rtnetlink: check DO_SETLINK_NOTIFY correctly in do_setlink
[linux/fpc-iii.git] / net / core / sock.c
blob415f441c63b9e2ff8feb010f44ca27303c72aaa1
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
10 * Authors: Ross Biro
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>
15 * Fixes:
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
36 * TCP layer surgery.
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
64 * (compatibility fix)
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
83 * To Fix:
86 * This program is free software; you can redistribute it and/or
87 * modify it under the terms of the GNU General Public License
88 * as published by the Free Software Foundation; either version
89 * 2 of the License, or (at your option) any later version.
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/errqueue.h>
97 #include <linux/types.h>
98 #include <linux/socket.h>
99 #include <linux/in.h>
100 #include <linux/kernel.h>
101 #include <linux/module.h>
102 #include <linux/proc_fs.h>
103 #include <linux/seq_file.h>
104 #include <linux/sched.h>
105 #include <linux/sched/mm.h>
106 #include <linux/timer.h>
107 #include <linux/string.h>
108 #include <linux/sockios.h>
109 #include <linux/net.h>
110 #include <linux/mm.h>
111 #include <linux/slab.h>
112 #include <linux/interrupt.h>
113 #include <linux/poll.h>
114 #include <linux/tcp.h>
115 #include <linux/init.h>
116 #include <linux/highmem.h>
117 #include <linux/user_namespace.h>
118 #include <linux/static_key.h>
119 #include <linux/memcontrol.h>
120 #include <linux/prefetch.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>
140 #include <trace/events/sock.h>
142 #include <net/tcp.h>
143 #include <net/busy_poll.h>
145 static DEFINE_MUTEX(proto_list_mutex);
146 static LIST_HEAD(proto_list);
149 * sk_ns_capable - General socket capability test
150 * @sk: Socket to use a capability on or through
151 * @user_ns: The user namespace of the capability to use
152 * @cap: The capability to use
154 * Test to see if the opener of the socket had when the socket was
155 * created and the current process has the capability @cap in the user
156 * namespace @user_ns.
158 bool sk_ns_capable(const struct sock *sk,
159 struct user_namespace *user_ns, int cap)
161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
162 ns_capable(user_ns, cap);
164 EXPORT_SYMBOL(sk_ns_capable);
167 * sk_capable - Socket global capability test
168 * @sk: Socket to use a capability on or through
169 * @cap: The global capability to use
171 * Test to see if the opener of the socket had when the socket was
172 * created and the current process has the capability @cap in all user
173 * namespaces.
175 bool sk_capable(const struct sock *sk, int cap)
177 return sk_ns_capable(sk, &init_user_ns, cap);
179 EXPORT_SYMBOL(sk_capable);
182 * sk_net_capable - Network namespace socket capability test
183 * @sk: Socket to use a capability on or through
184 * @cap: The capability to use
186 * Test to see if the opener of the socket had when the socket was created
187 * and the current process has the capability @cap over the network namespace
188 * the socket is a member of.
190 bool sk_net_capable(const struct sock *sk, int cap)
192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
194 EXPORT_SYMBOL(sk_net_capable);
197 * Each address family might have different locking rules, so we have
198 * one slock key per address family and separate keys for internal and
199 * userspace sockets.
201 static struct lock_class_key af_family_keys[AF_MAX];
202 static struct lock_class_key af_family_kern_keys[AF_MAX];
203 static struct lock_class_key af_family_slock_keys[AF_MAX];
204 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
207 * Make lock validator output more readable. (we pre-construct these
208 * strings build-time, so that runtime initialization of socket
209 * locks is fast):
212 #define _sock_locks(x) \
213 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
214 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
215 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
216 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
217 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
218 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
219 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
220 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
221 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
222 x "27" , x "28" , x "AF_CAN" , \
223 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
224 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
225 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
226 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
227 x "AF_QIPCRTR", x "AF_SMC" , x "AF_MAX"
229 static const char *const af_family_key_strings[AF_MAX+1] = {
230 _sock_locks("sk_lock-")
232 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
233 _sock_locks("slock-")
235 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
236 _sock_locks("clock-")
239 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
240 _sock_locks("k-sk_lock-")
242 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
243 _sock_locks("k-slock-")
245 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
246 _sock_locks("k-clock-")
248 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
249 "rlock-AF_UNSPEC", "rlock-AF_UNIX" , "rlock-AF_INET" ,
250 "rlock-AF_AX25" , "rlock-AF_IPX" , "rlock-AF_APPLETALK",
251 "rlock-AF_NETROM", "rlock-AF_BRIDGE" , "rlock-AF_ATMPVC" ,
252 "rlock-AF_X25" , "rlock-AF_INET6" , "rlock-AF_ROSE" ,
253 "rlock-AF_DECnet", "rlock-AF_NETBEUI" , "rlock-AF_SECURITY" ,
254 "rlock-AF_KEY" , "rlock-AF_NETLINK" , "rlock-AF_PACKET" ,
255 "rlock-AF_ASH" , "rlock-AF_ECONET" , "rlock-AF_ATMSVC" ,
256 "rlock-AF_RDS" , "rlock-AF_SNA" , "rlock-AF_IRDA" ,
257 "rlock-AF_PPPOX" , "rlock-AF_WANPIPE" , "rlock-AF_LLC" ,
258 "rlock-27" , "rlock-28" , "rlock-AF_CAN" ,
259 "rlock-AF_TIPC" , "rlock-AF_BLUETOOTH", "rlock-AF_IUCV" ,
260 "rlock-AF_RXRPC" , "rlock-AF_ISDN" , "rlock-AF_PHONET" ,
261 "rlock-AF_IEEE802154", "rlock-AF_CAIF" , "rlock-AF_ALG" ,
262 "rlock-AF_NFC" , "rlock-AF_VSOCK" , "rlock-AF_KCM" ,
263 "rlock-AF_QIPCRTR", "rlock-AF_SMC" , "rlock-AF_MAX"
265 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
266 "wlock-AF_UNSPEC", "wlock-AF_UNIX" , "wlock-AF_INET" ,
267 "wlock-AF_AX25" , "wlock-AF_IPX" , "wlock-AF_APPLETALK",
268 "wlock-AF_NETROM", "wlock-AF_BRIDGE" , "wlock-AF_ATMPVC" ,
269 "wlock-AF_X25" , "wlock-AF_INET6" , "wlock-AF_ROSE" ,
270 "wlock-AF_DECnet", "wlock-AF_NETBEUI" , "wlock-AF_SECURITY" ,
271 "wlock-AF_KEY" , "wlock-AF_NETLINK" , "wlock-AF_PACKET" ,
272 "wlock-AF_ASH" , "wlock-AF_ECONET" , "wlock-AF_ATMSVC" ,
273 "wlock-AF_RDS" , "wlock-AF_SNA" , "wlock-AF_IRDA" ,
274 "wlock-AF_PPPOX" , "wlock-AF_WANPIPE" , "wlock-AF_LLC" ,
275 "wlock-27" , "wlock-28" , "wlock-AF_CAN" ,
276 "wlock-AF_TIPC" , "wlock-AF_BLUETOOTH", "wlock-AF_IUCV" ,
277 "wlock-AF_RXRPC" , "wlock-AF_ISDN" , "wlock-AF_PHONET" ,
278 "wlock-AF_IEEE802154", "wlock-AF_CAIF" , "wlock-AF_ALG" ,
279 "wlock-AF_NFC" , "wlock-AF_VSOCK" , "wlock-AF_KCM" ,
280 "wlock-AF_QIPCRTR", "wlock-AF_SMC" , "wlock-AF_MAX"
282 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
283 "elock-AF_UNSPEC", "elock-AF_UNIX" , "elock-AF_INET" ,
284 "elock-AF_AX25" , "elock-AF_IPX" , "elock-AF_APPLETALK",
285 "elock-AF_NETROM", "elock-AF_BRIDGE" , "elock-AF_ATMPVC" ,
286 "elock-AF_X25" , "elock-AF_INET6" , "elock-AF_ROSE" ,
287 "elock-AF_DECnet", "elock-AF_NETBEUI" , "elock-AF_SECURITY" ,
288 "elock-AF_KEY" , "elock-AF_NETLINK" , "elock-AF_PACKET" ,
289 "elock-AF_ASH" , "elock-AF_ECONET" , "elock-AF_ATMSVC" ,
290 "elock-AF_RDS" , "elock-AF_SNA" , "elock-AF_IRDA" ,
291 "elock-AF_PPPOX" , "elock-AF_WANPIPE" , "elock-AF_LLC" ,
292 "elock-27" , "elock-28" , "elock-AF_CAN" ,
293 "elock-AF_TIPC" , "elock-AF_BLUETOOTH", "elock-AF_IUCV" ,
294 "elock-AF_RXRPC" , "elock-AF_ISDN" , "elock-AF_PHONET" ,
295 "elock-AF_IEEE802154", "elock-AF_CAIF" , "elock-AF_ALG" ,
296 "elock-AF_NFC" , "elock-AF_VSOCK" , "elock-AF_KCM" ,
297 "elock-AF_QIPCRTR", "elock-AF_SMC" , "elock-AF_MAX"
301 * sk_callback_lock and sk queues locking rules are per-address-family,
302 * so split the lock classes by using a per-AF key:
304 static struct lock_class_key af_callback_keys[AF_MAX];
305 static struct lock_class_key af_rlock_keys[AF_MAX];
306 static struct lock_class_key af_wlock_keys[AF_MAX];
307 static struct lock_class_key af_elock_keys[AF_MAX];
308 static struct lock_class_key af_kern_callback_keys[AF_MAX];
310 /* Run time adjustable parameters. */
311 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
312 EXPORT_SYMBOL(sysctl_wmem_max);
313 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
314 EXPORT_SYMBOL(sysctl_rmem_max);
315 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
316 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
318 /* Maximal space eaten by iovec or ancillary data plus some space */
319 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
320 EXPORT_SYMBOL(sysctl_optmem_max);
322 int sysctl_tstamp_allow_data __read_mostly = 1;
324 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
325 EXPORT_SYMBOL_GPL(memalloc_socks);
328 * sk_set_memalloc - sets %SOCK_MEMALLOC
329 * @sk: socket to set it on
331 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
332 * It's the responsibility of the admin to adjust min_free_kbytes
333 * to meet the requirements
335 void sk_set_memalloc(struct sock *sk)
337 sock_set_flag(sk, SOCK_MEMALLOC);
338 sk->sk_allocation |= __GFP_MEMALLOC;
339 static_key_slow_inc(&memalloc_socks);
341 EXPORT_SYMBOL_GPL(sk_set_memalloc);
343 void sk_clear_memalloc(struct sock *sk)
345 sock_reset_flag(sk, SOCK_MEMALLOC);
346 sk->sk_allocation &= ~__GFP_MEMALLOC;
347 static_key_slow_dec(&memalloc_socks);
350 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
351 * progress of swapping. SOCK_MEMALLOC may be cleared while
352 * it has rmem allocations due to the last swapfile being deactivated
353 * but there is a risk that the socket is unusable due to exceeding
354 * the rmem limits. Reclaim the reserves and obey rmem limits again.
356 sk_mem_reclaim(sk);
358 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
360 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
362 int ret;
363 unsigned int noreclaim_flag;
365 /* these should have been dropped before queueing */
366 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
368 noreclaim_flag = memalloc_noreclaim_save();
369 ret = sk->sk_backlog_rcv(sk, skb);
370 memalloc_noreclaim_restore(noreclaim_flag);
372 return ret;
374 EXPORT_SYMBOL(__sk_backlog_rcv);
376 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
378 struct timeval tv;
380 if (optlen < sizeof(tv))
381 return -EINVAL;
382 if (copy_from_user(&tv, optval, sizeof(tv)))
383 return -EFAULT;
384 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
385 return -EDOM;
387 if (tv.tv_sec < 0) {
388 static int warned __read_mostly;
390 *timeo_p = 0;
391 if (warned < 10 && net_ratelimit()) {
392 warned++;
393 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
394 __func__, current->comm, task_pid_nr(current));
396 return 0;
398 *timeo_p = MAX_SCHEDULE_TIMEOUT;
399 if (tv.tv_sec == 0 && tv.tv_usec == 0)
400 return 0;
401 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
402 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ);
403 return 0;
406 static void sock_warn_obsolete_bsdism(const char *name)
408 static int warned;
409 static char warncomm[TASK_COMM_LEN];
410 if (strcmp(warncomm, current->comm) && warned < 5) {
411 strcpy(warncomm, current->comm);
412 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
413 warncomm, name);
414 warned++;
418 static bool sock_needs_netstamp(const struct sock *sk)
420 switch (sk->sk_family) {
421 case AF_UNSPEC:
422 case AF_UNIX:
423 return false;
424 default:
425 return true;
429 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
431 if (sk->sk_flags & flags) {
432 sk->sk_flags &= ~flags;
433 if (sock_needs_netstamp(sk) &&
434 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
435 net_disable_timestamp();
440 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
442 unsigned long flags;
443 struct sk_buff_head *list = &sk->sk_receive_queue;
445 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
446 atomic_inc(&sk->sk_drops);
447 trace_sock_rcvqueue_full(sk, skb);
448 return -ENOMEM;
451 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
452 atomic_inc(&sk->sk_drops);
453 return -ENOBUFS;
456 skb->dev = NULL;
457 skb_set_owner_r(skb, sk);
459 /* we escape from rcu protected region, make sure we dont leak
460 * a norefcounted dst
462 skb_dst_force(skb);
464 spin_lock_irqsave(&list->lock, flags);
465 sock_skb_set_dropcount(sk, skb);
466 __skb_queue_tail(list, skb);
467 spin_unlock_irqrestore(&list->lock, flags);
469 if (!sock_flag(sk, SOCK_DEAD))
470 sk->sk_data_ready(sk);
471 return 0;
473 EXPORT_SYMBOL(__sock_queue_rcv_skb);
475 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 int err;
479 err = sk_filter(sk, skb);
480 if (err)
481 return err;
483 return __sock_queue_rcv_skb(sk, skb);
485 EXPORT_SYMBOL(sock_queue_rcv_skb);
487 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
488 const int nested, unsigned int trim_cap, bool refcounted)
490 int rc = NET_RX_SUCCESS;
492 if (sk_filter_trim_cap(sk, skb, trim_cap))
493 goto discard_and_relse;
495 skb->dev = NULL;
497 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
498 atomic_inc(&sk->sk_drops);
499 goto discard_and_relse;
501 if (nested)
502 bh_lock_sock_nested(sk);
503 else
504 bh_lock_sock(sk);
505 if (!sock_owned_by_user(sk)) {
507 * trylock + unlock semantics:
509 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
511 rc = sk_backlog_rcv(sk, skb);
513 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
514 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
515 bh_unlock_sock(sk);
516 atomic_inc(&sk->sk_drops);
517 goto discard_and_relse;
520 bh_unlock_sock(sk);
521 out:
522 if (refcounted)
523 sock_put(sk);
524 return rc;
525 discard_and_relse:
526 kfree_skb(skb);
527 goto out;
529 EXPORT_SYMBOL(__sk_receive_skb);
531 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
533 struct dst_entry *dst = __sk_dst_get(sk);
535 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
536 sk_tx_queue_clear(sk);
537 sk->sk_dst_pending_confirm = 0;
538 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
539 dst_release(dst);
540 return NULL;
543 return dst;
545 EXPORT_SYMBOL(__sk_dst_check);
547 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
549 struct dst_entry *dst = sk_dst_get(sk);
551 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
552 sk_dst_reset(sk);
553 dst_release(dst);
554 return NULL;
557 return dst;
559 EXPORT_SYMBOL(sk_dst_check);
561 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
562 int optlen)
564 int ret = -ENOPROTOOPT;
565 #ifdef CONFIG_NETDEVICES
566 struct net *net = sock_net(sk);
567 char devname[IFNAMSIZ];
568 int index;
570 /* Sorry... */
571 ret = -EPERM;
572 if (!ns_capable(net->user_ns, CAP_NET_RAW))
573 goto out;
575 ret = -EINVAL;
576 if (optlen < 0)
577 goto out;
579 /* Bind this socket to a particular device like "eth0",
580 * as specified in the passed interface name. If the
581 * name is "" or the option length is zero the socket
582 * is not bound.
584 if (optlen > IFNAMSIZ - 1)
585 optlen = IFNAMSIZ - 1;
586 memset(devname, 0, sizeof(devname));
588 ret = -EFAULT;
589 if (copy_from_user(devname, optval, optlen))
590 goto out;
592 index = 0;
593 if (devname[0] != '\0') {
594 struct net_device *dev;
596 rcu_read_lock();
597 dev = dev_get_by_name_rcu(net, devname);
598 if (dev)
599 index = dev->ifindex;
600 rcu_read_unlock();
601 ret = -ENODEV;
602 if (!dev)
603 goto out;
606 lock_sock(sk);
607 sk->sk_bound_dev_if = index;
608 sk_dst_reset(sk);
609 release_sock(sk);
611 ret = 0;
613 out:
614 #endif
616 return ret;
619 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
620 int __user *optlen, int len)
622 int ret = -ENOPROTOOPT;
623 #ifdef CONFIG_NETDEVICES
624 struct net *net = sock_net(sk);
625 char devname[IFNAMSIZ];
627 if (sk->sk_bound_dev_if == 0) {
628 len = 0;
629 goto zero;
632 ret = -EINVAL;
633 if (len < IFNAMSIZ)
634 goto out;
636 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
637 if (ret)
638 goto out;
640 len = strlen(devname) + 1;
642 ret = -EFAULT;
643 if (copy_to_user(optval, devname, len))
644 goto out;
646 zero:
647 ret = -EFAULT;
648 if (put_user(len, optlen))
649 goto out;
651 ret = 0;
653 out:
654 #endif
656 return ret;
659 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
661 if (valbool)
662 sock_set_flag(sk, bit);
663 else
664 sock_reset_flag(sk, bit);
667 bool sk_mc_loop(struct sock *sk)
669 if (dev_recursion_level())
670 return false;
671 if (!sk)
672 return true;
673 switch (sk->sk_family) {
674 case AF_INET:
675 return inet_sk(sk)->mc_loop;
676 #if IS_ENABLED(CONFIG_IPV6)
677 case AF_INET6:
678 return inet6_sk(sk)->mc_loop;
679 #endif
681 WARN_ON(1);
682 return true;
684 EXPORT_SYMBOL(sk_mc_loop);
687 * This is meant for all protocols to use and covers goings on
688 * at the socket level. Everything here is generic.
691 int sock_setsockopt(struct socket *sock, int level, int optname,
692 char __user *optval, unsigned int optlen)
694 struct sock *sk = sock->sk;
695 int val;
696 int valbool;
697 struct linger ling;
698 int ret = 0;
701 * Options without arguments
704 if (optname == SO_BINDTODEVICE)
705 return sock_setbindtodevice(sk, optval, optlen);
707 if (optlen < sizeof(int))
708 return -EINVAL;
710 if (get_user(val, (int __user *)optval))
711 return -EFAULT;
713 valbool = val ? 1 : 0;
715 lock_sock(sk);
717 switch (optname) {
718 case SO_DEBUG:
719 if (val && !capable(CAP_NET_ADMIN))
720 ret = -EACCES;
721 else
722 sock_valbool_flag(sk, SOCK_DBG, valbool);
723 break;
724 case SO_REUSEADDR:
725 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
726 break;
727 case SO_REUSEPORT:
728 sk->sk_reuseport = valbool;
729 break;
730 case SO_TYPE:
731 case SO_PROTOCOL:
732 case SO_DOMAIN:
733 case SO_ERROR:
734 ret = -ENOPROTOOPT;
735 break;
736 case SO_DONTROUTE:
737 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
738 break;
739 case SO_BROADCAST:
740 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
741 break;
742 case SO_SNDBUF:
743 /* Don't error on this BSD doesn't and if you think
744 * about it this is right. Otherwise apps have to
745 * play 'guess the biggest size' games. RCVBUF/SNDBUF
746 * are treated in BSD as hints
748 val = min_t(u32, val, sysctl_wmem_max);
749 set_sndbuf:
750 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
751 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
752 /* Wake up sending tasks if we upped the value. */
753 sk->sk_write_space(sk);
754 break;
756 case SO_SNDBUFFORCE:
757 if (!capable(CAP_NET_ADMIN)) {
758 ret = -EPERM;
759 break;
761 goto set_sndbuf;
763 case SO_RCVBUF:
764 /* Don't error on this BSD doesn't and if you think
765 * about it this is right. Otherwise apps have to
766 * play 'guess the biggest size' games. RCVBUF/SNDBUF
767 * are treated in BSD as hints
769 val = min_t(u32, val, sysctl_rmem_max);
770 set_rcvbuf:
771 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
773 * We double it on the way in to account for
774 * "struct sk_buff" etc. overhead. Applications
775 * assume that the SO_RCVBUF setting they make will
776 * allow that much actual data to be received on that
777 * socket.
779 * Applications are unaware that "struct sk_buff" and
780 * other overheads allocate from the receive buffer
781 * during socket buffer allocation.
783 * And after considering the possible alternatives,
784 * returning the value we actually used in getsockopt
785 * is the most desirable behavior.
787 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
788 break;
790 case SO_RCVBUFFORCE:
791 if (!capable(CAP_NET_ADMIN)) {
792 ret = -EPERM;
793 break;
795 goto set_rcvbuf;
797 case SO_KEEPALIVE:
798 if (sk->sk_prot->keepalive)
799 sk->sk_prot->keepalive(sk, valbool);
800 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
801 break;
803 case SO_OOBINLINE:
804 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
805 break;
807 case SO_NO_CHECK:
808 sk->sk_no_check_tx = valbool;
809 break;
811 case SO_PRIORITY:
812 if ((val >= 0 && val <= 6) ||
813 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
814 sk->sk_priority = val;
815 else
816 ret = -EPERM;
817 break;
819 case SO_LINGER:
820 if (optlen < sizeof(ling)) {
821 ret = -EINVAL; /* 1003.1g */
822 break;
824 if (copy_from_user(&ling, optval, sizeof(ling))) {
825 ret = -EFAULT;
826 break;
828 if (!ling.l_onoff)
829 sock_reset_flag(sk, SOCK_LINGER);
830 else {
831 #if (BITS_PER_LONG == 32)
832 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
833 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
834 else
835 #endif
836 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
837 sock_set_flag(sk, SOCK_LINGER);
839 break;
841 case SO_BSDCOMPAT:
842 sock_warn_obsolete_bsdism("setsockopt");
843 break;
845 case SO_PASSCRED:
846 if (valbool)
847 set_bit(SOCK_PASSCRED, &sock->flags);
848 else
849 clear_bit(SOCK_PASSCRED, &sock->flags);
850 break;
852 case SO_TIMESTAMP:
853 case SO_TIMESTAMPNS:
854 if (valbool) {
855 if (optname == SO_TIMESTAMP)
856 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
857 else
858 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
859 sock_set_flag(sk, SOCK_RCVTSTAMP);
860 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
861 } else {
862 sock_reset_flag(sk, SOCK_RCVTSTAMP);
863 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
865 break;
867 case SO_TIMESTAMPING:
868 if (val & ~SOF_TIMESTAMPING_MASK) {
869 ret = -EINVAL;
870 break;
873 if (val & SOF_TIMESTAMPING_OPT_ID &&
874 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
875 if (sk->sk_protocol == IPPROTO_TCP &&
876 sk->sk_type == SOCK_STREAM) {
877 if ((1 << sk->sk_state) &
878 (TCPF_CLOSE | TCPF_LISTEN)) {
879 ret = -EINVAL;
880 break;
882 sk->sk_tskey = tcp_sk(sk)->snd_una;
883 } else {
884 sk->sk_tskey = 0;
888 if (val & SOF_TIMESTAMPING_OPT_STATS &&
889 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
890 ret = -EINVAL;
891 break;
894 sk->sk_tsflags = val;
895 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
896 sock_enable_timestamp(sk,
897 SOCK_TIMESTAMPING_RX_SOFTWARE);
898 else
899 sock_disable_timestamp(sk,
900 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
901 break;
903 case SO_RCVLOWAT:
904 if (val < 0)
905 val = INT_MAX;
906 sk->sk_rcvlowat = val ? : 1;
907 break;
909 case SO_RCVTIMEO:
910 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
911 break;
913 case SO_SNDTIMEO:
914 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
915 break;
917 case SO_ATTACH_FILTER:
918 ret = -EINVAL;
919 if (optlen == sizeof(struct sock_fprog)) {
920 struct sock_fprog fprog;
922 ret = -EFAULT;
923 if (copy_from_user(&fprog, optval, sizeof(fprog)))
924 break;
926 ret = sk_attach_filter(&fprog, sk);
928 break;
930 case SO_ATTACH_BPF:
931 ret = -EINVAL;
932 if (optlen == sizeof(u32)) {
933 u32 ufd;
935 ret = -EFAULT;
936 if (copy_from_user(&ufd, optval, sizeof(ufd)))
937 break;
939 ret = sk_attach_bpf(ufd, sk);
941 break;
943 case SO_ATTACH_REUSEPORT_CBPF:
944 ret = -EINVAL;
945 if (optlen == sizeof(struct sock_fprog)) {
946 struct sock_fprog fprog;
948 ret = -EFAULT;
949 if (copy_from_user(&fprog, optval, sizeof(fprog)))
950 break;
952 ret = sk_reuseport_attach_filter(&fprog, sk);
954 break;
956 case SO_ATTACH_REUSEPORT_EBPF:
957 ret = -EINVAL;
958 if (optlen == sizeof(u32)) {
959 u32 ufd;
961 ret = -EFAULT;
962 if (copy_from_user(&ufd, optval, sizeof(ufd)))
963 break;
965 ret = sk_reuseport_attach_bpf(ufd, sk);
967 break;
969 case SO_DETACH_FILTER:
970 ret = sk_detach_filter(sk);
971 break;
973 case SO_LOCK_FILTER:
974 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
975 ret = -EPERM;
976 else
977 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
978 break;
980 case SO_PASSSEC:
981 if (valbool)
982 set_bit(SOCK_PASSSEC, &sock->flags);
983 else
984 clear_bit(SOCK_PASSSEC, &sock->flags);
985 break;
986 case SO_MARK:
987 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
988 ret = -EPERM;
989 else
990 sk->sk_mark = val;
991 break;
993 case SO_RXQ_OVFL:
994 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
995 break;
997 case SO_WIFI_STATUS:
998 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
999 break;
1001 case SO_PEEK_OFF:
1002 if (sock->ops->set_peek_off)
1003 ret = sock->ops->set_peek_off(sk, val);
1004 else
1005 ret = -EOPNOTSUPP;
1006 break;
1008 case SO_NOFCS:
1009 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1010 break;
1012 case SO_SELECT_ERR_QUEUE:
1013 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1014 break;
1016 #ifdef CONFIG_NET_RX_BUSY_POLL
1017 case SO_BUSY_POLL:
1018 /* allow unprivileged users to decrease the value */
1019 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1020 ret = -EPERM;
1021 else {
1022 if (val < 0)
1023 ret = -EINVAL;
1024 else
1025 sk->sk_ll_usec = val;
1027 break;
1028 #endif
1030 case SO_MAX_PACING_RATE:
1031 if (val != ~0U)
1032 cmpxchg(&sk->sk_pacing_status,
1033 SK_PACING_NONE,
1034 SK_PACING_NEEDED);
1035 sk->sk_max_pacing_rate = val;
1036 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1037 sk->sk_max_pacing_rate);
1038 break;
1040 case SO_INCOMING_CPU:
1041 sk->sk_incoming_cpu = val;
1042 break;
1044 case SO_CNX_ADVICE:
1045 if (val == 1)
1046 dst_negative_advice(sk);
1047 break;
1049 case SO_ZEROCOPY:
1050 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
1051 ret = -ENOTSUPP;
1052 else if (sk->sk_protocol != IPPROTO_TCP)
1053 ret = -ENOTSUPP;
1054 else if (sk->sk_state != TCP_CLOSE)
1055 ret = -EBUSY;
1056 else if (val < 0 || val > 1)
1057 ret = -EINVAL;
1058 else
1059 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1060 break;
1062 default:
1063 ret = -ENOPROTOOPT;
1064 break;
1066 release_sock(sk);
1067 return ret;
1069 EXPORT_SYMBOL(sock_setsockopt);
1072 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1073 struct ucred *ucred)
1075 ucred->pid = pid_vnr(pid);
1076 ucred->uid = ucred->gid = -1;
1077 if (cred) {
1078 struct user_namespace *current_ns = current_user_ns();
1080 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1081 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1085 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1087 struct user_namespace *user_ns = current_user_ns();
1088 int i;
1090 for (i = 0; i < src->ngroups; i++)
1091 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1092 return -EFAULT;
1094 return 0;
1097 int sock_getsockopt(struct socket *sock, int level, int optname,
1098 char __user *optval, int __user *optlen)
1100 struct sock *sk = sock->sk;
1102 union {
1103 int val;
1104 u64 val64;
1105 struct linger ling;
1106 struct timeval tm;
1107 } v;
1109 int lv = sizeof(int);
1110 int len;
1112 if (get_user(len, optlen))
1113 return -EFAULT;
1114 if (len < 0)
1115 return -EINVAL;
1117 memset(&v, 0, sizeof(v));
1119 switch (optname) {
1120 case SO_DEBUG:
1121 v.val = sock_flag(sk, SOCK_DBG);
1122 break;
1124 case SO_DONTROUTE:
1125 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1126 break;
1128 case SO_BROADCAST:
1129 v.val = sock_flag(sk, SOCK_BROADCAST);
1130 break;
1132 case SO_SNDBUF:
1133 v.val = sk->sk_sndbuf;
1134 break;
1136 case SO_RCVBUF:
1137 v.val = sk->sk_rcvbuf;
1138 break;
1140 case SO_REUSEADDR:
1141 v.val = sk->sk_reuse;
1142 break;
1144 case SO_REUSEPORT:
1145 v.val = sk->sk_reuseport;
1146 break;
1148 case SO_KEEPALIVE:
1149 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1150 break;
1152 case SO_TYPE:
1153 v.val = sk->sk_type;
1154 break;
1156 case SO_PROTOCOL:
1157 v.val = sk->sk_protocol;
1158 break;
1160 case SO_DOMAIN:
1161 v.val = sk->sk_family;
1162 break;
1164 case SO_ERROR:
1165 v.val = -sock_error(sk);
1166 if (v.val == 0)
1167 v.val = xchg(&sk->sk_err_soft, 0);
1168 break;
1170 case SO_OOBINLINE:
1171 v.val = sock_flag(sk, SOCK_URGINLINE);
1172 break;
1174 case SO_NO_CHECK:
1175 v.val = sk->sk_no_check_tx;
1176 break;
1178 case SO_PRIORITY:
1179 v.val = sk->sk_priority;
1180 break;
1182 case SO_LINGER:
1183 lv = sizeof(v.ling);
1184 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1185 v.ling.l_linger = sk->sk_lingertime / HZ;
1186 break;
1188 case SO_BSDCOMPAT:
1189 sock_warn_obsolete_bsdism("getsockopt");
1190 break;
1192 case SO_TIMESTAMP:
1193 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1194 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1195 break;
1197 case SO_TIMESTAMPNS:
1198 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1199 break;
1201 case SO_TIMESTAMPING:
1202 v.val = sk->sk_tsflags;
1203 break;
1205 case SO_RCVTIMEO:
1206 lv = sizeof(struct timeval);
1207 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1208 v.tm.tv_sec = 0;
1209 v.tm.tv_usec = 0;
1210 } else {
1211 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1212 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
1214 break;
1216 case SO_SNDTIMEO:
1217 lv = sizeof(struct timeval);
1218 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1219 v.tm.tv_sec = 0;
1220 v.tm.tv_usec = 0;
1221 } else {
1222 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1223 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1225 break;
1227 case SO_RCVLOWAT:
1228 v.val = sk->sk_rcvlowat;
1229 break;
1231 case SO_SNDLOWAT:
1232 v.val = 1;
1233 break;
1235 case SO_PASSCRED:
1236 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1237 break;
1239 case SO_PEERCRED:
1241 struct ucred peercred;
1242 if (len > sizeof(peercred))
1243 len = sizeof(peercred);
1244 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1245 if (copy_to_user(optval, &peercred, len))
1246 return -EFAULT;
1247 goto lenout;
1250 case SO_PEERGROUPS:
1252 int ret, n;
1254 if (!sk->sk_peer_cred)
1255 return -ENODATA;
1257 n = sk->sk_peer_cred->group_info->ngroups;
1258 if (len < n * sizeof(gid_t)) {
1259 len = n * sizeof(gid_t);
1260 return put_user(len, optlen) ? -EFAULT : -ERANGE;
1262 len = n * sizeof(gid_t);
1264 ret = groups_to_user((gid_t __user *)optval,
1265 sk->sk_peer_cred->group_info);
1266 if (ret)
1267 return ret;
1268 goto lenout;
1271 case SO_PEERNAME:
1273 char address[128];
1275 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1276 return -ENOTCONN;
1277 if (lv < len)
1278 return -EINVAL;
1279 if (copy_to_user(optval, address, len))
1280 return -EFAULT;
1281 goto lenout;
1284 /* Dubious BSD thing... Probably nobody even uses it, but
1285 * the UNIX standard wants it for whatever reason... -DaveM
1287 case SO_ACCEPTCONN:
1288 v.val = sk->sk_state == TCP_LISTEN;
1289 break;
1291 case SO_PASSSEC:
1292 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1293 break;
1295 case SO_PEERSEC:
1296 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1298 case SO_MARK:
1299 v.val = sk->sk_mark;
1300 break;
1302 case SO_RXQ_OVFL:
1303 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1304 break;
1306 case SO_WIFI_STATUS:
1307 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1308 break;
1310 case SO_PEEK_OFF:
1311 if (!sock->ops->set_peek_off)
1312 return -EOPNOTSUPP;
1314 v.val = sk->sk_peek_off;
1315 break;
1316 case SO_NOFCS:
1317 v.val = sock_flag(sk, SOCK_NOFCS);
1318 break;
1320 case SO_BINDTODEVICE:
1321 return sock_getbindtodevice(sk, optval, optlen, len);
1323 case SO_GET_FILTER:
1324 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1325 if (len < 0)
1326 return len;
1328 goto lenout;
1330 case SO_LOCK_FILTER:
1331 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1332 break;
1334 case SO_BPF_EXTENSIONS:
1335 v.val = bpf_tell_extensions();
1336 break;
1338 case SO_SELECT_ERR_QUEUE:
1339 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1340 break;
1342 #ifdef CONFIG_NET_RX_BUSY_POLL
1343 case SO_BUSY_POLL:
1344 v.val = sk->sk_ll_usec;
1345 break;
1346 #endif
1348 case SO_MAX_PACING_RATE:
1349 v.val = sk->sk_max_pacing_rate;
1350 break;
1352 case SO_INCOMING_CPU:
1353 v.val = sk->sk_incoming_cpu;
1354 break;
1356 case SO_MEMINFO:
1358 u32 meminfo[SK_MEMINFO_VARS];
1360 if (get_user(len, optlen))
1361 return -EFAULT;
1363 sk_get_meminfo(sk, meminfo);
1365 len = min_t(unsigned int, len, sizeof(meminfo));
1366 if (copy_to_user(optval, &meminfo, len))
1367 return -EFAULT;
1369 goto lenout;
1372 #ifdef CONFIG_NET_RX_BUSY_POLL
1373 case SO_INCOMING_NAPI_ID:
1374 v.val = READ_ONCE(sk->sk_napi_id);
1376 /* aggregate non-NAPI IDs down to 0 */
1377 if (v.val < MIN_NAPI_ID)
1378 v.val = 0;
1380 break;
1381 #endif
1383 case SO_COOKIE:
1384 lv = sizeof(u64);
1385 if (len < lv)
1386 return -EINVAL;
1387 v.val64 = sock_gen_cookie(sk);
1388 break;
1390 case SO_ZEROCOPY:
1391 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1392 break;
1394 default:
1395 /* We implement the SO_SNDLOWAT etc to not be settable
1396 * (1003.1g 7).
1398 return -ENOPROTOOPT;
1401 if (len > lv)
1402 len = lv;
1403 if (copy_to_user(optval, &v, len))
1404 return -EFAULT;
1405 lenout:
1406 if (put_user(len, optlen))
1407 return -EFAULT;
1408 return 0;
1412 * Initialize an sk_lock.
1414 * (We also register the sk_lock with the lock validator.)
1416 static inline void sock_lock_init(struct sock *sk)
1418 if (sk->sk_kern_sock)
1419 sock_lock_init_class_and_name(
1421 af_family_kern_slock_key_strings[sk->sk_family],
1422 af_family_kern_slock_keys + sk->sk_family,
1423 af_family_kern_key_strings[sk->sk_family],
1424 af_family_kern_keys + sk->sk_family);
1425 else
1426 sock_lock_init_class_and_name(
1428 af_family_slock_key_strings[sk->sk_family],
1429 af_family_slock_keys + sk->sk_family,
1430 af_family_key_strings[sk->sk_family],
1431 af_family_keys + sk->sk_family);
1435 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1436 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1437 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1439 static void sock_copy(struct sock *nsk, const struct sock *osk)
1441 #ifdef CONFIG_SECURITY_NETWORK
1442 void *sptr = nsk->sk_security;
1443 #endif
1444 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1446 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1447 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1449 #ifdef CONFIG_SECURITY_NETWORK
1450 nsk->sk_security = sptr;
1451 security_sk_clone(osk, nsk);
1452 #endif
1455 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1456 int family)
1458 struct sock *sk;
1459 struct kmem_cache *slab;
1461 slab = prot->slab;
1462 if (slab != NULL) {
1463 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1464 if (!sk)
1465 return sk;
1466 if (priority & __GFP_ZERO)
1467 sk_prot_clear_nulls(sk, prot->obj_size);
1468 } else
1469 sk = kmalloc(prot->obj_size, priority);
1471 if (sk != NULL) {
1472 kmemcheck_annotate_bitfield(sk, flags);
1474 if (security_sk_alloc(sk, family, priority))
1475 goto out_free;
1477 if (!try_module_get(prot->owner))
1478 goto out_free_sec;
1479 sk_tx_queue_clear(sk);
1482 return sk;
1484 out_free_sec:
1485 security_sk_free(sk);
1486 out_free:
1487 if (slab != NULL)
1488 kmem_cache_free(slab, sk);
1489 else
1490 kfree(sk);
1491 return NULL;
1494 static void sk_prot_free(struct proto *prot, struct sock *sk)
1496 struct kmem_cache *slab;
1497 struct module *owner;
1499 owner = prot->owner;
1500 slab = prot->slab;
1502 cgroup_sk_free(&sk->sk_cgrp_data);
1503 mem_cgroup_sk_free(sk);
1504 security_sk_free(sk);
1505 if (slab != NULL)
1506 kmem_cache_free(slab, sk);
1507 else
1508 kfree(sk);
1509 module_put(owner);
1513 * sk_alloc - All socket objects are allocated here
1514 * @net: the applicable net namespace
1515 * @family: protocol family
1516 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1517 * @prot: struct proto associated with this new sock instance
1518 * @kern: is this to be a kernel socket?
1520 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1521 struct proto *prot, int kern)
1523 struct sock *sk;
1525 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1526 if (sk) {
1527 sk->sk_family = family;
1529 * See comment in struct sock definition to understand
1530 * why we need sk_prot_creator -acme
1532 sk->sk_prot = sk->sk_prot_creator = prot;
1533 sk->sk_kern_sock = kern;
1534 sock_lock_init(sk);
1535 sk->sk_net_refcnt = kern ? 0 : 1;
1536 if (likely(sk->sk_net_refcnt))
1537 get_net(net);
1538 sock_net_set(sk, net);
1539 refcount_set(&sk->sk_wmem_alloc, 1);
1541 mem_cgroup_sk_alloc(sk);
1542 cgroup_sk_alloc(&sk->sk_cgrp_data);
1543 sock_update_classid(&sk->sk_cgrp_data);
1544 sock_update_netprioidx(&sk->sk_cgrp_data);
1547 return sk;
1549 EXPORT_SYMBOL(sk_alloc);
1551 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1552 * grace period. This is the case for UDP sockets and TCP listeners.
1554 static void __sk_destruct(struct rcu_head *head)
1556 struct sock *sk = container_of(head, struct sock, sk_rcu);
1557 struct sk_filter *filter;
1559 if (sk->sk_destruct)
1560 sk->sk_destruct(sk);
1562 filter = rcu_dereference_check(sk->sk_filter,
1563 refcount_read(&sk->sk_wmem_alloc) == 0);
1564 if (filter) {
1565 sk_filter_uncharge(sk, filter);
1566 RCU_INIT_POINTER(sk->sk_filter, NULL);
1568 if (rcu_access_pointer(sk->sk_reuseport_cb))
1569 reuseport_detach_sock(sk);
1571 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1573 if (atomic_read(&sk->sk_omem_alloc))
1574 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1575 __func__, atomic_read(&sk->sk_omem_alloc));
1577 if (sk->sk_frag.page) {
1578 put_page(sk->sk_frag.page);
1579 sk->sk_frag.page = NULL;
1582 if (sk->sk_peer_cred)
1583 put_cred(sk->sk_peer_cred);
1584 put_pid(sk->sk_peer_pid);
1585 if (likely(sk->sk_net_refcnt))
1586 put_net(sock_net(sk));
1587 sk_prot_free(sk->sk_prot_creator, sk);
1590 void sk_destruct(struct sock *sk)
1592 if (sock_flag(sk, SOCK_RCU_FREE))
1593 call_rcu(&sk->sk_rcu, __sk_destruct);
1594 else
1595 __sk_destruct(&sk->sk_rcu);
1598 static void __sk_free(struct sock *sk)
1600 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1601 sock_diag_broadcast_destroy(sk);
1602 else
1603 sk_destruct(sk);
1606 void sk_free(struct sock *sk)
1609 * We subtract one from sk_wmem_alloc and can know if
1610 * some packets are still in some tx queue.
1611 * If not null, sock_wfree() will call __sk_free(sk) later
1613 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1614 __sk_free(sk);
1616 EXPORT_SYMBOL(sk_free);
1618 static void sk_init_common(struct sock *sk)
1620 skb_queue_head_init(&sk->sk_receive_queue);
1621 skb_queue_head_init(&sk->sk_write_queue);
1622 skb_queue_head_init(&sk->sk_error_queue);
1624 rwlock_init(&sk->sk_callback_lock);
1625 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1626 af_rlock_keys + sk->sk_family,
1627 af_family_rlock_key_strings[sk->sk_family]);
1628 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1629 af_wlock_keys + sk->sk_family,
1630 af_family_wlock_key_strings[sk->sk_family]);
1631 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1632 af_elock_keys + sk->sk_family,
1633 af_family_elock_key_strings[sk->sk_family]);
1634 lockdep_set_class_and_name(&sk->sk_callback_lock,
1635 af_callback_keys + sk->sk_family,
1636 af_family_clock_key_strings[sk->sk_family]);
1640 * sk_clone_lock - clone a socket, and lock its clone
1641 * @sk: the socket to clone
1642 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1644 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1646 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1648 struct sock *newsk;
1649 bool is_charged = true;
1651 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1652 if (newsk != NULL) {
1653 struct sk_filter *filter;
1655 sock_copy(newsk, sk);
1657 newsk->sk_prot_creator = sk->sk_prot;
1659 /* SANITY */
1660 if (likely(newsk->sk_net_refcnt))
1661 get_net(sock_net(newsk));
1662 sk_node_init(&newsk->sk_node);
1663 sock_lock_init(newsk);
1664 bh_lock_sock(newsk);
1665 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1666 newsk->sk_backlog.len = 0;
1668 atomic_set(&newsk->sk_rmem_alloc, 0);
1670 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1672 refcount_set(&newsk->sk_wmem_alloc, 1);
1673 atomic_set(&newsk->sk_omem_alloc, 0);
1674 sk_init_common(newsk);
1676 newsk->sk_dst_cache = NULL;
1677 newsk->sk_dst_pending_confirm = 0;
1678 newsk->sk_wmem_queued = 0;
1679 newsk->sk_forward_alloc = 0;
1681 /* sk->sk_memcg will be populated at accept() time */
1682 newsk->sk_memcg = NULL;
1684 atomic_set(&newsk->sk_drops, 0);
1685 newsk->sk_send_head = NULL;
1686 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1687 atomic_set(&newsk->sk_zckey, 0);
1689 sock_reset_flag(newsk, SOCK_DONE);
1690 cgroup_sk_alloc(&newsk->sk_cgrp_data);
1692 rcu_read_lock();
1693 filter = rcu_dereference(sk->sk_filter);
1694 if (filter != NULL)
1695 /* though it's an empty new sock, the charging may fail
1696 * if sysctl_optmem_max was changed between creation of
1697 * original socket and cloning
1699 is_charged = sk_filter_charge(newsk, filter);
1700 RCU_INIT_POINTER(newsk->sk_filter, filter);
1701 rcu_read_unlock();
1703 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1704 /* We need to make sure that we don't uncharge the new
1705 * socket if we couldn't charge it in the first place
1706 * as otherwise we uncharge the parent's filter.
1708 if (!is_charged)
1709 RCU_INIT_POINTER(newsk->sk_filter, NULL);
1710 sk_free_unlock_clone(newsk);
1711 newsk = NULL;
1712 goto out;
1714 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1716 newsk->sk_err = 0;
1717 newsk->sk_err_soft = 0;
1718 newsk->sk_priority = 0;
1719 newsk->sk_incoming_cpu = raw_smp_processor_id();
1720 atomic64_set(&newsk->sk_cookie, 0);
1723 * Before updating sk_refcnt, we must commit prior changes to memory
1724 * (Documentation/RCU/rculist_nulls.txt for details)
1726 smp_wmb();
1727 refcount_set(&newsk->sk_refcnt, 2);
1730 * Increment the counter in the same struct proto as the master
1731 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1732 * is the same as sk->sk_prot->socks, as this field was copied
1733 * with memcpy).
1735 * This _changes_ the previous behaviour, where
1736 * tcp_create_openreq_child always was incrementing the
1737 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1738 * to be taken into account in all callers. -acme
1740 sk_refcnt_debug_inc(newsk);
1741 sk_set_socket(newsk, NULL);
1742 newsk->sk_wq = NULL;
1744 if (newsk->sk_prot->sockets_allocated)
1745 sk_sockets_allocated_inc(newsk);
1747 if (sock_needs_netstamp(sk) &&
1748 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1749 net_enable_timestamp();
1751 out:
1752 return newsk;
1754 EXPORT_SYMBOL_GPL(sk_clone_lock);
1756 void sk_free_unlock_clone(struct sock *sk)
1758 /* It is still raw copy of parent, so invalidate
1759 * destructor and make plain sk_free() */
1760 sk->sk_destruct = NULL;
1761 bh_unlock_sock(sk);
1762 sk_free(sk);
1764 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1766 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1768 u32 max_segs = 1;
1770 sk_dst_set(sk, dst);
1771 sk->sk_route_caps = dst->dev->features;
1772 if (sk->sk_route_caps & NETIF_F_GSO)
1773 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1774 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1775 if (sk_can_gso(sk)) {
1776 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1777 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1778 } else {
1779 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1780 sk->sk_gso_max_size = dst->dev->gso_max_size;
1781 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1784 sk->sk_gso_max_segs = max_segs;
1786 EXPORT_SYMBOL_GPL(sk_setup_caps);
1789 * Simple resource managers for sockets.
1794 * Write buffer destructor automatically called from kfree_skb.
1796 void sock_wfree(struct sk_buff *skb)
1798 struct sock *sk = skb->sk;
1799 unsigned int len = skb->truesize;
1801 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1803 * Keep a reference on sk_wmem_alloc, this will be released
1804 * after sk_write_space() call
1806 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1807 sk->sk_write_space(sk);
1808 len = 1;
1811 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1812 * could not do because of in-flight packets
1814 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1815 __sk_free(sk);
1817 EXPORT_SYMBOL(sock_wfree);
1819 /* This variant of sock_wfree() is used by TCP,
1820 * since it sets SOCK_USE_WRITE_QUEUE.
1822 void __sock_wfree(struct sk_buff *skb)
1824 struct sock *sk = skb->sk;
1826 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1827 __sk_free(sk);
1830 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1832 skb_orphan(skb);
1833 skb->sk = sk;
1834 #ifdef CONFIG_INET
1835 if (unlikely(!sk_fullsock(sk))) {
1836 skb->destructor = sock_edemux;
1837 sock_hold(sk);
1838 return;
1840 #endif
1841 skb->destructor = sock_wfree;
1842 skb_set_hash_from_sk(skb, sk);
1844 * We used to take a refcount on sk, but following operation
1845 * is enough to guarantee sk_free() wont free this sock until
1846 * all in-flight packets are completed
1848 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1850 EXPORT_SYMBOL(skb_set_owner_w);
1852 /* This helper is used by netem, as it can hold packets in its
1853 * delay queue. We want to allow the owner socket to send more
1854 * packets, as if they were already TX completed by a typical driver.
1855 * But we also want to keep skb->sk set because some packet schedulers
1856 * rely on it (sch_fq for example).
1858 void skb_orphan_partial(struct sk_buff *skb)
1860 if (skb_is_tcp_pure_ack(skb))
1861 return;
1863 if (skb->destructor == sock_wfree
1864 #ifdef CONFIG_INET
1865 || skb->destructor == tcp_wfree
1866 #endif
1868 struct sock *sk = skb->sk;
1870 if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1871 WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
1872 skb->destructor = sock_efree;
1874 } else {
1875 skb_orphan(skb);
1878 EXPORT_SYMBOL(skb_orphan_partial);
1881 * Read buffer destructor automatically called from kfree_skb.
1883 void sock_rfree(struct sk_buff *skb)
1885 struct sock *sk = skb->sk;
1886 unsigned int len = skb->truesize;
1888 atomic_sub(len, &sk->sk_rmem_alloc);
1889 sk_mem_uncharge(sk, len);
1891 EXPORT_SYMBOL(sock_rfree);
1894 * Buffer destructor for skbs that are not used directly in read or write
1895 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1897 void sock_efree(struct sk_buff *skb)
1899 sock_put(skb->sk);
1901 EXPORT_SYMBOL(sock_efree);
1903 kuid_t sock_i_uid(struct sock *sk)
1905 kuid_t uid;
1907 read_lock_bh(&sk->sk_callback_lock);
1908 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1909 read_unlock_bh(&sk->sk_callback_lock);
1910 return uid;
1912 EXPORT_SYMBOL(sock_i_uid);
1914 unsigned long sock_i_ino(struct sock *sk)
1916 unsigned long ino;
1918 read_lock_bh(&sk->sk_callback_lock);
1919 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1920 read_unlock_bh(&sk->sk_callback_lock);
1921 return ino;
1923 EXPORT_SYMBOL(sock_i_ino);
1926 * Allocate a skb from the socket's send buffer.
1928 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1929 gfp_t priority)
1931 if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1932 struct sk_buff *skb = alloc_skb(size, priority);
1933 if (skb) {
1934 skb_set_owner_w(skb, sk);
1935 return skb;
1938 return NULL;
1940 EXPORT_SYMBOL(sock_wmalloc);
1942 static void sock_ofree(struct sk_buff *skb)
1944 struct sock *sk = skb->sk;
1946 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
1949 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1950 gfp_t priority)
1952 struct sk_buff *skb;
1954 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
1955 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
1956 sysctl_optmem_max)
1957 return NULL;
1959 skb = alloc_skb(size, priority);
1960 if (!skb)
1961 return NULL;
1963 atomic_add(skb->truesize, &sk->sk_omem_alloc);
1964 skb->sk = sk;
1965 skb->destructor = sock_ofree;
1966 return skb;
1970 * Allocate a memory block from the socket's option memory buffer.
1972 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1974 if ((unsigned int)size <= sysctl_optmem_max &&
1975 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1976 void *mem;
1977 /* First do the add, to avoid the race if kmalloc
1978 * might sleep.
1980 atomic_add(size, &sk->sk_omem_alloc);
1981 mem = kmalloc(size, priority);
1982 if (mem)
1983 return mem;
1984 atomic_sub(size, &sk->sk_omem_alloc);
1986 return NULL;
1988 EXPORT_SYMBOL(sock_kmalloc);
1990 /* Free an option memory block. Note, we actually want the inline
1991 * here as this allows gcc to detect the nullify and fold away the
1992 * condition entirely.
1994 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1995 const bool nullify)
1997 if (WARN_ON_ONCE(!mem))
1998 return;
1999 if (nullify)
2000 kzfree(mem);
2001 else
2002 kfree(mem);
2003 atomic_sub(size, &sk->sk_omem_alloc);
2006 void sock_kfree_s(struct sock *sk, void *mem, int size)
2008 __sock_kfree_s(sk, mem, size, false);
2010 EXPORT_SYMBOL(sock_kfree_s);
2012 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2014 __sock_kfree_s(sk, mem, size, true);
2016 EXPORT_SYMBOL(sock_kzfree_s);
2018 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2019 I think, these locks should be removed for datagram sockets.
2021 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2023 DEFINE_WAIT(wait);
2025 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2026 for (;;) {
2027 if (!timeo)
2028 break;
2029 if (signal_pending(current))
2030 break;
2031 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2032 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2033 if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2034 break;
2035 if (sk->sk_shutdown & SEND_SHUTDOWN)
2036 break;
2037 if (sk->sk_err)
2038 break;
2039 timeo = schedule_timeout(timeo);
2041 finish_wait(sk_sleep(sk), &wait);
2042 return timeo;
2047 * Generic send/receive buffer handlers
2050 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2051 unsigned long data_len, int noblock,
2052 int *errcode, int max_page_order)
2054 struct sk_buff *skb;
2055 long timeo;
2056 int err;
2058 timeo = sock_sndtimeo(sk, noblock);
2059 for (;;) {
2060 err = sock_error(sk);
2061 if (err != 0)
2062 goto failure;
2064 err = -EPIPE;
2065 if (sk->sk_shutdown & SEND_SHUTDOWN)
2066 goto failure;
2068 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2069 break;
2071 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2072 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2073 err = -EAGAIN;
2074 if (!timeo)
2075 goto failure;
2076 if (signal_pending(current))
2077 goto interrupted;
2078 timeo = sock_wait_for_wmem(sk, timeo);
2080 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2081 errcode, sk->sk_allocation);
2082 if (skb)
2083 skb_set_owner_w(skb, sk);
2084 return skb;
2086 interrupted:
2087 err = sock_intr_errno(timeo);
2088 failure:
2089 *errcode = err;
2090 return NULL;
2092 EXPORT_SYMBOL(sock_alloc_send_pskb);
2094 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2095 int noblock, int *errcode)
2097 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2099 EXPORT_SYMBOL(sock_alloc_send_skb);
2101 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2102 struct sockcm_cookie *sockc)
2104 u32 tsflags;
2106 switch (cmsg->cmsg_type) {
2107 case SO_MARK:
2108 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2109 return -EPERM;
2110 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2111 return -EINVAL;
2112 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2113 break;
2114 case SO_TIMESTAMPING:
2115 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2116 return -EINVAL;
2118 tsflags = *(u32 *)CMSG_DATA(cmsg);
2119 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2120 return -EINVAL;
2122 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2123 sockc->tsflags |= tsflags;
2124 break;
2125 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2126 case SCM_RIGHTS:
2127 case SCM_CREDENTIALS:
2128 break;
2129 default:
2130 return -EINVAL;
2132 return 0;
2134 EXPORT_SYMBOL(__sock_cmsg_send);
2136 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2137 struct sockcm_cookie *sockc)
2139 struct cmsghdr *cmsg;
2140 int ret;
2142 for_each_cmsghdr(cmsg, msg) {
2143 if (!CMSG_OK(msg, cmsg))
2144 return -EINVAL;
2145 if (cmsg->cmsg_level != SOL_SOCKET)
2146 continue;
2147 ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2148 if (ret)
2149 return ret;
2151 return 0;
2153 EXPORT_SYMBOL(sock_cmsg_send);
2155 static void sk_enter_memory_pressure(struct sock *sk)
2157 if (!sk->sk_prot->enter_memory_pressure)
2158 return;
2160 sk->sk_prot->enter_memory_pressure(sk);
2163 static void sk_leave_memory_pressure(struct sock *sk)
2165 if (sk->sk_prot->leave_memory_pressure) {
2166 sk->sk_prot->leave_memory_pressure(sk);
2167 } else {
2168 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2170 if (memory_pressure && *memory_pressure)
2171 *memory_pressure = 0;
2175 /* On 32bit arches, an skb frag is limited to 2^15 */
2176 #define SKB_FRAG_PAGE_ORDER get_order(32768)
2179 * skb_page_frag_refill - check that a page_frag contains enough room
2180 * @sz: minimum size of the fragment we want to get
2181 * @pfrag: pointer to page_frag
2182 * @gfp: priority for memory allocation
2184 * Note: While this allocator tries to use high order pages, there is
2185 * no guarantee that allocations succeed. Therefore, @sz MUST be
2186 * less or equal than PAGE_SIZE.
2188 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2190 if (pfrag->page) {
2191 if (page_ref_count(pfrag->page) == 1) {
2192 pfrag->offset = 0;
2193 return true;
2195 if (pfrag->offset + sz <= pfrag->size)
2196 return true;
2197 put_page(pfrag->page);
2200 pfrag->offset = 0;
2201 if (SKB_FRAG_PAGE_ORDER) {
2202 /* Avoid direct reclaim but allow kswapd to wake */
2203 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2204 __GFP_COMP | __GFP_NOWARN |
2205 __GFP_NORETRY,
2206 SKB_FRAG_PAGE_ORDER);
2207 if (likely(pfrag->page)) {
2208 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2209 return true;
2212 pfrag->page = alloc_page(gfp);
2213 if (likely(pfrag->page)) {
2214 pfrag->size = PAGE_SIZE;
2215 return true;
2217 return false;
2219 EXPORT_SYMBOL(skb_page_frag_refill);
2221 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2223 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2224 return true;
2226 sk_enter_memory_pressure(sk);
2227 sk_stream_moderate_sndbuf(sk);
2228 return false;
2230 EXPORT_SYMBOL(sk_page_frag_refill);
2232 static void __lock_sock(struct sock *sk)
2233 __releases(&sk->sk_lock.slock)
2234 __acquires(&sk->sk_lock.slock)
2236 DEFINE_WAIT(wait);
2238 for (;;) {
2239 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2240 TASK_UNINTERRUPTIBLE);
2241 spin_unlock_bh(&sk->sk_lock.slock);
2242 schedule();
2243 spin_lock_bh(&sk->sk_lock.slock);
2244 if (!sock_owned_by_user(sk))
2245 break;
2247 finish_wait(&sk->sk_lock.wq, &wait);
2250 static void __release_sock(struct sock *sk)
2251 __releases(&sk->sk_lock.slock)
2252 __acquires(&sk->sk_lock.slock)
2254 struct sk_buff *skb, *next;
2256 while ((skb = sk->sk_backlog.head) != NULL) {
2257 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2259 spin_unlock_bh(&sk->sk_lock.slock);
2261 do {
2262 next = skb->next;
2263 prefetch(next);
2264 WARN_ON_ONCE(skb_dst_is_noref(skb));
2265 skb->next = NULL;
2266 sk_backlog_rcv(sk, skb);
2268 cond_resched();
2270 skb = next;
2271 } while (skb != NULL);
2273 spin_lock_bh(&sk->sk_lock.slock);
2277 * Doing the zeroing here guarantee we can not loop forever
2278 * while a wild producer attempts to flood us.
2280 sk->sk_backlog.len = 0;
2283 void __sk_flush_backlog(struct sock *sk)
2285 spin_lock_bh(&sk->sk_lock.slock);
2286 __release_sock(sk);
2287 spin_unlock_bh(&sk->sk_lock.slock);
2291 * sk_wait_data - wait for data to arrive at sk_receive_queue
2292 * @sk: sock to wait on
2293 * @timeo: for how long
2294 * @skb: last skb seen on sk_receive_queue
2296 * Now socket state including sk->sk_err is changed only under lock,
2297 * hence we may omit checks after joining wait queue.
2298 * We check receive queue before schedule() only as optimization;
2299 * it is very likely that release_sock() added new data.
2301 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2303 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2304 int rc;
2306 add_wait_queue(sk_sleep(sk), &wait);
2307 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2308 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2309 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2310 remove_wait_queue(sk_sleep(sk), &wait);
2311 return rc;
2313 EXPORT_SYMBOL(sk_wait_data);
2316 * __sk_mem_raise_allocated - increase memory_allocated
2317 * @sk: socket
2318 * @size: memory size to allocate
2319 * @amt: pages to allocate
2320 * @kind: allocation type
2322 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2324 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2326 struct proto *prot = sk->sk_prot;
2327 long allocated = sk_memory_allocated_add(sk, amt);
2329 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2330 !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2331 goto suppress_allocation;
2333 /* Under limit. */
2334 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2335 sk_leave_memory_pressure(sk);
2336 return 1;
2339 /* Under pressure. */
2340 if (allocated > sk_prot_mem_limits(sk, 1))
2341 sk_enter_memory_pressure(sk);
2343 /* Over hard limit. */
2344 if (allocated > sk_prot_mem_limits(sk, 2))
2345 goto suppress_allocation;
2347 /* guarantee minimum buffer size under pressure */
2348 if (kind == SK_MEM_RECV) {
2349 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2350 return 1;
2352 } else { /* SK_MEM_SEND */
2353 if (sk->sk_type == SOCK_STREAM) {
2354 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2355 return 1;
2356 } else if (refcount_read(&sk->sk_wmem_alloc) <
2357 prot->sysctl_wmem[0])
2358 return 1;
2361 if (sk_has_memory_pressure(sk)) {
2362 int alloc;
2364 if (!sk_under_memory_pressure(sk))
2365 return 1;
2366 alloc = sk_sockets_allocated_read_positive(sk);
2367 if (sk_prot_mem_limits(sk, 2) > alloc *
2368 sk_mem_pages(sk->sk_wmem_queued +
2369 atomic_read(&sk->sk_rmem_alloc) +
2370 sk->sk_forward_alloc))
2371 return 1;
2374 suppress_allocation:
2376 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2377 sk_stream_moderate_sndbuf(sk);
2379 /* Fail only if socket is _under_ its sndbuf.
2380 * In this case we cannot block, so that we have to fail.
2382 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2383 return 1;
2386 trace_sock_exceed_buf_limit(sk, prot, allocated);
2388 sk_memory_allocated_sub(sk, amt);
2390 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2391 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2393 return 0;
2395 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2398 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2399 * @sk: socket
2400 * @size: memory size to allocate
2401 * @kind: allocation type
2403 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2404 * rmem allocation. This function assumes that protocols which have
2405 * memory_pressure use sk_wmem_queued as write buffer accounting.
2407 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2409 int ret, amt = sk_mem_pages(size);
2411 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2412 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2413 if (!ret)
2414 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2415 return ret;
2417 EXPORT_SYMBOL(__sk_mem_schedule);
2420 * __sk_mem_reduce_allocated - reclaim memory_allocated
2421 * @sk: socket
2422 * @amount: number of quanta
2424 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2426 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2428 sk_memory_allocated_sub(sk, amount);
2430 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2431 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2433 if (sk_under_memory_pressure(sk) &&
2434 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2435 sk_leave_memory_pressure(sk);
2437 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2440 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2441 * @sk: socket
2442 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2444 void __sk_mem_reclaim(struct sock *sk, int amount)
2446 amount >>= SK_MEM_QUANTUM_SHIFT;
2447 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2448 __sk_mem_reduce_allocated(sk, amount);
2450 EXPORT_SYMBOL(__sk_mem_reclaim);
2452 int sk_set_peek_off(struct sock *sk, int val)
2454 sk->sk_peek_off = val;
2455 return 0;
2457 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2460 * Set of default routines for initialising struct proto_ops when
2461 * the protocol does not support a particular function. In certain
2462 * cases where it makes no sense for a protocol to have a "do nothing"
2463 * function, some default processing is provided.
2466 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2468 return -EOPNOTSUPP;
2470 EXPORT_SYMBOL(sock_no_bind);
2472 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2473 int len, int flags)
2475 return -EOPNOTSUPP;
2477 EXPORT_SYMBOL(sock_no_connect);
2479 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2481 return -EOPNOTSUPP;
2483 EXPORT_SYMBOL(sock_no_socketpair);
2485 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2486 bool kern)
2488 return -EOPNOTSUPP;
2490 EXPORT_SYMBOL(sock_no_accept);
2492 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2493 int *len, int peer)
2495 return -EOPNOTSUPP;
2497 EXPORT_SYMBOL(sock_no_getname);
2499 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2501 return 0;
2503 EXPORT_SYMBOL(sock_no_poll);
2505 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2507 return -EOPNOTSUPP;
2509 EXPORT_SYMBOL(sock_no_ioctl);
2511 int sock_no_listen(struct socket *sock, int backlog)
2513 return -EOPNOTSUPP;
2515 EXPORT_SYMBOL(sock_no_listen);
2517 int sock_no_shutdown(struct socket *sock, int how)
2519 return -EOPNOTSUPP;
2521 EXPORT_SYMBOL(sock_no_shutdown);
2523 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2524 char __user *optval, unsigned int optlen)
2526 return -EOPNOTSUPP;
2528 EXPORT_SYMBOL(sock_no_setsockopt);
2530 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2531 char __user *optval, int __user *optlen)
2533 return -EOPNOTSUPP;
2535 EXPORT_SYMBOL(sock_no_getsockopt);
2537 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2539 return -EOPNOTSUPP;
2541 EXPORT_SYMBOL(sock_no_sendmsg);
2543 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2545 return -EOPNOTSUPP;
2547 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2549 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2550 int flags)
2552 return -EOPNOTSUPP;
2554 EXPORT_SYMBOL(sock_no_recvmsg);
2556 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2558 /* Mirror missing mmap method error code */
2559 return -ENODEV;
2561 EXPORT_SYMBOL(sock_no_mmap);
2563 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2565 ssize_t res;
2566 struct msghdr msg = {.msg_flags = flags};
2567 struct kvec iov;
2568 char *kaddr = kmap(page);
2569 iov.iov_base = kaddr + offset;
2570 iov.iov_len = size;
2571 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2572 kunmap(page);
2573 return res;
2575 EXPORT_SYMBOL(sock_no_sendpage);
2577 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2578 int offset, size_t size, int flags)
2580 ssize_t res;
2581 struct msghdr msg = {.msg_flags = flags};
2582 struct kvec iov;
2583 char *kaddr = kmap(page);
2585 iov.iov_base = kaddr + offset;
2586 iov.iov_len = size;
2587 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2588 kunmap(page);
2589 return res;
2591 EXPORT_SYMBOL(sock_no_sendpage_locked);
2594 * Default Socket Callbacks
2597 static void sock_def_wakeup(struct sock *sk)
2599 struct socket_wq *wq;
2601 rcu_read_lock();
2602 wq = rcu_dereference(sk->sk_wq);
2603 if (skwq_has_sleeper(wq))
2604 wake_up_interruptible_all(&wq->wait);
2605 rcu_read_unlock();
2608 static void sock_def_error_report(struct sock *sk)
2610 struct socket_wq *wq;
2612 rcu_read_lock();
2613 wq = rcu_dereference(sk->sk_wq);
2614 if (skwq_has_sleeper(wq))
2615 wake_up_interruptible_poll(&wq->wait, POLLERR);
2616 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2617 rcu_read_unlock();
2620 static void sock_def_readable(struct sock *sk)
2622 struct socket_wq *wq;
2624 rcu_read_lock();
2625 wq = rcu_dereference(sk->sk_wq);
2626 if (skwq_has_sleeper(wq))
2627 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2628 POLLRDNORM | POLLRDBAND);
2629 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2630 rcu_read_unlock();
2633 static void sock_def_write_space(struct sock *sk)
2635 struct socket_wq *wq;
2637 rcu_read_lock();
2639 /* Do not wake up a writer until he can make "significant"
2640 * progress. --DaveM
2642 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2643 wq = rcu_dereference(sk->sk_wq);
2644 if (skwq_has_sleeper(wq))
2645 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2646 POLLWRNORM | POLLWRBAND);
2648 /* Should agree with poll, otherwise some programs break */
2649 if (sock_writeable(sk))
2650 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2653 rcu_read_unlock();
2656 static void sock_def_destruct(struct sock *sk)
2660 void sk_send_sigurg(struct sock *sk)
2662 if (sk->sk_socket && sk->sk_socket->file)
2663 if (send_sigurg(&sk->sk_socket->file->f_owner))
2664 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2666 EXPORT_SYMBOL(sk_send_sigurg);
2668 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2669 unsigned long expires)
2671 if (!mod_timer(timer, expires))
2672 sock_hold(sk);
2674 EXPORT_SYMBOL(sk_reset_timer);
2676 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2678 if (del_timer(timer))
2679 __sock_put(sk);
2681 EXPORT_SYMBOL(sk_stop_timer);
2683 void sock_init_data(struct socket *sock, struct sock *sk)
2685 sk_init_common(sk);
2686 sk->sk_send_head = NULL;
2688 init_timer(&sk->sk_timer);
2690 sk->sk_allocation = GFP_KERNEL;
2691 sk->sk_rcvbuf = sysctl_rmem_default;
2692 sk->sk_sndbuf = sysctl_wmem_default;
2693 sk->sk_state = TCP_CLOSE;
2694 sk_set_socket(sk, sock);
2696 sock_set_flag(sk, SOCK_ZAPPED);
2698 if (sock) {
2699 sk->sk_type = sock->type;
2700 sk->sk_wq = sock->wq;
2701 sock->sk = sk;
2702 sk->sk_uid = SOCK_INODE(sock)->i_uid;
2703 } else {
2704 sk->sk_wq = NULL;
2705 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0);
2708 rwlock_init(&sk->sk_callback_lock);
2709 if (sk->sk_kern_sock)
2710 lockdep_set_class_and_name(
2711 &sk->sk_callback_lock,
2712 af_kern_callback_keys + sk->sk_family,
2713 af_family_kern_clock_key_strings[sk->sk_family]);
2714 else
2715 lockdep_set_class_and_name(
2716 &sk->sk_callback_lock,
2717 af_callback_keys + sk->sk_family,
2718 af_family_clock_key_strings[sk->sk_family]);
2720 sk->sk_state_change = sock_def_wakeup;
2721 sk->sk_data_ready = sock_def_readable;
2722 sk->sk_write_space = sock_def_write_space;
2723 sk->sk_error_report = sock_def_error_report;
2724 sk->sk_destruct = sock_def_destruct;
2726 sk->sk_frag.page = NULL;
2727 sk->sk_frag.offset = 0;
2728 sk->sk_peek_off = -1;
2730 sk->sk_peer_pid = NULL;
2731 sk->sk_peer_cred = NULL;
2732 sk->sk_write_pending = 0;
2733 sk->sk_rcvlowat = 1;
2734 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2735 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2737 sk->sk_stamp = SK_DEFAULT_STAMP;
2738 atomic_set(&sk->sk_zckey, 0);
2740 #ifdef CONFIG_NET_RX_BUSY_POLL
2741 sk->sk_napi_id = 0;
2742 sk->sk_ll_usec = sysctl_net_busy_read;
2743 #endif
2745 sk->sk_max_pacing_rate = ~0U;
2746 sk->sk_pacing_rate = ~0U;
2747 sk->sk_incoming_cpu = -1;
2749 * Before updating sk_refcnt, we must commit prior changes to memory
2750 * (Documentation/RCU/rculist_nulls.txt for details)
2752 smp_wmb();
2753 refcount_set(&sk->sk_refcnt, 1);
2754 atomic_set(&sk->sk_drops, 0);
2756 EXPORT_SYMBOL(sock_init_data);
2758 void lock_sock_nested(struct sock *sk, int subclass)
2760 might_sleep();
2761 spin_lock_bh(&sk->sk_lock.slock);
2762 if (sk->sk_lock.owned)
2763 __lock_sock(sk);
2764 sk->sk_lock.owned = 1;
2765 spin_unlock(&sk->sk_lock.slock);
2767 * The sk_lock has mutex_lock() semantics here:
2769 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2770 local_bh_enable();
2772 EXPORT_SYMBOL(lock_sock_nested);
2774 void release_sock(struct sock *sk)
2776 spin_lock_bh(&sk->sk_lock.slock);
2777 if (sk->sk_backlog.tail)
2778 __release_sock(sk);
2780 /* Warning : release_cb() might need to release sk ownership,
2781 * ie call sock_release_ownership(sk) before us.
2783 if (sk->sk_prot->release_cb)
2784 sk->sk_prot->release_cb(sk);
2786 sock_release_ownership(sk);
2787 if (waitqueue_active(&sk->sk_lock.wq))
2788 wake_up(&sk->sk_lock.wq);
2789 spin_unlock_bh(&sk->sk_lock.slock);
2791 EXPORT_SYMBOL(release_sock);
2794 * lock_sock_fast - fast version of lock_sock
2795 * @sk: socket
2797 * This version should be used for very small section, where process wont block
2798 * return false if fast path is taken:
2800 * sk_lock.slock locked, owned = 0, BH disabled
2802 * return true if slow path is taken:
2804 * sk_lock.slock unlocked, owned = 1, BH enabled
2806 bool lock_sock_fast(struct sock *sk)
2808 might_sleep();
2809 spin_lock_bh(&sk->sk_lock.slock);
2811 if (!sk->sk_lock.owned)
2813 * Note : We must disable BH
2815 return false;
2817 __lock_sock(sk);
2818 sk->sk_lock.owned = 1;
2819 spin_unlock(&sk->sk_lock.slock);
2821 * The sk_lock has mutex_lock() semantics here:
2823 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2824 local_bh_enable();
2825 return true;
2827 EXPORT_SYMBOL(lock_sock_fast);
2829 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2831 struct timeval tv;
2832 if (!sock_flag(sk, SOCK_TIMESTAMP))
2833 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2834 tv = ktime_to_timeval(sk->sk_stamp);
2835 if (tv.tv_sec == -1)
2836 return -ENOENT;
2837 if (tv.tv_sec == 0) {
2838 sk->sk_stamp = ktime_get_real();
2839 tv = ktime_to_timeval(sk->sk_stamp);
2841 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2843 EXPORT_SYMBOL(sock_get_timestamp);
2845 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2847 struct timespec ts;
2848 if (!sock_flag(sk, SOCK_TIMESTAMP))
2849 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2850 ts = ktime_to_timespec(sk->sk_stamp);
2851 if (ts.tv_sec == -1)
2852 return -ENOENT;
2853 if (ts.tv_sec == 0) {
2854 sk->sk_stamp = ktime_get_real();
2855 ts = ktime_to_timespec(sk->sk_stamp);
2857 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2859 EXPORT_SYMBOL(sock_get_timestampns);
2861 void sock_enable_timestamp(struct sock *sk, int flag)
2863 if (!sock_flag(sk, flag)) {
2864 unsigned long previous_flags = sk->sk_flags;
2866 sock_set_flag(sk, flag);
2868 * we just set one of the two flags which require net
2869 * time stamping, but time stamping might have been on
2870 * already because of the other one
2872 if (sock_needs_netstamp(sk) &&
2873 !(previous_flags & SK_FLAGS_TIMESTAMP))
2874 net_enable_timestamp();
2878 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2879 int level, int type)
2881 struct sock_exterr_skb *serr;
2882 struct sk_buff *skb;
2883 int copied, err;
2885 err = -EAGAIN;
2886 skb = sock_dequeue_err_skb(sk);
2887 if (skb == NULL)
2888 goto out;
2890 copied = skb->len;
2891 if (copied > len) {
2892 msg->msg_flags |= MSG_TRUNC;
2893 copied = len;
2895 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2896 if (err)
2897 goto out_free_skb;
2899 sock_recv_timestamp(msg, sk, skb);
2901 serr = SKB_EXT_ERR(skb);
2902 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2904 msg->msg_flags |= MSG_ERRQUEUE;
2905 err = copied;
2907 out_free_skb:
2908 kfree_skb(skb);
2909 out:
2910 return err;
2912 EXPORT_SYMBOL(sock_recv_errqueue);
2915 * Get a socket option on an socket.
2917 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2918 * asynchronous errors should be reported by getsockopt. We assume
2919 * this means if you specify SO_ERROR (otherwise whats the point of it).
2921 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2922 char __user *optval, int __user *optlen)
2924 struct sock *sk = sock->sk;
2926 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2928 EXPORT_SYMBOL(sock_common_getsockopt);
2930 #ifdef CONFIG_COMPAT
2931 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2932 char __user *optval, int __user *optlen)
2934 struct sock *sk = sock->sk;
2936 if (sk->sk_prot->compat_getsockopt != NULL)
2937 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2938 optval, optlen);
2939 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2941 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2942 #endif
2944 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2945 int flags)
2947 struct sock *sk = sock->sk;
2948 int addr_len = 0;
2949 int err;
2951 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2952 flags & ~MSG_DONTWAIT, &addr_len);
2953 if (err >= 0)
2954 msg->msg_namelen = addr_len;
2955 return err;
2957 EXPORT_SYMBOL(sock_common_recvmsg);
2960 * Set socket options on an inet socket.
2962 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2963 char __user *optval, unsigned int optlen)
2965 struct sock *sk = sock->sk;
2967 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2969 EXPORT_SYMBOL(sock_common_setsockopt);
2971 #ifdef CONFIG_COMPAT
2972 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2973 char __user *optval, unsigned int optlen)
2975 struct sock *sk = sock->sk;
2977 if (sk->sk_prot->compat_setsockopt != NULL)
2978 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2979 optval, optlen);
2980 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2982 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2983 #endif
2985 void sk_common_release(struct sock *sk)
2987 if (sk->sk_prot->destroy)
2988 sk->sk_prot->destroy(sk);
2991 * Observation: when sock_common_release is called, processes have
2992 * no access to socket. But net still has.
2993 * Step one, detach it from networking:
2995 * A. Remove from hash tables.
2998 sk->sk_prot->unhash(sk);
3001 * In this point socket cannot receive new packets, but it is possible
3002 * that some packets are in flight because some CPU runs receiver and
3003 * did hash table lookup before we unhashed socket. They will achieve
3004 * receive queue and will be purged by socket destructor.
3006 * Also we still have packets pending on receive queue and probably,
3007 * our own packets waiting in device queues. sock_destroy will drain
3008 * receive queue, but transmitted packets will delay socket destruction
3009 * until the last reference will be released.
3012 sock_orphan(sk);
3014 xfrm_sk_free_policy(sk);
3016 sk_refcnt_debug_release(sk);
3018 sock_put(sk);
3020 EXPORT_SYMBOL(sk_common_release);
3022 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3024 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3026 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3027 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3028 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3029 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3030 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3031 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3032 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3033 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3034 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3037 #ifdef CONFIG_PROC_FS
3038 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
3039 struct prot_inuse {
3040 int val[PROTO_INUSE_NR];
3043 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3045 #ifdef CONFIG_NET_NS
3046 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3048 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
3050 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3052 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3054 int cpu, idx = prot->inuse_idx;
3055 int res = 0;
3057 for_each_possible_cpu(cpu)
3058 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
3060 return res >= 0 ? res : 0;
3062 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3064 static int __net_init sock_inuse_init_net(struct net *net)
3066 net->core.inuse = alloc_percpu(struct prot_inuse);
3067 return net->core.inuse ? 0 : -ENOMEM;
3070 static void __net_exit sock_inuse_exit_net(struct net *net)
3072 free_percpu(net->core.inuse);
3075 static struct pernet_operations net_inuse_ops = {
3076 .init = sock_inuse_init_net,
3077 .exit = sock_inuse_exit_net,
3080 static __init int net_inuse_init(void)
3082 if (register_pernet_subsys(&net_inuse_ops))
3083 panic("Cannot initialize net inuse counters");
3085 return 0;
3088 core_initcall(net_inuse_init);
3089 #else
3090 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
3092 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3094 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
3096 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3098 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3100 int cpu, idx = prot->inuse_idx;
3101 int res = 0;
3103 for_each_possible_cpu(cpu)
3104 res += per_cpu(prot_inuse, cpu).val[idx];
3106 return res >= 0 ? res : 0;
3108 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3109 #endif
3111 static void assign_proto_idx(struct proto *prot)
3113 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3115 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3116 pr_err("PROTO_INUSE_NR exhausted\n");
3117 return;
3120 set_bit(prot->inuse_idx, proto_inuse_idx);
3123 static void release_proto_idx(struct proto *prot)
3125 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3126 clear_bit(prot->inuse_idx, proto_inuse_idx);
3128 #else
3129 static inline void assign_proto_idx(struct proto *prot)
3133 static inline void release_proto_idx(struct proto *prot)
3136 #endif
3138 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3140 if (!rsk_prot)
3141 return;
3142 kfree(rsk_prot->slab_name);
3143 rsk_prot->slab_name = NULL;
3144 kmem_cache_destroy(rsk_prot->slab);
3145 rsk_prot->slab = NULL;
3148 static int req_prot_init(const struct proto *prot)
3150 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3152 if (!rsk_prot)
3153 return 0;
3155 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3156 prot->name);
3157 if (!rsk_prot->slab_name)
3158 return -ENOMEM;
3160 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3161 rsk_prot->obj_size, 0,
3162 prot->slab_flags, NULL);
3164 if (!rsk_prot->slab) {
3165 pr_crit("%s: Can't create request sock SLAB cache!\n",
3166 prot->name);
3167 return -ENOMEM;
3169 return 0;
3172 int proto_register(struct proto *prot, int alloc_slab)
3174 if (alloc_slab) {
3175 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
3176 SLAB_HWCACHE_ALIGN | prot->slab_flags,
3177 NULL);
3179 if (prot->slab == NULL) {
3180 pr_crit("%s: Can't create sock SLAB cache!\n",
3181 prot->name);
3182 goto out;
3185 if (req_prot_init(prot))
3186 goto out_free_request_sock_slab;
3188 if (prot->twsk_prot != NULL) {
3189 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3191 if (prot->twsk_prot->twsk_slab_name == NULL)
3192 goto out_free_request_sock_slab;
3194 prot->twsk_prot->twsk_slab =
3195 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3196 prot->twsk_prot->twsk_obj_size,
3198 prot->slab_flags,
3199 NULL);
3200 if (prot->twsk_prot->twsk_slab == NULL)
3201 goto out_free_timewait_sock_slab_name;
3205 mutex_lock(&proto_list_mutex);
3206 list_add(&prot->node, &proto_list);
3207 assign_proto_idx(prot);
3208 mutex_unlock(&proto_list_mutex);
3209 return 0;
3211 out_free_timewait_sock_slab_name:
3212 kfree(prot->twsk_prot->twsk_slab_name);
3213 out_free_request_sock_slab:
3214 req_prot_cleanup(prot->rsk_prot);
3216 kmem_cache_destroy(prot->slab);
3217 prot->slab = NULL;
3218 out:
3219 return -ENOBUFS;
3221 EXPORT_SYMBOL(proto_register);
3223 void proto_unregister(struct proto *prot)
3225 mutex_lock(&proto_list_mutex);
3226 release_proto_idx(prot);
3227 list_del(&prot->node);
3228 mutex_unlock(&proto_list_mutex);
3230 kmem_cache_destroy(prot->slab);
3231 prot->slab = NULL;
3233 req_prot_cleanup(prot->rsk_prot);
3235 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3236 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3237 kfree(prot->twsk_prot->twsk_slab_name);
3238 prot->twsk_prot->twsk_slab = NULL;
3241 EXPORT_SYMBOL(proto_unregister);
3243 #ifdef CONFIG_PROC_FS
3244 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3245 __acquires(proto_list_mutex)
3247 mutex_lock(&proto_list_mutex);
3248 return seq_list_start_head(&proto_list, *pos);
3251 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3253 return seq_list_next(v, &proto_list, pos);
3256 static void proto_seq_stop(struct seq_file *seq, void *v)
3257 __releases(proto_list_mutex)
3259 mutex_unlock(&proto_list_mutex);
3262 static char proto_method_implemented(const void *method)
3264 return method == NULL ? 'n' : 'y';
3266 static long sock_prot_memory_allocated(struct proto *proto)
3268 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3271 static char *sock_prot_memory_pressure(struct proto *proto)
3273 return proto->memory_pressure != NULL ?
3274 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3277 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3280 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
3281 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3282 proto->name,
3283 proto->obj_size,
3284 sock_prot_inuse_get(seq_file_net(seq), proto),
3285 sock_prot_memory_allocated(proto),
3286 sock_prot_memory_pressure(proto),
3287 proto->max_header,
3288 proto->slab == NULL ? "no" : "yes",
3289 module_name(proto->owner),
3290 proto_method_implemented(proto->close),
3291 proto_method_implemented(proto->connect),
3292 proto_method_implemented(proto->disconnect),
3293 proto_method_implemented(proto->accept),
3294 proto_method_implemented(proto->ioctl),
3295 proto_method_implemented(proto->init),
3296 proto_method_implemented(proto->destroy),
3297 proto_method_implemented(proto->shutdown),
3298 proto_method_implemented(proto->setsockopt),
3299 proto_method_implemented(proto->getsockopt),
3300 proto_method_implemented(proto->sendmsg),
3301 proto_method_implemented(proto->recvmsg),
3302 proto_method_implemented(proto->sendpage),
3303 proto_method_implemented(proto->bind),
3304 proto_method_implemented(proto->backlog_rcv),
3305 proto_method_implemented(proto->hash),
3306 proto_method_implemented(proto->unhash),
3307 proto_method_implemented(proto->get_port),
3308 proto_method_implemented(proto->enter_memory_pressure));
3311 static int proto_seq_show(struct seq_file *seq, void *v)
3313 if (v == &proto_list)
3314 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3315 "protocol",
3316 "size",
3317 "sockets",
3318 "memory",
3319 "press",
3320 "maxhdr",
3321 "slab",
3322 "module",
3323 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3324 else
3325 proto_seq_printf(seq, list_entry(v, struct proto, node));
3326 return 0;
3329 static const struct seq_operations proto_seq_ops = {
3330 .start = proto_seq_start,
3331 .next = proto_seq_next,
3332 .stop = proto_seq_stop,
3333 .show = proto_seq_show,
3336 static int proto_seq_open(struct inode *inode, struct file *file)
3338 return seq_open_net(inode, file, &proto_seq_ops,
3339 sizeof(struct seq_net_private));
3342 static const struct file_operations proto_seq_fops = {
3343 .owner = THIS_MODULE,
3344 .open = proto_seq_open,
3345 .read = seq_read,
3346 .llseek = seq_lseek,
3347 .release = seq_release_net,
3350 static __net_init int proto_init_net(struct net *net)
3352 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3353 return -ENOMEM;
3355 return 0;
3358 static __net_exit void proto_exit_net(struct net *net)
3360 remove_proc_entry("protocols", net->proc_net);
3364 static __net_initdata struct pernet_operations proto_net_ops = {
3365 .init = proto_init_net,
3366 .exit = proto_exit_net,
3369 static int __init proto_init(void)
3371 return register_pernet_subsys(&proto_net_ops);
3374 subsys_initcall(proto_init);
3376 #endif /* PROC_FS */
3378 #ifdef CONFIG_NET_RX_BUSY_POLL
3379 bool sk_busy_loop_end(void *p, unsigned long start_time)
3381 struct sock *sk = p;
3383 return !skb_queue_empty(&sk->sk_receive_queue) ||
3384 sk_busy_loop_timeout(sk, start_time);
3386 EXPORT_SYMBOL(sk_busy_loop_end);
3387 #endif /* CONFIG_NET_RX_BUSY_POLL */