projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
net: tcp_memcontrol: sanitize tcp memory accounting callbacks
[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 #include <net/sock_reuseport.h>
138
139 #include <trace/events/sock.h>
140
141 #ifdef CONFIG_INET
142 #include <net/tcp.h>
143 #endif
144
145 #include <net/busy_poll.h>
146
147 static DEFINE_MUTEX(proto_list_mutex);
148 static LIST_HEAD(proto_list);
149
150 /**
151 * sk_ns_capable - General socket capability test
152 * @sk: Socket to use a capability on or through
153 * @user_ns: The user namespace of the capability to use
154 * @cap: The capability to use
155 *
156 * Test to see if the opener of the socket had when the socket was
157 * created and the current process has the capability @cap in the user
158 * namespace @user_ns.
159 */
160 bool sk_ns_capable(const struct sock *sk,
161 struct user_namespace *user_ns, int cap)
162 {
163 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
164 ns_capable(user_ns, cap);
165 }
166 EXPORT_SYMBOL(sk_ns_capable);
167
168 /**
169 * sk_capable - Socket global capability test
170 * @sk: Socket to use a capability on or through
171 * @cap: The global capability to use
172 *
173 * Test to see if the opener of the socket had when the socket was
174 * created and the current process has the capability @cap in all user
175 * namespaces.
176 */
177 bool sk_capable(const struct sock *sk, int cap)
178 {
179 return sk_ns_capable(sk, &init_user_ns, cap);
180 }
181 EXPORT_SYMBOL(sk_capable);
182
183 /**
184 * sk_net_capable - Network namespace socket capability test
185 * @sk: Socket to use a capability on or through
186 * @cap: The capability to use
187 *
188 * Test to see if the opener of the socket had when the socket was created
189 * and the current process has the capability @cap over the network namespace
190 * the socket is a member of.
191 */
192 bool sk_net_capable(const struct sock *sk, int cap)
193 {
194 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
195 }
196 EXPORT_SYMBOL(sk_net_capable);
197
198
199 #ifdef CONFIG_MEMCG_KMEM
200 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
201 {
202 struct proto *proto;
203 int ret = 0;
204
205 mutex_lock(&proto_list_mutex);
206 list_for_each_entry(proto, &proto_list, node) {
207 if (proto->init_cgroup) {
208 ret = proto->init_cgroup(memcg, ss);
209 if (ret)
210 goto out;
211 }
212 }
213
214 mutex_unlock(&proto_list_mutex);
215 return ret;
216 out:
217 list_for_each_entry_continue_reverse(proto, &proto_list, node)
218 if (proto->destroy_cgroup)
219 proto->destroy_cgroup(memcg);
220 mutex_unlock(&proto_list_mutex);
221 return ret;
222 }
223
224 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
225 {
226 struct proto *proto;
227
228 mutex_lock(&proto_list_mutex);
229 list_for_each_entry_reverse(proto, &proto_list, node)
230 if (proto->destroy_cgroup)
231 proto->destroy_cgroup(memcg);
232 mutex_unlock(&proto_list_mutex);
233 }
234 #endif
235
236 /*
237 * Each address family might have different locking rules, so we have
238 * one slock key per address family:
239 */
240 static struct lock_class_key af_family_keys[AF_MAX];
241 static struct lock_class_key af_family_slock_keys[AF_MAX];
242
243 #if defined(CONFIG_MEMCG_KMEM)
244 struct static_key memcg_socket_limit_enabled;
245 EXPORT_SYMBOL(memcg_socket_limit_enabled);
246 #endif
247
248 /*
249 * Make lock validator output more readable. (we pre-construct these
250 * strings build-time, so that runtime initialization of socket
251 * locks is fast):
252 */
253 static const char *const af_family_key_strings[AF_MAX+1] = {
254 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
255 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
256 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
257 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
258 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
259 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
260 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
261 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
262 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
263 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
264 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
265 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
266 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
267 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
268 };
269 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
270 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
271 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
272 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
273 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
274 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
275 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
276 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
277 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
278 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
279 "slock-27" , "slock-28" , "slock-AF_CAN" ,
280 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
281 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
282 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
283 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
284 };
285 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
286 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
287 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
288 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
289 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
290 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
291 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
292 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
293 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
294 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
295 "clock-27" , "clock-28" , "clock-AF_CAN" ,
296 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
297 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
298 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
299 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
300 };
301
302 /*
303 * sk_callback_lock locking rules are per-address-family,
304 * so split the lock classes by using a per-AF key:
305 */
306 static struct lock_class_key af_callback_keys[AF_MAX];
307
308 /* Take into consideration the size of the struct sk_buff overhead in the
309 * determination of these values, since that is non-constant across
310 * platforms. This makes socket queueing behavior and performance
311 * not depend upon such differences.
312 */
313 #define _SK_MEM_PACKETS 256
314 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
315 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
316 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
317
318 /* Run time adjustable parameters. */
319 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
320 EXPORT_SYMBOL(sysctl_wmem_max);
321 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
322 EXPORT_SYMBOL(sysctl_rmem_max);
323 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
324 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
325
326 /* Maximal space eaten by iovec or ancillary data plus some space */
327 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
328 EXPORT_SYMBOL(sysctl_optmem_max);
329
330 int sysctl_tstamp_allow_data __read_mostly = 1;
331
332 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
333 EXPORT_SYMBOL_GPL(memalloc_socks);
334
335 /**
336 * sk_set_memalloc - sets %SOCK_MEMALLOC
337 * @sk: socket to set it on
338 *
339 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
340 * It's the responsibility of the admin to adjust min_free_kbytes
341 * to meet the requirements
342 */
343 void sk_set_memalloc(struct sock *sk)
344 {
345 sock_set_flag(sk, SOCK_MEMALLOC);
346 sk->sk_allocation |= __GFP_MEMALLOC;
347 static_key_slow_inc(&memalloc_socks);
348 }
349 EXPORT_SYMBOL_GPL(sk_set_memalloc);
350
351 void sk_clear_memalloc(struct sock *sk)
352 {
353 sock_reset_flag(sk, SOCK_MEMALLOC);
354 sk->sk_allocation &= ~__GFP_MEMALLOC;
355 static_key_slow_dec(&memalloc_socks);
356
357 /*
358 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
359 * progress of swapping. SOCK_MEMALLOC may be cleared while
360 * it has rmem allocations due to the last swapfile being deactivated
361 * but there is a risk that the socket is unusable due to exceeding
362 * the rmem limits. Reclaim the reserves and obey rmem limits again.
363 */
364 sk_mem_reclaim(sk);
365 }
366 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
367
368 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
369 {
370 int ret;
371 unsigned long pflags = current->flags;
372
373 /* these should have been dropped before queueing */
374 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
375
376 current->flags |= PF_MEMALLOC;
377 ret = sk->sk_backlog_rcv(sk, skb);
378 tsk_restore_flags(current, pflags, PF_MEMALLOC);
379
380 return ret;
381 }
382 EXPORT_SYMBOL(__sk_backlog_rcv);
383
384 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
385 {
386 struct timeval tv;
387
388 if (optlen < sizeof(tv))
389 return -EINVAL;
390 if (copy_from_user(&tv, optval, sizeof(tv)))
391 return -EFAULT;
392 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
393 return -EDOM;
394
395 if (tv.tv_sec < 0) {
396 static int warned __read_mostly;
397
398 *timeo_p = 0;
399 if (warned < 10 && net_ratelimit()) {
400 warned++;
401 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
402 __func__, current->comm, task_pid_nr(current));
403 }
404 return 0;
405 }
406 *timeo_p = MAX_SCHEDULE_TIMEOUT;
407 if (tv.tv_sec == 0 && tv.tv_usec == 0)
408 return 0;
409 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
410 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
411 return 0;
412 }
413
414 static void sock_warn_obsolete_bsdism(const char *name)
415 {
416 static int warned;
417 static char warncomm[TASK_COMM_LEN];
418 if (strcmp(warncomm, current->comm) && warned < 5) {
419 strcpy(warncomm, current->comm);
420 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
421 warncomm, name);
422 warned++;
423 }
424 }
425
426 static bool sock_needs_netstamp(const struct sock *sk)
427 {
428 switch (sk->sk_family) {
429 case AF_UNSPEC:
430 case AF_UNIX:
431 return false;
432 default:
433 return true;
434 }
435 }
436
437 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
438 {
439 if (sk->sk_flags & flags) {
440 sk->sk_flags &= ~flags;
441 if (sock_needs_netstamp(sk) &&
442 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
443 net_disable_timestamp();
444 }
445 }
446
447
448 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
449 {
450 int err;
451 unsigned long flags;
452 struct sk_buff_head *list = &sk->sk_receive_queue;
453
454 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
455 atomic_inc(&sk->sk_drops);
456 trace_sock_rcvqueue_full(sk, skb);
457 return -ENOMEM;
458 }
459
460 err = sk_filter(sk, skb);
461 if (err)
462 return err;
463
464 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
465 atomic_inc(&sk->sk_drops);
466 return -ENOBUFS;
467 }
468
469 skb->dev = NULL;
470 skb_set_owner_r(skb, sk);
471
472 /* we escape from rcu protected region, make sure we dont leak
473 * a norefcounted dst
474 */
475 skb_dst_force(skb);
476
477 spin_lock_irqsave(&list->lock, flags);
478 sock_skb_set_dropcount(sk, skb);
479 __skb_queue_tail(list, skb);
480 spin_unlock_irqrestore(&list->lock, flags);
481
482 if (!sock_flag(sk, SOCK_DEAD))
483 sk->sk_data_ready(sk);
484 return 0;
485 }
486 EXPORT_SYMBOL(sock_queue_rcv_skb);
487
488 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
489 {
490 int rc = NET_RX_SUCCESS;
491
492 if (sk_filter(sk, skb))
493 goto discard_and_relse;
494
495 skb->dev = NULL;
496
497 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
498 atomic_inc(&sk->sk_drops);
499 goto discard_and_relse;
500 }
501 if (nested)
502 bh_lock_sock_nested(sk);
503 else
504 bh_lock_sock(sk);
505 if (!sock_owned_by_user(sk)) {
506 /*
507 * trylock + unlock semantics:
508 */
509 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
510
511 rc = sk_backlog_rcv(sk, skb);
512
513 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
514 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
515 bh_unlock_sock(sk);
516 atomic_inc(&sk->sk_drops);
517 goto discard_and_relse;
518 }
519
520 bh_unlock_sock(sk);
521 out:
522 sock_put(sk);
523 return rc;
524 discard_and_relse:
525 kfree_skb(skb);
526 goto out;
527 }
528 EXPORT_SYMBOL(sk_receive_skb);
529
530 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
531 {
532 struct dst_entry *dst = __sk_dst_get(sk);
533
534 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
535 sk_tx_queue_clear(sk);
536 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
537 dst_release(dst);
538 return NULL;
539 }
540
541 return dst;
542 }
543 EXPORT_SYMBOL(__sk_dst_check);
544
545 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
546 {
547 struct dst_entry *dst = sk_dst_get(sk);
548
549 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
550 sk_dst_reset(sk);
551 dst_release(dst);
552 return NULL;
553 }
554
555 return dst;
556 }
557 EXPORT_SYMBOL(sk_dst_check);
558
559 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
560 int optlen)
561 {
562 int ret = -ENOPROTOOPT;
563 #ifdef CONFIG_NETDEVICES
564 struct net *net = sock_net(sk);
565 char devname[IFNAMSIZ];
566 int index;
567
568 /* Sorry... */
569 ret = -EPERM;
570 if (!ns_capable(net->user_ns, CAP_NET_RAW))
571 goto out;
572
573 ret = -EINVAL;
574 if (optlen < 0)
575 goto out;
576
577 /* Bind this socket to a particular device like "eth0",
578 * as specified in the passed interface name. If the
579 * name is "" or the option length is zero the socket
580 * is not bound.
581 */
582 if (optlen > IFNAMSIZ - 1)
583 optlen = IFNAMSIZ - 1;
584 memset(devname, 0, sizeof(devname));
585
586 ret = -EFAULT;
587 if (copy_from_user(devname, optval, optlen))
588 goto out;
589
590 index = 0;
591 if (devname[0] != '\0') {
592 struct net_device *dev;
593
594 rcu_read_lock();
595 dev = dev_get_by_name_rcu(net, devname);
596 if (dev)
597 index = dev->ifindex;
598 rcu_read_unlock();
599 ret = -ENODEV;
600 if (!dev)
601 goto out;
602 }
603
604 lock_sock(sk);
605 sk->sk_bound_dev_if = index;
606 sk_dst_reset(sk);
607 release_sock(sk);
608
609 ret = 0;
610
611 out:
612 #endif
613
614 return ret;
615 }
616
617 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
618 int __user *optlen, int len)
619 {
620 int ret = -ENOPROTOOPT;
621 #ifdef CONFIG_NETDEVICES
622 struct net *net = sock_net(sk);
623 char devname[IFNAMSIZ];
624
625 if (sk->sk_bound_dev_if == 0) {
626 len = 0;
627 goto zero;
628 }
629
630 ret = -EINVAL;
631 if (len < IFNAMSIZ)
632 goto out;
633
634 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
635 if (ret)
636 goto out;
637
638 len = strlen(devname) + 1;
639
640 ret = -EFAULT;
641 if (copy_to_user(optval, devname, len))
642 goto out;
643
644 zero:
645 ret = -EFAULT;
646 if (put_user(len, optlen))
647 goto out;
648
649 ret = 0;
650
651 out:
652 #endif
653
654 return ret;
655 }
656
657 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
658 {
659 if (valbool)
660 sock_set_flag(sk, bit);
661 else
662 sock_reset_flag(sk, bit);
663 }
664
665 bool sk_mc_loop(struct sock *sk)
666 {
667 if (dev_recursion_level())
668 return false;
669 if (!sk)
670 return true;
671 switch (sk->sk_family) {
672 case AF_INET:
673 return inet_sk(sk)->mc_loop;
674 #if IS_ENABLED(CONFIG_IPV6)
675 case AF_INET6:
676 return inet6_sk(sk)->mc_loop;
677 #endif
678 }
679 WARN_ON(1);
680 return true;
681 }
682 EXPORT_SYMBOL(sk_mc_loop);
683
684 /*
685 * This is meant for all protocols to use and covers goings on
686 * at the socket level. Everything here is generic.
687 */
688
689 int sock_setsockopt(struct socket *sock, int level, int optname,
690 char __user *optval, unsigned int optlen)
691 {
692 struct sock *sk = sock->sk;
693 int val;
694 int valbool;
695 struct linger ling;
696 int ret = 0;
697
698 /*
699 * Options without arguments
700 */
701
702 if (optname == SO_BINDTODEVICE)
703 return sock_setbindtodevice(sk, optval, optlen);
704
705 if (optlen < sizeof(int))
706 return -EINVAL;
707
708 if (get_user(val, (int __user *)optval))
709 return -EFAULT;
710
711 valbool = val ? 1 : 0;
712
713 lock_sock(sk);
714
715 switch (optname) {
716 case SO_DEBUG:
717 if (val && !capable(CAP_NET_ADMIN))
718 ret = -EACCES;
719 else
720 sock_valbool_flag(sk, SOCK_DBG, valbool);
721 break;
722 case SO_REUSEADDR:
723 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
724 break;
725 case SO_REUSEPORT:
726 sk->sk_reuseport = valbool;
727 break;
728 case SO_TYPE:
729 case SO_PROTOCOL:
730 case SO_DOMAIN:
731 case SO_ERROR:
732 ret = -ENOPROTOOPT;
733 break;
734 case SO_DONTROUTE:
735 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
736 break;
737 case SO_BROADCAST:
738 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
739 break;
740 case SO_SNDBUF:
741 /* Don't error on this BSD doesn't and if you think
742 * about it this is right. Otherwise apps have to
743 * play 'guess the biggest size' games. RCVBUF/SNDBUF
744 * are treated in BSD as hints
745 */
746 val = min_t(u32, val, sysctl_wmem_max);
747 set_sndbuf:
748 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
749 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
750 /* Wake up sending tasks if we upped the value. */
751 sk->sk_write_space(sk);
752 break;
753
754 case SO_SNDBUFFORCE:
755 if (!capable(CAP_NET_ADMIN)) {
756 ret = -EPERM;
757 break;
758 }
759 goto set_sndbuf;
760
761 case SO_RCVBUF:
762 /* Don't error on this BSD doesn't and if you think
763 * about it this is right. Otherwise apps have to
764 * play 'guess the biggest size' games. RCVBUF/SNDBUF
765 * are treated in BSD as hints
766 */
767 val = min_t(u32, val, sysctl_rmem_max);
768 set_rcvbuf:
769 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
770 /*
771 * We double it on the way in to account for
772 * "struct sk_buff" etc. overhead. Applications
773 * assume that the SO_RCVBUF setting they make will
774 * allow that much actual data to be received on that
775 * socket.
776 *
777 * Applications are unaware that "struct sk_buff" and
778 * other overheads allocate from the receive buffer
779 * during socket buffer allocation.
780 *
781 * And after considering the possible alternatives,
782 * returning the value we actually used in getsockopt
783 * is the most desirable behavior.
784 */
785 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
786 break;
787
788 case SO_RCVBUFFORCE:
789 if (!capable(CAP_NET_ADMIN)) {
790 ret = -EPERM;
791 break;
792 }
793 goto set_rcvbuf;
794
795 case SO_KEEPALIVE:
796 #ifdef CONFIG_INET
797 if (sk->sk_protocol == IPPROTO_TCP &&
798 sk->sk_type == SOCK_STREAM)
799 tcp_set_keepalive(sk, valbool);
800 #endif
801 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
802 break;
803
804 case SO_OOBINLINE:
805 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
806 break;
807
808 case SO_NO_CHECK:
809 sk->sk_no_check_tx = valbool;
810 break;
811
812 case SO_PRIORITY:
813 if ((val >= 0 && val <= 6) ||
814 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
815 sk->sk_priority = val;
816 else
817 ret = -EPERM;
818 break;
819
820 case SO_LINGER:
821 if (optlen < sizeof(ling)) {
822 ret = -EINVAL; /* 1003.1g */
823 break;
824 }
825 if (copy_from_user(&ling, optval, sizeof(ling))) {
826 ret = -EFAULT;
827 break;
828 }
829 if (!ling.l_onoff)
830 sock_reset_flag(sk, SOCK_LINGER);
831 else {
832 #if (BITS_PER_LONG == 32)
833 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
834 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
835 else
836 #endif
837 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
838 sock_set_flag(sk, SOCK_LINGER);
839 }
840 break;
841
842 case SO_BSDCOMPAT:
843 sock_warn_obsolete_bsdism("setsockopt");
844 break;
845
846 case SO_PASSCRED:
847 if (valbool)
848 set_bit(SOCK_PASSCRED, &sock->flags);
849 else
850 clear_bit(SOCK_PASSCRED, &sock->flags);
851 break;
852
853 case SO_TIMESTAMP:
854 case SO_TIMESTAMPNS:
855 if (valbool) {
856 if (optname == SO_TIMESTAMP)
857 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
858 else
859 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
860 sock_set_flag(sk, SOCK_RCVTSTAMP);
861 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
862 } else {
863 sock_reset_flag(sk, SOCK_RCVTSTAMP);
864 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
865 }
866 break;
867
868 case SO_TIMESTAMPING:
869 if (val & ~SOF_TIMESTAMPING_MASK) {
870 ret = -EINVAL;
871 break;
872 }
873
874 if (val & SOF_TIMESTAMPING_OPT_ID &&
875 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
876 if (sk->sk_protocol == IPPROTO_TCP &&
877 sk->sk_type == SOCK_STREAM) {
878 if (sk->sk_state != TCP_ESTABLISHED) {
879 ret = -EINVAL;
880 break;
881 }
882 sk->sk_tskey = tcp_sk(sk)->snd_una;
883 } else {
884 sk->sk_tskey = 0;
885 }
886 }
887 sk->sk_tsflags = val;
888 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
889 sock_enable_timestamp(sk,
890 SOCK_TIMESTAMPING_RX_SOFTWARE);
891 else
892 sock_disable_timestamp(sk,
893 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
894 break;
895
896 case SO_RCVLOWAT:
897 if (val < 0)
898 val = INT_MAX;
899 sk->sk_rcvlowat = val ? : 1;
900 break;
901
902 case SO_RCVTIMEO:
903 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
904 break;
905
906 case SO_SNDTIMEO:
907 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
908 break;
909
910 case SO_ATTACH_FILTER:
911 ret = -EINVAL;
912 if (optlen == sizeof(struct sock_fprog)) {
913 struct sock_fprog fprog;
914
915 ret = -EFAULT;
916 if (copy_from_user(&fprog, optval, sizeof(fprog)))
917 break;
918
919 ret = sk_attach_filter(&fprog, sk);
920 }
921 break;
922
923 case SO_ATTACH_BPF:
924 ret = -EINVAL;
925 if (optlen == sizeof(u32)) {
926 u32 ufd;
927
928 ret = -EFAULT;
929 if (copy_from_user(&ufd, optval, sizeof(ufd)))
930 break;
931
932 ret = sk_attach_bpf(ufd, sk);
933 }
934 break;
935
936 case SO_ATTACH_REUSEPORT_CBPF:
937 ret = -EINVAL;
938 if (optlen == sizeof(struct sock_fprog)) {
939 struct sock_fprog fprog;
940
941 ret = -EFAULT;
942 if (copy_from_user(&fprog, optval, sizeof(fprog)))
943 break;
944
945 ret = sk_reuseport_attach_filter(&fprog, sk);
946 }
947 break;
948
949 case SO_ATTACH_REUSEPORT_EBPF:
950 ret = -EINVAL;
951 if (optlen == sizeof(u32)) {
952 u32 ufd;
953
954 ret = -EFAULT;
955 if (copy_from_user(&ufd, optval, sizeof(ufd)))
956 break;
957
958 ret = sk_reuseport_attach_bpf(ufd, sk);
959 }
960 break;
961
962 case SO_DETACH_FILTER:
963 ret = sk_detach_filter(sk);
964 break;
965
966 case SO_LOCK_FILTER:
967 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
968 ret = -EPERM;
969 else
970 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
971 break;
972
973 case SO_PASSSEC:
974 if (valbool)
975 set_bit(SOCK_PASSSEC, &sock->flags);
976 else
977 clear_bit(SOCK_PASSSEC, &sock->flags);
978 break;
979 case SO_MARK:
980 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
981 ret = -EPERM;
982 else
983 sk->sk_mark = val;
984 break;
985
986 case SO_RXQ_OVFL:
987 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
988 break;
989
990 case SO_WIFI_STATUS:
991 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
992 break;
993
994 case SO_PEEK_OFF:
995 if (sock->ops->set_peek_off)
996 ret = sock->ops->set_peek_off(sk, val);
997 else
998 ret = -EOPNOTSUPP;
999 break;
1000
1001 case SO_NOFCS:
1002 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1003 break;
1004
1005 case SO_SELECT_ERR_QUEUE:
1006 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1007 break;
1008
1009 #ifdef CONFIG_NET_RX_BUSY_POLL
1010 case SO_BUSY_POLL:
1011 /* allow unprivileged users to decrease the value */
1012 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1013 ret = -EPERM;
1014 else {
1015 if (val < 0)
1016 ret = -EINVAL;
1017 else
1018 sk->sk_ll_usec = val;
1019 }
1020 break;
1021 #endif
1022
1023 case SO_MAX_PACING_RATE:
1024 sk->sk_max_pacing_rate = val;
1025 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1026 sk->sk_max_pacing_rate);
1027 break;
1028
1029 case SO_INCOMING_CPU:
1030 sk->sk_incoming_cpu = val;
1031 break;
1032
1033 default:
1034 ret = -ENOPROTOOPT;
1035 break;
1036 }
1037 release_sock(sk);
1038 return ret;
1039 }
1040 EXPORT_SYMBOL(sock_setsockopt);
1041
1042
1043 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1044 struct ucred *ucred)
1045 {
1046 ucred->pid = pid_vnr(pid);
1047 ucred->uid = ucred->gid = -1;
1048 if (cred) {
1049 struct user_namespace *current_ns = current_user_ns();
1050
1051 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1052 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1053 }
1054 }
1055
1056 int sock_getsockopt(struct socket *sock, int level, int optname,
1057 char __user *optval, int __user *optlen)
1058 {
1059 struct sock *sk = sock->sk;
1060
1061 union {
1062 int val;
1063 struct linger ling;
1064 struct timeval tm;
1065 } v;
1066
1067 int lv = sizeof(int);
1068 int len;
1069
1070 if (get_user(len, optlen))
1071 return -EFAULT;
1072 if (len < 0)
1073 return -EINVAL;
1074
1075 memset(&v, 0, sizeof(v));
1076
1077 switch (optname) {
1078 case SO_DEBUG:
1079 v.val = sock_flag(sk, SOCK_DBG);
1080 break;
1081
1082 case SO_DONTROUTE:
1083 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1084 break;
1085
1086 case SO_BROADCAST:
1087 v.val = sock_flag(sk, SOCK_BROADCAST);
1088 break;
1089
1090 case SO_SNDBUF:
1091 v.val = sk->sk_sndbuf;
1092 break;
1093
1094 case SO_RCVBUF:
1095 v.val = sk->sk_rcvbuf;
1096 break;
1097
1098 case SO_REUSEADDR:
1099 v.val = sk->sk_reuse;
1100 break;
1101
1102 case SO_REUSEPORT:
1103 v.val = sk->sk_reuseport;
1104 break;
1105
1106 case SO_KEEPALIVE:
1107 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1108 break;
1109
1110 case SO_TYPE:
1111 v.val = sk->sk_type;
1112 break;
1113
1114 case SO_PROTOCOL:
1115 v.val = sk->sk_protocol;
1116 break;
1117
1118 case SO_DOMAIN:
1119 v.val = sk->sk_family;
1120 break;
1121
1122 case SO_ERROR:
1123 v.val = -sock_error(sk);
1124 if (v.val == 0)
1125 v.val = xchg(&sk->sk_err_soft, 0);
1126 break;
1127
1128 case SO_OOBINLINE:
1129 v.val = sock_flag(sk, SOCK_URGINLINE);
1130 break;
1131
1132 case SO_NO_CHECK:
1133 v.val = sk->sk_no_check_tx;
1134 break;
1135
1136 case SO_PRIORITY:
1137 v.val = sk->sk_priority;
1138 break;
1139
1140 case SO_LINGER:
1141 lv = sizeof(v.ling);
1142 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1143 v.ling.l_linger = sk->sk_lingertime / HZ;
1144 break;
1145
1146 case SO_BSDCOMPAT:
1147 sock_warn_obsolete_bsdism("getsockopt");
1148 break;
1149
1150 case SO_TIMESTAMP:
1151 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1152 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1153 break;
1154
1155 case SO_TIMESTAMPNS:
1156 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1157 break;
1158
1159 case SO_TIMESTAMPING:
1160 v.val = sk->sk_tsflags;
1161 break;
1162
1163 case SO_RCVTIMEO:
1164 lv = sizeof(struct timeval);
1165 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1166 v.tm.tv_sec = 0;
1167 v.tm.tv_usec = 0;
1168 } else {
1169 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1170 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1171 }
1172 break;
1173
1174 case SO_SNDTIMEO:
1175 lv = sizeof(struct timeval);
1176 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1177 v.tm.tv_sec = 0;
1178 v.tm.tv_usec = 0;
1179 } else {
1180 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1181 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1182 }
1183 break;
1184
1185 case SO_RCVLOWAT:
1186 v.val = sk->sk_rcvlowat;
1187 break;
1188
1189 case SO_SNDLOWAT:
1190 v.val = 1;
1191 break;
1192
1193 case SO_PASSCRED:
1194 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1195 break;
1196
1197 case SO_PEERCRED:
1198 {
1199 struct ucred peercred;
1200 if (len > sizeof(peercred))
1201 len = sizeof(peercred);
1202 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1203 if (copy_to_user(optval, &peercred, len))
1204 return -EFAULT;
1205 goto lenout;
1206 }
1207
1208 case SO_PEERNAME:
1209 {
1210 char address[128];
1211
1212 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1213 return -ENOTCONN;
1214 if (lv < len)
1215 return -EINVAL;
1216 if (copy_to_user(optval, address, len))
1217 return -EFAULT;
1218 goto lenout;
1219 }
1220
1221 /* Dubious BSD thing... Probably nobody even uses it, but
1222 * the UNIX standard wants it for whatever reason... -DaveM
1223 */
1224 case SO_ACCEPTCONN:
1225 v.val = sk->sk_state == TCP_LISTEN;
1226 break;
1227
1228 case SO_PASSSEC:
1229 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1230 break;
1231
1232 case SO_PEERSEC:
1233 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1234
1235 case SO_MARK:
1236 v.val = sk->sk_mark;
1237 break;
1238
1239 case SO_RXQ_OVFL:
1240 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1241 break;
1242
1243 case SO_WIFI_STATUS:
1244 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1245 break;
1246
1247 case SO_PEEK_OFF:
1248 if (!sock->ops->set_peek_off)
1249 return -EOPNOTSUPP;
1250
1251 v.val = sk->sk_peek_off;
1252 break;
1253 case SO_NOFCS:
1254 v.val = sock_flag(sk, SOCK_NOFCS);
1255 break;
1256
1257 case SO_BINDTODEVICE:
1258 return sock_getbindtodevice(sk, optval, optlen, len);
1259
1260 case SO_GET_FILTER:
1261 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1262 if (len < 0)
1263 return len;
1264
1265 goto lenout;
1266
1267 case SO_LOCK_FILTER:
1268 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1269 break;
1270
1271 case SO_BPF_EXTENSIONS:
1272 v.val = bpf_tell_extensions();
1273 break;
1274
1275 case SO_SELECT_ERR_QUEUE:
1276 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1277 break;
1278
1279 #ifdef CONFIG_NET_RX_BUSY_POLL
1280 case SO_BUSY_POLL:
1281 v.val = sk->sk_ll_usec;
1282 break;
1283 #endif
1284
1285 case SO_MAX_PACING_RATE:
1286 v.val = sk->sk_max_pacing_rate;
1287 break;
1288
1289 case SO_INCOMING_CPU:
1290 v.val = sk->sk_incoming_cpu;
1291 break;
1292
1293 default:
1294 /* We implement the SO_SNDLOWAT etc to not be settable
1295 * (1003.1g 7).
1296 */
1297 return -ENOPROTOOPT;
1298 }
1299
1300 if (len > lv)
1301 len = lv;
1302 if (copy_to_user(optval, &v, len))
1303 return -EFAULT;
1304 lenout:
1305 if (put_user(len, optlen))
1306 return -EFAULT;
1307 return 0;
1308 }
1309
1310 /*
1311 * Initialize an sk_lock.
1312 *
1313 * (We also register the sk_lock with the lock validator.)
1314 */
1315 static inline void sock_lock_init(struct sock *sk)
1316 {
1317 sock_lock_init_class_and_name(sk,
1318 af_family_slock_key_strings[sk->sk_family],
1319 af_family_slock_keys + sk->sk_family,
1320 af_family_key_strings[sk->sk_family],
1321 af_family_keys + sk->sk_family);
1322 }
1323
1324 /*
1325 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1326 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1327 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1328 */
1329 static void sock_copy(struct sock *nsk, const struct sock *osk)
1330 {
1331 #ifdef CONFIG_SECURITY_NETWORK
1332 void *sptr = nsk->sk_security;
1333 #endif
1334 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1335
1336 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1337 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1338
1339 #ifdef CONFIG_SECURITY_NETWORK
1340 nsk->sk_security = sptr;
1341 security_sk_clone(osk, nsk);
1342 #endif
1343 }
1344
1345 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1346 {
1347 unsigned long nulls1, nulls2;
1348
1349 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1350 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1351 if (nulls1 > nulls2)
1352 swap(nulls1, nulls2);
1353
1354 if (nulls1 != 0)
1355 memset((char *)sk, 0, nulls1);
1356 memset((char *)sk + nulls1 + sizeof(void *), 0,
1357 nulls2 - nulls1 - sizeof(void *));
1358 memset((char *)sk + nulls2 + sizeof(void *), 0,
1359 size - nulls2 - sizeof(void *));
1360 }
1361 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1362
1363 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1364 int family)
1365 {
1366 struct sock *sk;
1367 struct kmem_cache *slab;
1368
1369 slab = prot->slab;
1370 if (slab != NULL) {
1371 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1372 if (!sk)
1373 return sk;
1374 if (priority & __GFP_ZERO) {
1375 if (prot->clear_sk)
1376 prot->clear_sk(sk, prot->obj_size);
1377 else
1378 sk_prot_clear_nulls(sk, prot->obj_size);
1379 }
1380 } else
1381 sk = kmalloc(prot->obj_size, priority);
1382
1383 if (sk != NULL) {
1384 kmemcheck_annotate_bitfield(sk, flags);
1385
1386 if (security_sk_alloc(sk, family, priority))
1387 goto out_free;
1388
1389 if (!try_module_get(prot->owner))
1390 goto out_free_sec;
1391 sk_tx_queue_clear(sk);
1392 cgroup_sk_alloc(&sk->sk_cgrp_data);
1393 }
1394
1395 return sk;
1396
1397 out_free_sec:
1398 security_sk_free(sk);
1399 out_free:
1400 if (slab != NULL)
1401 kmem_cache_free(slab, sk);
1402 else
1403 kfree(sk);
1404 return NULL;
1405 }
1406
1407 static void sk_prot_free(struct proto *prot, struct sock *sk)
1408 {
1409 struct kmem_cache *slab;
1410 struct module *owner;
1411
1412 owner = prot->owner;
1413 slab = prot->slab;
1414
1415 cgroup_sk_free(&sk->sk_cgrp_data);
1416 security_sk_free(sk);
1417 if (slab != NULL)
1418 kmem_cache_free(slab, sk);
1419 else
1420 kfree(sk);
1421 module_put(owner);
1422 }
1423
1424 /**
1425 * sk_alloc - All socket objects are allocated here
1426 * @net: the applicable net namespace
1427 * @family: protocol family
1428 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1429 * @prot: struct proto associated with this new sock instance
1430 * @kern: is this to be a kernel socket?
1431 */
1432 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1433 struct proto *prot, int kern)
1434 {
1435 struct sock *sk;
1436
1437 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1438 if (sk) {
1439 sk->sk_family = family;
1440 /*
1441 * See comment in struct sock definition to understand
1442 * why we need sk_prot_creator -acme
1443 */
1444 sk->sk_prot = sk->sk_prot_creator = prot;
1445 sock_lock_init(sk);
1446 sk->sk_net_refcnt = kern ? 0 : 1;
1447 if (likely(sk->sk_net_refcnt))
1448 get_net(net);
1449 sock_net_set(sk, net);
1450 atomic_set(&sk->sk_wmem_alloc, 1);
1451
1452 sock_update_classid(&sk->sk_cgrp_data);
1453 sock_update_netprioidx(&sk->sk_cgrp_data);
1454 }
1455
1456 return sk;
1457 }
1458 EXPORT_SYMBOL(sk_alloc);
1459
1460 void sk_destruct(struct sock *sk)
1461 {
1462 struct sk_filter *filter;
1463
1464 if (sk->sk_destruct)
1465 sk->sk_destruct(sk);
1466
1467 filter = rcu_dereference_check(sk->sk_filter,
1468 atomic_read(&sk->sk_wmem_alloc) == 0);
1469 if (filter) {
1470 sk_filter_uncharge(sk, filter);
1471 RCU_INIT_POINTER(sk->sk_filter, NULL);
1472 }
1473 if (rcu_access_pointer(sk->sk_reuseport_cb))
1474 reuseport_detach_sock(sk);
1475
1476 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1477
1478 if (atomic_read(&sk->sk_omem_alloc))
1479 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1480 __func__, atomic_read(&sk->sk_omem_alloc));
1481
1482 if (sk->sk_peer_cred)
1483 put_cred(sk->sk_peer_cred);
1484 put_pid(sk->sk_peer_pid);
1485 if (likely(sk->sk_net_refcnt))
1486 put_net(sock_net(sk));
1487 sk_prot_free(sk->sk_prot_creator, sk);
1488 }
1489
1490 static void __sk_free(struct sock *sk)
1491 {
1492 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1493 sock_diag_broadcast_destroy(sk);
1494 else
1495 sk_destruct(sk);
1496 }
1497
1498 void sk_free(struct sock *sk)
1499 {
1500 /*
1501 * We subtract one from sk_wmem_alloc and can know if
1502 * some packets are still in some tx queue.
1503 * If not null, sock_wfree() will call __sk_free(sk) later
1504 */
1505 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1506 __sk_free(sk);
1507 }
1508 EXPORT_SYMBOL(sk_free);
1509
1510 /**
1511 * sk_clone_lock - clone a socket, and lock its clone
1512 * @sk: the socket to clone
1513 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1514 *
1515 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1516 */
1517 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1518 {
1519 struct sock *newsk;
1520 bool is_charged = true;
1521
1522 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1523 if (newsk != NULL) {
1524 struct sk_filter *filter;
1525
1526 sock_copy(newsk, sk);
1527
1528 /* SANITY */
1529 if (likely(newsk->sk_net_refcnt))
1530 get_net(sock_net(newsk));
1531 sk_node_init(&newsk->sk_node);
1532 sock_lock_init(newsk);
1533 bh_lock_sock(newsk);
1534 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1535 newsk->sk_backlog.len = 0;
1536
1537 atomic_set(&newsk->sk_rmem_alloc, 0);
1538 /*
1539 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1540 */
1541 atomic_set(&newsk->sk_wmem_alloc, 1);
1542 atomic_set(&newsk->sk_omem_alloc, 0);
1543 skb_queue_head_init(&newsk->sk_receive_queue);
1544 skb_queue_head_init(&newsk->sk_write_queue);
1545
1546 rwlock_init(&newsk->sk_callback_lock);
1547 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1548 af_callback_keys + newsk->sk_family,
1549 af_family_clock_key_strings[newsk->sk_family]);
1550
1551 newsk->sk_dst_cache = NULL;
1552 newsk->sk_wmem_queued = 0;
1553 newsk->sk_forward_alloc = 0;
1554 newsk->sk_send_head = NULL;
1555 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1556
1557 sock_reset_flag(newsk, SOCK_DONE);
1558 skb_queue_head_init(&newsk->sk_error_queue);
1559
1560 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1561 if (filter != NULL)
1562 /* though it's an empty new sock, the charging may fail
1563 * if sysctl_optmem_max was changed between creation of
1564 * original socket and cloning
1565 */
1566 is_charged = sk_filter_charge(newsk, filter);
1567
1568 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1569 /* It is still raw copy of parent, so invalidate
1570 * destructor and make plain sk_free() */
1571 newsk->sk_destruct = NULL;
1572 bh_unlock_sock(newsk);
1573 sk_free(newsk);
1574 newsk = NULL;
1575 goto out;
1576 }
1577
1578 newsk->sk_err = 0;
1579 newsk->sk_priority = 0;
1580 newsk->sk_incoming_cpu = raw_smp_processor_id();
1581 atomic64_set(&newsk->sk_cookie, 0);
1582 /*
1583 * Before updating sk_refcnt, we must commit prior changes to memory
1584 * (Documentation/RCU/rculist_nulls.txt for details)
1585 */
1586 smp_wmb();
1587 atomic_set(&newsk->sk_refcnt, 2);
1588
1589 /*
1590 * Increment the counter in the same struct proto as the master
1591 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1592 * is the same as sk->sk_prot->socks, as this field was copied
1593 * with memcpy).
1594 *
1595 * This _changes_ the previous behaviour, where
1596 * tcp_create_openreq_child always was incrementing the
1597 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1598 * to be taken into account in all callers. -acme
1599 */
1600 sk_refcnt_debug_inc(newsk);
1601 sk_set_socket(newsk, NULL);
1602 newsk->sk_wq = NULL;
1603
1604 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1605 sock_update_memcg(newsk);
1606
1607 if (newsk->sk_prot->sockets_allocated)
1608 sk_sockets_allocated_inc(newsk);
1609
1610 if (sock_needs_netstamp(sk) &&
1611 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1612 net_enable_timestamp();
1613 }
1614 out:
1615 return newsk;
1616 }
1617 EXPORT_SYMBOL_GPL(sk_clone_lock);
1618
1619 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1620 {
1621 u32 max_segs = 1;
1622
1623 sk_dst_set(sk, dst);
1624 sk->sk_route_caps = dst->dev->features;
1625 if (sk->sk_route_caps & NETIF_F_GSO)
1626 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1627 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1628 if (sk_can_gso(sk)) {
1629 if (dst->header_len) {
1630 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1631 } else {
1632 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1633 sk->sk_gso_max_size = dst->dev->gso_max_size;
1634 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1635 }
1636 }
1637 sk->sk_gso_max_segs = max_segs;
1638 }
1639 EXPORT_SYMBOL_GPL(sk_setup_caps);
1640
1641 /*
1642 * Simple resource managers for sockets.
1643 */
1644
1645
1646 /*
1647 * Write buffer destructor automatically called from kfree_skb.
1648 */
1649 void sock_wfree(struct sk_buff *skb)
1650 {
1651 struct sock *sk = skb->sk;
1652 unsigned int len = skb->truesize;
1653
1654 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1655 /*
1656 * Keep a reference on sk_wmem_alloc, this will be released
1657 * after sk_write_space() call
1658 */
1659 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1660 sk->sk_write_space(sk);
1661 len = 1;
1662 }
1663 /*
1664 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1665 * could not do because of in-flight packets
1666 */
1667 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1668 __sk_free(sk);
1669 }
1670 EXPORT_SYMBOL(sock_wfree);
1671
1672 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1673 {
1674 skb_orphan(skb);
1675 skb->sk = sk;
1676 #ifdef CONFIG_INET
1677 if (unlikely(!sk_fullsock(sk))) {
1678 skb->destructor = sock_edemux;
1679 sock_hold(sk);
1680 return;
1681 }
1682 #endif
1683 skb->destructor = sock_wfree;
1684 skb_set_hash_from_sk(skb, sk);
1685 /*
1686 * We used to take a refcount on sk, but following operation
1687 * is enough to guarantee sk_free() wont free this sock until
1688 * all in-flight packets are completed
1689 */
1690 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1691 }
1692 EXPORT_SYMBOL(skb_set_owner_w);
1693
1694 void skb_orphan_partial(struct sk_buff *skb)
1695 {
1696 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1697 * so we do not completely orphan skb, but transfert all
1698 * accounted bytes but one, to avoid unexpected reorders.
1699 */
1700 if (skb->destructor == sock_wfree
1701 #ifdef CONFIG_INET
1702 || skb->destructor == tcp_wfree
1703 #endif
1704 ) {
1705 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1706 skb->truesize = 1;
1707 } else {
1708 skb_orphan(skb);
1709 }
1710 }
1711 EXPORT_SYMBOL(skb_orphan_partial);
1712
1713 /*
1714 * Read buffer destructor automatically called from kfree_skb.
1715 */
1716 void sock_rfree(struct sk_buff *skb)
1717 {
1718 struct sock *sk = skb->sk;
1719 unsigned int len = skb->truesize;
1720
1721 atomic_sub(len, &sk->sk_rmem_alloc);
1722 sk_mem_uncharge(sk, len);
1723 }
1724 EXPORT_SYMBOL(sock_rfree);
1725
1726 /*
1727 * Buffer destructor for skbs that are not used directly in read or write
1728 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1729 */
1730 void sock_efree(struct sk_buff *skb)
1731 {
1732 sock_put(skb->sk);
1733 }
1734 EXPORT_SYMBOL(sock_efree);
1735
1736 kuid_t sock_i_uid(struct sock *sk)
1737 {
1738 kuid_t uid;
1739
1740 read_lock_bh(&sk->sk_callback_lock);
1741 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1742 read_unlock_bh(&sk->sk_callback_lock);
1743 return uid;
1744 }
1745 EXPORT_SYMBOL(sock_i_uid);
1746
1747 unsigned long sock_i_ino(struct sock *sk)
1748 {
1749 unsigned long ino;
1750
1751 read_lock_bh(&sk->sk_callback_lock);
1752 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1753 read_unlock_bh(&sk->sk_callback_lock);
1754 return ino;
1755 }
1756 EXPORT_SYMBOL(sock_i_ino);
1757
1758 /*
1759 * Allocate a skb from the socket's send buffer.
1760 */
1761 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1762 gfp_t priority)
1763 {
1764 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1765 struct sk_buff *skb = alloc_skb(size, priority);
1766 if (skb) {
1767 skb_set_owner_w(skb, sk);
1768 return skb;
1769 }
1770 }
1771 return NULL;
1772 }
1773 EXPORT_SYMBOL(sock_wmalloc);
1774
1775 /*
1776 * Allocate a memory block from the socket's option memory buffer.
1777 */
1778 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1779 {
1780 if ((unsigned int)size <= sysctl_optmem_max &&
1781 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1782 void *mem;
1783 /* First do the add, to avoid the race if kmalloc
1784 * might sleep.
1785 */
1786 atomic_add(size, &sk->sk_omem_alloc);
1787 mem = kmalloc(size, priority);
1788 if (mem)
1789 return mem;
1790 atomic_sub(size, &sk->sk_omem_alloc);
1791 }
1792 return NULL;
1793 }
1794 EXPORT_SYMBOL(sock_kmalloc);
1795
1796 /* Free an option memory block. Note, we actually want the inline
1797 * here as this allows gcc to detect the nullify and fold away the
1798 * condition entirely.
1799 */
1800 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1801 const bool nullify)
1802 {
1803 if (WARN_ON_ONCE(!mem))
1804 return;
1805 if (nullify)
1806 kzfree(mem);
1807 else
1808 kfree(mem);
1809 atomic_sub(size, &sk->sk_omem_alloc);
1810 }
1811
1812 void sock_kfree_s(struct sock *sk, void *mem, int size)
1813 {
1814 __sock_kfree_s(sk, mem, size, false);
1815 }
1816 EXPORT_SYMBOL(sock_kfree_s);
1817
1818 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1819 {
1820 __sock_kfree_s(sk, mem, size, true);
1821 }
1822 EXPORT_SYMBOL(sock_kzfree_s);
1823
1824 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1825 I think, these locks should be removed for datagram sockets.
1826 */
1827 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1828 {
1829 DEFINE_WAIT(wait);
1830
1831 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1832 for (;;) {
1833 if (!timeo)
1834 break;
1835 if (signal_pending(current))
1836 break;
1837 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1838 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1839 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1840 break;
1841 if (sk->sk_shutdown & SEND_SHUTDOWN)
1842 break;
1843 if (sk->sk_err)
1844 break;
1845 timeo = schedule_timeout(timeo);
1846 }
1847 finish_wait(sk_sleep(sk), &wait);
1848 return timeo;
1849 }
1850
1851
1852 /*
1853 * Generic send/receive buffer handlers
1854 */
1855
1856 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1857 unsigned long data_len, int noblock,
1858 int *errcode, int max_page_order)
1859 {
1860 struct sk_buff *skb;
1861 long timeo;
1862 int err;
1863
1864 timeo = sock_sndtimeo(sk, noblock);
1865 for (;;) {
1866 err = sock_error(sk);
1867 if (err != 0)
1868 goto failure;
1869
1870 err = -EPIPE;
1871 if (sk->sk_shutdown & SEND_SHUTDOWN)
1872 goto failure;
1873
1874 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1875 break;
1876
1877 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1878 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1879 err = -EAGAIN;
1880 if (!timeo)
1881 goto failure;
1882 if (signal_pending(current))
1883 goto interrupted;
1884 timeo = sock_wait_for_wmem(sk, timeo);
1885 }
1886 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1887 errcode, sk->sk_allocation);
1888 if (skb)
1889 skb_set_owner_w(skb, sk);
1890 return skb;
1891
1892 interrupted:
1893 err = sock_intr_errno(timeo);
1894 failure:
1895 *errcode = err;
1896 return NULL;
1897 }
1898 EXPORT_SYMBOL(sock_alloc_send_pskb);
1899
1900 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1901 int noblock, int *errcode)
1902 {
1903 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1904 }
1905 EXPORT_SYMBOL(sock_alloc_send_skb);
1906
1907 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1908 struct sockcm_cookie *sockc)
1909 {
1910 struct cmsghdr *cmsg;
1911
1912 for_each_cmsghdr(cmsg, msg) {
1913 if (!CMSG_OK(msg, cmsg))
1914 return -EINVAL;
1915 if (cmsg->cmsg_level != SOL_SOCKET)
1916 continue;
1917 switch (cmsg->cmsg_type) {
1918 case SO_MARK:
1919 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1920 return -EPERM;
1921 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1922 return -EINVAL;
1923 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
1924 break;
1925 default:
1926 return -EINVAL;
1927 }
1928 }
1929 return 0;
1930 }
1931 EXPORT_SYMBOL(sock_cmsg_send);
1932
1933 /* On 32bit arches, an skb frag is limited to 2^15 */
1934 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1935
1936 /**
1937 * skb_page_frag_refill - check that a page_frag contains enough room
1938 * @sz: minimum size of the fragment we want to get
1939 * @pfrag: pointer to page_frag
1940 * @gfp: priority for memory allocation
1941 *
1942 * Note: While this allocator tries to use high order pages, there is
1943 * no guarantee that allocations succeed. Therefore, @sz MUST be
1944 * less or equal than PAGE_SIZE.
1945 */
1946 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1947 {
1948 if (pfrag->page) {
1949 if (atomic_read(&pfrag->page->_count) == 1) {
1950 pfrag->offset = 0;
1951 return true;
1952 }
1953 if (pfrag->offset + sz <= pfrag->size)
1954 return true;
1955 put_page(pfrag->page);
1956 }
1957
1958 pfrag->offset = 0;
1959 if (SKB_FRAG_PAGE_ORDER) {
1960 /* Avoid direct reclaim but allow kswapd to wake */
1961 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
1962 __GFP_COMP | __GFP_NOWARN |
1963 __GFP_NORETRY,
1964 SKB_FRAG_PAGE_ORDER);
1965 if (likely(pfrag->page)) {
1966 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1967 return true;
1968 }
1969 }
1970 pfrag->page = alloc_page(gfp);
1971 if (likely(pfrag->page)) {
1972 pfrag->size = PAGE_SIZE;
1973 return true;
1974 }
1975 return false;
1976 }
1977 EXPORT_SYMBOL(skb_page_frag_refill);
1978
1979 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1980 {
1981 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1982 return true;
1983
1984 sk_enter_memory_pressure(sk);
1985 sk_stream_moderate_sndbuf(sk);
1986 return false;
1987 }
1988 EXPORT_SYMBOL(sk_page_frag_refill);
1989
1990 static void __lock_sock(struct sock *sk)
1991 __releases(&sk->sk_lock.slock)
1992 __acquires(&sk->sk_lock.slock)
1993 {
1994 DEFINE_WAIT(wait);
1995
1996 for (;;) {
1997 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1998 TASK_UNINTERRUPTIBLE);
1999 spin_unlock_bh(&sk->sk_lock.slock);
2000 schedule();
2001 spin_lock_bh(&sk->sk_lock.slock);
2002 if (!sock_owned_by_user(sk))
2003 break;
2004 }
2005 finish_wait(&sk->sk_lock.wq, &wait);
2006 }
2007
2008 static void __release_sock(struct sock *sk)
2009 __releases(&sk->sk_lock.slock)
2010 __acquires(&sk->sk_lock.slock)
2011 {
2012 struct sk_buff *skb = sk->sk_backlog.head;
2013
2014 do {
2015 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2016 bh_unlock_sock(sk);
2017
2018 do {
2019 struct sk_buff *next = skb->next;
2020
2021 prefetch(next);
2022 WARN_ON_ONCE(skb_dst_is_noref(skb));
2023 skb->next = NULL;
2024 sk_backlog_rcv(sk, skb);
2025
2026 /*
2027 * We are in process context here with softirqs
2028 * disabled, use cond_resched_softirq() to preempt.
2029 * This is safe to do because we've taken the backlog
2030 * queue private:
2031 */
2032 cond_resched_softirq();
2033
2034 skb = next;
2035 } while (skb != NULL);
2036
2037 bh_lock_sock(sk);
2038 } while ((skb = sk->sk_backlog.head) != NULL);
2039
2040 /*
2041 * Doing the zeroing here guarantee we can not loop forever
2042 * while a wild producer attempts to flood us.
2043 */
2044 sk->sk_backlog.len = 0;
2045 }
2046
2047 /**
2048 * sk_wait_data - wait for data to arrive at sk_receive_queue
2049 * @sk: sock to wait on
2050 * @timeo: for how long
2051 * @skb: last skb seen on sk_receive_queue
2052 *
2053 * Now socket state including sk->sk_err is changed only under lock,
2054 * hence we may omit checks after joining wait queue.
2055 * We check receive queue before schedule() only as optimization;
2056 * it is very likely that release_sock() added new data.
2057 */
2058 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2059 {
2060 int rc;
2061 DEFINE_WAIT(wait);
2062
2063 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2064 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2065 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb);
2066 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2067 finish_wait(sk_sleep(sk), &wait);
2068 return rc;
2069 }
2070 EXPORT_SYMBOL(sk_wait_data);
2071
2072 /**
2073 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2074 * @sk: socket
2075 * @size: memory size to allocate
2076 * @kind: allocation type
2077 *
2078 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2079 * rmem allocation. This function assumes that protocols which have
2080 * memory_pressure use sk_wmem_queued as write buffer accounting.
2081 */
2082 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2083 {
2084 struct proto *prot = sk->sk_prot;
2085 int amt = sk_mem_pages(size);
2086 long allocated;
2087
2088 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2089
2090 allocated = sk_memory_allocated_add(sk, amt);
2091
2092 if (mem_cgroup_sockets_enabled && sk->sk_cgrp &&
2093 !mem_cgroup_charge_skmem(sk->sk_cgrp, amt))
2094 goto suppress_allocation;
2095
2096 /* Under limit. */
2097 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2098 sk_leave_memory_pressure(sk);
2099 return 1;
2100 }
2101
2102 /* Under pressure. */
2103 if (allocated > sk_prot_mem_limits(sk, 1))
2104 sk_enter_memory_pressure(sk);
2105
2106 /* Over hard limit. */
2107 if (allocated > sk_prot_mem_limits(sk, 2))
2108 goto suppress_allocation;
2109
2110 /* guarantee minimum buffer size under pressure */
2111 if (kind == SK_MEM_RECV) {
2112 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2113 return 1;
2114
2115 } else { /* SK_MEM_SEND */
2116 if (sk->sk_type == SOCK_STREAM) {
2117 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2118 return 1;
2119 } else if (atomic_read(&sk->sk_wmem_alloc) <
2120 prot->sysctl_wmem[0])
2121 return 1;
2122 }
2123
2124 if (sk_has_memory_pressure(sk)) {
2125 int alloc;
2126
2127 if (!sk_under_memory_pressure(sk))
2128 return 1;
2129 alloc = sk_sockets_allocated_read_positive(sk);
2130 if (sk_prot_mem_limits(sk, 2) > alloc *
2131 sk_mem_pages(sk->sk_wmem_queued +
2132 atomic_read(&sk->sk_rmem_alloc) +
2133 sk->sk_forward_alloc))
2134 return 1;
2135 }
2136
2137 suppress_allocation:
2138
2139 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2140 sk_stream_moderate_sndbuf(sk);
2141
2142 /* Fail only if socket is _under_ its sndbuf.
2143 * In this case we cannot block, so that we have to fail.
2144 */
2145 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2146 return 1;
2147 }
2148
2149 trace_sock_exceed_buf_limit(sk, prot, allocated);
2150
2151 /* Alas. Undo changes. */
2152 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2153
2154 sk_memory_allocated_sub(sk, amt);
2155
2156 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
2157 mem_cgroup_uncharge_skmem(sk->sk_cgrp, amt);
2158
2159 return 0;
2160 }
2161 EXPORT_SYMBOL(__sk_mem_schedule);
2162
2163 /**
2164 * __sk_mem_reclaim - reclaim memory_allocated
2165 * @sk: socket
2166 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2167 */
2168 void __sk_mem_reclaim(struct sock *sk, int amount)
2169 {
2170 amount >>= SK_MEM_QUANTUM_SHIFT;
2171 sk_memory_allocated_sub(sk, amount);
2172 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2173
2174 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
2175 mem_cgroup_uncharge_skmem(sk->sk_cgrp, amount);
2176
2177 if (sk_under_memory_pressure(sk) &&
2178 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2179 sk_leave_memory_pressure(sk);
2180 }
2181 EXPORT_SYMBOL(__sk_mem_reclaim);
2182
2183
2184 /*
2185 * Set of default routines for initialising struct proto_ops when
2186 * the protocol does not support a particular function. In certain
2187 * cases where it makes no sense for a protocol to have a "do nothing"
2188 * function, some default processing is provided.
2189 */
2190
2191 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2192 {
2193 return -EOPNOTSUPP;
2194 }
2195 EXPORT_SYMBOL(sock_no_bind);
2196
2197 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2198 int len, int flags)
2199 {
2200 return -EOPNOTSUPP;
2201 }
2202 EXPORT_SYMBOL(sock_no_connect);
2203
2204 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2205 {
2206 return -EOPNOTSUPP;
2207 }
2208 EXPORT_SYMBOL(sock_no_socketpair);
2209
2210 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2211 {
2212 return -EOPNOTSUPP;
2213 }
2214 EXPORT_SYMBOL(sock_no_accept);
2215
2216 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2217 int *len, int peer)
2218 {
2219 return -EOPNOTSUPP;
2220 }
2221 EXPORT_SYMBOL(sock_no_getname);
2222
2223 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2224 {
2225 return 0;
2226 }
2227 EXPORT_SYMBOL(sock_no_poll);
2228
2229 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2230 {
2231 return -EOPNOTSUPP;
2232 }
2233 EXPORT_SYMBOL(sock_no_ioctl);
2234
2235 int sock_no_listen(struct socket *sock, int backlog)
2236 {
2237 return -EOPNOTSUPP;
2238 }
2239 EXPORT_SYMBOL(sock_no_listen);
2240
2241 int sock_no_shutdown(struct socket *sock, int how)
2242 {
2243 return -EOPNOTSUPP;
2244 }
2245 EXPORT_SYMBOL(sock_no_shutdown);
2246
2247 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2248 char __user *optval, unsigned int optlen)
2249 {
2250 return -EOPNOTSUPP;
2251 }
2252 EXPORT_SYMBOL(sock_no_setsockopt);
2253
2254 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2255 char __user *optval, int __user *optlen)
2256 {
2257 return -EOPNOTSUPP;
2258 }
2259 EXPORT_SYMBOL(sock_no_getsockopt);
2260
2261 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2262 {
2263 return -EOPNOTSUPP;
2264 }
2265 EXPORT_SYMBOL(sock_no_sendmsg);
2266
2267 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2268 int flags)
2269 {
2270 return -EOPNOTSUPP;
2271 }
2272 EXPORT_SYMBOL(sock_no_recvmsg);
2273
2274 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2275 {
2276 /* Mirror missing mmap method error code */
2277 return -ENODEV;
2278 }
2279 EXPORT_SYMBOL(sock_no_mmap);
2280
2281 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2282 {
2283 ssize_t res;
2284 struct msghdr msg = {.msg_flags = flags};
2285 struct kvec iov;
2286 char *kaddr = kmap(page);
2287 iov.iov_base = kaddr + offset;
2288 iov.iov_len = size;
2289 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2290 kunmap(page);
2291 return res;
2292 }
2293 EXPORT_SYMBOL(sock_no_sendpage);
2294
2295 /*
2296 * Default Socket Callbacks
2297 */
2298
2299 static void sock_def_wakeup(struct sock *sk)
2300 {
2301 struct socket_wq *wq;
2302
2303 rcu_read_lock();
2304 wq = rcu_dereference(sk->sk_wq);
2305 if (skwq_has_sleeper(wq))
2306 wake_up_interruptible_all(&wq->wait);
2307 rcu_read_unlock();
2308 }
2309
2310 static void sock_def_error_report(struct sock *sk)
2311 {
2312 struct socket_wq *wq;
2313
2314 rcu_read_lock();
2315 wq = rcu_dereference(sk->sk_wq);
2316 if (skwq_has_sleeper(wq))
2317 wake_up_interruptible_poll(&wq->wait, POLLERR);
2318 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2319 rcu_read_unlock();
2320 }
2321
2322 static void sock_def_readable(struct sock *sk)
2323 {
2324 struct socket_wq *wq;
2325
2326 rcu_read_lock();
2327 wq = rcu_dereference(sk->sk_wq);
2328 if (skwq_has_sleeper(wq))
2329 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2330 POLLRDNORM | POLLRDBAND);
2331 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2332 rcu_read_unlock();
2333 }
2334
2335 static void sock_def_write_space(struct sock *sk)
2336 {
2337 struct socket_wq *wq;
2338
2339 rcu_read_lock();
2340
2341 /* Do not wake up a writer until he can make "significant"
2342 * progress. --DaveM
2343 */
2344 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2345 wq = rcu_dereference(sk->sk_wq);
2346 if (skwq_has_sleeper(wq))
2347 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2348 POLLWRNORM | POLLWRBAND);
2349
2350 /* Should agree with poll, otherwise some programs break */
2351 if (sock_writeable(sk))
2352 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2353 }
2354
2355 rcu_read_unlock();
2356 }
2357
2358 static void sock_def_destruct(struct sock *sk)
2359 {
2360 }
2361
2362 void sk_send_sigurg(struct sock *sk)
2363 {
2364 if (sk->sk_socket && sk->sk_socket->file)
2365 if (send_sigurg(&sk->sk_socket->file->f_owner))
2366 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2367 }
2368 EXPORT_SYMBOL(sk_send_sigurg);
2369
2370 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2371 unsigned long expires)
2372 {
2373 if (!mod_timer(timer, expires))
2374 sock_hold(sk);
2375 }
2376 EXPORT_SYMBOL(sk_reset_timer);
2377
2378 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2379 {
2380 if (del_timer(timer))
2381 __sock_put(sk);
2382 }
2383 EXPORT_SYMBOL(sk_stop_timer);
2384
2385 void sock_init_data(struct socket *sock, struct sock *sk)
2386 {
2387 skb_queue_head_init(&sk->sk_receive_queue);
2388 skb_queue_head_init(&sk->sk_write_queue);
2389 skb_queue_head_init(&sk->sk_error_queue);
2390
2391 sk->sk_send_head = NULL;
2392
2393 init_timer(&sk->sk_timer);
2394
2395 sk->sk_allocation = GFP_KERNEL;
2396 sk->sk_rcvbuf = sysctl_rmem_default;
2397 sk->sk_sndbuf = sysctl_wmem_default;
2398 sk->sk_state = TCP_CLOSE;
2399 sk_set_socket(sk, sock);
2400
2401 sock_set_flag(sk, SOCK_ZAPPED);
2402
2403 if (sock) {
2404 sk->sk_type = sock->type;
2405 sk->sk_wq = sock->wq;
2406 sock->sk = sk;
2407 } else
2408 sk->sk_wq = NULL;
2409
2410 rwlock_init(&sk->sk_callback_lock);
2411 lockdep_set_class_and_name(&sk->sk_callback_lock,
2412 af_callback_keys + sk->sk_family,
2413 af_family_clock_key_strings[sk->sk_family]);
2414
2415 sk->sk_state_change = sock_def_wakeup;
2416 sk->sk_data_ready = sock_def_readable;
2417 sk->sk_write_space = sock_def_write_space;
2418 sk->sk_error_report = sock_def_error_report;
2419 sk->sk_destruct = sock_def_destruct;
2420
2421 sk->sk_frag.page = NULL;
2422 sk->sk_frag.offset = 0;
2423 sk->sk_peek_off = -1;
2424
2425 sk->sk_peer_pid = NULL;
2426 sk->sk_peer_cred = NULL;
2427 sk->sk_write_pending = 0;
2428 sk->sk_rcvlowat = 1;
2429 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2430 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2431
2432 sk->sk_stamp = ktime_set(-1L, 0);
2433
2434 #ifdef CONFIG_NET_RX_BUSY_POLL
2435 sk->sk_napi_id = 0;
2436 sk->sk_ll_usec = sysctl_net_busy_read;
2437 #endif
2438
2439 sk->sk_max_pacing_rate = ~0U;
2440 sk->sk_pacing_rate = ~0U;
2441 sk->sk_incoming_cpu = -1;
2442 /*
2443 * Before updating sk_refcnt, we must commit prior changes to memory
2444 * (Documentation/RCU/rculist_nulls.txt for details)
2445 */
2446 smp_wmb();
2447 atomic_set(&sk->sk_refcnt, 1);
2448 atomic_set(&sk->sk_drops, 0);
2449 }
2450 EXPORT_SYMBOL(sock_init_data);
2451
2452 void lock_sock_nested(struct sock *sk, int subclass)
2453 {
2454 might_sleep();
2455 spin_lock_bh(&sk->sk_lock.slock);
2456 if (sk->sk_lock.owned)
2457 __lock_sock(sk);
2458 sk->sk_lock.owned = 1;
2459 spin_unlock(&sk->sk_lock.slock);
2460 /*
2461 * The sk_lock has mutex_lock() semantics here:
2462 */
2463 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2464 local_bh_enable();
2465 }
2466 EXPORT_SYMBOL(lock_sock_nested);
2467
2468 void release_sock(struct sock *sk)
2469 {
2470 /*
2471 * The sk_lock has mutex_unlock() semantics:
2472 */
2473 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2474
2475 spin_lock_bh(&sk->sk_lock.slock);
2476 if (sk->sk_backlog.tail)
2477 __release_sock(sk);
2478
2479 /* Warning : release_cb() might need to release sk ownership,
2480 * ie call sock_release_ownership(sk) before us.
2481 */
2482 if (sk->sk_prot->release_cb)
2483 sk->sk_prot->release_cb(sk);
2484
2485 sock_release_ownership(sk);
2486 if (waitqueue_active(&sk->sk_lock.wq))
2487 wake_up(&sk->sk_lock.wq);
2488 spin_unlock_bh(&sk->sk_lock.slock);
2489 }
2490 EXPORT_SYMBOL(release_sock);
2491
2492 /**
2493 * lock_sock_fast - fast version of lock_sock
2494 * @sk: socket
2495 *
2496 * This version should be used for very small section, where process wont block
2497 * return false if fast path is taken
2498 * sk_lock.slock locked, owned = 0, BH disabled
2499 * return true if slow path is taken
2500 * sk_lock.slock unlocked, owned = 1, BH enabled
2501 */
2502 bool lock_sock_fast(struct sock *sk)
2503 {
2504 might_sleep();
2505 spin_lock_bh(&sk->sk_lock.slock);
2506
2507 if (!sk->sk_lock.owned)
2508 /*
2509 * Note : We must disable BH
2510 */
2511 return false;
2512
2513 __lock_sock(sk);
2514 sk->sk_lock.owned = 1;
2515 spin_unlock(&sk->sk_lock.slock);
2516 /*
2517 * The sk_lock has mutex_lock() semantics here:
2518 */
2519 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2520 local_bh_enable();
2521 return true;
2522 }
2523 EXPORT_SYMBOL(lock_sock_fast);
2524
2525 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2526 {
2527 struct timeval tv;
2528 if (!sock_flag(sk, SOCK_TIMESTAMP))
2529 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2530 tv = ktime_to_timeval(sk->sk_stamp);
2531 if (tv.tv_sec == -1)
2532 return -ENOENT;
2533 if (tv.tv_sec == 0) {
2534 sk->sk_stamp = ktime_get_real();
2535 tv = ktime_to_timeval(sk->sk_stamp);
2536 }
2537 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2538 }
2539 EXPORT_SYMBOL(sock_get_timestamp);
2540
2541 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2542 {
2543 struct timespec ts;
2544 if (!sock_flag(sk, SOCK_TIMESTAMP))
2545 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2546 ts = ktime_to_timespec(sk->sk_stamp);
2547 if (ts.tv_sec == -1)
2548 return -ENOENT;
2549 if (ts.tv_sec == 0) {
2550 sk->sk_stamp = ktime_get_real();
2551 ts = ktime_to_timespec(sk->sk_stamp);
2552 }
2553 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2554 }
2555 EXPORT_SYMBOL(sock_get_timestampns);
2556
2557 void sock_enable_timestamp(struct sock *sk, int flag)
2558 {
2559 if (!sock_flag(sk, flag)) {
2560 unsigned long previous_flags = sk->sk_flags;
2561
2562 sock_set_flag(sk, flag);
2563 /*
2564 * we just set one of the two flags which require net
2565 * time stamping, but time stamping might have been on
2566 * already because of the other one
2567 */
2568 if (sock_needs_netstamp(sk) &&
2569 !(previous_flags & SK_FLAGS_TIMESTAMP))
2570 net_enable_timestamp();
2571 }
2572 }
2573
2574 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2575 int level, int type)
2576 {
2577 struct sock_exterr_skb *serr;
2578 struct sk_buff *skb;
2579 int copied, err;
2580
2581 err = -EAGAIN;
2582 skb = sock_dequeue_err_skb(sk);
2583 if (skb == NULL)
2584 goto out;
2585
2586 copied = skb->len;
2587 if (copied > len) {
2588 msg->msg_flags |= MSG_TRUNC;
2589 copied = len;
2590 }
2591 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2592 if (err)
2593 goto out_free_skb;
2594
2595 sock_recv_timestamp(msg, sk, skb);
2596
2597 serr = SKB_EXT_ERR(skb);
2598 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2599
2600 msg->msg_flags |= MSG_ERRQUEUE;
2601 err = copied;
2602
2603 out_free_skb:
2604 kfree_skb(skb);
2605 out:
2606 return err;
2607 }
2608 EXPORT_SYMBOL(sock_recv_errqueue);
2609
2610 /*
2611 * Get a socket option on an socket.
2612 *
2613 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2614 * asynchronous errors should be reported by getsockopt. We assume
2615 * this means if you specify SO_ERROR (otherwise whats the point of it).
2616 */
2617 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2618 char __user *optval, int __user *optlen)
2619 {
2620 struct sock *sk = sock->sk;
2621
2622 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2623 }
2624 EXPORT_SYMBOL(sock_common_getsockopt);
2625
2626 #ifdef CONFIG_COMPAT
2627 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2628 char __user *optval, int __user *optlen)
2629 {
2630 struct sock *sk = sock->sk;
2631
2632 if (sk->sk_prot->compat_getsockopt != NULL)
2633 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2634 optval, optlen);
2635 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2636 }
2637 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2638 #endif
2639
2640 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2641 int flags)
2642 {
2643 struct sock *sk = sock->sk;
2644 int addr_len = 0;
2645 int err;
2646
2647 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2648 flags & ~MSG_DONTWAIT, &addr_len);
2649 if (err >= 0)
2650 msg->msg_namelen = addr_len;
2651 return err;
2652 }
2653 EXPORT_SYMBOL(sock_common_recvmsg);
2654
2655 /*
2656 * Set socket options on an inet socket.
2657 */
2658 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2659 char __user *optval, unsigned int optlen)
2660 {
2661 struct sock *sk = sock->sk;
2662
2663 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2664 }
2665 EXPORT_SYMBOL(sock_common_setsockopt);
2666
2667 #ifdef CONFIG_COMPAT
2668 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2669 char __user *optval, unsigned int optlen)
2670 {
2671 struct sock *sk = sock->sk;
2672
2673 if (sk->sk_prot->compat_setsockopt != NULL)
2674 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2675 optval, optlen);
2676 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2677 }
2678 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2679 #endif
2680
2681 void sk_common_release(struct sock *sk)
2682 {
2683 if (sk->sk_prot->destroy)
2684 sk->sk_prot->destroy(sk);
2685
2686 /*
2687 * Observation: when sock_common_release is called, processes have
2688 * no access to socket. But net still has.
2689 * Step one, detach it from networking:
2690 *
2691 * A. Remove from hash tables.
2692 */
2693
2694 sk->sk_prot->unhash(sk);
2695
2696 /*
2697 * In this point socket cannot receive new packets, but it is possible
2698 * that some packets are in flight because some CPU runs receiver and
2699 * did hash table lookup before we unhashed socket. They will achieve
2700 * receive queue and will be purged by socket destructor.
2701 *
2702 * Also we still have packets pending on receive queue and probably,
2703 * our own packets waiting in device queues. sock_destroy will drain
2704 * receive queue, but transmitted packets will delay socket destruction
2705 * until the last reference will be released.
2706 */
2707
2708 sock_orphan(sk);
2709
2710 xfrm_sk_free_policy(sk);
2711
2712 sk_refcnt_debug_release(sk);
2713
2714 if (sk->sk_frag.page) {
2715 put_page(sk->sk_frag.page);
2716 sk->sk_frag.page = NULL;
2717 }
2718
2719 sock_put(sk);
2720 }
2721 EXPORT_SYMBOL(sk_common_release);
2722
2723 #ifdef CONFIG_PROC_FS
2724 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2725 struct prot_inuse {
2726 int val[PROTO_INUSE_NR];
2727 };
2728
2729 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2730
2731 #ifdef CONFIG_NET_NS
2732 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2733 {
2734 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2735 }
2736 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2737
2738 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2739 {
2740 int cpu, idx = prot->inuse_idx;
2741 int res = 0;
2742
2743 for_each_possible_cpu(cpu)
2744 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2745
2746 return res >= 0 ? res : 0;
2747 }
2748 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2749
2750 static int __net_init sock_inuse_init_net(struct net *net)
2751 {
2752 net->core.inuse = alloc_percpu(struct prot_inuse);
2753 return net->core.inuse ? 0 : -ENOMEM;
2754 }
2755
2756 static void __net_exit sock_inuse_exit_net(struct net *net)
2757 {
2758 free_percpu(net->core.inuse);
2759 }
2760
2761 static struct pernet_operations net_inuse_ops = {
2762 .init = sock_inuse_init_net,
2763 .exit = sock_inuse_exit_net,
2764 };
2765
2766 static __init int net_inuse_init(void)
2767 {
2768 if (register_pernet_subsys(&net_inuse_ops))
2769 panic("Cannot initialize net inuse counters");
2770
2771 return 0;
2772 }
2773
2774 core_initcall(net_inuse_init);
2775 #else
2776 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2777
2778 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2779 {
2780 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2781 }
2782 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2783
2784 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2785 {
2786 int cpu, idx = prot->inuse_idx;
2787 int res = 0;
2788
2789 for_each_possible_cpu(cpu)
2790 res += per_cpu(prot_inuse, cpu).val[idx];
2791
2792 return res >= 0 ? res : 0;
2793 }
2794 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2795 #endif
2796
2797 static void assign_proto_idx(struct proto *prot)
2798 {
2799 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2800
2801 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2802 pr_err("PROTO_INUSE_NR exhausted\n");
2803 return;
2804 }
2805
2806 set_bit(prot->inuse_idx, proto_inuse_idx);
2807 }
2808
2809 static void release_proto_idx(struct proto *prot)
2810 {
2811 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2812 clear_bit(prot->inuse_idx, proto_inuse_idx);
2813 }
2814 #else
2815 static inline void assign_proto_idx(struct proto *prot)
2816 {
2817 }
2818
2819 static inline void release_proto_idx(struct proto *prot)
2820 {
2821 }
2822 #endif
2823
2824 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2825 {
2826 if (!rsk_prot)
2827 return;
2828 kfree(rsk_prot->slab_name);
2829 rsk_prot->slab_name = NULL;
2830 kmem_cache_destroy(rsk_prot->slab);
2831 rsk_prot->slab = NULL;
2832 }
2833
2834 static int req_prot_init(const struct proto *prot)
2835 {
2836 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2837
2838 if (!rsk_prot)
2839 return 0;
2840
2841 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2842 prot->name);
2843 if (!rsk_prot->slab_name)
2844 return -ENOMEM;
2845
2846 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2847 rsk_prot->obj_size, 0,
2848 prot->slab_flags, NULL);
2849
2850 if (!rsk_prot->slab) {
2851 pr_crit("%s: Can't create request sock SLAB cache!\n",
2852 prot->name);
2853 return -ENOMEM;
2854 }
2855 return 0;
2856 }
2857
2858 int proto_register(struct proto *prot, int alloc_slab)
2859 {
2860 if (alloc_slab) {
2861 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2862 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2863 NULL);
2864
2865 if (prot->slab == NULL) {
2866 pr_crit("%s: Can't create sock SLAB cache!\n",
2867 prot->name);
2868 goto out;
2869 }
2870
2871 if (req_prot_init(prot))
2872 goto out_free_request_sock_slab;
2873
2874 if (prot->twsk_prot != NULL) {
2875 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2876
2877 if (prot->twsk_prot->twsk_slab_name == NULL)
2878 goto out_free_request_sock_slab;
2879
2880 prot->twsk_prot->twsk_slab =
2881 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2882 prot->twsk_prot->twsk_obj_size,
2883 0,
2884 prot->slab_flags,
2885 NULL);
2886 if (prot->twsk_prot->twsk_slab == NULL)
2887 goto out_free_timewait_sock_slab_name;
2888 }
2889 }
2890
2891 mutex_lock(&proto_list_mutex);
2892 list_add(&prot->node, &proto_list);
2893 assign_proto_idx(prot);
2894 mutex_unlock(&proto_list_mutex);
2895 return 0;
2896
2897 out_free_timewait_sock_slab_name:
2898 kfree(prot->twsk_prot->twsk_slab_name);
2899 out_free_request_sock_slab:
2900 req_prot_cleanup(prot->rsk_prot);
2901
2902 kmem_cache_destroy(prot->slab);
2903 prot->slab = NULL;
2904 out:
2905 return -ENOBUFS;
2906 }
2907 EXPORT_SYMBOL(proto_register);
2908
2909 void proto_unregister(struct proto *prot)
2910 {
2911 mutex_lock(&proto_list_mutex);
2912 release_proto_idx(prot);
2913 list_del(&prot->node);
2914 mutex_unlock(&proto_list_mutex);
2915
2916 kmem_cache_destroy(prot->slab);
2917 prot->slab = NULL;
2918
2919 req_prot_cleanup(prot->rsk_prot);
2920
2921 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2922 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2923 kfree(prot->twsk_prot->twsk_slab_name);
2924 prot->twsk_prot->twsk_slab = NULL;
2925 }
2926 }
2927 EXPORT_SYMBOL(proto_unregister);
2928
2929 #ifdef CONFIG_PROC_FS
2930 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2931 __acquires(proto_list_mutex)
2932 {
2933 mutex_lock(&proto_list_mutex);
2934 return seq_list_start_head(&proto_list, *pos);
2935 }
2936
2937 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2938 {
2939 return seq_list_next(v, &proto_list, pos);
2940 }
2941
2942 static void proto_seq_stop(struct seq_file *seq, void *v)
2943 __releases(proto_list_mutex)
2944 {
2945 mutex_unlock(&proto_list_mutex);
2946 }
2947
2948 static char proto_method_implemented(const void *method)
2949 {
2950 return method == NULL ? 'n' : 'y';
2951 }
2952 static long sock_prot_memory_allocated(struct proto *proto)
2953 {
2954 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2955 }
2956
2957 static char *sock_prot_memory_pressure(struct proto *proto)
2958 {
2959 return proto->memory_pressure != NULL ?
2960 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2961 }
2962
2963 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2964 {
2965
2966 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2967 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2968 proto->name,
2969 proto->obj_size,
2970 sock_prot_inuse_get(seq_file_net(seq), proto),
2971 sock_prot_memory_allocated(proto),
2972 sock_prot_memory_pressure(proto),
2973 proto->max_header,
2974 proto->slab == NULL ? "no" : "yes",
2975 module_name(proto->owner),
2976 proto_method_implemented(proto->close),
2977 proto_method_implemented(proto->connect),
2978 proto_method_implemented(proto->disconnect),
2979 proto_method_implemented(proto->accept),
2980 proto_method_implemented(proto->ioctl),
2981 proto_method_implemented(proto->init),
2982 proto_method_implemented(proto->destroy),
2983 proto_method_implemented(proto->shutdown),
2984 proto_method_implemented(proto->setsockopt),
2985 proto_method_implemented(proto->getsockopt),
2986 proto_method_implemented(proto->sendmsg),
2987 proto_method_implemented(proto->recvmsg),
2988 proto_method_implemented(proto->sendpage),
2989 proto_method_implemented(proto->bind),
2990 proto_method_implemented(proto->backlog_rcv),
2991 proto_method_implemented(proto->hash),
2992 proto_method_implemented(proto->unhash),
2993 proto_method_implemented(proto->get_port),
2994 proto_method_implemented(proto->enter_memory_pressure));
2995 }
2996
2997 static int proto_seq_show(struct seq_file *seq, void *v)
2998 {
2999 if (v == &proto_list)
3000 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3001 "protocol",
3002 "size",
3003 "sockets",
3004 "memory",
3005 "press",
3006 "maxhdr",
3007 "slab",
3008 "module",
3009 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3010 else
3011 proto_seq_printf(seq, list_entry(v, struct proto, node));
3012 return 0;
3013 }
3014
3015 static const struct seq_operations proto_seq_ops = {
3016 .start = proto_seq_start,
3017 .next = proto_seq_next,
3018 .stop = proto_seq_stop,
3019 .show = proto_seq_show,
3020 };
3021
3022 static int proto_seq_open(struct inode *inode, struct file *file)
3023 {
3024 return seq_open_net(inode, file, &proto_seq_ops,
3025 sizeof(struct seq_net_private));
3026 }
3027
3028 static const struct file_operations proto_seq_fops = {
3029 .owner = THIS_MODULE,
3030 .open = proto_seq_open,
3031 .read = seq_read,
3032 .llseek = seq_lseek,
3033 .release = seq_release_net,
3034 };
3035
3036 static __net_init int proto_init_net(struct net *net)
3037 {
3038 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3039 return -ENOMEM;
3040
3041 return 0;
3042 }
3043
3044 static __net_exit void proto_exit_net(struct net *net)
3045 {
3046 remove_proc_entry("protocols", net->proc_net);
3047 }
3048
3049
3050 static __net_initdata struct pernet_operations proto_net_ops = {
3051 .init = proto_init_net,
3052 .exit = proto_exit_net,
3053 };
3054
3055 static int __init proto_init(void)
3056 {
3057 return register_pernet_subsys(&proto_net_ops);
3058 }
3059
3060 subsys_initcall(proto_init);
3061
3062 #endif /* PROC_FS */
Linux kernel - Deliverables
This page took 0.091766 seconds and 6 git commands to generate.