projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
net: wrap sock->sk_cgrp_prioidx and ->sk_classid inside a struct
[deliverable/linux.git] / net / core / sock.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
8 *
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 * Alan Cox : Numerous verify_area() problems
17 * Alan Cox : Connecting on a connecting socket
18 * now returns an error for tcp.
19 * Alan Cox : sock->protocol is set correctly.
20 * and is not sometimes left as 0.
21 * Alan Cox : connect handles icmp errors on a
22 * connect properly. Unfortunately there
23 * is a restart syscall nasty there. I
24 * can't match BSD without hacking the C
25 * library. Ideas urgently sought!
26 * Alan Cox : Disallow bind() to addresses that are
27 * not ours - especially broadcast ones!!
28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
30 * instead they leave that for the DESTROY timer.
31 * Alan Cox : Clean up error flag in accept
32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer
33 * was buggy. Put a remove_sock() in the handler
34 * for memory when we hit 0. Also altered the timer
35 * code. The ACK stuff can wait and needs major
36 * TCP layer surgery.
37 * Alan Cox : Fixed TCP ack bug, removed remove sock
38 * and fixed timer/inet_bh race.
39 * Alan Cox : Added zapped flag for TCP
40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 * Rick Sladkey : Relaxed UDP rules for matching packets.
46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
47 * Pauline Middelink : identd support
48 * Alan Cox : Fixed connect() taking signals I think.
49 * Alan Cox : SO_LINGER supported
50 * Alan Cox : Error reporting fixes
51 * Anonymous : inet_create tidied up (sk->reuse setting)
52 * Alan Cox : inet sockets don't set sk->type!
53 * Alan Cox : Split socket option code
54 * Alan Cox : Callbacks
55 * Alan Cox : Nagle flag for Charles & Johannes stuff
56 * Alex : Removed restriction on inet fioctl
57 * Alan Cox : Splitting INET from NET core
58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
60 * Alan Cox : Split IP from generic code
61 * Alan Cox : New kfree_skbmem()
62 * Alan Cox : Make SO_DEBUG superuser only.
63 * Alan Cox : Allow anyone to clear SO_DEBUG
64 * (compatibility fix)
65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
66 * Alan Cox : Allocator for a socket is settable.
67 * Alan Cox : SO_ERROR includes soft errors.
68 * Alan Cox : Allow NULL arguments on some SO_ opts
69 * Alan Cox : Generic socket allocation to make hooks
70 * easier (suggested by Craig Metz).
71 * Michael Pall : SO_ERROR returns positive errno again
72 * Steve Whitehouse: Added default destructor to free
73 * protocol private data.
74 * Steve Whitehouse: Added various other default routines
75 * common to several socket families.
76 * Chris Evans : Call suser() check last on F_SETOWN
77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
79 * Andi Kleen : Fix write_space callback
80 * Chris Evans : Security fixes - signedness again
81 * Arnaldo C. Melo : cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 * This program is free software; you can redistribute it and/or
87 * modify it under the terms of the GNU General Public License
88 * as published by the Free Software Foundation; either version
89 * 2 of the License, or (at your option) any later version.
90 */
91
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/errqueue.h>
97 #include <linux/types.h>
98 #include <linux/socket.h>
99 #include <linux/in.h>
100 #include <linux/kernel.h>
101 #include <linux/module.h>
102 #include <linux/proc_fs.h>
103 #include <linux/seq_file.h>
104 #include <linux/sched.h>
105 #include <linux/timer.h>
106 #include <linux/string.h>
107 #include <linux/sockios.h>
108 #include <linux/net.h>
109 #include <linux/mm.h>
110 #include <linux/slab.h>
111 #include <linux/interrupt.h>
112 #include <linux/poll.h>
113 #include <linux/tcp.h>
114 #include <linux/init.h>
115 #include <linux/highmem.h>
116 #include <linux/user_namespace.h>
117 #include <linux/static_key.h>
118 #include <linux/memcontrol.h>
119 #include <linux/prefetch.h>
120
121 #include <asm/uaccess.h>
122
123 #include <linux/netdevice.h>
124 #include <net/protocol.h>
125 #include <linux/skbuff.h>
126 #include <net/net_namespace.h>
127 #include <net/request_sock.h>
128 #include <net/sock.h>
129 #include <linux/net_tstamp.h>
130 #include <net/xfrm.h>
131 #include <linux/ipsec.h>
132 #include <net/cls_cgroup.h>
133 #include <net/netprio_cgroup.h>
134 #include <linux/sock_diag.h>
135
136 #include <linux/filter.h>
137
138 #include <trace/events/sock.h>
139
140 #ifdef CONFIG_INET
141 #include <net/tcp.h>
142 #endif
143
144 #include <net/busy_poll.h>
145
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148
149 /**
150 * sk_ns_capable - General socket capability test
151 * @sk: Socket to use a capability on or through
152 * @user_ns: The user namespace of the capability to use
153 * @cap: The capability to use
154 *
155 * Test to see if the opener of the socket had when the socket was
156 * created and the current process has the capability @cap in the user
157 * namespace @user_ns.
158 */
159 bool sk_ns_capable(const struct sock *sk,
160 struct user_namespace *user_ns, int cap)
161 {
162 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
163 ns_capable(user_ns, cap);
164 }
165 EXPORT_SYMBOL(sk_ns_capable);
166
167 /**
168 * sk_capable - Socket global capability test
169 * @sk: Socket to use a capability on or through
170 * @cap: The global capability to use
171 *
172 * Test to see if the opener of the socket had when the socket was
173 * created and the current process has the capability @cap in all user
174 * namespaces.
175 */
176 bool sk_capable(const struct sock *sk, int cap)
177 {
178 return sk_ns_capable(sk, &init_user_ns, cap);
179 }
180 EXPORT_SYMBOL(sk_capable);
181
182 /**
183 * sk_net_capable - Network namespace socket capability test
184 * @sk: Socket to use a capability on or through
185 * @cap: The capability to use
186 *
187 * Test to see if the opener of the socket had when the socket was created
188 * and the current process has the capability @cap over the network namespace
189 * the socket is a member of.
190 */
191 bool sk_net_capable(const struct sock *sk, int cap)
192 {
193 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
194 }
195 EXPORT_SYMBOL(sk_net_capable);
196
197
198 #ifdef CONFIG_MEMCG_KMEM
199 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
200 {
201 struct proto *proto;
202 int ret = 0;
203
204 mutex_lock(&proto_list_mutex);
205 list_for_each_entry(proto, &proto_list, node) {
206 if (proto->init_cgroup) {
207 ret = proto->init_cgroup(memcg, ss);
208 if (ret)
209 goto out;
210 }
211 }
212
213 mutex_unlock(&proto_list_mutex);
214 return ret;
215 out:
216 list_for_each_entry_continue_reverse(proto, &proto_list, node)
217 if (proto->destroy_cgroup)
218 proto->destroy_cgroup(memcg);
219 mutex_unlock(&proto_list_mutex);
220 return ret;
221 }
222
223 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
224 {
225 struct proto *proto;
226
227 mutex_lock(&proto_list_mutex);
228 list_for_each_entry_reverse(proto, &proto_list, node)
229 if (proto->destroy_cgroup)
230 proto->destroy_cgroup(memcg);
231 mutex_unlock(&proto_list_mutex);
232 }
233 #endif
234
235 /*
236 * Each address family might have different locking rules, so we have
237 * one slock key per address family:
238 */
239 static struct lock_class_key af_family_keys[AF_MAX];
240 static struct lock_class_key af_family_slock_keys[AF_MAX];
241
242 #if defined(CONFIG_MEMCG_KMEM)
243 struct static_key memcg_socket_limit_enabled;
244 EXPORT_SYMBOL(memcg_socket_limit_enabled);
245 #endif
246
247 /*
248 * Make lock validator output more readable. (we pre-construct these
249 * strings build-time, so that runtime initialization of socket
250 * locks is fast):
251 */
252 static const char *const af_family_key_strings[AF_MAX+1] = {
253 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
254 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
255 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
256 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
257 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
258 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
259 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
260 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
261 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
262 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
263 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
264 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
265 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
266 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
267 };
268 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
269 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
270 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
271 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
272 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
273 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
274 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
275 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
276 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
277 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
278 "slock-27" , "slock-28" , "slock-AF_CAN" ,
279 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
280 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
281 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
282 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
283 };
284 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
285 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
286 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
287 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
288 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
289 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
290 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
291 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
292 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
293 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
294 "clock-27" , "clock-28" , "clock-AF_CAN" ,
295 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
296 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
297 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
298 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
299 };
300
301 /*
302 * sk_callback_lock locking rules are per-address-family,
303 * so split the lock classes by using a per-AF key:
304 */
305 static struct lock_class_key af_callback_keys[AF_MAX];
306
307 /* Take into consideration the size of the struct sk_buff overhead in the
308 * determination of these values, since that is non-constant across
309 * platforms. This makes socket queueing behavior and performance
310 * not depend upon such differences.
311 */
312 #define _SK_MEM_PACKETS 256
313 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
314 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
315 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
316
317 /* Run time adjustable parameters. */
318 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
319 EXPORT_SYMBOL(sysctl_wmem_max);
320 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
321 EXPORT_SYMBOL(sysctl_rmem_max);
322 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
323 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
324
325 /* Maximal space eaten by iovec or ancillary data plus some space */
326 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
327 EXPORT_SYMBOL(sysctl_optmem_max);
328
329 int sysctl_tstamp_allow_data __read_mostly = 1;
330
331 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
332 EXPORT_SYMBOL_GPL(memalloc_socks);
333
334 /**
335 * sk_set_memalloc - sets %SOCK_MEMALLOC
336 * @sk: socket to set it on
337 *
338 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
339 * It's the responsibility of the admin to adjust min_free_kbytes
340 * to meet the requirements
341 */
342 void sk_set_memalloc(struct sock *sk)
343 {
344 sock_set_flag(sk, SOCK_MEMALLOC);
345 sk->sk_allocation |= __GFP_MEMALLOC;
346 static_key_slow_inc(&memalloc_socks);
347 }
348 EXPORT_SYMBOL_GPL(sk_set_memalloc);
349
350 void sk_clear_memalloc(struct sock *sk)
351 {
352 sock_reset_flag(sk, SOCK_MEMALLOC);
353 sk->sk_allocation &= ~__GFP_MEMALLOC;
354 static_key_slow_dec(&memalloc_socks);
355
356 /*
357 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
358 * progress of swapping. SOCK_MEMALLOC may be cleared while
359 * it has rmem allocations due to the last swapfile being deactivated
360 * but there is a risk that the socket is unusable due to exceeding
361 * the rmem limits. Reclaim the reserves and obey rmem limits again.
362 */
363 sk_mem_reclaim(sk);
364 }
365 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
366
367 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
368 {
369 int ret;
370 unsigned long pflags = current->flags;
371
372 /* these should have been dropped before queueing */
373 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
374
375 current->flags |= PF_MEMALLOC;
376 ret = sk->sk_backlog_rcv(sk, skb);
377 tsk_restore_flags(current, pflags, PF_MEMALLOC);
378
379 return ret;
380 }
381 EXPORT_SYMBOL(__sk_backlog_rcv);
382
383 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
384 {
385 struct timeval tv;
386
387 if (optlen < sizeof(tv))
388 return -EINVAL;
389 if (copy_from_user(&tv, optval, sizeof(tv)))
390 return -EFAULT;
391 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
392 return -EDOM;
393
394 if (tv.tv_sec < 0) {
395 static int warned __read_mostly;
396
397 *timeo_p = 0;
398 if (warned < 10 && net_ratelimit()) {
399 warned++;
400 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
401 __func__, current->comm, task_pid_nr(current));
402 }
403 return 0;
404 }
405 *timeo_p = MAX_SCHEDULE_TIMEOUT;
406 if (tv.tv_sec == 0 && tv.tv_usec == 0)
407 return 0;
408 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
409 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
410 return 0;
411 }
412
413 static void sock_warn_obsolete_bsdism(const char *name)
414 {
415 static int warned;
416 static char warncomm[TASK_COMM_LEN];
417 if (strcmp(warncomm, current->comm) && warned < 5) {
418 strcpy(warncomm, current->comm);
419 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
420 warncomm, name);
421 warned++;
422 }
423 }
424
425 static bool sock_needs_netstamp(const struct sock *sk)
426 {
427 switch (sk->sk_family) {
428 case AF_UNSPEC:
429 case AF_UNIX:
430 return false;
431 default:
432 return true;
433 }
434 }
435
436 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
437
438 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
439 {
440 if (sk->sk_flags & flags) {
441 sk->sk_flags &= ~flags;
442 if (sock_needs_netstamp(sk) &&
443 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
444 net_disable_timestamp();
445 }
446 }
447
448
449 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
450 {
451 int err;
452 unsigned long flags;
453 struct sk_buff_head *list = &sk->sk_receive_queue;
454
455 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
456 atomic_inc(&sk->sk_drops);
457 trace_sock_rcvqueue_full(sk, skb);
458 return -ENOMEM;
459 }
460
461 err = sk_filter(sk, skb);
462 if (err)
463 return err;
464
465 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
466 atomic_inc(&sk->sk_drops);
467 return -ENOBUFS;
468 }
469
470 skb->dev = NULL;
471 skb_set_owner_r(skb, sk);
472
473 /* we escape from rcu protected region, make sure we dont leak
474 * a norefcounted dst
475 */
476 skb_dst_force(skb);
477
478 spin_lock_irqsave(&list->lock, flags);
479 sock_skb_set_dropcount(sk, skb);
480 __skb_queue_tail(list, skb);
481 spin_unlock_irqrestore(&list->lock, flags);
482
483 if (!sock_flag(sk, SOCK_DEAD))
484 sk->sk_data_ready(sk);
485 return 0;
486 }
487 EXPORT_SYMBOL(sock_queue_rcv_skb);
488
489 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
490 {
491 int rc = NET_RX_SUCCESS;
492
493 if (sk_filter(sk, skb))
494 goto discard_and_relse;
495
496 skb->dev = NULL;
497
498 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
499 atomic_inc(&sk->sk_drops);
500 goto discard_and_relse;
501 }
502 if (nested)
503 bh_lock_sock_nested(sk);
504 else
505 bh_lock_sock(sk);
506 if (!sock_owned_by_user(sk)) {
507 /*
508 * trylock + unlock semantics:
509 */
510 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
511
512 rc = sk_backlog_rcv(sk, skb);
513
514 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
515 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
516 bh_unlock_sock(sk);
517 atomic_inc(&sk->sk_drops);
518 goto discard_and_relse;
519 }
520
521 bh_unlock_sock(sk);
522 out:
523 sock_put(sk);
524 return rc;
525 discard_and_relse:
526 kfree_skb(skb);
527 goto out;
528 }
529 EXPORT_SYMBOL(sk_receive_skb);
530
531 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
532 {
533 struct dst_entry *dst = __sk_dst_get(sk);
534
535 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
536 sk_tx_queue_clear(sk);
537 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
538 dst_release(dst);
539 return NULL;
540 }
541
542 return dst;
543 }
544 EXPORT_SYMBOL(__sk_dst_check);
545
546 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
547 {
548 struct dst_entry *dst = sk_dst_get(sk);
549
550 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
551 sk_dst_reset(sk);
552 dst_release(dst);
553 return NULL;
554 }
555
556 return dst;
557 }
558 EXPORT_SYMBOL(sk_dst_check);
559
560 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
561 int optlen)
562 {
563 int ret = -ENOPROTOOPT;
564 #ifdef CONFIG_NETDEVICES
565 struct net *net = sock_net(sk);
566 char devname[IFNAMSIZ];
567 int index;
568
569 /* Sorry... */
570 ret = -EPERM;
571 if (!ns_capable(net->user_ns, CAP_NET_RAW))
572 goto out;
573
574 ret = -EINVAL;
575 if (optlen < 0)
576 goto out;
577
578 /* Bind this socket to a particular device like "eth0",
579 * as specified in the passed interface name. If the
580 * name is "" or the option length is zero the socket
581 * is not bound.
582 */
583 if (optlen > IFNAMSIZ - 1)
584 optlen = IFNAMSIZ - 1;
585 memset(devname, 0, sizeof(devname));
586
587 ret = -EFAULT;
588 if (copy_from_user(devname, optval, optlen))
589 goto out;
590
591 index = 0;
592 if (devname[0] != '\0') {
593 struct net_device *dev;
594
595 rcu_read_lock();
596 dev = dev_get_by_name_rcu(net, devname);
597 if (dev)
598 index = dev->ifindex;
599 rcu_read_unlock();
600 ret = -ENODEV;
601 if (!dev)
602 goto out;
603 }
604
605 lock_sock(sk);
606 sk->sk_bound_dev_if = index;
607 sk_dst_reset(sk);
608 release_sock(sk);
609
610 ret = 0;
611
612 out:
613 #endif
614
615 return ret;
616 }
617
618 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
619 int __user *optlen, int len)
620 {
621 int ret = -ENOPROTOOPT;
622 #ifdef CONFIG_NETDEVICES
623 struct net *net = sock_net(sk);
624 char devname[IFNAMSIZ];
625
626 if (sk->sk_bound_dev_if == 0) {
627 len = 0;
628 goto zero;
629 }
630
631 ret = -EINVAL;
632 if (len < IFNAMSIZ)
633 goto out;
634
635 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
636 if (ret)
637 goto out;
638
639 len = strlen(devname) + 1;
640
641 ret = -EFAULT;
642 if (copy_to_user(optval, devname, len))
643 goto out;
644
645 zero:
646 ret = -EFAULT;
647 if (put_user(len, optlen))
648 goto out;
649
650 ret = 0;
651
652 out:
653 #endif
654
655 return ret;
656 }
657
658 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
659 {
660 if (valbool)
661 sock_set_flag(sk, bit);
662 else
663 sock_reset_flag(sk, bit);
664 }
665
666 bool sk_mc_loop(struct sock *sk)
667 {
668 if (dev_recursion_level())
669 return false;
670 if (!sk)
671 return true;
672 switch (sk->sk_family) {
673 case AF_INET:
674 return inet_sk(sk)->mc_loop;
675 #if IS_ENABLED(CONFIG_IPV6)
676 case AF_INET6:
677 return inet6_sk(sk)->mc_loop;
678 #endif
679 }
680 WARN_ON(1);
681 return true;
682 }
683 EXPORT_SYMBOL(sk_mc_loop);
684
685 /*
686 * This is meant for all protocols to use and covers goings on
687 * at the socket level. Everything here is generic.
688 */
689
690 int sock_setsockopt(struct socket *sock, int level, int optname,
691 char __user *optval, unsigned int optlen)
692 {
693 struct sock *sk = sock->sk;
694 int val;
695 int valbool;
696 struct linger ling;
697 int ret = 0;
698
699 /*
700 * Options without arguments
701 */
702
703 if (optname == SO_BINDTODEVICE)
704 return sock_setbindtodevice(sk, optval, optlen);
705
706 if (optlen < sizeof(int))
707 return -EINVAL;
708
709 if (get_user(val, (int __user *)optval))
710 return -EFAULT;
711
712 valbool = val ? 1 : 0;
713
714 lock_sock(sk);
715
716 switch (optname) {
717 case SO_DEBUG:
718 if (val && !capable(CAP_NET_ADMIN))
719 ret = -EACCES;
720 else
721 sock_valbool_flag(sk, SOCK_DBG, valbool);
722 break;
723 case SO_REUSEADDR:
724 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
725 break;
726 case SO_REUSEPORT:
727 sk->sk_reuseport = valbool;
728 break;
729 case SO_TYPE:
730 case SO_PROTOCOL:
731 case SO_DOMAIN:
732 case SO_ERROR:
733 ret = -ENOPROTOOPT;
734 break;
735 case SO_DONTROUTE:
736 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
737 break;
738 case SO_BROADCAST:
739 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
740 break;
741 case SO_SNDBUF:
742 /* Don't error on this BSD doesn't and if you think
743 * about it this is right. Otherwise apps have to
744 * play 'guess the biggest size' games. RCVBUF/SNDBUF
745 * are treated in BSD as hints
746 */
747 val = min_t(u32, val, sysctl_wmem_max);
748 set_sndbuf:
749 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
750 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
751 /* Wake up sending tasks if we upped the value. */
752 sk->sk_write_space(sk);
753 break;
754
755 case SO_SNDBUFFORCE:
756 if (!capable(CAP_NET_ADMIN)) {
757 ret = -EPERM;
758 break;
759 }
760 goto set_sndbuf;
761
762 case SO_RCVBUF:
763 /* Don't error on this BSD doesn't and if you think
764 * about it this is right. Otherwise apps have to
765 * play 'guess the biggest size' games. RCVBUF/SNDBUF
766 * are treated in BSD as hints
767 */
768 val = min_t(u32, val, sysctl_rmem_max);
769 set_rcvbuf:
770 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
771 /*
772 * We double it on the way in to account for
773 * "struct sk_buff" etc. overhead. Applications
774 * assume that the SO_RCVBUF setting they make will
775 * allow that much actual data to be received on that
776 * socket.
777 *
778 * Applications are unaware that "struct sk_buff" and
779 * other overheads allocate from the receive buffer
780 * during socket buffer allocation.
781 *
782 * And after considering the possible alternatives,
783 * returning the value we actually used in getsockopt
784 * is the most desirable behavior.
785 */
786 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
787 break;
788
789 case SO_RCVBUFFORCE:
790 if (!capable(CAP_NET_ADMIN)) {
791 ret = -EPERM;
792 break;
793 }
794 goto set_rcvbuf;
795
796 case SO_KEEPALIVE:
797 #ifdef CONFIG_INET
798 if (sk->sk_protocol == IPPROTO_TCP &&
799 sk->sk_type == SOCK_STREAM)
800 tcp_set_keepalive(sk, valbool);
801 #endif
802 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
803 break;
804
805 case SO_OOBINLINE:
806 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
807 break;
808
809 case SO_NO_CHECK:
810 sk->sk_no_check_tx = valbool;
811 break;
812
813 case SO_PRIORITY:
814 if ((val >= 0 && val <= 6) ||
815 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
816 sk->sk_priority = val;
817 else
818 ret = -EPERM;
819 break;
820
821 case SO_LINGER:
822 if (optlen < sizeof(ling)) {
823 ret = -EINVAL; /* 1003.1g */
824 break;
825 }
826 if (copy_from_user(&ling, optval, sizeof(ling))) {
827 ret = -EFAULT;
828 break;
829 }
830 if (!ling.l_onoff)
831 sock_reset_flag(sk, SOCK_LINGER);
832 else {
833 #if (BITS_PER_LONG == 32)
834 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
835 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
836 else
837 #endif
838 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
839 sock_set_flag(sk, SOCK_LINGER);
840 }
841 break;
842
843 case SO_BSDCOMPAT:
844 sock_warn_obsolete_bsdism("setsockopt");
845 break;
846
847 case SO_PASSCRED:
848 if (valbool)
849 set_bit(SOCK_PASSCRED, &sock->flags);
850 else
851 clear_bit(SOCK_PASSCRED, &sock->flags);
852 break;
853
854 case SO_TIMESTAMP:
855 case SO_TIMESTAMPNS:
856 if (valbool) {
857 if (optname == SO_TIMESTAMP)
858 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
859 else
860 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
861 sock_set_flag(sk, SOCK_RCVTSTAMP);
862 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
863 } else {
864 sock_reset_flag(sk, SOCK_RCVTSTAMP);
865 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
866 }
867 break;
868
869 case SO_TIMESTAMPING:
870 if (val & ~SOF_TIMESTAMPING_MASK) {
871 ret = -EINVAL;
872 break;
873 }
874
875 if (val & SOF_TIMESTAMPING_OPT_ID &&
876 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
877 if (sk->sk_protocol == IPPROTO_TCP) {
878 if (sk->sk_state != TCP_ESTABLISHED) {
879 ret = -EINVAL;
880 break;
881 }
882 sk->sk_tskey = tcp_sk(sk)->snd_una;
883 } else {
884 sk->sk_tskey = 0;
885 }
886 }
887 sk->sk_tsflags = val;
888 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
889 sock_enable_timestamp(sk,
890 SOCK_TIMESTAMPING_RX_SOFTWARE);
891 else
892 sock_disable_timestamp(sk,
893 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
894 break;
895
896 case SO_RCVLOWAT:
897 if (val < 0)
898 val = INT_MAX;
899 sk->sk_rcvlowat = val ? : 1;
900 break;
901
902 case SO_RCVTIMEO:
903 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
904 break;
905
906 case SO_SNDTIMEO:
907 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
908 break;
909
910 case SO_ATTACH_FILTER:
911 ret = -EINVAL;
912 if (optlen == sizeof(struct sock_fprog)) {
913 struct sock_fprog fprog;
914
915 ret = -EFAULT;
916 if (copy_from_user(&fprog, optval, sizeof(fprog)))
917 break;
918
919 ret = sk_attach_filter(&fprog, sk);
920 }
921 break;
922
923 case SO_ATTACH_BPF:
924 ret = -EINVAL;
925 if (optlen == sizeof(u32)) {
926 u32 ufd;
927
928 ret = -EFAULT;
929 if (copy_from_user(&ufd, optval, sizeof(ufd)))
930 break;
931
932 ret = sk_attach_bpf(ufd, sk);
933 }
934 break;
935
936 case SO_DETACH_FILTER:
937 ret = sk_detach_filter(sk);
938 break;
939
940 case SO_LOCK_FILTER:
941 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
942 ret = -EPERM;
943 else
944 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
945 break;
946
947 case SO_PASSSEC:
948 if (valbool)
949 set_bit(SOCK_PASSSEC, &sock->flags);
950 else
951 clear_bit(SOCK_PASSSEC, &sock->flags);
952 break;
953 case SO_MARK:
954 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
955 ret = -EPERM;
956 else
957 sk->sk_mark = val;
958 break;
959
960 case SO_RXQ_OVFL:
961 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
962 break;
963
964 case SO_WIFI_STATUS:
965 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
966 break;
967
968 case SO_PEEK_OFF:
969 if (sock->ops->set_peek_off)
970 ret = sock->ops->set_peek_off(sk, val);
971 else
972 ret = -EOPNOTSUPP;
973 break;
974
975 case SO_NOFCS:
976 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
977 break;
978
979 case SO_SELECT_ERR_QUEUE:
980 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
981 break;
982
983 #ifdef CONFIG_NET_RX_BUSY_POLL
984 case SO_BUSY_POLL:
985 /* allow unprivileged users to decrease the value */
986 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
987 ret = -EPERM;
988 else {
989 if (val < 0)
990 ret = -EINVAL;
991 else
992 sk->sk_ll_usec = val;
993 }
994 break;
995 #endif
996
997 case SO_MAX_PACING_RATE:
998 sk->sk_max_pacing_rate = val;
999 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1000 sk->sk_max_pacing_rate);
1001 break;
1002
1003 case SO_INCOMING_CPU:
1004 sk->sk_incoming_cpu = val;
1005 break;
1006
1007 default:
1008 ret = -ENOPROTOOPT;
1009 break;
1010 }
1011 release_sock(sk);
1012 return ret;
1013 }
1014 EXPORT_SYMBOL(sock_setsockopt);
1015
1016
1017 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1018 struct ucred *ucred)
1019 {
1020 ucred->pid = pid_vnr(pid);
1021 ucred->uid = ucred->gid = -1;
1022 if (cred) {
1023 struct user_namespace *current_ns = current_user_ns();
1024
1025 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1026 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1027 }
1028 }
1029
1030 int sock_getsockopt(struct socket *sock, int level, int optname,
1031 char __user *optval, int __user *optlen)
1032 {
1033 struct sock *sk = sock->sk;
1034
1035 union {
1036 int val;
1037 struct linger ling;
1038 struct timeval tm;
1039 } v;
1040
1041 int lv = sizeof(int);
1042 int len;
1043
1044 if (get_user(len, optlen))
1045 return -EFAULT;
1046 if (len < 0)
1047 return -EINVAL;
1048
1049 memset(&v, 0, sizeof(v));
1050
1051 switch (optname) {
1052 case SO_DEBUG:
1053 v.val = sock_flag(sk, SOCK_DBG);
1054 break;
1055
1056 case SO_DONTROUTE:
1057 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1058 break;
1059
1060 case SO_BROADCAST:
1061 v.val = sock_flag(sk, SOCK_BROADCAST);
1062 break;
1063
1064 case SO_SNDBUF:
1065 v.val = sk->sk_sndbuf;
1066 break;
1067
1068 case SO_RCVBUF:
1069 v.val = sk->sk_rcvbuf;
1070 break;
1071
1072 case SO_REUSEADDR:
1073 v.val = sk->sk_reuse;
1074 break;
1075
1076 case SO_REUSEPORT:
1077 v.val = sk->sk_reuseport;
1078 break;
1079
1080 case SO_KEEPALIVE:
1081 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1082 break;
1083
1084 case SO_TYPE:
1085 v.val = sk->sk_type;
1086 break;
1087
1088 case SO_PROTOCOL:
1089 v.val = sk->sk_protocol;
1090 break;
1091
1092 case SO_DOMAIN:
1093 v.val = sk->sk_family;
1094 break;
1095
1096 case SO_ERROR:
1097 v.val = -sock_error(sk);
1098 if (v.val == 0)
1099 v.val = xchg(&sk->sk_err_soft, 0);
1100 break;
1101
1102 case SO_OOBINLINE:
1103 v.val = sock_flag(sk, SOCK_URGINLINE);
1104 break;
1105
1106 case SO_NO_CHECK:
1107 v.val = sk->sk_no_check_tx;
1108 break;
1109
1110 case SO_PRIORITY:
1111 v.val = sk->sk_priority;
1112 break;
1113
1114 case SO_LINGER:
1115 lv = sizeof(v.ling);
1116 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1117 v.ling.l_linger = sk->sk_lingertime / HZ;
1118 break;
1119
1120 case SO_BSDCOMPAT:
1121 sock_warn_obsolete_bsdism("getsockopt");
1122 break;
1123
1124 case SO_TIMESTAMP:
1125 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1126 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1127 break;
1128
1129 case SO_TIMESTAMPNS:
1130 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1131 break;
1132
1133 case SO_TIMESTAMPING:
1134 v.val = sk->sk_tsflags;
1135 break;
1136
1137 case SO_RCVTIMEO:
1138 lv = sizeof(struct timeval);
1139 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1140 v.tm.tv_sec = 0;
1141 v.tm.tv_usec = 0;
1142 } else {
1143 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1144 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1145 }
1146 break;
1147
1148 case SO_SNDTIMEO:
1149 lv = sizeof(struct timeval);
1150 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1151 v.tm.tv_sec = 0;
1152 v.tm.tv_usec = 0;
1153 } else {
1154 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1155 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1156 }
1157 break;
1158
1159 case SO_RCVLOWAT:
1160 v.val = sk->sk_rcvlowat;
1161 break;
1162
1163 case SO_SNDLOWAT:
1164 v.val = 1;
1165 break;
1166
1167 case SO_PASSCRED:
1168 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1169 break;
1170
1171 case SO_PEERCRED:
1172 {
1173 struct ucred peercred;
1174 if (len > sizeof(peercred))
1175 len = sizeof(peercred);
1176 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1177 if (copy_to_user(optval, &peercred, len))
1178 return -EFAULT;
1179 goto lenout;
1180 }
1181
1182 case SO_PEERNAME:
1183 {
1184 char address[128];
1185
1186 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1187 return -ENOTCONN;
1188 if (lv < len)
1189 return -EINVAL;
1190 if (copy_to_user(optval, address, len))
1191 return -EFAULT;
1192 goto lenout;
1193 }
1194
1195 /* Dubious BSD thing... Probably nobody even uses it, but
1196 * the UNIX standard wants it for whatever reason... -DaveM
1197 */
1198 case SO_ACCEPTCONN:
1199 v.val = sk->sk_state == TCP_LISTEN;
1200 break;
1201
1202 case SO_PASSSEC:
1203 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1204 break;
1205
1206 case SO_PEERSEC:
1207 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1208
1209 case SO_MARK:
1210 v.val = sk->sk_mark;
1211 break;
1212
1213 case SO_RXQ_OVFL:
1214 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1215 break;
1216
1217 case SO_WIFI_STATUS:
1218 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1219 break;
1220
1221 case SO_PEEK_OFF:
1222 if (!sock->ops->set_peek_off)
1223 return -EOPNOTSUPP;
1224
1225 v.val = sk->sk_peek_off;
1226 break;
1227 case SO_NOFCS:
1228 v.val = sock_flag(sk, SOCK_NOFCS);
1229 break;
1230
1231 case SO_BINDTODEVICE:
1232 return sock_getbindtodevice(sk, optval, optlen, len);
1233
1234 case SO_GET_FILTER:
1235 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1236 if (len < 0)
1237 return len;
1238
1239 goto lenout;
1240
1241 case SO_LOCK_FILTER:
1242 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1243 break;
1244
1245 case SO_BPF_EXTENSIONS:
1246 v.val = bpf_tell_extensions();
1247 break;
1248
1249 case SO_SELECT_ERR_QUEUE:
1250 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1251 break;
1252
1253 #ifdef CONFIG_NET_RX_BUSY_POLL
1254 case SO_BUSY_POLL:
1255 v.val = sk->sk_ll_usec;
1256 break;
1257 #endif
1258
1259 case SO_MAX_PACING_RATE:
1260 v.val = sk->sk_max_pacing_rate;
1261 break;
1262
1263 case SO_INCOMING_CPU:
1264 v.val = sk->sk_incoming_cpu;
1265 break;
1266
1267 default:
1268 /* We implement the SO_SNDLOWAT etc to not be settable
1269 * (1003.1g 7).
1270 */
1271 return -ENOPROTOOPT;
1272 }
1273
1274 if (len > lv)
1275 len = lv;
1276 if (copy_to_user(optval, &v, len))
1277 return -EFAULT;
1278 lenout:
1279 if (put_user(len, optlen))
1280 return -EFAULT;
1281 return 0;
1282 }
1283
1284 /*
1285 * Initialize an sk_lock.
1286 *
1287 * (We also register the sk_lock with the lock validator.)
1288 */
1289 static inline void sock_lock_init(struct sock *sk)
1290 {
1291 sock_lock_init_class_and_name(sk,
1292 af_family_slock_key_strings[sk->sk_family],
1293 af_family_slock_keys + sk->sk_family,
1294 af_family_key_strings[sk->sk_family],
1295 af_family_keys + sk->sk_family);
1296 }
1297
1298 /*
1299 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1300 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1301 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1302 */
1303 static void sock_copy(struct sock *nsk, const struct sock *osk)
1304 {
1305 #ifdef CONFIG_SECURITY_NETWORK
1306 void *sptr = nsk->sk_security;
1307 #endif
1308 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1309
1310 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1311 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1312
1313 #ifdef CONFIG_SECURITY_NETWORK
1314 nsk->sk_security = sptr;
1315 security_sk_clone(osk, nsk);
1316 #endif
1317 }
1318
1319 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1320 {
1321 unsigned long nulls1, nulls2;
1322
1323 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1324 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1325 if (nulls1 > nulls2)
1326 swap(nulls1, nulls2);
1327
1328 if (nulls1 != 0)
1329 memset((char *)sk, 0, nulls1);
1330 memset((char *)sk + nulls1 + sizeof(void *), 0,
1331 nulls2 - nulls1 - sizeof(void *));
1332 memset((char *)sk + nulls2 + sizeof(void *), 0,
1333 size - nulls2 - sizeof(void *));
1334 }
1335 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1336
1337 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1338 int family)
1339 {
1340 struct sock *sk;
1341 struct kmem_cache *slab;
1342
1343 slab = prot->slab;
1344 if (slab != NULL) {
1345 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1346 if (!sk)
1347 return sk;
1348 if (priority & __GFP_ZERO) {
1349 if (prot->clear_sk)
1350 prot->clear_sk(sk, prot->obj_size);
1351 else
1352 sk_prot_clear_nulls(sk, prot->obj_size);
1353 }
1354 } else
1355 sk = kmalloc(prot->obj_size, priority);
1356
1357 if (sk != NULL) {
1358 kmemcheck_annotate_bitfield(sk, flags);
1359
1360 if (security_sk_alloc(sk, family, priority))
1361 goto out_free;
1362
1363 if (!try_module_get(prot->owner))
1364 goto out_free_sec;
1365 sk_tx_queue_clear(sk);
1366 }
1367
1368 return sk;
1369
1370 out_free_sec:
1371 security_sk_free(sk);
1372 out_free:
1373 if (slab != NULL)
1374 kmem_cache_free(slab, sk);
1375 else
1376 kfree(sk);
1377 return NULL;
1378 }
1379
1380 static void sk_prot_free(struct proto *prot, struct sock *sk)
1381 {
1382 struct kmem_cache *slab;
1383 struct module *owner;
1384
1385 owner = prot->owner;
1386 slab = prot->slab;
1387
1388 security_sk_free(sk);
1389 if (slab != NULL)
1390 kmem_cache_free(slab, sk);
1391 else
1392 kfree(sk);
1393 module_put(owner);
1394 }
1395
1396 /**
1397 * sk_alloc - All socket objects are allocated here
1398 * @net: the applicable net namespace
1399 * @family: protocol family
1400 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1401 * @prot: struct proto associated with this new sock instance
1402 * @kern: is this to be a kernel socket?
1403 */
1404 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1405 struct proto *prot, int kern)
1406 {
1407 struct sock *sk;
1408
1409 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1410 if (sk) {
1411 sk->sk_family = family;
1412 /*
1413 * See comment in struct sock definition to understand
1414 * why we need sk_prot_creator -acme
1415 */
1416 sk->sk_prot = sk->sk_prot_creator = prot;
1417 sock_lock_init(sk);
1418 sk->sk_net_refcnt = kern ? 0 : 1;
1419 if (likely(sk->sk_net_refcnt))
1420 get_net(net);
1421 sock_net_set(sk, net);
1422 atomic_set(&sk->sk_wmem_alloc, 1);
1423
1424 sock_update_classid(&sk->sk_cgrp_data);
1425 sock_update_netprioidx(&sk->sk_cgrp_data);
1426 }
1427
1428 return sk;
1429 }
1430 EXPORT_SYMBOL(sk_alloc);
1431
1432 void sk_destruct(struct sock *sk)
1433 {
1434 struct sk_filter *filter;
1435
1436 if (sk->sk_destruct)
1437 sk->sk_destruct(sk);
1438
1439 filter = rcu_dereference_check(sk->sk_filter,
1440 atomic_read(&sk->sk_wmem_alloc) == 0);
1441 if (filter) {
1442 sk_filter_uncharge(sk, filter);
1443 RCU_INIT_POINTER(sk->sk_filter, NULL);
1444 }
1445
1446 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1447
1448 if (atomic_read(&sk->sk_omem_alloc))
1449 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1450 __func__, atomic_read(&sk->sk_omem_alloc));
1451
1452 if (sk->sk_peer_cred)
1453 put_cred(sk->sk_peer_cred);
1454 put_pid(sk->sk_peer_pid);
1455 if (likely(sk->sk_net_refcnt))
1456 put_net(sock_net(sk));
1457 sk_prot_free(sk->sk_prot_creator, sk);
1458 }
1459
1460 static void __sk_free(struct sock *sk)
1461 {
1462 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1463 sock_diag_broadcast_destroy(sk);
1464 else
1465 sk_destruct(sk);
1466 }
1467
1468 void sk_free(struct sock *sk)
1469 {
1470 /*
1471 * We subtract one from sk_wmem_alloc and can know if
1472 * some packets are still in some tx queue.
1473 * If not null, sock_wfree() will call __sk_free(sk) later
1474 */
1475 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1476 __sk_free(sk);
1477 }
1478 EXPORT_SYMBOL(sk_free);
1479
1480 static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1481 {
1482 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1483 sock_update_memcg(newsk);
1484 }
1485
1486 /**
1487 * sk_clone_lock - clone a socket, and lock its clone
1488 * @sk: the socket to clone
1489 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1490 *
1491 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1492 */
1493 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1494 {
1495 struct sock *newsk;
1496 bool is_charged = true;
1497
1498 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1499 if (newsk != NULL) {
1500 struct sk_filter *filter;
1501
1502 sock_copy(newsk, sk);
1503
1504 /* SANITY */
1505 if (likely(newsk->sk_net_refcnt))
1506 get_net(sock_net(newsk));
1507 sk_node_init(&newsk->sk_node);
1508 sock_lock_init(newsk);
1509 bh_lock_sock(newsk);
1510 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1511 newsk->sk_backlog.len = 0;
1512
1513 atomic_set(&newsk->sk_rmem_alloc, 0);
1514 /*
1515 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1516 */
1517 atomic_set(&newsk->sk_wmem_alloc, 1);
1518 atomic_set(&newsk->sk_omem_alloc, 0);
1519 skb_queue_head_init(&newsk->sk_receive_queue);
1520 skb_queue_head_init(&newsk->sk_write_queue);
1521
1522 rwlock_init(&newsk->sk_callback_lock);
1523 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1524 af_callback_keys + newsk->sk_family,
1525 af_family_clock_key_strings[newsk->sk_family]);
1526
1527 newsk->sk_dst_cache = NULL;
1528 newsk->sk_wmem_queued = 0;
1529 newsk->sk_forward_alloc = 0;
1530 newsk->sk_send_head = NULL;
1531 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1532
1533 sock_reset_flag(newsk, SOCK_DONE);
1534 skb_queue_head_init(&newsk->sk_error_queue);
1535
1536 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1537 if (filter != NULL)
1538 /* though it's an empty new sock, the charging may fail
1539 * if sysctl_optmem_max was changed between creation of
1540 * original socket and cloning
1541 */
1542 is_charged = sk_filter_charge(newsk, filter);
1543
1544 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) {
1545 /* It is still raw copy of parent, so invalidate
1546 * destructor and make plain sk_free() */
1547 newsk->sk_destruct = NULL;
1548 bh_unlock_sock(newsk);
1549 sk_free(newsk);
1550 newsk = NULL;
1551 goto out;
1552 }
1553
1554 newsk->sk_err = 0;
1555 newsk->sk_priority = 0;
1556 newsk->sk_incoming_cpu = raw_smp_processor_id();
1557 atomic64_set(&newsk->sk_cookie, 0);
1558 /*
1559 * Before updating sk_refcnt, we must commit prior changes to memory
1560 * (Documentation/RCU/rculist_nulls.txt for details)
1561 */
1562 smp_wmb();
1563 atomic_set(&newsk->sk_refcnt, 2);
1564
1565 /*
1566 * Increment the counter in the same struct proto as the master
1567 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1568 * is the same as sk->sk_prot->socks, as this field was copied
1569 * with memcpy).
1570 *
1571 * This _changes_ the previous behaviour, where
1572 * tcp_create_openreq_child always was incrementing the
1573 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1574 * to be taken into account in all callers. -acme
1575 */
1576 sk_refcnt_debug_inc(newsk);
1577 sk_set_socket(newsk, NULL);
1578 newsk->sk_wq = NULL;
1579
1580 sk_update_clone(sk, newsk);
1581
1582 if (newsk->sk_prot->sockets_allocated)
1583 sk_sockets_allocated_inc(newsk);
1584
1585 if (sock_needs_netstamp(sk) &&
1586 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1587 net_enable_timestamp();
1588 }
1589 out:
1590 return newsk;
1591 }
1592 EXPORT_SYMBOL_GPL(sk_clone_lock);
1593
1594 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1595 {
1596 u32 max_segs = 1;
1597
1598 sk_dst_set(sk, dst);
1599 sk->sk_route_caps = dst->dev->features;
1600 if (sk->sk_route_caps & NETIF_F_GSO)
1601 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1602 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1603 if (sk_can_gso(sk)) {
1604 if (dst->header_len) {
1605 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1606 } else {
1607 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1608 sk->sk_gso_max_size = dst->dev->gso_max_size;
1609 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1610 }
1611 }
1612 sk->sk_gso_max_segs = max_segs;
1613 }
1614 EXPORT_SYMBOL_GPL(sk_setup_caps);
1615
1616 /*
1617 * Simple resource managers for sockets.
1618 */
1619
1620
1621 /*
1622 * Write buffer destructor automatically called from kfree_skb.
1623 */
1624 void sock_wfree(struct sk_buff *skb)
1625 {
1626 struct sock *sk = skb->sk;
1627 unsigned int len = skb->truesize;
1628
1629 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1630 /*
1631 * Keep a reference on sk_wmem_alloc, this will be released
1632 * after sk_write_space() call
1633 */
1634 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1635 sk->sk_write_space(sk);
1636 len = 1;
1637 }
1638 /*
1639 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1640 * could not do because of in-flight packets
1641 */
1642 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1643 __sk_free(sk);
1644 }
1645 EXPORT_SYMBOL(sock_wfree);
1646
1647 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1648 {
1649 skb_orphan(skb);
1650 skb->sk = sk;
1651 #ifdef CONFIG_INET
1652 if (unlikely(!sk_fullsock(sk))) {
1653 skb->destructor = sock_edemux;
1654 sock_hold(sk);
1655 return;
1656 }
1657 #endif
1658 skb->destructor = sock_wfree;
1659 skb_set_hash_from_sk(skb, sk);
1660 /*
1661 * We used to take a refcount on sk, but following operation
1662 * is enough to guarantee sk_free() wont free this sock until
1663 * all in-flight packets are completed
1664 */
1665 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1666 }
1667 EXPORT_SYMBOL(skb_set_owner_w);
1668
1669 void skb_orphan_partial(struct sk_buff *skb)
1670 {
1671 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1672 * so we do not completely orphan skb, but transfert all
1673 * accounted bytes but one, to avoid unexpected reorders.
1674 */
1675 if (skb->destructor == sock_wfree
1676 #ifdef CONFIG_INET
1677 || skb->destructor == tcp_wfree
1678 #endif
1679 ) {
1680 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1681 skb->truesize = 1;
1682 } else {
1683 skb_orphan(skb);
1684 }
1685 }
1686 EXPORT_SYMBOL(skb_orphan_partial);
1687
1688 /*
1689 * Read buffer destructor automatically called from kfree_skb.
1690 */
1691 void sock_rfree(struct sk_buff *skb)
1692 {
1693 struct sock *sk = skb->sk;
1694 unsigned int len = skb->truesize;
1695
1696 atomic_sub(len, &sk->sk_rmem_alloc);
1697 sk_mem_uncharge(sk, len);
1698 }
1699 EXPORT_SYMBOL(sock_rfree);
1700
1701 /*
1702 * Buffer destructor for skbs that are not used directly in read or write
1703 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1704 */
1705 void sock_efree(struct sk_buff *skb)
1706 {
1707 sock_put(skb->sk);
1708 }
1709 EXPORT_SYMBOL(sock_efree);
1710
1711 kuid_t sock_i_uid(struct sock *sk)
1712 {
1713 kuid_t uid;
1714
1715 read_lock_bh(&sk->sk_callback_lock);
1716 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1717 read_unlock_bh(&sk->sk_callback_lock);
1718 return uid;
1719 }
1720 EXPORT_SYMBOL(sock_i_uid);
1721
1722 unsigned long sock_i_ino(struct sock *sk)
1723 {
1724 unsigned long ino;
1725
1726 read_lock_bh(&sk->sk_callback_lock);
1727 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1728 read_unlock_bh(&sk->sk_callback_lock);
1729 return ino;
1730 }
1731 EXPORT_SYMBOL(sock_i_ino);
1732
1733 /*
1734 * Allocate a skb from the socket's send buffer.
1735 */
1736 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1737 gfp_t priority)
1738 {
1739 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1740 struct sk_buff *skb = alloc_skb(size, priority);
1741 if (skb) {
1742 skb_set_owner_w(skb, sk);
1743 return skb;
1744 }
1745 }
1746 return NULL;
1747 }
1748 EXPORT_SYMBOL(sock_wmalloc);
1749
1750 /*
1751 * Allocate a memory block from the socket's option memory buffer.
1752 */
1753 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1754 {
1755 if ((unsigned int)size <= sysctl_optmem_max &&
1756 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1757 void *mem;
1758 /* First do the add, to avoid the race if kmalloc
1759 * might sleep.
1760 */
1761 atomic_add(size, &sk->sk_omem_alloc);
1762 mem = kmalloc(size, priority);
1763 if (mem)
1764 return mem;
1765 atomic_sub(size, &sk->sk_omem_alloc);
1766 }
1767 return NULL;
1768 }
1769 EXPORT_SYMBOL(sock_kmalloc);
1770
1771 /* Free an option memory block. Note, we actually want the inline
1772 * here as this allows gcc to detect the nullify and fold away the
1773 * condition entirely.
1774 */
1775 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1776 const bool nullify)
1777 {
1778 if (WARN_ON_ONCE(!mem))
1779 return;
1780 if (nullify)
1781 kzfree(mem);
1782 else
1783 kfree(mem);
1784 atomic_sub(size, &sk->sk_omem_alloc);
1785 }
1786
1787 void sock_kfree_s(struct sock *sk, void *mem, int size)
1788 {
1789 __sock_kfree_s(sk, mem, size, false);
1790 }
1791 EXPORT_SYMBOL(sock_kfree_s);
1792
1793 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1794 {
1795 __sock_kfree_s(sk, mem, size, true);
1796 }
1797 EXPORT_SYMBOL(sock_kzfree_s);
1798
1799 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1800 I think, these locks should be removed for datagram sockets.
1801 */
1802 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1803 {
1804 DEFINE_WAIT(wait);
1805
1806 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1807 for (;;) {
1808 if (!timeo)
1809 break;
1810 if (signal_pending(current))
1811 break;
1812 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1813 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1814 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1815 break;
1816 if (sk->sk_shutdown & SEND_SHUTDOWN)
1817 break;
1818 if (sk->sk_err)
1819 break;
1820 timeo = schedule_timeout(timeo);
1821 }
1822 finish_wait(sk_sleep(sk), &wait);
1823 return timeo;
1824 }
1825
1826
1827 /*
1828 * Generic send/receive buffer handlers
1829 */
1830
1831 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1832 unsigned long data_len, int noblock,
1833 int *errcode, int max_page_order)
1834 {
1835 struct sk_buff *skb;
1836 long timeo;
1837 int err;
1838
1839 timeo = sock_sndtimeo(sk, noblock);
1840 for (;;) {
1841 err = sock_error(sk);
1842 if (err != 0)
1843 goto failure;
1844
1845 err = -EPIPE;
1846 if (sk->sk_shutdown & SEND_SHUTDOWN)
1847 goto failure;
1848
1849 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1850 break;
1851
1852 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1853 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1854 err = -EAGAIN;
1855 if (!timeo)
1856 goto failure;
1857 if (signal_pending(current))
1858 goto interrupted;
1859 timeo = sock_wait_for_wmem(sk, timeo);
1860 }
1861 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1862 errcode, sk->sk_allocation);
1863 if (skb)
1864 skb_set_owner_w(skb, sk);
1865 return skb;
1866
1867 interrupted:
1868 err = sock_intr_errno(timeo);
1869 failure:
1870 *errcode = err;
1871 return NULL;
1872 }
1873 EXPORT_SYMBOL(sock_alloc_send_pskb);
1874
1875 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1876 int noblock, int *errcode)
1877 {
1878 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1879 }
1880 EXPORT_SYMBOL(sock_alloc_send_skb);
1881
1882 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1883 struct sockcm_cookie *sockc)
1884 {
1885 struct cmsghdr *cmsg;
1886
1887 for_each_cmsghdr(cmsg, msg) {
1888 if (!CMSG_OK(msg, cmsg))
1889 return -EINVAL;
1890 if (cmsg->cmsg_level != SOL_SOCKET)
1891 continue;
1892 switch (cmsg->cmsg_type) {
1893 case SO_MARK:
1894 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1895 return -EPERM;
1896 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1897 return -EINVAL;
1898 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
1899 break;
1900 default:
1901 return -EINVAL;
1902 }
1903 }
1904 return 0;
1905 }
1906 EXPORT_SYMBOL(sock_cmsg_send);
1907
1908 /* On 32bit arches, an skb frag is limited to 2^15 */
1909 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1910
1911 /**
1912 * skb_page_frag_refill - check that a page_frag contains enough room
1913 * @sz: minimum size of the fragment we want to get
1914 * @pfrag: pointer to page_frag
1915 * @gfp: priority for memory allocation
1916 *
1917 * Note: While this allocator tries to use high order pages, there is
1918 * no guarantee that allocations succeed. Therefore, @sz MUST be
1919 * less or equal than PAGE_SIZE.
1920 */
1921 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1922 {
1923 if (pfrag->page) {
1924 if (atomic_read(&pfrag->page->_count) == 1) {
1925 pfrag->offset = 0;
1926 return true;
1927 }
1928 if (pfrag->offset + sz <= pfrag->size)
1929 return true;
1930 put_page(pfrag->page);
1931 }
1932
1933 pfrag->offset = 0;
1934 if (SKB_FRAG_PAGE_ORDER) {
1935 /* Avoid direct reclaim but allow kswapd to wake */
1936 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
1937 __GFP_COMP | __GFP_NOWARN |
1938 __GFP_NORETRY,
1939 SKB_FRAG_PAGE_ORDER);
1940 if (likely(pfrag->page)) {
1941 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1942 return true;
1943 }
1944 }
1945 pfrag->page = alloc_page(gfp);
1946 if (likely(pfrag->page)) {
1947 pfrag->size = PAGE_SIZE;
1948 return true;
1949 }
1950 return false;
1951 }
1952 EXPORT_SYMBOL(skb_page_frag_refill);
1953
1954 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1955 {
1956 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1957 return true;
1958
1959 sk_enter_memory_pressure(sk);
1960 sk_stream_moderate_sndbuf(sk);
1961 return false;
1962 }
1963 EXPORT_SYMBOL(sk_page_frag_refill);
1964
1965 static void __lock_sock(struct sock *sk)
1966 __releases(&sk->sk_lock.slock)
1967 __acquires(&sk->sk_lock.slock)
1968 {
1969 DEFINE_WAIT(wait);
1970
1971 for (;;) {
1972 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1973 TASK_UNINTERRUPTIBLE);
1974 spin_unlock_bh(&sk->sk_lock.slock);
1975 schedule();
1976 spin_lock_bh(&sk->sk_lock.slock);
1977 if (!sock_owned_by_user(sk))
1978 break;
1979 }
1980 finish_wait(&sk->sk_lock.wq, &wait);
1981 }
1982
1983 static void __release_sock(struct sock *sk)
1984 __releases(&sk->sk_lock.slock)
1985 __acquires(&sk->sk_lock.slock)
1986 {
1987 struct sk_buff *skb = sk->sk_backlog.head;
1988
1989 do {
1990 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1991 bh_unlock_sock(sk);
1992
1993 do {
1994 struct sk_buff *next = skb->next;
1995
1996 prefetch(next);
1997 WARN_ON_ONCE(skb_dst_is_noref(skb));
1998 skb->next = NULL;
1999 sk_backlog_rcv(sk, skb);
2000
2001 /*
2002 * We are in process context here with softirqs
2003 * disabled, use cond_resched_softirq() to preempt.
2004 * This is safe to do because we've taken the backlog
2005 * queue private:
2006 */
2007 cond_resched_softirq();
2008
2009 skb = next;
2010 } while (skb != NULL);
2011
2012 bh_lock_sock(sk);
2013 } while ((skb = sk->sk_backlog.head) != NULL);
2014
2015 /*
2016 * Doing the zeroing here guarantee we can not loop forever
2017 * while a wild producer attempts to flood us.
2018 */
2019 sk->sk_backlog.len = 0;
2020 }
2021
2022 /**
2023 * sk_wait_data - wait for data to arrive at sk_receive_queue
2024 * @sk: sock to wait on
2025 * @timeo: for how long
2026 * @skb: last skb seen on sk_receive_queue
2027 *
2028 * Now socket state including sk->sk_err is changed only under lock,
2029 * hence we may omit checks after joining wait queue.
2030 * We check receive queue before schedule() only as optimization;
2031 * it is very likely that release_sock() added new data.
2032 */
2033 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2034 {
2035 int rc;
2036 DEFINE_WAIT(wait);
2037
2038 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2039 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2040 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb);
2041 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2042 finish_wait(sk_sleep(sk), &wait);
2043 return rc;
2044 }
2045 EXPORT_SYMBOL(sk_wait_data);
2046
2047 /**
2048 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2049 * @sk: socket
2050 * @size: memory size to allocate
2051 * @kind: allocation type
2052 *
2053 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2054 * rmem allocation. This function assumes that protocols which have
2055 * memory_pressure use sk_wmem_queued as write buffer accounting.
2056 */
2057 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2058 {
2059 struct proto *prot = sk->sk_prot;
2060 int amt = sk_mem_pages(size);
2061 long allocated;
2062 int parent_status = UNDER_LIMIT;
2063
2064 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2065
2066 allocated = sk_memory_allocated_add(sk, amt, &parent_status);
2067
2068 /* Under limit. */
2069 if (parent_status == UNDER_LIMIT &&
2070 allocated <= sk_prot_mem_limits(sk, 0)) {
2071 sk_leave_memory_pressure(sk);
2072 return 1;
2073 }
2074
2075 /* Under pressure. (we or our parents) */
2076 if ((parent_status > SOFT_LIMIT) ||
2077 allocated > sk_prot_mem_limits(sk, 1))
2078 sk_enter_memory_pressure(sk);
2079
2080 /* Over hard limit (we or our parents) */
2081 if ((parent_status == OVER_LIMIT) ||
2082 (allocated > sk_prot_mem_limits(sk, 2)))
2083 goto suppress_allocation;
2084
2085 /* guarantee minimum buffer size under pressure */
2086 if (kind == SK_MEM_RECV) {
2087 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2088 return 1;
2089
2090 } else { /* SK_MEM_SEND */
2091 if (sk->sk_type == SOCK_STREAM) {
2092 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2093 return 1;
2094 } else if (atomic_read(&sk->sk_wmem_alloc) <
2095 prot->sysctl_wmem[0])
2096 return 1;
2097 }
2098
2099 if (sk_has_memory_pressure(sk)) {
2100 int alloc;
2101
2102 if (!sk_under_memory_pressure(sk))
2103 return 1;
2104 alloc = sk_sockets_allocated_read_positive(sk);
2105 if (sk_prot_mem_limits(sk, 2) > alloc *
2106 sk_mem_pages(sk->sk_wmem_queued +
2107 atomic_read(&sk->sk_rmem_alloc) +
2108 sk->sk_forward_alloc))
2109 return 1;
2110 }
2111
2112 suppress_allocation:
2113
2114 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2115 sk_stream_moderate_sndbuf(sk);
2116
2117 /* Fail only if socket is _under_ its sndbuf.
2118 * In this case we cannot block, so that we have to fail.
2119 */
2120 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2121 return 1;
2122 }
2123
2124 trace_sock_exceed_buf_limit(sk, prot, allocated);
2125
2126 /* Alas. Undo changes. */
2127 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2128
2129 sk_memory_allocated_sub(sk, amt);
2130
2131 return 0;
2132 }
2133 EXPORT_SYMBOL(__sk_mem_schedule);
2134
2135 /**
2136 * __sk_mem_reclaim - reclaim memory_allocated
2137 * @sk: socket
2138 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2139 */
2140 void __sk_mem_reclaim(struct sock *sk, int amount)
2141 {
2142 amount >>= SK_MEM_QUANTUM_SHIFT;
2143 sk_memory_allocated_sub(sk, amount);
2144 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2145
2146 if (sk_under_memory_pressure(sk) &&
2147 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2148 sk_leave_memory_pressure(sk);
2149 }
2150 EXPORT_SYMBOL(__sk_mem_reclaim);
2151
2152
2153 /*
2154 * Set of default routines for initialising struct proto_ops when
2155 * the protocol does not support a particular function. In certain
2156 * cases where it makes no sense for a protocol to have a "do nothing"
2157 * function, some default processing is provided.
2158 */
2159
2160 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2161 {
2162 return -EOPNOTSUPP;
2163 }
2164 EXPORT_SYMBOL(sock_no_bind);
2165
2166 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2167 int len, int flags)
2168 {
2169 return -EOPNOTSUPP;
2170 }
2171 EXPORT_SYMBOL(sock_no_connect);
2172
2173 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2174 {
2175 return -EOPNOTSUPP;
2176 }
2177 EXPORT_SYMBOL(sock_no_socketpair);
2178
2179 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2180 {
2181 return -EOPNOTSUPP;
2182 }
2183 EXPORT_SYMBOL(sock_no_accept);
2184
2185 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2186 int *len, int peer)
2187 {
2188 return -EOPNOTSUPP;
2189 }
2190 EXPORT_SYMBOL(sock_no_getname);
2191
2192 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2193 {
2194 return 0;
2195 }
2196 EXPORT_SYMBOL(sock_no_poll);
2197
2198 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2199 {
2200 return -EOPNOTSUPP;
2201 }
2202 EXPORT_SYMBOL(sock_no_ioctl);
2203
2204 int sock_no_listen(struct socket *sock, int backlog)
2205 {
2206 return -EOPNOTSUPP;
2207 }
2208 EXPORT_SYMBOL(sock_no_listen);
2209
2210 int sock_no_shutdown(struct socket *sock, int how)
2211 {
2212 return -EOPNOTSUPP;
2213 }
2214 EXPORT_SYMBOL(sock_no_shutdown);
2215
2216 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2217 char __user *optval, unsigned int optlen)
2218 {
2219 return -EOPNOTSUPP;
2220 }
2221 EXPORT_SYMBOL(sock_no_setsockopt);
2222
2223 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2224 char __user *optval, int __user *optlen)
2225 {
2226 return -EOPNOTSUPP;
2227 }
2228 EXPORT_SYMBOL(sock_no_getsockopt);
2229
2230 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2231 {
2232 return -EOPNOTSUPP;
2233 }
2234 EXPORT_SYMBOL(sock_no_sendmsg);
2235
2236 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2237 int flags)
2238 {
2239 return -EOPNOTSUPP;
2240 }
2241 EXPORT_SYMBOL(sock_no_recvmsg);
2242
2243 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2244 {
2245 /* Mirror missing mmap method error code */
2246 return -ENODEV;
2247 }
2248 EXPORT_SYMBOL(sock_no_mmap);
2249
2250 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2251 {
2252 ssize_t res;
2253 struct msghdr msg = {.msg_flags = flags};
2254 struct kvec iov;
2255 char *kaddr = kmap(page);
2256 iov.iov_base = kaddr + offset;
2257 iov.iov_len = size;
2258 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2259 kunmap(page);
2260 return res;
2261 }
2262 EXPORT_SYMBOL(sock_no_sendpage);
2263
2264 /*
2265 * Default Socket Callbacks
2266 */
2267
2268 static void sock_def_wakeup(struct sock *sk)
2269 {
2270 struct socket_wq *wq;
2271
2272 rcu_read_lock();
2273 wq = rcu_dereference(sk->sk_wq);
2274 if (skwq_has_sleeper(wq))
2275 wake_up_interruptible_all(&wq->wait);
2276 rcu_read_unlock();
2277 }
2278
2279 static void sock_def_error_report(struct sock *sk)
2280 {
2281 struct socket_wq *wq;
2282
2283 rcu_read_lock();
2284 wq = rcu_dereference(sk->sk_wq);
2285 if (skwq_has_sleeper(wq))
2286 wake_up_interruptible_poll(&wq->wait, POLLERR);
2287 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2288 rcu_read_unlock();
2289 }
2290
2291 static void sock_def_readable(struct sock *sk)
2292 {
2293 struct socket_wq *wq;
2294
2295 rcu_read_lock();
2296 wq = rcu_dereference(sk->sk_wq);
2297 if (skwq_has_sleeper(wq))
2298 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2299 POLLRDNORM | POLLRDBAND);
2300 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2301 rcu_read_unlock();
2302 }
2303
2304 static void sock_def_write_space(struct sock *sk)
2305 {
2306 struct socket_wq *wq;
2307
2308 rcu_read_lock();
2309
2310 /* Do not wake up a writer until he can make "significant"
2311 * progress. --DaveM
2312 */
2313 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2314 wq = rcu_dereference(sk->sk_wq);
2315 if (skwq_has_sleeper(wq))
2316 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2317 POLLWRNORM | POLLWRBAND);
2318
2319 /* Should agree with poll, otherwise some programs break */
2320 if (sock_writeable(sk))
2321 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2322 }
2323
2324 rcu_read_unlock();
2325 }
2326
2327 static void sock_def_destruct(struct sock *sk)
2328 {
2329 }
2330
2331 void sk_send_sigurg(struct sock *sk)
2332 {
2333 if (sk->sk_socket && sk->sk_socket->file)
2334 if (send_sigurg(&sk->sk_socket->file->f_owner))
2335 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2336 }
2337 EXPORT_SYMBOL(sk_send_sigurg);
2338
2339 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2340 unsigned long expires)
2341 {
2342 if (!mod_timer(timer, expires))
2343 sock_hold(sk);
2344 }
2345 EXPORT_SYMBOL(sk_reset_timer);
2346
2347 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2348 {
2349 if (del_timer(timer))
2350 __sock_put(sk);
2351 }
2352 EXPORT_SYMBOL(sk_stop_timer);
2353
2354 void sock_init_data(struct socket *sock, struct sock *sk)
2355 {
2356 skb_queue_head_init(&sk->sk_receive_queue);
2357 skb_queue_head_init(&sk->sk_write_queue);
2358 skb_queue_head_init(&sk->sk_error_queue);
2359
2360 sk->sk_send_head = NULL;
2361
2362 init_timer(&sk->sk_timer);
2363
2364 sk->sk_allocation = GFP_KERNEL;
2365 sk->sk_rcvbuf = sysctl_rmem_default;
2366 sk->sk_sndbuf = sysctl_wmem_default;
2367 sk->sk_state = TCP_CLOSE;
2368 sk_set_socket(sk, sock);
2369
2370 sock_set_flag(sk, SOCK_ZAPPED);
2371
2372 if (sock) {
2373 sk->sk_type = sock->type;
2374 sk->sk_wq = sock->wq;
2375 sock->sk = sk;
2376 } else
2377 sk->sk_wq = NULL;
2378
2379 rwlock_init(&sk->sk_callback_lock);
2380 lockdep_set_class_and_name(&sk->sk_callback_lock,
2381 af_callback_keys + sk->sk_family,
2382 af_family_clock_key_strings[sk->sk_family]);
2383
2384 sk->sk_state_change = sock_def_wakeup;
2385 sk->sk_data_ready = sock_def_readable;
2386 sk->sk_write_space = sock_def_write_space;
2387 sk->sk_error_report = sock_def_error_report;
2388 sk->sk_destruct = sock_def_destruct;
2389
2390 sk->sk_frag.page = NULL;
2391 sk->sk_frag.offset = 0;
2392 sk->sk_peek_off = -1;
2393
2394 sk->sk_peer_pid = NULL;
2395 sk->sk_peer_cred = NULL;
2396 sk->sk_write_pending = 0;
2397 sk->sk_rcvlowat = 1;
2398 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2399 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2400
2401 sk->sk_stamp = ktime_set(-1L, 0);
2402
2403 #ifdef CONFIG_NET_RX_BUSY_POLL
2404 sk->sk_napi_id = 0;
2405 sk->sk_ll_usec = sysctl_net_busy_read;
2406 #endif
2407
2408 sk->sk_max_pacing_rate = ~0U;
2409 sk->sk_pacing_rate = ~0U;
2410 sk->sk_incoming_cpu = -1;
2411 /*
2412 * Before updating sk_refcnt, we must commit prior changes to memory
2413 * (Documentation/RCU/rculist_nulls.txt for details)
2414 */
2415 smp_wmb();
2416 atomic_set(&sk->sk_refcnt, 1);
2417 atomic_set(&sk->sk_drops, 0);
2418 }
2419 EXPORT_SYMBOL(sock_init_data);
2420
2421 void lock_sock_nested(struct sock *sk, int subclass)
2422 {
2423 might_sleep();
2424 spin_lock_bh(&sk->sk_lock.slock);
2425 if (sk->sk_lock.owned)
2426 __lock_sock(sk);
2427 sk->sk_lock.owned = 1;
2428 spin_unlock(&sk->sk_lock.slock);
2429 /*
2430 * The sk_lock has mutex_lock() semantics here:
2431 */
2432 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2433 local_bh_enable();
2434 }
2435 EXPORT_SYMBOL(lock_sock_nested);
2436
2437 void release_sock(struct sock *sk)
2438 {
2439 /*
2440 * The sk_lock has mutex_unlock() semantics:
2441 */
2442 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2443
2444 spin_lock_bh(&sk->sk_lock.slock);
2445 if (sk->sk_backlog.tail)
2446 __release_sock(sk);
2447
2448 /* Warning : release_cb() might need to release sk ownership,
2449 * ie call sock_release_ownership(sk) before us.
2450 */
2451 if (sk->sk_prot->release_cb)
2452 sk->sk_prot->release_cb(sk);
2453
2454 sock_release_ownership(sk);
2455 if (waitqueue_active(&sk->sk_lock.wq))
2456 wake_up(&sk->sk_lock.wq);
2457 spin_unlock_bh(&sk->sk_lock.slock);
2458 }
2459 EXPORT_SYMBOL(release_sock);
2460
2461 /**
2462 * lock_sock_fast - fast version of lock_sock
2463 * @sk: socket
2464 *
2465 * This version should be used for very small section, where process wont block
2466 * return false if fast path is taken
2467 * sk_lock.slock locked, owned = 0, BH disabled
2468 * return true if slow path is taken
2469 * sk_lock.slock unlocked, owned = 1, BH enabled
2470 */
2471 bool lock_sock_fast(struct sock *sk)
2472 {
2473 might_sleep();
2474 spin_lock_bh(&sk->sk_lock.slock);
2475
2476 if (!sk->sk_lock.owned)
2477 /*
2478 * Note : We must disable BH
2479 */
2480 return false;
2481
2482 __lock_sock(sk);
2483 sk->sk_lock.owned = 1;
2484 spin_unlock(&sk->sk_lock.slock);
2485 /*
2486 * The sk_lock has mutex_lock() semantics here:
2487 */
2488 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2489 local_bh_enable();
2490 return true;
2491 }
2492 EXPORT_SYMBOL(lock_sock_fast);
2493
2494 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2495 {
2496 struct timeval tv;
2497 if (!sock_flag(sk, SOCK_TIMESTAMP))
2498 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2499 tv = ktime_to_timeval(sk->sk_stamp);
2500 if (tv.tv_sec == -1)
2501 return -ENOENT;
2502 if (tv.tv_sec == 0) {
2503 sk->sk_stamp = ktime_get_real();
2504 tv = ktime_to_timeval(sk->sk_stamp);
2505 }
2506 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2507 }
2508 EXPORT_SYMBOL(sock_get_timestamp);
2509
2510 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2511 {
2512 struct timespec ts;
2513 if (!sock_flag(sk, SOCK_TIMESTAMP))
2514 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2515 ts = ktime_to_timespec(sk->sk_stamp);
2516 if (ts.tv_sec == -1)
2517 return -ENOENT;
2518 if (ts.tv_sec == 0) {
2519 sk->sk_stamp = ktime_get_real();
2520 ts = ktime_to_timespec(sk->sk_stamp);
2521 }
2522 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2523 }
2524 EXPORT_SYMBOL(sock_get_timestampns);
2525
2526 void sock_enable_timestamp(struct sock *sk, int flag)
2527 {
2528 if (!sock_flag(sk, flag)) {
2529 unsigned long previous_flags = sk->sk_flags;
2530
2531 sock_set_flag(sk, flag);
2532 /*
2533 * we just set one of the two flags which require net
2534 * time stamping, but time stamping might have been on
2535 * already because of the other one
2536 */
2537 if (sock_needs_netstamp(sk) &&
2538 !(previous_flags & SK_FLAGS_TIMESTAMP))
2539 net_enable_timestamp();
2540 }
2541 }
2542
2543 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2544 int level, int type)
2545 {
2546 struct sock_exterr_skb *serr;
2547 struct sk_buff *skb;
2548 int copied, err;
2549
2550 err = -EAGAIN;
2551 skb = sock_dequeue_err_skb(sk);
2552 if (skb == NULL)
2553 goto out;
2554
2555 copied = skb->len;
2556 if (copied > len) {
2557 msg->msg_flags |= MSG_TRUNC;
2558 copied = len;
2559 }
2560 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2561 if (err)
2562 goto out_free_skb;
2563
2564 sock_recv_timestamp(msg, sk, skb);
2565
2566 serr = SKB_EXT_ERR(skb);
2567 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2568
2569 msg->msg_flags |= MSG_ERRQUEUE;
2570 err = copied;
2571
2572 out_free_skb:
2573 kfree_skb(skb);
2574 out:
2575 return err;
2576 }
2577 EXPORT_SYMBOL(sock_recv_errqueue);
2578
2579 /*
2580 * Get a socket option on an socket.
2581 *
2582 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2583 * asynchronous errors should be reported by getsockopt. We assume
2584 * this means if you specify SO_ERROR (otherwise whats the point of it).
2585 */
2586 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2587 char __user *optval, int __user *optlen)
2588 {
2589 struct sock *sk = sock->sk;
2590
2591 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2592 }
2593 EXPORT_SYMBOL(sock_common_getsockopt);
2594
2595 #ifdef CONFIG_COMPAT
2596 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2597 char __user *optval, int __user *optlen)
2598 {
2599 struct sock *sk = sock->sk;
2600
2601 if (sk->sk_prot->compat_getsockopt != NULL)
2602 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2603 optval, optlen);
2604 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2605 }
2606 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2607 #endif
2608
2609 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2610 int flags)
2611 {
2612 struct sock *sk = sock->sk;
2613 int addr_len = 0;
2614 int err;
2615
2616 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2617 flags & ~MSG_DONTWAIT, &addr_len);
2618 if (err >= 0)
2619 msg->msg_namelen = addr_len;
2620 return err;
2621 }
2622 EXPORT_SYMBOL(sock_common_recvmsg);
2623
2624 /*
2625 * Set socket options on an inet socket.
2626 */
2627 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2628 char __user *optval, unsigned int optlen)
2629 {
2630 struct sock *sk = sock->sk;
2631
2632 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2633 }
2634 EXPORT_SYMBOL(sock_common_setsockopt);
2635
2636 #ifdef CONFIG_COMPAT
2637 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2638 char __user *optval, unsigned int optlen)
2639 {
2640 struct sock *sk = sock->sk;
2641
2642 if (sk->sk_prot->compat_setsockopt != NULL)
2643 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2644 optval, optlen);
2645 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2646 }
2647 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2648 #endif
2649
2650 void sk_common_release(struct sock *sk)
2651 {
2652 if (sk->sk_prot->destroy)
2653 sk->sk_prot->destroy(sk);
2654
2655 /*
2656 * Observation: when sock_common_release is called, processes have
2657 * no access to socket. But net still has.
2658 * Step one, detach it from networking:
2659 *
2660 * A. Remove from hash tables.
2661 */
2662
2663 sk->sk_prot->unhash(sk);
2664
2665 /*
2666 * In this point socket cannot receive new packets, but it is possible
2667 * that some packets are in flight because some CPU runs receiver and
2668 * did hash table lookup before we unhashed socket. They will achieve
2669 * receive queue and will be purged by socket destructor.
2670 *
2671 * Also we still have packets pending on receive queue and probably,
2672 * our own packets waiting in device queues. sock_destroy will drain
2673 * receive queue, but transmitted packets will delay socket destruction
2674 * until the last reference will be released.
2675 */
2676
2677 sock_orphan(sk);
2678
2679 xfrm_sk_free_policy(sk);
2680
2681 sk_refcnt_debug_release(sk);
2682
2683 if (sk->sk_frag.page) {
2684 put_page(sk->sk_frag.page);
2685 sk->sk_frag.page = NULL;
2686 }
2687
2688 sock_put(sk);
2689 }
2690 EXPORT_SYMBOL(sk_common_release);
2691
2692 #ifdef CONFIG_PROC_FS
2693 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2694 struct prot_inuse {
2695 int val[PROTO_INUSE_NR];
2696 };
2697
2698 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2699
2700 #ifdef CONFIG_NET_NS
2701 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2702 {
2703 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2704 }
2705 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2706
2707 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2708 {
2709 int cpu, idx = prot->inuse_idx;
2710 int res = 0;
2711
2712 for_each_possible_cpu(cpu)
2713 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2714
2715 return res >= 0 ? res : 0;
2716 }
2717 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2718
2719 static int __net_init sock_inuse_init_net(struct net *net)
2720 {
2721 net->core.inuse = alloc_percpu(struct prot_inuse);
2722 return net->core.inuse ? 0 : -ENOMEM;
2723 }
2724
2725 static void __net_exit sock_inuse_exit_net(struct net *net)
2726 {
2727 free_percpu(net->core.inuse);
2728 }
2729
2730 static struct pernet_operations net_inuse_ops = {
2731 .init = sock_inuse_init_net,
2732 .exit = sock_inuse_exit_net,
2733 };
2734
2735 static __init int net_inuse_init(void)
2736 {
2737 if (register_pernet_subsys(&net_inuse_ops))
2738 panic("Cannot initialize net inuse counters");
2739
2740 return 0;
2741 }
2742
2743 core_initcall(net_inuse_init);
2744 #else
2745 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2746
2747 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2748 {
2749 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2750 }
2751 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2752
2753 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2754 {
2755 int cpu, idx = prot->inuse_idx;
2756 int res = 0;
2757
2758 for_each_possible_cpu(cpu)
2759 res += per_cpu(prot_inuse, cpu).val[idx];
2760
2761 return res >= 0 ? res : 0;
2762 }
2763 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2764 #endif
2765
2766 static void assign_proto_idx(struct proto *prot)
2767 {
2768 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2769
2770 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2771 pr_err("PROTO_INUSE_NR exhausted\n");
2772 return;
2773 }
2774
2775 set_bit(prot->inuse_idx, proto_inuse_idx);
2776 }
2777
2778 static void release_proto_idx(struct proto *prot)
2779 {
2780 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2781 clear_bit(prot->inuse_idx, proto_inuse_idx);
2782 }
2783 #else
2784 static inline void assign_proto_idx(struct proto *prot)
2785 {
2786 }
2787
2788 static inline void release_proto_idx(struct proto *prot)
2789 {
2790 }
2791 #endif
2792
2793 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2794 {
2795 if (!rsk_prot)
2796 return;
2797 kfree(rsk_prot->slab_name);
2798 rsk_prot->slab_name = NULL;
2799 kmem_cache_destroy(rsk_prot->slab);
2800 rsk_prot->slab = NULL;
2801 }
2802
2803 static int req_prot_init(const struct proto *prot)
2804 {
2805 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2806
2807 if (!rsk_prot)
2808 return 0;
2809
2810 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2811 prot->name);
2812 if (!rsk_prot->slab_name)
2813 return -ENOMEM;
2814
2815 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2816 rsk_prot->obj_size, 0,
2817 prot->slab_flags, NULL);
2818
2819 if (!rsk_prot->slab) {
2820 pr_crit("%s: Can't create request sock SLAB cache!\n",
2821 prot->name);
2822 return -ENOMEM;
2823 }
2824 return 0;
2825 }
2826
2827 int proto_register(struct proto *prot, int alloc_slab)
2828 {
2829 if (alloc_slab) {
2830 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2831 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2832 NULL);
2833
2834 if (prot->slab == NULL) {
2835 pr_crit("%s: Can't create sock SLAB cache!\n",
2836 prot->name);
2837 goto out;
2838 }
2839
2840 if (req_prot_init(prot))
2841 goto out_free_request_sock_slab;
2842
2843 if (prot->twsk_prot != NULL) {
2844 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2845
2846 if (prot->twsk_prot->twsk_slab_name == NULL)
2847 goto out_free_request_sock_slab;
2848
2849 prot->twsk_prot->twsk_slab =
2850 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2851 prot->twsk_prot->twsk_obj_size,
2852 0,
2853 prot->slab_flags,
2854 NULL);
2855 if (prot->twsk_prot->twsk_slab == NULL)
2856 goto out_free_timewait_sock_slab_name;
2857 }
2858 }
2859
2860 mutex_lock(&proto_list_mutex);
2861 list_add(&prot->node, &proto_list);
2862 assign_proto_idx(prot);
2863 mutex_unlock(&proto_list_mutex);
2864 return 0;
2865
2866 out_free_timewait_sock_slab_name:
2867 kfree(prot->twsk_prot->twsk_slab_name);
2868 out_free_request_sock_slab:
2869 req_prot_cleanup(prot->rsk_prot);
2870
2871 kmem_cache_destroy(prot->slab);
2872 prot->slab = NULL;
2873 out:
2874 return -ENOBUFS;
2875 }
2876 EXPORT_SYMBOL(proto_register);
2877
2878 void proto_unregister(struct proto *prot)
2879 {
2880 mutex_lock(&proto_list_mutex);
2881 release_proto_idx(prot);
2882 list_del(&prot->node);
2883 mutex_unlock(&proto_list_mutex);
2884
2885 kmem_cache_destroy(prot->slab);
2886 prot->slab = NULL;
2887
2888 req_prot_cleanup(prot->rsk_prot);
2889
2890 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2891 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2892 kfree(prot->twsk_prot->twsk_slab_name);
2893 prot->twsk_prot->twsk_slab = NULL;
2894 }
2895 }
2896 EXPORT_SYMBOL(proto_unregister);
2897
2898 #ifdef CONFIG_PROC_FS
2899 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2900 __acquires(proto_list_mutex)
2901 {
2902 mutex_lock(&proto_list_mutex);
2903 return seq_list_start_head(&proto_list, *pos);
2904 }
2905
2906 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2907 {
2908 return seq_list_next(v, &proto_list, pos);
2909 }
2910
2911 static void proto_seq_stop(struct seq_file *seq, void *v)
2912 __releases(proto_list_mutex)
2913 {
2914 mutex_unlock(&proto_list_mutex);
2915 }
2916
2917 static char proto_method_implemented(const void *method)
2918 {
2919 return method == NULL ? 'n' : 'y';
2920 }
2921 static long sock_prot_memory_allocated(struct proto *proto)
2922 {
2923 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2924 }
2925
2926 static char *sock_prot_memory_pressure(struct proto *proto)
2927 {
2928 return proto->memory_pressure != NULL ?
2929 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2930 }
2931
2932 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2933 {
2934
2935 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2936 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2937 proto->name,
2938 proto->obj_size,
2939 sock_prot_inuse_get(seq_file_net(seq), proto),
2940 sock_prot_memory_allocated(proto),
2941 sock_prot_memory_pressure(proto),
2942 proto->max_header,
2943 proto->slab == NULL ? "no" : "yes",
2944 module_name(proto->owner),
2945 proto_method_implemented(proto->close),
2946 proto_method_implemented(proto->connect),
2947 proto_method_implemented(proto->disconnect),
2948 proto_method_implemented(proto->accept),
2949 proto_method_implemented(proto->ioctl),
2950 proto_method_implemented(proto->init),
2951 proto_method_implemented(proto->destroy),
2952 proto_method_implemented(proto->shutdown),
2953 proto_method_implemented(proto->setsockopt),
2954 proto_method_implemented(proto->getsockopt),
2955 proto_method_implemented(proto->sendmsg),
2956 proto_method_implemented(proto->recvmsg),
2957 proto_method_implemented(proto->sendpage),
2958 proto_method_implemented(proto->bind),
2959 proto_method_implemented(proto->backlog_rcv),
2960 proto_method_implemented(proto->hash),
2961 proto_method_implemented(proto->unhash),
2962 proto_method_implemented(proto->get_port),
2963 proto_method_implemented(proto->enter_memory_pressure));
2964 }
2965
2966 static int proto_seq_show(struct seq_file *seq, void *v)
2967 {
2968 if (v == &proto_list)
2969 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2970 "protocol",
2971 "size",
2972 "sockets",
2973 "memory",
2974 "press",
2975 "maxhdr",
2976 "slab",
2977 "module",
2978 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2979 else
2980 proto_seq_printf(seq, list_entry(v, struct proto, node));
2981 return 0;
2982 }
2983
2984 static const struct seq_operations proto_seq_ops = {
2985 .start = proto_seq_start,
2986 .next = proto_seq_next,
2987 .stop = proto_seq_stop,
2988 .show = proto_seq_show,
2989 };
2990
2991 static int proto_seq_open(struct inode *inode, struct file *file)
2992 {
2993 return seq_open_net(inode, file, &proto_seq_ops,
2994 sizeof(struct seq_net_private));
2995 }
2996
2997 static const struct file_operations proto_seq_fops = {
2998 .owner = THIS_MODULE,
2999 .open = proto_seq_open,
3000 .read = seq_read,
3001 .llseek = seq_lseek,
3002 .release = seq_release_net,
3003 };
3004
3005 static __net_init int proto_init_net(struct net *net)
3006 {
3007 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3008 return -ENOMEM;
3009
3010 return 0;
3011 }
3012
3013 static __net_exit void proto_exit_net(struct net *net)
3014 {
3015 remove_proc_entry("protocols", net->proc_net);
3016 }
3017
3018
3019 static __net_initdata struct pernet_operations proto_net_ops = {
3020 .init = proto_init_net,
3021 .exit = proto_exit_net,
3022 };
3023
3024 static int __init proto_init(void)
3025 {
3026 return register_pernet_subsys(&proto_net_ops);
3027 }
3028
3029 subsys_initcall(proto_init);
3030
3031 #endif /* PROC_FS */
Linux kernel - Deliverables
This page took 0.134563 seconds and 5 git commands to generate.