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Linux 4.1.16
[linux/fpc-iii.git] / net / core / sock.c
blob47fc8bb3b9462a6b599261b81f4bd0ef4404eba0
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
135 #include <linux/filter.h>
136
137 #include <trace/events/sock.h>
138
139 #ifdef CONFIG_INET
140 #include <net/tcp.h>
141 #endif
142
143 #include <net/busy_poll.h>
144
145 static DEFINE_MUTEX(proto_list_mutex);
146 static LIST_HEAD(proto_list);
147
148 /**
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
153 *
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.
157 */
158 bool sk_ns_capable(const struct sock *sk,
159 struct user_namespace *user_ns, int cap)
160 {
161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
162 ns_capable(user_ns, cap);
163 }
164 EXPORT_SYMBOL(sk_ns_capable);
165
166 /**
167 * sk_capable - Socket global capability test
168 * @sk: Socket to use a capability on or through
169 * @cap: The global capability to use
170 *
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.
174 */
175 bool sk_capable(const struct sock *sk, int cap)
176 {
177 return sk_ns_capable(sk, &init_user_ns, cap);
178 }
179 EXPORT_SYMBOL(sk_capable);
180
181 /**
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
185 *
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.
189 */
190 bool sk_net_capable(const struct sock *sk, int cap)
191 {
192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
193 }
194 EXPORT_SYMBOL(sk_net_capable);
195
196
197 #ifdef CONFIG_MEMCG_KMEM
198 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
199 {
200 struct proto *proto;
201 int ret = 0;
202
203 mutex_lock(&proto_list_mutex);
204 list_for_each_entry(proto, &proto_list, node) {
205 if (proto->init_cgroup) {
206 ret = proto->init_cgroup(memcg, ss);
207 if (ret)
208 goto out;
209 }
210 }
211
212 mutex_unlock(&proto_list_mutex);
213 return ret;
214 out:
215 list_for_each_entry_continue_reverse(proto, &proto_list, node)
216 if (proto->destroy_cgroup)
217 proto->destroy_cgroup(memcg);
218 mutex_unlock(&proto_list_mutex);
219 return ret;
220 }
221
222 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
223 {
224 struct proto *proto;
225
226 mutex_lock(&proto_list_mutex);
227 list_for_each_entry_reverse(proto, &proto_list, node)
228 if (proto->destroy_cgroup)
229 proto->destroy_cgroup(memcg);
230 mutex_unlock(&proto_list_mutex);
231 }
232 #endif
233
234 /*
235 * Each address family might have different locking rules, so we have
236 * one slock key per address family:
237 */
238 static struct lock_class_key af_family_keys[AF_MAX];
239 static struct lock_class_key af_family_slock_keys[AF_MAX];
240
241 #if defined(CONFIG_MEMCG_KMEM)
242 struct static_key memcg_socket_limit_enabled;
243 EXPORT_SYMBOL(memcg_socket_limit_enabled);
244 #endif
245
246 /*
247 * Make lock validator output more readable. (we pre-construct these
248 * strings build-time, so that runtime initialization of socket
249 * locks is fast):
250 */
251 static const char *const af_family_key_strings[AF_MAX+1] = {
252 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
253 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
254 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
255 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
256 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
257 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
258 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
259 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
260 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
261 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
262 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
263 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
264 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
265 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
266 };
267 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
268 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
269 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
270 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
271 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
272 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
273 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
274 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
275 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
276 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
277 "slock-27" , "slock-28" , "slock-AF_CAN" ,
278 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
279 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
280 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
281 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
282 };
283 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
284 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
285 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
286 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
287 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
288 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
289 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
290 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
291 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
292 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
293 "clock-27" , "clock-28" , "clock-AF_CAN" ,
294 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
295 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
296 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
297 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
298 };
299
300 /*
301 * sk_callback_lock locking rules are per-address-family,
302 * so split the lock classes by using a per-AF key:
303 */
304 static struct lock_class_key af_callback_keys[AF_MAX];
305
306 /* Take into consideration the size of the struct sk_buff overhead in the
307 * determination of these values, since that is non-constant across
308 * platforms. This makes socket queueing behavior and performance
309 * not depend upon such differences.
310 */
311 #define _SK_MEM_PACKETS 256
312 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
313 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
314 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
315
316 /* Run time adjustable parameters. */
317 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
318 EXPORT_SYMBOL(sysctl_wmem_max);
319 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
320 EXPORT_SYMBOL(sysctl_rmem_max);
321 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
322 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
323
324 /* Maximal space eaten by iovec or ancillary data plus some space */
325 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
326 EXPORT_SYMBOL(sysctl_optmem_max);
327
328 int sysctl_tstamp_allow_data __read_mostly = 1;
329
330 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
331 EXPORT_SYMBOL_GPL(memalloc_socks);
332
333 /**
334 * sk_set_memalloc - sets %SOCK_MEMALLOC
335 * @sk: socket to set it on
336 *
337 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
338 * It's the responsibility of the admin to adjust min_free_kbytes
339 * to meet the requirements
340 */
341 void sk_set_memalloc(struct sock *sk)
342 {
343 sock_set_flag(sk, SOCK_MEMALLOC);
344 sk->sk_allocation |= __GFP_MEMALLOC;
345 static_key_slow_inc(&memalloc_socks);
346 }
347 EXPORT_SYMBOL_GPL(sk_set_memalloc);
348
349 void sk_clear_memalloc(struct sock *sk)
350 {
351 sock_reset_flag(sk, SOCK_MEMALLOC);
352 sk->sk_allocation &= ~__GFP_MEMALLOC;
353 static_key_slow_dec(&memalloc_socks);
354
355 /*
356 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
357 * progress of swapping. SOCK_MEMALLOC may be cleared while
358 * it has rmem allocations due to the last swapfile being deactivated
359 * but there is a risk that the socket is unusable due to exceeding
360 * the rmem limits. Reclaim the reserves and obey rmem limits again.
361 */
362 sk_mem_reclaim(sk);
363 }
364 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
365
366 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
367 {
368 int ret;
369 unsigned long pflags = current->flags;
370
371 /* these should have been dropped before queueing */
372 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
373
374 current->flags |= PF_MEMALLOC;
375 ret = sk->sk_backlog_rcv(sk, skb);
376 tsk_restore_flags(current, pflags, PF_MEMALLOC);
377
378 return ret;
379 }
380 EXPORT_SYMBOL(__sk_backlog_rcv);
381
382 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
383 {
384 struct timeval tv;
385
386 if (optlen < sizeof(tv))
387 return -EINVAL;
388 if (copy_from_user(&tv, optval, sizeof(tv)))
389 return -EFAULT;
390 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
391 return -EDOM;
392
393 if (tv.tv_sec < 0) {
394 static int warned __read_mostly;
395
396 *timeo_p = 0;
397 if (warned < 10 && net_ratelimit()) {
398 warned++;
399 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
400 __func__, current->comm, task_pid_nr(current));
401 }
402 return 0;
403 }
404 *timeo_p = MAX_SCHEDULE_TIMEOUT;
405 if (tv.tv_sec == 0 && tv.tv_usec == 0)
406 return 0;
407 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
408 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
409 return 0;
410 }
411
412 static void sock_warn_obsolete_bsdism(const char *name)
413 {
414 static int warned;
415 static char warncomm[TASK_COMM_LEN];
416 if (strcmp(warncomm, current->comm) && warned < 5) {
417 strcpy(warncomm, current->comm);
418 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
419 warncomm, name);
420 warned++;
421 }
422 }
423
424 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
425 {
426 if (sk->sk_flags & flags) {
427 sk->sk_flags &= ~flags;
428 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
429 net_disable_timestamp();
430 }
431 }
432
433
434 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
435 {
436 int err;
437 unsigned long flags;
438 struct sk_buff_head *list = &sk->sk_receive_queue;
439
440 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
441 atomic_inc(&sk->sk_drops);
442 trace_sock_rcvqueue_full(sk, skb);
443 return -ENOMEM;
444 }
445
446 err = sk_filter(sk, skb);
447 if (err)
448 return err;
449
450 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
451 atomic_inc(&sk->sk_drops);
452 return -ENOBUFS;
453 }
454
455 skb->dev = NULL;
456 skb_set_owner_r(skb, sk);
457
458 /* we escape from rcu protected region, make sure we dont leak
459 * a norefcounted dst
460 */
461 skb_dst_force(skb);
462
463 spin_lock_irqsave(&list->lock, flags);
464 sock_skb_set_dropcount(sk, skb);
465 __skb_queue_tail(list, skb);
466 spin_unlock_irqrestore(&list->lock, flags);
467
468 if (!sock_flag(sk, SOCK_DEAD))
469 sk->sk_data_ready(sk);
470 return 0;
471 }
472 EXPORT_SYMBOL(sock_queue_rcv_skb);
473
474 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
475 {
476 int rc = NET_RX_SUCCESS;
477
478 if (sk_filter(sk, skb))
479 goto discard_and_relse;
480
481 skb->dev = NULL;
482
483 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
484 atomic_inc(&sk->sk_drops);
485 goto discard_and_relse;
486 }
487 if (nested)
488 bh_lock_sock_nested(sk);
489 else
490 bh_lock_sock(sk);
491 if (!sock_owned_by_user(sk)) {
492 /*
493 * trylock + unlock semantics:
494 */
495 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
496
497 rc = sk_backlog_rcv(sk, skb);
498
499 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
500 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
501 bh_unlock_sock(sk);
502 atomic_inc(&sk->sk_drops);
503 goto discard_and_relse;
504 }
505
506 bh_unlock_sock(sk);
507 out:
508 sock_put(sk);
509 return rc;
510 discard_and_relse:
511 kfree_skb(skb);
512 goto out;
513 }
514 EXPORT_SYMBOL(sk_receive_skb);
515
516 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
517 {
518 struct dst_entry *dst = __sk_dst_get(sk);
519
520 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
521 sk_tx_queue_clear(sk);
522 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
523 dst_release(dst);
524 return NULL;
525 }
526
527 return dst;
528 }
529 EXPORT_SYMBOL(__sk_dst_check);
530
531 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
532 {
533 struct dst_entry *dst = sk_dst_get(sk);
534
535 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
536 sk_dst_reset(sk);
537 dst_release(dst);
538 return NULL;
539 }
540
541 return dst;
542 }
543 EXPORT_SYMBOL(sk_dst_check);
544
545 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
546 int optlen)
547 {
548 int ret = -ENOPROTOOPT;
549 #ifdef CONFIG_NETDEVICES
550 struct net *net = sock_net(sk);
551 char devname[IFNAMSIZ];
552 int index;
553
554 /* Sorry... */
555 ret = -EPERM;
556 if (!ns_capable(net->user_ns, CAP_NET_RAW))
557 goto out;
558
559 ret = -EINVAL;
560 if (optlen < 0)
561 goto out;
562
563 /* Bind this socket to a particular device like "eth0",
564 * as specified in the passed interface name. If the
565 * name is "" or the option length is zero the socket
566 * is not bound.
567 */
568 if (optlen > IFNAMSIZ - 1)
569 optlen = IFNAMSIZ - 1;
570 memset(devname, 0, sizeof(devname));
571
572 ret = -EFAULT;
573 if (copy_from_user(devname, optval, optlen))
574 goto out;
575
576 index = 0;
577 if (devname[0] != '\0') {
578 struct net_device *dev;
579
580 rcu_read_lock();
581 dev = dev_get_by_name_rcu(net, devname);
582 if (dev)
583 index = dev->ifindex;
584 rcu_read_unlock();
585 ret = -ENODEV;
586 if (!dev)
587 goto out;
588 }
589
590 lock_sock(sk);
591 sk->sk_bound_dev_if = index;
592 sk_dst_reset(sk);
593 release_sock(sk);
594
595 ret = 0;
596
597 out:
598 #endif
599
600 return ret;
601 }
602
603 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
604 int __user *optlen, int len)
605 {
606 int ret = -ENOPROTOOPT;
607 #ifdef CONFIG_NETDEVICES
608 struct net *net = sock_net(sk);
609 char devname[IFNAMSIZ];
610
611 if (sk->sk_bound_dev_if == 0) {
612 len = 0;
613 goto zero;
614 }
615
616 ret = -EINVAL;
617 if (len < IFNAMSIZ)
618 goto out;
619
620 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
621 if (ret)
622 goto out;
623
624 len = strlen(devname) + 1;
625
626 ret = -EFAULT;
627 if (copy_to_user(optval, devname, len))
628 goto out;
629
630 zero:
631 ret = -EFAULT;
632 if (put_user(len, optlen))
633 goto out;
634
635 ret = 0;
636
637 out:
638 #endif
639
640 return ret;
641 }
642
643 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
644 {
645 if (valbool)
646 sock_set_flag(sk, bit);
647 else
648 sock_reset_flag(sk, bit);
649 }
650
651 bool sk_mc_loop(struct sock *sk)
652 {
653 if (dev_recursion_level())
654 return false;
655 if (!sk)
656 return true;
657 switch (sk->sk_family) {
658 case AF_INET:
659 return inet_sk(sk)->mc_loop;
660 #if IS_ENABLED(CONFIG_IPV6)
661 case AF_INET6:
662 return inet6_sk(sk)->mc_loop;
663 #endif
664 }
665 WARN_ON(1);
666 return true;
667 }
668 EXPORT_SYMBOL(sk_mc_loop);
669
670 /*
671 * This is meant for all protocols to use and covers goings on
672 * at the socket level. Everything here is generic.
673 */
674
675 int sock_setsockopt(struct socket *sock, int level, int optname,
676 char __user *optval, unsigned int optlen)
677 {
678 struct sock *sk = sock->sk;
679 int val;
680 int valbool;
681 struct linger ling;
682 int ret = 0;
683
684 /*
685 * Options without arguments
686 */
687
688 if (optname == SO_BINDTODEVICE)
689 return sock_setbindtodevice(sk, optval, optlen);
690
691 if (optlen < sizeof(int))
692 return -EINVAL;
693
694 if (get_user(val, (int __user *)optval))
695 return -EFAULT;
696
697 valbool = val ? 1 : 0;
698
699 lock_sock(sk);
700
701 switch (optname) {
702 case SO_DEBUG:
703 if (val && !capable(CAP_NET_ADMIN))
704 ret = -EACCES;
705 else
706 sock_valbool_flag(sk, SOCK_DBG, valbool);
707 break;
708 case SO_REUSEADDR:
709 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
710 break;
711 case SO_REUSEPORT:
712 sk->sk_reuseport = valbool;
713 break;
714 case SO_TYPE:
715 case SO_PROTOCOL:
716 case SO_DOMAIN:
717 case SO_ERROR:
718 ret = -ENOPROTOOPT;
719 break;
720 case SO_DONTROUTE:
721 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
722 break;
723 case SO_BROADCAST:
724 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
725 break;
726 case SO_SNDBUF:
727 /* Don't error on this BSD doesn't and if you think
728 * about it this is right. Otherwise apps have to
729 * play 'guess the biggest size' games. RCVBUF/SNDBUF
730 * are treated in BSD as hints
731 */
732 val = min_t(u32, val, sysctl_wmem_max);
733 set_sndbuf:
734 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
735 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
736 /* Wake up sending tasks if we upped the value. */
737 sk->sk_write_space(sk);
738 break;
739
740 case SO_SNDBUFFORCE:
741 if (!capable(CAP_NET_ADMIN)) {
742 ret = -EPERM;
743 break;
744 }
745 goto set_sndbuf;
746
747 case SO_RCVBUF:
748 /* Don't error on this BSD doesn't and if you think
749 * about it this is right. Otherwise apps have to
750 * play 'guess the biggest size' games. RCVBUF/SNDBUF
751 * are treated in BSD as hints
752 */
753 val = min_t(u32, val, sysctl_rmem_max);
754 set_rcvbuf:
755 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
756 /*
757 * We double it on the way in to account for
758 * "struct sk_buff" etc. overhead. Applications
759 * assume that the SO_RCVBUF setting they make will
760 * allow that much actual data to be received on that
761 * socket.
762 *
763 * Applications are unaware that "struct sk_buff" and
764 * other overheads allocate from the receive buffer
765 * during socket buffer allocation.
766 *
767 * And after considering the possible alternatives,
768 * returning the value we actually used in getsockopt
769 * is the most desirable behavior.
770 */
771 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
772 break;
773
774 case SO_RCVBUFFORCE:
775 if (!capable(CAP_NET_ADMIN)) {
776 ret = -EPERM;
777 break;
778 }
779 goto set_rcvbuf;
780
781 case SO_KEEPALIVE:
782 #ifdef CONFIG_INET
783 if (sk->sk_protocol == IPPROTO_TCP &&
784 sk->sk_type == SOCK_STREAM)
785 tcp_set_keepalive(sk, valbool);
786 #endif
787 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
788 break;
789
790 case SO_OOBINLINE:
791 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
792 break;
793
794 case SO_NO_CHECK:
795 sk->sk_no_check_tx = valbool;
796 break;
797
798 case SO_PRIORITY:
799 if ((val >= 0 && val <= 6) ||
800 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
801 sk->sk_priority = val;
802 else
803 ret = -EPERM;
804 break;
805
806 case SO_LINGER:
807 if (optlen < sizeof(ling)) {
808 ret = -EINVAL; /* 1003.1g */
809 break;
810 }
811 if (copy_from_user(&ling, optval, sizeof(ling))) {
812 ret = -EFAULT;
813 break;
814 }
815 if (!ling.l_onoff)
816 sock_reset_flag(sk, SOCK_LINGER);
817 else {
818 #if (BITS_PER_LONG == 32)
819 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
820 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
821 else
822 #endif
823 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
824 sock_set_flag(sk, SOCK_LINGER);
825 }
826 break;
827
828 case SO_BSDCOMPAT:
829 sock_warn_obsolete_bsdism("setsockopt");
830 break;
831
832 case SO_PASSCRED:
833 if (valbool)
834 set_bit(SOCK_PASSCRED, &sock->flags);
835 else
836 clear_bit(SOCK_PASSCRED, &sock->flags);
837 break;
838
839 case SO_TIMESTAMP:
840 case SO_TIMESTAMPNS:
841 if (valbool) {
842 if (optname == SO_TIMESTAMP)
843 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
844 else
845 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
846 sock_set_flag(sk, SOCK_RCVTSTAMP);
847 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
848 } else {
849 sock_reset_flag(sk, SOCK_RCVTSTAMP);
850 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
851 }
852 break;
853
854 case SO_TIMESTAMPING:
855 if (val & ~SOF_TIMESTAMPING_MASK) {
856 ret = -EINVAL;
857 break;
858 }
859
860 if (val & SOF_TIMESTAMPING_OPT_ID &&
861 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
862 if (sk->sk_protocol == IPPROTO_TCP &&
863 sk->sk_type == SOCK_STREAM) {
864 if (sk->sk_state != TCP_ESTABLISHED) {
865 ret = -EINVAL;
866 break;
867 }
868 sk->sk_tskey = tcp_sk(sk)->snd_una;
869 } else {
870 sk->sk_tskey = 0;
871 }
872 }
873 sk->sk_tsflags = val;
874 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
875 sock_enable_timestamp(sk,
876 SOCK_TIMESTAMPING_RX_SOFTWARE);
877 else
878 sock_disable_timestamp(sk,
879 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
880 break;
881
882 case SO_RCVLOWAT:
883 if (val < 0)
884 val = INT_MAX;
885 sk->sk_rcvlowat = val ? : 1;
886 break;
887
888 case SO_RCVTIMEO:
889 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
890 break;
891
892 case SO_SNDTIMEO:
893 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
894 break;
895
896 case SO_ATTACH_FILTER:
897 ret = -EINVAL;
898 if (optlen == sizeof(struct sock_fprog)) {
899 struct sock_fprog fprog;
900
901 ret = -EFAULT;
902 if (copy_from_user(&fprog, optval, sizeof(fprog)))
903 break;
904
905 ret = sk_attach_filter(&fprog, sk);
906 }
907 break;
908
909 case SO_ATTACH_BPF:
910 ret = -EINVAL;
911 if (optlen == sizeof(u32)) {
912 u32 ufd;
913
914 ret = -EFAULT;
915 if (copy_from_user(&ufd, optval, sizeof(ufd)))
916 break;
917
918 ret = sk_attach_bpf(ufd, sk);
919 }
920 break;
921
922 case SO_DETACH_FILTER:
923 ret = sk_detach_filter(sk);
924 break;
925
926 case SO_LOCK_FILTER:
927 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
928 ret = -EPERM;
929 else
930 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
931 break;
932
933 case SO_PASSSEC:
934 if (valbool)
935 set_bit(SOCK_PASSSEC, &sock->flags);
936 else
937 clear_bit(SOCK_PASSSEC, &sock->flags);
938 break;
939 case SO_MARK:
940 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
941 ret = -EPERM;
942 else
943 sk->sk_mark = val;
944 break;
945
946 case SO_RXQ_OVFL:
947 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
948 break;
949
950 case SO_WIFI_STATUS:
951 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
952 break;
953
954 case SO_PEEK_OFF:
955 if (sock->ops->set_peek_off)
956 ret = sock->ops->set_peek_off(sk, val);
957 else
958 ret = -EOPNOTSUPP;
959 break;
960
961 case SO_NOFCS:
962 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
963 break;
964
965 case SO_SELECT_ERR_QUEUE:
966 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
967 break;
968
969 #ifdef CONFIG_NET_RX_BUSY_POLL
970 case SO_BUSY_POLL:
971 /* allow unprivileged users to decrease the value */
972 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
973 ret = -EPERM;
974 else {
975 if (val < 0)
976 ret = -EINVAL;
977 else
978 sk->sk_ll_usec = val;
979 }
980 break;
981 #endif
982
983 case SO_MAX_PACING_RATE:
984 sk->sk_max_pacing_rate = val;
985 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
986 sk->sk_max_pacing_rate);
987 break;
988
989 default:
990 ret = -ENOPROTOOPT;
991 break;
992 }
993 release_sock(sk);
994 return ret;
995 }
996 EXPORT_SYMBOL(sock_setsockopt);
997
998
999 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1000 struct ucred *ucred)
1001 {
1002 ucred->pid = pid_vnr(pid);
1003 ucred->uid = ucred->gid = -1;
1004 if (cred) {
1005 struct user_namespace *current_ns = current_user_ns();
1006
1007 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1008 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1009 }
1010 }
1011
1012 int sock_getsockopt(struct socket *sock, int level, int optname,
1013 char __user *optval, int __user *optlen)
1014 {
1015 struct sock *sk = sock->sk;
1016
1017 union {
1018 int val;
1019 struct linger ling;
1020 struct timeval tm;
1021 } v;
1022
1023 int lv = sizeof(int);
1024 int len;
1025
1026 if (get_user(len, optlen))
1027 return -EFAULT;
1028 if (len < 0)
1029 return -EINVAL;
1030
1031 memset(&v, 0, sizeof(v));
1032
1033 switch (optname) {
1034 case SO_DEBUG:
1035 v.val = sock_flag(sk, SOCK_DBG);
1036 break;
1037
1038 case SO_DONTROUTE:
1039 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1040 break;
1041
1042 case SO_BROADCAST:
1043 v.val = sock_flag(sk, SOCK_BROADCAST);
1044 break;
1045
1046 case SO_SNDBUF:
1047 v.val = sk->sk_sndbuf;
1048 break;
1049
1050 case SO_RCVBUF:
1051 v.val = sk->sk_rcvbuf;
1052 break;
1053
1054 case SO_REUSEADDR:
1055 v.val = sk->sk_reuse;
1056 break;
1057
1058 case SO_REUSEPORT:
1059 v.val = sk->sk_reuseport;
1060 break;
1061
1062 case SO_KEEPALIVE:
1063 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1064 break;
1065
1066 case SO_TYPE:
1067 v.val = sk->sk_type;
1068 break;
1069
1070 case SO_PROTOCOL:
1071 v.val = sk->sk_protocol;
1072 break;
1073
1074 case SO_DOMAIN:
1075 v.val = sk->sk_family;
1076 break;
1077
1078 case SO_ERROR:
1079 v.val = -sock_error(sk);
1080 if (v.val == 0)
1081 v.val = xchg(&sk->sk_err_soft, 0);
1082 break;
1083
1084 case SO_OOBINLINE:
1085 v.val = sock_flag(sk, SOCK_URGINLINE);
1086 break;
1087
1088 case SO_NO_CHECK:
1089 v.val = sk->sk_no_check_tx;
1090 break;
1091
1092 case SO_PRIORITY:
1093 v.val = sk->sk_priority;
1094 break;
1095
1096 case SO_LINGER:
1097 lv = sizeof(v.ling);
1098 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1099 v.ling.l_linger = sk->sk_lingertime / HZ;
1100 break;
1101
1102 case SO_BSDCOMPAT:
1103 sock_warn_obsolete_bsdism("getsockopt");
1104 break;
1105
1106 case SO_TIMESTAMP:
1107 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1108 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1109 break;
1110
1111 case SO_TIMESTAMPNS:
1112 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1113 break;
1114
1115 case SO_TIMESTAMPING:
1116 v.val = sk->sk_tsflags;
1117 break;
1118
1119 case SO_RCVTIMEO:
1120 lv = sizeof(struct timeval);
1121 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1122 v.tm.tv_sec = 0;
1123 v.tm.tv_usec = 0;
1124 } else {
1125 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1126 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1127 }
1128 break;
1129
1130 case SO_SNDTIMEO:
1131 lv = sizeof(struct timeval);
1132 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1133 v.tm.tv_sec = 0;
1134 v.tm.tv_usec = 0;
1135 } else {
1136 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1137 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1138 }
1139 break;
1140
1141 case SO_RCVLOWAT:
1142 v.val = sk->sk_rcvlowat;
1143 break;
1144
1145 case SO_SNDLOWAT:
1146 v.val = 1;
1147 break;
1148
1149 case SO_PASSCRED:
1150 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1151 break;
1152
1153 case SO_PEERCRED:
1154 {
1155 struct ucred peercred;
1156 if (len > sizeof(peercred))
1157 len = sizeof(peercred);
1158 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1159 if (copy_to_user(optval, &peercred, len))
1160 return -EFAULT;
1161 goto lenout;
1162 }
1163
1164 case SO_PEERNAME:
1165 {
1166 char address[128];
1167
1168 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1169 return -ENOTCONN;
1170 if (lv < len)
1171 return -EINVAL;
1172 if (copy_to_user(optval, address, len))
1173 return -EFAULT;
1174 goto lenout;
1175 }
1176
1177 /* Dubious BSD thing... Probably nobody even uses it, but
1178 * the UNIX standard wants it for whatever reason... -DaveM
1179 */
1180 case SO_ACCEPTCONN:
1181 v.val = sk->sk_state == TCP_LISTEN;
1182 break;
1183
1184 case SO_PASSSEC:
1185 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1186 break;
1187
1188 case SO_PEERSEC:
1189 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1190
1191 case SO_MARK:
1192 v.val = sk->sk_mark;
1193 break;
1194
1195 case SO_RXQ_OVFL:
1196 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1197 break;
1198
1199 case SO_WIFI_STATUS:
1200 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1201 break;
1202
1203 case SO_PEEK_OFF:
1204 if (!sock->ops->set_peek_off)
1205 return -EOPNOTSUPP;
1206
1207 v.val = sk->sk_peek_off;
1208 break;
1209 case SO_NOFCS:
1210 v.val = sock_flag(sk, SOCK_NOFCS);
1211 break;
1212
1213 case SO_BINDTODEVICE:
1214 return sock_getbindtodevice(sk, optval, optlen, len);
1215
1216 case SO_GET_FILTER:
1217 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1218 if (len < 0)
1219 return len;
1220
1221 goto lenout;
1222
1223 case SO_LOCK_FILTER:
1224 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1225 break;
1226
1227 case SO_BPF_EXTENSIONS:
1228 v.val = bpf_tell_extensions();
1229 break;
1230
1231 case SO_SELECT_ERR_QUEUE:
1232 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1233 break;
1234
1235 #ifdef CONFIG_NET_RX_BUSY_POLL
1236 case SO_BUSY_POLL:
1237 v.val = sk->sk_ll_usec;
1238 break;
1239 #endif
1240
1241 case SO_MAX_PACING_RATE:
1242 v.val = sk->sk_max_pacing_rate;
1243 break;
1244
1245 case SO_INCOMING_CPU:
1246 v.val = sk->sk_incoming_cpu;
1247 break;
1248
1249 default:
1250 /* We implement the SO_SNDLOWAT etc to not be settable
1251 * (1003.1g 7).
1252 */
1253 return -ENOPROTOOPT;
1254 }
1255
1256 if (len > lv)
1257 len = lv;
1258 if (copy_to_user(optval, &v, len))
1259 return -EFAULT;
1260 lenout:
1261 if (put_user(len, optlen))
1262 return -EFAULT;
1263 return 0;
1264 }
1265
1266 /*
1267 * Initialize an sk_lock.
1268 *
1269 * (We also register the sk_lock with the lock validator.)
1270 */
1271 static inline void sock_lock_init(struct sock *sk)
1272 {
1273 sock_lock_init_class_and_name(sk,
1274 af_family_slock_key_strings[sk->sk_family],
1275 af_family_slock_keys + sk->sk_family,
1276 af_family_key_strings[sk->sk_family],
1277 af_family_keys + sk->sk_family);
1278 }
1279
1280 /*
1281 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1282 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1283 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1284 */
1285 static void sock_copy(struct sock *nsk, const struct sock *osk)
1286 {
1287 #ifdef CONFIG_SECURITY_NETWORK
1288 void *sptr = nsk->sk_security;
1289 #endif
1290 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1291
1292 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1293 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1294
1295 #ifdef CONFIG_SECURITY_NETWORK
1296 nsk->sk_security = sptr;
1297 security_sk_clone(osk, nsk);
1298 #endif
1299 }
1300
1301 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1302 {
1303 unsigned long nulls1, nulls2;
1304
1305 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1306 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1307 if (nulls1 > nulls2)
1308 swap(nulls1, nulls2);
1309
1310 if (nulls1 != 0)
1311 memset((char *)sk, 0, nulls1);
1312 memset((char *)sk + nulls1 + sizeof(void *), 0,
1313 nulls2 - nulls1 - sizeof(void *));
1314 memset((char *)sk + nulls2 + sizeof(void *), 0,
1315 size - nulls2 - sizeof(void *));
1316 }
1317 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1318
1319 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1320 int family)
1321 {
1322 struct sock *sk;
1323 struct kmem_cache *slab;
1324
1325 slab = prot->slab;
1326 if (slab != NULL) {
1327 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1328 if (!sk)
1329 return sk;
1330 if (priority & __GFP_ZERO) {
1331 if (prot->clear_sk)
1332 prot->clear_sk(sk, prot->obj_size);
1333 else
1334 sk_prot_clear_nulls(sk, prot->obj_size);
1335 }
1336 } else
1337 sk = kmalloc(prot->obj_size, priority);
1338
1339 if (sk != NULL) {
1340 kmemcheck_annotate_bitfield(sk, flags);
1341
1342 if (security_sk_alloc(sk, family, priority))
1343 goto out_free;
1344
1345 if (!try_module_get(prot->owner))
1346 goto out_free_sec;
1347 sk_tx_queue_clear(sk);
1348 }
1349
1350 return sk;
1351
1352 out_free_sec:
1353 security_sk_free(sk);
1354 out_free:
1355 if (slab != NULL)
1356 kmem_cache_free(slab, sk);
1357 else
1358 kfree(sk);
1359 return NULL;
1360 }
1361
1362 static void sk_prot_free(struct proto *prot, struct sock *sk)
1363 {
1364 struct kmem_cache *slab;
1365 struct module *owner;
1366
1367 owner = prot->owner;
1368 slab = prot->slab;
1369
1370 security_sk_free(sk);
1371 if (slab != NULL)
1372 kmem_cache_free(slab, sk);
1373 else
1374 kfree(sk);
1375 module_put(owner);
1376 }
1377
1378 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
1379 void sock_update_netprioidx(struct sock *sk)
1380 {
1381 if (in_interrupt())
1382 return;
1383
1384 sk->sk_cgrp_prioidx = task_netprioidx(current);
1385 }
1386 EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1387 #endif
1388
1389 /**
1390 * sk_alloc - All socket objects are allocated here
1391 * @net: the applicable net namespace
1392 * @family: protocol family
1393 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1394 * @prot: struct proto associated with this new sock instance
1395 */
1396 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1397 struct proto *prot)
1398 {
1399 struct sock *sk;
1400
1401 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1402 if (sk) {
1403 sk->sk_family = family;
1404 /*
1405 * See comment in struct sock definition to understand
1406 * why we need sk_prot_creator -acme
1407 */
1408 sk->sk_prot = sk->sk_prot_creator = prot;
1409 sock_lock_init(sk);
1410 sock_net_set(sk, get_net(net));
1411 atomic_set(&sk->sk_wmem_alloc, 1);
1412
1413 sock_update_classid(sk);
1414 sock_update_netprioidx(sk);
1415 }
1416
1417 return sk;
1418 }
1419 EXPORT_SYMBOL(sk_alloc);
1420
1421 static void __sk_free(struct sock *sk)
1422 {
1423 struct sk_filter *filter;
1424
1425 if (sk->sk_destruct)
1426 sk->sk_destruct(sk);
1427
1428 filter = rcu_dereference_check(sk->sk_filter,
1429 atomic_read(&sk->sk_wmem_alloc) == 0);
1430 if (filter) {
1431 sk_filter_uncharge(sk, filter);
1432 RCU_INIT_POINTER(sk->sk_filter, NULL);
1433 }
1434
1435 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1436
1437 if (atomic_read(&sk->sk_omem_alloc))
1438 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1439 __func__, atomic_read(&sk->sk_omem_alloc));
1440
1441 if (sk->sk_peer_cred)
1442 put_cred(sk->sk_peer_cred);
1443 put_pid(sk->sk_peer_pid);
1444 put_net(sock_net(sk));
1445 sk_prot_free(sk->sk_prot_creator, sk);
1446 }
1447
1448 void sk_free(struct sock *sk)
1449 {
1450 /*
1451 * We subtract one from sk_wmem_alloc and can know if
1452 * some packets are still in some tx queue.
1453 * If not null, sock_wfree() will call __sk_free(sk) later
1454 */
1455 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1456 __sk_free(sk);
1457 }
1458 EXPORT_SYMBOL(sk_free);
1459
1460 /*
1461 * Last sock_put should drop reference to sk->sk_net. It has already
1462 * been dropped in sk_change_net. Taking reference to stopping namespace
1463 * is not an option.
1464 * Take reference to a socket to remove it from hash _alive_ and after that
1465 * destroy it in the context of init_net.
1466 */
1467 void sk_release_kernel(struct sock *sk)
1468 {
1469 if (sk == NULL || sk->sk_socket == NULL)
1470 return;
1471
1472 sock_hold(sk);
1473 sock_release(sk->sk_socket);
1474 sock_net_set(sk, get_net(&init_net));
1475 sock_put(sk);
1476 }
1477 EXPORT_SYMBOL(sk_release_kernel);
1478
1479 static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1480 {
1481 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1482 sock_update_memcg(newsk);
1483 }
1484
1485 /**
1486 * sk_clone_lock - clone a socket, and lock its clone
1487 * @sk: the socket to clone
1488 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1489 *
1490 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1491 */
1492 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1493 {
1494 struct sock *newsk;
1495 bool is_charged = true;
1496
1497 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1498 if (newsk != NULL) {
1499 struct sk_filter *filter;
1500
1501 sock_copy(newsk, sk);
1502
1503 /* SANITY */
1504 get_net(sock_net(newsk));
1505 sk_node_init(&newsk->sk_node);
1506 sock_lock_init(newsk);
1507 bh_lock_sock(newsk);
1508 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1509 newsk->sk_backlog.len = 0;
1510
1511 atomic_set(&newsk->sk_rmem_alloc, 0);
1512 /*
1513 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1514 */
1515 atomic_set(&newsk->sk_wmem_alloc, 1);
1516 atomic_set(&newsk->sk_omem_alloc, 0);
1517 skb_queue_head_init(&newsk->sk_receive_queue);
1518 skb_queue_head_init(&newsk->sk_write_queue);
1519
1520 spin_lock_init(&newsk->sk_dst_lock);
1521 rwlock_init(&newsk->sk_callback_lock);
1522 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1523 af_callback_keys + newsk->sk_family,
1524 af_family_clock_key_strings[newsk->sk_family]);
1525
1526 newsk->sk_dst_cache = NULL;
1527 newsk->sk_wmem_queued = 0;
1528 newsk->sk_forward_alloc = 0;
1529 newsk->sk_send_head = NULL;
1530 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1531
1532 sock_reset_flag(newsk, SOCK_DONE);
1533 skb_queue_head_init(&newsk->sk_error_queue);
1534
1535 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1536 if (filter != NULL)
1537 /* though it's an empty new sock, the charging may fail
1538 * if sysctl_optmem_max was changed between creation of
1539 * original socket and cloning
1540 */
1541 is_charged = sk_filter_charge(newsk, filter);
1542
1543 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) {
1544 /* It is still raw copy of parent, so invalidate
1545 * destructor and make plain sk_free() */
1546 newsk->sk_destruct = NULL;
1547 bh_unlock_sock(newsk);
1548 sk_free(newsk);
1549 newsk = NULL;
1550 goto out;
1551 }
1552
1553 newsk->sk_err = 0;
1554 newsk->sk_priority = 0;
1555 newsk->sk_incoming_cpu = raw_smp_processor_id();
1556 atomic64_set(&newsk->sk_cookie, 0);
1557 /*
1558 * Before updating sk_refcnt, we must commit prior changes to memory
1559 * (Documentation/RCU/rculist_nulls.txt for details)
1560 */
1561 smp_wmb();
1562 atomic_set(&newsk->sk_refcnt, 2);
1563
1564 /*
1565 * Increment the counter in the same struct proto as the master
1566 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1567 * is the same as sk->sk_prot->socks, as this field was copied
1568 * with memcpy).
1569 *
1570 * This _changes_ the previous behaviour, where
1571 * tcp_create_openreq_child always was incrementing the
1572 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1573 * to be taken into account in all callers. -acme
1574 */
1575 sk_refcnt_debug_inc(newsk);
1576 sk_set_socket(newsk, NULL);
1577 newsk->sk_wq = NULL;
1578
1579 sk_update_clone(sk, newsk);
1580
1581 if (newsk->sk_prot->sockets_allocated)
1582 sk_sockets_allocated_inc(newsk);
1583
1584 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1585 net_enable_timestamp();
1586 }
1587 out:
1588 return newsk;
1589 }
1590 EXPORT_SYMBOL_GPL(sk_clone_lock);
1591
1592 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1593 {
1594 __sk_dst_set(sk, dst);
1595 sk->sk_route_caps = dst->dev->features;
1596 if (sk->sk_route_caps & NETIF_F_GSO)
1597 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1598 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1599 if (sk_can_gso(sk)) {
1600 if (dst->header_len) {
1601 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1602 } else {
1603 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1604 sk->sk_gso_max_size = dst->dev->gso_max_size;
1605 sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1606 }
1607 }
1608 }
1609 EXPORT_SYMBOL_GPL(sk_setup_caps);
1610
1611 /*
1612 * Simple resource managers for sockets.
1613 */
1614
1615
1616 /*
1617 * Write buffer destructor automatically called from kfree_skb.
1618 */
1619 void sock_wfree(struct sk_buff *skb)
1620 {
1621 struct sock *sk = skb->sk;
1622 unsigned int len = skb->truesize;
1623
1624 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1625 /*
1626 * Keep a reference on sk_wmem_alloc, this will be released
1627 * after sk_write_space() call
1628 */
1629 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1630 sk->sk_write_space(sk);
1631 len = 1;
1632 }
1633 /*
1634 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1635 * could not do because of in-flight packets
1636 */
1637 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1638 __sk_free(sk);
1639 }
1640 EXPORT_SYMBOL(sock_wfree);
1641
1642 void skb_orphan_partial(struct sk_buff *skb)
1643 {
1644 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1645 * so we do not completely orphan skb, but transfert all
1646 * accounted bytes but one, to avoid unexpected reorders.
1647 */
1648 if (skb->destructor == sock_wfree
1649 #ifdef CONFIG_INET
1650 || skb->destructor == tcp_wfree
1651 #endif
1652 ) {
1653 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1654 skb->truesize = 1;
1655 } else {
1656 skb_orphan(skb);
1657 }
1658 }
1659 EXPORT_SYMBOL(skb_orphan_partial);
1660
1661 /*
1662 * Read buffer destructor automatically called from kfree_skb.
1663 */
1664 void sock_rfree(struct sk_buff *skb)
1665 {
1666 struct sock *sk = skb->sk;
1667 unsigned int len = skb->truesize;
1668
1669 atomic_sub(len, &sk->sk_rmem_alloc);
1670 sk_mem_uncharge(sk, len);
1671 }
1672 EXPORT_SYMBOL(sock_rfree);
1673
1674 /*
1675 * Buffer destructor for skbs that are not used directly in read or write
1676 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1677 */
1678 void sock_efree(struct sk_buff *skb)
1679 {
1680 sock_put(skb->sk);
1681 }
1682 EXPORT_SYMBOL(sock_efree);
1683
1684 kuid_t sock_i_uid(struct sock *sk)
1685 {
1686 kuid_t uid;
1687
1688 read_lock_bh(&sk->sk_callback_lock);
1689 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1690 read_unlock_bh(&sk->sk_callback_lock);
1691 return uid;
1692 }
1693 EXPORT_SYMBOL(sock_i_uid);
1694
1695 unsigned long sock_i_ino(struct sock *sk)
1696 {
1697 unsigned long ino;
1698
1699 read_lock_bh(&sk->sk_callback_lock);
1700 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1701 read_unlock_bh(&sk->sk_callback_lock);
1702 return ino;
1703 }
1704 EXPORT_SYMBOL(sock_i_ino);
1705
1706 /*
1707 * Allocate a skb from the socket's send buffer.
1708 */
1709 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1710 gfp_t priority)
1711 {
1712 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1713 struct sk_buff *skb = alloc_skb(size, priority);
1714 if (skb) {
1715 skb_set_owner_w(skb, sk);
1716 return skb;
1717 }
1718 }
1719 return NULL;
1720 }
1721 EXPORT_SYMBOL(sock_wmalloc);
1722
1723 /*
1724 * Allocate a memory block from the socket's option memory buffer.
1725 */
1726 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1727 {
1728 if ((unsigned int)size <= sysctl_optmem_max &&
1729 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1730 void *mem;
1731 /* First do the add, to avoid the race if kmalloc
1732 * might sleep.
1733 */
1734 atomic_add(size, &sk->sk_omem_alloc);
1735 mem = kmalloc(size, priority);
1736 if (mem)
1737 return mem;
1738 atomic_sub(size, &sk->sk_omem_alloc);
1739 }
1740 return NULL;
1741 }
1742 EXPORT_SYMBOL(sock_kmalloc);
1743
1744 /* Free an option memory block. Note, we actually want the inline
1745 * here as this allows gcc to detect the nullify and fold away the
1746 * condition entirely.
1747 */
1748 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1749 const bool nullify)
1750 {
1751 if (WARN_ON_ONCE(!mem))
1752 return;
1753 if (nullify)
1754 kzfree(mem);
1755 else
1756 kfree(mem);
1757 atomic_sub(size, &sk->sk_omem_alloc);
1758 }
1759
1760 void sock_kfree_s(struct sock *sk, void *mem, int size)
1761 {
1762 __sock_kfree_s(sk, mem, size, false);
1763 }
1764 EXPORT_SYMBOL(sock_kfree_s);
1765
1766 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1767 {
1768 __sock_kfree_s(sk, mem, size, true);
1769 }
1770 EXPORT_SYMBOL(sock_kzfree_s);
1771
1772 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1773 I think, these locks should be removed for datagram sockets.
1774 */
1775 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1776 {
1777 DEFINE_WAIT(wait);
1778
1779 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1780 for (;;) {
1781 if (!timeo)
1782 break;
1783 if (signal_pending(current))
1784 break;
1785 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1786 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1787 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1788 break;
1789 if (sk->sk_shutdown & SEND_SHUTDOWN)
1790 break;
1791 if (sk->sk_err)
1792 break;
1793 timeo = schedule_timeout(timeo);
1794 }
1795 finish_wait(sk_sleep(sk), &wait);
1796 return timeo;
1797 }
1798
1799
1800 /*
1801 * Generic send/receive buffer handlers
1802 */
1803
1804 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1805 unsigned long data_len, int noblock,
1806 int *errcode, int max_page_order)
1807 {
1808 struct sk_buff *skb;
1809 long timeo;
1810 int err;
1811
1812 timeo = sock_sndtimeo(sk, noblock);
1813 for (;;) {
1814 err = sock_error(sk);
1815 if (err != 0)
1816 goto failure;
1817
1818 err = -EPIPE;
1819 if (sk->sk_shutdown & SEND_SHUTDOWN)
1820 goto failure;
1821
1822 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1823 break;
1824
1825 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1826 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1827 err = -EAGAIN;
1828 if (!timeo)
1829 goto failure;
1830 if (signal_pending(current))
1831 goto interrupted;
1832 timeo = sock_wait_for_wmem(sk, timeo);
1833 }
1834 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1835 errcode, sk->sk_allocation);
1836 if (skb)
1837 skb_set_owner_w(skb, sk);
1838 return skb;
1839
1840 interrupted:
1841 err = sock_intr_errno(timeo);
1842 failure:
1843 *errcode = err;
1844 return NULL;
1845 }
1846 EXPORT_SYMBOL(sock_alloc_send_pskb);
1847
1848 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1849 int noblock, int *errcode)
1850 {
1851 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1852 }
1853 EXPORT_SYMBOL(sock_alloc_send_skb);
1854
1855 /* On 32bit arches, an skb frag is limited to 2^15 */
1856 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1857
1858 /**
1859 * skb_page_frag_refill - check that a page_frag contains enough room
1860 * @sz: minimum size of the fragment we want to get
1861 * @pfrag: pointer to page_frag
1862 * @gfp: priority for memory allocation
1863 *
1864 * Note: While this allocator tries to use high order pages, there is
1865 * no guarantee that allocations succeed. Therefore, @sz MUST be
1866 * less or equal than PAGE_SIZE.
1867 */
1868 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1869 {
1870 if (pfrag->page) {
1871 if (atomic_read(&pfrag->page->_count) == 1) {
1872 pfrag->offset = 0;
1873 return true;
1874 }
1875 if (pfrag->offset + sz <= pfrag->size)
1876 return true;
1877 put_page(pfrag->page);
1878 }
1879
1880 pfrag->offset = 0;
1881 if (SKB_FRAG_PAGE_ORDER) {
1882 pfrag->page = alloc_pages((gfp & ~__GFP_WAIT) | __GFP_COMP |
1883 __GFP_NOWARN | __GFP_NORETRY,
1884 SKB_FRAG_PAGE_ORDER);
1885 if (likely(pfrag->page)) {
1886 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1887 return true;
1888 }
1889 }
1890 pfrag->page = alloc_page(gfp);
1891 if (likely(pfrag->page)) {
1892 pfrag->size = PAGE_SIZE;
1893 return true;
1894 }
1895 return false;
1896 }
1897 EXPORT_SYMBOL(skb_page_frag_refill);
1898
1899 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1900 {
1901 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1902 return true;
1903
1904 sk_enter_memory_pressure(sk);
1905 sk_stream_moderate_sndbuf(sk);
1906 return false;
1907 }
1908 EXPORT_SYMBOL(sk_page_frag_refill);
1909
1910 static void __lock_sock(struct sock *sk)
1911 __releases(&sk->sk_lock.slock)
1912 __acquires(&sk->sk_lock.slock)
1913 {
1914 DEFINE_WAIT(wait);
1915
1916 for (;;) {
1917 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1918 TASK_UNINTERRUPTIBLE);
1919 spin_unlock_bh(&sk->sk_lock.slock);
1920 schedule();
1921 spin_lock_bh(&sk->sk_lock.slock);
1922 if (!sock_owned_by_user(sk))
1923 break;
1924 }
1925 finish_wait(&sk->sk_lock.wq, &wait);
1926 }
1927
1928 static void __release_sock(struct sock *sk)
1929 __releases(&sk->sk_lock.slock)
1930 __acquires(&sk->sk_lock.slock)
1931 {
1932 struct sk_buff *skb = sk->sk_backlog.head;
1933
1934 do {
1935 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1936 bh_unlock_sock(sk);
1937
1938 do {
1939 struct sk_buff *next = skb->next;
1940
1941 prefetch(next);
1942 WARN_ON_ONCE(skb_dst_is_noref(skb));
1943 skb->next = NULL;
1944 sk_backlog_rcv(sk, skb);
1945
1946 /*
1947 * We are in process context here with softirqs
1948 * disabled, use cond_resched_softirq() to preempt.
1949 * This is safe to do because we've taken the backlog
1950 * queue private:
1951 */
1952 cond_resched_softirq();
1953
1954 skb = next;
1955 } while (skb != NULL);
1956
1957 bh_lock_sock(sk);
1958 } while ((skb = sk->sk_backlog.head) != NULL);
1959
1960 /*
1961 * Doing the zeroing here guarantee we can not loop forever
1962 * while a wild producer attempts to flood us.
1963 */
1964 sk->sk_backlog.len = 0;
1965 }
1966
1967 /**
1968 * sk_wait_data - wait for data to arrive at sk_receive_queue
1969 * @sk: sock to wait on
1970 * @timeo: for how long
1971 *
1972 * Now socket state including sk->sk_err is changed only under lock,
1973 * hence we may omit checks after joining wait queue.
1974 * We check receive queue before schedule() only as optimization;
1975 * it is very likely that release_sock() added new data.
1976 */
1977 int sk_wait_data(struct sock *sk, long *timeo)
1978 {
1979 int rc;
1980 DEFINE_WAIT(wait);
1981
1982 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1983 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1984 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1985 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1986 finish_wait(sk_sleep(sk), &wait);
1987 return rc;
1988 }
1989 EXPORT_SYMBOL(sk_wait_data);
1990
1991 /**
1992 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1993 * @sk: socket
1994 * @size: memory size to allocate
1995 * @kind: allocation type
1996 *
1997 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1998 * rmem allocation. This function assumes that protocols which have
1999 * memory_pressure use sk_wmem_queued as write buffer accounting.
2000 */
2001 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2002 {
2003 struct proto *prot = sk->sk_prot;
2004 int amt = sk_mem_pages(size);
2005 long allocated;
2006 int parent_status = UNDER_LIMIT;
2007
2008 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2009
2010 allocated = sk_memory_allocated_add(sk, amt, &parent_status);
2011
2012 /* Under limit. */
2013 if (parent_status == UNDER_LIMIT &&
2014 allocated <= sk_prot_mem_limits(sk, 0)) {
2015 sk_leave_memory_pressure(sk);
2016 return 1;
2017 }
2018
2019 /* Under pressure. (we or our parents) */
2020 if ((parent_status > SOFT_LIMIT) ||
2021 allocated > sk_prot_mem_limits(sk, 1))
2022 sk_enter_memory_pressure(sk);
2023
2024 /* Over hard limit (we or our parents) */
2025 if ((parent_status == OVER_LIMIT) ||
2026 (allocated > sk_prot_mem_limits(sk, 2)))
2027 goto suppress_allocation;
2028
2029 /* guarantee minimum buffer size under pressure */
2030 if (kind == SK_MEM_RECV) {
2031 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2032 return 1;
2033
2034 } else { /* SK_MEM_SEND */
2035 if (sk->sk_type == SOCK_STREAM) {
2036 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2037 return 1;
2038 } else if (atomic_read(&sk->sk_wmem_alloc) <
2039 prot->sysctl_wmem[0])
2040 return 1;
2041 }
2042
2043 if (sk_has_memory_pressure(sk)) {
2044 int alloc;
2045
2046 if (!sk_under_memory_pressure(sk))
2047 return 1;
2048 alloc = sk_sockets_allocated_read_positive(sk);
2049 if (sk_prot_mem_limits(sk, 2) > alloc *
2050 sk_mem_pages(sk->sk_wmem_queued +
2051 atomic_read(&sk->sk_rmem_alloc) +
2052 sk->sk_forward_alloc))
2053 return 1;
2054 }
2055
2056 suppress_allocation:
2057
2058 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2059 sk_stream_moderate_sndbuf(sk);
2060
2061 /* Fail only if socket is _under_ its sndbuf.
2062 * In this case we cannot block, so that we have to fail.
2063 */
2064 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2065 return 1;
2066 }
2067
2068 trace_sock_exceed_buf_limit(sk, prot, allocated);
2069
2070 /* Alas. Undo changes. */
2071 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2072
2073 sk_memory_allocated_sub(sk, amt);
2074
2075 return 0;
2076 }
2077 EXPORT_SYMBOL(__sk_mem_schedule);
2078
2079 /**
2080 * __sk_reclaim - reclaim memory_allocated
2081 * @sk: socket
2082 */
2083 void __sk_mem_reclaim(struct sock *sk)
2084 {
2085 sk_memory_allocated_sub(sk,
2086 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
2087 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
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 kfree(sk->sk_protinfo);
2273 }
2274
2275 void sk_send_sigurg(struct sock *sk)
2276 {
2277 if (sk->sk_socket && sk->sk_socket->file)
2278 if (send_sigurg(&sk->sk_socket->file->f_owner))
2279 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2280 }
2281 EXPORT_SYMBOL(sk_send_sigurg);
2282
2283 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2284 unsigned long expires)
2285 {
2286 if (!mod_timer(timer, expires))
2287 sock_hold(sk);
2288 }
2289 EXPORT_SYMBOL(sk_reset_timer);
2290
2291 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2292 {
2293 if (del_timer(timer))
2294 __sock_put(sk);
2295 }
2296 EXPORT_SYMBOL(sk_stop_timer);
2297
2298 void sock_init_data(struct socket *sock, struct sock *sk)
2299 {
2300 skb_queue_head_init(&sk->sk_receive_queue);
2301 skb_queue_head_init(&sk->sk_write_queue);
2302 skb_queue_head_init(&sk->sk_error_queue);
2303
2304 sk->sk_send_head = NULL;
2305
2306 init_timer(&sk->sk_timer);
2307
2308 sk->sk_allocation = GFP_KERNEL;
2309 sk->sk_rcvbuf = sysctl_rmem_default;
2310 sk->sk_sndbuf = sysctl_wmem_default;
2311 sk->sk_state = TCP_CLOSE;
2312 sk_set_socket(sk, sock);
2313
2314 sock_set_flag(sk, SOCK_ZAPPED);
2315
2316 if (sock) {
2317 sk->sk_type = sock->type;
2318 sk->sk_wq = sock->wq;
2319 sock->sk = sk;
2320 } else
2321 sk->sk_wq = NULL;
2322
2323 spin_lock_init(&sk->sk_dst_lock);
2324 rwlock_init(&sk->sk_callback_lock);
2325 lockdep_set_class_and_name(&sk->sk_callback_lock,
2326 af_callback_keys + sk->sk_family,
2327 af_family_clock_key_strings[sk->sk_family]);
2328
2329 sk->sk_state_change = sock_def_wakeup;
2330 sk->sk_data_ready = sock_def_readable;
2331 sk->sk_write_space = sock_def_write_space;
2332 sk->sk_error_report = sock_def_error_report;
2333 sk->sk_destruct = sock_def_destruct;
2334
2335 sk->sk_frag.page = NULL;
2336 sk->sk_frag.offset = 0;
2337 sk->sk_peek_off = -1;
2338
2339 sk->sk_peer_pid = NULL;
2340 sk->sk_peer_cred = NULL;
2341 sk->sk_write_pending = 0;
2342 sk->sk_rcvlowat = 1;
2343 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2344 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2345
2346 sk->sk_stamp = ktime_set(-1L, 0);
2347
2348 #ifdef CONFIG_NET_RX_BUSY_POLL
2349 sk->sk_napi_id = 0;
2350 sk->sk_ll_usec = sysctl_net_busy_read;
2351 #endif
2352
2353 sk->sk_max_pacing_rate = ~0U;
2354 sk->sk_pacing_rate = ~0U;
2355 /*
2356 * Before updating sk_refcnt, we must commit prior changes to memory
2357 * (Documentation/RCU/rculist_nulls.txt for details)
2358 */
2359 smp_wmb();
2360 atomic_set(&sk->sk_refcnt, 1);
2361 atomic_set(&sk->sk_drops, 0);
2362 }
2363 EXPORT_SYMBOL(sock_init_data);
2364
2365 void lock_sock_nested(struct sock *sk, int subclass)
2366 {
2367 might_sleep();
2368 spin_lock_bh(&sk->sk_lock.slock);
2369 if (sk->sk_lock.owned)
2370 __lock_sock(sk);
2371 sk->sk_lock.owned = 1;
2372 spin_unlock(&sk->sk_lock.slock);
2373 /*
2374 * The sk_lock has mutex_lock() semantics here:
2375 */
2376 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2377 local_bh_enable();
2378 }
2379 EXPORT_SYMBOL(lock_sock_nested);
2380
2381 void release_sock(struct sock *sk)
2382 {
2383 /*
2384 * The sk_lock has mutex_unlock() semantics:
2385 */
2386 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2387
2388 spin_lock_bh(&sk->sk_lock.slock);
2389 if (sk->sk_backlog.tail)
2390 __release_sock(sk);
2391
2392 /* Warning : release_cb() might need to release sk ownership,
2393 * ie call sock_release_ownership(sk) before us.
2394 */
2395 if (sk->sk_prot->release_cb)
2396 sk->sk_prot->release_cb(sk);
2397
2398 sock_release_ownership(sk);
2399 if (waitqueue_active(&sk->sk_lock.wq))
2400 wake_up(&sk->sk_lock.wq);
2401 spin_unlock_bh(&sk->sk_lock.slock);
2402 }
2403 EXPORT_SYMBOL(release_sock);
2404
2405 /**
2406 * lock_sock_fast - fast version of lock_sock
2407 * @sk: socket
2408 *
2409 * This version should be used for very small section, where process wont block
2410 * return false if fast path is taken
2411 * sk_lock.slock locked, owned = 0, BH disabled
2412 * return true if slow path is taken
2413 * sk_lock.slock unlocked, owned = 1, BH enabled
2414 */
2415 bool lock_sock_fast(struct sock *sk)
2416 {
2417 might_sleep();
2418 spin_lock_bh(&sk->sk_lock.slock);
2419
2420 if (!sk->sk_lock.owned)
2421 /*
2422 * Note : We must disable BH
2423 */
2424 return false;
2425
2426 __lock_sock(sk);
2427 sk->sk_lock.owned = 1;
2428 spin_unlock(&sk->sk_lock.slock);
2429 /*
2430 * The sk_lock has mutex_lock() semantics here:
2431 */
2432 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2433 local_bh_enable();
2434 return true;
2435 }
2436 EXPORT_SYMBOL(lock_sock_fast);
2437
2438 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2439 {
2440 struct timeval tv;
2441 if (!sock_flag(sk, SOCK_TIMESTAMP))
2442 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2443 tv = ktime_to_timeval(sk->sk_stamp);
2444 if (tv.tv_sec == -1)
2445 return -ENOENT;
2446 if (tv.tv_sec == 0) {
2447 sk->sk_stamp = ktime_get_real();
2448 tv = ktime_to_timeval(sk->sk_stamp);
2449 }
2450 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2451 }
2452 EXPORT_SYMBOL(sock_get_timestamp);
2453
2454 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2455 {
2456 struct timespec ts;
2457 if (!sock_flag(sk, SOCK_TIMESTAMP))
2458 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2459 ts = ktime_to_timespec(sk->sk_stamp);
2460 if (ts.tv_sec == -1)
2461 return -ENOENT;
2462 if (ts.tv_sec == 0) {
2463 sk->sk_stamp = ktime_get_real();
2464 ts = ktime_to_timespec(sk->sk_stamp);
2465 }
2466 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2467 }
2468 EXPORT_SYMBOL(sock_get_timestampns);
2469
2470 void sock_enable_timestamp(struct sock *sk, int flag)
2471 {
2472 if (!sock_flag(sk, flag)) {
2473 unsigned long previous_flags = sk->sk_flags;
2474
2475 sock_set_flag(sk, flag);
2476 /*
2477 * we just set one of the two flags which require net
2478 * time stamping, but time stamping might have been on
2479 * already because of the other one
2480 */
2481 if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2482 net_enable_timestamp();
2483 }
2484 }
2485
2486 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2487 int level, int type)
2488 {
2489 struct sock_exterr_skb *serr;
2490 struct sk_buff *skb;
2491 int copied, err;
2492
2493 err = -EAGAIN;
2494 skb = sock_dequeue_err_skb(sk);
2495 if (skb == NULL)
2496 goto out;
2497
2498 copied = skb->len;
2499 if (copied > len) {
2500 msg->msg_flags |= MSG_TRUNC;
2501 copied = len;
2502 }
2503 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2504 if (err)
2505 goto out_free_skb;
2506
2507 sock_recv_timestamp(msg, sk, skb);
2508
2509 serr = SKB_EXT_ERR(skb);
2510 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2511
2512 msg->msg_flags |= MSG_ERRQUEUE;
2513 err = copied;
2514
2515 out_free_skb:
2516 kfree_skb(skb);
2517 out:
2518 return err;
2519 }
2520 EXPORT_SYMBOL(sock_recv_errqueue);
2521
2522 /*
2523 * Get a socket option on an socket.
2524 *
2525 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2526 * asynchronous errors should be reported by getsockopt. We assume
2527 * this means if you specify SO_ERROR (otherwise whats the point of it).
2528 */
2529 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2530 char __user *optval, int __user *optlen)
2531 {
2532 struct sock *sk = sock->sk;
2533
2534 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2535 }
2536 EXPORT_SYMBOL(sock_common_getsockopt);
2537
2538 #ifdef CONFIG_COMPAT
2539 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2540 char __user *optval, int __user *optlen)
2541 {
2542 struct sock *sk = sock->sk;
2543
2544 if (sk->sk_prot->compat_getsockopt != NULL)
2545 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2546 optval, optlen);
2547 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2548 }
2549 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2550 #endif
2551
2552 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2553 int flags)
2554 {
2555 struct sock *sk = sock->sk;
2556 int addr_len = 0;
2557 int err;
2558
2559 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2560 flags & ~MSG_DONTWAIT, &addr_len);
2561 if (err >= 0)
2562 msg->msg_namelen = addr_len;
2563 return err;
2564 }
2565 EXPORT_SYMBOL(sock_common_recvmsg);
2566
2567 /*
2568 * Set socket options on an inet socket.
2569 */
2570 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2571 char __user *optval, unsigned int optlen)
2572 {
2573 struct sock *sk = sock->sk;
2574
2575 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2576 }
2577 EXPORT_SYMBOL(sock_common_setsockopt);
2578
2579 #ifdef CONFIG_COMPAT
2580 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2581 char __user *optval, unsigned int optlen)
2582 {
2583 struct sock *sk = sock->sk;
2584
2585 if (sk->sk_prot->compat_setsockopt != NULL)
2586 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2587 optval, optlen);
2588 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2589 }
2590 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2591 #endif
2592
2593 void sk_common_release(struct sock *sk)
2594 {
2595 if (sk->sk_prot->destroy)
2596 sk->sk_prot->destroy(sk);
2597
2598 /*
2599 * Observation: when sock_common_release is called, processes have
2600 * no access to socket. But net still has.
2601 * Step one, detach it from networking:
2602 *
2603 * A. Remove from hash tables.
2604 */
2605
2606 sk->sk_prot->unhash(sk);
2607
2608 /*
2609 * In this point socket cannot receive new packets, but it is possible
2610 * that some packets are in flight because some CPU runs receiver and
2611 * did hash table lookup before we unhashed socket. They will achieve
2612 * receive queue and will be purged by socket destructor.
2613 *
2614 * Also we still have packets pending on receive queue and probably,
2615 * our own packets waiting in device queues. sock_destroy will drain
2616 * receive queue, but transmitted packets will delay socket destruction
2617 * until the last reference will be released.
2618 */
2619
2620 sock_orphan(sk);
2621
2622 xfrm_sk_free_policy(sk);
2623
2624 sk_refcnt_debug_release(sk);
2625
2626 if (sk->sk_frag.page) {
2627 put_page(sk->sk_frag.page);
2628 sk->sk_frag.page = NULL;
2629 }
2630
2631 sock_put(sk);
2632 }
2633 EXPORT_SYMBOL(sk_common_release);
2634
2635 #ifdef CONFIG_PROC_FS
2636 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2637 struct prot_inuse {
2638 int val[PROTO_INUSE_NR];
2639 };
2640
2641 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2642
2643 #ifdef CONFIG_NET_NS
2644 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2645 {
2646 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2647 }
2648 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2649
2650 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2651 {
2652 int cpu, idx = prot->inuse_idx;
2653 int res = 0;
2654
2655 for_each_possible_cpu(cpu)
2656 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2657
2658 return res >= 0 ? res : 0;
2659 }
2660 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2661
2662 static int __net_init sock_inuse_init_net(struct net *net)
2663 {
2664 net->core.inuse = alloc_percpu(struct prot_inuse);
2665 return net->core.inuse ? 0 : -ENOMEM;
2666 }
2667
2668 static void __net_exit sock_inuse_exit_net(struct net *net)
2669 {
2670 free_percpu(net->core.inuse);
2671 }
2672
2673 static struct pernet_operations net_inuse_ops = {
2674 .init = sock_inuse_init_net,
2675 .exit = sock_inuse_exit_net,
2676 };
2677
2678 static __init int net_inuse_init(void)
2679 {
2680 if (register_pernet_subsys(&net_inuse_ops))
2681 panic("Cannot initialize net inuse counters");
2682
2683 return 0;
2684 }
2685
2686 core_initcall(net_inuse_init);
2687 #else
2688 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2689
2690 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2691 {
2692 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2693 }
2694 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2695
2696 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2697 {
2698 int cpu, idx = prot->inuse_idx;
2699 int res = 0;
2700
2701 for_each_possible_cpu(cpu)
2702 res += per_cpu(prot_inuse, cpu).val[idx];
2703
2704 return res >= 0 ? res : 0;
2705 }
2706 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2707 #endif
2708
2709 static void assign_proto_idx(struct proto *prot)
2710 {
2711 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2712
2713 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2714 pr_err("PROTO_INUSE_NR exhausted\n");
2715 return;
2716 }
2717
2718 set_bit(prot->inuse_idx, proto_inuse_idx);
2719 }
2720
2721 static void release_proto_idx(struct proto *prot)
2722 {
2723 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2724 clear_bit(prot->inuse_idx, proto_inuse_idx);
2725 }
2726 #else
2727 static inline void assign_proto_idx(struct proto *prot)
2728 {
2729 }
2730
2731 static inline void release_proto_idx(struct proto *prot)
2732 {
2733 }
2734 #endif
2735
2736 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2737 {
2738 if (!rsk_prot)
2739 return;
2740 kfree(rsk_prot->slab_name);
2741 rsk_prot->slab_name = NULL;
2742 if (rsk_prot->slab) {
2743 kmem_cache_destroy(rsk_prot->slab);
2744 rsk_prot->slab = NULL;
2745 }
2746 }
2747
2748 static int req_prot_init(const struct proto *prot)
2749 {
2750 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2751
2752 if (!rsk_prot)
2753 return 0;
2754
2755 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2756 prot->name);
2757 if (!rsk_prot->slab_name)
2758 return -ENOMEM;
2759
2760 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2761 rsk_prot->obj_size, 0,
2762 0, NULL);
2763
2764 if (!rsk_prot->slab) {
2765 pr_crit("%s: Can't create request sock SLAB cache!\n",
2766 prot->name);
2767 return -ENOMEM;
2768 }
2769 return 0;
2770 }
2771
2772 int proto_register(struct proto *prot, int alloc_slab)
2773 {
2774 if (alloc_slab) {
2775 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2776 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2777 NULL);
2778
2779 if (prot->slab == NULL) {
2780 pr_crit("%s: Can't create sock SLAB cache!\n",
2781 prot->name);
2782 goto out;
2783 }
2784
2785 if (req_prot_init(prot))
2786 goto out_free_request_sock_slab;
2787
2788 if (prot->twsk_prot != NULL) {
2789 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2790
2791 if (prot->twsk_prot->twsk_slab_name == NULL)
2792 goto out_free_request_sock_slab;
2793
2794 prot->twsk_prot->twsk_slab =
2795 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2796 prot->twsk_prot->twsk_obj_size,
2797 0,
2798 prot->slab_flags,
2799 NULL);
2800 if (prot->twsk_prot->twsk_slab == NULL)
2801 goto out_free_timewait_sock_slab_name;
2802 }
2803 }
2804
2805 mutex_lock(&proto_list_mutex);
2806 list_add(&prot->node, &proto_list);
2807 assign_proto_idx(prot);
2808 mutex_unlock(&proto_list_mutex);
2809 return 0;
2810
2811 out_free_timewait_sock_slab_name:
2812 kfree(prot->twsk_prot->twsk_slab_name);
2813 out_free_request_sock_slab:
2814 req_prot_cleanup(prot->rsk_prot);
2815
2816 kmem_cache_destroy(prot->slab);
2817 prot->slab = NULL;
2818 out:
2819 return -ENOBUFS;
2820 }
2821 EXPORT_SYMBOL(proto_register);
2822
2823 void proto_unregister(struct proto *prot)
2824 {
2825 mutex_lock(&proto_list_mutex);
2826 release_proto_idx(prot);
2827 list_del(&prot->node);
2828 mutex_unlock(&proto_list_mutex);
2829
2830 if (prot->slab != NULL) {
2831 kmem_cache_destroy(prot->slab);
2832 prot->slab = NULL;
2833 }
2834
2835 req_prot_cleanup(prot->rsk_prot);
2836
2837 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2838 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2839 kfree(prot->twsk_prot->twsk_slab_name);
2840 prot->twsk_prot->twsk_slab = NULL;
2841 }
2842 }
2843 EXPORT_SYMBOL(proto_unregister);
2844
2845 #ifdef CONFIG_PROC_FS
2846 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2847 __acquires(proto_list_mutex)
2848 {
2849 mutex_lock(&proto_list_mutex);
2850 return seq_list_start_head(&proto_list, *pos);
2851 }
2852
2853 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2854 {
2855 return seq_list_next(v, &proto_list, pos);
2856 }
2857
2858 static void proto_seq_stop(struct seq_file *seq, void *v)
2859 __releases(proto_list_mutex)
2860 {
2861 mutex_unlock(&proto_list_mutex);
2862 }
2863
2864 static char proto_method_implemented(const void *method)
2865 {
2866 return method == NULL ? 'n' : 'y';
2867 }
2868 static long sock_prot_memory_allocated(struct proto *proto)
2869 {
2870 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2871 }
2872
2873 static char *sock_prot_memory_pressure(struct proto *proto)
2874 {
2875 return proto->memory_pressure != NULL ?
2876 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2877 }
2878
2879 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2880 {
2881
2882 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2883 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2884 proto->name,
2885 proto->obj_size,
2886 sock_prot_inuse_get(seq_file_net(seq), proto),
2887 sock_prot_memory_allocated(proto),
2888 sock_prot_memory_pressure(proto),
2889 proto->max_header,
2890 proto->slab == NULL ? "no" : "yes",
2891 module_name(proto->owner),
2892 proto_method_implemented(proto->close),
2893 proto_method_implemented(proto->connect),
2894 proto_method_implemented(proto->disconnect),
2895 proto_method_implemented(proto->accept),
2896 proto_method_implemented(proto->ioctl),
2897 proto_method_implemented(proto->init),
2898 proto_method_implemented(proto->destroy),
2899 proto_method_implemented(proto->shutdown),
2900 proto_method_implemented(proto->setsockopt),
2901 proto_method_implemented(proto->getsockopt),
2902 proto_method_implemented(proto->sendmsg),
2903 proto_method_implemented(proto->recvmsg),
2904 proto_method_implemented(proto->sendpage),
2905 proto_method_implemented(proto->bind),
2906 proto_method_implemented(proto->backlog_rcv),
2907 proto_method_implemented(proto->hash),
2908 proto_method_implemented(proto->unhash),
2909 proto_method_implemented(proto->get_port),
2910 proto_method_implemented(proto->enter_memory_pressure));
2911 }
2912
2913 static int proto_seq_show(struct seq_file *seq, void *v)
2914 {
2915 if (v == &proto_list)
2916 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2917 "protocol",
2918 "size",
2919 "sockets",
2920 "memory",
2921 "press",
2922 "maxhdr",
2923 "slab",
2924 "module",
2925 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2926 else
2927 proto_seq_printf(seq, list_entry(v, struct proto, node));
2928 return 0;
2929 }
2930
2931 static const struct seq_operations proto_seq_ops = {
2932 .start = proto_seq_start,
2933 .next = proto_seq_next,
2934 .stop = proto_seq_stop,
2935 .show = proto_seq_show,
2936 };
2937
2938 static int proto_seq_open(struct inode *inode, struct file *file)
2939 {
2940 return seq_open_net(inode, file, &proto_seq_ops,
2941 sizeof(struct seq_net_private));
2942 }
2943
2944 static const struct file_operations proto_seq_fops = {
2945 .owner = THIS_MODULE,
2946 .open = proto_seq_open,
2947 .read = seq_read,
2948 .llseek = seq_lseek,
2949 .release = seq_release_net,
2950 };
2951
2952 static __net_init int proto_init_net(struct net *net)
2953 {
2954 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
2955 return -ENOMEM;
2956
2957 return 0;
2958 }
2959
2960 static __net_exit void proto_exit_net(struct net *net)
2961 {
2962 remove_proc_entry("protocols", net->proc_net);
2963 }
2964
2965
2966 static __net_initdata struct pernet_operations proto_net_ops = {
2967 .init = proto_init_net,
2968 .exit = proto_exit_net,
2969 };
2970
2971 static int __init proto_init(void)
2972 {
2973 return register_pernet_subsys(&proto_net_ops);
2974 }
2975
2976 subsys_initcall(proto_init);
2977
2978 #endif /* PROC_FS */
Linux with added FPC-III support