]>
Commit | Line | Data |
---|---|---|
3f421baa ACM |
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 | * Support for INET connection oriented protocols. | |
7 | * | |
8 | * Authors: See the TCP sources | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public License | |
12 | * as published by the Free Software Foundation; either version | |
13 | * 2 of the License, or(at your option) any later version. | |
14 | */ | |
15 | ||
3f421baa ACM |
16 | #include <linux/module.h> |
17 | #include <linux/jhash.h> | |
18 | ||
19 | #include <net/inet_connection_sock.h> | |
20 | #include <net/inet_hashtables.h> | |
21 | #include <net/inet_timewait_sock.h> | |
22 | #include <net/ip.h> | |
23 | #include <net/route.h> | |
24 | #include <net/tcp_states.h> | |
a019d6fe | 25 | #include <net/xfrm.h> |
fa76ce73 | 26 | #include <net/tcp.h> |
3f421baa ACM |
27 | |
28 | #ifdef INET_CSK_DEBUG | |
29 | const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n"; | |
30 | EXPORT_SYMBOL(inet_csk_timer_bug_msg); | |
31 | #endif | |
32 | ||
0bbf87d8 | 33 | void inet_get_local_port_range(struct net *net, int *low, int *high) |
227b60f5 | 34 | { |
95c96174 ED |
35 | unsigned int seq; |
36 | ||
227b60f5 | 37 | do { |
c9d8f1a6 | 38 | seq = read_seqbegin(&net->ipv4.ip_local_ports.lock); |
227b60f5 | 39 | |
c9d8f1a6 CW |
40 | *low = net->ipv4.ip_local_ports.range[0]; |
41 | *high = net->ipv4.ip_local_ports.range[1]; | |
42 | } while (read_seqretry(&net->ipv4.ip_local_ports.lock, seq)); | |
227b60f5 SH |
43 | } |
44 | EXPORT_SYMBOL(inet_get_local_port_range); | |
3f421baa | 45 | |
971af18b | 46 | int inet_csk_bind_conflict(const struct sock *sk, |
aacd9289 | 47 | const struct inet_bind_bucket *tb, bool relax) |
3f421baa | 48 | { |
3f421baa | 49 | struct sock *sk2; |
3f421baa | 50 | int reuse = sk->sk_reuse; |
da5e3630 TH |
51 | int reuseport = sk->sk_reuseport; |
52 | kuid_t uid = sock_i_uid((struct sock *)sk); | |
3f421baa | 53 | |
7477fd2e PE |
54 | /* |
55 | * Unlike other sk lookup places we do not check | |
56 | * for sk_net here, since _all_ the socks listed | |
57 | * in tb->owners list belong to the same net - the | |
58 | * one this bucket belongs to. | |
59 | */ | |
60 | ||
b67bfe0d | 61 | sk_for_each_bound(sk2, &tb->owners) { |
3f421baa ACM |
62 | if (sk != sk2 && |
63 | !inet_v6_ipv6only(sk2) && | |
64 | (!sk->sk_bound_dev_if || | |
65 | !sk2->sk_bound_dev_if || | |
66 | sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) { | |
da5e3630 TH |
67 | if ((!reuse || !sk2->sk_reuse || |
68 | sk2->sk_state == TCP_LISTEN) && | |
69 | (!reuseport || !sk2->sk_reuseport || | |
70 | (sk2->sk_state != TCP_TIME_WAIT && | |
71 | !uid_eq(uid, sock_i_uid(sk2))))) { | |
50805466 ED |
72 | |
73 | if (!sk2->sk_rcv_saddr || !sk->sk_rcv_saddr || | |
74 | sk2->sk_rcv_saddr == sk->sk_rcv_saddr) | |
3f421baa | 75 | break; |
8d238b25 | 76 | } |
aacd9289 AC |
77 | if (!relax && reuse && sk2->sk_reuse && |
78 | sk2->sk_state != TCP_LISTEN) { | |
aacd9289 | 79 | |
50805466 ED |
80 | if (!sk2->sk_rcv_saddr || !sk->sk_rcv_saddr || |
81 | sk2->sk_rcv_saddr == sk->sk_rcv_saddr) | |
aacd9289 AC |
82 | break; |
83 | } | |
3f421baa ACM |
84 | } |
85 | } | |
b67bfe0d | 86 | return sk2 != NULL; |
3f421baa | 87 | } |
971af18b ACM |
88 | EXPORT_SYMBOL_GPL(inet_csk_bind_conflict); |
89 | ||
3f421baa ACM |
90 | /* Obtain a reference to a local port for the given sock, |
91 | * if snum is zero it means select any available local port. | |
92 | */ | |
ab1e0a13 | 93 | int inet_csk_get_port(struct sock *sk, unsigned short snum) |
3f421baa | 94 | { |
39d8cda7 | 95 | struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo; |
3f421baa | 96 | struct inet_bind_hashbucket *head; |
3f421baa | 97 | struct inet_bind_bucket *tb; |
a9d8f911 | 98 | int ret, attempts = 5; |
3b1e0a65 | 99 | struct net *net = sock_net(sk); |
a9d8f911 | 100 | int smallest_size = -1, smallest_rover; |
da5e3630 | 101 | kuid_t uid = sock_i_uid(sk); |
3f421baa ACM |
102 | |
103 | local_bh_disable(); | |
104 | if (!snum) { | |
227b60f5 SH |
105 | int remaining, rover, low, high; |
106 | ||
a9d8f911 | 107 | again: |
0bbf87d8 | 108 | inet_get_local_port_range(net, &low, &high); |
a25de534 | 109 | remaining = (high - low) + 1; |
63862b5b | 110 | smallest_rover = rover = prandom_u32() % remaining + low; |
3f421baa | 111 | |
a9d8f911 | 112 | smallest_size = -1; |
3f421baa | 113 | do { |
122ff243 | 114 | if (inet_is_local_reserved_port(net, rover)) |
e3826f1e | 115 | goto next_nolock; |
7f635ab7 PE |
116 | head = &hashinfo->bhash[inet_bhashfn(net, rover, |
117 | hashinfo->bhash_size)]; | |
3f421baa | 118 | spin_lock(&head->lock); |
b67bfe0d | 119 | inet_bind_bucket_for_each(tb, &head->chain) |
09ad9bc7 | 120 | if (net_eq(ib_net(tb), net) && tb->port == rover) { |
da5e3630 TH |
121 | if (((tb->fastreuse > 0 && |
122 | sk->sk_reuse && | |
123 | sk->sk_state != TCP_LISTEN) || | |
124 | (tb->fastreuseport > 0 && | |
125 | sk->sk_reuseport && | |
126 | uid_eq(tb->fastuid, uid))) && | |
a9d8f911 EP |
127 | (tb->num_owners < smallest_size || smallest_size == -1)) { |
128 | smallest_size = tb->num_owners; | |
129 | smallest_rover = rover; | |
aacd9289 AC |
130 | if (atomic_read(&hashinfo->bsockets) > (high - low) + 1 && |
131 | !inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false)) { | |
8d238b25 | 132 | snum = smallest_rover; |
fddb7b57 | 133 | goto tb_found; |
a9d8f911 EP |
134 | } |
135 | } | |
aacd9289 | 136 | if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false)) { |
2b05ad33 | 137 | snum = rover; |
fddb7b57 | 138 | goto tb_found; |
2b05ad33 | 139 | } |
3f421baa | 140 | goto next; |
a9d8f911 | 141 | } |
3f421baa ACM |
142 | break; |
143 | next: | |
144 | spin_unlock(&head->lock); | |
e3826f1e | 145 | next_nolock: |
6df71634 SH |
146 | if (++rover > high) |
147 | rover = low; | |
3f421baa | 148 | } while (--remaining > 0); |
3f421baa ACM |
149 | |
150 | /* Exhausted local port range during search? It is not | |
151 | * possible for us to be holding one of the bind hash | |
152 | * locks if this test triggers, because if 'remaining' | |
153 | * drops to zero, we broke out of the do/while loop at | |
154 | * the top level, not from the 'break;' statement. | |
155 | */ | |
156 | ret = 1; | |
a9d8f911 EP |
157 | if (remaining <= 0) { |
158 | if (smallest_size != -1) { | |
159 | snum = smallest_rover; | |
160 | goto have_snum; | |
161 | } | |
3f421baa | 162 | goto fail; |
a9d8f911 | 163 | } |
3f421baa ACM |
164 | /* OK, here is the one we will use. HEAD is |
165 | * non-NULL and we hold it's mutex. | |
166 | */ | |
167 | snum = rover; | |
168 | } else { | |
a9d8f911 | 169 | have_snum: |
7f635ab7 PE |
170 | head = &hashinfo->bhash[inet_bhashfn(net, snum, |
171 | hashinfo->bhash_size)]; | |
3f421baa | 172 | spin_lock(&head->lock); |
b67bfe0d | 173 | inet_bind_bucket_for_each(tb, &head->chain) |
09ad9bc7 | 174 | if (net_eq(ib_net(tb), net) && tb->port == snum) |
3f421baa ACM |
175 | goto tb_found; |
176 | } | |
177 | tb = NULL; | |
178 | goto tb_not_found; | |
179 | tb_found: | |
180 | if (!hlist_empty(&tb->owners)) { | |
4a17fd52 PE |
181 | if (sk->sk_reuse == SK_FORCE_REUSE) |
182 | goto success; | |
183 | ||
da5e3630 TH |
184 | if (((tb->fastreuse > 0 && |
185 | sk->sk_reuse && sk->sk_state != TCP_LISTEN) || | |
186 | (tb->fastreuseport > 0 && | |
187 | sk->sk_reuseport && uid_eq(tb->fastuid, uid))) && | |
a9d8f911 | 188 | smallest_size == -1) { |
3f421baa ACM |
189 | goto success; |
190 | } else { | |
191 | ret = 1; | |
aacd9289 | 192 | if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, true)) { |
da5e3630 | 193 | if (((sk->sk_reuse && sk->sk_state != TCP_LISTEN) || |
9c5e0c0b TH |
194 | (tb->fastreuseport > 0 && |
195 | sk->sk_reuseport && uid_eq(tb->fastuid, uid))) && | |
5add3009 | 196 | smallest_size != -1 && --attempts >= 0) { |
a9d8f911 EP |
197 | spin_unlock(&head->lock); |
198 | goto again; | |
199 | } | |
aacd9289 | 200 | |
3f421baa | 201 | goto fail_unlock; |
a9d8f911 | 202 | } |
3f421baa ACM |
203 | } |
204 | } | |
205 | tb_not_found: | |
206 | ret = 1; | |
941b1d22 PE |
207 | if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep, |
208 | net, head, snum)) == NULL) | |
3f421baa ACM |
209 | goto fail_unlock; |
210 | if (hlist_empty(&tb->owners)) { | |
211 | if (sk->sk_reuse && sk->sk_state != TCP_LISTEN) | |
212 | tb->fastreuse = 1; | |
213 | else | |
214 | tb->fastreuse = 0; | |
da5e3630 TH |
215 | if (sk->sk_reuseport) { |
216 | tb->fastreuseport = 1; | |
217 | tb->fastuid = uid; | |
9c5e0c0b | 218 | } else |
da5e3630 | 219 | tb->fastreuseport = 0; |
da5e3630 TH |
220 | } else { |
221 | if (tb->fastreuse && | |
222 | (!sk->sk_reuse || sk->sk_state == TCP_LISTEN)) | |
223 | tb->fastreuse = 0; | |
224 | if (tb->fastreuseport && | |
9c5e0c0b | 225 | (!sk->sk_reuseport || !uid_eq(tb->fastuid, uid))) |
da5e3630 | 226 | tb->fastreuseport = 0; |
da5e3630 | 227 | } |
3f421baa ACM |
228 | success: |
229 | if (!inet_csk(sk)->icsk_bind_hash) | |
230 | inet_bind_hash(sk, tb, snum); | |
547b792c | 231 | WARN_ON(inet_csk(sk)->icsk_bind_hash != tb); |
e905a9ed | 232 | ret = 0; |
3f421baa ACM |
233 | |
234 | fail_unlock: | |
235 | spin_unlock(&head->lock); | |
236 | fail: | |
237 | local_bh_enable(); | |
238 | return ret; | |
239 | } | |
3f421baa ACM |
240 | EXPORT_SYMBOL_GPL(inet_csk_get_port); |
241 | ||
242 | /* | |
243 | * Wait for an incoming connection, avoid race conditions. This must be called | |
244 | * with the socket locked. | |
245 | */ | |
246 | static int inet_csk_wait_for_connect(struct sock *sk, long timeo) | |
247 | { | |
248 | struct inet_connection_sock *icsk = inet_csk(sk); | |
249 | DEFINE_WAIT(wait); | |
250 | int err; | |
251 | ||
252 | /* | |
253 | * True wake-one mechanism for incoming connections: only | |
254 | * one process gets woken up, not the 'whole herd'. | |
255 | * Since we do not 'race & poll' for established sockets | |
256 | * anymore, the common case will execute the loop only once. | |
257 | * | |
258 | * Subtle issue: "add_wait_queue_exclusive()" will be added | |
259 | * after any current non-exclusive waiters, and we know that | |
260 | * it will always _stay_ after any new non-exclusive waiters | |
261 | * because all non-exclusive waiters are added at the | |
262 | * beginning of the wait-queue. As such, it's ok to "drop" | |
263 | * our exclusiveness temporarily when we get woken up without | |
264 | * having to remove and re-insert us on the wait queue. | |
265 | */ | |
266 | for (;;) { | |
aa395145 | 267 | prepare_to_wait_exclusive(sk_sleep(sk), &wait, |
3f421baa ACM |
268 | TASK_INTERRUPTIBLE); |
269 | release_sock(sk); | |
270 | if (reqsk_queue_empty(&icsk->icsk_accept_queue)) | |
271 | timeo = schedule_timeout(timeo); | |
272 | lock_sock(sk); | |
273 | err = 0; | |
274 | if (!reqsk_queue_empty(&icsk->icsk_accept_queue)) | |
275 | break; | |
276 | err = -EINVAL; | |
277 | if (sk->sk_state != TCP_LISTEN) | |
278 | break; | |
279 | err = sock_intr_errno(timeo); | |
280 | if (signal_pending(current)) | |
281 | break; | |
282 | err = -EAGAIN; | |
283 | if (!timeo) | |
284 | break; | |
285 | } | |
aa395145 | 286 | finish_wait(sk_sleep(sk), &wait); |
3f421baa ACM |
287 | return err; |
288 | } | |
289 | ||
290 | /* | |
291 | * This will accept the next outstanding connection. | |
292 | */ | |
293 | struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) | |
294 | { | |
295 | struct inet_connection_sock *icsk = inet_csk(sk); | |
8336886f | 296 | struct request_sock_queue *queue = &icsk->icsk_accept_queue; |
8336886f | 297 | struct request_sock *req; |
e3d95ad7 | 298 | struct sock *newsk; |
3f421baa ACM |
299 | int error; |
300 | ||
301 | lock_sock(sk); | |
302 | ||
303 | /* We need to make sure that this socket is listening, | |
304 | * and that it has something pending. | |
305 | */ | |
306 | error = -EINVAL; | |
307 | if (sk->sk_state != TCP_LISTEN) | |
308 | goto out_err; | |
309 | ||
310 | /* Find already established connection */ | |
8336886f | 311 | if (reqsk_queue_empty(queue)) { |
3f421baa ACM |
312 | long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); |
313 | ||
314 | /* If this is a non blocking socket don't sleep */ | |
315 | error = -EAGAIN; | |
316 | if (!timeo) | |
317 | goto out_err; | |
318 | ||
319 | error = inet_csk_wait_for_connect(sk, timeo); | |
320 | if (error) | |
321 | goto out_err; | |
322 | } | |
8336886f JC |
323 | req = reqsk_queue_remove(queue); |
324 | newsk = req->sk; | |
325 | ||
326 | sk_acceptq_removed(sk); | |
e3d95ad7 ED |
327 | if (sk->sk_protocol == IPPROTO_TCP && |
328 | tcp_rsk(req)->tfo_listener && | |
329 | queue->fastopenq) { | |
8336886f | 330 | spin_lock_bh(&queue->fastopenq->lock); |
9439ce00 | 331 | if (tcp_rsk(req)->tfo_listener) { |
8336886f JC |
332 | /* We are still waiting for the final ACK from 3WHS |
333 | * so can't free req now. Instead, we set req->sk to | |
334 | * NULL to signify that the child socket is taken | |
335 | * so reqsk_fastopen_remove() will free the req | |
336 | * when 3WHS finishes (or is aborted). | |
337 | */ | |
338 | req->sk = NULL; | |
339 | req = NULL; | |
340 | } | |
341 | spin_unlock_bh(&queue->fastopenq->lock); | |
342 | } | |
3f421baa ACM |
343 | out: |
344 | release_sock(sk); | |
8336886f | 345 | if (req) |
13854e5a | 346 | reqsk_put(req); |
3f421baa ACM |
347 | return newsk; |
348 | out_err: | |
349 | newsk = NULL; | |
8336886f | 350 | req = NULL; |
3f421baa ACM |
351 | *err = error; |
352 | goto out; | |
353 | } | |
3f421baa ACM |
354 | EXPORT_SYMBOL(inet_csk_accept); |
355 | ||
356 | /* | |
357 | * Using different timers for retransmit, delayed acks and probes | |
e905a9ed | 358 | * We may wish use just one timer maintaining a list of expire jiffies |
3f421baa ACM |
359 | * to optimize. |
360 | */ | |
361 | void inet_csk_init_xmit_timers(struct sock *sk, | |
362 | void (*retransmit_handler)(unsigned long), | |
363 | void (*delack_handler)(unsigned long), | |
364 | void (*keepalive_handler)(unsigned long)) | |
365 | { | |
366 | struct inet_connection_sock *icsk = inet_csk(sk); | |
367 | ||
b24b8a24 PE |
368 | setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler, |
369 | (unsigned long)sk); | |
370 | setup_timer(&icsk->icsk_delack_timer, delack_handler, | |
371 | (unsigned long)sk); | |
372 | setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk); | |
3f421baa ACM |
373 | icsk->icsk_pending = icsk->icsk_ack.pending = 0; |
374 | } | |
3f421baa ACM |
375 | EXPORT_SYMBOL(inet_csk_init_xmit_timers); |
376 | ||
377 | void inet_csk_clear_xmit_timers(struct sock *sk) | |
378 | { | |
379 | struct inet_connection_sock *icsk = inet_csk(sk); | |
380 | ||
381 | icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0; | |
382 | ||
383 | sk_stop_timer(sk, &icsk->icsk_retransmit_timer); | |
384 | sk_stop_timer(sk, &icsk->icsk_delack_timer); | |
385 | sk_stop_timer(sk, &sk->sk_timer); | |
386 | } | |
3f421baa ACM |
387 | EXPORT_SYMBOL(inet_csk_clear_xmit_timers); |
388 | ||
389 | void inet_csk_delete_keepalive_timer(struct sock *sk) | |
390 | { | |
391 | sk_stop_timer(sk, &sk->sk_timer); | |
392 | } | |
3f421baa ACM |
393 | EXPORT_SYMBOL(inet_csk_delete_keepalive_timer); |
394 | ||
395 | void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len) | |
396 | { | |
397 | sk_reset_timer(sk, &sk->sk_timer, jiffies + len); | |
398 | } | |
3f421baa ACM |
399 | EXPORT_SYMBOL(inet_csk_reset_keepalive_timer); |
400 | ||
d9319100 | 401 | struct dst_entry *inet_csk_route_req(struct sock *sk, |
6bd023f3 | 402 | struct flowi4 *fl4, |
ba3f7f04 | 403 | const struct request_sock *req) |
3f421baa ACM |
404 | { |
405 | struct rtable *rt; | |
406 | const struct inet_request_sock *ireq = inet_rsk(req); | |
f6d8bd05 | 407 | struct ip_options_rcu *opt = inet_rsk(req)->opt; |
84a3aa00 | 408 | struct net *net = sock_net(sk); |
3e12939a | 409 | int flags = inet_sk_flowi_flags(sk); |
3f421baa | 410 | |
84f39b08 | 411 | flowi4_init_output(fl4, sk->sk_bound_dev_if, ireq->ir_mark, |
e79d9bc7 | 412 | RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, |
7433819a | 413 | sk->sk_protocol, |
7586eceb | 414 | flags, |
634fb979 ED |
415 | (opt && opt->opt.srr) ? opt->opt.faddr : ireq->ir_rmt_addr, |
416 | ireq->ir_loc_addr, ireq->ir_rmt_port, inet_sk(sk)->inet_sport); | |
6bd023f3 DM |
417 | security_req_classify_flow(req, flowi4_to_flowi(fl4)); |
418 | rt = ip_route_output_flow(net, fl4, sk); | |
b23dd4fe | 419 | if (IS_ERR(rt)) |
857a6e0a | 420 | goto no_route; |
155e8336 | 421 | if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway) |
857a6e0a | 422 | goto route_err; |
d8d1f30b | 423 | return &rt->dst; |
857a6e0a IJ |
424 | |
425 | route_err: | |
426 | ip_rt_put(rt); | |
427 | no_route: | |
428 | IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); | |
429 | return NULL; | |
3f421baa | 430 | } |
3f421baa ACM |
431 | EXPORT_SYMBOL_GPL(inet_csk_route_req); |
432 | ||
77357a95 DM |
433 | struct dst_entry *inet_csk_route_child_sock(struct sock *sk, |
434 | struct sock *newsk, | |
435 | const struct request_sock *req) | |
436 | { | |
437 | const struct inet_request_sock *ireq = inet_rsk(req); | |
438 | struct inet_sock *newinet = inet_sk(newsk); | |
1a7b27c9 | 439 | struct ip_options_rcu *opt; |
77357a95 DM |
440 | struct net *net = sock_net(sk); |
441 | struct flowi4 *fl4; | |
442 | struct rtable *rt; | |
443 | ||
444 | fl4 = &newinet->cork.fl.u.ip4; | |
1a7b27c9 CP |
445 | |
446 | rcu_read_lock(); | |
447 | opt = rcu_dereference(newinet->inet_opt); | |
84f39b08 | 448 | flowi4_init_output(fl4, sk->sk_bound_dev_if, inet_rsk(req)->ir_mark, |
77357a95 DM |
449 | RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, |
450 | sk->sk_protocol, inet_sk_flowi_flags(sk), | |
634fb979 ED |
451 | (opt && opt->opt.srr) ? opt->opt.faddr : ireq->ir_rmt_addr, |
452 | ireq->ir_loc_addr, ireq->ir_rmt_port, inet_sk(sk)->inet_sport); | |
77357a95 DM |
453 | security_req_classify_flow(req, flowi4_to_flowi(fl4)); |
454 | rt = ip_route_output_flow(net, fl4, sk); | |
455 | if (IS_ERR(rt)) | |
456 | goto no_route; | |
155e8336 | 457 | if (opt && opt->opt.is_strictroute && rt->rt_uses_gateway) |
77357a95 | 458 | goto route_err; |
1a7b27c9 | 459 | rcu_read_unlock(); |
77357a95 DM |
460 | return &rt->dst; |
461 | ||
462 | route_err: | |
463 | ip_rt_put(rt); | |
464 | no_route: | |
1a7b27c9 | 465 | rcu_read_unlock(); |
77357a95 DM |
466 | IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); |
467 | return NULL; | |
468 | } | |
469 | EXPORT_SYMBOL_GPL(inet_csk_route_child_sock); | |
470 | ||
6b72977b | 471 | static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport, |
72a3effa | 472 | const u32 rnd, const u32 synq_hsize) |
3f421baa | 473 | { |
6b72977b | 474 | return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1); |
3f421baa ACM |
475 | } |
476 | ||
dfd56b8b | 477 | #if IS_ENABLED(CONFIG_IPV6) |
3f421baa ACM |
478 | #define AF_INET_FAMILY(fam) ((fam) == AF_INET) |
479 | #else | |
fa76ce73 | 480 | #define AF_INET_FAMILY(fam) true |
3f421baa ACM |
481 | #endif |
482 | ||
fa76ce73 ED |
483 | /* Note: this is temporary : |
484 | * req sock will no longer be in listener hash table | |
485 | */ | |
486 | struct request_sock *inet_csk_search_req(struct sock *sk, | |
487 | const __be16 rport, | |
488 | const __be32 raddr, | |
7f25afbb | 489 | const __be32 laddr) |
3f421baa | 490 | { |
fa76ce73 | 491 | struct inet_connection_sock *icsk = inet_csk(sk); |
3f421baa | 492 | struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; |
52452c54 | 493 | struct request_sock *req; |
fa76ce73 ED |
494 | u32 hash = inet_synq_hash(raddr, rport, lopt->hash_rnd, |
495 | lopt->nr_table_entries); | |
3f421baa | 496 | |
fa76ce73 ED |
497 | write_lock(&icsk->icsk_accept_queue.syn_wait_lock); |
498 | for (req = lopt->syn_table[hash]; req != NULL; req = req->dl_next) { | |
3f421baa ACM |
499 | const struct inet_request_sock *ireq = inet_rsk(req); |
500 | ||
634fb979 ED |
501 | if (ireq->ir_rmt_port == rport && |
502 | ireq->ir_rmt_addr == raddr && | |
503 | ireq->ir_loc_addr == laddr && | |
3f421baa | 504 | AF_INET_FAMILY(req->rsk_ops->family)) { |
fa76ce73 | 505 | atomic_inc(&req->rsk_refcnt); |
547b792c | 506 | WARN_ON(req->sk); |
3f421baa ACM |
507 | break; |
508 | } | |
509 | } | |
fa76ce73 | 510 | write_unlock(&icsk->icsk_accept_queue.syn_wait_lock); |
3f421baa ACM |
511 | |
512 | return req; | |
513 | } | |
3f421baa ACM |
514 | EXPORT_SYMBOL_GPL(inet_csk_search_req); |
515 | ||
516 | void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, | |
c2977c22 | 517 | unsigned long timeout) |
3f421baa ACM |
518 | { |
519 | struct inet_connection_sock *icsk = inet_csk(sk); | |
520 | struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; | |
634fb979 ED |
521 | const u32 h = inet_synq_hash(inet_rsk(req)->ir_rmt_addr, |
522 | inet_rsk(req)->ir_rmt_port, | |
3f421baa ACM |
523 | lopt->hash_rnd, lopt->nr_table_entries); |
524 | ||
525 | reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout); | |
526 | inet_csk_reqsk_queue_added(sk, timeout); | |
527 | } | |
4bc2f18b | 528 | EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add); |
3f421baa | 529 | |
a019d6fe ACM |
530 | /* Only thing we need from tcp.h */ |
531 | extern int sysctl_tcp_synack_retries; | |
532 | ||
9f1d2604 | 533 | |
0c3d79bc JA |
534 | /* Decide when to expire the request and when to resend SYN-ACK */ |
535 | static inline void syn_ack_recalc(struct request_sock *req, const int thresh, | |
536 | const int max_retries, | |
537 | const u8 rskq_defer_accept, | |
538 | int *expire, int *resend) | |
539 | { | |
540 | if (!rskq_defer_accept) { | |
e6c022a4 | 541 | *expire = req->num_timeout >= thresh; |
0c3d79bc JA |
542 | *resend = 1; |
543 | return; | |
544 | } | |
e6c022a4 ED |
545 | *expire = req->num_timeout >= thresh && |
546 | (!inet_rsk(req)->acked || req->num_timeout >= max_retries); | |
0c3d79bc JA |
547 | /* |
548 | * Do not resend while waiting for data after ACK, | |
549 | * start to resend on end of deferring period to give | |
550 | * last chance for data or ACK to create established socket. | |
551 | */ | |
552 | *resend = !inet_rsk(req)->acked || | |
e6c022a4 | 553 | req->num_timeout >= rskq_defer_accept - 1; |
0c3d79bc JA |
554 | } |
555 | ||
e6c022a4 ED |
556 | int inet_rtx_syn_ack(struct sock *parent, struct request_sock *req) |
557 | { | |
1a2c6181 | 558 | int err = req->rsk_ops->rtx_syn_ack(parent, req); |
e6c022a4 ED |
559 | |
560 | if (!err) | |
561 | req->num_retrans++; | |
562 | return err; | |
563 | } | |
564 | EXPORT_SYMBOL(inet_rtx_syn_ack); | |
565 | ||
fa76ce73 | 566 | static void reqsk_timer_handler(unsigned long data) |
a019d6fe | 567 | { |
fa76ce73 ED |
568 | struct request_sock *req = (struct request_sock *)data; |
569 | struct sock *sk_listener = req->rsk_listener; | |
570 | struct inet_connection_sock *icsk = inet_csk(sk_listener); | |
a019d6fe ACM |
571 | struct request_sock_queue *queue = &icsk->icsk_accept_queue; |
572 | struct listen_sock *lopt = queue->listen_opt; | |
fa76ce73 ED |
573 | int expire = 0, resend = 0; |
574 | int max_retries, thresh; | |
a019d6fe | 575 | |
fa76ce73 ED |
576 | if (sk_listener->sk_state != TCP_LISTEN || !lopt) { |
577 | reqsk_put(req); | |
a019d6fe | 578 | return; |
fa76ce73 | 579 | } |
a019d6fe | 580 | |
fa76ce73 ED |
581 | max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries; |
582 | thresh = max_retries; | |
a019d6fe ACM |
583 | /* Normally all the openreqs are young and become mature |
584 | * (i.e. converted to established socket) for first timeout. | |
fd4f2cea | 585 | * If synack was not acknowledged for 1 second, it means |
a019d6fe ACM |
586 | * one of the following things: synack was lost, ack was lost, |
587 | * rtt is high or nobody planned to ack (i.e. synflood). | |
588 | * When server is a bit loaded, queue is populated with old | |
589 | * open requests, reducing effective size of queue. | |
590 | * When server is well loaded, queue size reduces to zero | |
591 | * after several minutes of work. It is not synflood, | |
592 | * it is normal operation. The solution is pruning | |
593 | * too old entries overriding normal timeout, when | |
594 | * situation becomes dangerous. | |
595 | * | |
596 | * Essentially, we reserve half of room for young | |
597 | * embrions; and abort old ones without pity, if old | |
598 | * ones are about to clog our table. | |
599 | */ | |
fa76ce73 ED |
600 | if (listen_sock_qlen(lopt) >> (lopt->max_qlen_log - 1)) { |
601 | int young = listen_sock_young(lopt) << 1; | |
a019d6fe ACM |
602 | |
603 | while (thresh > 2) { | |
fa76ce73 | 604 | if (listen_sock_qlen(lopt) < young) |
a019d6fe ACM |
605 | break; |
606 | thresh--; | |
607 | young <<= 1; | |
608 | } | |
609 | } | |
ec0a1966 DM |
610 | if (queue->rskq_defer_accept) |
611 | max_retries = queue->rskq_defer_accept; | |
fa76ce73 ED |
612 | syn_ack_recalc(req, thresh, max_retries, queue->rskq_defer_accept, |
613 | &expire, &resend); | |
614 | req->rsk_ops->syn_ack_timeout(sk_listener, req); | |
615 | if (!expire && | |
616 | (!resend || | |
617 | !inet_rtx_syn_ack(sk_listener, req) || | |
618 | inet_rsk(req)->acked)) { | |
619 | unsigned long timeo; | |
620 | ||
621 | if (req->num_timeout++ == 0) | |
622 | atomic_inc(&lopt->young_dec); | |
623 | timeo = min(TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX); | |
624 | mod_timer_pinned(&req->rsk_timer, jiffies + timeo); | |
625 | return; | |
626 | } | |
627 | inet_csk_reqsk_queue_drop(sk_listener, req); | |
628 | reqsk_put(req); | |
629 | } | |
ec0a1966 | 630 | |
fa76ce73 ED |
631 | void reqsk_queue_hash_req(struct request_sock_queue *queue, |
632 | u32 hash, struct request_sock *req, | |
633 | unsigned long timeout) | |
634 | { | |
635 | struct listen_sock *lopt = queue->listen_opt; | |
a019d6fe | 636 | |
fa76ce73 ED |
637 | req->num_retrans = 0; |
638 | req->num_timeout = 0; | |
639 | req->sk = NULL; | |
a019d6fe | 640 | |
fa76ce73 ED |
641 | /* before letting lookups find us, make sure all req fields |
642 | * are committed to memory and refcnt initialized. | |
643 | */ | |
644 | smp_wmb(); | |
645 | atomic_set(&req->rsk_refcnt, 2); | |
646 | setup_timer(&req->rsk_timer, reqsk_timer_handler, (unsigned long)req); | |
647 | req->rsk_hash = hash; | |
a019d6fe | 648 | |
fa76ce73 ED |
649 | write_lock(&queue->syn_wait_lock); |
650 | req->dl_next = lopt->syn_table[hash]; | |
651 | lopt->syn_table[hash] = req; | |
652 | write_unlock(&queue->syn_wait_lock); | |
a019d6fe | 653 | |
fa76ce73 | 654 | mod_timer_pinned(&req->rsk_timer, jiffies + timeout); |
a019d6fe | 655 | } |
fa76ce73 | 656 | EXPORT_SYMBOL(reqsk_queue_hash_req); |
a019d6fe | 657 | |
e56c57d0 ED |
658 | /** |
659 | * inet_csk_clone_lock - clone an inet socket, and lock its clone | |
660 | * @sk: the socket to clone | |
661 | * @req: request_sock | |
662 | * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) | |
663 | * | |
664 | * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) | |
665 | */ | |
666 | struct sock *inet_csk_clone_lock(const struct sock *sk, | |
667 | const struct request_sock *req, | |
668 | const gfp_t priority) | |
9f1d2604 | 669 | { |
e56c57d0 | 670 | struct sock *newsk = sk_clone_lock(sk, priority); |
9f1d2604 ACM |
671 | |
672 | if (newsk != NULL) { | |
673 | struct inet_connection_sock *newicsk = inet_csk(newsk); | |
674 | ||
675 | newsk->sk_state = TCP_SYN_RECV; | |
676 | newicsk->icsk_bind_hash = NULL; | |
677 | ||
634fb979 | 678 | inet_sk(newsk)->inet_dport = inet_rsk(req)->ir_rmt_port; |
b44084c2 ED |
679 | inet_sk(newsk)->inet_num = inet_rsk(req)->ir_num; |
680 | inet_sk(newsk)->inet_sport = htons(inet_rsk(req)->ir_num); | |
9f1d2604 ACM |
681 | newsk->sk_write_space = sk_stream_write_space; |
682 | ||
84f39b08 | 683 | newsk->sk_mark = inet_rsk(req)->ir_mark; |
33cf7c90 ED |
684 | atomic64_set(&newsk->sk_cookie, |
685 | atomic64_read(&inet_rsk(req)->ir_cookie)); | |
84f39b08 | 686 | |
9f1d2604 | 687 | newicsk->icsk_retransmits = 0; |
6687e988 ACM |
688 | newicsk->icsk_backoff = 0; |
689 | newicsk->icsk_probes_out = 0; | |
9f1d2604 ACM |
690 | |
691 | /* Deinitialize accept_queue to trap illegal accesses. */ | |
692 | memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue)); | |
4237c75c VY |
693 | |
694 | security_inet_csk_clone(newsk, req); | |
9f1d2604 ACM |
695 | } |
696 | return newsk; | |
697 | } | |
e56c57d0 | 698 | EXPORT_SYMBOL_GPL(inet_csk_clone_lock); |
a019d6fe ACM |
699 | |
700 | /* | |
701 | * At this point, there should be no process reference to this | |
702 | * socket, and thus no user references at all. Therefore we | |
703 | * can assume the socket waitqueue is inactive and nobody will | |
704 | * try to jump onto it. | |
705 | */ | |
706 | void inet_csk_destroy_sock(struct sock *sk) | |
707 | { | |
547b792c IJ |
708 | WARN_ON(sk->sk_state != TCP_CLOSE); |
709 | WARN_ON(!sock_flag(sk, SOCK_DEAD)); | |
a019d6fe ACM |
710 | |
711 | /* It cannot be in hash table! */ | |
547b792c | 712 | WARN_ON(!sk_unhashed(sk)); |
a019d6fe | 713 | |
c720c7e8 ED |
714 | /* If it has not 0 inet_sk(sk)->inet_num, it must be bound */ |
715 | WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash); | |
a019d6fe ACM |
716 | |
717 | sk->sk_prot->destroy(sk); | |
718 | ||
719 | sk_stream_kill_queues(sk); | |
720 | ||
721 | xfrm_sk_free_policy(sk); | |
722 | ||
723 | sk_refcnt_debug_release(sk); | |
724 | ||
dd24c001 | 725 | percpu_counter_dec(sk->sk_prot->orphan_count); |
a019d6fe ACM |
726 | sock_put(sk); |
727 | } | |
a019d6fe ACM |
728 | EXPORT_SYMBOL(inet_csk_destroy_sock); |
729 | ||
e337e24d CP |
730 | /* This function allows to force a closure of a socket after the call to |
731 | * tcp/dccp_create_openreq_child(). | |
732 | */ | |
733 | void inet_csk_prepare_forced_close(struct sock *sk) | |
c10cb5fc | 734 | __releases(&sk->sk_lock.slock) |
e337e24d CP |
735 | { |
736 | /* sk_clone_lock locked the socket and set refcnt to 2 */ | |
737 | bh_unlock_sock(sk); | |
738 | sock_put(sk); | |
739 | ||
740 | /* The below has to be done to allow calling inet_csk_destroy_sock */ | |
741 | sock_set_flag(sk, SOCK_DEAD); | |
742 | percpu_counter_inc(sk->sk_prot->orphan_count); | |
743 | inet_sk(sk)->inet_num = 0; | |
744 | } | |
745 | EXPORT_SYMBOL(inet_csk_prepare_forced_close); | |
746 | ||
a019d6fe ACM |
747 | int inet_csk_listen_start(struct sock *sk, const int nr_table_entries) |
748 | { | |
749 | struct inet_sock *inet = inet_sk(sk); | |
750 | struct inet_connection_sock *icsk = inet_csk(sk); | |
751 | int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries); | |
752 | ||
753 | if (rc != 0) | |
754 | return rc; | |
755 | ||
756 | sk->sk_max_ack_backlog = 0; | |
757 | sk->sk_ack_backlog = 0; | |
758 | inet_csk_delack_init(sk); | |
759 | ||
760 | /* There is race window here: we announce ourselves listening, | |
761 | * but this transition is still not validated by get_port(). | |
762 | * It is OK, because this socket enters to hash table only | |
763 | * after validation is complete. | |
764 | */ | |
765 | sk->sk_state = TCP_LISTEN; | |
c720c7e8 ED |
766 | if (!sk->sk_prot->get_port(sk, inet->inet_num)) { |
767 | inet->inet_sport = htons(inet->inet_num); | |
a019d6fe ACM |
768 | |
769 | sk_dst_reset(sk); | |
770 | sk->sk_prot->hash(sk); | |
771 | ||
772 | return 0; | |
773 | } | |
774 | ||
775 | sk->sk_state = TCP_CLOSE; | |
776 | __reqsk_queue_destroy(&icsk->icsk_accept_queue); | |
777 | return -EADDRINUSE; | |
778 | } | |
a019d6fe ACM |
779 | EXPORT_SYMBOL_GPL(inet_csk_listen_start); |
780 | ||
781 | /* | |
782 | * This routine closes sockets which have been at least partially | |
783 | * opened, but not yet accepted. | |
784 | */ | |
785 | void inet_csk_listen_stop(struct sock *sk) | |
786 | { | |
787 | struct inet_connection_sock *icsk = inet_csk(sk); | |
8336886f | 788 | struct request_sock_queue *queue = &icsk->icsk_accept_queue; |
a019d6fe ACM |
789 | struct request_sock *acc_req; |
790 | struct request_sock *req; | |
791 | ||
a019d6fe | 792 | /* make all the listen_opt local to us */ |
8336886f | 793 | acc_req = reqsk_queue_yank_acceptq(queue); |
a019d6fe ACM |
794 | |
795 | /* Following specs, it would be better either to send FIN | |
796 | * (and enter FIN-WAIT-1, it is normal close) | |
797 | * or to send active reset (abort). | |
798 | * Certainly, it is pretty dangerous while synflood, but it is | |
799 | * bad justification for our negligence 8) | |
800 | * To be honest, we are not able to make either | |
801 | * of the variants now. --ANK | |
802 | */ | |
8336886f | 803 | reqsk_queue_destroy(queue); |
a019d6fe ACM |
804 | |
805 | while ((req = acc_req) != NULL) { | |
806 | struct sock *child = req->sk; | |
807 | ||
808 | acc_req = req->dl_next; | |
809 | ||
810 | local_bh_disable(); | |
811 | bh_lock_sock(child); | |
547b792c | 812 | WARN_ON(sock_owned_by_user(child)); |
a019d6fe ACM |
813 | sock_hold(child); |
814 | ||
815 | sk->sk_prot->disconnect(child, O_NONBLOCK); | |
816 | ||
817 | sock_orphan(child); | |
818 | ||
eb4dea58 HX |
819 | percpu_counter_inc(sk->sk_prot->orphan_count); |
820 | ||
9439ce00 | 821 | if (sk->sk_protocol == IPPROTO_TCP && tcp_rsk(req)->tfo_listener) { |
8336886f | 822 | BUG_ON(tcp_sk(child)->fastopen_rsk != req); |
9439ce00 | 823 | BUG_ON(sk != req->rsk_listener); |
8336886f JC |
824 | |
825 | /* Paranoid, to prevent race condition if | |
826 | * an inbound pkt destined for child is | |
827 | * blocked by sock lock in tcp_v4_rcv(). | |
828 | * Also to satisfy an assertion in | |
829 | * tcp_v4_destroy_sock(). | |
830 | */ | |
831 | tcp_sk(child)->fastopen_rsk = NULL; | |
8336886f | 832 | } |
a019d6fe ACM |
833 | inet_csk_destroy_sock(child); |
834 | ||
835 | bh_unlock_sock(child); | |
836 | local_bh_enable(); | |
837 | sock_put(child); | |
838 | ||
839 | sk_acceptq_removed(sk); | |
13854e5a | 840 | reqsk_put(req); |
a019d6fe | 841 | } |
8336886f JC |
842 | if (queue->fastopenq != NULL) { |
843 | /* Free all the reqs queued in rskq_rst_head. */ | |
844 | spin_lock_bh(&queue->fastopenq->lock); | |
845 | acc_req = queue->fastopenq->rskq_rst_head; | |
846 | queue->fastopenq->rskq_rst_head = NULL; | |
847 | spin_unlock_bh(&queue->fastopenq->lock); | |
848 | while ((req = acc_req) != NULL) { | |
849 | acc_req = req->dl_next; | |
13854e5a | 850 | reqsk_put(req); |
8336886f JC |
851 | } |
852 | } | |
547b792c | 853 | WARN_ON(sk->sk_ack_backlog); |
a019d6fe | 854 | } |
a019d6fe | 855 | EXPORT_SYMBOL_GPL(inet_csk_listen_stop); |
af05dc93 ACM |
856 | |
857 | void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) | |
858 | { | |
859 | struct sockaddr_in *sin = (struct sockaddr_in *)uaddr; | |
860 | const struct inet_sock *inet = inet_sk(sk); | |
861 | ||
862 | sin->sin_family = AF_INET; | |
c720c7e8 ED |
863 | sin->sin_addr.s_addr = inet->inet_daddr; |
864 | sin->sin_port = inet->inet_dport; | |
af05dc93 | 865 | } |
af05dc93 | 866 | EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr); |
c4d93909 | 867 | |
dec73ff0 ACM |
868 | #ifdef CONFIG_COMPAT |
869 | int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, | |
870 | char __user *optval, int __user *optlen) | |
871 | { | |
dbeff12b | 872 | const struct inet_connection_sock *icsk = inet_csk(sk); |
dec73ff0 ACM |
873 | |
874 | if (icsk->icsk_af_ops->compat_getsockopt != NULL) | |
875 | return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname, | |
876 | optval, optlen); | |
877 | return icsk->icsk_af_ops->getsockopt(sk, level, optname, | |
878 | optval, optlen); | |
879 | } | |
dec73ff0 ACM |
880 | EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt); |
881 | ||
882 | int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, | |
b7058842 | 883 | char __user *optval, unsigned int optlen) |
dec73ff0 | 884 | { |
dbeff12b | 885 | const struct inet_connection_sock *icsk = inet_csk(sk); |
dec73ff0 ACM |
886 | |
887 | if (icsk->icsk_af_ops->compat_setsockopt != NULL) | |
888 | return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname, | |
889 | optval, optlen); | |
890 | return icsk->icsk_af_ops->setsockopt(sk, level, optname, | |
891 | optval, optlen); | |
892 | } | |
dec73ff0 ACM |
893 | EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt); |
894 | #endif | |
80d0a69f DM |
895 | |
896 | static struct dst_entry *inet_csk_rebuild_route(struct sock *sk, struct flowi *fl) | |
897 | { | |
5abf7f7e ED |
898 | const struct inet_sock *inet = inet_sk(sk); |
899 | const struct ip_options_rcu *inet_opt; | |
80d0a69f DM |
900 | __be32 daddr = inet->inet_daddr; |
901 | struct flowi4 *fl4; | |
902 | struct rtable *rt; | |
903 | ||
904 | rcu_read_lock(); | |
905 | inet_opt = rcu_dereference(inet->inet_opt); | |
906 | if (inet_opt && inet_opt->opt.srr) | |
907 | daddr = inet_opt->opt.faddr; | |
908 | fl4 = &fl->u.ip4; | |
909 | rt = ip_route_output_ports(sock_net(sk), fl4, sk, daddr, | |
910 | inet->inet_saddr, inet->inet_dport, | |
911 | inet->inet_sport, sk->sk_protocol, | |
912 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if); | |
913 | if (IS_ERR(rt)) | |
914 | rt = NULL; | |
915 | if (rt) | |
916 | sk_setup_caps(sk, &rt->dst); | |
917 | rcu_read_unlock(); | |
918 | ||
919 | return &rt->dst; | |
920 | } | |
921 | ||
922 | struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu) | |
923 | { | |
924 | struct dst_entry *dst = __sk_dst_check(sk, 0); | |
925 | struct inet_sock *inet = inet_sk(sk); | |
926 | ||
927 | if (!dst) { | |
928 | dst = inet_csk_rebuild_route(sk, &inet->cork.fl); | |
929 | if (!dst) | |
930 | goto out; | |
931 | } | |
6700c270 | 932 | dst->ops->update_pmtu(dst, sk, NULL, mtu); |
80d0a69f DM |
933 | |
934 | dst = __sk_dst_check(sk, 0); | |
935 | if (!dst) | |
936 | dst = inet_csk_rebuild_route(sk, &inet->cork.fl); | |
937 | out: | |
938 | return dst; | |
939 | } | |
940 | EXPORT_SYMBOL_GPL(inet_csk_update_pmtu); |