inet_connection_sock.c revision 86b08d867d7de001ab224180ed7865fab93fd56e
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 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> 25#include <net/xfrm.h> 26 27#ifdef INET_CSK_DEBUG 28const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n"; 29EXPORT_SYMBOL(inet_csk_timer_bug_msg); 30#endif 31 32/* 33 * This array holds the first and last local port number. 34 */ 35int sysctl_local_port_range[2] = { 32768, 61000 }; 36DEFINE_SEQLOCK(sysctl_port_range_lock); 37 38void inet_get_local_port_range(int *low, int *high) 39{ 40 unsigned seq; 41 do { 42 seq = read_seqbegin(&sysctl_port_range_lock); 43 44 *low = sysctl_local_port_range[0]; 45 *high = sysctl_local_port_range[1]; 46 } while (read_seqretry(&sysctl_port_range_lock, seq)); 47} 48EXPORT_SYMBOL(inet_get_local_port_range); 49 50int inet_csk_bind_conflict(const struct sock *sk, 51 const struct inet_bind_bucket *tb) 52{ 53 const __be32 sk_rcv_saddr = inet_rcv_saddr(sk); 54 struct sock *sk2; 55 struct hlist_node *node; 56 int reuse = sk->sk_reuse; 57 58 /* 59 * Unlike other sk lookup places we do not check 60 * for sk_net here, since _all_ the socks listed 61 * in tb->owners list belong to the same net - the 62 * one this bucket belongs to. 63 */ 64 65 sk_for_each_bound(sk2, node, &tb->owners) { 66 if (sk != sk2 && 67 !inet_v6_ipv6only(sk2) && 68 (!sk->sk_bound_dev_if || 69 !sk2->sk_bound_dev_if || 70 sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) { 71 if (!reuse || !sk2->sk_reuse || 72 sk2->sk_state == TCP_LISTEN) { 73 const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2); 74 if (!sk2_rcv_saddr || !sk_rcv_saddr || 75 sk2_rcv_saddr == sk_rcv_saddr) 76 break; 77 } 78 } 79 } 80 return node != NULL; 81} 82 83EXPORT_SYMBOL_GPL(inet_csk_bind_conflict); 84 85/* Obtain a reference to a local port for the given sock, 86 * if snum is zero it means select any available local port. 87 */ 88int inet_csk_get_port(struct sock *sk, unsigned short snum) 89{ 90 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo; 91 struct inet_bind_hashbucket *head; 92 struct hlist_node *node; 93 struct inet_bind_bucket *tb; 94 int ret; 95 struct net *net = sock_net(sk); 96 97 local_bh_disable(); 98 if (!snum) { 99 int remaining, rover, low, high; 100 101 inet_get_local_port_range(&low, &high); 102 remaining = (high - low) + 1; 103 rover = net_random() % remaining + low; 104 105 do { 106 head = &hashinfo->bhash[inet_bhashfn(net, rover, 107 hashinfo->bhash_size)]; 108 spin_lock(&head->lock); 109 inet_bind_bucket_for_each(tb, node, &head->chain) 110 if (tb->ib_net == net && tb->port == rover) 111 goto next; 112 break; 113 next: 114 spin_unlock(&head->lock); 115 if (++rover > high) 116 rover = low; 117 } while (--remaining > 0); 118 119 /* Exhausted local port range during search? It is not 120 * possible for us to be holding one of the bind hash 121 * locks if this test triggers, because if 'remaining' 122 * drops to zero, we broke out of the do/while loop at 123 * the top level, not from the 'break;' statement. 124 */ 125 ret = 1; 126 if (remaining <= 0) 127 goto fail; 128 129 /* OK, here is the one we will use. HEAD is 130 * non-NULL and we hold it's mutex. 131 */ 132 snum = rover; 133 } else { 134 head = &hashinfo->bhash[inet_bhashfn(net, snum, 135 hashinfo->bhash_size)]; 136 spin_lock(&head->lock); 137 inet_bind_bucket_for_each(tb, node, &head->chain) 138 if (tb->ib_net == net && tb->port == snum) 139 goto tb_found; 140 } 141 tb = NULL; 142 goto tb_not_found; 143tb_found: 144 if (!hlist_empty(&tb->owners)) { 145 if (tb->fastreuse > 0 && 146 sk->sk_reuse && sk->sk_state != TCP_LISTEN) { 147 goto success; 148 } else { 149 ret = 1; 150 if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) 151 goto fail_unlock; 152 } 153 } 154tb_not_found: 155 ret = 1; 156 if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep, 157 net, head, snum)) == NULL) 158 goto fail_unlock; 159 if (hlist_empty(&tb->owners)) { 160 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN) 161 tb->fastreuse = 1; 162 else 163 tb->fastreuse = 0; 164 } else if (tb->fastreuse && 165 (!sk->sk_reuse || sk->sk_state == TCP_LISTEN)) 166 tb->fastreuse = 0; 167success: 168 if (!inet_csk(sk)->icsk_bind_hash) 169 inet_bind_hash(sk, tb, snum); 170 WARN_ON(inet_csk(sk)->icsk_bind_hash != tb); 171 ret = 0; 172 173fail_unlock: 174 spin_unlock(&head->lock); 175fail: 176 local_bh_enable(); 177 return ret; 178} 179 180EXPORT_SYMBOL_GPL(inet_csk_get_port); 181 182/* 183 * Wait for an incoming connection, avoid race conditions. This must be called 184 * with the socket locked. 185 */ 186static int inet_csk_wait_for_connect(struct sock *sk, long timeo) 187{ 188 struct inet_connection_sock *icsk = inet_csk(sk); 189 DEFINE_WAIT(wait); 190 int err; 191 192 /* 193 * True wake-one mechanism for incoming connections: only 194 * one process gets woken up, not the 'whole herd'. 195 * Since we do not 'race & poll' for established sockets 196 * anymore, the common case will execute the loop only once. 197 * 198 * Subtle issue: "add_wait_queue_exclusive()" will be added 199 * after any current non-exclusive waiters, and we know that 200 * it will always _stay_ after any new non-exclusive waiters 201 * because all non-exclusive waiters are added at the 202 * beginning of the wait-queue. As such, it's ok to "drop" 203 * our exclusiveness temporarily when we get woken up without 204 * having to remove and re-insert us on the wait queue. 205 */ 206 for (;;) { 207 prepare_to_wait_exclusive(sk->sk_sleep, &wait, 208 TASK_INTERRUPTIBLE); 209 release_sock(sk); 210 if (reqsk_queue_empty(&icsk->icsk_accept_queue)) 211 timeo = schedule_timeout(timeo); 212 lock_sock(sk); 213 err = 0; 214 if (!reqsk_queue_empty(&icsk->icsk_accept_queue)) 215 break; 216 err = -EINVAL; 217 if (sk->sk_state != TCP_LISTEN) 218 break; 219 err = sock_intr_errno(timeo); 220 if (signal_pending(current)) 221 break; 222 err = -EAGAIN; 223 if (!timeo) 224 break; 225 } 226 finish_wait(sk->sk_sleep, &wait); 227 return err; 228} 229 230/* 231 * This will accept the next outstanding connection. 232 */ 233struct sock *inet_csk_accept(struct sock *sk, int flags, int *err) 234{ 235 struct inet_connection_sock *icsk = inet_csk(sk); 236 struct sock *newsk; 237 int error; 238 239 lock_sock(sk); 240 241 /* We need to make sure that this socket is listening, 242 * and that it has something pending. 243 */ 244 error = -EINVAL; 245 if (sk->sk_state != TCP_LISTEN) 246 goto out_err; 247 248 /* Find already established connection */ 249 if (reqsk_queue_empty(&icsk->icsk_accept_queue)) { 250 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); 251 252 /* If this is a non blocking socket don't sleep */ 253 error = -EAGAIN; 254 if (!timeo) 255 goto out_err; 256 257 error = inet_csk_wait_for_connect(sk, timeo); 258 if (error) 259 goto out_err; 260 } 261 262 newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk); 263 WARN_ON(newsk->sk_state == TCP_SYN_RECV); 264out: 265 release_sock(sk); 266 return newsk; 267out_err: 268 newsk = NULL; 269 *err = error; 270 goto out; 271} 272 273EXPORT_SYMBOL(inet_csk_accept); 274 275/* 276 * Using different timers for retransmit, delayed acks and probes 277 * We may wish use just one timer maintaining a list of expire jiffies 278 * to optimize. 279 */ 280void inet_csk_init_xmit_timers(struct sock *sk, 281 void (*retransmit_handler)(unsigned long), 282 void (*delack_handler)(unsigned long), 283 void (*keepalive_handler)(unsigned long)) 284{ 285 struct inet_connection_sock *icsk = inet_csk(sk); 286 287 setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler, 288 (unsigned long)sk); 289 setup_timer(&icsk->icsk_delack_timer, delack_handler, 290 (unsigned long)sk); 291 setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk); 292 icsk->icsk_pending = icsk->icsk_ack.pending = 0; 293} 294 295EXPORT_SYMBOL(inet_csk_init_xmit_timers); 296 297void inet_csk_clear_xmit_timers(struct sock *sk) 298{ 299 struct inet_connection_sock *icsk = inet_csk(sk); 300 301 icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0; 302 303 sk_stop_timer(sk, &icsk->icsk_retransmit_timer); 304 sk_stop_timer(sk, &icsk->icsk_delack_timer); 305 sk_stop_timer(sk, &sk->sk_timer); 306} 307 308EXPORT_SYMBOL(inet_csk_clear_xmit_timers); 309 310void inet_csk_delete_keepalive_timer(struct sock *sk) 311{ 312 sk_stop_timer(sk, &sk->sk_timer); 313} 314 315EXPORT_SYMBOL(inet_csk_delete_keepalive_timer); 316 317void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len) 318{ 319 sk_reset_timer(sk, &sk->sk_timer, jiffies + len); 320} 321 322EXPORT_SYMBOL(inet_csk_reset_keepalive_timer); 323 324struct dst_entry* inet_csk_route_req(struct sock *sk, 325 const struct request_sock *req) 326{ 327 struct rtable *rt; 328 const struct inet_request_sock *ireq = inet_rsk(req); 329 struct ip_options *opt = inet_rsk(req)->opt; 330 struct flowi fl = { .oif = sk->sk_bound_dev_if, 331 .nl_u = { .ip4_u = 332 { .daddr = ((opt && opt->srr) ? 333 opt->faddr : 334 ireq->rmt_addr), 335 .saddr = ireq->loc_addr, 336 .tos = RT_CONN_FLAGS(sk) } }, 337 .proto = sk->sk_protocol, 338 .flags = inet_sk_flowi_flags(sk), 339 .uli_u = { .ports = 340 { .sport = inet_sk(sk)->sport, 341 .dport = ireq->rmt_port } } }; 342 struct net *net = sock_net(sk); 343 344 security_req_classify_flow(req, &fl); 345 if (ip_route_output_flow(net, &rt, &fl, sk, 0)) { 346 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); 347 return NULL; 348 } 349 if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) { 350 ip_rt_put(rt); 351 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); 352 return NULL; 353 } 354 return &rt->u.dst; 355} 356 357EXPORT_SYMBOL_GPL(inet_csk_route_req); 358 359static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport, 360 const u32 rnd, const u32 synq_hsize) 361{ 362 return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1); 363} 364 365#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 366#define AF_INET_FAMILY(fam) ((fam) == AF_INET) 367#else 368#define AF_INET_FAMILY(fam) 1 369#endif 370 371struct request_sock *inet_csk_search_req(const struct sock *sk, 372 struct request_sock ***prevp, 373 const __be16 rport, const __be32 raddr, 374 const __be32 laddr) 375{ 376 const struct inet_connection_sock *icsk = inet_csk(sk); 377 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 378 struct request_sock *req, **prev; 379 380 for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd, 381 lopt->nr_table_entries)]; 382 (req = *prev) != NULL; 383 prev = &req->dl_next) { 384 const struct inet_request_sock *ireq = inet_rsk(req); 385 386 if (ireq->rmt_port == rport && 387 ireq->rmt_addr == raddr && 388 ireq->loc_addr == laddr && 389 AF_INET_FAMILY(req->rsk_ops->family)) { 390 WARN_ON(req->sk); 391 *prevp = prev; 392 break; 393 } 394 } 395 396 return req; 397} 398 399EXPORT_SYMBOL_GPL(inet_csk_search_req); 400 401void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req, 402 unsigned long timeout) 403{ 404 struct inet_connection_sock *icsk = inet_csk(sk); 405 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 406 const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port, 407 lopt->hash_rnd, lopt->nr_table_entries); 408 409 reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout); 410 inet_csk_reqsk_queue_added(sk, timeout); 411} 412 413/* Only thing we need from tcp.h */ 414extern int sysctl_tcp_synack_retries; 415 416EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add); 417 418void inet_csk_reqsk_queue_prune(struct sock *parent, 419 const unsigned long interval, 420 const unsigned long timeout, 421 const unsigned long max_rto) 422{ 423 struct inet_connection_sock *icsk = inet_csk(parent); 424 struct request_sock_queue *queue = &icsk->icsk_accept_queue; 425 struct listen_sock *lopt = queue->listen_opt; 426 int max_retries = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries; 427 int thresh = max_retries; 428 unsigned long now = jiffies; 429 struct request_sock **reqp, *req; 430 int i, budget; 431 432 if (lopt == NULL || lopt->qlen == 0) 433 return; 434 435 /* Normally all the openreqs are young and become mature 436 * (i.e. converted to established socket) for first timeout. 437 * If synack was not acknowledged for 3 seconds, it means 438 * one of the following things: synack was lost, ack was lost, 439 * rtt is high or nobody planned to ack (i.e. synflood). 440 * When server is a bit loaded, queue is populated with old 441 * open requests, reducing effective size of queue. 442 * When server is well loaded, queue size reduces to zero 443 * after several minutes of work. It is not synflood, 444 * it is normal operation. The solution is pruning 445 * too old entries overriding normal timeout, when 446 * situation becomes dangerous. 447 * 448 * Essentially, we reserve half of room for young 449 * embrions; and abort old ones without pity, if old 450 * ones are about to clog our table. 451 */ 452 if (lopt->qlen>>(lopt->max_qlen_log-1)) { 453 int young = (lopt->qlen_young<<1); 454 455 while (thresh > 2) { 456 if (lopt->qlen < young) 457 break; 458 thresh--; 459 young <<= 1; 460 } 461 } 462 463 if (queue->rskq_defer_accept) 464 max_retries = queue->rskq_defer_accept; 465 466 budget = 2 * (lopt->nr_table_entries / (timeout / interval)); 467 i = lopt->clock_hand; 468 469 do { 470 reqp=&lopt->syn_table[i]; 471 while ((req = *reqp) != NULL) { 472 if (time_after_eq(now, req->expires)) { 473 if ((req->retrans < thresh || 474 (inet_rsk(req)->acked && req->retrans < max_retries)) 475 && !req->rsk_ops->rtx_syn_ack(parent, req)) { 476 unsigned long timeo; 477 478 if (req->retrans++ == 0) 479 lopt->qlen_young--; 480 timeo = min((timeout << req->retrans), max_rto); 481 req->expires = now + timeo; 482 reqp = &req->dl_next; 483 continue; 484 } 485 486 /* Drop this request */ 487 inet_csk_reqsk_queue_unlink(parent, req, reqp); 488 reqsk_queue_removed(queue, req); 489 reqsk_free(req); 490 continue; 491 } 492 reqp = &req->dl_next; 493 } 494 495 i = (i + 1) & (lopt->nr_table_entries - 1); 496 497 } while (--budget > 0); 498 499 lopt->clock_hand = i; 500 501 if (lopt->qlen) 502 inet_csk_reset_keepalive_timer(parent, interval); 503} 504 505EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune); 506 507struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req, 508 const gfp_t priority) 509{ 510 struct sock *newsk = sk_clone(sk, priority); 511 512 if (newsk != NULL) { 513 struct inet_connection_sock *newicsk = inet_csk(newsk); 514 515 newsk->sk_state = TCP_SYN_RECV; 516 newicsk->icsk_bind_hash = NULL; 517 518 inet_sk(newsk)->dport = inet_rsk(req)->rmt_port; 519 newsk->sk_write_space = sk_stream_write_space; 520 521 newicsk->icsk_retransmits = 0; 522 newicsk->icsk_backoff = 0; 523 newicsk->icsk_probes_out = 0; 524 525 /* Deinitialize accept_queue to trap illegal accesses. */ 526 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue)); 527 528 security_inet_csk_clone(newsk, req); 529 } 530 return newsk; 531} 532 533EXPORT_SYMBOL_GPL(inet_csk_clone); 534 535/* 536 * At this point, there should be no process reference to this 537 * socket, and thus no user references at all. Therefore we 538 * can assume the socket waitqueue is inactive and nobody will 539 * try to jump onto it. 540 */ 541void inet_csk_destroy_sock(struct sock *sk) 542{ 543 WARN_ON(sk->sk_state != TCP_CLOSE); 544 WARN_ON(!sock_flag(sk, SOCK_DEAD)); 545 546 /* It cannot be in hash table! */ 547 WARN_ON(!sk_unhashed(sk)); 548 549 /* If it has not 0 inet_sk(sk)->num, it must be bound */ 550 WARN_ON(inet_sk(sk)->num && !inet_csk(sk)->icsk_bind_hash); 551 552 sk->sk_prot->destroy(sk); 553 554 sk_stream_kill_queues(sk); 555 556 xfrm_sk_free_policy(sk); 557 558 sk_refcnt_debug_release(sk); 559 560 atomic_dec(sk->sk_prot->orphan_count); 561 sock_put(sk); 562} 563 564EXPORT_SYMBOL(inet_csk_destroy_sock); 565 566int inet_csk_listen_start(struct sock *sk, const int nr_table_entries) 567{ 568 struct inet_sock *inet = inet_sk(sk); 569 struct inet_connection_sock *icsk = inet_csk(sk); 570 int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries); 571 572 if (rc != 0) 573 return rc; 574 575 sk->sk_max_ack_backlog = 0; 576 sk->sk_ack_backlog = 0; 577 inet_csk_delack_init(sk); 578 579 /* There is race window here: we announce ourselves listening, 580 * but this transition is still not validated by get_port(). 581 * It is OK, because this socket enters to hash table only 582 * after validation is complete. 583 */ 584 sk->sk_state = TCP_LISTEN; 585 if (!sk->sk_prot->get_port(sk, inet->num)) { 586 inet->sport = htons(inet->num); 587 588 sk_dst_reset(sk); 589 sk->sk_prot->hash(sk); 590 591 return 0; 592 } 593 594 sk->sk_state = TCP_CLOSE; 595 __reqsk_queue_destroy(&icsk->icsk_accept_queue); 596 return -EADDRINUSE; 597} 598 599EXPORT_SYMBOL_GPL(inet_csk_listen_start); 600 601/* 602 * This routine closes sockets which have been at least partially 603 * opened, but not yet accepted. 604 */ 605void inet_csk_listen_stop(struct sock *sk) 606{ 607 struct inet_connection_sock *icsk = inet_csk(sk); 608 struct request_sock *acc_req; 609 struct request_sock *req; 610 611 inet_csk_delete_keepalive_timer(sk); 612 613 /* make all the listen_opt local to us */ 614 acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue); 615 616 /* Following specs, it would be better either to send FIN 617 * (and enter FIN-WAIT-1, it is normal close) 618 * or to send active reset (abort). 619 * Certainly, it is pretty dangerous while synflood, but it is 620 * bad justification for our negligence 8) 621 * To be honest, we are not able to make either 622 * of the variants now. --ANK 623 */ 624 reqsk_queue_destroy(&icsk->icsk_accept_queue); 625 626 while ((req = acc_req) != NULL) { 627 struct sock *child = req->sk; 628 629 acc_req = req->dl_next; 630 631 local_bh_disable(); 632 bh_lock_sock(child); 633 WARN_ON(sock_owned_by_user(child)); 634 sock_hold(child); 635 636 sk->sk_prot->disconnect(child, O_NONBLOCK); 637 638 sock_orphan(child); 639 640 atomic_inc(sk->sk_prot->orphan_count); 641 642 inet_csk_destroy_sock(child); 643 644 bh_unlock_sock(child); 645 local_bh_enable(); 646 sock_put(child); 647 648 sk_acceptq_removed(sk); 649 __reqsk_free(req); 650 } 651 WARN_ON(sk->sk_ack_backlog); 652} 653 654EXPORT_SYMBOL_GPL(inet_csk_listen_stop); 655 656void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) 657{ 658 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr; 659 const struct inet_sock *inet = inet_sk(sk); 660 661 sin->sin_family = AF_INET; 662 sin->sin_addr.s_addr = inet->daddr; 663 sin->sin_port = inet->dport; 664} 665 666EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr); 667 668#ifdef CONFIG_COMPAT 669int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname, 670 char __user *optval, int __user *optlen) 671{ 672 const struct inet_connection_sock *icsk = inet_csk(sk); 673 674 if (icsk->icsk_af_ops->compat_getsockopt != NULL) 675 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname, 676 optval, optlen); 677 return icsk->icsk_af_ops->getsockopt(sk, level, optname, 678 optval, optlen); 679} 680 681EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt); 682 683int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, 684 char __user *optval, int optlen) 685{ 686 const struct inet_connection_sock *icsk = inet_csk(sk); 687 688 if (icsk->icsk_af_ops->compat_setsockopt != NULL) 689 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname, 690 optval, optlen); 691 return icsk->icsk_af_ops->setsockopt(sk, level, optname, 692 optval, optlen); 693} 694 695EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt); 696#endif 697