projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net...
[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
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 #ifdef CONFIG_MEMCG_KMEM
149 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
150 {
151 struct proto *proto;
152 int ret = 0;
153
154 mutex_lock(&proto_list_mutex);
155 list_for_each_entry(proto, &proto_list, node) {
156 if (proto->init_cgroup) {
157 ret = proto->init_cgroup(memcg, ss);
158 if (ret)
159 goto out;
160 }
161 }
162
163 mutex_unlock(&proto_list_mutex);
164 return ret;
165 out:
166 list_for_each_entry_continue_reverse(proto, &proto_list, node)
167 if (proto->destroy_cgroup)
168 proto->destroy_cgroup(memcg);
169 mutex_unlock(&proto_list_mutex);
170 return ret;
171 }
172
173 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
174 {
175 struct proto *proto;
176
177 mutex_lock(&proto_list_mutex);
178 list_for_each_entry_reverse(proto, &proto_list, node)
179 if (proto->destroy_cgroup)
180 proto->destroy_cgroup(memcg);
181 mutex_unlock(&proto_list_mutex);
182 }
183 #endif
184
185 /*
186 * Each address family might have different locking rules, so we have
187 * one slock key per address family:
188 */
189 static struct lock_class_key af_family_keys[AF_MAX];
190 static struct lock_class_key af_family_slock_keys[AF_MAX];
191
192 #if defined(CONFIG_MEMCG_KMEM)
193 struct static_key memcg_socket_limit_enabled;
194 EXPORT_SYMBOL(memcg_socket_limit_enabled);
195 #endif
196
197 /*
198 * Make lock validator output more readable. (we pre-construct these
199 * strings build-time, so that runtime initialization of socket
200 * locks is fast):
201 */
202 static const char *const af_family_key_strings[AF_MAX+1] = {
203 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
204 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
205 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
206 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
207 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
208 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
209 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
210 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
211 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
212 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
213 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
214 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
215 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
216 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
217 };
218 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
219 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
220 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
221 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
222 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
223 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
224 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
225 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
226 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
227 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
228 "slock-27" , "slock-28" , "slock-AF_CAN" ,
229 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
230 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
231 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
232 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
233 };
234 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
235 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
236 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
237 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
238 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
239 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
240 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
241 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
242 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
243 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
244 "clock-27" , "clock-28" , "clock-AF_CAN" ,
245 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
246 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
247 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
248 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
249 };
250
251 /*
252 * sk_callback_lock locking rules are per-address-family,
253 * so split the lock classes by using a per-AF key:
254 */
255 static struct lock_class_key af_callback_keys[AF_MAX];
256
257 /* Take into consideration the size of the struct sk_buff overhead in the
258 * determination of these values, since that is non-constant across
259 * platforms. This makes socket queueing behavior and performance
260 * not depend upon such differences.
261 */
262 #define _SK_MEM_PACKETS 256
263 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
264 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
265 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
266
267 /* Run time adjustable parameters. */
268 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
269 EXPORT_SYMBOL(sysctl_wmem_max);
270 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
271 EXPORT_SYMBOL(sysctl_rmem_max);
272 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
273 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
274
275 /* Maximal space eaten by iovec or ancillary data plus some space */
276 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
277 EXPORT_SYMBOL(sysctl_optmem_max);
278
279 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
280 EXPORT_SYMBOL_GPL(memalloc_socks);
281
282 /**
283 * sk_set_memalloc - sets %SOCK_MEMALLOC
284 * @sk: socket to set it on
285 *
286 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
287 * It's the responsibility of the admin to adjust min_free_kbytes
288 * to meet the requirements
289 */
290 void sk_set_memalloc(struct sock *sk)
291 {
292 sock_set_flag(sk, SOCK_MEMALLOC);
293 sk->sk_allocation |= __GFP_MEMALLOC;
294 static_key_slow_inc(&memalloc_socks);
295 }
296 EXPORT_SYMBOL_GPL(sk_set_memalloc);
297
298 void sk_clear_memalloc(struct sock *sk)
299 {
300 sock_reset_flag(sk, SOCK_MEMALLOC);
301 sk->sk_allocation &= ~__GFP_MEMALLOC;
302 static_key_slow_dec(&memalloc_socks);
303
304 /*
305 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
306 * progress of swapping. However, if SOCK_MEMALLOC is cleared while
307 * it has rmem allocations there is a risk that the user of the
308 * socket cannot make forward progress due to exceeding the rmem
309 * limits. By rights, sk_clear_memalloc() should only be called
310 * on sockets being torn down but warn and reset the accounting if
311 * that assumption breaks.
312 */
313 if (WARN_ON(sk->sk_forward_alloc))
314 sk_mem_reclaim(sk);
315 }
316 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
317
318 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
319 {
320 int ret;
321 unsigned long pflags = current->flags;
322
323 /* these should have been dropped before queueing */
324 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
325
326 current->flags |= PF_MEMALLOC;
327 ret = sk->sk_backlog_rcv(sk, skb);
328 tsk_restore_flags(current, pflags, PF_MEMALLOC);
329
330 return ret;
331 }
332 EXPORT_SYMBOL(__sk_backlog_rcv);
333
334 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
335 {
336 struct timeval tv;
337
338 if (optlen < sizeof(tv))
339 return -EINVAL;
340 if (copy_from_user(&tv, optval, sizeof(tv)))
341 return -EFAULT;
342 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
343 return -EDOM;
344
345 if (tv.tv_sec < 0) {
346 static int warned __read_mostly;
347
348 *timeo_p = 0;
349 if (warned < 10 && net_ratelimit()) {
350 warned++;
351 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
352 __func__, current->comm, task_pid_nr(current));
353 }
354 return 0;
355 }
356 *timeo_p = MAX_SCHEDULE_TIMEOUT;
357 if (tv.tv_sec == 0 && tv.tv_usec == 0)
358 return 0;
359 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
360 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
361 return 0;
362 }
363
364 static void sock_warn_obsolete_bsdism(const char *name)
365 {
366 static int warned;
367 static char warncomm[TASK_COMM_LEN];
368 if (strcmp(warncomm, current->comm) && warned < 5) {
369 strcpy(warncomm, current->comm);
370 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
371 warncomm, name);
372 warned++;
373 }
374 }
375
376 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
377
378 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
379 {
380 if (sk->sk_flags & flags) {
381 sk->sk_flags &= ~flags;
382 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
383 net_disable_timestamp();
384 }
385 }
386
387
388 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
389 {
390 int err;
391 int skb_len;
392 unsigned long flags;
393 struct sk_buff_head *list = &sk->sk_receive_queue;
394
395 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
396 atomic_inc(&sk->sk_drops);
397 trace_sock_rcvqueue_full(sk, skb);
398 return -ENOMEM;
399 }
400
401 err = sk_filter(sk, skb);
402 if (err)
403 return err;
404
405 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
406 atomic_inc(&sk->sk_drops);
407 return -ENOBUFS;
408 }
409
410 skb->dev = NULL;
411 skb_set_owner_r(skb, sk);
412
413 /* Cache the SKB length before we tack it onto the receive
414 * queue. Once it is added it no longer belongs to us and
415 * may be freed by other threads of control pulling packets
416 * from the queue.
417 */
418 skb_len = skb->len;
419
420 /* we escape from rcu protected region, make sure we dont leak
421 * a norefcounted dst
422 */
423 skb_dst_force(skb);
424
425 spin_lock_irqsave(&list->lock, flags);
426 skb->dropcount = atomic_read(&sk->sk_drops);
427 __skb_queue_tail(list, skb);
428 spin_unlock_irqrestore(&list->lock, flags);
429
430 if (!sock_flag(sk, SOCK_DEAD))
431 sk->sk_data_ready(sk, skb_len);
432 return 0;
433 }
434 EXPORT_SYMBOL(sock_queue_rcv_skb);
435
436 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
437 {
438 int rc = NET_RX_SUCCESS;
439
440 if (sk_filter(sk, skb))
441 goto discard_and_relse;
442
443 skb->dev = NULL;
444
445 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
446 atomic_inc(&sk->sk_drops);
447 goto discard_and_relse;
448 }
449 if (nested)
450 bh_lock_sock_nested(sk);
451 else
452 bh_lock_sock(sk);
453 if (!sock_owned_by_user(sk)) {
454 /*
455 * trylock + unlock semantics:
456 */
457 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
458
459 rc = sk_backlog_rcv(sk, skb);
460
461 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
462 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
463 bh_unlock_sock(sk);
464 atomic_inc(&sk->sk_drops);
465 goto discard_and_relse;
466 }
467
468 bh_unlock_sock(sk);
469 out:
470 sock_put(sk);
471 return rc;
472 discard_and_relse:
473 kfree_skb(skb);
474 goto out;
475 }
476 EXPORT_SYMBOL(sk_receive_skb);
477
478 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
479 {
480 struct dst_entry *dst = __sk_dst_get(sk);
481
482 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
483 sk_tx_queue_clear(sk);
484 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
485 dst_release(dst);
486 return NULL;
487 }
488
489 return dst;
490 }
491 EXPORT_SYMBOL(__sk_dst_check);
492
493 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
494 {
495 struct dst_entry *dst = sk_dst_get(sk);
496
497 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
498 sk_dst_reset(sk);
499 dst_release(dst);
500 return NULL;
501 }
502
503 return dst;
504 }
505 EXPORT_SYMBOL(sk_dst_check);
506
507 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
508 int optlen)
509 {
510 int ret = -ENOPROTOOPT;
511 #ifdef CONFIG_NETDEVICES
512 struct net *net = sock_net(sk);
513 char devname[IFNAMSIZ];
514 int index;
515
516 /* Sorry... */
517 ret = -EPERM;
518 if (!ns_capable(net->user_ns, CAP_NET_RAW))
519 goto out;
520
521 ret = -EINVAL;
522 if (optlen < 0)
523 goto out;
524
525 /* Bind this socket to a particular device like "eth0",
526 * as specified in the passed interface name. If the
527 * name is "" or the option length is zero the socket
528 * is not bound.
529 */
530 if (optlen > IFNAMSIZ - 1)
531 optlen = IFNAMSIZ - 1;
532 memset(devname, 0, sizeof(devname));
533
534 ret = -EFAULT;
535 if (copy_from_user(devname, optval, optlen))
536 goto out;
537
538 index = 0;
539 if (devname[0] != '\0') {
540 struct net_device *dev;
541
542 rcu_read_lock();
543 dev = dev_get_by_name_rcu(net, devname);
544 if (dev)
545 index = dev->ifindex;
546 rcu_read_unlock();
547 ret = -ENODEV;
548 if (!dev)
549 goto out;
550 }
551
552 lock_sock(sk);
553 sk->sk_bound_dev_if = index;
554 sk_dst_reset(sk);
555 release_sock(sk);
556
557 ret = 0;
558
559 out:
560 #endif
561
562 return ret;
563 }
564
565 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
566 int __user *optlen, int len)
567 {
568 int ret = -ENOPROTOOPT;
569 #ifdef CONFIG_NETDEVICES
570 struct net *net = sock_net(sk);
571 char devname[IFNAMSIZ];
572
573 if (sk->sk_bound_dev_if == 0) {
574 len = 0;
575 goto zero;
576 }
577
578 ret = -EINVAL;
579 if (len < IFNAMSIZ)
580 goto out;
581
582 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
583 if (ret)
584 goto out;
585
586 len = strlen(devname) + 1;
587
588 ret = -EFAULT;
589 if (copy_to_user(optval, devname, len))
590 goto out;
591
592 zero:
593 ret = -EFAULT;
594 if (put_user(len, optlen))
595 goto out;
596
597 ret = 0;
598
599 out:
600 #endif
601
602 return ret;
603 }
604
605 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
606 {
607 if (valbool)
608 sock_set_flag(sk, bit);
609 else
610 sock_reset_flag(sk, bit);
611 }
612
613 /*
614 * This is meant for all protocols to use and covers goings on
615 * at the socket level. Everything here is generic.
616 */
617
618 int sock_setsockopt(struct socket *sock, int level, int optname,
619 char __user *optval, unsigned int optlen)
620 {
621 struct sock *sk = sock->sk;
622 int val;
623 int valbool;
624 struct linger ling;
625 int ret = 0;
626
627 /*
628 * Options without arguments
629 */
630
631 if (optname == SO_BINDTODEVICE)
632 return sock_setbindtodevice(sk, optval, optlen);
633
634 if (optlen < sizeof(int))
635 return -EINVAL;
636
637 if (get_user(val, (int __user *)optval))
638 return -EFAULT;
639
640 valbool = val ? 1 : 0;
641
642 lock_sock(sk);
643
644 switch (optname) {
645 case SO_DEBUG:
646 if (val && !capable(CAP_NET_ADMIN))
647 ret = -EACCES;
648 else
649 sock_valbool_flag(sk, SOCK_DBG, valbool);
650 break;
651 case SO_REUSEADDR:
652 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
653 break;
654 case SO_REUSEPORT:
655 sk->sk_reuseport = valbool;
656 break;
657 case SO_TYPE:
658 case SO_PROTOCOL:
659 case SO_DOMAIN:
660 case SO_ERROR:
661 ret = -ENOPROTOOPT;
662 break;
663 case SO_DONTROUTE:
664 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
665 break;
666 case SO_BROADCAST:
667 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
668 break;
669 case SO_SNDBUF:
670 /* Don't error on this BSD doesn't and if you think
671 * about it this is right. Otherwise apps have to
672 * play 'guess the biggest size' games. RCVBUF/SNDBUF
673 * are treated in BSD as hints
674 */
675 val = min_t(u32, val, sysctl_wmem_max);
676 set_sndbuf:
677 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
678 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
679 /* Wake up sending tasks if we upped the value. */
680 sk->sk_write_space(sk);
681 break;
682
683 case SO_SNDBUFFORCE:
684 if (!capable(CAP_NET_ADMIN)) {
685 ret = -EPERM;
686 break;
687 }
688 goto set_sndbuf;
689
690 case SO_RCVBUF:
691 /* Don't error on this BSD doesn't and if you think
692 * about it this is right. Otherwise apps have to
693 * play 'guess the biggest size' games. RCVBUF/SNDBUF
694 * are treated in BSD as hints
695 */
696 val = min_t(u32, val, sysctl_rmem_max);
697 set_rcvbuf:
698 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
699 /*
700 * We double it on the way in to account for
701 * "struct sk_buff" etc. overhead. Applications
702 * assume that the SO_RCVBUF setting they make will
703 * allow that much actual data to be received on that
704 * socket.
705 *
706 * Applications are unaware that "struct sk_buff" and
707 * other overheads allocate from the receive buffer
708 * during socket buffer allocation.
709 *
710 * And after considering the possible alternatives,
711 * returning the value we actually used in getsockopt
712 * is the most desirable behavior.
713 */
714 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
715 break;
716
717 case SO_RCVBUFFORCE:
718 if (!capable(CAP_NET_ADMIN)) {
719 ret = -EPERM;
720 break;
721 }
722 goto set_rcvbuf;
723
724 case SO_KEEPALIVE:
725 #ifdef CONFIG_INET
726 if (sk->sk_protocol == IPPROTO_TCP &&
727 sk->sk_type == SOCK_STREAM)
728 tcp_set_keepalive(sk, valbool);
729 #endif
730 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
731 break;
732
733 case SO_OOBINLINE:
734 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
735 break;
736
737 case SO_NO_CHECK:
738 sk->sk_no_check = valbool;
739 break;
740
741 case SO_PRIORITY:
742 if ((val >= 0 && val <= 6) ||
743 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
744 sk->sk_priority = val;
745 else
746 ret = -EPERM;
747 break;
748
749 case SO_LINGER:
750 if (optlen < sizeof(ling)) {
751 ret = -EINVAL; /* 1003.1g */
752 break;
753 }
754 if (copy_from_user(&ling, optval, sizeof(ling))) {
755 ret = -EFAULT;
756 break;
757 }
758 if (!ling.l_onoff)
759 sock_reset_flag(sk, SOCK_LINGER);
760 else {
761 #if (BITS_PER_LONG == 32)
762 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
763 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
764 else
765 #endif
766 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
767 sock_set_flag(sk, SOCK_LINGER);
768 }
769 break;
770
771 case SO_BSDCOMPAT:
772 sock_warn_obsolete_bsdism("setsockopt");
773 break;
774
775 case SO_PASSCRED:
776 if (valbool)
777 set_bit(SOCK_PASSCRED, &sock->flags);
778 else
779 clear_bit(SOCK_PASSCRED, &sock->flags);
780 break;
781
782 case SO_TIMESTAMP:
783 case SO_TIMESTAMPNS:
784 if (valbool) {
785 if (optname == SO_TIMESTAMP)
786 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
787 else
788 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
789 sock_set_flag(sk, SOCK_RCVTSTAMP);
790 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
791 } else {
792 sock_reset_flag(sk, SOCK_RCVTSTAMP);
793 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
794 }
795 break;
796
797 case SO_TIMESTAMPING:
798 if (val & ~SOF_TIMESTAMPING_MASK) {
799 ret = -EINVAL;
800 break;
801 }
802 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
803 val & SOF_TIMESTAMPING_TX_HARDWARE);
804 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
805 val & SOF_TIMESTAMPING_TX_SOFTWARE);
806 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
807 val & SOF_TIMESTAMPING_RX_HARDWARE);
808 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
809 sock_enable_timestamp(sk,
810 SOCK_TIMESTAMPING_RX_SOFTWARE);
811 else
812 sock_disable_timestamp(sk,
813 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
814 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
815 val & SOF_TIMESTAMPING_SOFTWARE);
816 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
817 val & SOF_TIMESTAMPING_SYS_HARDWARE);
818 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
819 val & SOF_TIMESTAMPING_RAW_HARDWARE);
820 break;
821
822 case SO_RCVLOWAT:
823 if (val < 0)
824 val = INT_MAX;
825 sk->sk_rcvlowat = val ? : 1;
826 break;
827
828 case SO_RCVTIMEO:
829 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
830 break;
831
832 case SO_SNDTIMEO:
833 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
834 break;
835
836 case SO_ATTACH_FILTER:
837 ret = -EINVAL;
838 if (optlen == sizeof(struct sock_fprog)) {
839 struct sock_fprog fprog;
840
841 ret = -EFAULT;
842 if (copy_from_user(&fprog, optval, sizeof(fprog)))
843 break;
844
845 ret = sk_attach_filter(&fprog, sk);
846 }
847 break;
848
849 case SO_DETACH_FILTER:
850 ret = sk_detach_filter(sk);
851 break;
852
853 case SO_LOCK_FILTER:
854 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
855 ret = -EPERM;
856 else
857 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
858 break;
859
860 case SO_PASSSEC:
861 if (valbool)
862 set_bit(SOCK_PASSSEC, &sock->flags);
863 else
864 clear_bit(SOCK_PASSSEC, &sock->flags);
865 break;
866 case SO_MARK:
867 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
868 ret = -EPERM;
869 else
870 sk->sk_mark = val;
871 break;
872
873 /* We implement the SO_SNDLOWAT etc to
874 not be settable (1003.1g 5.3) */
875 case SO_RXQ_OVFL:
876 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
877 break;
878
879 case SO_WIFI_STATUS:
880 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
881 break;
882
883 case SO_PEEK_OFF:
884 if (sock->ops->set_peek_off)
885 ret = sock->ops->set_peek_off(sk, val);
886 else
887 ret = -EOPNOTSUPP;
888 break;
889
890 case SO_NOFCS:
891 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
892 break;
893
894 case SO_SELECT_ERR_QUEUE:
895 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
896 break;
897
898 #ifdef CONFIG_NET_RX_BUSY_POLL
899 case SO_BUSY_POLL:
900 /* allow unprivileged users to decrease the value */
901 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
902 ret = -EPERM;
903 else {
904 if (val < 0)
905 ret = -EINVAL;
906 else
907 sk->sk_ll_usec = val;
908 }
909 break;
910 #endif
911
912 case SO_MAX_PACING_RATE:
913 sk->sk_max_pacing_rate = val;
914 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
915 sk->sk_max_pacing_rate);
916 break;
917
918 default:
919 ret = -ENOPROTOOPT;
920 break;
921 }
922 release_sock(sk);
923 return ret;
924 }
925 EXPORT_SYMBOL(sock_setsockopt);
926
927
928 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
929 struct ucred *ucred)
930 {
931 ucred->pid = pid_vnr(pid);
932 ucred->uid = ucred->gid = -1;
933 if (cred) {
934 struct user_namespace *current_ns = current_user_ns();
935
936 ucred->uid = from_kuid_munged(current_ns, cred->euid);
937 ucred->gid = from_kgid_munged(current_ns, cred->egid);
938 }
939 }
940
941 int sock_getsockopt(struct socket *sock, int level, int optname,
942 char __user *optval, int __user *optlen)
943 {
944 struct sock *sk = sock->sk;
945
946 union {
947 int val;
948 struct linger ling;
949 struct timeval tm;
950 } v;
951
952 int lv = sizeof(int);
953 int len;
954
955 if (get_user(len, optlen))
956 return -EFAULT;
957 if (len < 0)
958 return -EINVAL;
959
960 memset(&v, 0, sizeof(v));
961
962 switch (optname) {
963 case SO_DEBUG:
964 v.val = sock_flag(sk, SOCK_DBG);
965 break;
966
967 case SO_DONTROUTE:
968 v.val = sock_flag(sk, SOCK_LOCALROUTE);
969 break;
970
971 case SO_BROADCAST:
972 v.val = sock_flag(sk, SOCK_BROADCAST);
973 break;
974
975 case SO_SNDBUF:
976 v.val = sk->sk_sndbuf;
977 break;
978
979 case SO_RCVBUF:
980 v.val = sk->sk_rcvbuf;
981 break;
982
983 case SO_REUSEADDR:
984 v.val = sk->sk_reuse;
985 break;
986
987 case SO_REUSEPORT:
988 v.val = sk->sk_reuseport;
989 break;
990
991 case SO_KEEPALIVE:
992 v.val = sock_flag(sk, SOCK_KEEPOPEN);
993 break;
994
995 case SO_TYPE:
996 v.val = sk->sk_type;
997 break;
998
999 case SO_PROTOCOL:
1000 v.val = sk->sk_protocol;
1001 break;
1002
1003 case SO_DOMAIN:
1004 v.val = sk->sk_family;
1005 break;
1006
1007 case SO_ERROR:
1008 v.val = -sock_error(sk);
1009 if (v.val == 0)
1010 v.val = xchg(&sk->sk_err_soft, 0);
1011 break;
1012
1013 case SO_OOBINLINE:
1014 v.val = sock_flag(sk, SOCK_URGINLINE);
1015 break;
1016
1017 case SO_NO_CHECK:
1018 v.val = sk->sk_no_check;
1019 break;
1020
1021 case SO_PRIORITY:
1022 v.val = sk->sk_priority;
1023 break;
1024
1025 case SO_LINGER:
1026 lv = sizeof(v.ling);
1027 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1028 v.ling.l_linger = sk->sk_lingertime / HZ;
1029 break;
1030
1031 case SO_BSDCOMPAT:
1032 sock_warn_obsolete_bsdism("getsockopt");
1033 break;
1034
1035 case SO_TIMESTAMP:
1036 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1037 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1038 break;
1039
1040 case SO_TIMESTAMPNS:
1041 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1042 break;
1043
1044 case SO_TIMESTAMPING:
1045 v.val = 0;
1046 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
1047 v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
1048 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
1049 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
1050 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
1051 v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
1052 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1053 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
1054 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
1055 v.val |= SOF_TIMESTAMPING_SOFTWARE;
1056 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
1057 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
1058 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
1059 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
1060 break;
1061
1062 case SO_RCVTIMEO:
1063 lv = sizeof(struct timeval);
1064 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1065 v.tm.tv_sec = 0;
1066 v.tm.tv_usec = 0;
1067 } else {
1068 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1069 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1070 }
1071 break;
1072
1073 case SO_SNDTIMEO:
1074 lv = sizeof(struct timeval);
1075 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1076 v.tm.tv_sec = 0;
1077 v.tm.tv_usec = 0;
1078 } else {
1079 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1080 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1081 }
1082 break;
1083
1084 case SO_RCVLOWAT:
1085 v.val = sk->sk_rcvlowat;
1086 break;
1087
1088 case SO_SNDLOWAT:
1089 v.val = 1;
1090 break;
1091
1092 case SO_PASSCRED:
1093 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1094 break;
1095
1096 case SO_PEERCRED:
1097 {
1098 struct ucred peercred;
1099 if (len > sizeof(peercred))
1100 len = sizeof(peercred);
1101 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1102 if (copy_to_user(optval, &peercred, len))
1103 return -EFAULT;
1104 goto lenout;
1105 }
1106
1107 case SO_PEERNAME:
1108 {
1109 char address[128];
1110
1111 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1112 return -ENOTCONN;
1113 if (lv < len)
1114 return -EINVAL;
1115 if (copy_to_user(optval, address, len))
1116 return -EFAULT;
1117 goto lenout;
1118 }
1119
1120 /* Dubious BSD thing... Probably nobody even uses it, but
1121 * the UNIX standard wants it for whatever reason... -DaveM
1122 */
1123 case SO_ACCEPTCONN:
1124 v.val = sk->sk_state == TCP_LISTEN;
1125 break;
1126
1127 case SO_PASSSEC:
1128 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1129 break;
1130
1131 case SO_PEERSEC:
1132 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1133
1134 case SO_MARK:
1135 v.val = sk->sk_mark;
1136 break;
1137
1138 case SO_RXQ_OVFL:
1139 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1140 break;
1141
1142 case SO_WIFI_STATUS:
1143 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1144 break;
1145
1146 case SO_PEEK_OFF:
1147 if (!sock->ops->set_peek_off)
1148 return -EOPNOTSUPP;
1149
1150 v.val = sk->sk_peek_off;
1151 break;
1152 case SO_NOFCS:
1153 v.val = sock_flag(sk, SOCK_NOFCS);
1154 break;
1155
1156 case SO_BINDTODEVICE:
1157 return sock_getbindtodevice(sk, optval, optlen, len);
1158
1159 case SO_GET_FILTER:
1160 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1161 if (len < 0)
1162 return len;
1163
1164 goto lenout;
1165
1166 case SO_LOCK_FILTER:
1167 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1168 break;
1169
1170 case SO_SELECT_ERR_QUEUE:
1171 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1172 break;
1173
1174 #ifdef CONFIG_NET_RX_BUSY_POLL
1175 case SO_BUSY_POLL:
1176 v.val = sk->sk_ll_usec;
1177 break;
1178 #endif
1179
1180 case SO_MAX_PACING_RATE:
1181 v.val = sk->sk_max_pacing_rate;
1182 break;
1183
1184 default:
1185 return -ENOPROTOOPT;
1186 }
1187
1188 if (len > lv)
1189 len = lv;
1190 if (copy_to_user(optval, &v, len))
1191 return -EFAULT;
1192 lenout:
1193 if (put_user(len, optlen))
1194 return -EFAULT;
1195 return 0;
1196 }
1197
1198 /*
1199 * Initialize an sk_lock.
1200 *
1201 * (We also register the sk_lock with the lock validator.)
1202 */
1203 static inline void sock_lock_init(struct sock *sk)
1204 {
1205 sock_lock_init_class_and_name(sk,
1206 af_family_slock_key_strings[sk->sk_family],
1207 af_family_slock_keys + sk->sk_family,
1208 af_family_key_strings[sk->sk_family],
1209 af_family_keys + sk->sk_family);
1210 }
1211
1212 /*
1213 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1214 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1215 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1216 */
1217 static void sock_copy(struct sock *nsk, const struct sock *osk)
1218 {
1219 #ifdef CONFIG_SECURITY_NETWORK
1220 void *sptr = nsk->sk_security;
1221 #endif
1222 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1223
1224 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1225 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1226
1227 #ifdef CONFIG_SECURITY_NETWORK
1228 nsk->sk_security = sptr;
1229 security_sk_clone(osk, nsk);
1230 #endif
1231 }
1232
1233 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1234 {
1235 unsigned long nulls1, nulls2;
1236
1237 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1238 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1239 if (nulls1 > nulls2)
1240 swap(nulls1, nulls2);
1241
1242 if (nulls1 != 0)
1243 memset((char *)sk, 0, nulls1);
1244 memset((char *)sk + nulls1 + sizeof(void *), 0,
1245 nulls2 - nulls1 - sizeof(void *));
1246 memset((char *)sk + nulls2 + sizeof(void *), 0,
1247 size - nulls2 - sizeof(void *));
1248 }
1249 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1250
1251 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1252 int family)
1253 {
1254 struct sock *sk;
1255 struct kmem_cache *slab;
1256
1257 slab = prot->slab;
1258 if (slab != NULL) {
1259 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1260 if (!sk)
1261 return sk;
1262 if (priority & __GFP_ZERO) {
1263 if (prot->clear_sk)
1264 prot->clear_sk(sk, prot->obj_size);
1265 else
1266 sk_prot_clear_nulls(sk, prot->obj_size);
1267 }
1268 } else
1269 sk = kmalloc(prot->obj_size, priority);
1270
1271 if (sk != NULL) {
1272 kmemcheck_annotate_bitfield(sk, flags);
1273
1274 if (security_sk_alloc(sk, family, priority))
1275 goto out_free;
1276
1277 if (!try_module_get(prot->owner))
1278 goto out_free_sec;
1279 sk_tx_queue_clear(sk);
1280 }
1281
1282 return sk;
1283
1284 out_free_sec:
1285 security_sk_free(sk);
1286 out_free:
1287 if (slab != NULL)
1288 kmem_cache_free(slab, sk);
1289 else
1290 kfree(sk);
1291 return NULL;
1292 }
1293
1294 static void sk_prot_free(struct proto *prot, struct sock *sk)
1295 {
1296 struct kmem_cache *slab;
1297 struct module *owner;
1298
1299 owner = prot->owner;
1300 slab = prot->slab;
1301
1302 security_sk_free(sk);
1303 if (slab != NULL)
1304 kmem_cache_free(slab, sk);
1305 else
1306 kfree(sk);
1307 module_put(owner);
1308 }
1309
1310 #if IS_ENABLED(CONFIG_NET_CLS_CGROUP)
1311 void sock_update_classid(struct sock *sk)
1312 {
1313 u32 classid;
1314
1315 classid = task_cls_classid(current);
1316 if (classid != sk->sk_classid)
1317 sk->sk_classid = classid;
1318 }
1319 EXPORT_SYMBOL(sock_update_classid);
1320 #endif
1321
1322 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP)
1323 void sock_update_netprioidx(struct sock *sk)
1324 {
1325 if (in_interrupt())
1326 return;
1327
1328 sk->sk_cgrp_prioidx = task_netprioidx(current);
1329 }
1330 EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1331 #endif
1332
1333 /**
1334 * sk_alloc - All socket objects are allocated here
1335 * @net: the applicable net namespace
1336 * @family: protocol family
1337 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1338 * @prot: struct proto associated with this new sock instance
1339 */
1340 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1341 struct proto *prot)
1342 {
1343 struct sock *sk;
1344
1345 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1346 if (sk) {
1347 sk->sk_family = family;
1348 /*
1349 * See comment in struct sock definition to understand
1350 * why we need sk_prot_creator -acme
1351 */
1352 sk->sk_prot = sk->sk_prot_creator = prot;
1353 sock_lock_init(sk);
1354 sock_net_set(sk, get_net(net));
1355 atomic_set(&sk->sk_wmem_alloc, 1);
1356
1357 sock_update_classid(sk);
1358 sock_update_netprioidx(sk);
1359 }
1360
1361 return sk;
1362 }
1363 EXPORT_SYMBOL(sk_alloc);
1364
1365 static void __sk_free(struct sock *sk)
1366 {
1367 struct sk_filter *filter;
1368
1369 if (sk->sk_destruct)
1370 sk->sk_destruct(sk);
1371
1372 filter = rcu_dereference_check(sk->sk_filter,
1373 atomic_read(&sk->sk_wmem_alloc) == 0);
1374 if (filter) {
1375 sk_filter_uncharge(sk, filter);
1376 RCU_INIT_POINTER(sk->sk_filter, NULL);
1377 }
1378
1379 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1380
1381 if (atomic_read(&sk->sk_omem_alloc))
1382 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1383 __func__, atomic_read(&sk->sk_omem_alloc));
1384
1385 if (sk->sk_peer_cred)
1386 put_cred(sk->sk_peer_cred);
1387 put_pid(sk->sk_peer_pid);
1388 put_net(sock_net(sk));
1389 sk_prot_free(sk->sk_prot_creator, sk);
1390 }
1391
1392 void sk_free(struct sock *sk)
1393 {
1394 /*
1395 * We subtract one from sk_wmem_alloc and can know if
1396 * some packets are still in some tx queue.
1397 * If not null, sock_wfree() will call __sk_free(sk) later
1398 */
1399 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1400 __sk_free(sk);
1401 }
1402 EXPORT_SYMBOL(sk_free);
1403
1404 /*
1405 * Last sock_put should drop reference to sk->sk_net. It has already
1406 * been dropped in sk_change_net. Taking reference to stopping namespace
1407 * is not an option.
1408 * Take reference to a socket to remove it from hash _alive_ and after that
1409 * destroy it in the context of init_net.
1410 */
1411 void sk_release_kernel(struct sock *sk)
1412 {
1413 if (sk == NULL || sk->sk_socket == NULL)
1414 return;
1415
1416 sock_hold(sk);
1417 sock_release(sk->sk_socket);
1418 release_net(sock_net(sk));
1419 sock_net_set(sk, get_net(&init_net));
1420 sock_put(sk);
1421 }
1422 EXPORT_SYMBOL(sk_release_kernel);
1423
1424 static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1425 {
1426 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1427 sock_update_memcg(newsk);
1428 }
1429
1430 /**
1431 * sk_clone_lock - clone a socket, and lock its clone
1432 * @sk: the socket to clone
1433 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1434 *
1435 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1436 */
1437 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1438 {
1439 struct sock *newsk;
1440
1441 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1442 if (newsk != NULL) {
1443 struct sk_filter *filter;
1444
1445 sock_copy(newsk, sk);
1446
1447 /* SANITY */
1448 get_net(sock_net(newsk));
1449 sk_node_init(&newsk->sk_node);
1450 sock_lock_init(newsk);
1451 bh_lock_sock(newsk);
1452 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1453 newsk->sk_backlog.len = 0;
1454
1455 atomic_set(&newsk->sk_rmem_alloc, 0);
1456 /*
1457 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1458 */
1459 atomic_set(&newsk->sk_wmem_alloc, 1);
1460 atomic_set(&newsk->sk_omem_alloc, 0);
1461 skb_queue_head_init(&newsk->sk_receive_queue);
1462 skb_queue_head_init(&newsk->sk_write_queue);
1463 #ifdef CONFIG_NET_DMA
1464 skb_queue_head_init(&newsk->sk_async_wait_queue);
1465 #endif
1466
1467 spin_lock_init(&newsk->sk_dst_lock);
1468 rwlock_init(&newsk->sk_callback_lock);
1469 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1470 af_callback_keys + newsk->sk_family,
1471 af_family_clock_key_strings[newsk->sk_family]);
1472
1473 newsk->sk_dst_cache = NULL;
1474 newsk->sk_wmem_queued = 0;
1475 newsk->sk_forward_alloc = 0;
1476 newsk->sk_send_head = NULL;
1477 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1478
1479 sock_reset_flag(newsk, SOCK_DONE);
1480 skb_queue_head_init(&newsk->sk_error_queue);
1481
1482 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1483 if (filter != NULL)
1484 sk_filter_charge(newsk, filter);
1485
1486 if (unlikely(xfrm_sk_clone_policy(newsk))) {
1487 /* It is still raw copy of parent, so invalidate
1488 * destructor and make plain sk_free() */
1489 newsk->sk_destruct = NULL;
1490 bh_unlock_sock(newsk);
1491 sk_free(newsk);
1492 newsk = NULL;
1493 goto out;
1494 }
1495
1496 newsk->sk_err = 0;
1497 newsk->sk_priority = 0;
1498 /*
1499 * Before updating sk_refcnt, we must commit prior changes to memory
1500 * (Documentation/RCU/rculist_nulls.txt for details)
1501 */
1502 smp_wmb();
1503 atomic_set(&newsk->sk_refcnt, 2);
1504
1505 /*
1506 * Increment the counter in the same struct proto as the master
1507 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1508 * is the same as sk->sk_prot->socks, as this field was copied
1509 * with memcpy).
1510 *
1511 * This _changes_ the previous behaviour, where
1512 * tcp_create_openreq_child always was incrementing the
1513 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1514 * to be taken into account in all callers. -acme
1515 */
1516 sk_refcnt_debug_inc(newsk);
1517 sk_set_socket(newsk, NULL);
1518 newsk->sk_wq = NULL;
1519
1520 sk_update_clone(sk, newsk);
1521
1522 if (newsk->sk_prot->sockets_allocated)
1523 sk_sockets_allocated_inc(newsk);
1524
1525 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1526 net_enable_timestamp();
1527 }
1528 out:
1529 return newsk;
1530 }
1531 EXPORT_SYMBOL_GPL(sk_clone_lock);
1532
1533 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1534 {
1535 __sk_dst_set(sk, dst);
1536 sk->sk_route_caps = dst->dev->features;
1537 if (sk->sk_route_caps & NETIF_F_GSO)
1538 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1539 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1540 if (sk_can_gso(sk)) {
1541 if (dst->header_len) {
1542 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1543 } else {
1544 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1545 sk->sk_gso_max_size = dst->dev->gso_max_size;
1546 sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1547 }
1548 }
1549 }
1550 EXPORT_SYMBOL_GPL(sk_setup_caps);
1551
1552 /*
1553 * Simple resource managers for sockets.
1554 */
1555
1556
1557 /*
1558 * Write buffer destructor automatically called from kfree_skb.
1559 */
1560 void sock_wfree(struct sk_buff *skb)
1561 {
1562 struct sock *sk = skb->sk;
1563 unsigned int len = skb->truesize;
1564
1565 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1566 /*
1567 * Keep a reference on sk_wmem_alloc, this will be released
1568 * after sk_write_space() call
1569 */
1570 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1571 sk->sk_write_space(sk);
1572 len = 1;
1573 }
1574 /*
1575 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1576 * could not do because of in-flight packets
1577 */
1578 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1579 __sk_free(sk);
1580 }
1581 EXPORT_SYMBOL(sock_wfree);
1582
1583 void skb_orphan_partial(struct sk_buff *skb)
1584 {
1585 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1586 * so we do not completely orphan skb, but transfert all
1587 * accounted bytes but one, to avoid unexpected reorders.
1588 */
1589 if (skb->destructor == sock_wfree
1590 #ifdef CONFIG_INET
1591 || skb->destructor == tcp_wfree
1592 #endif
1593 ) {
1594 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1595 skb->truesize = 1;
1596 } else {
1597 skb_orphan(skb);
1598 }
1599 }
1600 EXPORT_SYMBOL(skb_orphan_partial);
1601
1602 /*
1603 * Read buffer destructor automatically called from kfree_skb.
1604 */
1605 void sock_rfree(struct sk_buff *skb)
1606 {
1607 struct sock *sk = skb->sk;
1608 unsigned int len = skb->truesize;
1609
1610 atomic_sub(len, &sk->sk_rmem_alloc);
1611 sk_mem_uncharge(sk, len);
1612 }
1613 EXPORT_SYMBOL(sock_rfree);
1614
1615 void sock_edemux(struct sk_buff *skb)
1616 {
1617 struct sock *sk = skb->sk;
1618
1619 #ifdef CONFIG_INET
1620 if (sk->sk_state == TCP_TIME_WAIT)
1621 inet_twsk_put(inet_twsk(sk));
1622 else
1623 #endif
1624 sock_put(sk);
1625 }
1626 EXPORT_SYMBOL(sock_edemux);
1627
1628 kuid_t sock_i_uid(struct sock *sk)
1629 {
1630 kuid_t uid;
1631
1632 read_lock_bh(&sk->sk_callback_lock);
1633 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1634 read_unlock_bh(&sk->sk_callback_lock);
1635 return uid;
1636 }
1637 EXPORT_SYMBOL(sock_i_uid);
1638
1639 unsigned long sock_i_ino(struct sock *sk)
1640 {
1641 unsigned long ino;
1642
1643 read_lock_bh(&sk->sk_callback_lock);
1644 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1645 read_unlock_bh(&sk->sk_callback_lock);
1646 return ino;
1647 }
1648 EXPORT_SYMBOL(sock_i_ino);
1649
1650 /*
1651 * Allocate a skb from the socket's send buffer.
1652 */
1653 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1654 gfp_t priority)
1655 {
1656 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1657 struct sk_buff *skb = alloc_skb(size, priority);
1658 if (skb) {
1659 skb_set_owner_w(skb, sk);
1660 return skb;
1661 }
1662 }
1663 return NULL;
1664 }
1665 EXPORT_SYMBOL(sock_wmalloc);
1666
1667 /*
1668 * Allocate a memory block from the socket's option memory buffer.
1669 */
1670 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1671 {
1672 if ((unsigned int)size <= sysctl_optmem_max &&
1673 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1674 void *mem;
1675 /* First do the add, to avoid the race if kmalloc
1676 * might sleep.
1677 */
1678 atomic_add(size, &sk->sk_omem_alloc);
1679 mem = kmalloc(size, priority);
1680 if (mem)
1681 return mem;
1682 atomic_sub(size, &sk->sk_omem_alloc);
1683 }
1684 return NULL;
1685 }
1686 EXPORT_SYMBOL(sock_kmalloc);
1687
1688 /*
1689 * Free an option memory block.
1690 */
1691 void sock_kfree_s(struct sock *sk, void *mem, int size)
1692 {
1693 kfree(mem);
1694 atomic_sub(size, &sk->sk_omem_alloc);
1695 }
1696 EXPORT_SYMBOL(sock_kfree_s);
1697
1698 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1699 I think, these locks should be removed for datagram sockets.
1700 */
1701 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1702 {
1703 DEFINE_WAIT(wait);
1704
1705 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1706 for (;;) {
1707 if (!timeo)
1708 break;
1709 if (signal_pending(current))
1710 break;
1711 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1712 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1713 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1714 break;
1715 if (sk->sk_shutdown & SEND_SHUTDOWN)
1716 break;
1717 if (sk->sk_err)
1718 break;
1719 timeo = schedule_timeout(timeo);
1720 }
1721 finish_wait(sk_sleep(sk), &wait);
1722 return timeo;
1723 }
1724
1725
1726 /*
1727 * Generic send/receive buffer handlers
1728 */
1729
1730 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1731 unsigned long data_len, int noblock,
1732 int *errcode, int max_page_order)
1733 {
1734 struct sk_buff *skb = NULL;
1735 unsigned long chunk;
1736 gfp_t gfp_mask;
1737 long timeo;
1738 int err;
1739 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1740 struct page *page;
1741 int i;
1742
1743 err = -EMSGSIZE;
1744 if (npages > MAX_SKB_FRAGS)
1745 goto failure;
1746
1747 timeo = sock_sndtimeo(sk, noblock);
1748 while (!skb) {
1749 err = sock_error(sk);
1750 if (err != 0)
1751 goto failure;
1752
1753 err = -EPIPE;
1754 if (sk->sk_shutdown & SEND_SHUTDOWN)
1755 goto failure;
1756
1757 if (atomic_read(&sk->sk_wmem_alloc) >= sk->sk_sndbuf) {
1758 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1759 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1760 err = -EAGAIN;
1761 if (!timeo)
1762 goto failure;
1763 if (signal_pending(current))
1764 goto interrupted;
1765 timeo = sock_wait_for_wmem(sk, timeo);
1766 continue;
1767 }
1768
1769 err = -ENOBUFS;
1770 gfp_mask = sk->sk_allocation;
1771 if (gfp_mask & __GFP_WAIT)
1772 gfp_mask |= __GFP_REPEAT;
1773
1774 skb = alloc_skb(header_len, gfp_mask);
1775 if (!skb)
1776 goto failure;
1777
1778 skb->truesize += data_len;
1779
1780 for (i = 0; npages > 0; i++) {
1781 int order = max_page_order;
1782
1783 while (order) {
1784 if (npages >= 1 << order) {
1785 page = alloc_pages(sk->sk_allocation |
1786 __GFP_COMP | __GFP_NOWARN,
1787 order);
1788 if (page)
1789 goto fill_page;
1790 }
1791 order--;
1792 }
1793 page = alloc_page(sk->sk_allocation);
1794 if (!page)
1795 goto failure;
1796 fill_page:
1797 chunk = min_t(unsigned long, data_len,
1798 PAGE_SIZE << order);
1799 skb_fill_page_desc(skb, i, page, 0, chunk);
1800 data_len -= chunk;
1801 npages -= 1 << order;
1802 }
1803 }
1804
1805 skb_set_owner_w(skb, sk);
1806 return skb;
1807
1808 interrupted:
1809 err = sock_intr_errno(timeo);
1810 failure:
1811 kfree_skb(skb);
1812 *errcode = err;
1813 return NULL;
1814 }
1815 EXPORT_SYMBOL(sock_alloc_send_pskb);
1816
1817 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1818 int noblock, int *errcode)
1819 {
1820 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1821 }
1822 EXPORT_SYMBOL(sock_alloc_send_skb);
1823
1824 /* On 32bit arches, an skb frag is limited to 2^15 */
1825 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1826
1827 /**
1828 * skb_page_frag_refill - check that a page_frag contains enough room
1829 * @sz: minimum size of the fragment we want to get
1830 * @pfrag: pointer to page_frag
1831 * @prio: priority for memory allocation
1832 *
1833 * Note: While this allocator tries to use high order pages, there is
1834 * no guarantee that allocations succeed. Therefore, @sz MUST be
1835 * less or equal than PAGE_SIZE.
1836 */
1837 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio)
1838 {
1839 int order;
1840
1841 if (pfrag->page) {
1842 if (atomic_read(&pfrag->page->_count) == 1) {
1843 pfrag->offset = 0;
1844 return true;
1845 }
1846 if (pfrag->offset + sz <= pfrag->size)
1847 return true;
1848 put_page(pfrag->page);
1849 }
1850
1851 /* We restrict high order allocations to users that can afford to wait */
1852 order = (prio & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0;
1853
1854 do {
1855 gfp_t gfp = prio;
1856
1857 if (order)
1858 gfp |= __GFP_COMP | __GFP_NOWARN;
1859 pfrag->page = alloc_pages(gfp, order);
1860 if (likely(pfrag->page)) {
1861 pfrag->offset = 0;
1862 pfrag->size = PAGE_SIZE << order;
1863 return true;
1864 }
1865 } while (--order >= 0);
1866
1867 return false;
1868 }
1869 EXPORT_SYMBOL(skb_page_frag_refill);
1870
1871 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1872 {
1873 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1874 return true;
1875
1876 sk_enter_memory_pressure(sk);
1877 sk_stream_moderate_sndbuf(sk);
1878 return false;
1879 }
1880 EXPORT_SYMBOL(sk_page_frag_refill);
1881
1882 static void __lock_sock(struct sock *sk)
1883 __releases(&sk->sk_lock.slock)
1884 __acquires(&sk->sk_lock.slock)
1885 {
1886 DEFINE_WAIT(wait);
1887
1888 for (;;) {
1889 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1890 TASK_UNINTERRUPTIBLE);
1891 spin_unlock_bh(&sk->sk_lock.slock);
1892 schedule();
1893 spin_lock_bh(&sk->sk_lock.slock);
1894 if (!sock_owned_by_user(sk))
1895 break;
1896 }
1897 finish_wait(&sk->sk_lock.wq, &wait);
1898 }
1899
1900 static void __release_sock(struct sock *sk)
1901 __releases(&sk->sk_lock.slock)
1902 __acquires(&sk->sk_lock.slock)
1903 {
1904 struct sk_buff *skb = sk->sk_backlog.head;
1905
1906 do {
1907 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1908 bh_unlock_sock(sk);
1909
1910 do {
1911 struct sk_buff *next = skb->next;
1912
1913 prefetch(next);
1914 WARN_ON_ONCE(skb_dst_is_noref(skb));
1915 skb->next = NULL;
1916 sk_backlog_rcv(sk, skb);
1917
1918 /*
1919 * We are in process context here with softirqs
1920 * disabled, use cond_resched_softirq() to preempt.
1921 * This is safe to do because we've taken the backlog
1922 * queue private:
1923 */
1924 cond_resched_softirq();
1925
1926 skb = next;
1927 } while (skb != NULL);
1928
1929 bh_lock_sock(sk);
1930 } while ((skb = sk->sk_backlog.head) != NULL);
1931
1932 /*
1933 * Doing the zeroing here guarantee we can not loop forever
1934 * while a wild producer attempts to flood us.
1935 */
1936 sk->sk_backlog.len = 0;
1937 }
1938
1939 /**
1940 * sk_wait_data - wait for data to arrive at sk_receive_queue
1941 * @sk: sock to wait on
1942 * @timeo: for how long
1943 *
1944 * Now socket state including sk->sk_err is changed only under lock,
1945 * hence we may omit checks after joining wait queue.
1946 * We check receive queue before schedule() only as optimization;
1947 * it is very likely that release_sock() added new data.
1948 */
1949 int sk_wait_data(struct sock *sk, long *timeo)
1950 {
1951 int rc;
1952 DEFINE_WAIT(wait);
1953
1954 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1955 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1956 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1957 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1958 finish_wait(sk_sleep(sk), &wait);
1959 return rc;
1960 }
1961 EXPORT_SYMBOL(sk_wait_data);
1962
1963 /**
1964 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1965 * @sk: socket
1966 * @size: memory size to allocate
1967 * @kind: allocation type
1968 *
1969 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1970 * rmem allocation. This function assumes that protocols which have
1971 * memory_pressure use sk_wmem_queued as write buffer accounting.
1972 */
1973 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1974 {
1975 struct proto *prot = sk->sk_prot;
1976 int amt = sk_mem_pages(size);
1977 long allocated;
1978 int parent_status = UNDER_LIMIT;
1979
1980 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1981
1982 allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1983
1984 /* Under limit. */
1985 if (parent_status == UNDER_LIMIT &&
1986 allocated <= sk_prot_mem_limits(sk, 0)) {
1987 sk_leave_memory_pressure(sk);
1988 return 1;
1989 }
1990
1991 /* Under pressure. (we or our parents) */
1992 if ((parent_status > SOFT_LIMIT) ||
1993 allocated > sk_prot_mem_limits(sk, 1))
1994 sk_enter_memory_pressure(sk);
1995
1996 /* Over hard limit (we or our parents) */
1997 if ((parent_status == OVER_LIMIT) ||
1998 (allocated > sk_prot_mem_limits(sk, 2)))
1999 goto suppress_allocation;
2000
2001 /* guarantee minimum buffer size under pressure */
2002 if (kind == SK_MEM_RECV) {
2003 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2004 return 1;
2005
2006 } else { /* SK_MEM_SEND */
2007 if (sk->sk_type == SOCK_STREAM) {
2008 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2009 return 1;
2010 } else if (atomic_read(&sk->sk_wmem_alloc) <
2011 prot->sysctl_wmem[0])
2012 return 1;
2013 }
2014
2015 if (sk_has_memory_pressure(sk)) {
2016 int alloc;
2017
2018 if (!sk_under_memory_pressure(sk))
2019 return 1;
2020 alloc = sk_sockets_allocated_read_positive(sk);
2021 if (sk_prot_mem_limits(sk, 2) > alloc *
2022 sk_mem_pages(sk->sk_wmem_queued +
2023 atomic_read(&sk->sk_rmem_alloc) +
2024 sk->sk_forward_alloc))
2025 return 1;
2026 }
2027
2028 suppress_allocation:
2029
2030 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2031 sk_stream_moderate_sndbuf(sk);
2032
2033 /* Fail only if socket is _under_ its sndbuf.
2034 * In this case we cannot block, so that we have to fail.
2035 */
2036 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2037 return 1;
2038 }
2039
2040 trace_sock_exceed_buf_limit(sk, prot, allocated);
2041
2042 /* Alas. Undo changes. */
2043 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2044
2045 sk_memory_allocated_sub(sk, amt);
2046
2047 return 0;
2048 }
2049 EXPORT_SYMBOL(__sk_mem_schedule);
2050
2051 /**
2052 * __sk_reclaim - reclaim memory_allocated
2053 * @sk: socket
2054 */
2055 void __sk_mem_reclaim(struct sock *sk)
2056 {
2057 sk_memory_allocated_sub(sk,
2058 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
2059 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
2060
2061 if (sk_under_memory_pressure(sk) &&
2062 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2063 sk_leave_memory_pressure(sk);
2064 }
2065 EXPORT_SYMBOL(__sk_mem_reclaim);
2066
2067
2068 /*
2069 * Set of default routines for initialising struct proto_ops when
2070 * the protocol does not support a particular function. In certain
2071 * cases where it makes no sense for a protocol to have a "do nothing"
2072 * function, some default processing is provided.
2073 */
2074
2075 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2076 {
2077 return -EOPNOTSUPP;
2078 }
2079 EXPORT_SYMBOL(sock_no_bind);
2080
2081 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2082 int len, int flags)
2083 {
2084 return -EOPNOTSUPP;
2085 }
2086 EXPORT_SYMBOL(sock_no_connect);
2087
2088 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2089 {
2090 return -EOPNOTSUPP;
2091 }
2092 EXPORT_SYMBOL(sock_no_socketpair);
2093
2094 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2095 {
2096 return -EOPNOTSUPP;
2097 }
2098 EXPORT_SYMBOL(sock_no_accept);
2099
2100 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2101 int *len, int peer)
2102 {
2103 return -EOPNOTSUPP;
2104 }
2105 EXPORT_SYMBOL(sock_no_getname);
2106
2107 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2108 {
2109 return 0;
2110 }
2111 EXPORT_SYMBOL(sock_no_poll);
2112
2113 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2114 {
2115 return -EOPNOTSUPP;
2116 }
2117 EXPORT_SYMBOL(sock_no_ioctl);
2118
2119 int sock_no_listen(struct socket *sock, int backlog)
2120 {
2121 return -EOPNOTSUPP;
2122 }
2123 EXPORT_SYMBOL(sock_no_listen);
2124
2125 int sock_no_shutdown(struct socket *sock, int how)
2126 {
2127 return -EOPNOTSUPP;
2128 }
2129 EXPORT_SYMBOL(sock_no_shutdown);
2130
2131 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2132 char __user *optval, unsigned int optlen)
2133 {
2134 return -EOPNOTSUPP;
2135 }
2136 EXPORT_SYMBOL(sock_no_setsockopt);
2137
2138 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2139 char __user *optval, int __user *optlen)
2140 {
2141 return -EOPNOTSUPP;
2142 }
2143 EXPORT_SYMBOL(sock_no_getsockopt);
2144
2145 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2146 size_t len)
2147 {
2148 return -EOPNOTSUPP;
2149 }
2150 EXPORT_SYMBOL(sock_no_sendmsg);
2151
2152 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2153 size_t len, int flags)
2154 {
2155 return -EOPNOTSUPP;
2156 }
2157 EXPORT_SYMBOL(sock_no_recvmsg);
2158
2159 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2160 {
2161 /* Mirror missing mmap method error code */
2162 return -ENODEV;
2163 }
2164 EXPORT_SYMBOL(sock_no_mmap);
2165
2166 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2167 {
2168 ssize_t res;
2169 struct msghdr msg = {.msg_flags = flags};
2170 struct kvec iov;
2171 char *kaddr = kmap(page);
2172 iov.iov_base = kaddr + offset;
2173 iov.iov_len = size;
2174 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2175 kunmap(page);
2176 return res;
2177 }
2178 EXPORT_SYMBOL(sock_no_sendpage);
2179
2180 /*
2181 * Default Socket Callbacks
2182 */
2183
2184 static void sock_def_wakeup(struct sock *sk)
2185 {
2186 struct socket_wq *wq;
2187
2188 rcu_read_lock();
2189 wq = rcu_dereference(sk->sk_wq);
2190 if (wq_has_sleeper(wq))
2191 wake_up_interruptible_all(&wq->wait);
2192 rcu_read_unlock();
2193 }
2194
2195 static void sock_def_error_report(struct sock *sk)
2196 {
2197 struct socket_wq *wq;
2198
2199 rcu_read_lock();
2200 wq = rcu_dereference(sk->sk_wq);
2201 if (wq_has_sleeper(wq))
2202 wake_up_interruptible_poll(&wq->wait, POLLERR);
2203 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2204 rcu_read_unlock();
2205 }
2206
2207 static void sock_def_readable(struct sock *sk, int len)
2208 {
2209 struct socket_wq *wq;
2210
2211 rcu_read_lock();
2212 wq = rcu_dereference(sk->sk_wq);
2213 if (wq_has_sleeper(wq))
2214 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2215 POLLRDNORM | POLLRDBAND);
2216 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2217 rcu_read_unlock();
2218 }
2219
2220 static void sock_def_write_space(struct sock *sk)
2221 {
2222 struct socket_wq *wq;
2223
2224 rcu_read_lock();
2225
2226 /* Do not wake up a writer until he can make "significant"
2227 * progress. --DaveM
2228 */
2229 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2230 wq = rcu_dereference(sk->sk_wq);
2231 if (wq_has_sleeper(wq))
2232 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2233 POLLWRNORM | POLLWRBAND);
2234
2235 /* Should agree with poll, otherwise some programs break */
2236 if (sock_writeable(sk))
2237 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2238 }
2239
2240 rcu_read_unlock();
2241 }
2242
2243 static void sock_def_destruct(struct sock *sk)
2244 {
2245 kfree(sk->sk_protinfo);
2246 }
2247
2248 void sk_send_sigurg(struct sock *sk)
2249 {
2250 if (sk->sk_socket && sk->sk_socket->file)
2251 if (send_sigurg(&sk->sk_socket->file->f_owner))
2252 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2253 }
2254 EXPORT_SYMBOL(sk_send_sigurg);
2255
2256 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2257 unsigned long expires)
2258 {
2259 if (!mod_timer(timer, expires))
2260 sock_hold(sk);
2261 }
2262 EXPORT_SYMBOL(sk_reset_timer);
2263
2264 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2265 {
2266 if (del_timer(timer))
2267 __sock_put(sk);
2268 }
2269 EXPORT_SYMBOL(sk_stop_timer);
2270
2271 void sock_init_data(struct socket *sock, struct sock *sk)
2272 {
2273 skb_queue_head_init(&sk->sk_receive_queue);
2274 skb_queue_head_init(&sk->sk_write_queue);
2275 skb_queue_head_init(&sk->sk_error_queue);
2276 #ifdef CONFIG_NET_DMA
2277 skb_queue_head_init(&sk->sk_async_wait_queue);
2278 #endif
2279
2280 sk->sk_send_head = NULL;
2281
2282 init_timer(&sk->sk_timer);
2283
2284 sk->sk_allocation = GFP_KERNEL;
2285 sk->sk_rcvbuf = sysctl_rmem_default;
2286 sk->sk_sndbuf = sysctl_wmem_default;
2287 sk->sk_state = TCP_CLOSE;
2288 sk_set_socket(sk, sock);
2289
2290 sock_set_flag(sk, SOCK_ZAPPED);
2291
2292 if (sock) {
2293 sk->sk_type = sock->type;
2294 sk->sk_wq = sock->wq;
2295 sock->sk = sk;
2296 } else
2297 sk->sk_wq = NULL;
2298
2299 spin_lock_init(&sk->sk_dst_lock);
2300 rwlock_init(&sk->sk_callback_lock);
2301 lockdep_set_class_and_name(&sk->sk_callback_lock,
2302 af_callback_keys + sk->sk_family,
2303 af_family_clock_key_strings[sk->sk_family]);
2304
2305 sk->sk_state_change = sock_def_wakeup;
2306 sk->sk_data_ready = sock_def_readable;
2307 sk->sk_write_space = sock_def_write_space;
2308 sk->sk_error_report = sock_def_error_report;
2309 sk->sk_destruct = sock_def_destruct;
2310
2311 sk->sk_frag.page = NULL;
2312 sk->sk_frag.offset = 0;
2313 sk->sk_peek_off = -1;
2314
2315 sk->sk_peer_pid = NULL;
2316 sk->sk_peer_cred = NULL;
2317 sk->sk_write_pending = 0;
2318 sk->sk_rcvlowat = 1;
2319 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2320 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2321
2322 sk->sk_stamp = ktime_set(-1L, 0);
2323
2324 #ifdef CONFIG_NET_RX_BUSY_POLL
2325 sk->sk_napi_id = 0;
2326 sk->sk_ll_usec = sysctl_net_busy_read;
2327 #endif
2328
2329 sk->sk_max_pacing_rate = ~0U;
2330 sk->sk_pacing_rate = ~0U;
2331 /*
2332 * Before updating sk_refcnt, we must commit prior changes to memory
2333 * (Documentation/RCU/rculist_nulls.txt for details)
2334 */
2335 smp_wmb();
2336 atomic_set(&sk->sk_refcnt, 1);
2337 atomic_set(&sk->sk_drops, 0);
2338 }
2339 EXPORT_SYMBOL(sock_init_data);
2340
2341 void lock_sock_nested(struct sock *sk, int subclass)
2342 {
2343 might_sleep();
2344 spin_lock_bh(&sk->sk_lock.slock);
2345 if (sk->sk_lock.owned)
2346 __lock_sock(sk);
2347 sk->sk_lock.owned = 1;
2348 spin_unlock(&sk->sk_lock.slock);
2349 /*
2350 * The sk_lock has mutex_lock() semantics here:
2351 */
2352 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2353 local_bh_enable();
2354 }
2355 EXPORT_SYMBOL(lock_sock_nested);
2356
2357 void release_sock(struct sock *sk)
2358 {
2359 /*
2360 * The sk_lock has mutex_unlock() semantics:
2361 */
2362 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2363
2364 spin_lock_bh(&sk->sk_lock.slock);
2365 if (sk->sk_backlog.tail)
2366 __release_sock(sk);
2367
2368 if (sk->sk_prot->release_cb)
2369 sk->sk_prot->release_cb(sk);
2370
2371 sk->sk_lock.owned = 0;
2372 if (waitqueue_active(&sk->sk_lock.wq))
2373 wake_up(&sk->sk_lock.wq);
2374 spin_unlock_bh(&sk->sk_lock.slock);
2375 }
2376 EXPORT_SYMBOL(release_sock);
2377
2378 /**
2379 * lock_sock_fast - fast version of lock_sock
2380 * @sk: socket
2381 *
2382 * This version should be used for very small section, where process wont block
2383 * return false if fast path is taken
2384 * sk_lock.slock locked, owned = 0, BH disabled
2385 * return true if slow path is taken
2386 * sk_lock.slock unlocked, owned = 1, BH enabled
2387 */
2388 bool lock_sock_fast(struct sock *sk)
2389 {
2390 might_sleep();
2391 spin_lock_bh(&sk->sk_lock.slock);
2392
2393 if (!sk->sk_lock.owned)
2394 /*
2395 * Note : We must disable BH
2396 */
2397 return false;
2398
2399 __lock_sock(sk);
2400 sk->sk_lock.owned = 1;
2401 spin_unlock(&sk->sk_lock.slock);
2402 /*
2403 * The sk_lock has mutex_lock() semantics here:
2404 */
2405 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2406 local_bh_enable();
2407 return true;
2408 }
2409 EXPORT_SYMBOL(lock_sock_fast);
2410
2411 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2412 {
2413 struct timeval tv;
2414 if (!sock_flag(sk, SOCK_TIMESTAMP))
2415 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2416 tv = ktime_to_timeval(sk->sk_stamp);
2417 if (tv.tv_sec == -1)
2418 return -ENOENT;
2419 if (tv.tv_sec == 0) {
2420 sk->sk_stamp = ktime_get_real();
2421 tv = ktime_to_timeval(sk->sk_stamp);
2422 }
2423 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2424 }
2425 EXPORT_SYMBOL(sock_get_timestamp);
2426
2427 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2428 {
2429 struct timespec ts;
2430 if (!sock_flag(sk, SOCK_TIMESTAMP))
2431 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2432 ts = ktime_to_timespec(sk->sk_stamp);
2433 if (ts.tv_sec == -1)
2434 return -ENOENT;
2435 if (ts.tv_sec == 0) {
2436 sk->sk_stamp = ktime_get_real();
2437 ts = ktime_to_timespec(sk->sk_stamp);
2438 }
2439 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2440 }
2441 EXPORT_SYMBOL(sock_get_timestampns);
2442
2443 void sock_enable_timestamp(struct sock *sk, int flag)
2444 {
2445 if (!sock_flag(sk, flag)) {
2446 unsigned long previous_flags = sk->sk_flags;
2447
2448 sock_set_flag(sk, flag);
2449 /*
2450 * we just set one of the two flags which require net
2451 * time stamping, but time stamping might have been on
2452 * already because of the other one
2453 */
2454 if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2455 net_enable_timestamp();
2456 }
2457 }
2458
2459 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2460 int level, int type)
2461 {
2462 struct sock_exterr_skb *serr;
2463 struct sk_buff *skb, *skb2;
2464 int copied, err;
2465
2466 err = -EAGAIN;
2467 skb = skb_dequeue(&sk->sk_error_queue);
2468 if (skb == NULL)
2469 goto out;
2470
2471 copied = skb->len;
2472 if (copied > len) {
2473 msg->msg_flags |= MSG_TRUNC;
2474 copied = len;
2475 }
2476 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2477 if (err)
2478 goto out_free_skb;
2479
2480 sock_recv_timestamp(msg, sk, skb);
2481
2482 serr = SKB_EXT_ERR(skb);
2483 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2484
2485 msg->msg_flags |= MSG_ERRQUEUE;
2486 err = copied;
2487
2488 /* Reset and regenerate socket error */
2489 spin_lock_bh(&sk->sk_error_queue.lock);
2490 sk->sk_err = 0;
2491 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2492 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2493 spin_unlock_bh(&sk->sk_error_queue.lock);
2494 sk->sk_error_report(sk);
2495 } else
2496 spin_unlock_bh(&sk->sk_error_queue.lock);
2497
2498 out_free_skb:
2499 kfree_skb(skb);
2500 out:
2501 return err;
2502 }
2503 EXPORT_SYMBOL(sock_recv_errqueue);
2504
2505 /*
2506 * Get a socket option on an socket.
2507 *
2508 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2509 * asynchronous errors should be reported by getsockopt. We assume
2510 * this means if you specify SO_ERROR (otherwise whats the point of it).
2511 */
2512 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2513 char __user *optval, int __user *optlen)
2514 {
2515 struct sock *sk = sock->sk;
2516
2517 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2518 }
2519 EXPORT_SYMBOL(sock_common_getsockopt);
2520
2521 #ifdef CONFIG_COMPAT
2522 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2523 char __user *optval, int __user *optlen)
2524 {
2525 struct sock *sk = sock->sk;
2526
2527 if (sk->sk_prot->compat_getsockopt != NULL)
2528 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2529 optval, optlen);
2530 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2531 }
2532 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2533 #endif
2534
2535 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2536 struct msghdr *msg, size_t size, int flags)
2537 {
2538 struct sock *sk = sock->sk;
2539 int addr_len = 0;
2540 int err;
2541
2542 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2543 flags & ~MSG_DONTWAIT, &addr_len);
2544 if (err >= 0)
2545 msg->msg_namelen = addr_len;
2546 return err;
2547 }
2548 EXPORT_SYMBOL(sock_common_recvmsg);
2549
2550 /*
2551 * Set socket options on an inet socket.
2552 */
2553 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2554 char __user *optval, unsigned int optlen)
2555 {
2556 struct sock *sk = sock->sk;
2557
2558 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2559 }
2560 EXPORT_SYMBOL(sock_common_setsockopt);
2561
2562 #ifdef CONFIG_COMPAT
2563 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2564 char __user *optval, unsigned int optlen)
2565 {
2566 struct sock *sk = sock->sk;
2567
2568 if (sk->sk_prot->compat_setsockopt != NULL)
2569 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2570 optval, optlen);
2571 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2572 }
2573 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2574 #endif
2575
2576 void sk_common_release(struct sock *sk)
2577 {
2578 if (sk->sk_prot->destroy)
2579 sk->sk_prot->destroy(sk);
2580
2581 /*
2582 * Observation: when sock_common_release is called, processes have
2583 * no access to socket. But net still has.
2584 * Step one, detach it from networking:
2585 *
2586 * A. Remove from hash tables.
2587 */
2588
2589 sk->sk_prot->unhash(sk);
2590
2591 /*
2592 * In this point socket cannot receive new packets, but it is possible
2593 * that some packets are in flight because some CPU runs receiver and
2594 * did hash table lookup before we unhashed socket. They will achieve
2595 * receive queue and will be purged by socket destructor.
2596 *
2597 * Also we still have packets pending on receive queue and probably,
2598 * our own packets waiting in device queues. sock_destroy will drain
2599 * receive queue, but transmitted packets will delay socket destruction
2600 * until the last reference will be released.
2601 */
2602
2603 sock_orphan(sk);
2604
2605 xfrm_sk_free_policy(sk);
2606
2607 sk_refcnt_debug_release(sk);
2608
2609 if (sk->sk_frag.page) {
2610 put_page(sk->sk_frag.page);
2611 sk->sk_frag.page = NULL;
2612 }
2613
2614 sock_put(sk);
2615 }
2616 EXPORT_SYMBOL(sk_common_release);
2617
2618 #ifdef CONFIG_PROC_FS
2619 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2620 struct prot_inuse {
2621 int val[PROTO_INUSE_NR];
2622 };
2623
2624 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2625
2626 #ifdef CONFIG_NET_NS
2627 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2628 {
2629 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2630 }
2631 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2632
2633 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2634 {
2635 int cpu, idx = prot->inuse_idx;
2636 int res = 0;
2637
2638 for_each_possible_cpu(cpu)
2639 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2640
2641 return res >= 0 ? res : 0;
2642 }
2643 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2644
2645 static int __net_init sock_inuse_init_net(struct net *net)
2646 {
2647 net->core.inuse = alloc_percpu(struct prot_inuse);
2648 return net->core.inuse ? 0 : -ENOMEM;
2649 }
2650
2651 static void __net_exit sock_inuse_exit_net(struct net *net)
2652 {
2653 free_percpu(net->core.inuse);
2654 }
2655
2656 static struct pernet_operations net_inuse_ops = {
2657 .init = sock_inuse_init_net,
2658 .exit = sock_inuse_exit_net,
2659 };
2660
2661 static __init int net_inuse_init(void)
2662 {
2663 if (register_pernet_subsys(&net_inuse_ops))
2664 panic("Cannot initialize net inuse counters");
2665
2666 return 0;
2667 }
2668
2669 core_initcall(net_inuse_init);
2670 #else
2671 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2672
2673 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2674 {
2675 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2676 }
2677 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2678
2679 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2680 {
2681 int cpu, idx = prot->inuse_idx;
2682 int res = 0;
2683
2684 for_each_possible_cpu(cpu)
2685 res += per_cpu(prot_inuse, cpu).val[idx];
2686
2687 return res >= 0 ? res : 0;
2688 }
2689 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2690 #endif
2691
2692 static void assign_proto_idx(struct proto *prot)
2693 {
2694 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2695
2696 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2697 pr_err("PROTO_INUSE_NR exhausted\n");
2698 return;
2699 }
2700
2701 set_bit(prot->inuse_idx, proto_inuse_idx);
2702 }
2703
2704 static void release_proto_idx(struct proto *prot)
2705 {
2706 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2707 clear_bit(prot->inuse_idx, proto_inuse_idx);
2708 }
2709 #else
2710 static inline void assign_proto_idx(struct proto *prot)
2711 {
2712 }
2713
2714 static inline void release_proto_idx(struct proto *prot)
2715 {
2716 }
2717 #endif
2718
2719 int proto_register(struct proto *prot, int alloc_slab)
2720 {
2721 if (alloc_slab) {
2722 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2723 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2724 NULL);
2725
2726 if (prot->slab == NULL) {
2727 pr_crit("%s: Can't create sock SLAB cache!\n",
2728 prot->name);
2729 goto out;
2730 }
2731
2732 if (prot->rsk_prot != NULL) {
2733 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2734 if (prot->rsk_prot->slab_name == NULL)
2735 goto out_free_sock_slab;
2736
2737 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2738 prot->rsk_prot->obj_size, 0,
2739 SLAB_HWCACHE_ALIGN, NULL);
2740
2741 if (prot->rsk_prot->slab == NULL) {
2742 pr_crit("%s: Can't create request sock SLAB cache!\n",
2743 prot->name);
2744 goto out_free_request_sock_slab_name;
2745 }
2746 }
2747
2748 if (prot->twsk_prot != NULL) {
2749 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2750
2751 if (prot->twsk_prot->twsk_slab_name == NULL)
2752 goto out_free_request_sock_slab;
2753
2754 prot->twsk_prot->twsk_slab =
2755 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2756 prot->twsk_prot->twsk_obj_size,
2757 0,
2758 SLAB_HWCACHE_ALIGN |
2759 prot->slab_flags,
2760 NULL);
2761 if (prot->twsk_prot->twsk_slab == NULL)
2762 goto out_free_timewait_sock_slab_name;
2763 }
2764 }
2765
2766 mutex_lock(&proto_list_mutex);
2767 list_add(&prot->node, &proto_list);
2768 assign_proto_idx(prot);
2769 mutex_unlock(&proto_list_mutex);
2770 return 0;
2771
2772 out_free_timewait_sock_slab_name:
2773 kfree(prot->twsk_prot->twsk_slab_name);
2774 out_free_request_sock_slab:
2775 if (prot->rsk_prot && prot->rsk_prot->slab) {
2776 kmem_cache_destroy(prot->rsk_prot->slab);
2777 prot->rsk_prot->slab = NULL;
2778 }
2779 out_free_request_sock_slab_name:
2780 if (prot->rsk_prot)
2781 kfree(prot->rsk_prot->slab_name);
2782 out_free_sock_slab:
2783 kmem_cache_destroy(prot->slab);
2784 prot->slab = NULL;
2785 out:
2786 return -ENOBUFS;
2787 }
2788 EXPORT_SYMBOL(proto_register);
2789
2790 void proto_unregister(struct proto *prot)
2791 {
2792 mutex_lock(&proto_list_mutex);
2793 release_proto_idx(prot);
2794 list_del(&prot->node);
2795 mutex_unlock(&proto_list_mutex);
2796
2797 if (prot->slab != NULL) {
2798 kmem_cache_destroy(prot->slab);
2799 prot->slab = NULL;
2800 }
2801
2802 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2803 kmem_cache_destroy(prot->rsk_prot->slab);
2804 kfree(prot->rsk_prot->slab_name);
2805 prot->rsk_prot->slab = NULL;
2806 }
2807
2808 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2809 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2810 kfree(prot->twsk_prot->twsk_slab_name);
2811 prot->twsk_prot->twsk_slab = NULL;
2812 }
2813 }
2814 EXPORT_SYMBOL(proto_unregister);
2815
2816 #ifdef CONFIG_PROC_FS
2817 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2818 __acquires(proto_list_mutex)
2819 {
2820 mutex_lock(&proto_list_mutex);
2821 return seq_list_start_head(&proto_list, *pos);
2822 }
2823
2824 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2825 {
2826 return seq_list_next(v, &proto_list, pos);
2827 }
2828
2829 static void proto_seq_stop(struct seq_file *seq, void *v)
2830 __releases(proto_list_mutex)
2831 {
2832 mutex_unlock(&proto_list_mutex);
2833 }
2834
2835 static char proto_method_implemented(const void *method)
2836 {
2837 return method == NULL ? 'n' : 'y';
2838 }
2839 static long sock_prot_memory_allocated(struct proto *proto)
2840 {
2841 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2842 }
2843
2844 static char *sock_prot_memory_pressure(struct proto *proto)
2845 {
2846 return proto->memory_pressure != NULL ?
2847 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2848 }
2849
2850 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2851 {
2852
2853 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2854 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2855 proto->name,
2856 proto->obj_size,
2857 sock_prot_inuse_get(seq_file_net(seq), proto),
2858 sock_prot_memory_allocated(proto),
2859 sock_prot_memory_pressure(proto),
2860 proto->max_header,
2861 proto->slab == NULL ? "no" : "yes",
2862 module_name(proto->owner),
2863 proto_method_implemented(proto->close),
2864 proto_method_implemented(proto->connect),
2865 proto_method_implemented(proto->disconnect),
2866 proto_method_implemented(proto->accept),
2867 proto_method_implemented(proto->ioctl),
2868 proto_method_implemented(proto->init),
2869 proto_method_implemented(proto->destroy),
2870 proto_method_implemented(proto->shutdown),
2871 proto_method_implemented(proto->setsockopt),
2872 proto_method_implemented(proto->getsockopt),
2873 proto_method_implemented(proto->sendmsg),
2874 proto_method_implemented(proto->recvmsg),
2875 proto_method_implemented(proto->sendpage),
2876 proto_method_implemented(proto->bind),
2877 proto_method_implemented(proto->backlog_rcv),
2878 proto_method_implemented(proto->hash),
2879 proto_method_implemented(proto->unhash),
2880 proto_method_implemented(proto->get_port),
2881 proto_method_implemented(proto->enter_memory_pressure));
2882 }
2883
2884 static int proto_seq_show(struct seq_file *seq, void *v)
2885 {
2886 if (v == &proto_list)
2887 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2888 "protocol",
2889 "size",
2890 "sockets",
2891 "memory",
2892 "press",
2893 "maxhdr",
2894 "slab",
2895 "module",
2896 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2897 else
2898 proto_seq_printf(seq, list_entry(v, struct proto, node));
2899 return 0;
2900 }
2901
2902 static const struct seq_operations proto_seq_ops = {
2903 .start = proto_seq_start,
2904 .next = proto_seq_next,
2905 .stop = proto_seq_stop,
2906 .show = proto_seq_show,
2907 };
2908
2909 static int proto_seq_open(struct inode *inode, struct file *file)
2910 {
2911 return seq_open_net(inode, file, &proto_seq_ops,
2912 sizeof(struct seq_net_private));
2913 }
2914
2915 static const struct file_operations proto_seq_fops = {
2916 .owner = THIS_MODULE,
2917 .open = proto_seq_open,
2918 .read = seq_read,
2919 .llseek = seq_lseek,
2920 .release = seq_release_net,
2921 };
2922
2923 static __net_init int proto_init_net(struct net *net)
2924 {
2925 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
2926 return -ENOMEM;
2927
2928 return 0;
2929 }
2930
2931 static __net_exit void proto_exit_net(struct net *net)
2932 {
2933 remove_proc_entry("protocols", net->proc_net);
2934 }
2935
2936
2937 static __net_initdata struct pernet_operations proto_net_ops = {
2938 .init = proto_init_net,
2939 .exit = proto_exit_net,
2940 };
2941
2942 static int __init proto_init(void)
2943 {
2944 return register_pernet_subsys(&proto_net_ops);
2945 }
2946
2947 subsys_initcall(proto_init);
2948
2949 #endif /* PROC_FS */
Linux kernel - Deliverables
This page took 0.0886 seconds and 6 git commands to generate.