?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
staging: rtl8192e: Fix UNNECESSARY_ELSE warning
[linux-2.6/btrfs-unstable.git] / net / core / sock.c
blob78e89eb7eb705624d3ff63324f5002ae10b51145
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. However, if SOCK_MEMALLOC is cleared while
358 * it has rmem allocations there is a risk that the user of the
359 * socket cannot make forward progress due to exceeding the rmem
360 * limits. By rights, sk_clear_memalloc() should only be called
361 * on sockets being torn down but warn and reset the accounting if
362 * that assumption breaks.
363 */
364 if (WARN_ON(sk->sk_forward_alloc))
365 sk_mem_reclaim(sk);
366 }
367 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
368
369 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
370 {
371 int ret;
372 unsigned long pflags = current->flags;
373
374 /* these should have been dropped before queueing */
375 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
376
377 current->flags |= PF_MEMALLOC;
378 ret = sk->sk_backlog_rcv(sk, skb);
379 tsk_restore_flags(current, pflags, PF_MEMALLOC);
380
381 return ret;
382 }
383 EXPORT_SYMBOL(__sk_backlog_rcv);
384
385 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
386 {
387 struct timeval tv;
388
389 if (optlen < sizeof(tv))
390 return -EINVAL;
391 if (copy_from_user(&tv, optval, sizeof(tv)))
392 return -EFAULT;
393 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
394 return -EDOM;
395
396 if (tv.tv_sec < 0) {
397 static int warned __read_mostly;
398
399 *timeo_p = 0;
400 if (warned < 10 && net_ratelimit()) {
401 warned++;
402 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
403 __func__, current->comm, task_pid_nr(current));
404 }
405 return 0;
406 }
407 *timeo_p = MAX_SCHEDULE_TIMEOUT;
408 if (tv.tv_sec == 0 && tv.tv_usec == 0)
409 return 0;
410 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
411 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
412 return 0;
413 }
414
415 static void sock_warn_obsolete_bsdism(const char *name)
416 {
417 static int warned;
418 static char warncomm[TASK_COMM_LEN];
419 if (strcmp(warncomm, current->comm) && warned < 5) {
420 strcpy(warncomm, current->comm);
421 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
422 warncomm, name);
423 warned++;
424 }
425 }
426
427 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
428
429 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
430 {
431 if (sk->sk_flags & flags) {
432 sk->sk_flags &= ~flags;
433 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
434 net_disable_timestamp();
435 }
436 }
437
438
439 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
440 {
441 int err;
442 unsigned long flags;
443 struct sk_buff_head *list = &sk->sk_receive_queue;
444
445 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
446 atomic_inc(&sk->sk_drops);
447 trace_sock_rcvqueue_full(sk, skb);
448 return -ENOMEM;
449 }
450
451 err = sk_filter(sk, skb);
452 if (err)
453 return err;
454
455 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
456 atomic_inc(&sk->sk_drops);
457 return -ENOBUFS;
458 }
459
460 skb->dev = NULL;
461 skb_set_owner_r(skb, sk);
462
463 /* we escape from rcu protected region, make sure we dont leak
464 * a norefcounted dst
465 */
466 skb_dst_force(skb);
467
468 spin_lock_irqsave(&list->lock, flags);
469 skb->dropcount = atomic_read(&sk->sk_drops);
470 __skb_queue_tail(list, skb);
471 spin_unlock_irqrestore(&list->lock, flags);
472
473 if (!sock_flag(sk, SOCK_DEAD))
474 sk->sk_data_ready(sk);
475 return 0;
476 }
477 EXPORT_SYMBOL(sock_queue_rcv_skb);
478
479 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
480 {
481 int rc = NET_RX_SUCCESS;
482
483 if (sk_filter(sk, skb))
484 goto discard_and_relse;
485
486 skb->dev = NULL;
487
488 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
489 atomic_inc(&sk->sk_drops);
490 goto discard_and_relse;
491 }
492 if (nested)
493 bh_lock_sock_nested(sk);
494 else
495 bh_lock_sock(sk);
496 if (!sock_owned_by_user(sk)) {
497 /*
498 * trylock + unlock semantics:
499 */
500 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
501
502 rc = sk_backlog_rcv(sk, skb);
503
504 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
505 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
506 bh_unlock_sock(sk);
507 atomic_inc(&sk->sk_drops);
508 goto discard_and_relse;
509 }
510
511 bh_unlock_sock(sk);
512 out:
513 sock_put(sk);
514 return rc;
515 discard_and_relse:
516 kfree_skb(skb);
517 goto out;
518 }
519 EXPORT_SYMBOL(sk_receive_skb);
520
521 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
522 {
523 struct dst_entry *dst = __sk_dst_get(sk);
524
525 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
526 sk_tx_queue_clear(sk);
527 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
528 dst_release(dst);
529 return NULL;
530 }
531
532 return dst;
533 }
534 EXPORT_SYMBOL(__sk_dst_check);
535
536 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
537 {
538 struct dst_entry *dst = sk_dst_get(sk);
539
540 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
541 sk_dst_reset(sk);
542 dst_release(dst);
543 return NULL;
544 }
545
546 return dst;
547 }
548 EXPORT_SYMBOL(sk_dst_check);
549
550 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
551 int optlen)
552 {
553 int ret = -ENOPROTOOPT;
554 #ifdef CONFIG_NETDEVICES
555 struct net *net = sock_net(sk);
556 char devname[IFNAMSIZ];
557 int index;
558
559 /* Sorry... */
560 ret = -EPERM;
561 if (!ns_capable(net->user_ns, CAP_NET_RAW))
562 goto out;
563
564 ret = -EINVAL;
565 if (optlen < 0)
566 goto out;
567
568 /* Bind this socket to a particular device like "eth0",
569 * as specified in the passed interface name. If the
570 * name is "" or the option length is zero the socket
571 * is not bound.
572 */
573 if (optlen > IFNAMSIZ - 1)
574 optlen = IFNAMSIZ - 1;
575 memset(devname, 0, sizeof(devname));
576
577 ret = -EFAULT;
578 if (copy_from_user(devname, optval, optlen))
579 goto out;
580
581 index = 0;
582 if (devname[0] != '\0') {
583 struct net_device *dev;
584
585 rcu_read_lock();
586 dev = dev_get_by_name_rcu(net, devname);
587 if (dev)
588 index = dev->ifindex;
589 rcu_read_unlock();
590 ret = -ENODEV;
591 if (!dev)
592 goto out;
593 }
594
595 lock_sock(sk);
596 sk->sk_bound_dev_if = index;
597 sk_dst_reset(sk);
598 release_sock(sk);
599
600 ret = 0;
601
602 out:
603 #endif
604
605 return ret;
606 }
607
608 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
609 int __user *optlen, int len)
610 {
611 int ret = -ENOPROTOOPT;
612 #ifdef CONFIG_NETDEVICES
613 struct net *net = sock_net(sk);
614 char devname[IFNAMSIZ];
615
616 if (sk->sk_bound_dev_if == 0) {
617 len = 0;
618 goto zero;
619 }
620
621 ret = -EINVAL;
622 if (len < IFNAMSIZ)
623 goto out;
624
625 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
626 if (ret)
627 goto out;
628
629 len = strlen(devname) + 1;
630
631 ret = -EFAULT;
632 if (copy_to_user(optval, devname, len))
633 goto out;
634
635 zero:
636 ret = -EFAULT;
637 if (put_user(len, optlen))
638 goto out;
639
640 ret = 0;
641
642 out:
643 #endif
644
645 return ret;
646 }
647
648 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
649 {
650 if (valbool)
651 sock_set_flag(sk, bit);
652 else
653 sock_reset_flag(sk, bit);
654 }
655
656 /*
657 * This is meant for all protocols to use and covers goings on
658 * at the socket level. Everything here is generic.
659 */
660
661 int sock_setsockopt(struct socket *sock, int level, int optname,
662 char __user *optval, unsigned int optlen)
663 {
664 struct sock *sk = sock->sk;
665 int val;
666 int valbool;
667 struct linger ling;
668 int ret = 0;
669
670 /*
671 * Options without arguments
672 */
673
674 if (optname == SO_BINDTODEVICE)
675 return sock_setbindtodevice(sk, optval, optlen);
676
677 if (optlen < sizeof(int))
678 return -EINVAL;
679
680 if (get_user(val, (int __user *)optval))
681 return -EFAULT;
682
683 valbool = val ? 1 : 0;
684
685 lock_sock(sk);
686
687 switch (optname) {
688 case SO_DEBUG:
689 if (val && !capable(CAP_NET_ADMIN))
690 ret = -EACCES;
691 else
692 sock_valbool_flag(sk, SOCK_DBG, valbool);
693 break;
694 case SO_REUSEADDR:
695 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
696 break;
697 case SO_REUSEPORT:
698 sk->sk_reuseport = valbool;
699 break;
700 case SO_TYPE:
701 case SO_PROTOCOL:
702 case SO_DOMAIN:
703 case SO_ERROR:
704 ret = -ENOPROTOOPT;
705 break;
706 case SO_DONTROUTE:
707 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
708 break;
709 case SO_BROADCAST:
710 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
711 break;
712 case SO_SNDBUF:
713 /* Don't error on this BSD doesn't and if you think
714 * about it this is right. Otherwise apps have to
715 * play 'guess the biggest size' games. RCVBUF/SNDBUF
716 * are treated in BSD as hints
717 */
718 val = min_t(u32, val, sysctl_wmem_max);
719 set_sndbuf:
720 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
721 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
722 /* Wake up sending tasks if we upped the value. */
723 sk->sk_write_space(sk);
724 break;
725
726 case SO_SNDBUFFORCE:
727 if (!capable(CAP_NET_ADMIN)) {
728 ret = -EPERM;
729 break;
730 }
731 goto set_sndbuf;
732
733 case SO_RCVBUF:
734 /* Don't error on this BSD doesn't and if you think
735 * about it this is right. Otherwise apps have to
736 * play 'guess the biggest size' games. RCVBUF/SNDBUF
737 * are treated in BSD as hints
738 */
739 val = min_t(u32, val, sysctl_rmem_max);
740 set_rcvbuf:
741 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
742 /*
743 * We double it on the way in to account for
744 * "struct sk_buff" etc. overhead. Applications
745 * assume that the SO_RCVBUF setting they make will
746 * allow that much actual data to be received on that
747 * socket.
748 *
749 * Applications are unaware that "struct sk_buff" and
750 * other overheads allocate from the receive buffer
751 * during socket buffer allocation.
752 *
753 * And after considering the possible alternatives,
754 * returning the value we actually used in getsockopt
755 * is the most desirable behavior.
756 */
757 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
758 break;
759
760 case SO_RCVBUFFORCE:
761 if (!capable(CAP_NET_ADMIN)) {
762 ret = -EPERM;
763 break;
764 }
765 goto set_rcvbuf;
766
767 case SO_KEEPALIVE:
768 #ifdef CONFIG_INET
769 if (sk->sk_protocol == IPPROTO_TCP &&
770 sk->sk_type == SOCK_STREAM)
771 tcp_set_keepalive(sk, valbool);
772 #endif
773 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
774 break;
775
776 case SO_OOBINLINE:
777 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
778 break;
779
780 case SO_NO_CHECK:
781 sk->sk_no_check_tx = valbool;
782 break;
783
784 case SO_PRIORITY:
785 if ((val >= 0 && val <= 6) ||
786 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
787 sk->sk_priority = val;
788 else
789 ret = -EPERM;
790 break;
791
792 case SO_LINGER:
793 if (optlen < sizeof(ling)) {
794 ret = -EINVAL; /* 1003.1g */
795 break;
796 }
797 if (copy_from_user(&ling, optval, sizeof(ling))) {
798 ret = -EFAULT;
799 break;
800 }
801 if (!ling.l_onoff)
802 sock_reset_flag(sk, SOCK_LINGER);
803 else {
804 #if (BITS_PER_LONG == 32)
805 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
806 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
807 else
808 #endif
809 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
810 sock_set_flag(sk, SOCK_LINGER);
811 }
812 break;
813
814 case SO_BSDCOMPAT:
815 sock_warn_obsolete_bsdism("setsockopt");
816 break;
817
818 case SO_PASSCRED:
819 if (valbool)
820 set_bit(SOCK_PASSCRED, &sock->flags);
821 else
822 clear_bit(SOCK_PASSCRED, &sock->flags);
823 break;
824
825 case SO_TIMESTAMP:
826 case SO_TIMESTAMPNS:
827 if (valbool) {
828 if (optname == SO_TIMESTAMP)
829 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
830 else
831 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
832 sock_set_flag(sk, SOCK_RCVTSTAMP);
833 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
834 } else {
835 sock_reset_flag(sk, SOCK_RCVTSTAMP);
836 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
837 }
838 break;
839
840 case SO_TIMESTAMPING:
841 if (val & ~SOF_TIMESTAMPING_MASK) {
842 ret = -EINVAL;
843 break;
844 }
845
846 if (val & SOF_TIMESTAMPING_OPT_ID &&
847 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
848 if (sk->sk_protocol == IPPROTO_TCP) {
849 if (sk->sk_state != TCP_ESTABLISHED) {
850 ret = -EINVAL;
851 break;
852 }
853 sk->sk_tskey = tcp_sk(sk)->snd_una;
854 } else {
855 sk->sk_tskey = 0;
856 }
857 }
858 sk->sk_tsflags = val;
859 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
860 sock_enable_timestamp(sk,
861 SOCK_TIMESTAMPING_RX_SOFTWARE);
862 else
863 sock_disable_timestamp(sk,
864 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
865 break;
866
867 case SO_RCVLOWAT:
868 if (val < 0)
869 val = INT_MAX;
870 sk->sk_rcvlowat = val ? : 1;
871 break;
872
873 case SO_RCVTIMEO:
874 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
875 break;
876
877 case SO_SNDTIMEO:
878 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
879 break;
880
881 case SO_ATTACH_FILTER:
882 ret = -EINVAL;
883 if (optlen == sizeof(struct sock_fprog)) {
884 struct sock_fprog fprog;
885
886 ret = -EFAULT;
887 if (copy_from_user(&fprog, optval, sizeof(fprog)))
888 break;
889
890 ret = sk_attach_filter(&fprog, sk);
891 }
892 break;
893
894 case SO_ATTACH_BPF:
895 ret = -EINVAL;
896 if (optlen == sizeof(u32)) {
897 u32 ufd;
898
899 ret = -EFAULT;
900 if (copy_from_user(&ufd, optval, sizeof(ufd)))
901 break;
902
903 ret = sk_attach_bpf(ufd, sk);
904 }
905 break;
906
907 case SO_DETACH_FILTER:
908 ret = sk_detach_filter(sk);
909 break;
910
911 case SO_LOCK_FILTER:
912 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
913 ret = -EPERM;
914 else
915 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
916 break;
917
918 case SO_PASSSEC:
919 if (valbool)
920 set_bit(SOCK_PASSSEC, &sock->flags);
921 else
922 clear_bit(SOCK_PASSSEC, &sock->flags);
923 break;
924 case SO_MARK:
925 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
926 ret = -EPERM;
927 else
928 sk->sk_mark = val;
929 break;
930
931 /* We implement the SO_SNDLOWAT etc to
932 not be settable (1003.1g 5.3) */
933 case SO_RXQ_OVFL:
934 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
935 break;
936
937 case SO_WIFI_STATUS:
938 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
939 break;
940
941 case SO_PEEK_OFF:
942 if (sock->ops->set_peek_off)
943 ret = sock->ops->set_peek_off(sk, val);
944 else
945 ret = -EOPNOTSUPP;
946 break;
947
948 case SO_NOFCS:
949 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
950 break;
951
952 case SO_SELECT_ERR_QUEUE:
953 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
954 break;
955
956 #ifdef CONFIG_NET_RX_BUSY_POLL
957 case SO_BUSY_POLL:
958 /* allow unprivileged users to decrease the value */
959 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
960 ret = -EPERM;
961 else {
962 if (val < 0)
963 ret = -EINVAL;
964 else
965 sk->sk_ll_usec = val;
966 }
967 break;
968 #endif
969
970 case SO_MAX_PACING_RATE:
971 sk->sk_max_pacing_rate = val;
972 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
973 sk->sk_max_pacing_rate);
974 break;
975
976 default:
977 ret = -ENOPROTOOPT;
978 break;
979 }
980 release_sock(sk);
981 return ret;
982 }
983 EXPORT_SYMBOL(sock_setsockopt);
984
985
986 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
987 struct ucred *ucred)
988 {
989 ucred->pid = pid_vnr(pid);
990 ucred->uid = ucred->gid = -1;
991 if (cred) {
992 struct user_namespace *current_ns = current_user_ns();
993
994 ucred->uid = from_kuid_munged(current_ns, cred->euid);
995 ucred->gid = from_kgid_munged(current_ns, cred->egid);
996 }
997 }
998
999 int sock_getsockopt(struct socket *sock, int level, int optname,
1000 char __user *optval, int __user *optlen)
1001 {
1002 struct sock *sk = sock->sk;
1003
1004 union {
1005 int val;
1006 struct linger ling;
1007 struct timeval tm;
1008 } v;
1009
1010 int lv = sizeof(int);
1011 int len;
1012
1013 if (get_user(len, optlen))
1014 return -EFAULT;
1015 if (len < 0)
1016 return -EINVAL;
1017
1018 memset(&v, 0, sizeof(v));
1019
1020 switch (optname) {
1021 case SO_DEBUG:
1022 v.val = sock_flag(sk, SOCK_DBG);
1023 break;
1024
1025 case SO_DONTROUTE:
1026 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1027 break;
1028
1029 case SO_BROADCAST:
1030 v.val = sock_flag(sk, SOCK_BROADCAST);
1031 break;
1032
1033 case SO_SNDBUF:
1034 v.val = sk->sk_sndbuf;
1035 break;
1036
1037 case SO_RCVBUF:
1038 v.val = sk->sk_rcvbuf;
1039 break;
1040
1041 case SO_REUSEADDR:
1042 v.val = sk->sk_reuse;
1043 break;
1044
1045 case SO_REUSEPORT:
1046 v.val = sk->sk_reuseport;
1047 break;
1048
1049 case SO_KEEPALIVE:
1050 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1051 break;
1052
1053 case SO_TYPE:
1054 v.val = sk->sk_type;
1055 break;
1056
1057 case SO_PROTOCOL:
1058 v.val = sk->sk_protocol;
1059 break;
1060
1061 case SO_DOMAIN:
1062 v.val = sk->sk_family;
1063 break;
1064
1065 case SO_ERROR:
1066 v.val = -sock_error(sk);
1067 if (v.val == 0)
1068 v.val = xchg(&sk->sk_err_soft, 0);
1069 break;
1070
1071 case SO_OOBINLINE:
1072 v.val = sock_flag(sk, SOCK_URGINLINE);
1073 break;
1074
1075 case SO_NO_CHECK:
1076 v.val = sk->sk_no_check_tx;
1077 break;
1078
1079 case SO_PRIORITY:
1080 v.val = sk->sk_priority;
1081 break;
1082
1083 case SO_LINGER:
1084 lv = sizeof(v.ling);
1085 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1086 v.ling.l_linger = sk->sk_lingertime / HZ;
1087 break;
1088
1089 case SO_BSDCOMPAT:
1090 sock_warn_obsolete_bsdism("getsockopt");
1091 break;
1092
1093 case SO_TIMESTAMP:
1094 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1095 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1096 break;
1097
1098 case SO_TIMESTAMPNS:
1099 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1100 break;
1101
1102 case SO_TIMESTAMPING:
1103 v.val = sk->sk_tsflags;
1104 break;
1105
1106 case SO_RCVTIMEO:
1107 lv = sizeof(struct timeval);
1108 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1109 v.tm.tv_sec = 0;
1110 v.tm.tv_usec = 0;
1111 } else {
1112 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1113 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1114 }
1115 break;
1116
1117 case SO_SNDTIMEO:
1118 lv = sizeof(struct timeval);
1119 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1120 v.tm.tv_sec = 0;
1121 v.tm.tv_usec = 0;
1122 } else {
1123 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1124 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1125 }
1126 break;
1127
1128 case SO_RCVLOWAT:
1129 v.val = sk->sk_rcvlowat;
1130 break;
1131
1132 case SO_SNDLOWAT:
1133 v.val = 1;
1134 break;
1135
1136 case SO_PASSCRED:
1137 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1138 break;
1139
1140 case SO_PEERCRED:
1141 {
1142 struct ucred peercred;
1143 if (len > sizeof(peercred))
1144 len = sizeof(peercred);
1145 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1146 if (copy_to_user(optval, &peercred, len))
1147 return -EFAULT;
1148 goto lenout;
1149 }
1150
1151 case SO_PEERNAME:
1152 {
1153 char address[128];
1154
1155 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1156 return -ENOTCONN;
1157 if (lv < len)
1158 return -EINVAL;
1159 if (copy_to_user(optval, address, len))
1160 return -EFAULT;
1161 goto lenout;
1162 }
1163
1164 /* Dubious BSD thing... Probably nobody even uses it, but
1165 * the UNIX standard wants it for whatever reason... -DaveM
1166 */
1167 case SO_ACCEPTCONN:
1168 v.val = sk->sk_state == TCP_LISTEN;
1169 break;
1170
1171 case SO_PASSSEC:
1172 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1173 break;
1174
1175 case SO_PEERSEC:
1176 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1177
1178 case SO_MARK:
1179 v.val = sk->sk_mark;
1180 break;
1181
1182 case SO_RXQ_OVFL:
1183 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1184 break;
1185
1186 case SO_WIFI_STATUS:
1187 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1188 break;
1189
1190 case SO_PEEK_OFF:
1191 if (!sock->ops->set_peek_off)
1192 return -EOPNOTSUPP;
1193
1194 v.val = sk->sk_peek_off;
1195 break;
1196 case SO_NOFCS:
1197 v.val = sock_flag(sk, SOCK_NOFCS);
1198 break;
1199
1200 case SO_BINDTODEVICE:
1201 return sock_getbindtodevice(sk, optval, optlen, len);
1202
1203 case SO_GET_FILTER:
1204 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1205 if (len < 0)
1206 return len;
1207
1208 goto lenout;
1209
1210 case SO_LOCK_FILTER:
1211 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1212 break;
1213
1214 case SO_BPF_EXTENSIONS:
1215 v.val = bpf_tell_extensions();
1216 break;
1217
1218 case SO_SELECT_ERR_QUEUE:
1219 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1220 break;
1221
1222 #ifdef CONFIG_NET_RX_BUSY_POLL
1223 case SO_BUSY_POLL:
1224 v.val = sk->sk_ll_usec;
1225 break;
1226 #endif
1227
1228 case SO_MAX_PACING_RATE:
1229 v.val = sk->sk_max_pacing_rate;
1230 break;
1231
1232 case SO_INCOMING_CPU:
1233 v.val = sk->sk_incoming_cpu;
1234 break;
1235
1236 default:
1237 return -ENOPROTOOPT;
1238 }
1239
1240 if (len > lv)
1241 len = lv;
1242 if (copy_to_user(optval, &v, len))
1243 return -EFAULT;
1244 lenout:
1245 if (put_user(len, optlen))
1246 return -EFAULT;
1247 return 0;
1248 }
1249
1250 /*
1251 * Initialize an sk_lock.
1252 *
1253 * (We also register the sk_lock with the lock validator.)
1254 */
1255 static inline void sock_lock_init(struct sock *sk)
1256 {
1257 sock_lock_init_class_and_name(sk,
1258 af_family_slock_key_strings[sk->sk_family],
1259 af_family_slock_keys + sk->sk_family,
1260 af_family_key_strings[sk->sk_family],
1261 af_family_keys + sk->sk_family);
1262 }
1263
1264 /*
1265 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1266 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1267 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1268 */
1269 static void sock_copy(struct sock *nsk, const struct sock *osk)
1270 {
1271 #ifdef CONFIG_SECURITY_NETWORK
1272 void *sptr = nsk->sk_security;
1273 #endif
1274 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1275
1276 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1277 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1278
1279 #ifdef CONFIG_SECURITY_NETWORK
1280 nsk->sk_security = sptr;
1281 security_sk_clone(osk, nsk);
1282 #endif
1283 }
1284
1285 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1286 {
1287 unsigned long nulls1, nulls2;
1288
1289 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1290 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1291 if (nulls1 > nulls2)
1292 swap(nulls1, nulls2);
1293
1294 if (nulls1 != 0)
1295 memset((char *)sk, 0, nulls1);
1296 memset((char *)sk + nulls1 + sizeof(void *), 0,
1297 nulls2 - nulls1 - sizeof(void *));
1298 memset((char *)sk + nulls2 + sizeof(void *), 0,
1299 size - nulls2 - sizeof(void *));
1300 }
1301 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1302
1303 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1304 int family)
1305 {
1306 struct sock *sk;
1307 struct kmem_cache *slab;
1308
1309 slab = prot->slab;
1310 if (slab != NULL) {
1311 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1312 if (!sk)
1313 return sk;
1314 if (priority & __GFP_ZERO) {
1315 if (prot->clear_sk)
1316 prot->clear_sk(sk, prot->obj_size);
1317 else
1318 sk_prot_clear_nulls(sk, prot->obj_size);
1319 }
1320 } else
1321 sk = kmalloc(prot->obj_size, priority);
1322
1323 if (sk != NULL) {
1324 kmemcheck_annotate_bitfield(sk, flags);
1325
1326 if (security_sk_alloc(sk, family, priority))
1327 goto out_free;
1328
1329 if (!try_module_get(prot->owner))
1330 goto out_free_sec;
1331 sk_tx_queue_clear(sk);
1332 }
1333
1334 return sk;
1335
1336 out_free_sec:
1337 security_sk_free(sk);
1338 out_free:
1339 if (slab != NULL)
1340 kmem_cache_free(slab, sk);
1341 else
1342 kfree(sk);
1343 return NULL;
1344 }
1345
1346 static void sk_prot_free(struct proto *prot, struct sock *sk)
1347 {
1348 struct kmem_cache *slab;
1349 struct module *owner;
1350
1351 owner = prot->owner;
1352 slab = prot->slab;
1353
1354 security_sk_free(sk);
1355 if (slab != NULL)
1356 kmem_cache_free(slab, sk);
1357 else
1358 kfree(sk);
1359 module_put(owner);
1360 }
1361
1362 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
1363 void sock_update_netprioidx(struct sock *sk)
1364 {
1365 if (in_interrupt())
1366 return;
1367
1368 sk->sk_cgrp_prioidx = task_netprioidx(current);
1369 }
1370 EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1371 #endif
1372
1373 /**
1374 * sk_alloc - All socket objects are allocated here
1375 * @net: the applicable net namespace
1376 * @family: protocol family
1377 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1378 * @prot: struct proto associated with this new sock instance
1379 */
1380 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1381 struct proto *prot)
1382 {
1383 struct sock *sk;
1384
1385 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1386 if (sk) {
1387 sk->sk_family = family;
1388 /*
1389 * See comment in struct sock definition to understand
1390 * why we need sk_prot_creator -acme
1391 */
1392 sk->sk_prot = sk->sk_prot_creator = prot;
1393 sock_lock_init(sk);
1394 sock_net_set(sk, get_net(net));
1395 atomic_set(&sk->sk_wmem_alloc, 1);
1396
1397 sock_update_classid(sk);
1398 sock_update_netprioidx(sk);
1399 }
1400
1401 return sk;
1402 }
1403 EXPORT_SYMBOL(sk_alloc);
1404
1405 static void __sk_free(struct sock *sk)
1406 {
1407 struct sk_filter *filter;
1408
1409 if (sk->sk_destruct)
1410 sk->sk_destruct(sk);
1411
1412 filter = rcu_dereference_check(sk->sk_filter,
1413 atomic_read(&sk->sk_wmem_alloc) == 0);
1414 if (filter) {
1415 sk_filter_uncharge(sk, filter);
1416 RCU_INIT_POINTER(sk->sk_filter, NULL);
1417 }
1418
1419 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1420
1421 if (atomic_read(&sk->sk_omem_alloc))
1422 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1423 __func__, atomic_read(&sk->sk_omem_alloc));
1424
1425 if (sk->sk_peer_cred)
1426 put_cred(sk->sk_peer_cred);
1427 put_pid(sk->sk_peer_pid);
1428 put_net(sock_net(sk));
1429 sk_prot_free(sk->sk_prot_creator, sk);
1430 }
1431
1432 void sk_free(struct sock *sk)
1433 {
1434 /*
1435 * We subtract one from sk_wmem_alloc and can know if
1436 * some packets are still in some tx queue.
1437 * If not null, sock_wfree() will call __sk_free(sk) later
1438 */
1439 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1440 __sk_free(sk);
1441 }
1442 EXPORT_SYMBOL(sk_free);
1443
1444 /*
1445 * Last sock_put should drop reference to sk->sk_net. It has already
1446 * been dropped in sk_change_net. Taking reference to stopping namespace
1447 * is not an option.
1448 * Take reference to a socket to remove it from hash _alive_ and after that
1449 * destroy it in the context of init_net.
1450 */
1451 void sk_release_kernel(struct sock *sk)
1452 {
1453 if (sk == NULL || sk->sk_socket == NULL)
1454 return;
1455
1456 sock_hold(sk);
1457 sock_release(sk->sk_socket);
1458 release_net(sock_net(sk));
1459 sock_net_set(sk, get_net(&init_net));
1460 sock_put(sk);
1461 }
1462 EXPORT_SYMBOL(sk_release_kernel);
1463
1464 static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1465 {
1466 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1467 sock_update_memcg(newsk);
1468 }
1469
1470 /**
1471 * sk_clone_lock - clone a socket, and lock its clone
1472 * @sk: the socket to clone
1473 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1474 *
1475 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1476 */
1477 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1478 {
1479 struct sock *newsk;
1480 bool is_charged = true;
1481
1482 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1483 if (newsk != NULL) {
1484 struct sk_filter *filter;
1485
1486 sock_copy(newsk, sk);
1487
1488 /* SANITY */
1489 get_net(sock_net(newsk));
1490 sk_node_init(&newsk->sk_node);
1491 sock_lock_init(newsk);
1492 bh_lock_sock(newsk);
1493 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1494 newsk->sk_backlog.len = 0;
1495
1496 atomic_set(&newsk->sk_rmem_alloc, 0);
1497 /*
1498 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1499 */
1500 atomic_set(&newsk->sk_wmem_alloc, 1);
1501 atomic_set(&newsk->sk_omem_alloc, 0);
1502 skb_queue_head_init(&newsk->sk_receive_queue);
1503 skb_queue_head_init(&newsk->sk_write_queue);
1504
1505 spin_lock_init(&newsk->sk_dst_lock);
1506 rwlock_init(&newsk->sk_callback_lock);
1507 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1508 af_callback_keys + newsk->sk_family,
1509 af_family_clock_key_strings[newsk->sk_family]);
1510
1511 newsk->sk_dst_cache = NULL;
1512 newsk->sk_wmem_queued = 0;
1513 newsk->sk_forward_alloc = 0;
1514 newsk->sk_send_head = NULL;
1515 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1516
1517 sock_reset_flag(newsk, SOCK_DONE);
1518 skb_queue_head_init(&newsk->sk_error_queue);
1519
1520 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1521 if (filter != NULL)
1522 /* though it's an empty new sock, the charging may fail
1523 * if sysctl_optmem_max was changed between creation of
1524 * original socket and cloning
1525 */
1526 is_charged = sk_filter_charge(newsk, filter);
1527
1528 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) {
1529 /* It is still raw copy of parent, so invalidate
1530 * destructor and make plain sk_free() */
1531 newsk->sk_destruct = NULL;
1532 bh_unlock_sock(newsk);
1533 sk_free(newsk);
1534 newsk = NULL;
1535 goto out;
1536 }
1537
1538 newsk->sk_err = 0;
1539 newsk->sk_priority = 0;
1540 newsk->sk_incoming_cpu = raw_smp_processor_id();
1541 /*
1542 * Before updating sk_refcnt, we must commit prior changes to memory
1543 * (Documentation/RCU/rculist_nulls.txt for details)
1544 */
1545 smp_wmb();
1546 atomic_set(&newsk->sk_refcnt, 2);
1547
1548 /*
1549 * Increment the counter in the same struct proto as the master
1550 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1551 * is the same as sk->sk_prot->socks, as this field was copied
1552 * with memcpy).
1553 *
1554 * This _changes_ the previous behaviour, where
1555 * tcp_create_openreq_child always was incrementing the
1556 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1557 * to be taken into account in all callers. -acme
1558 */
1559 sk_refcnt_debug_inc(newsk);
1560 sk_set_socket(newsk, NULL);
1561 newsk->sk_wq = NULL;
1562
1563 sk_update_clone(sk, newsk);
1564
1565 if (newsk->sk_prot->sockets_allocated)
1566 sk_sockets_allocated_inc(newsk);
1567
1568 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1569 net_enable_timestamp();
1570 }
1571 out:
1572 return newsk;
1573 }
1574 EXPORT_SYMBOL_GPL(sk_clone_lock);
1575
1576 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1577 {
1578 __sk_dst_set(sk, dst);
1579 sk->sk_route_caps = dst->dev->features;
1580 if (sk->sk_route_caps & NETIF_F_GSO)
1581 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1582 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1583 if (sk_can_gso(sk)) {
1584 if (dst->header_len) {
1585 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1586 } else {
1587 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1588 sk->sk_gso_max_size = dst->dev->gso_max_size;
1589 sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1590 }
1591 }
1592 }
1593 EXPORT_SYMBOL_GPL(sk_setup_caps);
1594
1595 /*
1596 * Simple resource managers for sockets.
1597 */
1598
1599
1600 /*
1601 * Write buffer destructor automatically called from kfree_skb.
1602 */
1603 void sock_wfree(struct sk_buff *skb)
1604 {
1605 struct sock *sk = skb->sk;
1606 unsigned int len = skb->truesize;
1607
1608 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1609 /*
1610 * Keep a reference on sk_wmem_alloc, this will be released
1611 * after sk_write_space() call
1612 */
1613 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1614 sk->sk_write_space(sk);
1615 len = 1;
1616 }
1617 /*
1618 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1619 * could not do because of in-flight packets
1620 */
1621 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1622 __sk_free(sk);
1623 }
1624 EXPORT_SYMBOL(sock_wfree);
1625
1626 void skb_orphan_partial(struct sk_buff *skb)
1627 {
1628 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1629 * so we do not completely orphan skb, but transfert all
1630 * accounted bytes but one, to avoid unexpected reorders.
1631 */
1632 if (skb->destructor == sock_wfree
1633 #ifdef CONFIG_INET
1634 || skb->destructor == tcp_wfree
1635 #endif
1636 ) {
1637 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1638 skb->truesize = 1;
1639 } else {
1640 skb_orphan(skb);
1641 }
1642 }
1643 EXPORT_SYMBOL(skb_orphan_partial);
1644
1645 /*
1646 * Read buffer destructor automatically called from kfree_skb.
1647 */
1648 void sock_rfree(struct sk_buff *skb)
1649 {
1650 struct sock *sk = skb->sk;
1651 unsigned int len = skb->truesize;
1652
1653 atomic_sub(len, &sk->sk_rmem_alloc);
1654 sk_mem_uncharge(sk, len);
1655 }
1656 EXPORT_SYMBOL(sock_rfree);
1657
1658 /*
1659 * Buffer destructor for skbs that are not used directly in read or write
1660 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1661 */
1662 void sock_efree(struct sk_buff *skb)
1663 {
1664 sock_put(skb->sk);
1665 }
1666 EXPORT_SYMBOL(sock_efree);
1667
1668 #ifdef CONFIG_INET
1669 void sock_edemux(struct sk_buff *skb)
1670 {
1671 struct sock *sk = skb->sk;
1672
1673 if (sk->sk_state == TCP_TIME_WAIT)
1674 inet_twsk_put(inet_twsk(sk));
1675 else
1676 sock_put(sk);
1677 }
1678 EXPORT_SYMBOL(sock_edemux);
1679 #endif
1680
1681 kuid_t sock_i_uid(struct sock *sk)
1682 {
1683 kuid_t uid;
1684
1685 read_lock_bh(&sk->sk_callback_lock);
1686 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1687 read_unlock_bh(&sk->sk_callback_lock);
1688 return uid;
1689 }
1690 EXPORT_SYMBOL(sock_i_uid);
1691
1692 unsigned long sock_i_ino(struct sock *sk)
1693 {
1694 unsigned long ino;
1695
1696 read_lock_bh(&sk->sk_callback_lock);
1697 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1698 read_unlock_bh(&sk->sk_callback_lock);
1699 return ino;
1700 }
1701 EXPORT_SYMBOL(sock_i_ino);
1702
1703 /*
1704 * Allocate a skb from the socket's send buffer.
1705 */
1706 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1707 gfp_t priority)
1708 {
1709 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1710 struct sk_buff *skb = alloc_skb(size, priority);
1711 if (skb) {
1712 skb_set_owner_w(skb, sk);
1713 return skb;
1714 }
1715 }
1716 return NULL;
1717 }
1718 EXPORT_SYMBOL(sock_wmalloc);
1719
1720 /*
1721 * Allocate a memory block from the socket's option memory buffer.
1722 */
1723 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1724 {
1725 if ((unsigned int)size <= sysctl_optmem_max &&
1726 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1727 void *mem;
1728 /* First do the add, to avoid the race if kmalloc
1729 * might sleep.
1730 */
1731 atomic_add(size, &sk->sk_omem_alloc);
1732 mem = kmalloc(size, priority);
1733 if (mem)
1734 return mem;
1735 atomic_sub(size, &sk->sk_omem_alloc);
1736 }
1737 return NULL;
1738 }
1739 EXPORT_SYMBOL(sock_kmalloc);
1740
1741 /* Free an option memory block. Note, we actually want the inline
1742 * here as this allows gcc to detect the nullify and fold away the
1743 * condition entirely.
1744 */
1745 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1746 const bool nullify)
1747 {
1748 if (WARN_ON_ONCE(!mem))
1749 return;
1750 if (nullify)
1751 kzfree(mem);
1752 else
1753 kfree(mem);
1754 atomic_sub(size, &sk->sk_omem_alloc);
1755 }
1756
1757 void sock_kfree_s(struct sock *sk, void *mem, int size)
1758 {
1759 __sock_kfree_s(sk, mem, size, false);
1760 }
1761 EXPORT_SYMBOL(sock_kfree_s);
1762
1763 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1764 {
1765 __sock_kfree_s(sk, mem, size, true);
1766 }
1767 EXPORT_SYMBOL(sock_kzfree_s);
1768
1769 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1770 I think, these locks should be removed for datagram sockets.
1771 */
1772 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1773 {
1774 DEFINE_WAIT(wait);
1775
1776 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1777 for (;;) {
1778 if (!timeo)
1779 break;
1780 if (signal_pending(current))
1781 break;
1782 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1783 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1784 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1785 break;
1786 if (sk->sk_shutdown & SEND_SHUTDOWN)
1787 break;
1788 if (sk->sk_err)
1789 break;
1790 timeo = schedule_timeout(timeo);
1791 }
1792 finish_wait(sk_sleep(sk), &wait);
1793 return timeo;
1794 }
1795
1796
1797 /*
1798 * Generic send/receive buffer handlers
1799 */
1800
1801 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1802 unsigned long data_len, int noblock,
1803 int *errcode, int max_page_order)
1804 {
1805 struct sk_buff *skb;
1806 long timeo;
1807 int err;
1808
1809 timeo = sock_sndtimeo(sk, noblock);
1810 for (;;) {
1811 err = sock_error(sk);
1812 if (err != 0)
1813 goto failure;
1814
1815 err = -EPIPE;
1816 if (sk->sk_shutdown & SEND_SHUTDOWN)
1817 goto failure;
1818
1819 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1820 break;
1821
1822 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1823 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1824 err = -EAGAIN;
1825 if (!timeo)
1826 goto failure;
1827 if (signal_pending(current))
1828 goto interrupted;
1829 timeo = sock_wait_for_wmem(sk, timeo);
1830 }
1831 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1832 errcode, sk->sk_allocation);
1833 if (skb)
1834 skb_set_owner_w(skb, sk);
1835 return skb;
1836
1837 interrupted:
1838 err = sock_intr_errno(timeo);
1839 failure:
1840 *errcode = err;
1841 return NULL;
1842 }
1843 EXPORT_SYMBOL(sock_alloc_send_pskb);
1844
1845 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1846 int noblock, int *errcode)
1847 {
1848 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1849 }
1850 EXPORT_SYMBOL(sock_alloc_send_skb);
1851
1852 /* On 32bit arches, an skb frag is limited to 2^15 */
1853 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1854
1855 /**
1856 * skb_page_frag_refill - check that a page_frag contains enough room
1857 * @sz: minimum size of the fragment we want to get
1858 * @pfrag: pointer to page_frag
1859 * @gfp: priority for memory allocation
1860 *
1861 * Note: While this allocator tries to use high order pages, there is
1862 * no guarantee that allocations succeed. Therefore, @sz MUST be
1863 * less or equal than PAGE_SIZE.
1864 */
1865 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1866 {
1867 if (pfrag->page) {
1868 if (atomic_read(&pfrag->page->_count) == 1) {
1869 pfrag->offset = 0;
1870 return true;
1871 }
1872 if (pfrag->offset + sz <= pfrag->size)
1873 return true;
1874 put_page(pfrag->page);
1875 }
1876
1877 pfrag->offset = 0;
1878 if (SKB_FRAG_PAGE_ORDER) {
1879 pfrag->page = alloc_pages(gfp | __GFP_COMP |
1880 __GFP_NOWARN | __GFP_NORETRY,
1881 SKB_FRAG_PAGE_ORDER);
1882 if (likely(pfrag->page)) {
1883 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1884 return true;
1885 }
1886 }
1887 pfrag->page = alloc_page(gfp);
1888 if (likely(pfrag->page)) {
1889 pfrag->size = PAGE_SIZE;
1890 return true;
1891 }
1892 return false;
1893 }
1894 EXPORT_SYMBOL(skb_page_frag_refill);
1895
1896 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1897 {
1898 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1899 return true;
1900
1901 sk_enter_memory_pressure(sk);
1902 sk_stream_moderate_sndbuf(sk);
1903 return false;
1904 }
1905 EXPORT_SYMBOL(sk_page_frag_refill);
1906
1907 static void __lock_sock(struct sock *sk)
1908 __releases(&sk->sk_lock.slock)
1909 __acquires(&sk->sk_lock.slock)
1910 {
1911 DEFINE_WAIT(wait);
1912
1913 for (;;) {
1914 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1915 TASK_UNINTERRUPTIBLE);
1916 spin_unlock_bh(&sk->sk_lock.slock);
1917 schedule();
1918 spin_lock_bh(&sk->sk_lock.slock);
1919 if (!sock_owned_by_user(sk))
1920 break;
1921 }
1922 finish_wait(&sk->sk_lock.wq, &wait);
1923 }
1924
1925 static void __release_sock(struct sock *sk)
1926 __releases(&sk->sk_lock.slock)
1927 __acquires(&sk->sk_lock.slock)
1928 {
1929 struct sk_buff *skb = sk->sk_backlog.head;
1930
1931 do {
1932 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1933 bh_unlock_sock(sk);
1934
1935 do {
1936 struct sk_buff *next = skb->next;
1937
1938 prefetch(next);
1939 WARN_ON_ONCE(skb_dst_is_noref(skb));
1940 skb->next = NULL;
1941 sk_backlog_rcv(sk, skb);
1942
1943 /*
1944 * We are in process context here with softirqs
1945 * disabled, use cond_resched_softirq() to preempt.
1946 * This is safe to do because we've taken the backlog
1947 * queue private:
1948 */
1949 cond_resched_softirq();
1950
1951 skb = next;
1952 } while (skb != NULL);
1953
1954 bh_lock_sock(sk);
1955 } while ((skb = sk->sk_backlog.head) != NULL);
1956
1957 /*
1958 * Doing the zeroing here guarantee we can not loop forever
1959 * while a wild producer attempts to flood us.
1960 */
1961 sk->sk_backlog.len = 0;
1962 }
1963
1964 /**
1965 * sk_wait_data - wait for data to arrive at sk_receive_queue
1966 * @sk: sock to wait on
1967 * @timeo: for how long
1968 *
1969 * Now socket state including sk->sk_err is changed only under lock,
1970 * hence we may omit checks after joining wait queue.
1971 * We check receive queue before schedule() only as optimization;
1972 * it is very likely that release_sock() added new data.
1973 */
1974 int sk_wait_data(struct sock *sk, long *timeo)
1975 {
1976 int rc;
1977 DEFINE_WAIT(wait);
1978
1979 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1980 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1981 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1982 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1983 finish_wait(sk_sleep(sk), &wait);
1984 return rc;
1985 }
1986 EXPORT_SYMBOL(sk_wait_data);
1987
1988 /**
1989 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1990 * @sk: socket
1991 * @size: memory size to allocate
1992 * @kind: allocation type
1993 *
1994 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1995 * rmem allocation. This function assumes that protocols which have
1996 * memory_pressure use sk_wmem_queued as write buffer accounting.
1997 */
1998 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1999 {
2000 struct proto *prot = sk->sk_prot;
2001 int amt = sk_mem_pages(size);
2002 long allocated;
2003 int parent_status = UNDER_LIMIT;
2004
2005 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2006
2007 allocated = sk_memory_allocated_add(sk, amt, &parent_status);
2008
2009 /* Under limit. */
2010 if (parent_status == UNDER_LIMIT &&
2011 allocated <= sk_prot_mem_limits(sk, 0)) {
2012 sk_leave_memory_pressure(sk);
2013 return 1;
2014 }
2015
2016 /* Under pressure. (we or our parents) */
2017 if ((parent_status > SOFT_LIMIT) ||
2018 allocated > sk_prot_mem_limits(sk, 1))
2019 sk_enter_memory_pressure(sk);
2020
2021 /* Over hard limit (we or our parents) */
2022 if ((parent_status == OVER_LIMIT) ||
2023 (allocated > sk_prot_mem_limits(sk, 2)))
2024 goto suppress_allocation;
2025
2026 /* guarantee minimum buffer size under pressure */
2027 if (kind == SK_MEM_RECV) {
2028 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2029 return 1;
2030
2031 } else { /* SK_MEM_SEND */
2032 if (sk->sk_type == SOCK_STREAM) {
2033 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2034 return 1;
2035 } else if (atomic_read(&sk->sk_wmem_alloc) <
2036 prot->sysctl_wmem[0])
2037 return 1;
2038 }
2039
2040 if (sk_has_memory_pressure(sk)) {
2041 int alloc;
2042
2043 if (!sk_under_memory_pressure(sk))
2044 return 1;
2045 alloc = sk_sockets_allocated_read_positive(sk);
2046 if (sk_prot_mem_limits(sk, 2) > alloc *
2047 sk_mem_pages(sk->sk_wmem_queued +
2048 atomic_read(&sk->sk_rmem_alloc) +
2049 sk->sk_forward_alloc))
2050 return 1;
2051 }
2052
2053 suppress_allocation:
2054
2055 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2056 sk_stream_moderate_sndbuf(sk);
2057
2058 /* Fail only if socket is _under_ its sndbuf.
2059 * In this case we cannot block, so that we have to fail.
2060 */
2061 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2062 return 1;
2063 }
2064
2065 trace_sock_exceed_buf_limit(sk, prot, allocated);
2066
2067 /* Alas. Undo changes. */
2068 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2069
2070 sk_memory_allocated_sub(sk, amt);
2071
2072 return 0;
2073 }
2074 EXPORT_SYMBOL(__sk_mem_schedule);
2075
2076 /**
2077 * __sk_reclaim - reclaim memory_allocated
2078 * @sk: socket
2079 */
2080 void __sk_mem_reclaim(struct sock *sk)
2081 {
2082 sk_memory_allocated_sub(sk,
2083 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
2084 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
2085
2086 if (sk_under_memory_pressure(sk) &&
2087 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2088 sk_leave_memory_pressure(sk);
2089 }
2090 EXPORT_SYMBOL(__sk_mem_reclaim);
2091
2092
2093 /*
2094 * Set of default routines for initialising struct proto_ops when
2095 * the protocol does not support a particular function. In certain
2096 * cases where it makes no sense for a protocol to have a "do nothing"
2097 * function, some default processing is provided.
2098 */
2099
2100 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2101 {
2102 return -EOPNOTSUPP;
2103 }
2104 EXPORT_SYMBOL(sock_no_bind);
2105
2106 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2107 int len, int flags)
2108 {
2109 return -EOPNOTSUPP;
2110 }
2111 EXPORT_SYMBOL(sock_no_connect);
2112
2113 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2114 {
2115 return -EOPNOTSUPP;
2116 }
2117 EXPORT_SYMBOL(sock_no_socketpair);
2118
2119 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2120 {
2121 return -EOPNOTSUPP;
2122 }
2123 EXPORT_SYMBOL(sock_no_accept);
2124
2125 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2126 int *len, int peer)
2127 {
2128 return -EOPNOTSUPP;
2129 }
2130 EXPORT_SYMBOL(sock_no_getname);
2131
2132 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2133 {
2134 return 0;
2135 }
2136 EXPORT_SYMBOL(sock_no_poll);
2137
2138 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2139 {
2140 return -EOPNOTSUPP;
2141 }
2142 EXPORT_SYMBOL(sock_no_ioctl);
2143
2144 int sock_no_listen(struct socket *sock, int backlog)
2145 {
2146 return -EOPNOTSUPP;
2147 }
2148 EXPORT_SYMBOL(sock_no_listen);
2149
2150 int sock_no_shutdown(struct socket *sock, int how)
2151 {
2152 return -EOPNOTSUPP;
2153 }
2154 EXPORT_SYMBOL(sock_no_shutdown);
2155
2156 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2157 char __user *optval, unsigned int optlen)
2158 {
2159 return -EOPNOTSUPP;
2160 }
2161 EXPORT_SYMBOL(sock_no_setsockopt);
2162
2163 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2164 char __user *optval, int __user *optlen)
2165 {
2166 return -EOPNOTSUPP;
2167 }
2168 EXPORT_SYMBOL(sock_no_getsockopt);
2169
2170 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2171 size_t len)
2172 {
2173 return -EOPNOTSUPP;
2174 }
2175 EXPORT_SYMBOL(sock_no_sendmsg);
2176
2177 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2178 size_t len, int flags)
2179 {
2180 return -EOPNOTSUPP;
2181 }
2182 EXPORT_SYMBOL(sock_no_recvmsg);
2183
2184 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2185 {
2186 /* Mirror missing mmap method error code */
2187 return -ENODEV;
2188 }
2189 EXPORT_SYMBOL(sock_no_mmap);
2190
2191 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2192 {
2193 ssize_t res;
2194 struct msghdr msg = {.msg_flags = flags};
2195 struct kvec iov;
2196 char *kaddr = kmap(page);
2197 iov.iov_base = kaddr + offset;
2198 iov.iov_len = size;
2199 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2200 kunmap(page);
2201 return res;
2202 }
2203 EXPORT_SYMBOL(sock_no_sendpage);
2204
2205 /*
2206 * Default Socket Callbacks
2207 */
2208
2209 static void sock_def_wakeup(struct sock *sk)
2210 {
2211 struct socket_wq *wq;
2212
2213 rcu_read_lock();
2214 wq = rcu_dereference(sk->sk_wq);
2215 if (wq_has_sleeper(wq))
2216 wake_up_interruptible_all(&wq->wait);
2217 rcu_read_unlock();
2218 }
2219
2220 static void sock_def_error_report(struct sock *sk)
2221 {
2222 struct socket_wq *wq;
2223
2224 rcu_read_lock();
2225 wq = rcu_dereference(sk->sk_wq);
2226 if (wq_has_sleeper(wq))
2227 wake_up_interruptible_poll(&wq->wait, POLLERR);
2228 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2229 rcu_read_unlock();
2230 }
2231
2232 static void sock_def_readable(struct sock *sk)
2233 {
2234 struct socket_wq *wq;
2235
2236 rcu_read_lock();
2237 wq = rcu_dereference(sk->sk_wq);
2238 if (wq_has_sleeper(wq))
2239 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2240 POLLRDNORM | POLLRDBAND);
2241 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2242 rcu_read_unlock();
2243 }
2244
2245 static void sock_def_write_space(struct sock *sk)
2246 {
2247 struct socket_wq *wq;
2248
2249 rcu_read_lock();
2250
2251 /* Do not wake up a writer until he can make "significant"
2252 * progress. --DaveM
2253 */
2254 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2255 wq = rcu_dereference(sk->sk_wq);
2256 if (wq_has_sleeper(wq))
2257 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2258 POLLWRNORM | POLLWRBAND);
2259
2260 /* Should agree with poll, otherwise some programs break */
2261 if (sock_writeable(sk))
2262 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2263 }
2264
2265 rcu_read_unlock();
2266 }
2267
2268 static void sock_def_destruct(struct sock *sk)
2269 {
2270 kfree(sk->sk_protinfo);
2271 }
2272
2273 void sk_send_sigurg(struct sock *sk)
2274 {
2275 if (sk->sk_socket && sk->sk_socket->file)
2276 if (send_sigurg(&sk->sk_socket->file->f_owner))
2277 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2278 }
2279 EXPORT_SYMBOL(sk_send_sigurg);
2280
2281 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2282 unsigned long expires)
2283 {
2284 if (!mod_timer(timer, expires))
2285 sock_hold(sk);
2286 }
2287 EXPORT_SYMBOL(sk_reset_timer);
2288
2289 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2290 {
2291 if (del_timer(timer))
2292 __sock_put(sk);
2293 }
2294 EXPORT_SYMBOL(sk_stop_timer);
2295
2296 void sock_init_data(struct socket *sock, struct sock *sk)
2297 {
2298 skb_queue_head_init(&sk->sk_receive_queue);
2299 skb_queue_head_init(&sk->sk_write_queue);
2300 skb_queue_head_init(&sk->sk_error_queue);
2301
2302 sk->sk_send_head = NULL;
2303
2304 init_timer(&sk->sk_timer);
2305
2306 sk->sk_allocation = GFP_KERNEL;
2307 sk->sk_rcvbuf = sysctl_rmem_default;
2308 sk->sk_sndbuf = sysctl_wmem_default;
2309 sk->sk_state = TCP_CLOSE;
2310 sk_set_socket(sk, sock);
2311
2312 sock_set_flag(sk, SOCK_ZAPPED);
2313
2314 if (sock) {
2315 sk->sk_type = sock->type;
2316 sk->sk_wq = sock->wq;
2317 sock->sk = sk;
2318 } else
2319 sk->sk_wq = NULL;
2320
2321 spin_lock_init(&sk->sk_dst_lock);
2322 rwlock_init(&sk->sk_callback_lock);
2323 lockdep_set_class_and_name(&sk->sk_callback_lock,
2324 af_callback_keys + sk->sk_family,
2325 af_family_clock_key_strings[sk->sk_family]);
2326
2327 sk->sk_state_change = sock_def_wakeup;
2328 sk->sk_data_ready = sock_def_readable;
2329 sk->sk_write_space = sock_def_write_space;
2330 sk->sk_error_report = sock_def_error_report;
2331 sk->sk_destruct = sock_def_destruct;
2332
2333 sk->sk_frag.page = NULL;
2334 sk->sk_frag.offset = 0;
2335 sk->sk_peek_off = -1;
2336
2337 sk->sk_peer_pid = NULL;
2338 sk->sk_peer_cred = NULL;
2339 sk->sk_write_pending = 0;
2340 sk->sk_rcvlowat = 1;
2341 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2342 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2343
2344 sk->sk_stamp = ktime_set(-1L, 0);
2345
2346 #ifdef CONFIG_NET_RX_BUSY_POLL
2347 sk->sk_napi_id = 0;
2348 sk->sk_ll_usec = sysctl_net_busy_read;
2349 #endif
2350
2351 sk->sk_max_pacing_rate = ~0U;
2352 sk->sk_pacing_rate = ~0U;
2353 /*
2354 * Before updating sk_refcnt, we must commit prior changes to memory
2355 * (Documentation/RCU/rculist_nulls.txt for details)
2356 */
2357 smp_wmb();
2358 atomic_set(&sk->sk_refcnt, 1);
2359 atomic_set(&sk->sk_drops, 0);
2360 }
2361 EXPORT_SYMBOL(sock_init_data);
2362
2363 void lock_sock_nested(struct sock *sk, int subclass)
2364 {
2365 might_sleep();
2366 spin_lock_bh(&sk->sk_lock.slock);
2367 if (sk->sk_lock.owned)
2368 __lock_sock(sk);
2369 sk->sk_lock.owned = 1;
2370 spin_unlock(&sk->sk_lock.slock);
2371 /*
2372 * The sk_lock has mutex_lock() semantics here:
2373 */
2374 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2375 local_bh_enable();
2376 }
2377 EXPORT_SYMBOL(lock_sock_nested);
2378
2379 void release_sock(struct sock *sk)
2380 {
2381 /*
2382 * The sk_lock has mutex_unlock() semantics:
2383 */
2384 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2385
2386 spin_lock_bh(&sk->sk_lock.slock);
2387 if (sk->sk_backlog.tail)
2388 __release_sock(sk);
2389
2390 /* Warning : release_cb() might need to release sk ownership,
2391 * ie call sock_release_ownership(sk) before us.
2392 */
2393 if (sk->sk_prot->release_cb)
2394 sk->sk_prot->release_cb(sk);
2395
2396 sock_release_ownership(sk);
2397 if (waitqueue_active(&sk->sk_lock.wq))
2398 wake_up(&sk->sk_lock.wq);
2399 spin_unlock_bh(&sk->sk_lock.slock);
2400 }
2401 EXPORT_SYMBOL(release_sock);
2402
2403 /**
2404 * lock_sock_fast - fast version of lock_sock
2405 * @sk: socket
2406 *
2407 * This version should be used for very small section, where process wont block
2408 * return false if fast path is taken
2409 * sk_lock.slock locked, owned = 0, BH disabled
2410 * return true if slow path is taken
2411 * sk_lock.slock unlocked, owned = 1, BH enabled
2412 */
2413 bool lock_sock_fast(struct sock *sk)
2414 {
2415 might_sleep();
2416 spin_lock_bh(&sk->sk_lock.slock);
2417
2418 if (!sk->sk_lock.owned)
2419 /*
2420 * Note : We must disable BH
2421 */
2422 return false;
2423
2424 __lock_sock(sk);
2425 sk->sk_lock.owned = 1;
2426 spin_unlock(&sk->sk_lock.slock);
2427 /*
2428 * The sk_lock has mutex_lock() semantics here:
2429 */
2430 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2431 local_bh_enable();
2432 return true;
2433 }
2434 EXPORT_SYMBOL(lock_sock_fast);
2435
2436 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2437 {
2438 struct timeval tv;
2439 if (!sock_flag(sk, SOCK_TIMESTAMP))
2440 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2441 tv = ktime_to_timeval(sk->sk_stamp);
2442 if (tv.tv_sec == -1)
2443 return -ENOENT;
2444 if (tv.tv_sec == 0) {
2445 sk->sk_stamp = ktime_get_real();
2446 tv = ktime_to_timeval(sk->sk_stamp);
2447 }
2448 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2449 }
2450 EXPORT_SYMBOL(sock_get_timestamp);
2451
2452 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2453 {
2454 struct timespec ts;
2455 if (!sock_flag(sk, SOCK_TIMESTAMP))
2456 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2457 ts = ktime_to_timespec(sk->sk_stamp);
2458 if (ts.tv_sec == -1)
2459 return -ENOENT;
2460 if (ts.tv_sec == 0) {
2461 sk->sk_stamp = ktime_get_real();
2462 ts = ktime_to_timespec(sk->sk_stamp);
2463 }
2464 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2465 }
2466 EXPORT_SYMBOL(sock_get_timestampns);
2467
2468 void sock_enable_timestamp(struct sock *sk, int flag)
2469 {
2470 if (!sock_flag(sk, flag)) {
2471 unsigned long previous_flags = sk->sk_flags;
2472
2473 sock_set_flag(sk, flag);
2474 /*
2475 * we just set one of the two flags which require net
2476 * time stamping, but time stamping might have been on
2477 * already because of the other one
2478 */
2479 if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2480 net_enable_timestamp();
2481 }
2482 }
2483
2484 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2485 int level, int type)
2486 {
2487 struct sock_exterr_skb *serr;
2488 struct sk_buff *skb;
2489 int copied, err;
2490
2491 err = -EAGAIN;
2492 skb = sock_dequeue_err_skb(sk);
2493 if (skb == NULL)
2494 goto out;
2495
2496 copied = skb->len;
2497 if (copied > len) {
2498 msg->msg_flags |= MSG_TRUNC;
2499 copied = len;
2500 }
2501 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2502 if (err)
2503 goto out_free_skb;
2504
2505 sock_recv_timestamp(msg, sk, skb);
2506
2507 serr = SKB_EXT_ERR(skb);
2508 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2509
2510 msg->msg_flags |= MSG_ERRQUEUE;
2511 err = copied;
2512
2513 out_free_skb:
2514 kfree_skb(skb);
2515 out:
2516 return err;
2517 }
2518 EXPORT_SYMBOL(sock_recv_errqueue);
2519
2520 /*
2521 * Get a socket option on an socket.
2522 *
2523 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2524 * asynchronous errors should be reported by getsockopt. We assume
2525 * this means if you specify SO_ERROR (otherwise whats the point of it).
2526 */
2527 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2528 char __user *optval, int __user *optlen)
2529 {
2530 struct sock *sk = sock->sk;
2531
2532 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2533 }
2534 EXPORT_SYMBOL(sock_common_getsockopt);
2535
2536 #ifdef CONFIG_COMPAT
2537 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2538 char __user *optval, int __user *optlen)
2539 {
2540 struct sock *sk = sock->sk;
2541
2542 if (sk->sk_prot->compat_getsockopt != NULL)
2543 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2544 optval, optlen);
2545 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2546 }
2547 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2548 #endif
2549
2550 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2551 struct msghdr *msg, size_t size, int flags)
2552 {
2553 struct sock *sk = sock->sk;
2554 int addr_len = 0;
2555 int err;
2556
2557 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2558 flags & ~MSG_DONTWAIT, &addr_len);
2559 if (err >= 0)
2560 msg->msg_namelen = addr_len;
2561 return err;
2562 }
2563 EXPORT_SYMBOL(sock_common_recvmsg);
2564
2565 /*
2566 * Set socket options on an inet socket.
2567 */
2568 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2569 char __user *optval, unsigned int optlen)
2570 {
2571 struct sock *sk = sock->sk;
2572
2573 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2574 }
2575 EXPORT_SYMBOL(sock_common_setsockopt);
2576
2577 #ifdef CONFIG_COMPAT
2578 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2579 char __user *optval, unsigned int optlen)
2580 {
2581 struct sock *sk = sock->sk;
2582
2583 if (sk->sk_prot->compat_setsockopt != NULL)
2584 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2585 optval, optlen);
2586 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2587 }
2588 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2589 #endif
2590
2591 void sk_common_release(struct sock *sk)
2592 {
2593 if (sk->sk_prot->destroy)
2594 sk->sk_prot->destroy(sk);
2595
2596 /*
2597 * Observation: when sock_common_release is called, processes have
2598 * no access to socket. But net still has.
2599 * Step one, detach it from networking:
2600 *
2601 * A. Remove from hash tables.
2602 */
2603
2604 sk->sk_prot->unhash(sk);
2605
2606 /*
2607 * In this point socket cannot receive new packets, but it is possible
2608 * that some packets are in flight because some CPU runs receiver and
2609 * did hash table lookup before we unhashed socket. They will achieve
2610 * receive queue and will be purged by socket destructor.
2611 *
2612 * Also we still have packets pending on receive queue and probably,
2613 * our own packets waiting in device queues. sock_destroy will drain
2614 * receive queue, but transmitted packets will delay socket destruction
2615 * until the last reference will be released.
2616 */
2617
2618 sock_orphan(sk);
2619
2620 xfrm_sk_free_policy(sk);
2621
2622 sk_refcnt_debug_release(sk);
2623
2624 if (sk->sk_frag.page) {
2625 put_page(sk->sk_frag.page);
2626 sk->sk_frag.page = NULL;
2627 }
2628
2629 sock_put(sk);
2630 }
2631 EXPORT_SYMBOL(sk_common_release);
2632
2633 #ifdef CONFIG_PROC_FS
2634 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2635 struct prot_inuse {
2636 int val[PROTO_INUSE_NR];
2637 };
2638
2639 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2640
2641 #ifdef CONFIG_NET_NS
2642 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2643 {
2644 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2645 }
2646 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2647
2648 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2649 {
2650 int cpu, idx = prot->inuse_idx;
2651 int res = 0;
2652
2653 for_each_possible_cpu(cpu)
2654 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2655
2656 return res >= 0 ? res : 0;
2657 }
2658 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2659
2660 static int __net_init sock_inuse_init_net(struct net *net)
2661 {
2662 net->core.inuse = alloc_percpu(struct prot_inuse);
2663 return net->core.inuse ? 0 : -ENOMEM;
2664 }
2665
2666 static void __net_exit sock_inuse_exit_net(struct net *net)
2667 {
2668 free_percpu(net->core.inuse);
2669 }
2670
2671 static struct pernet_operations net_inuse_ops = {
2672 .init = sock_inuse_init_net,
2673 .exit = sock_inuse_exit_net,
2674 };
2675
2676 static __init int net_inuse_init(void)
2677 {
2678 if (register_pernet_subsys(&net_inuse_ops))
2679 panic("Cannot initialize net inuse counters");
2680
2681 return 0;
2682 }
2683
2684 core_initcall(net_inuse_init);
2685 #else
2686 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2687
2688 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2689 {
2690 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2691 }
2692 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2693
2694 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2695 {
2696 int cpu, idx = prot->inuse_idx;
2697 int res = 0;
2698
2699 for_each_possible_cpu(cpu)
2700 res += per_cpu(prot_inuse, cpu).val[idx];
2701
2702 return res >= 0 ? res : 0;
2703 }
2704 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2705 #endif
2706
2707 static void assign_proto_idx(struct proto *prot)
2708 {
2709 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2710
2711 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2712 pr_err("PROTO_INUSE_NR exhausted\n");
2713 return;
2714 }
2715
2716 set_bit(prot->inuse_idx, proto_inuse_idx);
2717 }
2718
2719 static void release_proto_idx(struct proto *prot)
2720 {
2721 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2722 clear_bit(prot->inuse_idx, proto_inuse_idx);
2723 }
2724 #else
2725 static inline void assign_proto_idx(struct proto *prot)
2726 {
2727 }
2728
2729 static inline void release_proto_idx(struct proto *prot)
2730 {
2731 }
2732 #endif
2733
2734 int proto_register(struct proto *prot, int alloc_slab)
2735 {
2736 if (alloc_slab) {
2737 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2738 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2739 NULL);
2740
2741 if (prot->slab == NULL) {
2742 pr_crit("%s: Can't create sock SLAB cache!\n",
2743 prot->name);
2744 goto out;
2745 }
2746
2747 if (prot->rsk_prot != NULL) {
2748 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2749 if (prot->rsk_prot->slab_name == NULL)
2750 goto out_free_sock_slab;
2751
2752 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2753 prot->rsk_prot->obj_size, 0,
2754 SLAB_HWCACHE_ALIGN, NULL);
2755
2756 if (prot->rsk_prot->slab == NULL) {
2757 pr_crit("%s: Can't create request sock SLAB cache!\n",
2758 prot->name);
2759 goto out_free_request_sock_slab_name;
2760 }
2761 }
2762
2763 if (prot->twsk_prot != NULL) {
2764 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2765
2766 if (prot->twsk_prot->twsk_slab_name == NULL)
2767 goto out_free_request_sock_slab;
2768
2769 prot->twsk_prot->twsk_slab =
2770 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2771 prot->twsk_prot->twsk_obj_size,
2772 0,
2773 SLAB_HWCACHE_ALIGN |
2774 prot->slab_flags,
2775 NULL);
2776 if (prot->twsk_prot->twsk_slab == NULL)
2777 goto out_free_timewait_sock_slab_name;
2778 }
2779 }
2780
2781 mutex_lock(&proto_list_mutex);
2782 list_add(&prot->node, &proto_list);
2783 assign_proto_idx(prot);
2784 mutex_unlock(&proto_list_mutex);
2785 return 0;
2786
2787 out_free_timewait_sock_slab_name:
2788 kfree(prot->twsk_prot->twsk_slab_name);
2789 out_free_request_sock_slab:
2790 if (prot->rsk_prot && prot->rsk_prot->slab) {
2791 kmem_cache_destroy(prot->rsk_prot->slab);
2792 prot->rsk_prot->slab = NULL;
2793 }
2794 out_free_request_sock_slab_name:
2795 if (prot->rsk_prot)
2796 kfree(prot->rsk_prot->slab_name);
2797 out_free_sock_slab:
2798 kmem_cache_destroy(prot->slab);
2799 prot->slab = NULL;
2800 out:
2801 return -ENOBUFS;
2802 }
2803 EXPORT_SYMBOL(proto_register);
2804
2805 void proto_unregister(struct proto *prot)
2806 {
2807 mutex_lock(&proto_list_mutex);
2808 release_proto_idx(prot);
2809 list_del(&prot->node);
2810 mutex_unlock(&proto_list_mutex);
2811
2812 if (prot->slab != NULL) {
2813 kmem_cache_destroy(prot->slab);
2814 prot->slab = NULL;
2815 }
2816
2817 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2818 kmem_cache_destroy(prot->rsk_prot->slab);
2819 kfree(prot->rsk_prot->slab_name);
2820 prot->rsk_prot->slab = NULL;
2821 }
2822
2823 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2824 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2825 kfree(prot->twsk_prot->twsk_slab_name);
2826 prot->twsk_prot->twsk_slab = NULL;
2827 }
2828 }
2829 EXPORT_SYMBOL(proto_unregister);
2830
2831 #ifdef CONFIG_PROC_FS
2832 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2833 __acquires(proto_list_mutex)
2834 {
2835 mutex_lock(&proto_list_mutex);
2836 return seq_list_start_head(&proto_list, *pos);
2837 }
2838
2839 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2840 {
2841 return seq_list_next(v, &proto_list, pos);
2842 }
2843
2844 static void proto_seq_stop(struct seq_file *seq, void *v)
2845 __releases(proto_list_mutex)
2846 {
2847 mutex_unlock(&proto_list_mutex);
2848 }
2849
2850 static char proto_method_implemented(const void *method)
2851 {
2852 return method == NULL ? 'n' : 'y';
2853 }
2854 static long sock_prot_memory_allocated(struct proto *proto)
2855 {
2856 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2857 }
2858
2859 static char *sock_prot_memory_pressure(struct proto *proto)
2860 {
2861 return proto->memory_pressure != NULL ?
2862 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2863 }
2864
2865 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2866 {
2867
2868 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2869 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2870 proto->name,
2871 proto->obj_size,
2872 sock_prot_inuse_get(seq_file_net(seq), proto),
2873 sock_prot_memory_allocated(proto),
2874 sock_prot_memory_pressure(proto),
2875 proto->max_header,
2876 proto->slab == NULL ? "no" : "yes",
2877 module_name(proto->owner),
2878 proto_method_implemented(proto->close),
2879 proto_method_implemented(proto->connect),
2880 proto_method_implemented(proto->disconnect),
2881 proto_method_implemented(proto->accept),
2882 proto_method_implemented(proto->ioctl),
2883 proto_method_implemented(proto->init),
2884 proto_method_implemented(proto->destroy),
2885 proto_method_implemented(proto->shutdown),
2886 proto_method_implemented(proto->setsockopt),
2887 proto_method_implemented(proto->getsockopt),
2888 proto_method_implemented(proto->sendmsg),
2889 proto_method_implemented(proto->recvmsg),
2890 proto_method_implemented(proto->sendpage),
2891 proto_method_implemented(proto->bind),
2892 proto_method_implemented(proto->backlog_rcv),
2893 proto_method_implemented(proto->hash),
2894 proto_method_implemented(proto->unhash),
2895 proto_method_implemented(proto->get_port),
2896 proto_method_implemented(proto->enter_memory_pressure));
2897 }
2898
2899 static int proto_seq_show(struct seq_file *seq, void *v)
2900 {
2901 if (v == &proto_list)
2902 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2903 "protocol",
2904 "size",
2905 "sockets",
2906 "memory",
2907 "press",
2908 "maxhdr",
2909 "slab",
2910 "module",
2911 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2912 else
2913 proto_seq_printf(seq, list_entry(v, struct proto, node));
2914 return 0;
2915 }
2916
2917 static const struct seq_operations proto_seq_ops = {
2918 .start = proto_seq_start,
2919 .next = proto_seq_next,
2920 .stop = proto_seq_stop,
2921 .show = proto_seq_show,
2922 };
2923
2924 static int proto_seq_open(struct inode *inode, struct file *file)
2925 {
2926 return seq_open_net(inode, file, &proto_seq_ops,
2927 sizeof(struct seq_net_private));
2928 }
2929
2930 static const struct file_operations proto_seq_fops = {
2931 .owner = THIS_MODULE,
2932 .open = proto_seq_open,
2933 .read = seq_read,
2934 .llseek = seq_lseek,
2935 .release = seq_release_net,
2936 };
2937
2938 static __net_init int proto_init_net(struct net *net)
2939 {
2940 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
2941 return -ENOMEM;
2942
2943 return 0;
2944 }
2945
2946 static __net_exit void proto_exit_net(struct net *net)
2947 {
2948 remove_proc_entry("protocols", net->proc_net);
2949 }
2950
2951
2952 static __net_initdata struct pernet_operations proto_net_ops = {
2953 .init = proto_init_net,
2954 .exit = proto_exit_net,
2955 };
2956
2957 static int __init proto_init(void)
2958 {
2959 return register_pernet_subsys(&proto_net_ops);
2960 }
2961
2962 subsys_initcall(proto_init);
2963
2964 #endif /* PROC_FS */
(deprecated) Btrfs devel tree