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Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
[deliverable/linux.git] / net / core / sock.c
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.
5 *
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
8 *
9 *
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>
14 *
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
82 *
83 * To Fix:
84 *
85 *
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.
90 */
91
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93
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/timer.h>
106 #include <linux/string.h>
107 #include <linux/sockios.h>
108 #include <linux/net.h>
109 #include <linux/mm.h>
110 #include <linux/slab.h>
111 #include <linux/interrupt.h>
112 #include <linux/poll.h>
113 #include <linux/tcp.h>
114 #include <linux/init.h>
115 #include <linux/highmem.h>
116 #include <linux/user_namespace.h>
117 #include <linux/static_key.h>
118 #include <linux/memcontrol.h>
119 #include <linux/prefetch.h>
120
121 #include <asm/uaccess.h>
122
123 #include <linux/netdevice.h>
124 #include <net/protocol.h>
125 #include <linux/skbuff.h>
126 #include <net/net_namespace.h>
127 #include <net/request_sock.h>
128 #include <net/sock.h>
129 #include <linux/net_tstamp.h>
130 #include <net/xfrm.h>
131 #include <linux/ipsec.h>
132 #include <net/cls_cgroup.h>
133 #include <net/netprio_cgroup.h>
134 #include <linux/sock_diag.h>
135
136 #include <linux/filter.h>
137
138 #include <trace/events/sock.h>
139
140 #ifdef CONFIG_INET
141 #include <net/tcp.h>
142 #endif
143
144 #include <net/busy_poll.h>
145
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148
149 /**
150 * sk_ns_capable - General socket capability test
151 * @sk: Socket to use a capability on or through
152 * @user_ns: The user namespace of the capability to use
153 * @cap: The capability to use
154 *
155 * Test to see if the opener of the socket had when the socket was
156 * created and the current process has the capability @cap in the user
157 * namespace @user_ns.
158 */
159 bool sk_ns_capable(const struct sock *sk,
160 struct user_namespace *user_ns, int cap)
161 {
162 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
163 ns_capable(user_ns, cap);
164 }
165 EXPORT_SYMBOL(sk_ns_capable);
166
167 /**
168 * sk_capable - Socket global capability test
169 * @sk: Socket to use a capability on or through
170 * @cap: The global capability to use
171 *
172 * Test to see if the opener of the socket had when the socket was
173 * created and the current process has the capability @cap in all user
174 * namespaces.
175 */
176 bool sk_capable(const struct sock *sk, int cap)
177 {
178 return sk_ns_capable(sk, &init_user_ns, cap);
179 }
180 EXPORT_SYMBOL(sk_capable);
181
182 /**
183 * sk_net_capable - Network namespace socket capability test
184 * @sk: Socket to use a capability on or through
185 * @cap: The capability to use
186 *
187 * Test to see if the opener of the socket had when the socket was created
188 * and the current process has the capability @cap over the network namespace
189 * the socket is a member of.
190 */
191 bool sk_net_capable(const struct sock *sk, int cap)
192 {
193 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
194 }
195 EXPORT_SYMBOL(sk_net_capable);
196
197
198 #ifdef CONFIG_MEMCG_KMEM
199 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
200 {
201 struct proto *proto;
202 int ret = 0;
203
204 mutex_lock(&proto_list_mutex);
205 list_for_each_entry(proto, &proto_list, node) {
206 if (proto->init_cgroup) {
207 ret = proto->init_cgroup(memcg, ss);
208 if (ret)
209 goto out;
210 }
211 }
212
213 mutex_unlock(&proto_list_mutex);
214 return ret;
215 out:
216 list_for_each_entry_continue_reverse(proto, &proto_list, node)
217 if (proto->destroy_cgroup)
218 proto->destroy_cgroup(memcg);
219 mutex_unlock(&proto_list_mutex);
220 return ret;
221 }
222
223 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
224 {
225 struct proto *proto;
226
227 mutex_lock(&proto_list_mutex);
228 list_for_each_entry_reverse(proto, &proto_list, node)
229 if (proto->destroy_cgroup)
230 proto->destroy_cgroup(memcg);
231 mutex_unlock(&proto_list_mutex);
232 }
233 #endif
234
235 /*
236 * Each address family might have different locking rules, so we have
237 * one slock key per address family:
238 */
239 static struct lock_class_key af_family_keys[AF_MAX];
240 static struct lock_class_key af_family_slock_keys[AF_MAX];
241
242 #if defined(CONFIG_MEMCG_KMEM)
243 struct static_key memcg_socket_limit_enabled;
244 EXPORT_SYMBOL(memcg_socket_limit_enabled);
245 #endif
246
247 /*
248 * Make lock validator output more readable. (we pre-construct these
249 * strings build-time, so that runtime initialization of socket
250 * locks is fast):
251 */
252 static const char *const af_family_key_strings[AF_MAX+1] = {
253 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
254 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
255 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
256 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
257 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
258 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
259 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
260 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
261 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
262 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
263 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
264 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
265 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
266 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
267 };
268 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
269 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
270 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
271 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
272 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
273 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
274 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
275 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
276 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
277 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
278 "slock-27" , "slock-28" , "slock-AF_CAN" ,
279 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
280 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
281 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
282 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
283 };
284 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
285 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
286 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
287 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
288 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
289 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
290 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
291 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
292 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
293 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
294 "clock-27" , "clock-28" , "clock-AF_CAN" ,
295 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
296 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
297 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
298 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
299 };
300
301 /*
302 * sk_callback_lock locking rules are per-address-family,
303 * so split the lock classes by using a per-AF key:
304 */
305 static struct lock_class_key af_callback_keys[AF_MAX];
306
307 /* Take into consideration the size of the struct sk_buff overhead in the
308 * determination of these values, since that is non-constant across
309 * platforms. This makes socket queueing behavior and performance
310 * not depend upon such differences.
311 */
312 #define _SK_MEM_PACKETS 256
313 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
314 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
315 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
316
317 /* Run time adjustable parameters. */
318 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
319 EXPORT_SYMBOL(sysctl_wmem_max);
320 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
321 EXPORT_SYMBOL(sysctl_rmem_max);
322 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
323 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
324
325 /* Maximal space eaten by iovec or ancillary data plus some space */
326 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
327 EXPORT_SYMBOL(sysctl_optmem_max);
328
329 int sysctl_tstamp_allow_data __read_mostly = 1;
330
331 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
332 EXPORT_SYMBOL_GPL(memalloc_socks);
333
334 /**
335 * sk_set_memalloc - sets %SOCK_MEMALLOC
336 * @sk: socket to set it on
337 *
338 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
339 * It's the responsibility of the admin to adjust min_free_kbytes
340 * to meet the requirements
341 */
342 void sk_set_memalloc(struct sock *sk)
343 {
344 sock_set_flag(sk, SOCK_MEMALLOC);
345 sk->sk_allocation |= __GFP_MEMALLOC;
346 static_key_slow_inc(&memalloc_socks);
347 }
348 EXPORT_SYMBOL_GPL(sk_set_memalloc);
349
350 void sk_clear_memalloc(struct sock *sk)
351 {
352 sock_reset_flag(sk, SOCK_MEMALLOC);
353 sk->sk_allocation &= ~__GFP_MEMALLOC;
354 static_key_slow_dec(&memalloc_socks);
355
356 /*
357 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
358 * progress of swapping. SOCK_MEMALLOC may be cleared while
359 * it has rmem allocations due to the last swapfile being deactivated
360 * but there is a risk that the socket is unusable due to exceeding
361 * the rmem limits. Reclaim the reserves and obey rmem limits again.
362 */
363 sk_mem_reclaim(sk);
364 }
365 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
366
367 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
368 {
369 int ret;
370 unsigned long pflags = current->flags;
371
372 /* these should have been dropped before queueing */
373 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
374
375 current->flags |= PF_MEMALLOC;
376 ret = sk->sk_backlog_rcv(sk, skb);
377 tsk_restore_flags(current, pflags, PF_MEMALLOC);
378
379 return ret;
380 }
381 EXPORT_SYMBOL(__sk_backlog_rcv);
382
383 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
384 {
385 struct timeval tv;
386
387 if (optlen < sizeof(tv))
388 return -EINVAL;
389 if (copy_from_user(&tv, optval, sizeof(tv)))
390 return -EFAULT;
391 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
392 return -EDOM;
393
394 if (tv.tv_sec < 0) {
395 static int warned __read_mostly;
396
397 *timeo_p = 0;
398 if (warned < 10 && net_ratelimit()) {
399 warned++;
400 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
401 __func__, current->comm, task_pid_nr(current));
402 }
403 return 0;
404 }
405 *timeo_p = MAX_SCHEDULE_TIMEOUT;
406 if (tv.tv_sec == 0 && tv.tv_usec == 0)
407 return 0;
408 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
409 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
410 return 0;
411 }
412
413 static void sock_warn_obsolete_bsdism(const char *name)
414 {
415 static int warned;
416 static char warncomm[TASK_COMM_LEN];
417 if (strcmp(warncomm, current->comm) && warned < 5) {
418 strcpy(warncomm, current->comm);
419 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
420 warncomm, name);
421 warned++;
422 }
423 }
424
425 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
426
427 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
428 {
429 if (sk->sk_flags & flags) {
430 sk->sk_flags &= ~flags;
431 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
432 net_disable_timestamp();
433 }
434 }
435
436
437 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
438 {
439 int err;
440 unsigned long flags;
441 struct sk_buff_head *list = &sk->sk_receive_queue;
442
443 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
444 atomic_inc(&sk->sk_drops);
445 trace_sock_rcvqueue_full(sk, skb);
446 return -ENOMEM;
447 }
448
449 err = sk_filter(sk, skb);
450 if (err)
451 return err;
452
453 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
454 atomic_inc(&sk->sk_drops);
455 return -ENOBUFS;
456 }
457
458 skb->dev = NULL;
459 skb_set_owner_r(skb, sk);
460
461 /* we escape from rcu protected region, make sure we dont leak
462 * a norefcounted dst
463 */
464 skb_dst_force(skb);
465
466 spin_lock_irqsave(&list->lock, flags);
467 sock_skb_set_dropcount(sk, skb);
468 __skb_queue_tail(list, skb);
469 spin_unlock_irqrestore(&list->lock, flags);
470
471 if (!sock_flag(sk, SOCK_DEAD))
472 sk->sk_data_ready(sk);
473 return 0;
474 }
475 EXPORT_SYMBOL(sock_queue_rcv_skb);
476
477 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
478 {
479 int rc = NET_RX_SUCCESS;
480
481 if (sk_filter(sk, skb))
482 goto discard_and_relse;
483
484 skb->dev = NULL;
485
486 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
487 atomic_inc(&sk->sk_drops);
488 goto discard_and_relse;
489 }
490 if (nested)
491 bh_lock_sock_nested(sk);
492 else
493 bh_lock_sock(sk);
494 if (!sock_owned_by_user(sk)) {
495 /*
496 * trylock + unlock semantics:
497 */
498 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
499
500 rc = sk_backlog_rcv(sk, skb);
501
502 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
503 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
504 bh_unlock_sock(sk);
505 atomic_inc(&sk->sk_drops);
506 goto discard_and_relse;
507 }
508
509 bh_unlock_sock(sk);
510 out:
511 sock_put(sk);
512 return rc;
513 discard_and_relse:
514 kfree_skb(skb);
515 goto out;
516 }
517 EXPORT_SYMBOL(sk_receive_skb);
518
519 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
520 {
521 struct dst_entry *dst = __sk_dst_get(sk);
522
523 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
524 sk_tx_queue_clear(sk);
525 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
526 dst_release(dst);
527 return NULL;
528 }
529
530 return dst;
531 }
532 EXPORT_SYMBOL(__sk_dst_check);
533
534 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
535 {
536 struct dst_entry *dst = sk_dst_get(sk);
537
538 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
539 sk_dst_reset(sk);
540 dst_release(dst);
541 return NULL;
542 }
543
544 return dst;
545 }
546 EXPORT_SYMBOL(sk_dst_check);
547
548 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
549 int optlen)
550 {
551 int ret = -ENOPROTOOPT;
552 #ifdef CONFIG_NETDEVICES
553 struct net *net = sock_net(sk);
554 char devname[IFNAMSIZ];
555 int index;
556
557 /* Sorry... */
558 ret = -EPERM;
559 if (!ns_capable(net->user_ns, CAP_NET_RAW))
560 goto out;
561
562 ret = -EINVAL;
563 if (optlen < 0)
564 goto out;
565
566 /* Bind this socket to a particular device like "eth0",
567 * as specified in the passed interface name. If the
568 * name is "" or the option length is zero the socket
569 * is not bound.
570 */
571 if (optlen > IFNAMSIZ - 1)
572 optlen = IFNAMSIZ - 1;
573 memset(devname, 0, sizeof(devname));
574
575 ret = -EFAULT;
576 if (copy_from_user(devname, optval, optlen))
577 goto out;
578
579 index = 0;
580 if (devname[0] != '\0') {
581 struct net_device *dev;
582
583 rcu_read_lock();
584 dev = dev_get_by_name_rcu(net, devname);
585 if (dev)
586 index = dev->ifindex;
587 rcu_read_unlock();
588 ret = -ENODEV;
589 if (!dev)
590 goto out;
591 }
592
593 lock_sock(sk);
594 sk->sk_bound_dev_if = index;
595 sk_dst_reset(sk);
596 release_sock(sk);
597
598 ret = 0;
599
600 out:
601 #endif
602
603 return ret;
604 }
605
606 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
607 int __user *optlen, int len)
608 {
609 int ret = -ENOPROTOOPT;
610 #ifdef CONFIG_NETDEVICES
611 struct net *net = sock_net(sk);
612 char devname[IFNAMSIZ];
613
614 if (sk->sk_bound_dev_if == 0) {
615 len = 0;
616 goto zero;
617 }
618
619 ret = -EINVAL;
620 if (len < IFNAMSIZ)
621 goto out;
622
623 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
624 if (ret)
625 goto out;
626
627 len = strlen(devname) + 1;
628
629 ret = -EFAULT;
630 if (copy_to_user(optval, devname, len))
631 goto out;
632
633 zero:
634 ret = -EFAULT;
635 if (put_user(len, optlen))
636 goto out;
637
638 ret = 0;
639
640 out:
641 #endif
642
643 return ret;
644 }
645
646 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
647 {
648 if (valbool)
649 sock_set_flag(sk, bit);
650 else
651 sock_reset_flag(sk, bit);
652 }
653
654 bool sk_mc_loop(struct sock *sk)
655 {
656 if (dev_recursion_level())
657 return false;
658 if (!sk)
659 return true;
660 switch (sk->sk_family) {
661 case AF_INET:
662 return inet_sk(sk)->mc_loop;
663 #if IS_ENABLED(CONFIG_IPV6)
664 case AF_INET6:
665 return inet6_sk(sk)->mc_loop;
666 #endif
667 }
668 WARN_ON(1);
669 return true;
670 }
671 EXPORT_SYMBOL(sk_mc_loop);
672
673 /*
674 * This is meant for all protocols to use and covers goings on
675 * at the socket level. Everything here is generic.
676 */
677
678 int sock_setsockopt(struct socket *sock, int level, int optname,
679 char __user *optval, unsigned int optlen)
680 {
681 struct sock *sk = sock->sk;
682 int val;
683 int valbool;
684 struct linger ling;
685 int ret = 0;
686
687 /*
688 * Options without arguments
689 */
690
691 if (optname == SO_BINDTODEVICE)
692 return sock_setbindtodevice(sk, optval, optlen);
693
694 if (optlen < sizeof(int))
695 return -EINVAL;
696
697 if (get_user(val, (int __user *)optval))
698 return -EFAULT;
699
700 valbool = val ? 1 : 0;
701
702 lock_sock(sk);
703
704 switch (optname) {
705 case SO_DEBUG:
706 if (val && !capable(CAP_NET_ADMIN))
707 ret = -EACCES;
708 else
709 sock_valbool_flag(sk, SOCK_DBG, valbool);
710 break;
711 case SO_REUSEADDR:
712 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
713 break;
714 case SO_REUSEPORT:
715 sk->sk_reuseport = valbool;
716 break;
717 case SO_TYPE:
718 case SO_PROTOCOL:
719 case SO_DOMAIN:
720 case SO_ERROR:
721 ret = -ENOPROTOOPT;
722 break;
723 case SO_DONTROUTE:
724 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
725 break;
726 case SO_BROADCAST:
727 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
728 break;
729 case SO_SNDBUF:
730 /* Don't error on this BSD doesn't and if you think
731 * about it this is right. Otherwise apps have to
732 * play 'guess the biggest size' games. RCVBUF/SNDBUF
733 * are treated in BSD as hints
734 */
735 val = min_t(u32, val, sysctl_wmem_max);
736 set_sndbuf:
737 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
738 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
739 /* Wake up sending tasks if we upped the value. */
740 sk->sk_write_space(sk);
741 break;
742
743 case SO_SNDBUFFORCE:
744 if (!capable(CAP_NET_ADMIN)) {
745 ret = -EPERM;
746 break;
747 }
748 goto set_sndbuf;
749
750 case SO_RCVBUF:
751 /* Don't error on this BSD doesn't and if you think
752 * about it this is right. Otherwise apps have to
753 * play 'guess the biggest size' games. RCVBUF/SNDBUF
754 * are treated in BSD as hints
755 */
756 val = min_t(u32, val, sysctl_rmem_max);
757 set_rcvbuf:
758 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
759 /*
760 * We double it on the way in to account for
761 * "struct sk_buff" etc. overhead. Applications
762 * assume that the SO_RCVBUF setting they make will
763 * allow that much actual data to be received on that
764 * socket.
765 *
766 * Applications are unaware that "struct sk_buff" and
767 * other overheads allocate from the receive buffer
768 * during socket buffer allocation.
769 *
770 * And after considering the possible alternatives,
771 * returning the value we actually used in getsockopt
772 * is the most desirable behavior.
773 */
774 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
775 break;
776
777 case SO_RCVBUFFORCE:
778 if (!capable(CAP_NET_ADMIN)) {
779 ret = -EPERM;
780 break;
781 }
782 goto set_rcvbuf;
783
784 case SO_KEEPALIVE:
785 #ifdef CONFIG_INET
786 if (sk->sk_protocol == IPPROTO_TCP &&
787 sk->sk_type == SOCK_STREAM)
788 tcp_set_keepalive(sk, valbool);
789 #endif
790 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
791 break;
792
793 case SO_OOBINLINE:
794 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
795 break;
796
797 case SO_NO_CHECK:
798 sk->sk_no_check_tx = valbool;
799 break;
800
801 case SO_PRIORITY:
802 if ((val >= 0 && val <= 6) ||
803 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
804 sk->sk_priority = val;
805 else
806 ret = -EPERM;
807 break;
808
809 case SO_LINGER:
810 if (optlen < sizeof(ling)) {
811 ret = -EINVAL; /* 1003.1g */
812 break;
813 }
814 if (copy_from_user(&ling, optval, sizeof(ling))) {
815 ret = -EFAULT;
816 break;
817 }
818 if (!ling.l_onoff)
819 sock_reset_flag(sk, SOCK_LINGER);
820 else {
821 #if (BITS_PER_LONG == 32)
822 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
823 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
824 else
825 #endif
826 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
827 sock_set_flag(sk, SOCK_LINGER);
828 }
829 break;
830
831 case SO_BSDCOMPAT:
832 sock_warn_obsolete_bsdism("setsockopt");
833 break;
834
835 case SO_PASSCRED:
836 if (valbool)
837 set_bit(SOCK_PASSCRED, &sock->flags);
838 else
839 clear_bit(SOCK_PASSCRED, &sock->flags);
840 break;
841
842 case SO_TIMESTAMP:
843 case SO_TIMESTAMPNS:
844 if (valbool) {
845 if (optname == SO_TIMESTAMP)
846 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
847 else
848 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
849 sock_set_flag(sk, SOCK_RCVTSTAMP);
850 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
851 } else {
852 sock_reset_flag(sk, SOCK_RCVTSTAMP);
853 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
854 }
855 break;
856
857 case SO_TIMESTAMPING:
858 if (val & ~SOF_TIMESTAMPING_MASK) {
859 ret = -EINVAL;
860 break;
861 }
862
863 if (val & SOF_TIMESTAMPING_OPT_ID &&
864 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
865 if (sk->sk_protocol == IPPROTO_TCP) {
866 if (sk->sk_state != TCP_ESTABLISHED) {
867 ret = -EINVAL;
868 break;
869 }
870 sk->sk_tskey = tcp_sk(sk)->snd_una;
871 } else {
872 sk->sk_tskey = 0;
873 }
874 }
875 sk->sk_tsflags = val;
876 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
877 sock_enable_timestamp(sk,
878 SOCK_TIMESTAMPING_RX_SOFTWARE);
879 else
880 sock_disable_timestamp(sk,
881 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
882 break;
883
884 case SO_RCVLOWAT:
885 if (val < 0)
886 val = INT_MAX;
887 sk->sk_rcvlowat = val ? : 1;
888 break;
889
890 case SO_RCVTIMEO:
891 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
892 break;
893
894 case SO_SNDTIMEO:
895 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
896 break;
897
898 case SO_ATTACH_FILTER:
899 ret = -EINVAL;
900 if (optlen == sizeof(struct sock_fprog)) {
901 struct sock_fprog fprog;
902
903 ret = -EFAULT;
904 if (copy_from_user(&fprog, optval, sizeof(fprog)))
905 break;
906
907 ret = sk_attach_filter(&fprog, sk);
908 }
909 break;
910
911 case SO_ATTACH_BPF:
912 ret = -EINVAL;
913 if (optlen == sizeof(u32)) {
914 u32 ufd;
915
916 ret = -EFAULT;
917 if (copy_from_user(&ufd, optval, sizeof(ufd)))
918 break;
919
920 ret = sk_attach_bpf(ufd, sk);
921 }
922 break;
923
924 case SO_DETACH_FILTER:
925 ret = sk_detach_filter(sk);
926 break;
927
928 case SO_LOCK_FILTER:
929 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
930 ret = -EPERM;
931 else
932 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
933 break;
934
935 case SO_PASSSEC:
936 if (valbool)
937 set_bit(SOCK_PASSSEC, &sock->flags);
938 else
939 clear_bit(SOCK_PASSSEC, &sock->flags);
940 break;
941 case SO_MARK:
942 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
943 ret = -EPERM;
944 else
945 sk->sk_mark = val;
946 break;
947
948 case SO_RXQ_OVFL:
949 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
950 break;
951
952 case SO_WIFI_STATUS:
953 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
954 break;
955
956 case SO_PEEK_OFF:
957 if (sock->ops->set_peek_off)
958 ret = sock->ops->set_peek_off(sk, val);
959 else
960 ret = -EOPNOTSUPP;
961 break;
962
963 case SO_NOFCS:
964 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
965 break;
966
967 case SO_SELECT_ERR_QUEUE:
968 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
969 break;
970
971 #ifdef CONFIG_NET_RX_BUSY_POLL
972 case SO_BUSY_POLL:
973 /* allow unprivileged users to decrease the value */
974 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
975 ret = -EPERM;
976 else {
977 if (val < 0)
978 ret = -EINVAL;
979 else
980 sk->sk_ll_usec = val;
981 }
982 break;
983 #endif
984
985 case SO_MAX_PACING_RATE:
986 sk->sk_max_pacing_rate = val;
987 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
988 sk->sk_max_pacing_rate);
989 break;
990
991 default:
992 ret = -ENOPROTOOPT;
993 break;
994 }
995 release_sock(sk);
996 return ret;
997 }
998 EXPORT_SYMBOL(sock_setsockopt);
999
1000
1001 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1002 struct ucred *ucred)
1003 {
1004 ucred->pid = pid_vnr(pid);
1005 ucred->uid = ucred->gid = -1;
1006 if (cred) {
1007 struct user_namespace *current_ns = current_user_ns();
1008
1009 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1010 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1011 }
1012 }
1013
1014 int sock_getsockopt(struct socket *sock, int level, int optname,
1015 char __user *optval, int __user *optlen)
1016 {
1017 struct sock *sk = sock->sk;
1018
1019 union {
1020 int val;
1021 struct linger ling;
1022 struct timeval tm;
1023 } v;
1024
1025 int lv = sizeof(int);
1026 int len;
1027
1028 if (get_user(len, optlen))
1029 return -EFAULT;
1030 if (len < 0)
1031 return -EINVAL;
1032
1033 memset(&v, 0, sizeof(v));
1034
1035 switch (optname) {
1036 case SO_DEBUG:
1037 v.val = sock_flag(sk, SOCK_DBG);
1038 break;
1039
1040 case SO_DONTROUTE:
1041 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1042 break;
1043
1044 case SO_BROADCAST:
1045 v.val = sock_flag(sk, SOCK_BROADCAST);
1046 break;
1047
1048 case SO_SNDBUF:
1049 v.val = sk->sk_sndbuf;
1050 break;
1051
1052 case SO_RCVBUF:
1053 v.val = sk->sk_rcvbuf;
1054 break;
1055
1056 case SO_REUSEADDR:
1057 v.val = sk->sk_reuse;
1058 break;
1059
1060 case SO_REUSEPORT:
1061 v.val = sk->sk_reuseport;
1062 break;
1063
1064 case SO_KEEPALIVE:
1065 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1066 break;
1067
1068 case SO_TYPE:
1069 v.val = sk->sk_type;
1070 break;
1071
1072 case SO_PROTOCOL:
1073 v.val = sk->sk_protocol;
1074 break;
1075
1076 case SO_DOMAIN:
1077 v.val = sk->sk_family;
1078 break;
1079
1080 case SO_ERROR:
1081 v.val = -sock_error(sk);
1082 if (v.val == 0)
1083 v.val = xchg(&sk->sk_err_soft, 0);
1084 break;
1085
1086 case SO_OOBINLINE:
1087 v.val = sock_flag(sk, SOCK_URGINLINE);
1088 break;
1089
1090 case SO_NO_CHECK:
1091 v.val = sk->sk_no_check_tx;
1092 break;
1093
1094 case SO_PRIORITY:
1095 v.val = sk->sk_priority;
1096 break;
1097
1098 case SO_LINGER:
1099 lv = sizeof(v.ling);
1100 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1101 v.ling.l_linger = sk->sk_lingertime / HZ;
1102 break;
1103
1104 case SO_BSDCOMPAT:
1105 sock_warn_obsolete_bsdism("getsockopt");
1106 break;
1107
1108 case SO_TIMESTAMP:
1109 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1110 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1111 break;
1112
1113 case SO_TIMESTAMPNS:
1114 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1115 break;
1116
1117 case SO_TIMESTAMPING:
1118 v.val = sk->sk_tsflags;
1119 break;
1120
1121 case SO_RCVTIMEO:
1122 lv = sizeof(struct timeval);
1123 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1124 v.tm.tv_sec = 0;
1125 v.tm.tv_usec = 0;
1126 } else {
1127 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1128 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1129 }
1130 break;
1131
1132 case SO_SNDTIMEO:
1133 lv = sizeof(struct timeval);
1134 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1135 v.tm.tv_sec = 0;
1136 v.tm.tv_usec = 0;
1137 } else {
1138 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1139 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1140 }
1141 break;
1142
1143 case SO_RCVLOWAT:
1144 v.val = sk->sk_rcvlowat;
1145 break;
1146
1147 case SO_SNDLOWAT:
1148 v.val = 1;
1149 break;
1150
1151 case SO_PASSCRED:
1152 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1153 break;
1154
1155 case SO_PEERCRED:
1156 {
1157 struct ucred peercred;
1158 if (len > sizeof(peercred))
1159 len = sizeof(peercred);
1160 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1161 if (copy_to_user(optval, &peercred, len))
1162 return -EFAULT;
1163 goto lenout;
1164 }
1165
1166 case SO_PEERNAME:
1167 {
1168 char address[128];
1169
1170 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1171 return -ENOTCONN;
1172 if (lv < len)
1173 return -EINVAL;
1174 if (copy_to_user(optval, address, len))
1175 return -EFAULT;
1176 goto lenout;
1177 }
1178
1179 /* Dubious BSD thing... Probably nobody even uses it, but
1180 * the UNIX standard wants it for whatever reason... -DaveM
1181 */
1182 case SO_ACCEPTCONN:
1183 v.val = sk->sk_state == TCP_LISTEN;
1184 break;
1185
1186 case SO_PASSSEC:
1187 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1188 break;
1189
1190 case SO_PEERSEC:
1191 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1192
1193 case SO_MARK:
1194 v.val = sk->sk_mark;
1195 break;
1196
1197 case SO_RXQ_OVFL:
1198 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1199 break;
1200
1201 case SO_WIFI_STATUS:
1202 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1203 break;
1204
1205 case SO_PEEK_OFF:
1206 if (!sock->ops->set_peek_off)
1207 return -EOPNOTSUPP;
1208
1209 v.val = sk->sk_peek_off;
1210 break;
1211 case SO_NOFCS:
1212 v.val = sock_flag(sk, SOCK_NOFCS);
1213 break;
1214
1215 case SO_BINDTODEVICE:
1216 return sock_getbindtodevice(sk, optval, optlen, len);
1217
1218 case SO_GET_FILTER:
1219 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1220 if (len < 0)
1221 return len;
1222
1223 goto lenout;
1224
1225 case SO_LOCK_FILTER:
1226 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1227 break;
1228
1229 case SO_BPF_EXTENSIONS:
1230 v.val = bpf_tell_extensions();
1231 break;
1232
1233 case SO_SELECT_ERR_QUEUE:
1234 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1235 break;
1236
1237 #ifdef CONFIG_NET_RX_BUSY_POLL
1238 case SO_BUSY_POLL:
1239 v.val = sk->sk_ll_usec;
1240 break;
1241 #endif
1242
1243 case SO_MAX_PACING_RATE:
1244 v.val = sk->sk_max_pacing_rate;
1245 break;
1246
1247 case SO_INCOMING_CPU:
1248 v.val = sk->sk_incoming_cpu;
1249 break;
1250
1251 default:
1252 /* We implement the SO_SNDLOWAT etc to not be settable
1253 * (1003.1g 7).
1254 */
1255 return -ENOPROTOOPT;
1256 }
1257
1258 if (len > lv)
1259 len = lv;
1260 if (copy_to_user(optval, &v, len))
1261 return -EFAULT;
1262 lenout:
1263 if (put_user(len, optlen))
1264 return -EFAULT;
1265 return 0;
1266 }
1267
1268 /*
1269 * Initialize an sk_lock.
1270 *
1271 * (We also register the sk_lock with the lock validator.)
1272 */
1273 static inline void sock_lock_init(struct sock *sk)
1274 {
1275 sock_lock_init_class_and_name(sk,
1276 af_family_slock_key_strings[sk->sk_family],
1277 af_family_slock_keys + sk->sk_family,
1278 af_family_key_strings[sk->sk_family],
1279 af_family_keys + sk->sk_family);
1280 }
1281
1282 /*
1283 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1284 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1285 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1286 */
1287 static void sock_copy(struct sock *nsk, const struct sock *osk)
1288 {
1289 #ifdef CONFIG_SECURITY_NETWORK
1290 void *sptr = nsk->sk_security;
1291 #endif
1292 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1293
1294 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1295 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1296
1297 #ifdef CONFIG_SECURITY_NETWORK
1298 nsk->sk_security = sptr;
1299 security_sk_clone(osk, nsk);
1300 #endif
1301 }
1302
1303 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1304 {
1305 unsigned long nulls1, nulls2;
1306
1307 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1308 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1309 if (nulls1 > nulls2)
1310 swap(nulls1, nulls2);
1311
1312 if (nulls1 != 0)
1313 memset((char *)sk, 0, nulls1);
1314 memset((char *)sk + nulls1 + sizeof(void *), 0,
1315 nulls2 - nulls1 - sizeof(void *));
1316 memset((char *)sk + nulls2 + sizeof(void *), 0,
1317 size - nulls2 - sizeof(void *));
1318 }
1319 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1320
1321 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1322 int family)
1323 {
1324 struct sock *sk;
1325 struct kmem_cache *slab;
1326
1327 slab = prot->slab;
1328 if (slab != NULL) {
1329 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1330 if (!sk)
1331 return sk;
1332 if (priority & __GFP_ZERO) {
1333 if (prot->clear_sk)
1334 prot->clear_sk(sk, prot->obj_size);
1335 else
1336 sk_prot_clear_nulls(sk, prot->obj_size);
1337 }
1338 } else
1339 sk = kmalloc(prot->obj_size, priority);
1340
1341 if (sk != NULL) {
1342 kmemcheck_annotate_bitfield(sk, flags);
1343
1344 if (security_sk_alloc(sk, family, priority))
1345 goto out_free;
1346
1347 if (!try_module_get(prot->owner))
1348 goto out_free_sec;
1349 sk_tx_queue_clear(sk);
1350 }
1351
1352 return sk;
1353
1354 out_free_sec:
1355 security_sk_free(sk);
1356 out_free:
1357 if (slab != NULL)
1358 kmem_cache_free(slab, sk);
1359 else
1360 kfree(sk);
1361 return NULL;
1362 }
1363
1364 static void sk_prot_free(struct proto *prot, struct sock *sk)
1365 {
1366 struct kmem_cache *slab;
1367 struct module *owner;
1368
1369 owner = prot->owner;
1370 slab = prot->slab;
1371
1372 security_sk_free(sk);
1373 if (slab != NULL)
1374 kmem_cache_free(slab, sk);
1375 else
1376 kfree(sk);
1377 module_put(owner);
1378 }
1379
1380 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
1381 void sock_update_netprioidx(struct sock *sk)
1382 {
1383 if (in_interrupt())
1384 return;
1385
1386 sk->sk_cgrp_prioidx = task_netprioidx(current);
1387 }
1388 EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1389 #endif
1390
1391 /**
1392 * sk_alloc - All socket objects are allocated here
1393 * @net: the applicable net namespace
1394 * @family: protocol family
1395 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1396 * @prot: struct proto associated with this new sock instance
1397 * @kern: is this to be a kernel socket?
1398 */
1399 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1400 struct proto *prot, int kern)
1401 {
1402 struct sock *sk;
1403
1404 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1405 if (sk) {
1406 sk->sk_family = family;
1407 /*
1408 * See comment in struct sock definition to understand
1409 * why we need sk_prot_creator -acme
1410 */
1411 sk->sk_prot = sk->sk_prot_creator = prot;
1412 sock_lock_init(sk);
1413 sk->sk_net_refcnt = kern ? 0 : 1;
1414 if (likely(sk->sk_net_refcnt))
1415 get_net(net);
1416 sock_net_set(sk, net);
1417 atomic_set(&sk->sk_wmem_alloc, 1);
1418
1419 sock_update_classid(sk);
1420 sock_update_netprioidx(sk);
1421 }
1422
1423 return sk;
1424 }
1425 EXPORT_SYMBOL(sk_alloc);
1426
1427 void sk_destruct(struct sock *sk)
1428 {
1429 struct sk_filter *filter;
1430
1431 if (sk->sk_destruct)
1432 sk->sk_destruct(sk);
1433
1434 filter = rcu_dereference_check(sk->sk_filter,
1435 atomic_read(&sk->sk_wmem_alloc) == 0);
1436 if (filter) {
1437 sk_filter_uncharge(sk, filter);
1438 RCU_INIT_POINTER(sk->sk_filter, NULL);
1439 }
1440
1441 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1442
1443 if (atomic_read(&sk->sk_omem_alloc))
1444 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1445 __func__, atomic_read(&sk->sk_omem_alloc));
1446
1447 if (sk->sk_peer_cred)
1448 put_cred(sk->sk_peer_cred);
1449 put_pid(sk->sk_peer_pid);
1450 if (likely(sk->sk_net_refcnt))
1451 put_net(sock_net(sk));
1452 sk_prot_free(sk->sk_prot_creator, sk);
1453 }
1454
1455 static void __sk_free(struct sock *sk)
1456 {
1457 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1458 sock_diag_broadcast_destroy(sk);
1459 else
1460 sk_destruct(sk);
1461 }
1462
1463 void sk_free(struct sock *sk)
1464 {
1465 /*
1466 * We subtract one from sk_wmem_alloc and can know if
1467 * some packets are still in some tx queue.
1468 * If not null, sock_wfree() will call __sk_free(sk) later
1469 */
1470 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1471 __sk_free(sk);
1472 }
1473 EXPORT_SYMBOL(sk_free);
1474
1475 static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1476 {
1477 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1478 sock_update_memcg(newsk);
1479 }
1480
1481 /**
1482 * sk_clone_lock - clone a socket, and lock its clone
1483 * @sk: the socket to clone
1484 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1485 *
1486 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1487 */
1488 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1489 {
1490 struct sock *newsk;
1491 bool is_charged = true;
1492
1493 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1494 if (newsk != NULL) {
1495 struct sk_filter *filter;
1496
1497 sock_copy(newsk, sk);
1498
1499 /* SANITY */
1500 get_net(sock_net(newsk));
1501 sk_node_init(&newsk->sk_node);
1502 sock_lock_init(newsk);
1503 bh_lock_sock(newsk);
1504 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1505 newsk->sk_backlog.len = 0;
1506
1507 atomic_set(&newsk->sk_rmem_alloc, 0);
1508 /*
1509 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1510 */
1511 atomic_set(&newsk->sk_wmem_alloc, 1);
1512 atomic_set(&newsk->sk_omem_alloc, 0);
1513 skb_queue_head_init(&newsk->sk_receive_queue);
1514 skb_queue_head_init(&newsk->sk_write_queue);
1515
1516 spin_lock_init(&newsk->sk_dst_lock);
1517 rwlock_init(&newsk->sk_callback_lock);
1518 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1519 af_callback_keys + newsk->sk_family,
1520 af_family_clock_key_strings[newsk->sk_family]);
1521
1522 newsk->sk_dst_cache = NULL;
1523 newsk->sk_wmem_queued = 0;
1524 newsk->sk_forward_alloc = 0;
1525 newsk->sk_send_head = NULL;
1526 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1527
1528 sock_reset_flag(newsk, SOCK_DONE);
1529 skb_queue_head_init(&newsk->sk_error_queue);
1530
1531 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1532 if (filter != NULL)
1533 /* though it's an empty new sock, the charging may fail
1534 * if sysctl_optmem_max was changed between creation of
1535 * original socket and cloning
1536 */
1537 is_charged = sk_filter_charge(newsk, filter);
1538
1539 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) {
1540 /* It is still raw copy of parent, so invalidate
1541 * destructor and make plain sk_free() */
1542 newsk->sk_destruct = NULL;
1543 bh_unlock_sock(newsk);
1544 sk_free(newsk);
1545 newsk = NULL;
1546 goto out;
1547 }
1548
1549 newsk->sk_err = 0;
1550 newsk->sk_priority = 0;
1551 newsk->sk_incoming_cpu = raw_smp_processor_id();
1552 atomic64_set(&newsk->sk_cookie, 0);
1553 /*
1554 * Before updating sk_refcnt, we must commit prior changes to memory
1555 * (Documentation/RCU/rculist_nulls.txt for details)
1556 */
1557 smp_wmb();
1558 atomic_set(&newsk->sk_refcnt, 2);
1559
1560 /*
1561 * Increment the counter in the same struct proto as the master
1562 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1563 * is the same as sk->sk_prot->socks, as this field was copied
1564 * with memcpy).
1565 *
1566 * This _changes_ the previous behaviour, where
1567 * tcp_create_openreq_child always was incrementing the
1568 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1569 * to be taken into account in all callers. -acme
1570 */
1571 sk_refcnt_debug_inc(newsk);
1572 sk_set_socket(newsk, NULL);
1573 newsk->sk_wq = NULL;
1574
1575 sk_update_clone(sk, newsk);
1576
1577 if (newsk->sk_prot->sockets_allocated)
1578 sk_sockets_allocated_inc(newsk);
1579
1580 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1581 net_enable_timestamp();
1582 }
1583 out:
1584 return newsk;
1585 }
1586 EXPORT_SYMBOL_GPL(sk_clone_lock);
1587
1588 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1589 {
1590 u32 max_segs = 1;
1591
1592 __sk_dst_set(sk, dst);
1593 sk->sk_route_caps = dst->dev->features;
1594 if (sk->sk_route_caps & NETIF_F_GSO)
1595 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1596 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1597 if (sk_can_gso(sk)) {
1598 if (dst->header_len) {
1599 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1600 } else {
1601 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1602 sk->sk_gso_max_size = dst->dev->gso_max_size;
1603 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1604 }
1605 }
1606 sk->sk_gso_max_segs = max_segs;
1607 }
1608 EXPORT_SYMBOL_GPL(sk_setup_caps);
1609
1610 /*
1611 * Simple resource managers for sockets.
1612 */
1613
1614
1615 /*
1616 * Write buffer destructor automatically called from kfree_skb.
1617 */
1618 void sock_wfree(struct sk_buff *skb)
1619 {
1620 struct sock *sk = skb->sk;
1621 unsigned int len = skb->truesize;
1622
1623 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1624 /*
1625 * Keep a reference on sk_wmem_alloc, this will be released
1626 * after sk_write_space() call
1627 */
1628 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1629 sk->sk_write_space(sk);
1630 len = 1;
1631 }
1632 /*
1633 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1634 * could not do because of in-flight packets
1635 */
1636 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1637 __sk_free(sk);
1638 }
1639 EXPORT_SYMBOL(sock_wfree);
1640
1641 void skb_orphan_partial(struct sk_buff *skb)
1642 {
1643 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1644 * so we do not completely orphan skb, but transfert all
1645 * accounted bytes but one, to avoid unexpected reorders.
1646 */
1647 if (skb->destructor == sock_wfree
1648 #ifdef CONFIG_INET
1649 || skb->destructor == tcp_wfree
1650 #endif
1651 ) {
1652 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1653 skb->truesize = 1;
1654 } else {
1655 skb_orphan(skb);
1656 }
1657 }
1658 EXPORT_SYMBOL(skb_orphan_partial);
1659
1660 /*
1661 * Read buffer destructor automatically called from kfree_skb.
1662 */
1663 void sock_rfree(struct sk_buff *skb)
1664 {
1665 struct sock *sk = skb->sk;
1666 unsigned int len = skb->truesize;
1667
1668 atomic_sub(len, &sk->sk_rmem_alloc);
1669 sk_mem_uncharge(sk, len);
1670 }
1671 EXPORT_SYMBOL(sock_rfree);
1672
1673 /*
1674 * Buffer destructor for skbs that are not used directly in read or write
1675 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1676 */
1677 void sock_efree(struct sk_buff *skb)
1678 {
1679 sock_put(skb->sk);
1680 }
1681 EXPORT_SYMBOL(sock_efree);
1682
1683 kuid_t sock_i_uid(struct sock *sk)
1684 {
1685 kuid_t uid;
1686
1687 read_lock_bh(&sk->sk_callback_lock);
1688 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1689 read_unlock_bh(&sk->sk_callback_lock);
1690 return uid;
1691 }
1692 EXPORT_SYMBOL(sock_i_uid);
1693
1694 unsigned long sock_i_ino(struct sock *sk)
1695 {
1696 unsigned long ino;
1697
1698 read_lock_bh(&sk->sk_callback_lock);
1699 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1700 read_unlock_bh(&sk->sk_callback_lock);
1701 return ino;
1702 }
1703 EXPORT_SYMBOL(sock_i_ino);
1704
1705 /*
1706 * Allocate a skb from the socket's send buffer.
1707 */
1708 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1709 gfp_t priority)
1710 {
1711 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1712 struct sk_buff *skb = alloc_skb(size, priority);
1713 if (skb) {
1714 skb_set_owner_w(skb, sk);
1715 return skb;
1716 }
1717 }
1718 return NULL;
1719 }
1720 EXPORT_SYMBOL(sock_wmalloc);
1721
1722 /*
1723 * Allocate a memory block from the socket's option memory buffer.
1724 */
1725 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1726 {
1727 if ((unsigned int)size <= sysctl_optmem_max &&
1728 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1729 void *mem;
1730 /* First do the add, to avoid the race if kmalloc
1731 * might sleep.
1732 */
1733 atomic_add(size, &sk->sk_omem_alloc);
1734 mem = kmalloc(size, priority);
1735 if (mem)
1736 return mem;
1737 atomic_sub(size, &sk->sk_omem_alloc);
1738 }
1739 return NULL;
1740 }
1741 EXPORT_SYMBOL(sock_kmalloc);
1742
1743 /* Free an option memory block. Note, we actually want the inline
1744 * here as this allows gcc to detect the nullify and fold away the
1745 * condition entirely.
1746 */
1747 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1748 const bool nullify)
1749 {
1750 if (WARN_ON_ONCE(!mem))
1751 return;
1752 if (nullify)
1753 kzfree(mem);
1754 else
1755 kfree(mem);
1756 atomic_sub(size, &sk->sk_omem_alloc);
1757 }
1758
1759 void sock_kfree_s(struct sock *sk, void *mem, int size)
1760 {
1761 __sock_kfree_s(sk, mem, size, false);
1762 }
1763 EXPORT_SYMBOL(sock_kfree_s);
1764
1765 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1766 {
1767 __sock_kfree_s(sk, mem, size, true);
1768 }
1769 EXPORT_SYMBOL(sock_kzfree_s);
1770
1771 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1772 I think, these locks should be removed for datagram sockets.
1773 */
1774 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1775 {
1776 DEFINE_WAIT(wait);
1777
1778 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1779 for (;;) {
1780 if (!timeo)
1781 break;
1782 if (signal_pending(current))
1783 break;
1784 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1785 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1786 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1787 break;
1788 if (sk->sk_shutdown & SEND_SHUTDOWN)
1789 break;
1790 if (sk->sk_err)
1791 break;
1792 timeo = schedule_timeout(timeo);
1793 }
1794 finish_wait(sk_sleep(sk), &wait);
1795 return timeo;
1796 }
1797
1798
1799 /*
1800 * Generic send/receive buffer handlers
1801 */
1802
1803 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1804 unsigned long data_len, int noblock,
1805 int *errcode, int max_page_order)
1806 {
1807 struct sk_buff *skb;
1808 long timeo;
1809 int err;
1810
1811 timeo = sock_sndtimeo(sk, noblock);
1812 for (;;) {
1813 err = sock_error(sk);
1814 if (err != 0)
1815 goto failure;
1816
1817 err = -EPIPE;
1818 if (sk->sk_shutdown & SEND_SHUTDOWN)
1819 goto failure;
1820
1821 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1822 break;
1823
1824 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1825 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1826 err = -EAGAIN;
1827 if (!timeo)
1828 goto failure;
1829 if (signal_pending(current))
1830 goto interrupted;
1831 timeo = sock_wait_for_wmem(sk, timeo);
1832 }
1833 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1834 errcode, sk->sk_allocation);
1835 if (skb)
1836 skb_set_owner_w(skb, sk);
1837 return skb;
1838
1839 interrupted:
1840 err = sock_intr_errno(timeo);
1841 failure:
1842 *errcode = err;
1843 return NULL;
1844 }
1845 EXPORT_SYMBOL(sock_alloc_send_pskb);
1846
1847 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1848 int noblock, int *errcode)
1849 {
1850 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1851 }
1852 EXPORT_SYMBOL(sock_alloc_send_skb);
1853
1854 /* On 32bit arches, an skb frag is limited to 2^15 */
1855 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1856
1857 /**
1858 * skb_page_frag_refill - check that a page_frag contains enough room
1859 * @sz: minimum size of the fragment we want to get
1860 * @pfrag: pointer to page_frag
1861 * @gfp: priority for memory allocation
1862 *
1863 * Note: While this allocator tries to use high order pages, there is
1864 * no guarantee that allocations succeed. Therefore, @sz MUST be
1865 * less or equal than PAGE_SIZE.
1866 */
1867 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1868 {
1869 if (pfrag->page) {
1870 if (atomic_read(&pfrag->page->_count) == 1) {
1871 pfrag->offset = 0;
1872 return true;
1873 }
1874 if (pfrag->offset + sz <= pfrag->size)
1875 return true;
1876 put_page(pfrag->page);
1877 }
1878
1879 pfrag->offset = 0;
1880 if (SKB_FRAG_PAGE_ORDER) {
1881 pfrag->page = alloc_pages((gfp & ~__GFP_WAIT) | __GFP_COMP |
1882 __GFP_NOWARN | __GFP_NORETRY,
1883 SKB_FRAG_PAGE_ORDER);
1884 if (likely(pfrag->page)) {
1885 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1886 return true;
1887 }
1888 }
1889 pfrag->page = alloc_page(gfp);
1890 if (likely(pfrag->page)) {
1891 pfrag->size = PAGE_SIZE;
1892 return true;
1893 }
1894 return false;
1895 }
1896 EXPORT_SYMBOL(skb_page_frag_refill);
1897
1898 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1899 {
1900 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1901 return true;
1902
1903 sk_enter_memory_pressure(sk);
1904 sk_stream_moderate_sndbuf(sk);
1905 return false;
1906 }
1907 EXPORT_SYMBOL(sk_page_frag_refill);
1908
1909 static void __lock_sock(struct sock *sk)
1910 __releases(&sk->sk_lock.slock)
1911 __acquires(&sk->sk_lock.slock)
1912 {
1913 DEFINE_WAIT(wait);
1914
1915 for (;;) {
1916 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1917 TASK_UNINTERRUPTIBLE);
1918 spin_unlock_bh(&sk->sk_lock.slock);
1919 schedule();
1920 spin_lock_bh(&sk->sk_lock.slock);
1921 if (!sock_owned_by_user(sk))
1922 break;
1923 }
1924 finish_wait(&sk->sk_lock.wq, &wait);
1925 }
1926
1927 static void __release_sock(struct sock *sk)
1928 __releases(&sk->sk_lock.slock)
1929 __acquires(&sk->sk_lock.slock)
1930 {
1931 struct sk_buff *skb = sk->sk_backlog.head;
1932
1933 do {
1934 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1935 bh_unlock_sock(sk);
1936
1937 do {
1938 struct sk_buff *next = skb->next;
1939
1940 prefetch(next);
1941 WARN_ON_ONCE(skb_dst_is_noref(skb));
1942 skb->next = NULL;
1943 sk_backlog_rcv(sk, skb);
1944
1945 /*
1946 * We are in process context here with softirqs
1947 * disabled, use cond_resched_softirq() to preempt.
1948 * This is safe to do because we've taken the backlog
1949 * queue private:
1950 */
1951 cond_resched_softirq();
1952
1953 skb = next;
1954 } while (skb != NULL);
1955
1956 bh_lock_sock(sk);
1957 } while ((skb = sk->sk_backlog.head) != NULL);
1958
1959 /*
1960 * Doing the zeroing here guarantee we can not loop forever
1961 * while a wild producer attempts to flood us.
1962 */
1963 sk->sk_backlog.len = 0;
1964 }
1965
1966 /**
1967 * sk_wait_data - wait for data to arrive at sk_receive_queue
1968 * @sk: sock to wait on
1969 * @timeo: for how long
1970 *
1971 * Now socket state including sk->sk_err is changed only under lock,
1972 * hence we may omit checks after joining wait queue.
1973 * We check receive queue before schedule() only as optimization;
1974 * it is very likely that release_sock() added new data.
1975 */
1976 int sk_wait_data(struct sock *sk, long *timeo)
1977 {
1978 int rc;
1979 DEFINE_WAIT(wait);
1980
1981 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1982 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1983 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1984 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1985 finish_wait(sk_sleep(sk), &wait);
1986 return rc;
1987 }
1988 EXPORT_SYMBOL(sk_wait_data);
1989
1990 /**
1991 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1992 * @sk: socket
1993 * @size: memory size to allocate
1994 * @kind: allocation type
1995 *
1996 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1997 * rmem allocation. This function assumes that protocols which have
1998 * memory_pressure use sk_wmem_queued as write buffer accounting.
1999 */
2000 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2001 {
2002 struct proto *prot = sk->sk_prot;
2003 int amt = sk_mem_pages(size);
2004 long allocated;
2005 int parent_status = UNDER_LIMIT;
2006
2007 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2008
2009 allocated = sk_memory_allocated_add(sk, amt, &parent_status);
2010
2011 /* Under limit. */
2012 if (parent_status == UNDER_LIMIT &&
2013 allocated <= sk_prot_mem_limits(sk, 0)) {
2014 sk_leave_memory_pressure(sk);
2015 return 1;
2016 }
2017
2018 /* Under pressure. (we or our parents) */
2019 if ((parent_status > SOFT_LIMIT) ||
2020 allocated > sk_prot_mem_limits(sk, 1))
2021 sk_enter_memory_pressure(sk);
2022
2023 /* Over hard limit (we or our parents) */
2024 if ((parent_status == OVER_LIMIT) ||
2025 (allocated > sk_prot_mem_limits(sk, 2)))
2026 goto suppress_allocation;
2027
2028 /* guarantee minimum buffer size under pressure */
2029 if (kind == SK_MEM_RECV) {
2030 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2031 return 1;
2032
2033 } else { /* SK_MEM_SEND */
2034 if (sk->sk_type == SOCK_STREAM) {
2035 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2036 return 1;
2037 } else if (atomic_read(&sk->sk_wmem_alloc) <
2038 prot->sysctl_wmem[0])
2039 return 1;
2040 }
2041
2042 if (sk_has_memory_pressure(sk)) {
2043 int alloc;
2044
2045 if (!sk_under_memory_pressure(sk))
2046 return 1;
2047 alloc = sk_sockets_allocated_read_positive(sk);
2048 if (sk_prot_mem_limits(sk, 2) > alloc *
2049 sk_mem_pages(sk->sk_wmem_queued +
2050 atomic_read(&sk->sk_rmem_alloc) +
2051 sk->sk_forward_alloc))
2052 return 1;
2053 }
2054
2055 suppress_allocation:
2056
2057 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2058 sk_stream_moderate_sndbuf(sk);
2059
2060 /* Fail only if socket is _under_ its sndbuf.
2061 * In this case we cannot block, so that we have to fail.
2062 */
2063 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2064 return 1;
2065 }
2066
2067 trace_sock_exceed_buf_limit(sk, prot, allocated);
2068
2069 /* Alas. Undo changes. */
2070 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2071
2072 sk_memory_allocated_sub(sk, amt);
2073
2074 return 0;
2075 }
2076 EXPORT_SYMBOL(__sk_mem_schedule);
2077
2078 /**
2079 * __sk_reclaim - reclaim memory_allocated
2080 * @sk: socket
2081 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2082 */
2083 void __sk_mem_reclaim(struct sock *sk, int amount)
2084 {
2085 amount >>= SK_MEM_QUANTUM_SHIFT;
2086 sk_memory_allocated_sub(sk, amount);
2087 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2088
2089 if (sk_under_memory_pressure(sk) &&
2090 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2091 sk_leave_memory_pressure(sk);
2092 }
2093 EXPORT_SYMBOL(__sk_mem_reclaim);
2094
2095
2096 /*
2097 * Set of default routines for initialising struct proto_ops when
2098 * the protocol does not support a particular function. In certain
2099 * cases where it makes no sense for a protocol to have a "do nothing"
2100 * function, some default processing is provided.
2101 */
2102
2103 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2104 {
2105 return -EOPNOTSUPP;
2106 }
2107 EXPORT_SYMBOL(sock_no_bind);
2108
2109 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2110 int len, int flags)
2111 {
2112 return -EOPNOTSUPP;
2113 }
2114 EXPORT_SYMBOL(sock_no_connect);
2115
2116 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2117 {
2118 return -EOPNOTSUPP;
2119 }
2120 EXPORT_SYMBOL(sock_no_socketpair);
2121
2122 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2123 {
2124 return -EOPNOTSUPP;
2125 }
2126 EXPORT_SYMBOL(sock_no_accept);
2127
2128 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2129 int *len, int peer)
2130 {
2131 return -EOPNOTSUPP;
2132 }
2133 EXPORT_SYMBOL(sock_no_getname);
2134
2135 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2136 {
2137 return 0;
2138 }
2139 EXPORT_SYMBOL(sock_no_poll);
2140
2141 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2142 {
2143 return -EOPNOTSUPP;
2144 }
2145 EXPORT_SYMBOL(sock_no_ioctl);
2146
2147 int sock_no_listen(struct socket *sock, int backlog)
2148 {
2149 return -EOPNOTSUPP;
2150 }
2151 EXPORT_SYMBOL(sock_no_listen);
2152
2153 int sock_no_shutdown(struct socket *sock, int how)
2154 {
2155 return -EOPNOTSUPP;
2156 }
2157 EXPORT_SYMBOL(sock_no_shutdown);
2158
2159 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2160 char __user *optval, unsigned int optlen)
2161 {
2162 return -EOPNOTSUPP;
2163 }
2164 EXPORT_SYMBOL(sock_no_setsockopt);
2165
2166 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2167 char __user *optval, int __user *optlen)
2168 {
2169 return -EOPNOTSUPP;
2170 }
2171 EXPORT_SYMBOL(sock_no_getsockopt);
2172
2173 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2174 {
2175 return -EOPNOTSUPP;
2176 }
2177 EXPORT_SYMBOL(sock_no_sendmsg);
2178
2179 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2180 int flags)
2181 {
2182 return -EOPNOTSUPP;
2183 }
2184 EXPORT_SYMBOL(sock_no_recvmsg);
2185
2186 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2187 {
2188 /* Mirror missing mmap method error code */
2189 return -ENODEV;
2190 }
2191 EXPORT_SYMBOL(sock_no_mmap);
2192
2193 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2194 {
2195 ssize_t res;
2196 struct msghdr msg = {.msg_flags = flags};
2197 struct kvec iov;
2198 char *kaddr = kmap(page);
2199 iov.iov_base = kaddr + offset;
2200 iov.iov_len = size;
2201 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2202 kunmap(page);
2203 return res;
2204 }
2205 EXPORT_SYMBOL(sock_no_sendpage);
2206
2207 /*
2208 * Default Socket Callbacks
2209 */
2210
2211 static void sock_def_wakeup(struct sock *sk)
2212 {
2213 struct socket_wq *wq;
2214
2215 rcu_read_lock();
2216 wq = rcu_dereference(sk->sk_wq);
2217 if (wq_has_sleeper(wq))
2218 wake_up_interruptible_all(&wq->wait);
2219 rcu_read_unlock();
2220 }
2221
2222 static void sock_def_error_report(struct sock *sk)
2223 {
2224 struct socket_wq *wq;
2225
2226 rcu_read_lock();
2227 wq = rcu_dereference(sk->sk_wq);
2228 if (wq_has_sleeper(wq))
2229 wake_up_interruptible_poll(&wq->wait, POLLERR);
2230 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2231 rcu_read_unlock();
2232 }
2233
2234 static void sock_def_readable(struct sock *sk)
2235 {
2236 struct socket_wq *wq;
2237
2238 rcu_read_lock();
2239 wq = rcu_dereference(sk->sk_wq);
2240 if (wq_has_sleeper(wq))
2241 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2242 POLLRDNORM | POLLRDBAND);
2243 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2244 rcu_read_unlock();
2245 }
2246
2247 static void sock_def_write_space(struct sock *sk)
2248 {
2249 struct socket_wq *wq;
2250
2251 rcu_read_lock();
2252
2253 /* Do not wake up a writer until he can make "significant"
2254 * progress. --DaveM
2255 */
2256 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2257 wq = rcu_dereference(sk->sk_wq);
2258 if (wq_has_sleeper(wq))
2259 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2260 POLLWRNORM | POLLWRBAND);
2261
2262 /* Should agree with poll, otherwise some programs break */
2263 if (sock_writeable(sk))
2264 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2265 }
2266
2267 rcu_read_unlock();
2268 }
2269
2270 static void sock_def_destruct(struct sock *sk)
2271 {
2272 }
2273
2274 void sk_send_sigurg(struct sock *sk)
2275 {
2276 if (sk->sk_socket && sk->sk_socket->file)
2277 if (send_sigurg(&sk->sk_socket->file->f_owner))
2278 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2279 }
2280 EXPORT_SYMBOL(sk_send_sigurg);
2281
2282 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2283 unsigned long expires)
2284 {
2285 if (!mod_timer(timer, expires))
2286 sock_hold(sk);
2287 }
2288 EXPORT_SYMBOL(sk_reset_timer);
2289
2290 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2291 {
2292 if (del_timer(timer))
2293 __sock_put(sk);
2294 }
2295 EXPORT_SYMBOL(sk_stop_timer);
2296
2297 void sock_init_data(struct socket *sock, struct sock *sk)
2298 {
2299 skb_queue_head_init(&sk->sk_receive_queue);
2300 skb_queue_head_init(&sk->sk_write_queue);
2301 skb_queue_head_init(&sk->sk_error_queue);
2302
2303 sk->sk_send_head = NULL;
2304
2305 init_timer(&sk->sk_timer);
2306
2307 sk->sk_allocation = GFP_KERNEL;
2308 sk->sk_rcvbuf = sysctl_rmem_default;
2309 sk->sk_sndbuf = sysctl_wmem_default;
2310 sk->sk_state = TCP_CLOSE;
2311 sk_set_socket(sk, sock);
2312
2313 sock_set_flag(sk, SOCK_ZAPPED);
2314
2315 if (sock) {
2316 sk->sk_type = sock->type;
2317 sk->sk_wq = sock->wq;
2318 sock->sk = sk;
2319 } else
2320 sk->sk_wq = NULL;
2321
2322 spin_lock_init(&sk->sk_dst_lock);
2323 rwlock_init(&sk->sk_callback_lock);
2324 lockdep_set_class_and_name(&sk->sk_callback_lock,
2325 af_callback_keys + sk->sk_family,
2326 af_family_clock_key_strings[sk->sk_family]);
2327
2328 sk->sk_state_change = sock_def_wakeup;
2329 sk->sk_data_ready = sock_def_readable;
2330 sk->sk_write_space = sock_def_write_space;
2331 sk->sk_error_report = sock_def_error_report;
2332 sk->sk_destruct = sock_def_destruct;
2333
2334 sk->sk_frag.page = NULL;
2335 sk->sk_frag.offset = 0;
2336 sk->sk_peek_off = -1;
2337
2338 sk->sk_peer_pid = NULL;
2339 sk->sk_peer_cred = NULL;
2340 sk->sk_write_pending = 0;
2341 sk->sk_rcvlowat = 1;
2342 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2343 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2344
2345 sk->sk_stamp = ktime_set(-1L, 0);
2346
2347 #ifdef CONFIG_NET_RX_BUSY_POLL
2348 sk->sk_napi_id = 0;
2349 sk->sk_ll_usec = sysctl_net_busy_read;
2350 #endif
2351
2352 sk->sk_max_pacing_rate = ~0U;
2353 sk->sk_pacing_rate = ~0U;
2354 /*
2355 * Before updating sk_refcnt, we must commit prior changes to memory
2356 * (Documentation/RCU/rculist_nulls.txt for details)
2357 */
2358 smp_wmb();
2359 atomic_set(&sk->sk_refcnt, 1);
2360 atomic_set(&sk->sk_drops, 0);
2361 }
2362 EXPORT_SYMBOL(sock_init_data);
2363
2364 void lock_sock_nested(struct sock *sk, int subclass)
2365 {
2366 might_sleep();
2367 spin_lock_bh(&sk->sk_lock.slock);
2368 if (sk->sk_lock.owned)
2369 __lock_sock(sk);
2370 sk->sk_lock.owned = 1;
2371 spin_unlock(&sk->sk_lock.slock);
2372 /*
2373 * The sk_lock has mutex_lock() semantics here:
2374 */
2375 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2376 local_bh_enable();
2377 }
2378 EXPORT_SYMBOL(lock_sock_nested);
2379
2380 void release_sock(struct sock *sk)
2381 {
2382 /*
2383 * The sk_lock has mutex_unlock() semantics:
2384 */
2385 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2386
2387 spin_lock_bh(&sk->sk_lock.slock);
2388 if (sk->sk_backlog.tail)
2389 __release_sock(sk);
2390
2391 /* Warning : release_cb() might need to release sk ownership,
2392 * ie call sock_release_ownership(sk) before us.
2393 */
2394 if (sk->sk_prot->release_cb)
2395 sk->sk_prot->release_cb(sk);
2396
2397 sock_release_ownership(sk);
2398 if (waitqueue_active(&sk->sk_lock.wq))
2399 wake_up(&sk->sk_lock.wq);
2400 spin_unlock_bh(&sk->sk_lock.slock);
2401 }
2402 EXPORT_SYMBOL(release_sock);
2403
2404 /**
2405 * lock_sock_fast - fast version of lock_sock
2406 * @sk: socket
2407 *
2408 * This version should be used for very small section, where process wont block
2409 * return false if fast path is taken
2410 * sk_lock.slock locked, owned = 0, BH disabled
2411 * return true if slow path is taken
2412 * sk_lock.slock unlocked, owned = 1, BH enabled
2413 */
2414 bool lock_sock_fast(struct sock *sk)
2415 {
2416 might_sleep();
2417 spin_lock_bh(&sk->sk_lock.slock);
2418
2419 if (!sk->sk_lock.owned)
2420 /*
2421 * Note : We must disable BH
2422 */
2423 return false;
2424
2425 __lock_sock(sk);
2426 sk->sk_lock.owned = 1;
2427 spin_unlock(&sk->sk_lock.slock);
2428 /*
2429 * The sk_lock has mutex_lock() semantics here:
2430 */
2431 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2432 local_bh_enable();
2433 return true;
2434 }
2435 EXPORT_SYMBOL(lock_sock_fast);
2436
2437 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2438 {
2439 struct timeval tv;
2440 if (!sock_flag(sk, SOCK_TIMESTAMP))
2441 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2442 tv = ktime_to_timeval(sk->sk_stamp);
2443 if (tv.tv_sec == -1)
2444 return -ENOENT;
2445 if (tv.tv_sec == 0) {
2446 sk->sk_stamp = ktime_get_real();
2447 tv = ktime_to_timeval(sk->sk_stamp);
2448 }
2449 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2450 }
2451 EXPORT_SYMBOL(sock_get_timestamp);
2452
2453 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2454 {
2455 struct timespec ts;
2456 if (!sock_flag(sk, SOCK_TIMESTAMP))
2457 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2458 ts = ktime_to_timespec(sk->sk_stamp);
2459 if (ts.tv_sec == -1)
2460 return -ENOENT;
2461 if (ts.tv_sec == 0) {
2462 sk->sk_stamp = ktime_get_real();
2463 ts = ktime_to_timespec(sk->sk_stamp);
2464 }
2465 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2466 }
2467 EXPORT_SYMBOL(sock_get_timestampns);
2468
2469 void sock_enable_timestamp(struct sock *sk, int flag)
2470 {
2471 if (!sock_flag(sk, flag)) {
2472 unsigned long previous_flags = sk->sk_flags;
2473
2474 sock_set_flag(sk, flag);
2475 /*
2476 * we just set one of the two flags which require net
2477 * time stamping, but time stamping might have been on
2478 * already because of the other one
2479 */
2480 if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2481 net_enable_timestamp();
2482 }
2483 }
2484
2485 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2486 int level, int type)
2487 {
2488 struct sock_exterr_skb *serr;
2489 struct sk_buff *skb;
2490 int copied, err;
2491
2492 err = -EAGAIN;
2493 skb = sock_dequeue_err_skb(sk);
2494 if (skb == NULL)
2495 goto out;
2496
2497 copied = skb->len;
2498 if (copied > len) {
2499 msg->msg_flags |= MSG_TRUNC;
2500 copied = len;
2501 }
2502 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2503 if (err)
2504 goto out_free_skb;
2505
2506 sock_recv_timestamp(msg, sk, skb);
2507
2508 serr = SKB_EXT_ERR(skb);
2509 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2510
2511 msg->msg_flags |= MSG_ERRQUEUE;
2512 err = copied;
2513
2514 out_free_skb:
2515 kfree_skb(skb);
2516 out:
2517 return err;
2518 }
2519 EXPORT_SYMBOL(sock_recv_errqueue);
2520
2521 /*
2522 * Get a socket option on an socket.
2523 *
2524 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2525 * asynchronous errors should be reported by getsockopt. We assume
2526 * this means if you specify SO_ERROR (otherwise whats the point of it).
2527 */
2528 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2529 char __user *optval, int __user *optlen)
2530 {
2531 struct sock *sk = sock->sk;
2532
2533 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2534 }
2535 EXPORT_SYMBOL(sock_common_getsockopt);
2536
2537 #ifdef CONFIG_COMPAT
2538 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2539 char __user *optval, int __user *optlen)
2540 {
2541 struct sock *sk = sock->sk;
2542
2543 if (sk->sk_prot->compat_getsockopt != NULL)
2544 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2545 optval, optlen);
2546 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2547 }
2548 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2549 #endif
2550
2551 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2552 int flags)
2553 {
2554 struct sock *sk = sock->sk;
2555 int addr_len = 0;
2556 int err;
2557
2558 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2559 flags & ~MSG_DONTWAIT, &addr_len);
2560 if (err >= 0)
2561 msg->msg_namelen = addr_len;
2562 return err;
2563 }
2564 EXPORT_SYMBOL(sock_common_recvmsg);
2565
2566 /*
2567 * Set socket options on an inet socket.
2568 */
2569 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2570 char __user *optval, unsigned int optlen)
2571 {
2572 struct sock *sk = sock->sk;
2573
2574 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2575 }
2576 EXPORT_SYMBOL(sock_common_setsockopt);
2577
2578 #ifdef CONFIG_COMPAT
2579 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2580 char __user *optval, unsigned int optlen)
2581 {
2582 struct sock *sk = sock->sk;
2583
2584 if (sk->sk_prot->compat_setsockopt != NULL)
2585 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2586 optval, optlen);
2587 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2588 }
2589 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2590 #endif
2591
2592 void sk_common_release(struct sock *sk)
2593 {
2594 if (sk->sk_prot->destroy)
2595 sk->sk_prot->destroy(sk);
2596
2597 /*
2598 * Observation: when sock_common_release is called, processes have
2599 * no access to socket. But net still has.
2600 * Step one, detach it from networking:
2601 *
2602 * A. Remove from hash tables.
2603 */
2604
2605 sk->sk_prot->unhash(sk);
2606
2607 /*
2608 * In this point socket cannot receive new packets, but it is possible
2609 * that some packets are in flight because some CPU runs receiver and
2610 * did hash table lookup before we unhashed socket. They will achieve
2611 * receive queue and will be purged by socket destructor.
2612 *
2613 * Also we still have packets pending on receive queue and probably,
2614 * our own packets waiting in device queues. sock_destroy will drain
2615 * receive queue, but transmitted packets will delay socket destruction
2616 * until the last reference will be released.
2617 */
2618
2619 sock_orphan(sk);
2620
2621 xfrm_sk_free_policy(sk);
2622
2623 sk_refcnt_debug_release(sk);
2624
2625 if (sk->sk_frag.page) {
2626 put_page(sk->sk_frag.page);
2627 sk->sk_frag.page = NULL;
2628 }
2629
2630 sock_put(sk);
2631 }
2632 EXPORT_SYMBOL(sk_common_release);
2633
2634 #ifdef CONFIG_PROC_FS
2635 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2636 struct prot_inuse {
2637 int val[PROTO_INUSE_NR];
2638 };
2639
2640 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2641
2642 #ifdef CONFIG_NET_NS
2643 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2644 {
2645 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2646 }
2647 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2648
2649 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2650 {
2651 int cpu, idx = prot->inuse_idx;
2652 int res = 0;
2653
2654 for_each_possible_cpu(cpu)
2655 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2656
2657 return res >= 0 ? res : 0;
2658 }
2659 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2660
2661 static int __net_init sock_inuse_init_net(struct net *net)
2662 {
2663 net->core.inuse = alloc_percpu(struct prot_inuse);
2664 return net->core.inuse ? 0 : -ENOMEM;
2665 }
2666
2667 static void __net_exit sock_inuse_exit_net(struct net *net)
2668 {
2669 free_percpu(net->core.inuse);
2670 }
2671
2672 static struct pernet_operations net_inuse_ops = {
2673 .init = sock_inuse_init_net,
2674 .exit = sock_inuse_exit_net,
2675 };
2676
2677 static __init int net_inuse_init(void)
2678 {
2679 if (register_pernet_subsys(&net_inuse_ops))
2680 panic("Cannot initialize net inuse counters");
2681
2682 return 0;
2683 }
2684
2685 core_initcall(net_inuse_init);
2686 #else
2687 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2688
2689 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2690 {
2691 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2692 }
2693 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2694
2695 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2696 {
2697 int cpu, idx = prot->inuse_idx;
2698 int res = 0;
2699
2700 for_each_possible_cpu(cpu)
2701 res += per_cpu(prot_inuse, cpu).val[idx];
2702
2703 return res >= 0 ? res : 0;
2704 }
2705 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2706 #endif
2707
2708 static void assign_proto_idx(struct proto *prot)
2709 {
2710 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2711
2712 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2713 pr_err("PROTO_INUSE_NR exhausted\n");
2714 return;
2715 }
2716
2717 set_bit(prot->inuse_idx, proto_inuse_idx);
2718 }
2719
2720 static void release_proto_idx(struct proto *prot)
2721 {
2722 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2723 clear_bit(prot->inuse_idx, proto_inuse_idx);
2724 }
2725 #else
2726 static inline void assign_proto_idx(struct proto *prot)
2727 {
2728 }
2729
2730 static inline void release_proto_idx(struct proto *prot)
2731 {
2732 }
2733 #endif
2734
2735 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2736 {
2737 if (!rsk_prot)
2738 return;
2739 kfree(rsk_prot->slab_name);
2740 rsk_prot->slab_name = NULL;
2741 if (rsk_prot->slab) {
2742 kmem_cache_destroy(rsk_prot->slab);
2743 rsk_prot->slab = NULL;
2744 }
2745 }
2746
2747 static int req_prot_init(const struct proto *prot)
2748 {
2749 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2750
2751 if (!rsk_prot)
2752 return 0;
2753
2754 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2755 prot->name);
2756 if (!rsk_prot->slab_name)
2757 return -ENOMEM;
2758
2759 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2760 rsk_prot->obj_size, 0,
2761 0, NULL);
2762
2763 if (!rsk_prot->slab) {
2764 pr_crit("%s: Can't create request sock SLAB cache!\n",
2765 prot->name);
2766 return -ENOMEM;
2767 }
2768 return 0;
2769 }
2770
2771 int proto_register(struct proto *prot, int alloc_slab)
2772 {
2773 if (alloc_slab) {
2774 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2775 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2776 NULL);
2777
2778 if (prot->slab == NULL) {
2779 pr_crit("%s: Can't create sock SLAB cache!\n",
2780 prot->name);
2781 goto out;
2782 }
2783
2784 if (req_prot_init(prot))
2785 goto out_free_request_sock_slab;
2786
2787 if (prot->twsk_prot != NULL) {
2788 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2789
2790 if (prot->twsk_prot->twsk_slab_name == NULL)
2791 goto out_free_request_sock_slab;
2792
2793 prot->twsk_prot->twsk_slab =
2794 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2795 prot->twsk_prot->twsk_obj_size,
2796 0,
2797 prot->slab_flags,
2798 NULL);
2799 if (prot->twsk_prot->twsk_slab == NULL)
2800 goto out_free_timewait_sock_slab_name;
2801 }
2802 }
2803
2804 mutex_lock(&proto_list_mutex);
2805 list_add(&prot->node, &proto_list);
2806 assign_proto_idx(prot);
2807 mutex_unlock(&proto_list_mutex);
2808 return 0;
2809
2810 out_free_timewait_sock_slab_name:
2811 kfree(prot->twsk_prot->twsk_slab_name);
2812 out_free_request_sock_slab:
2813 req_prot_cleanup(prot->rsk_prot);
2814
2815 kmem_cache_destroy(prot->slab);
2816 prot->slab = NULL;
2817 out:
2818 return -ENOBUFS;
2819 }
2820 EXPORT_SYMBOL(proto_register);
2821
2822 void proto_unregister(struct proto *prot)
2823 {
2824 mutex_lock(&proto_list_mutex);
2825 release_proto_idx(prot);
2826 list_del(&prot->node);
2827 mutex_unlock(&proto_list_mutex);
2828
2829 if (prot->slab != NULL) {
2830 kmem_cache_destroy(prot->slab);
2831 prot->slab = NULL;
2832 }
2833
2834 req_prot_cleanup(prot->rsk_prot);
2835
2836 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2837 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2838 kfree(prot->twsk_prot->twsk_slab_name);
2839 prot->twsk_prot->twsk_slab = NULL;
2840 }
2841 }
2842 EXPORT_SYMBOL(proto_unregister);
2843
2844 #ifdef CONFIG_PROC_FS
2845 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2846 __acquires(proto_list_mutex)
2847 {
2848 mutex_lock(&proto_list_mutex);
2849 return seq_list_start_head(&proto_list, *pos);
2850 }
2851
2852 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2853 {
2854 return seq_list_next(v, &proto_list, pos);
2855 }
2856
2857 static void proto_seq_stop(struct seq_file *seq, void *v)
2858 __releases(proto_list_mutex)
2859 {
2860 mutex_unlock(&proto_list_mutex);
2861 }
2862
2863 static char proto_method_implemented(const void *method)
2864 {
2865 return method == NULL ? 'n' : 'y';
2866 }
2867 static long sock_prot_memory_allocated(struct proto *proto)
2868 {
2869 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2870 }
2871
2872 static char *sock_prot_memory_pressure(struct proto *proto)
2873 {
2874 return proto->memory_pressure != NULL ?
2875 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2876 }
2877
2878 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2879 {
2880
2881 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2882 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2883 proto->name,
2884 proto->obj_size,
2885 sock_prot_inuse_get(seq_file_net(seq), proto),
2886 sock_prot_memory_allocated(proto),
2887 sock_prot_memory_pressure(proto),
2888 proto->max_header,
2889 proto->slab == NULL ? "no" : "yes",
2890 module_name(proto->owner),
2891 proto_method_implemented(proto->close),
2892 proto_method_implemented(proto->connect),
2893 proto_method_implemented(proto->disconnect),
2894 proto_method_implemented(proto->accept),
2895 proto_method_implemented(proto->ioctl),
2896 proto_method_implemented(proto->init),
2897 proto_method_implemented(proto->destroy),
2898 proto_method_implemented(proto->shutdown),
2899 proto_method_implemented(proto->setsockopt),
2900 proto_method_implemented(proto->getsockopt),
2901 proto_method_implemented(proto->sendmsg),
2902 proto_method_implemented(proto->recvmsg),
2903 proto_method_implemented(proto->sendpage),
2904 proto_method_implemented(proto->bind),
2905 proto_method_implemented(proto->backlog_rcv),
2906 proto_method_implemented(proto->hash),
2907 proto_method_implemented(proto->unhash),
2908 proto_method_implemented(proto->get_port),
2909 proto_method_implemented(proto->enter_memory_pressure));
2910 }
2911
2912 static int proto_seq_show(struct seq_file *seq, void *v)
2913 {
2914 if (v == &proto_list)
2915 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2916 "protocol",
2917 "size",
2918 "sockets",
2919 "memory",
2920 "press",
2921 "maxhdr",
2922 "slab",
2923 "module",
2924 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2925 else
2926 proto_seq_printf(seq, list_entry(v, struct proto, node));
2927 return 0;
2928 }
2929
2930 static const struct seq_operations proto_seq_ops = {
2931 .start = proto_seq_start,
2932 .next = proto_seq_next,
2933 .stop = proto_seq_stop,
2934 .show = proto_seq_show,
2935 };
2936
2937 static int proto_seq_open(struct inode *inode, struct file *file)
2938 {
2939 return seq_open_net(inode, file, &proto_seq_ops,
2940 sizeof(struct seq_net_private));
2941 }
2942
2943 static const struct file_operations proto_seq_fops = {
2944 .owner = THIS_MODULE,
2945 .open = proto_seq_open,
2946 .read = seq_read,
2947 .llseek = seq_lseek,
2948 .release = seq_release_net,
2949 };
2950
2951 static __net_init int proto_init_net(struct net *net)
2952 {
2953 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
2954 return -ENOMEM;
2955
2956 return 0;
2957 }
2958
2959 static __net_exit void proto_exit_net(struct net *net)
2960 {
2961 remove_proc_entry("protocols", net->proc_net);
2962 }
2963
2964
2965 static __net_initdata struct pernet_operations proto_net_ops = {
2966 .init = proto_init_net,
2967 .exit = proto_exit_net,
2968 };
2969
2970 static int __init proto_init(void)
2971 {
2972 return register_pernet_subsys(&proto_net_ops);
2973 }
2974
2975 subsys_initcall(proto_init);
2976
2977 #endif /* PROC_FS */
Linux kernel - Deliverables
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