net/ipv4/inet_hashtables.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   4  *              operating system.  INET is implemented using the BSD Socket
   5  *              interface as the means of communication with the user level.
   6  *
   7  *              Generic INET transport hashtables
   8  *
   9  * Authors:     Lotsa people, from code originally in tcp
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/random.h>
  14 #include <linux/sched.h>
  15 #include <linux/slab.h>
  16 #include <linux/wait.h>
  17 #include <linux/vmalloc.h>
  18 #include <linux/memblock.h>
  19
  20 #include <net/addrconf.h>
  21 #include <net/inet_connection_sock.h>
  22 #include <net/inet_hashtables.h>
  23 #if IS_ENABLED(CONFIG_IPV6)
  24 #include <net/inet6_hashtables.h>
  25 #endif
  26 #include <net/secure_seq.h>
  27 #include <net/ip.h>
  28 #include <net/tcp.h>
  29 #include <net/sock_reuseport.h>
  30
  31 u32 inet_ehashfn(const struct net *net, const __be32 laddr,
  32                  const __u16 lport, const __be32 faddr,
  33                  const __be16 fport)
  34 {
  35         static u32 inet_ehash_secret __read_mostly;
  36
  37         net_get_random_once(&inet_ehash_secret, sizeof(inet_ehash_secret));
  38
  39         return __inet_ehashfn(laddr, lport, faddr, fport,
  40                               inet_ehash_secret + net_hash_mix(net));
  41 }
  42 EXPORT_SYMBOL_GPL(inet_ehashfn);
  43
  44 /* This function handles inet_sock, but also timewait and request sockets
  45  * for IPv4/IPv6.
  46  */
  47 static u32 sk_ehashfn(const struct sock *sk)
  48 {
  49 #if IS_ENABLED(CONFIG_IPV6)
  50         if (sk->sk_family == AF_INET6 &&
  51             !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
  52                 return inet6_ehashfn(sock_net(sk),
  53                                      &sk->sk_v6_rcv_saddr, sk->sk_num,
  54                                      &sk->sk_v6_daddr, sk->sk_dport);
  55 #endif
  56         return inet_ehashfn(sock_net(sk),
  57                             sk->sk_rcv_saddr, sk->sk_num,
  58                             sk->sk_daddr, sk->sk_dport);
  59 }
  60
  61 /*
  62  * Allocate and initialize a new local port bind bucket.
  63  * The bindhash mutex for snum's hash chain must be held here.
  64  */
  65 struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
  66                                                  struct net *net,
  67                                                  struct inet_bind_hashbucket *head,
  68                                                  const unsigned short snum,
  69                                                  int l3mdev)
  70 {
  71         struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
  72
  73         if (tb) {
  74                 write_pnet(&tb->ib_net, net);
  75                 tb->l3mdev    = l3mdev;
  76                 tb->port      = snum;
  77                 tb->fastreuse = 0;
  78                 tb->fastreuseport = 0;
  79                 INIT_HLIST_HEAD(&tb->owners);
  80                 hlist_add_head(&tb->node, &head->chain);
  81         }
  82         return tb;
  83 }
  84
  85 /*
  86  * Caller must hold hashbucket lock for this tb with local BH disabled
  87  */
  88 void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket *tb)
  89 {
  90         if (hlist_empty(&tb->owners)) {
  91                 __hlist_del(&tb->node);
  92                 kmem_cache_free(cachep, tb);
  93         }
  94 }
  95
  96 bool inet_bind_bucket_match(const struct inet_bind_bucket *tb, const struct net *net,
  97                             unsigned short port, int l3mdev)
  98 {
  99         return net_eq(ib_net(tb), net) && tb->port == port &&
 100                 tb->l3mdev == l3mdev;
 101 }
 102
 103 static void inet_bind2_bucket_init(struct inet_bind2_bucket *tb,
 104                                    struct net *net,
 105                                    struct inet_bind_hashbucket *head,
 106                                    unsigned short port, int l3mdev,
 107                                    const struct sock *sk)
 108 {
 109         write_pnet(&tb->ib_net, net);
 110         tb->l3mdev    = l3mdev;
 111         tb->port      = port;
 112 #if IS_ENABLED(CONFIG_IPV6)
 113         tb->family    = sk->sk_family;
 114         if (sk->sk_family == AF_INET6)
 115                 tb->v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 116         else
 117 #endif
 118                 tb->rcv_saddr = sk->sk_rcv_saddr;
 119         INIT_HLIST_HEAD(&tb->owners);
 120         INIT_HLIST_HEAD(&tb->deathrow);
 121         hlist_add_head(&tb->node, &head->chain);
 122 }
 123
 124 struct inet_bind2_bucket *inet_bind2_bucket_create(struct kmem_cache *cachep,
 125                                                    struct net *net,
 126                                                    struct inet_bind_hashbucket *head,
 127                                                    unsigned short port,
 128                                                    int l3mdev,
 129                                                    const struct sock *sk)
 130 {
 131         struct inet_bind2_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
 132
 133         if (tb)
 134                 inet_bind2_bucket_init(tb, net, head, port, l3mdev, sk);
 135
 136         return tb;
 137 }
 138
 139 /* Caller must hold hashbucket lock for this tb with local BH disabled */
 140 void inet_bind2_bucket_destroy(struct kmem_cache *cachep, struct inet_bind2_bucket *tb)
 141 {
 142         if (hlist_empty(&tb->owners) && hlist_empty(&tb->deathrow)) {
 143                 __hlist_del(&tb->node);
 144                 kmem_cache_free(cachep, tb);
 145         }
 146 }
 147
 148 static bool inet_bind2_bucket_addr_match(const struct inet_bind2_bucket *tb2,
 149                                          const struct sock *sk)
 150 {
 151 #if IS_ENABLED(CONFIG_IPV6)
 152         if (sk->sk_family != tb2->family)
 153                 return false;
 154
 155         if (sk->sk_family == AF_INET6)
 156                 return ipv6_addr_equal(&tb2->v6_rcv_saddr,
 157                                        &sk->sk_v6_rcv_saddr);
 158 #endif
 159         return tb2->rcv_saddr == sk->sk_rcv_saddr;
 160 }
 161
 162 void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
 163                     struct inet_bind2_bucket *tb2, unsigned short port)
 164 {
 165         inet_sk(sk)->inet_num = port;
 166         sk_add_bind_node(sk, &tb->owners);
 167         inet_csk(sk)->icsk_bind_hash = tb;
 168         sk_add_bind2_node(sk, &tb2->owners);
 169         inet_csk(sk)->icsk_bind2_hash = tb2;
 170 }
 171
 172 /*
 173  * Get rid of any references to a local port held by the given sock.
 174  */
 175 static void __inet_put_port(struct sock *sk)
 176 {
 177         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 178         struct inet_bind_hashbucket *head, *head2;
 179         struct net *net = sock_net(sk);
 180         struct inet_bind_bucket *tb;
 181         int bhash;
 182
 183         bhash = inet_bhashfn(net, inet_sk(sk)->inet_num, hashinfo->bhash_size);
 184         head = &hashinfo->bhash[bhash];
 185         head2 = inet_bhashfn_portaddr(hashinfo, sk, net, inet_sk(sk)->inet_num);
 186
 187         spin_lock(&head->lock);
 188         tb = inet_csk(sk)->icsk_bind_hash;
 189         __sk_del_bind_node(sk);
 190         inet_csk(sk)->icsk_bind_hash = NULL;
 191         inet_sk(sk)->inet_num = 0;
 192         inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);
 193
 194         spin_lock(&head2->lock);
 195         if (inet_csk(sk)->icsk_bind2_hash) {
 196                 struct inet_bind2_bucket *tb2 = inet_csk(sk)->icsk_bind2_hash;
 197
 198                 __sk_del_bind2_node(sk);
 199                 inet_csk(sk)->icsk_bind2_hash = NULL;
 200                 inet_bind2_bucket_destroy(hashinfo->bind2_bucket_cachep, tb2);
 201         }
 202         spin_unlock(&head2->lock);
 203
 204         spin_unlock(&head->lock);
 205 }
 206
 207 void inet_put_port(struct sock *sk)
 208 {
 209         local_bh_disable();
 210         __inet_put_port(sk);
 211         local_bh_enable();
 212 }
 213 EXPORT_SYMBOL(inet_put_port);
 214
 215 int __inet_inherit_port(const struct sock *sk, struct sock *child)
 216 {
 217         struct inet_hashinfo *table = tcp_or_dccp_get_hashinfo(sk);
 218         unsigned short port = inet_sk(child)->inet_num;
 219         struct inet_bind_hashbucket *head, *head2;
 220         bool created_inet_bind_bucket = false;
 221         struct net *net = sock_net(sk);
 222         bool update_fastreuse = false;
 223         struct inet_bind2_bucket *tb2;
 224         struct inet_bind_bucket *tb;
 225         int bhash, l3mdev;
 226
 227         bhash = inet_bhashfn(net, port, table->bhash_size);
 228         head = &table->bhash[bhash];
 229         head2 = inet_bhashfn_portaddr(table, child, net, port);
 230
 231         spin_lock(&head->lock);
 232         spin_lock(&head2->lock);
 233         tb = inet_csk(sk)->icsk_bind_hash;
 234         tb2 = inet_csk(sk)->icsk_bind2_hash;
 235         if (unlikely(!tb || !tb2)) {
 236                 spin_unlock(&head2->lock);
 237                 spin_unlock(&head->lock);
 238                 return -ENOENT;
 239         }
 240         if (tb->port != port) {
 241                 l3mdev = inet_sk_bound_l3mdev(sk);
 242
 243                 /* NOTE: using tproxy and redirecting skbs to a proxy
 244                  * on a different listener port breaks the assumption
 245                  * that the listener socket's icsk_bind_hash is the same
 246                  * as that of the child socket. We have to look up or
 247                  * create a new bind bucket for the child here. */
 248                 inet_bind_bucket_for_each(tb, &head->chain) {
 249                         if (inet_bind_bucket_match(tb, net, port, l3mdev))
 250                                 break;
 251                 }
 252                 if (!tb) {
 253                         tb = inet_bind_bucket_create(table->bind_bucket_cachep,
 254                                                      net, head, port, l3mdev);
 255                         if (!tb) {
 256                                 spin_unlock(&head2->lock);
 257                                 spin_unlock(&head->lock);
 258                                 return -ENOMEM;
 259                         }
 260                         created_inet_bind_bucket = true;
 261                 }
 262                 update_fastreuse = true;
 263
 264                 goto bhash2_find;
 265         } else if (!inet_bind2_bucket_addr_match(tb2, child)) {
 266                 l3mdev = inet_sk_bound_l3mdev(sk);
 267
 268 bhash2_find:
 269                 tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, child);
 270                 if (!tb2) {
 271                         tb2 = inet_bind2_bucket_create(table->bind2_bucket_cachep,
 272                                                        net, head2, port,
 273                                                        l3mdev, child);
 274                         if (!tb2)
 275                                 goto error;
 276                 }
 277         }
 278         if (update_fastreuse)
 279                 inet_csk_update_fastreuse(tb, child);
 280         inet_bind_hash(child, tb, tb2, port);
 281         spin_unlock(&head2->lock);
 282         spin_unlock(&head->lock);
 283
 284         return 0;
 285
 286 error:
 287         if (created_inet_bind_bucket)
 288                 inet_bind_bucket_destroy(table->bind_bucket_cachep, tb);
 289         spin_unlock(&head2->lock);
 290         spin_unlock(&head->lock);
 291         return -ENOMEM;
 292 }
 293 EXPORT_SYMBOL_GPL(__inet_inherit_port);
 294
 295 static struct inet_listen_hashbucket *
 296 inet_lhash2_bucket_sk(struct inet_hashinfo *h, struct sock *sk)
 297 {
 298         u32 hash;
 299
 300 #if IS_ENABLED(CONFIG_IPV6)
 301         if (sk->sk_family == AF_INET6)
 302                 hash = ipv6_portaddr_hash(sock_net(sk),
 303                                           &sk->sk_v6_rcv_saddr,
 304                                           inet_sk(sk)->inet_num);
 305         else
 306 #endif
 307                 hash = ipv4_portaddr_hash(sock_net(sk),
 308                                           inet_sk(sk)->inet_rcv_saddr,
 309                                           inet_sk(sk)->inet_num);
 310         return inet_lhash2_bucket(h, hash);
 311 }
 312
 313 static inline int compute_score(struct sock *sk, struct net *net,
 314                                 const unsigned short hnum, const __be32 daddr,
 315                                 const int dif, const int sdif)
 316 {
 317         int score = -1;
 318
 319         if (net_eq(sock_net(sk), net) && sk->sk_num == hnum &&
 320                         !ipv6_only_sock(sk)) {
 321                 if (sk->sk_rcv_saddr != daddr)
 322                         return -1;
 323
 324                 if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
 325                         return -1;
 326                 score =  sk->sk_bound_dev_if ? 2 : 1;
 327
 328                 if (sk->sk_family == PF_INET)
 329                         score++;
 330                 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 331                         score++;
 332         }
 333         return score;
 334 }
 335
 336 INDIRECT_CALLABLE_DECLARE(inet_ehashfn_t udp_ehashfn);
 337
 338 struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
 339                                    struct sk_buff *skb, int doff,
 340                                    __be32 saddr, __be16 sport,
 341                                    __be32 daddr, unsigned short hnum,
 342                                    inet_ehashfn_t *ehashfn)
 343 {
 344         struct sock *reuse_sk = NULL;
 345         u32 phash;
 346
 347         if (sk->sk_reuseport) {
 348                 phash = INDIRECT_CALL_2(ehashfn, udp_ehashfn, inet_ehashfn,
 349                                         net, daddr, hnum, saddr, sport);
 350                 reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
 351         }
 352         return reuse_sk;
 353 }
 354 EXPORT_SYMBOL_GPL(inet_lookup_reuseport);
 355
 356 /*
 357  * Here are some nice properties to exploit here. The BSD API
 358  * does not allow a listening sock to specify the remote port nor the
 359  * remote address for the connection. So always assume those are both
 360  * wildcarded during the search since they can never be otherwise.
 361  */
 362
 363 /* called with rcu_read_lock() : No refcount taken on the socket */
 364 static struct sock *inet_lhash2_lookup(struct net *net,
 365                                 struct inet_listen_hashbucket *ilb2,
 366                                 struct sk_buff *skb, int doff,
 367                                 const __be32 saddr, __be16 sport,
 368                                 const __be32 daddr, const unsigned short hnum,
 369                                 const int dif, const int sdif)
 370 {
 371         struct sock *sk, *result = NULL;
 372         struct hlist_nulls_node *node;
 373         int score, hiscore = 0;
 374
 375         sk_nulls_for_each_rcu(sk, node, &ilb2->nulls_head) {
 376                 score = compute_score(sk, net, hnum, daddr, dif, sdif);
 377                 if (score > hiscore) {
 378                         result = inet_lookup_reuseport(net, sk, skb, doff,
 379                                                        saddr, sport, daddr, hnum, inet_ehashfn);
 380                         if (result)
 381                                 return result;
 382
 383                         result = sk;
 384                         hiscore = score;
 385                 }
 386         }
 387
 388         return result;
 389 }
 390
 391 static inline struct sock *inet_lookup_run_bpf(struct net *net,
 392                                                struct inet_hashinfo *hashinfo,
 393                                                struct sk_buff *skb, int doff,
 394                                                __be32 saddr, __be16 sport,
 395                                                __be32 daddr, u16 hnum, const int dif)
 396 {
 397         struct sock *sk, *reuse_sk;
 398         bool no_reuseport;
 399
 400         if (hashinfo != net->ipv4.tcp_death_row.hashinfo)
 401                 return NULL; /* only TCP is supported */
 402
 403         no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_TCP, saddr, sport,
 404                                             daddr, hnum, dif, &sk);
 405         if (no_reuseport || IS_ERR_OR_NULL(sk))
 406                 return sk;
 407
 408         reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum,
 409                                          inet_ehashfn);
 410         if (reuse_sk)
 411                 sk = reuse_sk;
 412         return sk;
 413 }
 414
 415 struct sock *__inet_lookup_listener(struct net *net,
 416                                     struct inet_hashinfo *hashinfo,
 417                                     struct sk_buff *skb, int doff,
 418                                     const __be32 saddr, __be16 sport,
 419                                     const __be32 daddr, const unsigned short hnum,
 420                                     const int dif, const int sdif)
 421 {
 422         struct inet_listen_hashbucket *ilb2;
 423         struct sock *result = NULL;
 424         unsigned int hash2;
 425
 426         /* Lookup redirect from BPF */
 427         if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
 428                 result = inet_lookup_run_bpf(net, hashinfo, skb, doff,
 429                                              saddr, sport, daddr, hnum, dif);
 430                 if (result)
 431                         goto done;
 432         }
 433
 434         hash2 = ipv4_portaddr_hash(net, daddr, hnum);
 435         ilb2 = inet_lhash2_bucket(hashinfo, hash2);
 436
 437         result = inet_lhash2_lookup(net, ilb2, skb, doff,
 438                                     saddr, sport, daddr, hnum,
 439                                     dif, sdif);
 440         if (result)
 441                 goto done;
 442
 443         /* Lookup lhash2 with INADDR_ANY */
 444         hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
 445         ilb2 = inet_lhash2_bucket(hashinfo, hash2);
 446
 447         result = inet_lhash2_lookup(net, ilb2, skb, doff,
 448                                     saddr, sport, htonl(INADDR_ANY), hnum,
 449                                     dif, sdif);
 450 done:
 451         if (IS_ERR(result))
 452                 return NULL;
 453         return result;
 454 }
 455 EXPORT_SYMBOL_GPL(__inet_lookup_listener);
 456
 457 /* All sockets share common refcount, but have different destructors */
 458 void sock_gen_put(struct sock *sk)
 459 {
 460         if (!refcount_dec_and_test(&sk->sk_refcnt))
 461                 return;
 462
 463         if (sk->sk_state == TCP_TIME_WAIT)
 464                 inet_twsk_free(inet_twsk(sk));
 465         else if (sk->sk_state == TCP_NEW_SYN_RECV)
 466                 reqsk_free(inet_reqsk(sk));
 467         else
 468                 sk_free(sk);
 469 }
 470 EXPORT_SYMBOL_GPL(sock_gen_put);
 471
 472 void sock_edemux(struct sk_buff *skb)
 473 {
 474         sock_gen_put(skb->sk);
 475 }
 476 EXPORT_SYMBOL(sock_edemux);
 477
 478 struct sock *__inet_lookup_established(struct net *net,
 479                                   struct inet_hashinfo *hashinfo,
 480                                   const __be32 saddr, const __be16 sport,
 481                                   const __be32 daddr, const u16 hnum,
 482                                   const int dif, const int sdif)
 483 {
 484         INET_ADDR_COOKIE(acookie, saddr, daddr);
 485         const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
 486         struct sock *sk;
 487         const struct hlist_nulls_node *node;
 488         /* Optimize here for direct hit, only listening connections can
 489          * have wildcards anyways.
 490          */
 491         unsigned int hash = inet_ehashfn(net, daddr, hnum, saddr, sport);
 492         unsigned int slot = hash & hashinfo->ehash_mask;
 493         struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
 494
 495 begin:
 496         sk_nulls_for_each_rcu(sk, node, &head->chain) {
 497                 if (sk->sk_hash != hash)
 498                         continue;
 499                 if (likely(inet_match(net, sk, acookie, ports, dif, sdif))) {
 500                         if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
 501                                 goto out;
 502                         if (unlikely(!inet_match(net, sk, acookie,
 503                                                  ports, dif, sdif))) {
 504                                 sock_gen_put(sk);
 505                                 goto begin;
 506                         }
 507                         goto found;
 508                 }
 509         }
 510         /*
 511          * if the nulls value we got at the end of this lookup is
 512          * not the expected one, we must restart lookup.
 513          * We probably met an item that was moved to another chain.
 514          */
 515         if (get_nulls_value(node) != slot)
 516                 goto begin;
 517 out:
 518         sk = NULL;
 519 found:
 520         return sk;
 521 }
 522 EXPORT_SYMBOL_GPL(__inet_lookup_established);
 523
 524 /* called with local bh disabled */
 525 static int __inet_check_established(struct inet_timewait_death_row *death_row,
 526                                     struct sock *sk, __u16 lport,
 527                                     struct inet_timewait_sock **twp)
 528 {
 529         struct inet_hashinfo *hinfo = death_row->hashinfo;
 530         struct inet_sock *inet = inet_sk(sk);
 531         __be32 daddr = inet->inet_rcv_saddr;
 532         __be32 saddr = inet->inet_daddr;
 533         int dif = sk->sk_bound_dev_if;
 534         struct net *net = sock_net(sk);
 535         int sdif = l3mdev_master_ifindex_by_index(net, dif);
 536         INET_ADDR_COOKIE(acookie, saddr, daddr);
 537         const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
 538         unsigned int hash = inet_ehashfn(net, daddr, lport,
 539                                          saddr, inet->inet_dport);
 540         struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
 541         spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
 542         struct sock *sk2;
 543         const struct hlist_nulls_node *node;
 544         struct inet_timewait_sock *tw = NULL;
 545
 546         spin_lock(lock);
 547
 548         sk_nulls_for_each(sk2, node, &head->chain) {
 549                 if (sk2->sk_hash != hash)
 550                         continue;
 551
 552                 if (likely(inet_match(net, sk2, acookie, ports, dif, sdif))) {
 553                         if (sk2->sk_state == TCP_TIME_WAIT) {
 554                                 tw = inet_twsk(sk2);
 555                                 if (twsk_unique(sk, sk2, twp))
 556                                         break;
 557                         }
 558                         goto not_unique;
 559                 }
 560         }
 561
 562         /* Must record num and sport now. Otherwise we will see
 563          * in hash table socket with a funny identity.
 564          */
 565         inet->inet_num = lport;
 566         inet->inet_sport = htons(lport);
 567         sk->sk_hash = hash;
 568         WARN_ON(!sk_unhashed(sk));
 569         __sk_nulls_add_node_rcu(sk, &head->chain);
 570         if (tw) {
 571                 sk_nulls_del_node_init_rcu((struct sock *)tw);
 572                 __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
 573         }
 574         spin_unlock(lock);
 575         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 576
 577         if (twp) {
 578                 *twp = tw;
 579         } else if (tw) {
 580                 /* Silly. Should hash-dance instead... */
 581                 inet_twsk_deschedule_put(tw);
 582         }
 583         return 0;
 584
 585 not_unique:
 586         spin_unlock(lock);
 587         return -EADDRNOTAVAIL;
 588 }
 589
 590 static u64 inet_sk_port_offset(const struct sock *sk)
 591 {
 592         const struct inet_sock *inet = inet_sk(sk);
 593
 594         return secure_ipv4_port_ephemeral(inet->inet_rcv_saddr,
 595                                           inet->inet_daddr,
 596                                           inet->inet_dport);
 597 }
 598
 599 /* Searches for an exsiting socket in the ehash bucket list.
 600  * Returns true if found, false otherwise.
 601  */
 602 static bool inet_ehash_lookup_by_sk(struct sock *sk,
 603                                     struct hlist_nulls_head *list)
 604 {
 605         const __portpair ports = INET_COMBINED_PORTS(sk->sk_dport, sk->sk_num);
 606         const int sdif = sk->sk_bound_dev_if;
 607         const int dif = sk->sk_bound_dev_if;
 608         const struct hlist_nulls_node *node;
 609         struct net *net = sock_net(sk);
 610         struct sock *esk;
 611
 612         INET_ADDR_COOKIE(acookie, sk->sk_daddr, sk->sk_rcv_saddr);
 613
 614         sk_nulls_for_each_rcu(esk, node, list) {
 615                 if (esk->sk_hash != sk->sk_hash)
 616                         continue;
 617                 if (sk->sk_family == AF_INET) {
 618                         if (unlikely(inet_match(net, esk, acookie,
 619                                                 ports, dif, sdif))) {
 620                                 return true;
 621                         }
 622                 }
 623 #if IS_ENABLED(CONFIG_IPV6)
 624                 else if (sk->sk_family == AF_INET6) {
 625                         if (unlikely(inet6_match(net, esk,
 626                                                  &sk->sk_v6_daddr,
 627                                                  &sk->sk_v6_rcv_saddr,
 628                                                  ports, dif, sdif))) {
 629                                 return true;
 630                         }
 631                 }
 632 #endif
 633         }
 634         return false;
 635 }
 636
 637 /* Insert a socket into ehash, and eventually remove another one
 638  * (The another one can be a SYN_RECV or TIMEWAIT)
 639  * If an existing socket already exists, socket sk is not inserted,
 640  * and sets found_dup_sk parameter to true.
 641  */
 642 bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 643 {
 644         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 645         struct inet_ehash_bucket *head;
 646         struct hlist_nulls_head *list;
 647         spinlock_t *lock;
 648         bool ret = true;
 649
 650         WARN_ON_ONCE(!sk_unhashed(sk));
 651
 652         sk->sk_hash = sk_ehashfn(sk);
 653         head = inet_ehash_bucket(hashinfo, sk->sk_hash);
 654         list = &head->chain;
 655         lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 656
 657         spin_lock(lock);
 658         if (osk) {
 659                 WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
 660                 ret = sk_nulls_del_node_init_rcu(osk);
 661         } else if (found_dup_sk) {
 662                 *found_dup_sk = inet_ehash_lookup_by_sk(sk, list);
 663                 if (*found_dup_sk)
 664                         ret = false;
 665         }
 666
 667         if (ret)
 668                 __sk_nulls_add_node_rcu(sk, list);
 669
 670         spin_unlock(lock);
 671
 672         return ret;
 673 }
 674
 675 bool inet_ehash_nolisten(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 676 {
 677         bool ok = inet_ehash_insert(sk, osk, found_dup_sk);
 678
 679         if (ok) {
 680                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 681         } else {
 682                 this_cpu_inc(*sk->sk_prot->orphan_count);
 683                 inet_sk_set_state(sk, TCP_CLOSE);
 684                 sock_set_flag(sk, SOCK_DEAD);
 685                 inet_csk_destroy_sock(sk);
 686         }
 687         return ok;
 688 }
 689 EXPORT_SYMBOL_GPL(inet_ehash_nolisten);
 690
 691 static int inet_reuseport_add_sock(struct sock *sk,
 692                                    struct inet_listen_hashbucket *ilb)
 693 {
 694         struct inet_bind_bucket *tb = inet_csk(sk)->icsk_bind_hash;
 695         const struct hlist_nulls_node *node;
 696         struct sock *sk2;
 697         kuid_t uid = sock_i_uid(sk);
 698
 699         sk_nulls_for_each_rcu(sk2, node, &ilb->nulls_head) {
 700                 if (sk2 != sk &&
 701                     sk2->sk_family == sk->sk_family &&
 702                     ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
 703                     sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
 704                     inet_csk(sk2)->icsk_bind_hash == tb &&
 705                     sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
 706                     inet_rcv_saddr_equal(sk, sk2, false))
 707                         return reuseport_add_sock(sk, sk2,
 708                                                   inet_rcv_saddr_any(sk));
 709         }
 710
 711         return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
 712 }
 713
 714 int __inet_hash(struct sock *sk, struct sock *osk)
 715 {
 716         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 717         struct inet_listen_hashbucket *ilb2;
 718         int err = 0;
 719
 720         if (sk->sk_state != TCP_LISTEN) {
 721                 local_bh_disable();
 722                 inet_ehash_nolisten(sk, osk, NULL);
 723                 local_bh_enable();
 724                 return 0;
 725         }
 726         WARN_ON(!sk_unhashed(sk));
 727         ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 728
 729         spin_lock(&ilb2->lock);
 730         if (sk->sk_reuseport) {
 731                 err = inet_reuseport_add_sock(sk, ilb2);
 732                 if (err)
 733                         goto unlock;
 734         }
 735         if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 736                 sk->sk_family == AF_INET6)
 737                 __sk_nulls_add_node_tail_rcu(sk, &ilb2->nulls_head);
 738         else
 739                 __sk_nulls_add_node_rcu(sk, &ilb2->nulls_head);
 740         sock_set_flag(sk, SOCK_RCU_FREE);
 741         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 742 unlock:
 743         spin_unlock(&ilb2->lock);
 744
 745         return err;
 746 }
 747 EXPORT_SYMBOL(__inet_hash);
 748
 749 int inet_hash(struct sock *sk)
 750 {
 751         int err = 0;
 752
 753         if (sk->sk_state != TCP_CLOSE)
 754                 err = __inet_hash(sk, NULL);
 755
 756         return err;
 757 }
 758 EXPORT_SYMBOL_GPL(inet_hash);
 759
 760 void inet_unhash(struct sock *sk)
 761 {
 762         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 763
 764         if (sk_unhashed(sk))
 765                 return;
 766
 767         if (sk->sk_state == TCP_LISTEN) {
 768                 struct inet_listen_hashbucket *ilb2;
 769
 770                 ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 771                 /* Don't disable bottom halves while acquiring the lock to
 772                  * avoid circular locking dependency on PREEMPT_RT.
 773                  */
 774                 spin_lock(&ilb2->lock);
 775                 if (sk_unhashed(sk)) {
 776                         spin_unlock(&ilb2->lock);
 777                         return;
 778                 }
 779
 780                 if (rcu_access_pointer(sk->sk_reuseport_cb))
 781                         reuseport_stop_listen_sock(sk);
 782
 783                 __sk_nulls_del_node_init_rcu(sk);
 784                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 785                 spin_unlock(&ilb2->lock);
 786         } else {
 787                 spinlock_t *lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 788
 789                 spin_lock_bh(lock);
 790                 if (sk_unhashed(sk)) {
 791                         spin_unlock_bh(lock);
 792                         return;
 793                 }
 794                 __sk_nulls_del_node_init_rcu(sk);
 795                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 796                 spin_unlock_bh(lock);
 797         }
 798 }
 799 EXPORT_SYMBOL_GPL(inet_unhash);
 800
 801 static bool inet_bind2_bucket_match(const struct inet_bind2_bucket *tb,
 802                                     const struct net *net, unsigned short port,
 803                                     int l3mdev, const struct sock *sk)
 804 {
 805 #if IS_ENABLED(CONFIG_IPV6)
 806         if (sk->sk_family != tb->family)
 807                 return false;
 808
 809         if (sk->sk_family == AF_INET6)
 810                 return net_eq(ib2_net(tb), net) && tb->port == port &&
 811                         tb->l3mdev == l3mdev &&
 812                         ipv6_addr_equal(&tb->v6_rcv_saddr, &sk->sk_v6_rcv_saddr);
 813         else
 814 #endif
 815                 return net_eq(ib2_net(tb), net) && tb->port == port &&
 816                         tb->l3mdev == l3mdev && tb->rcv_saddr == sk->sk_rcv_saddr;
 817 }
 818
 819 bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const struct net *net,
 820                                       unsigned short port, int l3mdev, const struct sock *sk)
 821 {
 822 #if IS_ENABLED(CONFIG_IPV6)
 823         if (sk->sk_family != tb->family) {
 824                 if (sk->sk_family == AF_INET)
 825                         return net_eq(ib2_net(tb), net) && tb->port == port &&
 826                                 tb->l3mdev == l3mdev &&
 827                                 ipv6_addr_any(&tb->v6_rcv_saddr);
 828
 829                 return false;
 830         }
 831
 832         if (sk->sk_family == AF_INET6)
 833                 return net_eq(ib2_net(tb), net) && tb->port == port &&
 834                         tb->l3mdev == l3mdev &&
 835                         ipv6_addr_any(&tb->v6_rcv_saddr);
 836         else
 837 #endif
 838                 return net_eq(ib2_net(tb), net) && tb->port == port &&
 839                         tb->l3mdev == l3mdev && tb->rcv_saddr == 0;
 840 }
 841
 842 /* The socket's bhash2 hashbucket spinlock must be held when this is called */
 843 struct inet_bind2_bucket *
 844 inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, const struct net *net,
 845                        unsigned short port, int l3mdev, const struct sock *sk)
 846 {
 847         struct inet_bind2_bucket *bhash2 = NULL;
 848
 849         inet_bind_bucket_for_each(bhash2, &head->chain)
 850                 if (inet_bind2_bucket_match(bhash2, net, port, l3mdev, sk))
 851                         break;
 852
 853         return bhash2;
 854 }
 855
 856 struct inet_bind_hashbucket *
 857 inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port)
 858 {
 859         struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 860         u32 hash;
 861
 862 #if IS_ENABLED(CONFIG_IPV6)
 863         if (sk->sk_family == AF_INET6)
 864                 hash = ipv6_portaddr_hash(net, &in6addr_any, port);
 865         else
 866 #endif
 867                 hash = ipv4_portaddr_hash(net, 0, port);
 868
 869         return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
 870 }
 871
 872 static void inet_update_saddr(struct sock *sk, void *saddr, int family)
 873 {
 874         if (family == AF_INET) {
 875                 inet_sk(sk)->inet_saddr = *(__be32 *)saddr;
 876                 sk_rcv_saddr_set(sk, inet_sk(sk)->inet_saddr);
 877         }
 878 #if IS_ENABLED(CONFIG_IPV6)
 879         else {
 880                 sk->sk_v6_rcv_saddr = *(struct in6_addr *)saddr;
 881         }
 882 #endif
 883 }
 884
 885 static int __inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family, bool reset)
 886 {
 887         struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 888         struct inet_bind_hashbucket *head, *head2;
 889         struct inet_bind2_bucket *tb2, *new_tb2;
 890         int l3mdev = inet_sk_bound_l3mdev(sk);
 891         int port = inet_sk(sk)->inet_num;
 892         struct net *net = sock_net(sk);
 893         int bhash;
 894
 895         if (!inet_csk(sk)->icsk_bind2_hash) {
 896                 /* Not bind()ed before. */
 897                 if (reset)
 898                         inet_reset_saddr(sk);
 899                 else
 900                         inet_update_saddr(sk, saddr, family);
 901
 902                 return 0;
 903         }
 904
 905         /* Allocate a bind2 bucket ahead of time to avoid permanently putting
 906          * the bhash2 table in an inconsistent state if a new tb2 bucket
 907          * allocation fails.
 908          */
 909         new_tb2 = kmem_cache_alloc(hinfo->bind2_bucket_cachep, GFP_ATOMIC);
 910         if (!new_tb2) {
 911                 if (reset) {
 912                         /* The (INADDR_ANY, port) bucket might have already
 913                          * been freed, then we cannot fixup icsk_bind2_hash,
 914                          * so we give up and unlink sk from bhash/bhash2 not
 915                          * to leave inconsistency in bhash2.
 916                          */
 917                         inet_put_port(sk);
 918                         inet_reset_saddr(sk);
 919                 }
 920
 921                 return -ENOMEM;
 922         }
 923
 924         bhash = inet_bhashfn(net, port, hinfo->bhash_size);
 925         head = &hinfo->bhash[bhash];
 926         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 927
 928         /* If we change saddr locklessly, another thread
 929          * iterating over bhash might see corrupted address.
 930          */
 931         spin_lock_bh(&head->lock);
 932
 933         spin_lock(&head2->lock);
 934         __sk_del_bind2_node(sk);
 935         inet_bind2_bucket_destroy(hinfo->bind2_bucket_cachep, inet_csk(sk)->icsk_bind2_hash);
 936         spin_unlock(&head2->lock);
 937
 938         if (reset)
 939                 inet_reset_saddr(sk);
 940         else
 941                 inet_update_saddr(sk, saddr, family);
 942
 943         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 944
 945         spin_lock(&head2->lock);
 946         tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
 947         if (!tb2) {
 948                 tb2 = new_tb2;
 949                 inet_bind2_bucket_init(tb2, net, head2, port, l3mdev, sk);
 950         }
 951         sk_add_bind2_node(sk, &tb2->owners);
 952         inet_csk(sk)->icsk_bind2_hash = tb2;
 953         spin_unlock(&head2->lock);
 954
 955         spin_unlock_bh(&head->lock);
 956
 957         if (tb2 != new_tb2)
 958                 kmem_cache_free(hinfo->bind2_bucket_cachep, new_tb2);
 959
 960         return 0;
 961 }
 962
 963 int inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family)
 964 {
 965         return __inet_bhash2_update_saddr(sk, saddr, family, false);
 966 }
 967 EXPORT_SYMBOL_GPL(inet_bhash2_update_saddr);
 968
 969 void inet_bhash2_reset_saddr(struct sock *sk)
 970 {
 971         if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
 972                 __inet_bhash2_update_saddr(sk, NULL, 0, true);
 973 }
 974 EXPORT_SYMBOL_GPL(inet_bhash2_reset_saddr);
 975
 976 /* RFC 6056 3.3.4.  Algorithm 4: Double-Hash Port Selection Algorithm
 977  * Note that we use 32bit integers (vs RFC 'short integers')
 978  * because 2^16 is not a multiple of num_ephemeral and this
 979  * property might be used by clever attacker.
 980  *
 981  * RFC claims using TABLE_LENGTH=10 buckets gives an improvement, though
 982  * attacks were since demonstrated, thus we use 65536 by default instead
 983  * to really give more isolation and privacy, at the expense of 256kB
 984  * of kernel memory.
 985  */
 986 #define INET_TABLE_PERTURB_SIZE (1 << CONFIG_INET_TABLE_PERTURB_ORDER)
 987 static u32 *table_perturb;
 988
 989 int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 990                 struct sock *sk, u64 port_offset,
 991                 int (*check_established)(struct inet_timewait_death_row *,
 992                         struct sock *, __u16, struct inet_timewait_sock **))
 993 {
 994         struct inet_hashinfo *hinfo = death_row->hashinfo;
 995         struct inet_bind_hashbucket *head, *head2;
 996         struct inet_timewait_sock *tw = NULL;
 997         int port = inet_sk(sk)->inet_num;
 998         struct net *net = sock_net(sk);
 999         struct inet_bind2_bucket *tb2;
1000         struct inet_bind_bucket *tb;
1001         bool tb_created = false;
1002         u32 remaining, offset;
1003         int ret, i, low, high;
1004         int l3mdev;
1005         u32 index;
1006
1007         if (port) {
1008                 local_bh_disable();
1009                 ret = check_established(death_row, sk, port, NULL);
1010                 local_bh_enable();
1011                 return ret;
1012         }
1013
1014         l3mdev = inet_sk_bound_l3mdev(sk);
1015
1016         inet_sk_get_local_port_range(sk, &low, &high);
1017         high++; /* [32768, 60999] -> [32768, 61000[ */
1018         remaining = high - low;
1019         if (likely(remaining > 1))
1020                 remaining &= ~1U;
1021
1022         get_random_sleepable_once(table_perturb,
1023                                   INET_TABLE_PERTURB_SIZE * sizeof(*table_perturb));
1024         index = port_offset & (INET_TABLE_PERTURB_SIZE - 1);
1025
1026         offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32);
1027         offset %= remaining;
1028
1029         /* In first pass we try ports of @low parity.
1030          * inet_csk_get_port() does the opposite choice.
1031          */
1032         offset &= ~1U;
1033 other_parity_scan:
1034         port = low + offset;
1035         for (i = 0; i < remaining; i += 2, port += 2) {
1036                 if (unlikely(port >= high))
1037                         port -= remaining;
1038                 if (inet_is_local_reserved_port(net, port))
1039                         continue;
1040                 head = &hinfo->bhash[inet_bhashfn(net, port,
1041                                                   hinfo->bhash_size)];
1042                 spin_lock_bh(&head->lock);
1043
1044                 /* Does not bother with rcv_saddr checks, because
1045                  * the established check is already unique enough.
1046                  */
1047                 inet_bind_bucket_for_each(tb, &head->chain) {
1048                         if (inet_bind_bucket_match(tb, net, port, l3mdev)) {
1049                                 if (tb->fastreuse >= 0 ||
1050                                     tb->fastreuseport >= 0)
1051                                         goto next_port;
1052                                 WARN_ON(hlist_empty(&tb->owners));
1053                                 if (!check_established(death_row, sk,
1054                                                        port, &tw))
1055                                         goto ok;
1056                                 goto next_port;
1057                         }
1058                 }
1059
1060                 tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
1061                                              net, head, port, l3mdev);
1062                 if (!tb) {
1063                         spin_unlock_bh(&head->lock);
1064                         return -ENOMEM;
1065                 }
1066                 tb_created = true;
1067                 tb->fastreuse = -1;
1068                 tb->fastreuseport = -1;
1069                 goto ok;
1070 next_port:
1071                 spin_unlock_bh(&head->lock);
1072                 cond_resched();
1073         }
1074
1075         offset++;
1076         if ((offset & 1) && remaining > 1)
1077                 goto other_parity_scan;
1078
1079         return -EADDRNOTAVAIL;
1080
1081 ok:
1082         /* Find the corresponding tb2 bucket since we need to
1083          * add the socket to the bhash2 table as well
1084          */
1085         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
1086         spin_lock(&head2->lock);
1087
1088         tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
1089         if (!tb2) {
1090                 tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep, net,
1091                                                head2, port, l3mdev, sk);
1092                 if (!tb2)
1093                         goto error;
1094         }
1095
1096         /* Here we want to add a little bit of randomness to the next source
1097          * port that will be chosen. We use a max() with a random here so that
1098          * on low contention the randomness is maximal and on high contention
1099          * it may be inexistent.
1100          */
1101         i = max_t(int, i, get_random_u32_below(8) * 2);
1102         WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + 2);
1103
1104         /* Head lock still held and bh's disabled */
1105         inet_bind_hash(sk, tb, tb2, port);
1106
1107         if (sk_unhashed(sk)) {
1108                 inet_sk(sk)->inet_sport = htons(port);
1109                 inet_ehash_nolisten(sk, (struct sock *)tw, NULL);
1110         }
1111         if (tw)
1112                 inet_twsk_bind_unhash(tw, hinfo);
1113
1114         spin_unlock(&head2->lock);
1115         spin_unlock(&head->lock);
1116
1117         if (tw)
1118                 inet_twsk_deschedule_put(tw);
1119         local_bh_enable();
1120         return 0;
1121
1122 error:
1123         spin_unlock(&head2->lock);
1124         if (tb_created)
1125                 inet_bind_bucket_destroy(hinfo->bind_bucket_cachep, tb);
1126         spin_unlock_bh(&head->lock);
1127         return -ENOMEM;
1128 }
1129
1130 /*
1131  * Bind a port for a connect operation and hash it.
1132  */
1133 int inet_hash_connect(struct inet_timewait_death_row *death_row,
1134                       struct sock *sk)
1135 {
1136         u64 port_offset = 0;
1137
1138         if (!inet_sk(sk)->inet_num)
1139                 port_offset = inet_sk_port_offset(sk);
1140         return __inet_hash_connect(death_row, sk, port_offset,
1141                                    __inet_check_established);
1142 }
1143 EXPORT_SYMBOL_GPL(inet_hash_connect);
1144
1145 static void init_hashinfo_lhash2(struct inet_hashinfo *h)
1146 {
1147         int i;
1148
1149         for (i = 0; i <= h->lhash2_mask; i++) {
1150                 spin_lock_init(&h->lhash2[i].lock);
1151                 INIT_HLIST_NULLS_HEAD(&h->lhash2[i].nulls_head,
1152                                       i + LISTENING_NULLS_BASE);
1153         }
1154 }
1155
1156 void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
1157                                 unsigned long numentries, int scale,
1158                                 unsigned long low_limit,
1159                                 unsigned long high_limit)
1160 {
1161         h->lhash2 = alloc_large_system_hash(name,
1162                                             sizeof(*h->lhash2),
1163                                             numentries,
1164                                             scale,
1165                                             0,
1166                                             NULL,
1167                                             &h->lhash2_mask,
1168                                             low_limit,
1169                                             high_limit);
1170         init_hashinfo_lhash2(h);
1171
1172         /* this one is used for source ports of outgoing connections */
1173         table_perturb = alloc_large_system_hash("Table-perturb",
1174                                                 sizeof(*table_perturb),
1175                                                 INET_TABLE_PERTURB_SIZE,
1176                                                 0, 0, NULL, NULL,
1177                                                 INET_TABLE_PERTURB_SIZE,
1178                                                 INET_TABLE_PERTURB_SIZE);
1179 }
1180
1181 int inet_hashinfo2_init_mod(struct inet_hashinfo *h)
1182 {
1183         h->lhash2 = kmalloc_array(INET_LHTABLE_SIZE, sizeof(*h->lhash2), GFP_KERNEL);
1184         if (!h->lhash2)
1185                 return -ENOMEM;
1186
1187         h->lhash2_mask = INET_LHTABLE_SIZE - 1;
1188         /* INET_LHTABLE_SIZE must be a power of 2 */
1189         BUG_ON(INET_LHTABLE_SIZE & h->lhash2_mask);
1190
1191         init_hashinfo_lhash2(h);
1192         return 0;
1193 }
1194 EXPORT_SYMBOL_GPL(inet_hashinfo2_init_mod);
1195
1196 int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
1197 {
1198         unsigned int locksz = sizeof(spinlock_t);
1199         unsigned int i, nblocks = 1;
1200
1201         if (locksz != 0) {
1202                 /* allocate 2 cache lines or at least one spinlock per cpu */
1203                 nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
1204                 nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
1205
1206                 /* no more locks than number of hash buckets */
1207                 nblocks = min(nblocks, hashinfo->ehash_mask + 1);
1208
1209                 hashinfo->ehash_locks = kvmalloc_array(nblocks, locksz, GFP_KERNEL);
1210                 if (!hashinfo->ehash_locks)
1211                         return -ENOMEM;
1212
1213                 for (i = 0; i < nblocks; i++)
1214                         spin_lock_init(&hashinfo->ehash_locks[i]);
1215         }
1216         hashinfo->ehash_locks_mask = nblocks - 1;
1217         return 0;
1218 }
1219 EXPORT_SYMBOL_GPL(inet_ehash_locks_alloc);
1220
1221 struct inet_hashinfo *inet_pernet_hashinfo_alloc(struct inet_hashinfo *hashinfo,
1222                                                  unsigned int ehash_entries)
1223 {
1224         struct inet_hashinfo *new_hashinfo;
1225         int i;
1226
1227         new_hashinfo = kmemdup(hashinfo, sizeof(*hashinfo), GFP_KERNEL);
1228         if (!new_hashinfo)
1229                 goto err;
1230
1231         new_hashinfo->ehash = vmalloc_huge(ehash_entries * sizeof(struct inet_ehash_bucket),
1232                                            GFP_KERNEL_ACCOUNT);
1233         if (!new_hashinfo->ehash)
1234                 goto free_hashinfo;
1235
1236         new_hashinfo->ehash_mask = ehash_entries - 1;
1237
1238         if (inet_ehash_locks_alloc(new_hashinfo))
1239                 goto free_ehash;
1240
1241         for (i = 0; i < ehash_entries; i++)
1242                 INIT_HLIST_NULLS_HEAD(&new_hashinfo->ehash[i].chain, i);
1243
1244         new_hashinfo->pernet = true;
1245
1246         return new_hashinfo;
1247
1248 free_ehash:
1249         vfree(new_hashinfo->ehash);
1250 free_hashinfo:
1251         kfree(new_hashinfo);
1252 err:
1253         return NULL;
1254 }
1255 EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_alloc);
1256
1257 void inet_pernet_hashinfo_free(struct inet_hashinfo *hashinfo)
1258 {
1259         if (!hashinfo->pernet)
1260                 return;
1261
1262         inet_ehash_locks_free(hashinfo);
1263         vfree(hashinfo->ehash);
1264         kfree(hashinfo);
1265 }
1266 EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_free);