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/udp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 #include <linux/static_key.h>
115 #include <linux/memcontrol.h>
116 #include <linux/prefetch.h>
117 #include <linux/compat.h>
118 #include <linux/mroute.h>
119 #include <linux/mroute6.h>
120 #include <linux/icmpv6.h>
122 #include <linux/uaccess.h>
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <net/net_namespace.h>
128 #include <net/request_sock.h>
129 #include <net/sock.h>
130 #include <linux/net_tstamp.h>
131 #include <net/xfrm.h>
132 #include <linux/ipsec.h>
133 #include <net/cls_cgroup.h>
134 #include <net/netprio_cgroup.h>
135 #include <linux/sock_diag.h>
137 #include <linux/filter.h>
138 #include <net/sock_reuseport.h>
139 #include <net/bpf_sk_storage.h>
141 #include <trace/events/sock.h>
144 #include <net/busy_poll.h>
145 #include <net/phonet/phonet.h>
147 #include <linux/ethtool.h>
151 static DEFINE_MUTEX(proto_list_mutex);
152 static LIST_HEAD(proto_list);
154 static void sock_def_write_space_wfree(struct sock *sk);
155 static void sock_def_write_space(struct sock *sk);
158 * sk_ns_capable - General socket capability test
159 * @sk: Socket to use a capability on or through
160 * @user_ns: The user namespace of the capability to use
161 * @cap: The capability to use
163 * Test to see if the opener of the socket had when the socket was
164 * created and the current process has the capability @cap in the user
165 * namespace @user_ns.
167 bool sk_ns_capable(const struct sock *sk,
168 struct user_namespace *user_ns, int cap)
170 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
171 ns_capable(user_ns, cap);
173 EXPORT_SYMBOL(sk_ns_capable);
176 * sk_capable - Socket global capability test
177 * @sk: Socket to use a capability on or through
178 * @cap: The global capability to use
180 * Test to see if the opener of the socket had when the socket was
181 * created and the current process has the capability @cap in all user
184 bool sk_capable(const struct sock *sk, int cap)
186 return sk_ns_capable(sk, &init_user_ns, cap);
188 EXPORT_SYMBOL(sk_capable);
191 * sk_net_capable - Network namespace socket capability test
192 * @sk: Socket to use a capability on or through
193 * @cap: The capability to use
195 * Test to see if the opener of the socket had when the socket was created
196 * and the current process has the capability @cap over the network namespace
197 * the socket is a member of.
199 bool sk_net_capable(const struct sock *sk, int cap)
201 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
203 EXPORT_SYMBOL(sk_net_capable);
206 * Each address family might have different locking rules, so we have
207 * one slock key per address family and separate keys for internal and
210 static struct lock_class_key af_family_keys[AF_MAX];
211 static struct lock_class_key af_family_kern_keys[AF_MAX];
212 static struct lock_class_key af_family_slock_keys[AF_MAX];
213 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
216 * Make lock validator output more readable. (we pre-construct these
217 * strings build-time, so that runtime initialization of socket
221 #define _sock_locks(x) \
222 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
223 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
224 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
225 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
226 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
227 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
228 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
229 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
230 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
231 x "27" , x "28" , x "AF_CAN" , \
232 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
233 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
234 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
235 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
236 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
240 static const char *const af_family_key_strings[AF_MAX+1] = {
241 _sock_locks("sk_lock-")
243 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
244 _sock_locks("slock-")
246 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
247 _sock_locks("clock-")
250 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
251 _sock_locks("k-sk_lock-")
253 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
254 _sock_locks("k-slock-")
256 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
257 _sock_locks("k-clock-")
259 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
260 _sock_locks("rlock-")
262 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
263 _sock_locks("wlock-")
265 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
266 _sock_locks("elock-")
270 * sk_callback_lock and sk queues locking rules are per-address-family,
271 * so split the lock classes by using a per-AF key:
273 static struct lock_class_key af_callback_keys[AF_MAX];
274 static struct lock_class_key af_rlock_keys[AF_MAX];
275 static struct lock_class_key af_wlock_keys[AF_MAX];
276 static struct lock_class_key af_elock_keys[AF_MAX];
277 static struct lock_class_key af_kern_callback_keys[AF_MAX];
279 /* Run time adjustable parameters. */
280 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
281 EXPORT_SYMBOL(sysctl_wmem_max);
282 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
283 EXPORT_SYMBOL(sysctl_rmem_max);
284 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
285 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
286 int sysctl_mem_pcpu_rsv __read_mostly = SK_MEMORY_PCPU_RESERVE;
288 int sysctl_tstamp_allow_data __read_mostly = 1;
290 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
291 EXPORT_SYMBOL_GPL(memalloc_socks_key);
294 * sk_set_memalloc - sets %SOCK_MEMALLOC
295 * @sk: socket to set it on
297 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
298 * It's the responsibility of the admin to adjust min_free_kbytes
299 * to meet the requirements
301 void sk_set_memalloc(struct sock *sk)
303 sock_set_flag(sk, SOCK_MEMALLOC);
304 sk->sk_allocation |= __GFP_MEMALLOC;
305 static_branch_inc(&memalloc_socks_key);
307 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309 void sk_clear_memalloc(struct sock *sk)
311 sock_reset_flag(sk, SOCK_MEMALLOC);
312 sk->sk_allocation &= ~__GFP_MEMALLOC;
313 static_branch_dec(&memalloc_socks_key);
316 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
317 * progress of swapping. SOCK_MEMALLOC may be cleared while
318 * it has rmem allocations due to the last swapfile being deactivated
319 * but there is a risk that the socket is unusable due to exceeding
320 * the rmem limits. Reclaim the reserves and obey rmem limits again.
324 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
329 unsigned int noreclaim_flag;
331 /* these should have been dropped before queueing */
332 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334 noreclaim_flag = memalloc_noreclaim_save();
335 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
339 memalloc_noreclaim_restore(noreclaim_flag);
343 EXPORT_SYMBOL(__sk_backlog_rcv);
345 void sk_error_report(struct sock *sk)
347 sk->sk_error_report(sk);
349 switch (sk->sk_family) {
353 trace_inet_sk_error_report(sk);
359 EXPORT_SYMBOL(sk_error_report);
361 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 struct __kernel_sock_timeval tv;
365 if (timeo == MAX_SCHEDULE_TIMEOUT) {
369 tv.tv_sec = timeo / HZ;
370 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
373 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
374 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
375 *(struct old_timeval32 *)optval = tv32;
380 struct __kernel_old_timeval old_tv;
381 old_tv.tv_sec = tv.tv_sec;
382 old_tv.tv_usec = tv.tv_usec;
383 *(struct __kernel_old_timeval *)optval = old_tv;
384 return sizeof(old_tv);
387 *(struct __kernel_sock_timeval *)optval = tv;
390 EXPORT_SYMBOL(sock_get_timeout);
392 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
393 sockptr_t optval, int optlen, bool old_timeval)
395 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
396 struct old_timeval32 tv32;
398 if (optlen < sizeof(tv32))
401 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 tv->tv_sec = tv32.tv_sec;
404 tv->tv_usec = tv32.tv_usec;
405 } else if (old_timeval) {
406 struct __kernel_old_timeval old_tv;
408 if (optlen < sizeof(old_tv))
410 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 tv->tv_sec = old_tv.tv_sec;
413 tv->tv_usec = old_tv.tv_usec;
415 if (optlen < sizeof(*tv))
417 if (copy_from_sockptr(tv, optval, sizeof(*tv)))
423 EXPORT_SYMBOL(sock_copy_user_timeval);
425 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
428 struct __kernel_sock_timeval tv;
429 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
435 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
439 static int warned __read_mostly;
441 WRITE_ONCE(*timeo_p, 0);
442 if (warned < 10 && net_ratelimit()) {
444 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
445 __func__, current->comm, task_pid_nr(current));
449 val = MAX_SCHEDULE_TIMEOUT;
450 if ((tv.tv_sec || tv.tv_usec) &&
451 (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
452 val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 WRITE_ONCE(*timeo_p, val);
458 static bool sock_needs_netstamp(const struct sock *sk)
460 switch (sk->sk_family) {
469 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
471 if (sk->sk_flags & flags) {
472 sk->sk_flags &= ~flags;
473 if (sock_needs_netstamp(sk) &&
474 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
475 net_disable_timestamp();
480 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
483 struct sk_buff_head *list = &sk->sk_receive_queue;
485 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
486 atomic_inc(&sk->sk_drops);
487 trace_sock_rcvqueue_full(sk, skb);
491 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
492 atomic_inc(&sk->sk_drops);
497 skb_set_owner_r(skb, sk);
499 /* we escape from rcu protected region, make sure we dont leak
504 spin_lock_irqsave(&list->lock, flags);
505 sock_skb_set_dropcount(sk, skb);
506 __skb_queue_tail(list, skb);
507 spin_unlock_irqrestore(&list->lock, flags);
509 if (!sock_flag(sk, SOCK_DEAD))
510 sk->sk_data_ready(sk);
513 EXPORT_SYMBOL(__sock_queue_rcv_skb);
515 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
516 enum skb_drop_reason *reason)
518 enum skb_drop_reason drop_reason;
521 err = sk_filter(sk, skb);
523 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
526 err = __sock_queue_rcv_skb(sk, skb);
529 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
532 drop_reason = SKB_DROP_REASON_PROTO_MEM;
535 drop_reason = SKB_NOT_DROPPED_YET;
540 *reason = drop_reason;
543 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
545 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
546 const int nested, unsigned int trim_cap, bool refcounted)
548 int rc = NET_RX_SUCCESS;
550 if (sk_filter_trim_cap(sk, skb, trim_cap))
551 goto discard_and_relse;
555 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
556 atomic_inc(&sk->sk_drops);
557 goto discard_and_relse;
560 bh_lock_sock_nested(sk);
563 if (!sock_owned_by_user(sk)) {
565 * trylock + unlock semantics:
567 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
569 rc = sk_backlog_rcv(sk, skb);
571 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
572 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
574 atomic_inc(&sk->sk_drops);
575 goto discard_and_relse;
587 EXPORT_SYMBOL(__sk_receive_skb);
589 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
591 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
593 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
595 struct dst_entry *dst = __sk_dst_get(sk);
597 if (dst && dst->obsolete &&
598 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
599 dst, cookie) == NULL) {
600 sk_tx_queue_clear(sk);
601 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
602 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
609 EXPORT_SYMBOL(__sk_dst_check);
611 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
613 struct dst_entry *dst = sk_dst_get(sk);
615 if (dst && dst->obsolete &&
616 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
617 dst, cookie) == NULL) {
625 EXPORT_SYMBOL(sk_dst_check);
627 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
629 int ret = -ENOPROTOOPT;
630 #ifdef CONFIG_NETDEVICES
631 struct net *net = sock_net(sk);
635 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
642 /* Paired with all READ_ONCE() done locklessly. */
643 WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
645 if (sk->sk_prot->rehash)
646 sk->sk_prot->rehash(sk);
657 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
663 ret = sock_bindtoindex_locked(sk, ifindex);
669 EXPORT_SYMBOL(sock_bindtoindex);
671 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
673 int ret = -ENOPROTOOPT;
674 #ifdef CONFIG_NETDEVICES
675 struct net *net = sock_net(sk);
676 char devname[IFNAMSIZ];
683 /* Bind this socket to a particular device like "eth0",
684 * as specified in the passed interface name. If the
685 * name is "" or the option length is zero the socket
688 if (optlen > IFNAMSIZ - 1)
689 optlen = IFNAMSIZ - 1;
690 memset(devname, 0, sizeof(devname));
693 if (copy_from_sockptr(devname, optval, optlen))
697 if (devname[0] != '\0') {
698 struct net_device *dev;
701 dev = dev_get_by_name_rcu(net, devname);
703 index = dev->ifindex;
710 sockopt_lock_sock(sk);
711 ret = sock_bindtoindex_locked(sk, index);
712 sockopt_release_sock(sk);
719 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
720 sockptr_t optlen, int len)
722 int ret = -ENOPROTOOPT;
723 #ifdef CONFIG_NETDEVICES
724 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
725 struct net *net = sock_net(sk);
726 char devname[IFNAMSIZ];
728 if (bound_dev_if == 0) {
737 ret = netdev_get_name(net, devname, bound_dev_if);
741 len = strlen(devname) + 1;
744 if (copy_to_sockptr(optval, devname, len))
749 if (copy_to_sockptr(optlen, &len, sizeof(int)))
760 bool sk_mc_loop(const struct sock *sk)
762 if (dev_recursion_level())
766 /* IPV6_ADDRFORM can change sk->sk_family under us. */
767 switch (READ_ONCE(sk->sk_family)) {
769 return inet_test_bit(MC_LOOP, sk);
770 #if IS_ENABLED(CONFIG_IPV6)
772 return inet6_test_bit(MC6_LOOP, sk);
778 EXPORT_SYMBOL(sk_mc_loop);
780 void sock_set_reuseaddr(struct sock *sk)
783 sk->sk_reuse = SK_CAN_REUSE;
786 EXPORT_SYMBOL(sock_set_reuseaddr);
788 void sock_set_reuseport(struct sock *sk)
791 sk->sk_reuseport = true;
794 EXPORT_SYMBOL(sock_set_reuseport);
796 void sock_no_linger(struct sock *sk)
799 WRITE_ONCE(sk->sk_lingertime, 0);
800 sock_set_flag(sk, SOCK_LINGER);
803 EXPORT_SYMBOL(sock_no_linger);
805 void sock_set_priority(struct sock *sk, u32 priority)
807 WRITE_ONCE(sk->sk_priority, priority);
809 EXPORT_SYMBOL(sock_set_priority);
811 void sock_set_sndtimeo(struct sock *sk, s64 secs)
814 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
815 WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
817 WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
820 EXPORT_SYMBOL(sock_set_sndtimeo);
822 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
825 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
826 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
827 sock_set_flag(sk, SOCK_RCVTSTAMP);
828 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
830 sock_reset_flag(sk, SOCK_RCVTSTAMP);
831 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
835 void sock_enable_timestamps(struct sock *sk)
838 __sock_set_timestamps(sk, true, false, true);
841 EXPORT_SYMBOL(sock_enable_timestamps);
843 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
846 case SO_TIMESTAMP_OLD:
847 __sock_set_timestamps(sk, valbool, false, false);
849 case SO_TIMESTAMP_NEW:
850 __sock_set_timestamps(sk, valbool, true, false);
852 case SO_TIMESTAMPNS_OLD:
853 __sock_set_timestamps(sk, valbool, false, true);
855 case SO_TIMESTAMPNS_NEW:
856 __sock_set_timestamps(sk, valbool, true, true);
861 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
863 struct net *net = sock_net(sk);
864 struct net_device *dev = NULL;
869 if (sk->sk_bound_dev_if)
870 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
873 pr_err("%s: sock not bind to device\n", __func__);
877 num = ethtool_get_phc_vclocks(dev, &vclock_index);
880 for (i = 0; i < num; i++) {
881 if (*(vclock_index + i) == phc_index) {
893 WRITE_ONCE(sk->sk_bind_phc, phc_index);
898 int sock_set_timestamping(struct sock *sk, int optname,
899 struct so_timestamping timestamping)
901 int val = timestamping.flags;
904 if (val & ~SOF_TIMESTAMPING_MASK)
907 if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
908 !(val & SOF_TIMESTAMPING_OPT_ID))
911 if (val & SOF_TIMESTAMPING_OPT_ID &&
912 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
914 if ((1 << sk->sk_state) &
915 (TCPF_CLOSE | TCPF_LISTEN))
917 if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
918 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
920 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
922 atomic_set(&sk->sk_tskey, 0);
926 if (val & SOF_TIMESTAMPING_OPT_STATS &&
927 !(val & SOF_TIMESTAMPING_OPT_TSONLY))
930 if (val & SOF_TIMESTAMPING_BIND_PHC) {
931 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
936 WRITE_ONCE(sk->sk_tsflags, val);
937 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
939 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
940 sock_enable_timestamp(sk,
941 SOCK_TIMESTAMPING_RX_SOFTWARE);
943 sock_disable_timestamp(sk,
944 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
948 void sock_set_keepalive(struct sock *sk)
951 if (sk->sk_prot->keepalive)
952 sk->sk_prot->keepalive(sk, true);
953 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
956 EXPORT_SYMBOL(sock_set_keepalive);
958 static void __sock_set_rcvbuf(struct sock *sk, int val)
960 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
961 * as a negative value.
963 val = min_t(int, val, INT_MAX / 2);
964 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
966 /* We double it on the way in to account for "struct sk_buff" etc.
967 * overhead. Applications assume that the SO_RCVBUF setting they make
968 * will allow that much actual data to be received on that socket.
970 * Applications are unaware that "struct sk_buff" and other overheads
971 * allocate from the receive buffer during socket buffer allocation.
973 * And after considering the possible alternatives, returning the value
974 * we actually used in getsockopt is the most desirable behavior.
976 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
979 void sock_set_rcvbuf(struct sock *sk, int val)
982 __sock_set_rcvbuf(sk, val);
985 EXPORT_SYMBOL(sock_set_rcvbuf);
987 static void __sock_set_mark(struct sock *sk, u32 val)
989 if (val != sk->sk_mark) {
990 WRITE_ONCE(sk->sk_mark, val);
995 void sock_set_mark(struct sock *sk, u32 val)
998 __sock_set_mark(sk, val);
1001 EXPORT_SYMBOL(sock_set_mark);
1003 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1005 /* Round down bytes to multiple of pages */
1006 bytes = round_down(bytes, PAGE_SIZE);
1008 WARN_ON(bytes > sk->sk_reserved_mem);
1009 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1013 static int sock_reserve_memory(struct sock *sk, int bytes)
1019 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1025 pages = sk_mem_pages(bytes);
1027 /* pre-charge to memcg */
1028 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1029 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1033 /* pre-charge to forward_alloc */
1034 sk_memory_allocated_add(sk, pages);
1035 allocated = sk_memory_allocated(sk);
1036 /* If the system goes into memory pressure with this
1037 * precharge, give up and return error.
1039 if (allocated > sk_prot_mem_limits(sk, 1)) {
1040 sk_memory_allocated_sub(sk, pages);
1041 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1044 sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1046 WRITE_ONCE(sk->sk_reserved_mem,
1047 sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1052 void sockopt_lock_sock(struct sock *sk)
1054 /* When current->bpf_ctx is set, the setsockopt is called from
1055 * a bpf prog. bpf has ensured the sk lock has been
1056 * acquired before calling setsockopt().
1058 if (has_current_bpf_ctx())
1063 EXPORT_SYMBOL(sockopt_lock_sock);
1065 void sockopt_release_sock(struct sock *sk)
1067 if (has_current_bpf_ctx())
1072 EXPORT_SYMBOL(sockopt_release_sock);
1074 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1076 return has_current_bpf_ctx() || ns_capable(ns, cap);
1078 EXPORT_SYMBOL(sockopt_ns_capable);
1080 bool sockopt_capable(int cap)
1082 return has_current_bpf_ctx() || capable(cap);
1084 EXPORT_SYMBOL(sockopt_capable);
1087 * This is meant for all protocols to use and covers goings on
1088 * at the socket level. Everything here is generic.
1091 int sk_setsockopt(struct sock *sk, int level, int optname,
1092 sockptr_t optval, unsigned int optlen)
1094 struct so_timestamping timestamping;
1095 struct socket *sock = sk->sk_socket;
1096 struct sock_txtime sk_txtime;
1103 * Options without arguments
1106 if (optname == SO_BINDTODEVICE)
1107 return sock_setbindtodevice(sk, optval, optlen);
1109 if (optlen < sizeof(int))
1112 if (copy_from_sockptr(&val, optval, sizeof(val)))
1115 valbool = val ? 1 : 0;
1117 /* handle options which do not require locking the socket. */
1120 if ((val >= 0 && val <= 6) ||
1121 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1122 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1123 sock_set_priority(sk, val);
1128 assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1131 assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1134 assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1140 return -ENOPROTOOPT;
1141 #ifdef CONFIG_NET_RX_BUSY_POLL
1145 WRITE_ONCE(sk->sk_ll_usec, val);
1147 case SO_PREFER_BUSY_POLL:
1148 if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1150 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1152 case SO_BUSY_POLL_BUDGET:
1153 if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1154 !sockopt_capable(CAP_NET_ADMIN))
1156 if (val < 0 || val > U16_MAX)
1158 WRITE_ONCE(sk->sk_busy_poll_budget, val);
1161 case SO_MAX_PACING_RATE:
1163 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1164 unsigned long pacing_rate;
1166 if (sizeof(ulval) != sizeof(val) &&
1167 optlen >= sizeof(ulval) &&
1168 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1172 cmpxchg(&sk->sk_pacing_status,
1175 /* Pairs with READ_ONCE() from sk_getsockopt() */
1176 WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1177 pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1178 if (ulval < pacing_rate)
1179 WRITE_ONCE(sk->sk_pacing_rate, ulval);
1183 if (val < -1 || val > 1)
1185 if ((u8)val == SOCK_TXREHASH_DEFAULT)
1186 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1187 /* Paired with READ_ONCE() in tcp_rtx_synack()
1188 * and sk_getsockopt().
1190 WRITE_ONCE(sk->sk_txrehash, (u8)val);
1194 int (*set_peek_off)(struct sock *sk, int val);
1196 set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1198 ret = set_peek_off(sk, val);
1205 sockopt_lock_sock(sk);
1209 if (val && !sockopt_capable(CAP_NET_ADMIN))
1212 sock_valbool_flag(sk, SOCK_DBG, valbool);
1215 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1218 sk->sk_reuseport = valbool;
1221 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1225 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1228 /* Don't error on this BSD doesn't and if you think
1229 * about it this is right. Otherwise apps have to
1230 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1231 * are treated in BSD as hints
1233 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1235 /* Ensure val * 2 fits into an int, to prevent max_t()
1236 * from treating it as a negative value.
1238 val = min_t(int, val, INT_MAX / 2);
1239 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1240 WRITE_ONCE(sk->sk_sndbuf,
1241 max_t(int, val * 2, SOCK_MIN_SNDBUF));
1242 /* Wake up sending tasks if we upped the value. */
1243 sk->sk_write_space(sk);
1246 case SO_SNDBUFFORCE:
1247 if (!sockopt_capable(CAP_NET_ADMIN)) {
1252 /* No negative values (to prevent underflow, as val will be
1260 /* Don't error on this BSD doesn't and if you think
1261 * about it this is right. Otherwise apps have to
1262 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1263 * are treated in BSD as hints
1265 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1268 case SO_RCVBUFFORCE:
1269 if (!sockopt_capable(CAP_NET_ADMIN)) {
1274 /* No negative values (to prevent underflow, as val will be
1277 __sock_set_rcvbuf(sk, max(val, 0));
1281 if (sk->sk_prot->keepalive)
1282 sk->sk_prot->keepalive(sk, valbool);
1283 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1287 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1291 sk->sk_no_check_tx = valbool;
1295 if (optlen < sizeof(ling)) {
1296 ret = -EINVAL; /* 1003.1g */
1299 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1303 if (!ling.l_onoff) {
1304 sock_reset_flag(sk, SOCK_LINGER);
1306 unsigned long t_sec = ling.l_linger;
1308 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1309 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1311 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1312 sock_set_flag(sk, SOCK_LINGER);
1319 case SO_TIMESTAMP_OLD:
1320 case SO_TIMESTAMP_NEW:
1321 case SO_TIMESTAMPNS_OLD:
1322 case SO_TIMESTAMPNS_NEW:
1323 sock_set_timestamp(sk, optname, valbool);
1326 case SO_TIMESTAMPING_NEW:
1327 case SO_TIMESTAMPING_OLD:
1328 if (optlen == sizeof(timestamping)) {
1329 if (copy_from_sockptr(×tamping, optval,
1330 sizeof(timestamping))) {
1335 memset(×tamping, 0, sizeof(timestamping));
1336 timestamping.flags = val;
1338 ret = sock_set_timestamping(sk, optname, timestamping);
1343 int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1348 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1350 ret = set_rcvlowat(sk, val);
1352 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1355 case SO_RCVTIMEO_OLD:
1356 case SO_RCVTIMEO_NEW:
1357 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1358 optlen, optname == SO_RCVTIMEO_OLD);
1361 case SO_SNDTIMEO_OLD:
1362 case SO_SNDTIMEO_NEW:
1363 ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1364 optlen, optname == SO_SNDTIMEO_OLD);
1367 case SO_ATTACH_FILTER: {
1368 struct sock_fprog fprog;
1370 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1372 ret = sk_attach_filter(&fprog, sk);
1377 if (optlen == sizeof(u32)) {
1381 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1384 ret = sk_attach_bpf(ufd, sk);
1388 case SO_ATTACH_REUSEPORT_CBPF: {
1389 struct sock_fprog fprog;
1391 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1393 ret = sk_reuseport_attach_filter(&fprog, sk);
1396 case SO_ATTACH_REUSEPORT_EBPF:
1398 if (optlen == sizeof(u32)) {
1402 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1405 ret = sk_reuseport_attach_bpf(ufd, sk);
1409 case SO_DETACH_REUSEPORT_BPF:
1410 ret = reuseport_detach_prog(sk);
1413 case SO_DETACH_FILTER:
1414 ret = sk_detach_filter(sk);
1417 case SO_LOCK_FILTER:
1418 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1421 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1425 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1426 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1431 __sock_set_mark(sk, val);
1434 sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1438 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1441 case SO_WIFI_STATUS:
1442 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1446 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1449 case SO_SELECT_ERR_QUEUE:
1450 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1454 case SO_INCOMING_CPU:
1455 reuseport_update_incoming_cpu(sk, val);
1460 dst_negative_advice(sk);
1464 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1465 if (!(sk_is_tcp(sk) ||
1466 (sk->sk_type == SOCK_DGRAM &&
1467 sk->sk_protocol == IPPROTO_UDP)))
1469 } else if (sk->sk_family != PF_RDS) {
1473 if (val < 0 || val > 1)
1476 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1481 if (optlen != sizeof(struct sock_txtime)) {
1484 } else if (copy_from_sockptr(&sk_txtime, optval,
1485 sizeof(struct sock_txtime))) {
1488 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1492 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1493 * scheduler has enough safe guards.
1495 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1496 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1500 sock_valbool_flag(sk, SOCK_TXTIME, true);
1501 sk->sk_clockid = sk_txtime.clockid;
1502 sk->sk_txtime_deadline_mode =
1503 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1504 sk->sk_txtime_report_errors =
1505 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1508 case SO_BINDTOIFINDEX:
1509 ret = sock_bindtoindex_locked(sk, val);
1513 if (val & ~SOCK_BUF_LOCK_MASK) {
1517 sk->sk_userlocks = val | (sk->sk_userlocks &
1518 ~SOCK_BUF_LOCK_MASK);
1521 case SO_RESERVE_MEM:
1530 delta = val - sk->sk_reserved_mem;
1532 sock_release_reserved_memory(sk, -delta);
1534 ret = sock_reserve_memory(sk, delta);
1542 sockopt_release_sock(sk);
1546 int sock_setsockopt(struct socket *sock, int level, int optname,
1547 sockptr_t optval, unsigned int optlen)
1549 return sk_setsockopt(sock->sk, level, optname,
1552 EXPORT_SYMBOL(sock_setsockopt);
1554 static const struct cred *sk_get_peer_cred(struct sock *sk)
1556 const struct cred *cred;
1558 spin_lock(&sk->sk_peer_lock);
1559 cred = get_cred(sk->sk_peer_cred);
1560 spin_unlock(&sk->sk_peer_lock);
1565 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1566 struct ucred *ucred)
1568 ucred->pid = pid_vnr(pid);
1569 ucred->uid = ucred->gid = -1;
1571 struct user_namespace *current_ns = current_user_ns();
1573 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1574 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1578 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1580 struct user_namespace *user_ns = current_user_ns();
1583 for (i = 0; i < src->ngroups; i++) {
1584 gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1586 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1593 int sk_getsockopt(struct sock *sk, int level, int optname,
1594 sockptr_t optval, sockptr_t optlen)
1596 struct socket *sock = sk->sk_socket;
1601 unsigned long ulval;
1603 struct old_timeval32 tm32;
1604 struct __kernel_old_timeval tm;
1605 struct __kernel_sock_timeval stm;
1606 struct sock_txtime txtime;
1607 struct so_timestamping timestamping;
1610 int lv = sizeof(int);
1613 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1618 memset(&v, 0, sizeof(v));
1622 v.val = sock_flag(sk, SOCK_DBG);
1626 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1630 v.val = sock_flag(sk, SOCK_BROADCAST);
1634 v.val = READ_ONCE(sk->sk_sndbuf);
1638 v.val = READ_ONCE(sk->sk_rcvbuf);
1642 v.val = sk->sk_reuse;
1646 v.val = sk->sk_reuseport;
1650 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1654 v.val = sk->sk_type;
1658 v.val = sk->sk_protocol;
1662 v.val = sk->sk_family;
1666 v.val = -sock_error(sk);
1668 v.val = xchg(&sk->sk_err_soft, 0);
1672 v.val = sock_flag(sk, SOCK_URGINLINE);
1676 v.val = sk->sk_no_check_tx;
1680 v.val = READ_ONCE(sk->sk_priority);
1684 lv = sizeof(v.ling);
1685 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1686 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ;
1692 case SO_TIMESTAMP_OLD:
1693 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1694 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1695 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1698 case SO_TIMESTAMPNS_OLD:
1699 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1702 case SO_TIMESTAMP_NEW:
1703 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1706 case SO_TIMESTAMPNS_NEW:
1707 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1710 case SO_TIMESTAMPING_OLD:
1711 case SO_TIMESTAMPING_NEW:
1712 lv = sizeof(v.timestamping);
1713 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1714 * returning the flags when they were set through the same option.
1715 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1717 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1718 v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1719 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1723 case SO_RCVTIMEO_OLD:
1724 case SO_RCVTIMEO_NEW:
1725 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1726 SO_RCVTIMEO_OLD == optname);
1729 case SO_SNDTIMEO_OLD:
1730 case SO_SNDTIMEO_NEW:
1731 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1732 SO_SNDTIMEO_OLD == optname);
1736 v.val = READ_ONCE(sk->sk_rcvlowat);
1744 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1748 v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1753 struct ucred peercred;
1754 if (len > sizeof(peercred))
1755 len = sizeof(peercred);
1757 spin_lock(&sk->sk_peer_lock);
1758 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1759 spin_unlock(&sk->sk_peer_lock);
1761 if (copy_to_sockptr(optval, &peercred, len))
1768 struct pid *peer_pid;
1769 struct file *pidfd_file = NULL;
1772 if (len > sizeof(pidfd))
1773 len = sizeof(pidfd);
1775 spin_lock(&sk->sk_peer_lock);
1776 peer_pid = get_pid(sk->sk_peer_pid);
1777 spin_unlock(&sk->sk_peer_lock);
1782 pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file);
1787 if (copy_to_sockptr(optval, &pidfd, len) ||
1788 copy_to_sockptr(optlen, &len, sizeof(int))) {
1789 put_unused_fd(pidfd);
1795 fd_install(pidfd, pidfd_file);
1801 const struct cred *cred;
1804 cred = sk_get_peer_cred(sk);
1808 n = cred->group_info->ngroups;
1809 if (len < n * sizeof(gid_t)) {
1810 len = n * sizeof(gid_t);
1812 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1814 len = n * sizeof(gid_t);
1816 ret = groups_to_user(optval, cred->group_info);
1825 struct sockaddr_storage address;
1827 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1832 if (copy_to_sockptr(optval, &address, len))
1837 /* Dubious BSD thing... Probably nobody even uses it, but
1838 * the UNIX standard wants it for whatever reason... -DaveM
1841 v.val = sk->sk_state == TCP_LISTEN;
1845 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1849 return security_socket_getpeersec_stream(sock,
1850 optval, optlen, len);
1853 v.val = READ_ONCE(sk->sk_mark);
1857 v.val = sock_flag(sk, SOCK_RCVMARK);
1861 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1864 case SO_WIFI_STATUS:
1865 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1869 if (!READ_ONCE(sock->ops)->set_peek_off)
1872 v.val = READ_ONCE(sk->sk_peek_off);
1875 v.val = sock_flag(sk, SOCK_NOFCS);
1878 case SO_BINDTODEVICE:
1879 return sock_getbindtodevice(sk, optval, optlen, len);
1882 len = sk_get_filter(sk, optval, len);
1888 case SO_LOCK_FILTER:
1889 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1892 case SO_BPF_EXTENSIONS:
1893 v.val = bpf_tell_extensions();
1896 case SO_SELECT_ERR_QUEUE:
1897 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1900 #ifdef CONFIG_NET_RX_BUSY_POLL
1902 v.val = READ_ONCE(sk->sk_ll_usec);
1904 case SO_PREFER_BUSY_POLL:
1905 v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1909 case SO_MAX_PACING_RATE:
1910 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
1911 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1912 lv = sizeof(v.ulval);
1913 v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
1916 v.val = min_t(unsigned long, ~0U,
1917 READ_ONCE(sk->sk_max_pacing_rate));
1921 case SO_INCOMING_CPU:
1922 v.val = READ_ONCE(sk->sk_incoming_cpu);
1927 u32 meminfo[SK_MEMINFO_VARS];
1929 sk_get_meminfo(sk, meminfo);
1931 len = min_t(unsigned int, len, sizeof(meminfo));
1932 if (copy_to_sockptr(optval, &meminfo, len))
1938 #ifdef CONFIG_NET_RX_BUSY_POLL
1939 case SO_INCOMING_NAPI_ID:
1940 v.val = READ_ONCE(sk->sk_napi_id);
1942 /* aggregate non-NAPI IDs down to 0 */
1943 if (v.val < MIN_NAPI_ID)
1953 v.val64 = sock_gen_cookie(sk);
1957 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1961 lv = sizeof(v.txtime);
1962 v.txtime.clockid = sk->sk_clockid;
1963 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1964 SOF_TXTIME_DEADLINE_MODE : 0;
1965 v.txtime.flags |= sk->sk_txtime_report_errors ?
1966 SOF_TXTIME_REPORT_ERRORS : 0;
1969 case SO_BINDTOIFINDEX:
1970 v.val = READ_ONCE(sk->sk_bound_dev_if);
1973 case SO_NETNS_COOKIE:
1977 v.val64 = sock_net(sk)->net_cookie;
1981 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1984 case SO_RESERVE_MEM:
1985 v.val = READ_ONCE(sk->sk_reserved_mem);
1989 /* Paired with WRITE_ONCE() in sk_setsockopt() */
1990 v.val = READ_ONCE(sk->sk_txrehash);
1994 /* We implement the SO_SNDLOWAT etc to not be settable
1997 return -ENOPROTOOPT;
2002 if (copy_to_sockptr(optval, &v, len))
2005 if (copy_to_sockptr(optlen, &len, sizeof(int)))
2011 * Initialize an sk_lock.
2013 * (We also register the sk_lock with the lock validator.)
2015 static inline void sock_lock_init(struct sock *sk)
2017 if (sk->sk_kern_sock)
2018 sock_lock_init_class_and_name(
2020 af_family_kern_slock_key_strings[sk->sk_family],
2021 af_family_kern_slock_keys + sk->sk_family,
2022 af_family_kern_key_strings[sk->sk_family],
2023 af_family_kern_keys + sk->sk_family);
2025 sock_lock_init_class_and_name(
2027 af_family_slock_key_strings[sk->sk_family],
2028 af_family_slock_keys + sk->sk_family,
2029 af_family_key_strings[sk->sk_family],
2030 af_family_keys + sk->sk_family);
2034 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2035 * even temporarly, because of RCU lookups. sk_node should also be left as is.
2036 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2038 static void sock_copy(struct sock *nsk, const struct sock *osk)
2040 const struct proto *prot = READ_ONCE(osk->sk_prot);
2041 #ifdef CONFIG_SECURITY_NETWORK
2042 void *sptr = nsk->sk_security;
2045 /* If we move sk_tx_queue_mapping out of the private section,
2046 * we must check if sk_tx_queue_clear() is called after
2047 * sock_copy() in sk_clone_lock().
2049 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2050 offsetof(struct sock, sk_dontcopy_begin) ||
2051 offsetof(struct sock, sk_tx_queue_mapping) >=
2052 offsetof(struct sock, sk_dontcopy_end));
2054 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2056 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2057 prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2059 #ifdef CONFIG_SECURITY_NETWORK
2060 nsk->sk_security = sptr;
2061 security_sk_clone(osk, nsk);
2065 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2069 struct kmem_cache *slab;
2073 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2076 if (want_init_on_alloc(priority))
2077 sk_prot_clear_nulls(sk, prot->obj_size);
2079 sk = kmalloc(prot->obj_size, priority);
2082 if (security_sk_alloc(sk, family, priority))
2085 if (!try_module_get(prot->owner))
2092 security_sk_free(sk);
2095 kmem_cache_free(slab, sk);
2101 static void sk_prot_free(struct proto *prot, struct sock *sk)
2103 struct kmem_cache *slab;
2104 struct module *owner;
2106 owner = prot->owner;
2109 cgroup_sk_free(&sk->sk_cgrp_data);
2110 mem_cgroup_sk_free(sk);
2111 security_sk_free(sk);
2113 kmem_cache_free(slab, sk);
2120 * sk_alloc - All socket objects are allocated here
2121 * @net: the applicable net namespace
2122 * @family: protocol family
2123 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2124 * @prot: struct proto associated with this new sock instance
2125 * @kern: is this to be a kernel socket?
2127 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2128 struct proto *prot, int kern)
2132 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2134 sk->sk_family = family;
2136 * See comment in struct sock definition to understand
2137 * why we need sk_prot_creator -acme
2139 sk->sk_prot = sk->sk_prot_creator = prot;
2140 sk->sk_kern_sock = kern;
2142 sk->sk_net_refcnt = kern ? 0 : 1;
2143 if (likely(sk->sk_net_refcnt)) {
2144 get_net_track(net, &sk->ns_tracker, priority);
2145 sock_inuse_add(net, 1);
2147 __netns_tracker_alloc(net, &sk->ns_tracker,
2151 sock_net_set(sk, net);
2152 refcount_set(&sk->sk_wmem_alloc, 1);
2154 mem_cgroup_sk_alloc(sk);
2155 cgroup_sk_alloc(&sk->sk_cgrp_data);
2156 sock_update_classid(&sk->sk_cgrp_data);
2157 sock_update_netprioidx(&sk->sk_cgrp_data);
2158 sk_tx_queue_clear(sk);
2163 EXPORT_SYMBOL(sk_alloc);
2165 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2166 * grace period. This is the case for UDP sockets and TCP listeners.
2168 static void __sk_destruct(struct rcu_head *head)
2170 struct sock *sk = container_of(head, struct sock, sk_rcu);
2171 struct sk_filter *filter;
2173 if (sk->sk_destruct)
2174 sk->sk_destruct(sk);
2176 filter = rcu_dereference_check(sk->sk_filter,
2177 refcount_read(&sk->sk_wmem_alloc) == 0);
2179 sk_filter_uncharge(sk, filter);
2180 RCU_INIT_POINTER(sk->sk_filter, NULL);
2183 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2185 #ifdef CONFIG_BPF_SYSCALL
2186 bpf_sk_storage_free(sk);
2189 if (atomic_read(&sk->sk_omem_alloc))
2190 pr_debug("%s: optmem leakage (%d bytes) detected\n",
2191 __func__, atomic_read(&sk->sk_omem_alloc));
2193 if (sk->sk_frag.page) {
2194 put_page(sk->sk_frag.page);
2195 sk->sk_frag.page = NULL;
2198 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2199 put_cred(sk->sk_peer_cred);
2200 put_pid(sk->sk_peer_pid);
2202 if (likely(sk->sk_net_refcnt))
2203 put_net_track(sock_net(sk), &sk->ns_tracker);
2205 __netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2207 sk_prot_free(sk->sk_prot_creator, sk);
2210 void sk_destruct(struct sock *sk)
2212 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2214 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2215 reuseport_detach_sock(sk);
2216 use_call_rcu = true;
2220 call_rcu(&sk->sk_rcu, __sk_destruct);
2222 __sk_destruct(&sk->sk_rcu);
2225 static void __sk_free(struct sock *sk)
2227 if (likely(sk->sk_net_refcnt))
2228 sock_inuse_add(sock_net(sk), -1);
2230 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2231 sock_diag_broadcast_destroy(sk);
2236 void sk_free(struct sock *sk)
2239 * We subtract one from sk_wmem_alloc and can know if
2240 * some packets are still in some tx queue.
2241 * If not null, sock_wfree() will call __sk_free(sk) later
2243 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2246 EXPORT_SYMBOL(sk_free);
2248 static void sk_init_common(struct sock *sk)
2250 skb_queue_head_init(&sk->sk_receive_queue);
2251 skb_queue_head_init(&sk->sk_write_queue);
2252 skb_queue_head_init(&sk->sk_error_queue);
2254 rwlock_init(&sk->sk_callback_lock);
2255 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2256 af_rlock_keys + sk->sk_family,
2257 af_family_rlock_key_strings[sk->sk_family]);
2258 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2259 af_wlock_keys + sk->sk_family,
2260 af_family_wlock_key_strings[sk->sk_family]);
2261 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2262 af_elock_keys + sk->sk_family,
2263 af_family_elock_key_strings[sk->sk_family]);
2264 lockdep_set_class_and_name(&sk->sk_callback_lock,
2265 af_callback_keys + sk->sk_family,
2266 af_family_clock_key_strings[sk->sk_family]);
2270 * sk_clone_lock - clone a socket, and lock its clone
2271 * @sk: the socket to clone
2272 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2274 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2276 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2278 struct proto *prot = READ_ONCE(sk->sk_prot);
2279 struct sk_filter *filter;
2280 bool is_charged = true;
2283 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2287 sock_copy(newsk, sk);
2289 newsk->sk_prot_creator = prot;
2292 if (likely(newsk->sk_net_refcnt)) {
2293 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2294 sock_inuse_add(sock_net(newsk), 1);
2296 /* Kernel sockets are not elevating the struct net refcount.
2297 * Instead, use a tracker to more easily detect if a layer
2298 * is not properly dismantling its kernel sockets at netns
2301 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2304 sk_node_init(&newsk->sk_node);
2305 sock_lock_init(newsk);
2306 bh_lock_sock(newsk);
2307 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
2308 newsk->sk_backlog.len = 0;
2310 atomic_set(&newsk->sk_rmem_alloc, 0);
2312 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2313 refcount_set(&newsk->sk_wmem_alloc, 1);
2315 atomic_set(&newsk->sk_omem_alloc, 0);
2316 sk_init_common(newsk);
2318 newsk->sk_dst_cache = NULL;
2319 newsk->sk_dst_pending_confirm = 0;
2320 newsk->sk_wmem_queued = 0;
2321 newsk->sk_forward_alloc = 0;
2322 newsk->sk_reserved_mem = 0;
2323 atomic_set(&newsk->sk_drops, 0);
2324 newsk->sk_send_head = NULL;
2325 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2326 atomic_set(&newsk->sk_zckey, 0);
2328 sock_reset_flag(newsk, SOCK_DONE);
2330 /* sk->sk_memcg will be populated at accept() time */
2331 newsk->sk_memcg = NULL;
2333 cgroup_sk_clone(&newsk->sk_cgrp_data);
2336 filter = rcu_dereference(sk->sk_filter);
2338 /* though it's an empty new sock, the charging may fail
2339 * if sysctl_optmem_max was changed between creation of
2340 * original socket and cloning
2342 is_charged = sk_filter_charge(newsk, filter);
2343 RCU_INIT_POINTER(newsk->sk_filter, filter);
2346 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2347 /* We need to make sure that we don't uncharge the new
2348 * socket if we couldn't charge it in the first place
2349 * as otherwise we uncharge the parent's filter.
2352 RCU_INIT_POINTER(newsk->sk_filter, NULL);
2353 sk_free_unlock_clone(newsk);
2357 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2359 if (bpf_sk_storage_clone(sk, newsk)) {
2360 sk_free_unlock_clone(newsk);
2365 /* Clear sk_user_data if parent had the pointer tagged
2366 * as not suitable for copying when cloning.
2368 if (sk_user_data_is_nocopy(newsk))
2369 newsk->sk_user_data = NULL;
2372 newsk->sk_err_soft = 0;
2373 newsk->sk_priority = 0;
2374 newsk->sk_incoming_cpu = raw_smp_processor_id();
2376 /* Before updating sk_refcnt, we must commit prior changes to memory
2377 * (Documentation/RCU/rculist_nulls.rst for details)
2380 refcount_set(&newsk->sk_refcnt, 2);
2382 sk_set_socket(newsk, NULL);
2383 sk_tx_queue_clear(newsk);
2384 RCU_INIT_POINTER(newsk->sk_wq, NULL);
2386 if (newsk->sk_prot->sockets_allocated)
2387 sk_sockets_allocated_inc(newsk);
2389 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2390 net_enable_timestamp();
2394 EXPORT_SYMBOL_GPL(sk_clone_lock);
2396 void sk_free_unlock_clone(struct sock *sk)
2398 /* It is still raw copy of parent, so invalidate
2399 * destructor and make plain sk_free() */
2400 sk->sk_destruct = NULL;
2404 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2406 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2408 bool is_ipv6 = false;
2411 #if IS_ENABLED(CONFIG_IPV6)
2412 is_ipv6 = (sk->sk_family == AF_INET6 &&
2413 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2415 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2416 max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2417 READ_ONCE(dst->dev->gso_ipv4_max_size);
2418 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2419 max_size = GSO_LEGACY_MAX_SIZE;
2421 return max_size - (MAX_TCP_HEADER + 1);
2424 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2428 sk->sk_route_caps = dst->dev->features;
2430 sk->sk_route_caps |= NETIF_F_GSO;
2431 if (sk->sk_route_caps & NETIF_F_GSO)
2432 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2433 if (unlikely(sk->sk_gso_disabled))
2434 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2435 if (sk_can_gso(sk)) {
2436 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2437 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2439 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2440 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2441 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2442 max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2445 sk->sk_gso_max_segs = max_segs;
2446 sk_dst_set(sk, dst);
2448 EXPORT_SYMBOL_GPL(sk_setup_caps);
2451 * Simple resource managers for sockets.
2456 * Write buffer destructor automatically called from kfree_skb.
2458 void sock_wfree(struct sk_buff *skb)
2460 struct sock *sk = skb->sk;
2461 unsigned int len = skb->truesize;
2464 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2465 if (sock_flag(sk, SOCK_RCU_FREE) &&
2466 sk->sk_write_space == sock_def_write_space) {
2468 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2469 sock_def_write_space_wfree(sk);
2477 * Keep a reference on sk_wmem_alloc, this will be released
2478 * after sk_write_space() call
2480 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2481 sk->sk_write_space(sk);
2485 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2486 * could not do because of in-flight packets
2488 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2491 EXPORT_SYMBOL(sock_wfree);
2493 /* This variant of sock_wfree() is used by TCP,
2494 * since it sets SOCK_USE_WRITE_QUEUE.
2496 void __sock_wfree(struct sk_buff *skb)
2498 struct sock *sk = skb->sk;
2500 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2504 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2509 if (unlikely(!sk_fullsock(sk))) {
2510 skb->destructor = sock_edemux;
2515 skb->destructor = sock_wfree;
2516 skb_set_hash_from_sk(skb, sk);
2518 * We used to take a refcount on sk, but following operation
2519 * is enough to guarantee sk_free() wont free this sock until
2520 * all in-flight packets are completed
2522 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2524 EXPORT_SYMBOL(skb_set_owner_w);
2526 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2528 #ifdef CONFIG_TLS_DEVICE
2529 /* Drivers depend on in-order delivery for crypto offload,
2530 * partial orphan breaks out-of-order-OK logic.
2535 return (skb->destructor == sock_wfree ||
2536 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2539 /* This helper is used by netem, as it can hold packets in its
2540 * delay queue. We want to allow the owner socket to send more
2541 * packets, as if they were already TX completed by a typical driver.
2542 * But we also want to keep skb->sk set because some packet schedulers
2543 * rely on it (sch_fq for example).
2545 void skb_orphan_partial(struct sk_buff *skb)
2547 if (skb_is_tcp_pure_ack(skb))
2550 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2555 EXPORT_SYMBOL(skb_orphan_partial);
2558 * Read buffer destructor automatically called from kfree_skb.
2560 void sock_rfree(struct sk_buff *skb)
2562 struct sock *sk = skb->sk;
2563 unsigned int len = skb->truesize;
2565 atomic_sub(len, &sk->sk_rmem_alloc);
2566 sk_mem_uncharge(sk, len);
2568 EXPORT_SYMBOL(sock_rfree);
2571 * Buffer destructor for skbs that are not used directly in read or write
2572 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2574 void sock_efree(struct sk_buff *skb)
2578 EXPORT_SYMBOL(sock_efree);
2580 /* Buffer destructor for prefetch/receive path where reference count may
2581 * not be held, e.g. for listen sockets.
2584 void sock_pfree(struct sk_buff *skb)
2586 if (sk_is_refcounted(skb->sk))
2587 sock_gen_put(skb->sk);
2589 EXPORT_SYMBOL(sock_pfree);
2590 #endif /* CONFIG_INET */
2592 kuid_t sock_i_uid(struct sock *sk)
2596 read_lock_bh(&sk->sk_callback_lock);
2597 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2598 read_unlock_bh(&sk->sk_callback_lock);
2601 EXPORT_SYMBOL(sock_i_uid);
2603 unsigned long __sock_i_ino(struct sock *sk)
2607 read_lock(&sk->sk_callback_lock);
2608 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2609 read_unlock(&sk->sk_callback_lock);
2612 EXPORT_SYMBOL(__sock_i_ino);
2614 unsigned long sock_i_ino(struct sock *sk)
2619 ino = __sock_i_ino(sk);
2623 EXPORT_SYMBOL(sock_i_ino);
2626 * Allocate a skb from the socket's send buffer.
2628 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2632 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2633 struct sk_buff *skb = alloc_skb(size, priority);
2636 skb_set_owner_w(skb, sk);
2642 EXPORT_SYMBOL(sock_wmalloc);
2644 static void sock_ofree(struct sk_buff *skb)
2646 struct sock *sk = skb->sk;
2648 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2651 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2654 struct sk_buff *skb;
2656 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2657 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2658 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2661 skb = alloc_skb(size, priority);
2665 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2667 skb->destructor = sock_ofree;
2672 * Allocate a memory block from the socket's option memory buffer.
2674 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2676 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2678 if ((unsigned int)size <= optmem_max &&
2679 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2681 /* First do the add, to avoid the race if kmalloc
2684 atomic_add(size, &sk->sk_omem_alloc);
2685 mem = kmalloc(size, priority);
2688 atomic_sub(size, &sk->sk_omem_alloc);
2692 EXPORT_SYMBOL(sock_kmalloc);
2694 /* Free an option memory block. Note, we actually want the inline
2695 * here as this allows gcc to detect the nullify and fold away the
2696 * condition entirely.
2698 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2701 if (WARN_ON_ONCE(!mem))
2704 kfree_sensitive(mem);
2707 atomic_sub(size, &sk->sk_omem_alloc);
2710 void sock_kfree_s(struct sock *sk, void *mem, int size)
2712 __sock_kfree_s(sk, mem, size, false);
2714 EXPORT_SYMBOL(sock_kfree_s);
2716 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2718 __sock_kfree_s(sk, mem, size, true);
2720 EXPORT_SYMBOL(sock_kzfree_s);
2722 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2723 I think, these locks should be removed for datagram sockets.
2725 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2729 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2733 if (signal_pending(current))
2735 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2736 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2737 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2739 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2741 if (READ_ONCE(sk->sk_err))
2743 timeo = schedule_timeout(timeo);
2745 finish_wait(sk_sleep(sk), &wait);
2751 * Generic send/receive buffer handlers
2754 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2755 unsigned long data_len, int noblock,
2756 int *errcode, int max_page_order)
2758 struct sk_buff *skb;
2762 timeo = sock_sndtimeo(sk, noblock);
2764 err = sock_error(sk);
2769 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2772 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2775 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2776 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2780 if (signal_pending(current))
2782 timeo = sock_wait_for_wmem(sk, timeo);
2784 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2785 errcode, sk->sk_allocation);
2787 skb_set_owner_w(skb, sk);
2791 err = sock_intr_errno(timeo);
2796 EXPORT_SYMBOL(sock_alloc_send_pskb);
2798 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2799 struct sockcm_cookie *sockc)
2803 switch (cmsg->cmsg_type) {
2805 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2806 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2808 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2810 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2812 case SO_TIMESTAMPING_OLD:
2813 case SO_TIMESTAMPING_NEW:
2814 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2817 tsflags = *(u32 *)CMSG_DATA(cmsg);
2818 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2821 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2822 sockc->tsflags |= tsflags;
2825 if (!sock_flag(sk, SOCK_TXTIME))
2827 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2829 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2831 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2833 case SCM_CREDENTIALS:
2840 EXPORT_SYMBOL(__sock_cmsg_send);
2842 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2843 struct sockcm_cookie *sockc)
2845 struct cmsghdr *cmsg;
2848 for_each_cmsghdr(cmsg, msg) {
2849 if (!CMSG_OK(msg, cmsg))
2851 if (cmsg->cmsg_level != SOL_SOCKET)
2853 ret = __sock_cmsg_send(sk, cmsg, sockc);
2859 EXPORT_SYMBOL(sock_cmsg_send);
2861 static void sk_enter_memory_pressure(struct sock *sk)
2863 if (!sk->sk_prot->enter_memory_pressure)
2866 sk->sk_prot->enter_memory_pressure(sk);
2869 static void sk_leave_memory_pressure(struct sock *sk)
2871 if (sk->sk_prot->leave_memory_pressure) {
2872 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2873 tcp_leave_memory_pressure, sk);
2875 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2877 if (memory_pressure && READ_ONCE(*memory_pressure))
2878 WRITE_ONCE(*memory_pressure, 0);
2882 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2885 * skb_page_frag_refill - check that a page_frag contains enough room
2886 * @sz: minimum size of the fragment we want to get
2887 * @pfrag: pointer to page_frag
2888 * @gfp: priority for memory allocation
2890 * Note: While this allocator tries to use high order pages, there is
2891 * no guarantee that allocations succeed. Therefore, @sz MUST be
2892 * less or equal than PAGE_SIZE.
2894 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2897 if (page_ref_count(pfrag->page) == 1) {
2901 if (pfrag->offset + sz <= pfrag->size)
2903 put_page(pfrag->page);
2907 if (SKB_FRAG_PAGE_ORDER &&
2908 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2909 /* Avoid direct reclaim but allow kswapd to wake */
2910 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2911 __GFP_COMP | __GFP_NOWARN |
2913 SKB_FRAG_PAGE_ORDER);
2914 if (likely(pfrag->page)) {
2915 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2919 pfrag->page = alloc_page(gfp);
2920 if (likely(pfrag->page)) {
2921 pfrag->size = PAGE_SIZE;
2926 EXPORT_SYMBOL(skb_page_frag_refill);
2928 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2930 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2933 sk_enter_memory_pressure(sk);
2934 sk_stream_moderate_sndbuf(sk);
2937 EXPORT_SYMBOL(sk_page_frag_refill);
2939 void __lock_sock(struct sock *sk)
2940 __releases(&sk->sk_lock.slock)
2941 __acquires(&sk->sk_lock.slock)
2946 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2947 TASK_UNINTERRUPTIBLE);
2948 spin_unlock_bh(&sk->sk_lock.slock);
2950 spin_lock_bh(&sk->sk_lock.slock);
2951 if (!sock_owned_by_user(sk))
2954 finish_wait(&sk->sk_lock.wq, &wait);
2957 void __release_sock(struct sock *sk)
2958 __releases(&sk->sk_lock.slock)
2959 __acquires(&sk->sk_lock.slock)
2961 struct sk_buff *skb, *next;
2963 while ((skb = sk->sk_backlog.head) != NULL) {
2964 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2966 spin_unlock_bh(&sk->sk_lock.slock);
2971 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2972 skb_mark_not_on_list(skb);
2973 sk_backlog_rcv(sk, skb);
2978 } while (skb != NULL);
2980 spin_lock_bh(&sk->sk_lock.slock);
2984 * Doing the zeroing here guarantee we can not loop forever
2985 * while a wild producer attempts to flood us.
2987 sk->sk_backlog.len = 0;
2990 void __sk_flush_backlog(struct sock *sk)
2992 spin_lock_bh(&sk->sk_lock.slock);
2995 if (sk->sk_prot->release_cb)
2996 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
2997 tcp_release_cb, sk);
2999 spin_unlock_bh(&sk->sk_lock.slock);
3001 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3004 * sk_wait_data - wait for data to arrive at sk_receive_queue
3005 * @sk: sock to wait on
3006 * @timeo: for how long
3007 * @skb: last skb seen on sk_receive_queue
3009 * Now socket state including sk->sk_err is changed only under lock,
3010 * hence we may omit checks after joining wait queue.
3011 * We check receive queue before schedule() only as optimization;
3012 * it is very likely that release_sock() added new data.
3014 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3016 DEFINE_WAIT_FUNC(wait, woken_wake_function);
3019 add_wait_queue(sk_sleep(sk), &wait);
3020 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3021 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3022 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3023 remove_wait_queue(sk_sleep(sk), &wait);
3026 EXPORT_SYMBOL(sk_wait_data);
3029 * __sk_mem_raise_allocated - increase memory_allocated
3031 * @size: memory size to allocate
3032 * @amt: pages to allocate
3033 * @kind: allocation type
3035 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3037 * Unlike the globally shared limits among the sockets under same protocol,
3038 * consuming the budget of a memcg won't have direct effect on other ones.
3039 * So be optimistic about memcg's tolerance, and leave the callers to decide
3040 * whether or not to raise allocated through sk_under_memory_pressure() or
3043 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3045 struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3046 struct proto *prot = sk->sk_prot;
3047 bool charged = false;
3050 sk_memory_allocated_add(sk, amt);
3051 allocated = sk_memory_allocated(sk);
3054 if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3055 goto suppress_allocation;
3060 if (allocated <= sk_prot_mem_limits(sk, 0)) {
3061 sk_leave_memory_pressure(sk);
3065 /* Under pressure. */
3066 if (allocated > sk_prot_mem_limits(sk, 1))
3067 sk_enter_memory_pressure(sk);
3069 /* Over hard limit. */
3070 if (allocated > sk_prot_mem_limits(sk, 2))
3071 goto suppress_allocation;
3073 /* Guarantee minimum buffer size under pressure (either global
3074 * or memcg) to make sure features described in RFC 7323 (TCP
3075 * Extensions for High Performance) work properly.
3077 * This rule does NOT stand when exceeds global or memcg's hard
3078 * limit, or else a DoS attack can be taken place by spawning
3079 * lots of sockets whose usage are under minimum buffer size.
3081 if (kind == SK_MEM_RECV) {
3082 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3085 } else { /* SK_MEM_SEND */
3086 int wmem0 = sk_get_wmem0(sk, prot);
3088 if (sk->sk_type == SOCK_STREAM) {
3089 if (sk->sk_wmem_queued < wmem0)
3091 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3096 if (sk_has_memory_pressure(sk)) {
3099 /* The following 'average' heuristic is within the
3100 * scope of global accounting, so it only makes
3101 * sense for global memory pressure.
3103 if (!sk_under_global_memory_pressure(sk))
3106 /* Try to be fair among all the sockets under global
3107 * pressure by allowing the ones that below average
3110 alloc = sk_sockets_allocated_read_positive(sk);
3111 if (sk_prot_mem_limits(sk, 2) > alloc *
3112 sk_mem_pages(sk->sk_wmem_queued +
3113 atomic_read(&sk->sk_rmem_alloc) +
3114 sk->sk_forward_alloc))
3118 suppress_allocation:
3120 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3121 sk_stream_moderate_sndbuf(sk);
3123 /* Fail only if socket is _under_ its sndbuf.
3124 * In this case we cannot block, so that we have to fail.
3126 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3127 /* Force charge with __GFP_NOFAIL */
3128 if (memcg && !charged) {
3129 mem_cgroup_charge_skmem(memcg, amt,
3130 gfp_memcg_charge() | __GFP_NOFAIL);
3136 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3137 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3139 sk_memory_allocated_sub(sk, amt);
3142 mem_cgroup_uncharge_skmem(memcg, amt);
3148 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3150 * @size: memory size to allocate
3151 * @kind: allocation type
3153 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3154 * rmem allocation. This function assumes that protocols which have
3155 * memory_pressure use sk_wmem_queued as write buffer accounting.
3157 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3159 int ret, amt = sk_mem_pages(size);
3161 sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3162 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3164 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3167 EXPORT_SYMBOL(__sk_mem_schedule);
3170 * __sk_mem_reduce_allocated - reclaim memory_allocated
3172 * @amount: number of quanta
3174 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3176 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3178 sk_memory_allocated_sub(sk, amount);
3180 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3181 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3183 if (sk_under_global_memory_pressure(sk) &&
3184 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3185 sk_leave_memory_pressure(sk);
3189 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3191 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3193 void __sk_mem_reclaim(struct sock *sk, int amount)
3195 amount >>= PAGE_SHIFT;
3196 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3197 __sk_mem_reduce_allocated(sk, amount);
3199 EXPORT_SYMBOL(__sk_mem_reclaim);
3201 int sk_set_peek_off(struct sock *sk, int val)
3203 WRITE_ONCE(sk->sk_peek_off, val);
3206 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3209 * Set of default routines for initialising struct proto_ops when
3210 * the protocol does not support a particular function. In certain
3211 * cases where it makes no sense for a protocol to have a "do nothing"
3212 * function, some default processing is provided.
3215 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3219 EXPORT_SYMBOL(sock_no_bind);
3221 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3226 EXPORT_SYMBOL(sock_no_connect);
3228 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3232 EXPORT_SYMBOL(sock_no_socketpair);
3234 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3239 EXPORT_SYMBOL(sock_no_accept);
3241 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3246 EXPORT_SYMBOL(sock_no_getname);
3248 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3252 EXPORT_SYMBOL(sock_no_ioctl);
3254 int sock_no_listen(struct socket *sock, int backlog)
3258 EXPORT_SYMBOL(sock_no_listen);
3260 int sock_no_shutdown(struct socket *sock, int how)
3264 EXPORT_SYMBOL(sock_no_shutdown);
3266 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3270 EXPORT_SYMBOL(sock_no_sendmsg);
3272 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3276 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3278 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3283 EXPORT_SYMBOL(sock_no_recvmsg);
3285 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3287 /* Mirror missing mmap method error code */
3290 EXPORT_SYMBOL(sock_no_mmap);
3293 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3294 * various sock-based usage counts.
3296 void __receive_sock(struct file *file)
3298 struct socket *sock;
3300 sock = sock_from_file(file);
3302 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3303 sock_update_classid(&sock->sk->sk_cgrp_data);
3308 * Default Socket Callbacks
3311 static void sock_def_wakeup(struct sock *sk)
3313 struct socket_wq *wq;
3316 wq = rcu_dereference(sk->sk_wq);
3317 if (skwq_has_sleeper(wq))
3318 wake_up_interruptible_all(&wq->wait);
3322 static void sock_def_error_report(struct sock *sk)
3324 struct socket_wq *wq;
3327 wq = rcu_dereference(sk->sk_wq);
3328 if (skwq_has_sleeper(wq))
3329 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3330 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3334 void sock_def_readable(struct sock *sk)
3336 struct socket_wq *wq;
3338 trace_sk_data_ready(sk);
3341 wq = rcu_dereference(sk->sk_wq);
3342 if (skwq_has_sleeper(wq))
3343 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3344 EPOLLRDNORM | EPOLLRDBAND);
3345 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3349 static void sock_def_write_space(struct sock *sk)
3351 struct socket_wq *wq;
3355 /* Do not wake up a writer until he can make "significant"
3358 if (sock_writeable(sk)) {
3359 wq = rcu_dereference(sk->sk_wq);
3360 if (skwq_has_sleeper(wq))
3361 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3362 EPOLLWRNORM | EPOLLWRBAND);
3364 /* Should agree with poll, otherwise some programs break */
3365 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3371 /* An optimised version of sock_def_write_space(), should only be called
3372 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3375 static void sock_def_write_space_wfree(struct sock *sk)
3377 /* Do not wake up a writer until he can make "significant"
3380 if (sock_writeable(sk)) {
3381 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3383 /* rely on refcount_sub from sock_wfree() */
3384 smp_mb__after_atomic();
3385 if (wq && waitqueue_active(&wq->wait))
3386 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3387 EPOLLWRNORM | EPOLLWRBAND);
3389 /* Should agree with poll, otherwise some programs break */
3390 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3394 static void sock_def_destruct(struct sock *sk)
3398 void sk_send_sigurg(struct sock *sk)
3400 if (sk->sk_socket && sk->sk_socket->file)
3401 if (send_sigurg(&sk->sk_socket->file->f_owner))
3402 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3404 EXPORT_SYMBOL(sk_send_sigurg);
3406 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3407 unsigned long expires)
3409 if (!mod_timer(timer, expires))
3412 EXPORT_SYMBOL(sk_reset_timer);
3414 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3416 if (del_timer(timer))
3419 EXPORT_SYMBOL(sk_stop_timer);
3421 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3423 if (del_timer_sync(timer))
3426 EXPORT_SYMBOL(sk_stop_timer_sync);
3428 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3431 sk->sk_send_head = NULL;
3433 timer_setup(&sk->sk_timer, NULL, 0);
3435 sk->sk_allocation = GFP_KERNEL;
3436 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default);
3437 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default);
3438 sk->sk_state = TCP_CLOSE;
3439 sk->sk_use_task_frag = true;
3440 sk_set_socket(sk, sock);
3442 sock_set_flag(sk, SOCK_ZAPPED);
3445 sk->sk_type = sock->type;
3446 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3449 RCU_INIT_POINTER(sk->sk_wq, NULL);
3453 rwlock_init(&sk->sk_callback_lock);
3454 if (sk->sk_kern_sock)
3455 lockdep_set_class_and_name(
3456 &sk->sk_callback_lock,
3457 af_kern_callback_keys + sk->sk_family,
3458 af_family_kern_clock_key_strings[sk->sk_family]);
3460 lockdep_set_class_and_name(
3461 &sk->sk_callback_lock,
3462 af_callback_keys + sk->sk_family,
3463 af_family_clock_key_strings[sk->sk_family]);
3465 sk->sk_state_change = sock_def_wakeup;
3466 sk->sk_data_ready = sock_def_readable;
3467 sk->sk_write_space = sock_def_write_space;
3468 sk->sk_error_report = sock_def_error_report;
3469 sk->sk_destruct = sock_def_destruct;
3471 sk->sk_frag.page = NULL;
3472 sk->sk_frag.offset = 0;
3473 sk->sk_peek_off = -1;
3475 sk->sk_peer_pid = NULL;
3476 sk->sk_peer_cred = NULL;
3477 spin_lock_init(&sk->sk_peer_lock);
3479 sk->sk_write_pending = 0;
3480 sk->sk_rcvlowat = 1;
3481 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3482 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3484 sk->sk_stamp = SK_DEFAULT_STAMP;
3485 #if BITS_PER_LONG==32
3486 seqlock_init(&sk->sk_stamp_seq);
3488 atomic_set(&sk->sk_zckey, 0);
3490 #ifdef CONFIG_NET_RX_BUSY_POLL
3492 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read);
3495 sk->sk_max_pacing_rate = ~0UL;
3496 sk->sk_pacing_rate = ~0UL;
3497 WRITE_ONCE(sk->sk_pacing_shift, 10);
3498 sk->sk_incoming_cpu = -1;
3500 sk_rx_queue_clear(sk);
3502 * Before updating sk_refcnt, we must commit prior changes to memory
3503 * (Documentation/RCU/rculist_nulls.rst for details)
3506 refcount_set(&sk->sk_refcnt, 1);
3507 atomic_set(&sk->sk_drops, 0);
3509 EXPORT_SYMBOL(sock_init_data_uid);
3511 void sock_init_data(struct socket *sock, struct sock *sk)
3514 SOCK_INODE(sock)->i_uid :
3515 make_kuid(sock_net(sk)->user_ns, 0);
3517 sock_init_data_uid(sock, sk, uid);
3519 EXPORT_SYMBOL(sock_init_data);
3521 void lock_sock_nested(struct sock *sk, int subclass)
3523 /* The sk_lock has mutex_lock() semantics here. */
3524 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3527 spin_lock_bh(&sk->sk_lock.slock);
3528 if (sock_owned_by_user_nocheck(sk))
3530 sk->sk_lock.owned = 1;
3531 spin_unlock_bh(&sk->sk_lock.slock);
3533 EXPORT_SYMBOL(lock_sock_nested);
3535 void release_sock(struct sock *sk)
3537 spin_lock_bh(&sk->sk_lock.slock);
3538 if (sk->sk_backlog.tail)
3541 if (sk->sk_prot->release_cb)
3542 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3543 tcp_release_cb, sk);
3545 sock_release_ownership(sk);
3546 if (waitqueue_active(&sk->sk_lock.wq))
3547 wake_up(&sk->sk_lock.wq);
3548 spin_unlock_bh(&sk->sk_lock.slock);
3550 EXPORT_SYMBOL(release_sock);
3552 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3555 spin_lock_bh(&sk->sk_lock.slock);
3557 if (!sock_owned_by_user_nocheck(sk)) {
3559 * Fast path return with bottom halves disabled and
3560 * sock::sk_lock.slock held.
3562 * The 'mutex' is not contended and holding
3563 * sock::sk_lock.slock prevents all other lockers to
3564 * proceed so the corresponding unlock_sock_fast() can
3565 * avoid the slow path of release_sock() completely and
3566 * just release slock.
3568 * From a semantical POV this is equivalent to 'acquiring'
3569 * the 'mutex', hence the corresponding lockdep
3570 * mutex_release() has to happen in the fast path of
3571 * unlock_sock_fast().
3577 sk->sk_lock.owned = 1;
3578 __acquire(&sk->sk_lock.slock);
3579 spin_unlock_bh(&sk->sk_lock.slock);
3582 EXPORT_SYMBOL(__lock_sock_fast);
3584 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3585 bool timeval, bool time32)
3587 struct sock *sk = sock->sk;
3588 struct timespec64 ts;
3590 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3591 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3592 if (ts.tv_sec == -1)
3594 if (ts.tv_sec == 0) {
3595 ktime_t kt = ktime_get_real();
3596 sock_write_timestamp(sk, kt);
3597 ts = ktime_to_timespec64(kt);
3603 #ifdef CONFIG_COMPAT_32BIT_TIME
3605 return put_old_timespec32(&ts, userstamp);
3607 #ifdef CONFIG_SPARC64
3608 /* beware of padding in sparc64 timeval */
3609 if (timeval && !in_compat_syscall()) {
3610 struct __kernel_old_timeval __user tv = {
3611 .tv_sec = ts.tv_sec,
3612 .tv_usec = ts.tv_nsec,
3614 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3619 return put_timespec64(&ts, userstamp);
3621 EXPORT_SYMBOL(sock_gettstamp);
3623 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3625 if (!sock_flag(sk, flag)) {
3626 unsigned long previous_flags = sk->sk_flags;
3628 sock_set_flag(sk, flag);
3630 * we just set one of the two flags which require net
3631 * time stamping, but time stamping might have been on
3632 * already because of the other one
3634 if (sock_needs_netstamp(sk) &&
3635 !(previous_flags & SK_FLAGS_TIMESTAMP))
3636 net_enable_timestamp();
3640 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3641 int level, int type)
3643 struct sock_exterr_skb *serr;
3644 struct sk_buff *skb;
3648 skb = sock_dequeue_err_skb(sk);
3654 msg->msg_flags |= MSG_TRUNC;
3657 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3661 sock_recv_timestamp(msg, sk, skb);
3663 serr = SKB_EXT_ERR(skb);
3664 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3666 msg->msg_flags |= MSG_ERRQUEUE;
3674 EXPORT_SYMBOL(sock_recv_errqueue);
3677 * Get a socket option on an socket.
3679 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3680 * asynchronous errors should be reported by getsockopt. We assume
3681 * this means if you specify SO_ERROR (otherwise whats the point of it).
3683 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3684 char __user *optval, int __user *optlen)
3686 struct sock *sk = sock->sk;
3688 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3689 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3691 EXPORT_SYMBOL(sock_common_getsockopt);
3693 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3696 struct sock *sk = sock->sk;
3700 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3702 msg->msg_namelen = addr_len;
3705 EXPORT_SYMBOL(sock_common_recvmsg);
3708 * Set socket options on an inet socket.
3710 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3711 sockptr_t optval, unsigned int optlen)
3713 struct sock *sk = sock->sk;
3715 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3716 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3718 EXPORT_SYMBOL(sock_common_setsockopt);
3720 void sk_common_release(struct sock *sk)
3722 if (sk->sk_prot->destroy)
3723 sk->sk_prot->destroy(sk);
3726 * Observation: when sk_common_release is called, processes have
3727 * no access to socket. But net still has.
3728 * Step one, detach it from networking:
3730 * A. Remove from hash tables.
3733 sk->sk_prot->unhash(sk);
3736 * In this point socket cannot receive new packets, but it is possible
3737 * that some packets are in flight because some CPU runs receiver and
3738 * did hash table lookup before we unhashed socket. They will achieve
3739 * receive queue and will be purged by socket destructor.
3741 * Also we still have packets pending on receive queue and probably,
3742 * our own packets waiting in device queues. sock_destroy will drain
3743 * receive queue, but transmitted packets will delay socket destruction
3744 * until the last reference will be released.
3749 xfrm_sk_free_policy(sk);
3753 EXPORT_SYMBOL(sk_common_release);
3755 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3757 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3759 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3760 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3761 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3762 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3763 mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk);
3764 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3765 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3766 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3767 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3770 #ifdef CONFIG_PROC_FS
3771 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3773 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3775 int cpu, idx = prot->inuse_idx;
3778 for_each_possible_cpu(cpu)
3779 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3781 return res >= 0 ? res : 0;
3783 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3785 int sock_inuse_get(struct net *net)
3789 for_each_possible_cpu(cpu)
3790 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3795 EXPORT_SYMBOL_GPL(sock_inuse_get);
3797 static int __net_init sock_inuse_init_net(struct net *net)
3799 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3800 if (net->core.prot_inuse == NULL)
3805 static void __net_exit sock_inuse_exit_net(struct net *net)
3807 free_percpu(net->core.prot_inuse);
3810 static struct pernet_operations net_inuse_ops = {
3811 .init = sock_inuse_init_net,
3812 .exit = sock_inuse_exit_net,
3815 static __init int net_inuse_init(void)
3817 if (register_pernet_subsys(&net_inuse_ops))
3818 panic("Cannot initialize net inuse counters");
3823 core_initcall(net_inuse_init);
3825 static int assign_proto_idx(struct proto *prot)
3827 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3829 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3830 pr_err("PROTO_INUSE_NR exhausted\n");
3834 set_bit(prot->inuse_idx, proto_inuse_idx);
3838 static void release_proto_idx(struct proto *prot)
3840 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3841 clear_bit(prot->inuse_idx, proto_inuse_idx);
3844 static inline int assign_proto_idx(struct proto *prot)
3849 static inline void release_proto_idx(struct proto *prot)
3855 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3859 kfree(twsk_prot->twsk_slab_name);
3860 twsk_prot->twsk_slab_name = NULL;
3861 kmem_cache_destroy(twsk_prot->twsk_slab);
3862 twsk_prot->twsk_slab = NULL;
3865 static int tw_prot_init(const struct proto *prot)
3867 struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3872 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3874 if (!twsk_prot->twsk_slab_name)
3877 twsk_prot->twsk_slab =
3878 kmem_cache_create(twsk_prot->twsk_slab_name,
3879 twsk_prot->twsk_obj_size, 0,
3880 SLAB_ACCOUNT | prot->slab_flags,
3882 if (!twsk_prot->twsk_slab) {
3883 pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3891 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3895 kfree(rsk_prot->slab_name);
3896 rsk_prot->slab_name = NULL;
3897 kmem_cache_destroy(rsk_prot->slab);
3898 rsk_prot->slab = NULL;
3901 static int req_prot_init(const struct proto *prot)
3903 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3908 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3910 if (!rsk_prot->slab_name)
3913 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3914 rsk_prot->obj_size, 0,
3915 SLAB_ACCOUNT | prot->slab_flags,
3918 if (!rsk_prot->slab) {
3919 pr_crit("%s: Can't create request sock SLAB cache!\n",
3926 int proto_register(struct proto *prot, int alloc_slab)
3930 if (prot->memory_allocated && !prot->sysctl_mem) {
3931 pr_err("%s: missing sysctl_mem\n", prot->name);
3934 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3935 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3939 prot->slab = kmem_cache_create_usercopy(prot->name,
3941 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3943 prot->useroffset, prot->usersize,
3946 if (prot->slab == NULL) {
3947 pr_crit("%s: Can't create sock SLAB cache!\n",
3952 if (req_prot_init(prot))
3953 goto out_free_request_sock_slab;
3955 if (tw_prot_init(prot))
3956 goto out_free_timewait_sock_slab;
3959 mutex_lock(&proto_list_mutex);
3960 ret = assign_proto_idx(prot);
3962 mutex_unlock(&proto_list_mutex);
3963 goto out_free_timewait_sock_slab;
3965 list_add(&prot->node, &proto_list);
3966 mutex_unlock(&proto_list_mutex);
3969 out_free_timewait_sock_slab:
3971 tw_prot_cleanup(prot->twsk_prot);
3972 out_free_request_sock_slab:
3974 req_prot_cleanup(prot->rsk_prot);
3976 kmem_cache_destroy(prot->slab);
3982 EXPORT_SYMBOL(proto_register);
3984 void proto_unregister(struct proto *prot)
3986 mutex_lock(&proto_list_mutex);
3987 release_proto_idx(prot);
3988 list_del(&prot->node);
3989 mutex_unlock(&proto_list_mutex);
3991 kmem_cache_destroy(prot->slab);
3994 req_prot_cleanup(prot->rsk_prot);
3995 tw_prot_cleanup(prot->twsk_prot);
3997 EXPORT_SYMBOL(proto_unregister);
3999 int sock_load_diag_module(int family, int protocol)
4002 if (!sock_is_registered(family))
4005 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4006 NETLINK_SOCK_DIAG, family);
4010 if (family == AF_INET &&
4011 protocol != IPPROTO_RAW &&
4012 protocol < MAX_INET_PROTOS &&
4013 !rcu_access_pointer(inet_protos[protocol]))
4017 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4018 NETLINK_SOCK_DIAG, family, protocol);
4020 EXPORT_SYMBOL(sock_load_diag_module);
4022 #ifdef CONFIG_PROC_FS
4023 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4024 __acquires(proto_list_mutex)
4026 mutex_lock(&proto_list_mutex);
4027 return seq_list_start_head(&proto_list, *pos);
4030 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4032 return seq_list_next(v, &proto_list, pos);
4035 static void proto_seq_stop(struct seq_file *seq, void *v)
4036 __releases(proto_list_mutex)
4038 mutex_unlock(&proto_list_mutex);
4041 static char proto_method_implemented(const void *method)
4043 return method == NULL ? 'n' : 'y';
4045 static long sock_prot_memory_allocated(struct proto *proto)
4047 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4050 static const char *sock_prot_memory_pressure(struct proto *proto)
4052 return proto->memory_pressure != NULL ?
4053 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4056 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4059 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
4060 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4063 sock_prot_inuse_get(seq_file_net(seq), proto),
4064 sock_prot_memory_allocated(proto),
4065 sock_prot_memory_pressure(proto),
4067 proto->slab == NULL ? "no" : "yes",
4068 module_name(proto->owner),
4069 proto_method_implemented(proto->close),
4070 proto_method_implemented(proto->connect),
4071 proto_method_implemented(proto->disconnect),
4072 proto_method_implemented(proto->accept),
4073 proto_method_implemented(proto->ioctl),
4074 proto_method_implemented(proto->init),
4075 proto_method_implemented(proto->destroy),
4076 proto_method_implemented(proto->shutdown),
4077 proto_method_implemented(proto->setsockopt),
4078 proto_method_implemented(proto->getsockopt),
4079 proto_method_implemented(proto->sendmsg),
4080 proto_method_implemented(proto->recvmsg),
4081 proto_method_implemented(proto->bind),
4082 proto_method_implemented(proto->backlog_rcv),
4083 proto_method_implemented(proto->hash),
4084 proto_method_implemented(proto->unhash),
4085 proto_method_implemented(proto->get_port),
4086 proto_method_implemented(proto->enter_memory_pressure));
4089 static int proto_seq_show(struct seq_file *seq, void *v)
4091 if (v == &proto_list)
4092 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4101 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4103 proto_seq_printf(seq, list_entry(v, struct proto, node));
4107 static const struct seq_operations proto_seq_ops = {
4108 .start = proto_seq_start,
4109 .next = proto_seq_next,
4110 .stop = proto_seq_stop,
4111 .show = proto_seq_show,
4114 static __net_init int proto_init_net(struct net *net)
4116 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4117 sizeof(struct seq_net_private)))
4123 static __net_exit void proto_exit_net(struct net *net)
4125 remove_proc_entry("protocols", net->proc_net);
4129 static __net_initdata struct pernet_operations proto_net_ops = {
4130 .init = proto_init_net,
4131 .exit = proto_exit_net,
4134 static int __init proto_init(void)
4136 return register_pernet_subsys(&proto_net_ops);
4139 subsys_initcall(proto_init);
4141 #endif /* PROC_FS */
4143 #ifdef CONFIG_NET_RX_BUSY_POLL
4144 bool sk_busy_loop_end(void *p, unsigned long start_time)
4146 struct sock *sk = p;
4148 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4151 if (sk_is_udp(sk) &&
4152 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4155 return sk_busy_loop_timeout(sk, start_time);
4157 EXPORT_SYMBOL(sk_busy_loop_end);
4158 #endif /* CONFIG_NET_RX_BUSY_POLL */
4160 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4162 if (!sk->sk_prot->bind_add)
4164 return sk->sk_prot->bind_add(sk, addr, addr_len);
4166 EXPORT_SYMBOL(sock_bind_add);
4168 /* Copy 'size' bytes from userspace and return `size` back to userspace */
4169 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4170 void __user *arg, void *karg, size_t size)
4174 if (copy_from_user(karg, arg, size))
4177 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4181 if (copy_to_user(arg, karg, size))
4186 EXPORT_SYMBOL(sock_ioctl_inout);
4188 /* This is the most common ioctl prep function, where the result (4 bytes) is
4189 * copied back to userspace if the ioctl() returns successfully. No input is
4190 * copied from userspace as input argument.
4192 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4196 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4200 return put_user(karg, (int __user *)arg);
4203 /* A wrapper around sock ioctls, which copies the data from userspace
4204 * (depending on the protocol/ioctl), and copies back the result to userspace.
4205 * The main motivation for this function is to pass kernel memory to the
4206 * protocol ioctl callbacks, instead of userspace memory.
4208 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4212 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4213 rc = ipmr_sk_ioctl(sk, cmd, arg);
4214 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4215 rc = ip6mr_sk_ioctl(sk, cmd, arg);
4216 else if (sk_is_phonet(sk))
4217 rc = phonet_sk_ioctl(sk, cmd, arg);
4219 /* If ioctl was processed, returns its value */
4223 /* Otherwise call the default handler */
4224 return sock_ioctl_out(sk, cmd, arg);
4226 EXPORT_SYMBOL(sk_ioctl);