_rcv),
4027 proto_method_implemented(proto->hash),
4028 proto_method_implemented(proto->unhash),
4029 proto_method_implemented(proto->get_port),
4030 proto_method_implemented(proto->enter_memory_pressure));
4033 static int proto_seq_show(struct seq_file *seq, void *v)
4035 if (v == &proto_list)
4036 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4045 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4047 proto_seq_printf(seq, list_entry(v, struct proto, node));
4051 static const struct seq_operations proto_seq_ops = {
4052 .start = proto_seq_start,
4053 .next = proto_seq_next,
4054 .stop = proto_seq_stop,
4055 .show = proto_seq_show,
4058 static __net_init int proto_init_net(struct net *net)
4060 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4061 sizeof(struct seq_net_private)))
4067 static __net_exit void proto_exit_net(struct net *net)
4069 remove_proc_entry("protocols", net->proc_net);
4073 static __net_initdata struct pernet_operations proto_net_ops = {
4074 .init = proto_init_net,
4075 .exit = proto_exit_net,
4078 static int __init proto_init(void)
4080 return register_pernet_subsys(&proto_net_ops);
4083 subsys_initcall(proto_init);
4085 #endif /* PROC_FS */
4087 #ifdef CONFIG_NET_RX_BUSY_POLL
4088 bool sk_busy_loop_end(void *p, unsigned long start_time)
4090 struct sock *sk = p;
4092 return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4093 sk_busy_loop_timeout(sk, start_time);
4095 EXPORT_SYMBOL(sk_busy_loop_end);
4096 #endif /* CONFIG_NET_RX_BUSY_POLL */
4098 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4100 if (!sk->sk_prot->bind_add)
4102 return sk->sk_prot->bind_add(sk, addr, addr_len);
4104 EXPORT_SYMBOL(sock_bind_add);