net/ipv4/inet_connection_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  *              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
  28 const char inet_csk_timer_bug_msg[] = "inet_csk BUG: unknown timer value\n";
  29 EXPORT_SYMBOL(inet_csk_timer_bug_msg);
  30 #endif
  31
  32 /*
  33  * This array holds the first and last local port number.
  34  */
  35 int sysctl_local_port_range[2] = { 32768, 61000 };
  36 DEFINE_SEQLOCK(sysctl_port_range_lock);
  37
  38 void 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 }
  48 EXPORT_SYMBOL(inet_get_local_port_range);
  49
  50 int 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         sk_for_each_bound(sk2, node, &tb->owners) {
  59                 if (sk != sk2 &&
  60                     !inet_v6_ipv6only(sk2) &&
  61                     (!sk->sk_bound_dev_if ||
  62                      !sk2->sk_bound_dev_if ||
  63                      sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
  64                         if (!reuse || !sk2->sk_reuse ||
  65                             sk2->sk_state == TCP_LISTEN) {
  66                                 const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
  67                                 if (!sk2_rcv_saddr || !sk_rcv_saddr ||
  68                                     sk2_rcv_saddr == sk_rcv_saddr)
  69                                         break;
  70                         }
  71                 }
  72         }
  73         return node != NULL;
  74 }
  75
  76 EXPORT_SYMBOL_GPL(inet_csk_bind_conflict);
  77
  78 /* Obtain a reference to a local port for the given sock,
  79  * if snum is zero it means select any available local port.
  80  */
  81 int inet_csk_get_port(struct sock *sk, unsigned short snum)
  82 {
  83         struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
  84         struct inet_bind_hashbucket *head;
  85         struct hlist_node *node;
  86         struct inet_bind_bucket *tb;
  87         int ret;
  88         struct net *net = sock_net(sk);
  89
  90         local_bh_disable();
  91         if (!snum) {
  92                 int remaining, rover, low, high;
  93
  94                 inet_get_local_port_range(&low, &high);
  95                 remaining = (high - low) + 1;
  96                 rover = net_random() % remaining + low;
  97
  98                 do {
  99                         head = &hashinfo->bhash[inet_bhashfn(rover, hashinfo->bhash_size)];
 100                         spin_lock(&head->lock);
 101                         inet_bind_bucket_for_each(tb, node, &head->chain)
 102                                 if (tb->ib_net == net && tb->port == rover)
 103                                         goto next;
 104                         break;
 105                 next:
 106                         spin_unlock(&head->lock);
 107                         if (++rover > high)
 108                                 rover = low;
 109                 } while (--remaining > 0);
 110
 111                 /* Exhausted local port range during search?  It is not
 112                  * possible for us to be holding one of the bind hash
 113                  * locks if this test triggers, because if 'remaining'
 114                  * drops to zero, we broke out of the do/while loop at
 115                  * the top level, not from the 'break;' statement.
 116                  */
 117                 ret = 1;
 118                 if (remaining <= 0)
 119                         goto fail;
 120
 121                 /* OK, here is the one we will use.  HEAD is
 122                  * non-NULL and we hold it's mutex.
 123                  */
 124                 snum = rover;
 125         } else {
 126                 head = &hashinfo->bhash[inet_bhashfn(snum, hashinfo->bhash_size)];
 127                 spin_lock(&head->lock);
 128                 inet_bind_bucket_for_each(tb, node, &head->chain)
 129                         if (tb->ib_net == net && tb->port == snum)
 130                                 goto tb_found;
 131         }
 132         tb = NULL;
 133         goto tb_not_found;
 134 tb_found:
 135         if (!hlist_empty(&tb->owners)) {
 136                 if (tb->fastreuse > 0 &&
 137                     sk->sk_reuse && sk->sk_state != TCP_LISTEN) {
 138                         goto success;
 139                 } else {
 140                         ret = 1;
 141                         if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb))
 142                                 goto fail_unlock;
 143                 }
 144         }
 145 tb_not_found:
 146         ret = 1;
 147         if (!tb && (tb = inet_bind_bucket_create(hashinfo->bind_bucket_cachep,
 148                                         net, head, snum)) == NULL)
 149                 goto fail_unlock;
 150         if (hlist_empty(&tb->owners)) {
 151                 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
 152                         tb->fastreuse = 1;
 153                 else
 154                         tb->fastreuse = 0;
 155         } else if (tb->fastreuse &&
 156                    (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
 157                 tb->fastreuse = 0;
 158 success:
 159         if (!inet_csk(sk)->icsk_bind_hash)
 160                 inet_bind_hash(sk, tb, snum);
 161         BUG_TRAP(inet_csk(sk)->icsk_bind_hash == tb);
 162         ret = 0;
 163
 164 fail_unlock:
 165         spin_unlock(&head->lock);
 166 fail:
 167         local_bh_enable();
 168         return ret;
 169 }
 170
 171 EXPORT_SYMBOL_GPL(inet_csk_get_port);
 172
 173 /*
 174  * Wait for an incoming connection, avoid race conditions. This must be called
 175  * with the socket locked.
 176  */
 177 static int inet_csk_wait_for_connect(struct sock *sk, long timeo)
 178 {
 179         struct inet_connection_sock *icsk = inet_csk(sk);
 180         DEFINE_WAIT(wait);
 181         int err;
 182
 183         /*
 184          * True wake-one mechanism for incoming connections: only
 185          * one process gets woken up, not the 'whole herd'.
 186          * Since we do not 'race & poll' for established sockets
 187          * anymore, the common case will execute the loop only once.
 188          *
 189          * Subtle issue: "add_wait_queue_exclusive()" will be added
 190          * after any current non-exclusive waiters, and we know that
 191          * it will always _stay_ after any new non-exclusive waiters
 192          * because all non-exclusive waiters are added at the
 193          * beginning of the wait-queue. As such, it's ok to "drop"
 194          * our exclusiveness temporarily when we get woken up without
 195          * having to remove and re-insert us on the wait queue.
 196          */
 197         for (;;) {
 198                 prepare_to_wait_exclusive(sk->sk_sleep, &wait,
 199                                           TASK_INTERRUPTIBLE);
 200                 release_sock(sk);
 201                 if (reqsk_queue_empty(&icsk->icsk_accept_queue))
 202                         timeo = schedule_timeout(timeo);
 203                 lock_sock(sk);
 204                 err = 0;
 205                 if (!reqsk_queue_empty(&icsk->icsk_accept_queue))
 206                         break;
 207                 err = -EINVAL;
 208                 if (sk->sk_state != TCP_LISTEN)
 209                         break;
 210                 err = sock_intr_errno(timeo);
 211                 if (signal_pending(current))
 212                         break;
 213                 err = -EAGAIN;
 214                 if (!timeo)
 215                         break;
 216         }
 217         finish_wait(sk->sk_sleep, &wait);
 218         return err;
 219 }
 220
 221 /*
 222  * This will accept the next outstanding connection.
 223  */
 224 struct sock *inet_csk_accept(struct sock *sk, int flags, int *err)
 225 {
 226         struct inet_connection_sock *icsk = inet_csk(sk);
 227         struct sock *newsk;
 228         int error;
 229
 230         lock_sock(sk);
 231
 232         /* We need to make sure that this socket is listening,
 233          * and that it has something pending.
 234          */
 235         error = -EINVAL;
 236         if (sk->sk_state != TCP_LISTEN)
 237                 goto out_err;
 238
 239         /* Find already established connection */
 240         if (reqsk_queue_empty(&icsk->icsk_accept_queue)) {
 241                 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
 242
 243                 /* If this is a non blocking socket don't sleep */
 244                 error = -EAGAIN;
 245                 if (!timeo)
 246                         goto out_err;
 247
 248                 error = inet_csk_wait_for_connect(sk, timeo);
 249                 if (error)
 250                         goto out_err;
 251         }
 252
 253         newsk = reqsk_queue_get_child(&icsk->icsk_accept_queue, sk);
 254         BUG_TRAP(newsk->sk_state != TCP_SYN_RECV);
 255 out:
 256         release_sock(sk);
 257         return newsk;
 258 out_err:
 259         newsk = NULL;
 260         *err = error;
 261         goto out;
 262 }
 263
 264 EXPORT_SYMBOL(inet_csk_accept);
 265
 266 /*
 267  * Using different timers for retransmit, delayed acks and probes
 268  * We may wish use just one timer maintaining a list of expire jiffies
 269  * to optimize.
 270  */
 271 void inet_csk_init_xmit_timers(struct sock *sk,
 272                                void (*retransmit_handler)(unsigned long),
 273                                void (*delack_handler)(unsigned long),
 274                                void (*keepalive_handler)(unsigned long))
 275 {
 276         struct inet_connection_sock *icsk = inet_csk(sk);
 277
 278         setup_timer(&icsk->icsk_retransmit_timer, retransmit_handler,
 279                         (unsigned long)sk);
 280         setup_timer(&icsk->icsk_delack_timer, delack_handler,
 281                         (unsigned long)sk);
 282         setup_timer(&sk->sk_timer, keepalive_handler, (unsigned long)sk);
 283         icsk->icsk_pending = icsk->icsk_ack.pending = 0;
 284 }
 285
 286 EXPORT_SYMBOL(inet_csk_init_xmit_timers);
 287
 288 void inet_csk_clear_xmit_timers(struct sock *sk)
 289 {
 290         struct inet_connection_sock *icsk = inet_csk(sk);
 291
 292         icsk->icsk_pending = icsk->icsk_ack.pending = icsk->icsk_ack.blocked = 0;
 293
 294         sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
 295         sk_stop_timer(sk, &icsk->icsk_delack_timer);
 296         sk_stop_timer(sk, &sk->sk_timer);
 297 }
 298
 299 EXPORT_SYMBOL(inet_csk_clear_xmit_timers);
 300
 301 void inet_csk_delete_keepalive_timer(struct sock *sk)
 302 {
 303         sk_stop_timer(sk, &sk->sk_timer);
 304 }
 305
 306 EXPORT_SYMBOL(inet_csk_delete_keepalive_timer);
 307
 308 void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long len)
 309 {
 310         sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
 311 }
 312
 313 EXPORT_SYMBOL(inet_csk_reset_keepalive_timer);
 314
 315 struct dst_entry* inet_csk_route_req(struct sock *sk,
 316                                      const struct request_sock *req)
 317 {
 318         struct rtable *rt;
 319         const struct inet_request_sock *ireq = inet_rsk(req);
 320         struct ip_options *opt = inet_rsk(req)->opt;
 321         struct flowi fl = { .oif = sk->sk_bound_dev_if,
 322                             .nl_u = { .ip4_u =
 323                                       { .daddr = ((opt && opt->srr) ?
 324                                                   opt->faddr :
 325                                                   ireq->rmt_addr),
 326                                         .saddr = ireq->loc_addr,
 327                                         .tos = RT_CONN_FLAGS(sk) } },
 328                             .proto = sk->sk_protocol,
 329                             .uli_u = { .ports =
 330                                        { .sport = inet_sk(sk)->sport,
 331                                          .dport = ireq->rmt_port } } };
 332
 333         security_req_classify_flow(req, &fl);
 334         if (ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0)) {
 335                 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
 336                 return NULL;
 337         }
 338         if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) {
 339                 ip_rt_put(rt);
 340                 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
 341                 return NULL;
 342         }
 343         return &rt->u.dst;
 344 }
 345
 346 EXPORT_SYMBOL_GPL(inet_csk_route_req);
 347
 348 static inline u32 inet_synq_hash(const __be32 raddr, const __be16 rport,
 349                                  const u32 rnd, const u32 synq_hsize)
 350 {
 351         return jhash_2words((__force u32)raddr, (__force u32)rport, rnd) & (synq_hsize - 1);
 352 }
 353
 354 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 355 #define AF_INET_FAMILY(fam) ((fam) == AF_INET)
 356 #else
 357 #define AF_INET_FAMILY(fam) 1
 358 #endif
 359
 360 struct request_sock *inet_csk_search_req(const struct sock *sk,
 361                                          struct request_sock ***prevp,
 362                                          const __be16 rport, const __be32 raddr,
 363                                          const __be32 laddr)
 364 {
 365         const struct inet_connection_sock *icsk = inet_csk(sk);
 366         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
 367         struct request_sock *req, **prev;
 368
 369         for (prev = &lopt->syn_table[inet_synq_hash(raddr, rport, lopt->hash_rnd,
 370                                                     lopt->nr_table_entries)];
 371              (req = *prev) != NULL;
 372              prev = &req->dl_next) {
 373                 const struct inet_request_sock *ireq = inet_rsk(req);
 374
 375                 if (ireq->rmt_port == rport &&
 376                     ireq->rmt_addr == raddr &&
 377                     ireq->loc_addr == laddr &&
 378                     AF_INET_FAMILY(req->rsk_ops->family)) {
 379                         BUG_TRAP(!req->sk);
 380                         *prevp = prev;
 381                         break;
 382                 }
 383         }
 384
 385         return req;
 386 }
 387
 388 EXPORT_SYMBOL_GPL(inet_csk_search_req);
 389
 390 void inet_csk_reqsk_queue_hash_add(struct sock *sk, struct request_sock *req,
 391                                    unsigned long timeout)
 392 {
 393         struct inet_connection_sock *icsk = inet_csk(sk);
 394         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
 395         const u32 h = inet_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port,
 396                                      lopt->hash_rnd, lopt->nr_table_entries);
 397
 398         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
 399         inet_csk_reqsk_queue_added(sk, timeout);
 400 }
 401
 402 /* Only thing we need from tcp.h */
 403 extern int sysctl_tcp_synack_retries;
 404
 405 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_hash_add);
 406
 407 void inet_csk_reqsk_queue_prune(struct sock *parent,
 408                                 const unsigned long interval,
 409                                 const unsigned long timeout,
 410                                 const unsigned long max_rto)
 411 {
 412         struct inet_connection_sock *icsk = inet_csk(parent);
 413         struct request_sock_queue *queue = &icsk->icsk_accept_queue;
 414         struct listen_sock *lopt = queue->listen_opt;
 415         int thresh = icsk->icsk_syn_retries ? : sysctl_tcp_synack_retries;
 416         unsigned long now = jiffies;
 417         struct request_sock **reqp, *req;
 418         int i, budget;
 419
 420         if (lopt == NULL || lopt->qlen == 0)
 421                 return;
 422
 423         /* Normally all the openreqs are young and become mature
 424          * (i.e. converted to established socket) for first timeout.
 425          * If synack was not acknowledged for 3 seconds, it means
 426          * one of the following things: synack was lost, ack was lost,
 427          * rtt is high or nobody planned to ack (i.e. synflood).
 428          * When server is a bit loaded, queue is populated with old
 429          * open requests, reducing effective size of queue.
 430          * When server is well loaded, queue size reduces to zero
 431          * after several minutes of work. It is not synflood,
 432          * it is normal operation. The solution is pruning
 433          * too old entries overriding normal timeout, when
 434          * situation becomes dangerous.
 435          *
 436          * Essentially, we reserve half of room for young
 437          * embrions; and abort old ones without pity, if old
 438          * ones are about to clog our table.
 439          */
 440         if (lopt->qlen>>(lopt->max_qlen_log-1)) {
 441                 int young = (lopt->qlen_young<<1);
 442
 443                 while (thresh > 2) {
 444                         if (lopt->qlen < young)
 445                                 break;
 446                         thresh--;
 447                         young <<= 1;
 448                 }
 449         }
 450
 451         budget = 2 * (lopt->nr_table_entries / (timeout / interval));
 452         i = lopt->clock_hand;
 453
 454         do {
 455                 reqp=&lopt->syn_table[i];
 456                 while ((req = *reqp) != NULL) {
 457                         if (time_after_eq(now, req->expires)) {
 458                                 if (req->retrans < thresh &&
 459                                     !req->rsk_ops->rtx_syn_ack(parent, req)) {
 460                                         unsigned long timeo;
 461
 462                                         if (req->retrans++ == 0)
 463                                                 lopt->qlen_young--;
 464                                         timeo = min((timeout << req->retrans), max_rto);
 465                                         req->expires = now + timeo;
 466                                         reqp = &req->dl_next;
 467                                         continue;
 468                                 }
 469
 470                                 /* Drop this request */
 471                                 inet_csk_reqsk_queue_unlink(parent, req, reqp);
 472                                 reqsk_queue_removed(queue, req);
 473                                 reqsk_free(req);
 474                                 continue;
 475                         }
 476                         reqp = &req->dl_next;
 477                 }
 478
 479                 i = (i + 1) & (lopt->nr_table_entries - 1);
 480
 481         } while (--budget > 0);
 482
 483         lopt->clock_hand = i;
 484
 485         if (lopt->qlen)
 486                 inet_csk_reset_keepalive_timer(parent, interval);
 487 }
 488
 489 EXPORT_SYMBOL_GPL(inet_csk_reqsk_queue_prune);
 490
 491 struct sock *inet_csk_clone(struct sock *sk, const struct request_sock *req,
 492                             const gfp_t priority)
 493 {
 494         struct sock *newsk = sk_clone(sk, priority);
 495
 496         if (newsk != NULL) {
 497                 struct inet_connection_sock *newicsk = inet_csk(newsk);
 498
 499                 newsk->sk_state = TCP_SYN_RECV;
 500                 newicsk->icsk_bind_hash = NULL;
 501
 502                 inet_sk(newsk)->dport = inet_rsk(req)->rmt_port;
 503                 newsk->sk_write_space = sk_stream_write_space;
 504
 505                 newicsk->icsk_retransmits = 0;
 506                 newicsk->icsk_backoff     = 0;
 507                 newicsk->icsk_probes_out  = 0;
 508
 509                 /* Deinitialize accept_queue to trap illegal accesses. */
 510                 memset(&newicsk->icsk_accept_queue, 0, sizeof(newicsk->icsk_accept_queue));
 511
 512                 security_inet_csk_clone(newsk, req);
 513         }
 514         return newsk;
 515 }
 516
 517 EXPORT_SYMBOL_GPL(inet_csk_clone);
 518
 519 /*
 520  * At this point, there should be no process reference to this
 521  * socket, and thus no user references at all.  Therefore we
 522  * can assume the socket waitqueue is inactive and nobody will
 523  * try to jump onto it.
 524  */
 525 void inet_csk_destroy_sock(struct sock *sk)
 526 {
 527         BUG_TRAP(sk->sk_state == TCP_CLOSE);
 528         BUG_TRAP(sock_flag(sk, SOCK_DEAD));
 529
 530         /* It cannot be in hash table! */
 531         BUG_TRAP(sk_unhashed(sk));
 532
 533         /* If it has not 0 inet_sk(sk)->num, it must be bound */
 534         BUG_TRAP(!inet_sk(sk)->num || inet_csk(sk)->icsk_bind_hash);
 535
 536         sk->sk_prot->destroy(sk);
 537
 538         sk_stream_kill_queues(sk);
 539
 540         xfrm_sk_free_policy(sk);
 541
 542         sk_refcnt_debug_release(sk);
 543
 544         atomic_dec(sk->sk_prot->orphan_count);
 545         sock_put(sk);
 546 }
 547
 548 EXPORT_SYMBOL(inet_csk_destroy_sock);
 549
 550 int inet_csk_listen_start(struct sock *sk, const int nr_table_entries)
 551 {
 552         struct inet_sock *inet = inet_sk(sk);
 553         struct inet_connection_sock *icsk = inet_csk(sk);
 554         int rc = reqsk_queue_alloc(&icsk->icsk_accept_queue, nr_table_entries);
 555
 556         if (rc != 0)
 557                 return rc;
 558
 559         sk->sk_max_ack_backlog = 0;
 560         sk->sk_ack_backlog = 0;
 561         inet_csk_delack_init(sk);
 562
 563         /* There is race window here: we announce ourselves listening,
 564          * but this transition is still not validated by get_port().
 565          * It is OK, because this socket enters to hash table only
 566          * after validation is complete.
 567          */
 568         sk->sk_state = TCP_LISTEN;
 569         if (!sk->sk_prot->get_port(sk, inet->num)) {
 570                 inet->sport = htons(inet->num);
 571
 572                 sk_dst_reset(sk);
 573                 sk->sk_prot->hash(sk);
 574
 575                 return 0;
 576         }
 577
 578         sk->sk_state = TCP_CLOSE;
 579         __reqsk_queue_destroy(&icsk->icsk_accept_queue);
 580         return -EADDRINUSE;
 581 }
 582
 583 EXPORT_SYMBOL_GPL(inet_csk_listen_start);
 584
 585 /*
 586  *      This routine closes sockets which have been at least partially
 587  *      opened, but not yet accepted.
 588  */
 589 void inet_csk_listen_stop(struct sock *sk)
 590 {
 591         struct inet_connection_sock *icsk = inet_csk(sk);
 592         struct request_sock *acc_req;
 593         struct request_sock *req;
 594
 595         inet_csk_delete_keepalive_timer(sk);
 596
 597         /* make all the listen_opt local to us */
 598         acc_req = reqsk_queue_yank_acceptq(&icsk->icsk_accept_queue);
 599
 600         /* Following specs, it would be better either to send FIN
 601          * (and enter FIN-WAIT-1, it is normal close)
 602          * or to send active reset (abort).
 603          * Certainly, it is pretty dangerous while synflood, but it is
 604          * bad justification for our negligence 8)
 605          * To be honest, we are not able to make either
 606          * of the variants now.                 --ANK
 607          */
 608         reqsk_queue_destroy(&icsk->icsk_accept_queue);
 609
 610         while ((req = acc_req) != NULL) {
 611                 struct sock *child = req->sk;
 612
 613                 acc_req = req->dl_next;
 614
 615                 local_bh_disable();
 616                 bh_lock_sock(child);
 617                 BUG_TRAP(!sock_owned_by_user(child));
 618                 sock_hold(child);
 619
 620                 sk->sk_prot->disconnect(child, O_NONBLOCK);
 621
 622                 sock_orphan(child);
 623
 624                 atomic_inc(sk->sk_prot->orphan_count);
 625
 626                 inet_csk_destroy_sock(child);
 627
 628                 bh_unlock_sock(child);
 629                 local_bh_enable();
 630                 sock_put(child);
 631
 632                 sk_acceptq_removed(sk);
 633                 __reqsk_free(req);
 634         }
 635         BUG_TRAP(!sk->sk_ack_backlog);
 636 }
 637
 638 EXPORT_SYMBOL_GPL(inet_csk_listen_stop);
 639
 640 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
 641 {
 642         struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
 643         const struct inet_sock *inet = inet_sk(sk);
 644
 645         sin->sin_family         = AF_INET;
 646         sin->sin_addr.s_addr    = inet->daddr;
 647         sin->sin_port           = inet->dport;
 648 }
 649
 650 EXPORT_SYMBOL_GPL(inet_csk_addr2sockaddr);
 651
 652 #ifdef CONFIG_COMPAT
 653 int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
 654                                char __user *optval, int __user *optlen)
 655 {
 656         const struct inet_connection_sock *icsk = inet_csk(sk);
 657
 658         if (icsk->icsk_af_ops->compat_getsockopt != NULL)
 659                 return icsk->icsk_af_ops->compat_getsockopt(sk, level, optname,
 660                                                             optval, optlen);
 661         return icsk->icsk_af_ops->getsockopt(sk, level, optname,
 662                                              optval, optlen);
 663 }
 664
 665 EXPORT_SYMBOL_GPL(inet_csk_compat_getsockopt);
 666
 667 int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
 668                                char __user *optval, int optlen)
 669 {
 670         const struct inet_connection_sock *icsk = inet_csk(sk);
 671
 672         if (icsk->icsk_af_ops->compat_setsockopt != NULL)
 673                 return icsk->icsk_af_ops->compat_setsockopt(sk, level, optname,
 674                                                             optval, optlen);
 675         return icsk->icsk_af_ops->setsockopt(sk, level, optname,
 676                                              optval, optlen);
 677 }
 678
 679 EXPORT_SYMBOL_GPL(inet_csk_compat_setsockopt);
 680 #endif