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 static 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
  43 /* This function handles inet_sock, but also timewait and request sockets
  44  * for IPv4/IPv6.
  45  */
  46 static u32 sk_ehashfn(const struct sock *sk)
  47 {
  48 #if IS_ENABLED(CONFIG_IPV6)
  49         if (sk->sk_family == AF_INET6 &&
  50             !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
  51                 return inet6_ehashfn(sock_net(sk),
  52                                      &sk->sk_v6_rcv_saddr, sk->sk_num,
  53                                      &sk->sk_v6_daddr, sk->sk_dport);
  54 #endif
  55         return inet_ehashfn(sock_net(sk),
  56                             sk->sk_rcv_saddr, sk->sk_num,
  57                             sk->sk_daddr, sk->sk_dport);
  58 }
  59
  60 /*
  61  * Allocate and initialize a new local port bind bucket.
  62  * The bindhash mutex for snum's hash chain must be held here.
  63  */
  64 struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
  65                                                  struct net *net,
  66                                                  struct inet_bind_hashbucket *head,
  67                                                  const unsigned short snum,
  68                                                  int l3mdev)
  69 {
  70         struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
  71
  72         if (tb) {
  73                 write_pnet(&tb->ib_net, net);
  74                 tb->l3mdev    = l3mdev;
  75                 tb->port      = snum;
  76                 tb->fastreuse = 0;
  77                 tb->fastreuseport = 0;
  78                 INIT_HLIST_HEAD(&tb->owners);
  79                 hlist_add_head(&tb->node, &head->chain);
  80         }
  81         return tb;
  82 }
  83
  84 /*
  85  * Caller must hold hashbucket lock for this tb with local BH disabled
  86  */
  87 void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket *tb)
  88 {
  89         if (hlist_empty(&tb->owners)) {
  90                 __hlist_del(&tb->node);
  91                 kmem_cache_free(cachep, tb);
  92         }
  93 }
  94
  95 bool inet_bind_bucket_match(const struct inet_bind_bucket *tb, const struct net *net,
  96                             unsigned short port, int l3mdev)
  97 {
  98         return net_eq(ib_net(tb), net) && tb->port == port &&
  99                 tb->l3mdev == l3mdev;
 100 }
 101
 102 static void inet_bind2_bucket_init(struct inet_bind2_bucket *tb,
 103                                    struct net *net,
 104                                    struct inet_bind_hashbucket *head,
 105                                    unsigned short port, int l3mdev,
 106                                    const struct sock *sk)
 107 {
 108         write_pnet(&tb->ib_net, net);
 109         tb->l3mdev    = l3mdev;
 110         tb->port      = port;
 111 #if IS_ENABLED(CONFIG_IPV6)
 112         tb->family    = sk->sk_family;
 113         if (sk->sk_family == AF_INET6)
 114                 tb->v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 115         else
 116 #endif
 117                 tb->rcv_saddr = sk->sk_rcv_saddr;
 118         INIT_HLIST_HEAD(&tb->owners);
 119         INIT_HLIST_HEAD(&tb->deathrow);
 120         hlist_add_head(&tb->node, &head->chain);
 121 }
 122
 123 struct inet_bind2_bucket *inet_bind2_bucket_create(struct kmem_cache *cachep,
 124                                                    struct net *net,
 125                                                    struct inet_bind_hashbucket *head,
 126                                                    unsigned short port,
 127                                                    int l3mdev,
 128                                                    const struct sock *sk)
 129 {
 130         struct inet_bind2_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
 131
 132         if (tb)
 133                 inet_bind2_bucket_init(tb, net, head, port, l3mdev, sk);
 134
 135         return tb;
 136 }
 137
 138 /* Caller must hold hashbucket lock for this tb with local BH disabled */
 139 void inet_bind2_bucket_destroy(struct kmem_cache *cachep, struct inet_bind2_bucket *tb)
 140 {
 141         if (hlist_empty(&tb->owners) && hlist_empty(&tb->deathrow)) {
 142                 __hlist_del(&tb->node);
 143                 kmem_cache_free(cachep, tb);
 144         }
 145 }
 146
 147 static bool inet_bind2_bucket_addr_match(const struct inet_bind2_bucket *tb2,
 148                                          const struct sock *sk)
 149 {
 150 #if IS_ENABLED(CONFIG_IPV6)
 151         if (sk->sk_family != tb2->family) {
 152                 if (sk->sk_family == AF_INET)
 153                         return ipv6_addr_v4mapped(&tb2->v6_rcv_saddr) &&
 154                                 tb2->v6_rcv_saddr.s6_addr32[3] == sk->sk_rcv_saddr;
 155
 156                 return ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr) &&
 157                         sk->sk_v6_rcv_saddr.s6_addr32[3] == tb2->rcv_saddr;
 158         }
 159
 160         if (sk->sk_family == AF_INET6)
 161                 return ipv6_addr_equal(&tb2->v6_rcv_saddr,
 162                                        &sk->sk_v6_rcv_saddr);
 163 #endif
 164         return tb2->rcv_saddr == sk->sk_rcv_saddr;
 165 }
 166
 167 void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
 168                     struct inet_bind2_bucket *tb2, unsigned short port)
 169 {
 170         inet_sk(sk)->inet_num = port;
 171         sk_add_bind_node(sk, &tb->owners);
 172         inet_csk(sk)->icsk_bind_hash = tb;
 173         sk_add_bind2_node(sk, &tb2->owners);
 174         inet_csk(sk)->icsk_bind2_hash = tb2;
 175 }
 176
 177 /*
 178  * Get rid of any references to a local port held by the given sock.
 179  */
 180 static void __inet_put_port(struct sock *sk)
 181 {
 182         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 183         struct inet_bind_hashbucket *head, *head2;
 184         struct net *net = sock_net(sk);
 185         struct inet_bind_bucket *tb;
 186         int bhash;
 187
 188         bhash = inet_bhashfn(net, inet_sk(sk)->inet_num, hashinfo->bhash_size);
 189         head = &hashinfo->bhash[bhash];
 190         head2 = inet_bhashfn_portaddr(hashinfo, sk, net, inet_sk(sk)->inet_num);
 191
 192         spin_lock(&head->lock);
 193         tb = inet_csk(sk)->icsk_bind_hash;
 194         __sk_del_bind_node(sk);
 195         inet_csk(sk)->icsk_bind_hash = NULL;
 196         inet_sk(sk)->inet_num = 0;
 197         inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);
 198
 199         spin_lock(&head2->lock);
 200         if (inet_csk(sk)->icsk_bind2_hash) {
 201                 struct inet_bind2_bucket *tb2 = inet_csk(sk)->icsk_bind2_hash;
 202
 203                 __sk_del_bind2_node(sk);
 204                 inet_csk(sk)->icsk_bind2_hash = NULL;
 205                 inet_bind2_bucket_destroy(hashinfo->bind2_bucket_cachep, tb2);
 206         }
 207         spin_unlock(&head2->lock);
 208
 209         spin_unlock(&head->lock);
 210 }
 211
 212 void inet_put_port(struct sock *sk)
 213 {
 214         local_bh_disable();
 215         __inet_put_port(sk);
 216         local_bh_enable();
 217 }
 218 EXPORT_SYMBOL(inet_put_port);
 219
 220 int __inet_inherit_port(const struct sock *sk, struct sock *child)
 221 {
 222         struct inet_hashinfo *table = tcp_or_dccp_get_hashinfo(sk);
 223         unsigned short port = inet_sk(child)->inet_num;
 224         struct inet_bind_hashbucket *head, *head2;
 225         bool created_inet_bind_bucket = false;
 226         struct net *net = sock_net(sk);
 227         bool update_fastreuse = false;
 228         struct inet_bind2_bucket *tb2;
 229         struct inet_bind_bucket *tb;
 230         int bhash, l3mdev;
 231
 232         bhash = inet_bhashfn(net, port, table->bhash_size);
 233         head = &table->bhash[bhash];
 234         head2 = inet_bhashfn_portaddr(table, child, net, port);
 235
 236         spin_lock(&head->lock);
 237         spin_lock(&head2->lock);
 238         tb = inet_csk(sk)->icsk_bind_hash;
 239         tb2 = inet_csk(sk)->icsk_bind2_hash;
 240         if (unlikely(!tb || !tb2)) {
 241                 spin_unlock(&head2->lock);
 242                 spin_unlock(&head->lock);
 243                 return -ENOENT;
 244         }
 245         if (tb->port != port) {
 246                 l3mdev = inet_sk_bound_l3mdev(sk);
 247
 248                 /* NOTE: using tproxy and redirecting skbs to a proxy
 249                  * on a different listener port breaks the assumption
 250                  * that the listener socket's icsk_bind_hash is the same
 251                  * as that of the child socket. We have to look up or
 252                  * create a new bind bucket for the child here. */
 253                 inet_bind_bucket_for_each(tb, &head->chain) {
 254                         if (inet_bind_bucket_match(tb, net, port, l3mdev))
 255                                 break;
 256                 }
 257                 if (!tb) {
 258                         tb = inet_bind_bucket_create(table->bind_bucket_cachep,
 259                                                      net, head, port, l3mdev);
 260                         if (!tb) {
 261                                 spin_unlock(&head2->lock);
 262                                 spin_unlock(&head->lock);
 263                                 return -ENOMEM;
 264                         }
 265                         created_inet_bind_bucket = true;
 266                 }
 267                 update_fastreuse = true;
 268
 269                 goto bhash2_find;
 270         } else if (!inet_bind2_bucket_addr_match(tb2, child)) {
 271                 l3mdev = inet_sk_bound_l3mdev(sk);
 272
 273 bhash2_find:
 274                 tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, child);
 275                 if (!tb2) {
 276                         tb2 = inet_bind2_bucket_create(table->bind2_bucket_cachep,
 277                                                        net, head2, port,
 278                                                        l3mdev, child);
 279                         if (!tb2)
 280                                 goto error;
 281                 }
 282         }
 283         if (update_fastreuse)
 284                 inet_csk_update_fastreuse(tb, child);
 285         inet_bind_hash(child, tb, tb2, port);
 286         spin_unlock(&head2->lock);
 287         spin_unlock(&head->lock);
 288
 289         return 0;
 290
 291 error:
 292         if (created_inet_bind_bucket)
 293                 inet_bind_bucket_destroy(table->bind_bucket_cachep, tb);
 294         spin_unlock(&head2->lock);
 295         spin_unlock(&head->lock);
 296         return -ENOMEM;
 297 }
 298 EXPORT_SYMBOL_GPL(__inet_inherit_port);
 299
 300 static struct inet_listen_hashbucket *
 301 inet_lhash2_bucket_sk(struct inet_hashinfo *h, struct sock *sk)
 302 {
 303         u32 hash;
 304
 305 #if IS_ENABLED(CONFIG_IPV6)
 306         if (sk->sk_family == AF_INET6)
 307                 hash = ipv6_portaddr_hash(sock_net(sk),
 308                                           &sk->sk_v6_rcv_saddr,
 309                                           inet_sk(sk)->inet_num);
 310         else
 311 #endif
 312                 hash = ipv4_portaddr_hash(sock_net(sk),
 313                                           inet_sk(sk)->inet_rcv_saddr,
 314                                           inet_sk(sk)->inet_num);
 315         return inet_lhash2_bucket(h, hash);
 316 }
 317
 318 static inline int compute_score(struct sock *sk, struct net *net,
 319                                 const unsigned short hnum, const __be32 daddr,
 320                                 const int dif, const int sdif)
 321 {
 322         int score = -1;
 323
 324         if (net_eq(sock_net(sk), net) && sk->sk_num == hnum &&
 325                         !ipv6_only_sock(sk)) {
 326                 if (sk->sk_rcv_saddr != daddr)
 327                         return -1;
 328
 329                 if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
 330                         return -1;
 331                 score =  sk->sk_bound_dev_if ? 2 : 1;
 332
 333                 if (sk->sk_family == PF_INET)
 334                         score++;
 335                 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 336                         score++;
 337         }
 338         return score;
 339 }
 340
 341 static inline struct sock *lookup_reuseport(struct net *net, struct sock *sk,
 342                                             struct sk_buff *skb, int doff,
 343                                             __be32 saddr, __be16 sport,
 344                                             __be32 daddr, unsigned short hnum)
 345 {
 346         struct sock *reuse_sk = NULL;
 347         u32 phash;
 348
 349         if (sk->sk_reuseport) {
 350                 phash = inet_ehashfn(net, daddr, hnum, saddr, sport);
 351                 reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
 352         }
 353         return reuse_sk;
 354 }
 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 = lookup_reuseport(net, sk, skb, doff,
 379                                                   saddr, sport, daddr, hnum);
 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 = lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
 409         if (reuse_sk)
 410                 sk = reuse_sk;
 411         return sk;
 412 }
 413
 414 struct sock *__inet_lookup_listener(struct net *net,
 415                                     struct inet_hashinfo *hashinfo,
 416                                     struct sk_buff *skb, int doff,
 417                                     const __be32 saddr, __be16 sport,
 418                                     const __be32 daddr, const unsigned short hnum,
 419                                     const int dif, const int sdif)
 420 {
 421         struct inet_listen_hashbucket *ilb2;
 422         struct sock *result = NULL;
 423         unsigned int hash2;
 424
 425         /* Lookup redirect from BPF */
 426         if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
 427                 result = inet_lookup_run_bpf(net, hashinfo, skb, doff,
 428                                              saddr, sport, daddr, hnum, dif);
 429                 if (result)
 430                         goto done;
 431         }
 432
 433         hash2 = ipv4_portaddr_hash(net, daddr, hnum);
 434         ilb2 = inet_lhash2_bucket(hashinfo, hash2);
 435
 436         result = inet_lhash2_lookup(net, ilb2, skb, doff,
 437                                     saddr, sport, daddr, hnum,
 438                                     dif, sdif);
 439         if (result)
 440                 goto done;
 441
 442         /* Lookup lhash2 with INADDR_ANY */
 443         hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
 444         ilb2 = inet_lhash2_bucket(hashinfo, hash2);
 445
 446         result = inet_lhash2_lookup(net, ilb2, skb, doff,
 447                                     saddr, sport, htonl(INADDR_ANY), hnum,
 448                                     dif, sdif);
 449 done:
 450         if (IS_ERR(result))
 451                 return NULL;
 452         return result;
 453 }
 454 EXPORT_SYMBOL_GPL(__inet_lookup_listener);
 455
 456 /* All sockets share common refcount, but have different destructors */
 457 void sock_gen_put(struct sock *sk)
 458 {
 459         if (!refcount_dec_and_test(&sk->sk_refcnt))
 460                 return;
 461
 462         if (sk->sk_state == TCP_TIME_WAIT)
 463                 inet_twsk_free(inet_twsk(sk));
 464         else if (sk->sk_state == TCP_NEW_SYN_RECV)
 465                 reqsk_free(inet_reqsk(sk));
 466         else
 467                 sk_free(sk);
 468 }
 469 EXPORT_SYMBOL_GPL(sock_gen_put);
 470
 471 void sock_edemux(struct sk_buff *skb)
 472 {
 473         sock_gen_put(skb->sk);
 474 }
 475 EXPORT_SYMBOL(sock_edemux);
 476
 477 struct sock *__inet_lookup_established(struct net *net,
 478                                   struct inet_hashinfo *hashinfo,
 479                                   const __be32 saddr, const __be16 sport,
 480                                   const __be32 daddr, const u16 hnum,
 481                                   const int dif, const int sdif)
 482 {
 483         INET_ADDR_COOKIE(acookie, saddr, daddr);
 484         const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
 485         struct sock *sk;
 486         const struct hlist_nulls_node *node;
 487         /* Optimize here for direct hit, only listening connections can
 488          * have wildcards anyways.
 489          */
 490         unsigned int hash = inet_ehashfn(net, daddr, hnum, saddr, sport);
 491         unsigned int slot = hash & hashinfo->ehash_mask;
 492         struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
 493
 494 begin:
 495         sk_nulls_for_each_rcu(sk, node, &head->chain) {
 496                 if (sk->sk_hash != hash)
 497                         continue;
 498                 if (likely(inet_match(net, sk, acookie, ports, dif, sdif))) {
 499                         if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
 500                                 goto out;
 501                         if (unlikely(!inet_match(net, sk, acookie,
 502                                                  ports, dif, sdif))) {
 503                                 sock_gen_put(sk);
 504                                 goto begin;
 505                         }
 506                         goto found;
 507                 }
 508         }
 509         /*
 510          * if the nulls value we got at the end of this lookup is
 511          * not the expected one, we must restart lookup.
 512          * We probably met an item that was moved to another chain.
 513          */
 514         if (get_nulls_value(node) != slot)
 515                 goto begin;
 516 out:
 517         sk = NULL;
 518 found:
 519         return sk;
 520 }
 521 EXPORT_SYMBOL_GPL(__inet_lookup_established);
 522
 523 /* called with local bh disabled */
 524 static int __inet_check_established(struct inet_timewait_death_row *death_row,
 525                                     struct sock *sk, __u16 lport,
 526                                     struct inet_timewait_sock **twp)
 527 {
 528         struct inet_hashinfo *hinfo = death_row->hashinfo;
 529         struct inet_sock *inet = inet_sk(sk);
 530         __be32 daddr = inet->inet_rcv_saddr;
 531         __be32 saddr = inet->inet_daddr;
 532         int dif = sk->sk_bound_dev_if;
 533         struct net *net = sock_net(sk);
 534         int sdif = l3mdev_master_ifindex_by_index(net, dif);
 535         INET_ADDR_COOKIE(acookie, saddr, daddr);
 536         const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
 537         unsigned int hash = inet_ehashfn(net, daddr, lport,
 538                                          saddr, inet->inet_dport);
 539         struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
 540         spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
 541         struct sock *sk2;
 542         const struct hlist_nulls_node *node;
 543         struct inet_timewait_sock *tw = NULL;
 544
 545         spin_lock(lock);
 546
 547         sk_nulls_for_each(sk2, node, &head->chain) {
 548                 if (sk2->sk_hash != hash)
 549                         continue;
 550
 551                 if (likely(inet_match(net, sk2, acookie, ports, dif, sdif))) {
 552                         if (sk2->sk_state == TCP_TIME_WAIT) {
 553                                 tw = inet_twsk(sk2);
 554                                 if (twsk_unique(sk, sk2, twp))
 555                                         break;
 556                         }
 557                         goto not_unique;
 558                 }
 559         }
 560
 561         /* Must record num and sport now. Otherwise we will see
 562          * in hash table socket with a funny identity.
 563          */
 564         inet->inet_num = lport;
 565         inet->inet_sport = htons(lport);
 566         sk->sk_hash = hash;
 567         WARN_ON(!sk_unhashed(sk));
 568         __sk_nulls_add_node_rcu(sk, &head->chain);
 569         if (tw) {
 570                 sk_nulls_del_node_init_rcu((struct sock *)tw);
 571                 __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
 572         }
 573         spin_unlock(lock);
 574         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 575
 576         if (twp) {
 577                 *twp = tw;
 578         } else if (tw) {
 579                 /* Silly. Should hash-dance instead... */
 580                 inet_twsk_deschedule_put(tw);
 581         }
 582         return 0;
 583
 584 not_unique:
 585         spin_unlock(lock);
 586         return -EADDRNOTAVAIL;
 587 }
 588
 589 static u64 inet_sk_port_offset(const struct sock *sk)
 590 {
 591         const struct inet_sock *inet = inet_sk(sk);
 592
 593         return secure_ipv4_port_ephemeral(inet->inet_rcv_saddr,
 594                                           inet->inet_daddr,
 595                                           inet->inet_dport);
 596 }
 597
 598 /* Searches for an exsiting socket in the ehash bucket list.
 599  * Returns true if found, false otherwise.
 600  */
 601 static bool inet_ehash_lookup_by_sk(struct sock *sk,
 602                                     struct hlist_nulls_head *list)
 603 {
 604         const __portpair ports = INET_COMBINED_PORTS(sk->sk_dport, sk->sk_num);
 605         const int sdif = sk->sk_bound_dev_if;
 606         const int dif = sk->sk_bound_dev_if;
 607         const struct hlist_nulls_node *node;
 608         struct net *net = sock_net(sk);
 609         struct sock *esk;
 610
 611         INET_ADDR_COOKIE(acookie, sk->sk_daddr, sk->sk_rcv_saddr);
 612
 613         sk_nulls_for_each_rcu(esk, node, list) {
 614                 if (esk->sk_hash != sk->sk_hash)
 615                         continue;
 616                 if (sk->sk_family == AF_INET) {
 617                         if (unlikely(inet_match(net, esk, acookie,
 618                                                 ports, dif, sdif))) {
 619                                 return true;
 620                         }
 621                 }
 622 #if IS_ENABLED(CONFIG_IPV6)
 623                 else if (sk->sk_family == AF_INET6) {
 624                         if (unlikely(inet6_match(net, esk,
 625                                                  &sk->sk_v6_daddr,
 626                                                  &sk->sk_v6_rcv_saddr,
 627                                                  ports, dif, sdif))) {
 628                                 return true;
 629                         }
 630                 }
 631 #endif
 632         }
 633         return false;
 634 }
 635
 636 /* Insert a socket into ehash, and eventually remove another one
 637  * (The another one can be a SYN_RECV or TIMEWAIT)
 638  * If an existing socket already exists, socket sk is not inserted,
 639  * and sets found_dup_sk parameter to true.
 640  */
 641 bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 642 {
 643         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 644         struct inet_ehash_bucket *head;
 645         struct hlist_nulls_head *list;
 646         spinlock_t *lock;
 647         bool ret = true;
 648
 649         WARN_ON_ONCE(!sk_unhashed(sk));
 650
 651         sk->sk_hash = sk_ehashfn(sk);
 652         head = inet_ehash_bucket(hashinfo, sk->sk_hash);
 653         list = &head->chain;
 654         lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 655
 656         spin_lock(lock);
 657         if (osk) {
 658                 WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
 659                 ret = sk_nulls_del_node_init_rcu(osk);
 660         } else if (found_dup_sk) {
 661                 *found_dup_sk = inet_ehash_lookup_by_sk(sk, list);
 662                 if (*found_dup_sk)
 663                         ret = false;
 664         }
 665
 666         if (ret)
 667                 __sk_nulls_add_node_rcu(sk, list);
 668
 669         spin_unlock(lock);
 670
 671         return ret;
 672 }
 673
 674 bool inet_ehash_nolisten(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 675 {
 676         bool ok = inet_ehash_insert(sk, osk, found_dup_sk);
 677
 678         if (ok) {
 679                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 680         } else {
 681                 this_cpu_inc(*sk->sk_prot->orphan_count);
 682                 inet_sk_set_state(sk, TCP_CLOSE);
 683                 sock_set_flag(sk, SOCK_DEAD);
 684                 inet_csk_destroy_sock(sk);
 685         }
 686         return ok;
 687 }
 688 EXPORT_SYMBOL_GPL(inet_ehash_nolisten);
 689
 690 static int inet_reuseport_add_sock(struct sock *sk,
 691                                    struct inet_listen_hashbucket *ilb)
 692 {
 693         struct inet_bind_bucket *tb = inet_csk(sk)->icsk_bind_hash;
 694         const struct hlist_nulls_node *node;
 695         struct sock *sk2;
 696         kuid_t uid = sock_i_uid(sk);
 697
 698         sk_nulls_for_each_rcu(sk2, node, &ilb->nulls_head) {
 699                 if (sk2 != sk &&
 700                     sk2->sk_family == sk->sk_family &&
 701                     ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
 702                     sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
 703                     inet_csk(sk2)->icsk_bind_hash == tb &&
 704                     sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
 705                     inet_rcv_saddr_equal(sk, sk2, false))
 706                         return reuseport_add_sock(sk, sk2,
 707                                                   inet_rcv_saddr_any(sk));
 708         }
 709
 710         return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
 711 }
 712
 713 int __inet_hash(struct sock *sk, struct sock *osk)
 714 {
 715         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 716         struct inet_listen_hashbucket *ilb2;
 717         int err = 0;
 718
 719         if (sk->sk_state != TCP_LISTEN) {
 720                 local_bh_disable();
 721                 inet_ehash_nolisten(sk, osk, NULL);
 722                 local_bh_enable();
 723                 return 0;
 724         }
 725         WARN_ON(!sk_unhashed(sk));
 726         ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 727
 728         spin_lock(&ilb2->lock);
 729         if (sk->sk_reuseport) {
 730                 err = inet_reuseport_add_sock(sk, ilb2);
 731                 if (err)
 732                         goto unlock;
 733         }
 734         sock_set_flag(sk, SOCK_RCU_FREE);
 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_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 741 unlock:
 742         spin_unlock(&ilb2->lock);
 743
 744         return err;
 745 }
 746 EXPORT_SYMBOL(__inet_hash);
 747
 748 int inet_hash(struct sock *sk)
 749 {
 750         int err = 0;
 751
 752         if (sk->sk_state != TCP_CLOSE)
 753                 err = __inet_hash(sk, NULL);
 754
 755         return err;
 756 }
 757 EXPORT_SYMBOL_GPL(inet_hash);
 758
 759 void inet_unhash(struct sock *sk)
 760 {
 761         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 762
 763         if (sk_unhashed(sk))
 764                 return;
 765
 766         if (sk->sk_state == TCP_LISTEN) {
 767                 struct inet_listen_hashbucket *ilb2;
 768
 769                 ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 770                 /* Don't disable bottom halves while acquiring the lock to
 771                  * avoid circular locking dependency on PREEMPT_RT.
 772                  */
 773                 spin_lock(&ilb2->lock);
 774                 if (sk_unhashed(sk)) {
 775                         spin_unlock(&ilb2->lock);
 776                         return;
 777                 }
 778
 779                 if (rcu_access_pointer(sk->sk_reuseport_cb))
 780                         reuseport_stop_listen_sock(sk);
 781
 782                 __sk_nulls_del_node_init_rcu(sk);
 783                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 784                 spin_unlock(&ilb2->lock);
 785         } else {
 786                 spinlock_t *lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 787
 788                 spin_lock_bh(lock);
 789                 if (sk_unhashed(sk)) {
 790                         spin_unlock_bh(lock);
 791                         return;
 792                 }
 793                 __sk_nulls_del_node_init_rcu(sk);
 794                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 795                 spin_unlock_bh(lock);
 796         }
 797 }
 798 EXPORT_SYMBOL_GPL(inet_unhash);
 799
 800 static bool inet_bind2_bucket_match(const struct inet_bind2_bucket *tb,
 801                                     const struct net *net, unsigned short port,
 802                                     int l3mdev, const struct sock *sk)
 803 {
 804         if (!net_eq(ib2_net(tb), net) || tb->port != port ||
 805             tb->l3mdev != l3mdev)
 806                 return false;
 807
 808         return inet_bind2_bucket_addr_match(tb, sk);
 809 }
 810
 811 bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const struct net *net,
 812                                       unsigned short port, int l3mdev, const struct sock *sk)
 813 {
 814         if (!net_eq(ib2_net(tb), net) || tb->port != port ||
 815             tb->l3mdev != l3mdev)
 816                 return false;
 817
 818 #if IS_ENABLED(CONFIG_IPV6)
 819         if (sk->sk_family != tb->family) {
 820                 if (sk->sk_family == AF_INET)
 821                         return ipv6_addr_any(&tb->v6_rcv_saddr) ||
 822                                 ipv6_addr_v4mapped_any(&tb->v6_rcv_saddr);
 823
 824                 return false;
 825         }
 826
 827         if (sk->sk_family == AF_INET6)
 828                 return ipv6_addr_any(&tb->v6_rcv_saddr);
 829 #endif
 830         return tb->rcv_saddr == 0;
 831 }
 832
 833 /* The socket's bhash2 hashbucket spinlock must be held when this is called */
 834 struct inet_bind2_bucket *
 835 inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, const struct net *net,
 836                        unsigned short port, int l3mdev, const struct sock *sk)
 837 {
 838         struct inet_bind2_bucket *bhash2 = NULL;
 839
 840         inet_bind_bucket_for_each(bhash2, &head->chain)
 841                 if (inet_bind2_bucket_match(bhash2, net, port, l3mdev, sk))
 842                         break;
 843
 844         return bhash2;
 845 }
 846
 847 struct inet_bind_hashbucket *
 848 inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port)
 849 {
 850         struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 851         u32 hash;
 852
 853 #if IS_ENABLED(CONFIG_IPV6)
 854         if (sk->sk_family == AF_INET6)
 855                 hash = ipv6_portaddr_hash(net, &in6addr_any, port);
 856         else
 857 #endif
 858                 hash = ipv4_portaddr_hash(net, 0, port);
 859
 860         return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
 861 }
 862
 863 static void inet_update_saddr(struct sock *sk, void *saddr, int family)
 864 {
 865         if (family == AF_INET) {
 866                 inet_sk(sk)->inet_saddr = *(__be32 *)saddr;
 867                 sk_rcv_saddr_set(sk, inet_sk(sk)->inet_saddr);
 868         }
 869 #if IS_ENABLED(CONFIG_IPV6)
 870         else {
 871                 sk->sk_v6_rcv_saddr = *(struct in6_addr *)saddr;
 872         }
 873 #endif
 874 }
 875
 876 static int __inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family, bool reset)
 877 {
 878         struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 879         struct inet_bind_hashbucket *head, *head2;
 880         struct inet_bind2_bucket *tb2, *new_tb2;
 881         int l3mdev = inet_sk_bound_l3mdev(sk);
 882         int port = inet_sk(sk)->inet_num;
 883         struct net *net = sock_net(sk);
 884         int bhash;
 885
 886         if (!inet_csk(sk)->icsk_bind2_hash) {
 887                 /* Not bind()ed before. */
 888                 if (reset)
 889                         inet_reset_saddr(sk);
 890                 else
 891                         inet_update_saddr(sk, saddr, family);
 892
 893                 return 0;
 894         }
 895
 896         /* Allocate a bind2 bucket ahead of time to avoid permanently putting
 897          * the bhash2 table in an inconsistent state if a new tb2 bucket
 898          * allocation fails.
 899          */
 900         new_tb2 = kmem_cache_alloc(hinfo->bind2_bucket_cachep, GFP_ATOMIC);
 901         if (!new_tb2) {
 902                 if (reset) {
 903                         /* The (INADDR_ANY, port) bucket might have already
 904                          * been freed, then we cannot fixup icsk_bind2_hash,
 905                          * so we give up and unlink sk from bhash/bhash2 not
 906                          * to leave inconsistency in bhash2.
 907                          */
 908                         inet_put_port(sk);
 909                         inet_reset_saddr(sk);
 910                 }
 911
 912                 return -ENOMEM;
 913         }
 914
 915         bhash = inet_bhashfn(net, port, hinfo->bhash_size);
 916         head = &hinfo->bhash[bhash];
 917         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 918
 919         /* If we change saddr locklessly, another thread
 920          * iterating over bhash might see corrupted address.
 921          */
 922         spin_lock_bh(&head->lock);
 923
 924         spin_lock(&head2->lock);
 925         __sk_del_bind2_node(sk);
 926         inet_bind2_bucket_destroy(hinfo->bind2_bucket_cachep, inet_csk(sk)->icsk_bind2_hash);
 927         spin_unlock(&head2->lock);
 928
 929         if (reset)
 930                 inet_reset_saddr(sk);
 931         else
 932                 inet_update_saddr(sk, saddr, family);
 933
 934         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 935
 936         spin_lock(&head2->lock);
 937         tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
 938         if (!tb2) {
 939                 tb2 = new_tb2;
 940                 inet_bind2_bucket_init(tb2, net, head2, port, l3mdev, sk);
 941         }
 942         sk_add_bind2_node(sk, &tb2->owners);
 943         inet_csk(sk)->icsk_bind2_hash = tb2;
 944         spin_unlock(&head2->lock);
 945
 946         spin_unlock_bh(&head->lock);
 947
 948         if (tb2 != new_tb2)
 949                 kmem_cache_free(hinfo->bind2_bucket_cachep, new_tb2);
 950
 951         return 0;
 952 }
 953
 954 int inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family)
 955 {
 956         return __inet_bhash2_update_saddr(sk, saddr, family, false);
 957 }
 958 EXPORT_SYMBOL_GPL(inet_bhash2_update_saddr);
 959
 960 void inet_bhash2_reset_saddr(struct sock *sk)
 961 {
 962         if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
 963                 __inet_bhash2_update_saddr(sk, NULL, 0, true);
 964 }
 965 EXPORT_SYMBOL_GPL(inet_bhash2_reset_saddr);
 966
 967 /* RFC 6056 3.3.4.  Algorithm 4: Double-Hash Port Selection Algorithm
 968  * Note that we use 32bit integers (vs RFC 'short integers')
 969  * because 2^16 is not a multiple of num_ephemeral and this
 970  * property might be used by clever attacker.
 971  *
 972  * RFC claims using TABLE_LENGTH=10 buckets gives an improvement, though
 973  * attacks were since demonstrated, thus we use 65536 by default instead
 974  * to really give more isolation and privacy, at the expense of 256kB
 975  * of kernel memory.
 976  */
 977 #define INET_TABLE_PERTURB_SIZE (1 << CONFIG_INET_TABLE_PERTURB_ORDER)
 978 static u32 *table_perturb;
 979
 980 int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 981                 struct sock *sk, u64 port_offset,
 982                 int (*check_established)(struct inet_timewait_death_row *,
 983                         struct sock *, __u16, struct inet_timewait_sock **))
 984 {
 985         struct inet_hashinfo *hinfo = death_row->hashinfo;
 986         struct inet_bind_hashbucket *head, *head2;
 987         struct inet_timewait_sock *tw = NULL;
 988         int port = inet_sk(sk)->inet_num;
 989         struct net *net = sock_net(sk);
 990         struct inet_bind2_bucket *tb2;
 991         struct inet_bind_bucket *tb;
 992         bool tb_created = false;
 993         u32 remaining, offset;
 994         int ret, i, low, high;
 995         int l3mdev;
 996         u32 index;
 997
 998         if (port) {
 999                 local_bh_disable();
1000                 ret = check_established(death_row, sk, port, NULL);
1001                 local_bh_enable();
1002                 return ret;
1003         }
1004
1005         l3mdev = inet_sk_bound_l3mdev(sk);
1006
1007         inet_sk_get_local_port_range(sk, &low, &high);
1008         high++; /* [32768, 60999] -> [32768, 61000[ */
1009         remaining = high - low;
1010         if (likely(remaining > 1))
1011                 remaining &= ~1U;
1012
1013         get_random_sleepable_once(table_perturb,
1014                                   INET_TABLE_PERTURB_SIZE * sizeof(*table_perturb));
1015         index = port_offset & (INET_TABLE_PERTURB_SIZE - 1);
1016
1017         offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32);
1018         offset %= remaining;
1019
1020         /* In first pass we try ports of @low parity.
1021          * inet_csk_get_port() does the opposite choice.
1022          */
1023         offset &= ~1U;
1024 other_parity_scan:
1025         port = low + offset;
1026         for (i = 0; i < remaining; i += 2, port += 2) {
1027                 if (unlikely(port >= high))
1028                         port -= remaining;
1029                 if (inet_is_local_reserved_port(net, port))
1030                         continue;
1031                 head = &hinfo->bhash[inet_bhashfn(net, port,
1032                                                   hinfo->bhash_size)];
1033                 spin_lock_bh(&head->lock);
1034
1035                 /* Does not bother with rcv_saddr checks, because
1036                  * the established check is already unique enough.
1037                  */
1038                 inet_bind_bucket_for_each(tb, &head->chain) {
1039                         if (inet_bind_bucket_match(tb, net, port, l3mdev)) {
1040                                 if (tb->fastreuse >= 0 ||
1041                                     tb->fastreuseport >= 0)
1042                                         goto next_port;
1043                                 WARN_ON(hlist_empty(&tb->owners));
1044                                 if (!check_established(death_row, sk,
1045                                                        port, &tw))
1046                                         goto ok;
1047                                 goto next_port;
1048                         }
1049                 }
1050
1051                 tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
1052                                              net, head, port, l3mdev);
1053                 if (!tb) {
1054                         spin_unlock_bh(&head->lock);
1055                         return -ENOMEM;
1056                 }
1057                 tb_created = true;
1058                 tb->fastreuse = -1;
1059                 tb->fastreuseport = -1;
1060                 goto ok;
1061 next_port:
1062                 spin_unlock_bh(&head->lock);
1063                 cond_resched();
1064         }
1065
1066         offset++;
1067         if ((offset & 1) && remaining > 1)
1068                 goto other_parity_scan;
1069
1070         return -EADDRNOTAVAIL;
1071
1072 ok:
1073         /* Find the corresponding tb2 bucket since we need to
1074          * add the socket to the bhash2 table as well
1075          */
1076         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
1077         spin_lock(&head2->lock);
1078
1079         tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
1080         if (!tb2) {
1081                 tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep, net,
1082                                                head2, port, l3mdev, sk);
1083                 if (!tb2)
1084                         goto error;
1085         }
1086
1087         /* Here we want to add a little bit of randomness to the next source
1088          * port that will be chosen. We use a max() with a random here so that
1089          * on low contention the randomness is maximal and on high contention
1090          * it may be inexistent.
1091          */
1092         i = max_t(int, i, prandom_u32_max(8) * 2);
1093         WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + 2);
1094
1095         /* Head lock still held and bh's disabled */
1096         inet_bind_hash(sk, tb, tb2, port);
1097
1098         if (sk_unhashed(sk)) {
1099                 inet_sk(sk)->inet_sport = htons(port);
1100                 inet_ehash_nolisten(sk, (struct sock *)tw, NULL);
1101         }
1102         if (tw)
1103                 inet_twsk_bind_unhash(tw, hinfo);
1104
1105         spin_unlock(&head2->lock);
1106         spin_unlock(&head->lock);
1107
1108         if (tw)
1109                 inet_twsk_deschedule_put(tw);
1110         local_bh_enable();
1111         return 0;
1112
1113 error:
1114         if (sk_hashed(sk)) {
1115                 spinlock_t *lock = inet_ehash_lockp(hinfo, sk->sk_hash);
1116
1117                 sock_prot_inuse_add(net, sk->sk_prot, -1);
1118
1119                 spin_lock(lock);
1120                 __sk_nulls_del_node_init_rcu(sk);
1121                 spin_unlock(lock);
1122
1123                 sk->sk_hash = 0;
1124                 inet_sk(sk)->inet_sport = 0;
1125                 inet_sk(sk)->inet_num = 0;
1126
1127                 if (tw)
1128                         inet_twsk_bind_unhash(tw, hinfo);
1129         }
1130
1131         spin_unlock(&head2->lock);
1132         if (tb_created)
1133                 inet_bind_bucket_destroy(hinfo->bind_bucket_cachep, tb);
1134         spin_unlock(&head->lock);
1135
1136         if (tw)
1137                 inet_twsk_deschedule_put(tw);
1138
1139         local_bh_enable();
1140
1141         return -ENOMEM;
1142 }
1143
1144 /*
1145  * Bind a port for a connect operation and hash it.
1146  */
1147 int inet_hash_connect(struct inet_timewait_death_row *death_row,
1148                       struct sock *sk)
1149 {
1150         u64 port_offset = 0;
1151
1152         if (!inet_sk(sk)->inet_num)
1153                 port_offset = inet_sk_port_offset(sk);
1154         return __inet_hash_connect(death_row, sk, port_offset,
1155                                    __inet_check_established);
1156 }
1157 EXPORT_SYMBOL_GPL(inet_hash_connect);
1158
1159 static void init_hashinfo_lhash2(struct inet_hashinfo *h)
1160 {
1161         int i;
1162
1163         for (i = 0; i <= h->lhash2_mask; i++) {
1164                 spin_lock_init(&h->lhash2[i].lock);
1165                 INIT_HLIST_NULLS_HEAD(&h->lhash2[i].nulls_head,
1166                                       i + LISTENING_NULLS_BASE);
1167         }
1168 }
1169
1170 void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
1171                                 unsigned long numentries, int scale,
1172                                 unsigned long low_limit,
1173                                 unsigned long high_limit)
1174 {
1175         h->lhash2 = alloc_large_system_hash(name,
1176                                             sizeof(*h->lhash2),
1177                                             numentries,
1178                                             scale,
1179                                             0,
1180                                             NULL,
1181                                             &h->lhash2_mask,
1182                                             low_limit,
1183                                             high_limit);
1184         init_hashinfo_lhash2(h);
1185
1186         /* this one is used for source ports of outgoing connections */
1187         table_perturb = alloc_large_system_hash("Table-perturb",
1188                                                 sizeof(*table_perturb),
1189                                                 INET_TABLE_PERTURB_SIZE,
1190                                                 0, 0, NULL, NULL,
1191                                                 INET_TABLE_PERTURB_SIZE,
1192                                                 INET_TABLE_PERTURB_SIZE);
1193 }
1194
1195 int inet_hashinfo2_init_mod(struct inet_hashinfo *h)
1196 {
1197         h->lhash2 = kmalloc_array(INET_LHTABLE_SIZE, sizeof(*h->lhash2), GFP_KERNEL);
1198         if (!h->lhash2)
1199                 return -ENOMEM;
1200
1201         h->lhash2_mask = INET_LHTABLE_SIZE - 1;
1202         /* INET_LHTABLE_SIZE must be a power of 2 */
1203         BUG_ON(INET_LHTABLE_SIZE & h->lhash2_mask);
1204
1205         init_hashinfo_lhash2(h);
1206         return 0;
1207 }
1208 EXPORT_SYMBOL_GPL(inet_hashinfo2_init_mod);
1209
1210 int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
1211 {
1212         unsigned int locksz = sizeof(spinlock_t);
1213         unsigned int i, nblocks = 1;
1214
1215         if (locksz != 0) {
1216                 /* allocate 2 cache lines or at least one spinlock per cpu */
1217                 nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
1218                 nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
1219
1220                 /* no more locks than number of hash buckets */
1221                 nblocks = min(nblocks, hashinfo->ehash_mask + 1);
1222
1223                 hashinfo->ehash_locks = kvmalloc_array(nblocks, locksz, GFP_KERNEL);
1224                 if (!hashinfo->ehash_locks)
1225                         return -ENOMEM;
1226
1227                 for (i = 0; i < nblocks; i++)
1228                         spin_lock_init(&hashinfo->ehash_locks[i]);
1229         }
1230         hashinfo->ehash_locks_mask = nblocks - 1;
1231         return 0;
1232 }
1233 EXPORT_SYMBOL_GPL(inet_ehash_locks_alloc);
1234
1235 struct inet_hashinfo *inet_pernet_hashinfo_alloc(struct inet_hashinfo *hashinfo,
1236                                                  unsigned int ehash_entries)
1237 {
1238         struct inet_hashinfo *new_hashinfo;
1239         int i;
1240
1241         new_hashinfo = kmemdup(hashinfo, sizeof(*hashinfo), GFP_KERNEL);
1242         if (!new_hashinfo)
1243                 goto err;
1244
1245         new_hashinfo->ehash = vmalloc_huge(ehash_entries * sizeof(struct inet_ehash_bucket),
1246                                            GFP_KERNEL_ACCOUNT);
1247         if (!new_hashinfo->ehash)
1248                 goto free_hashinfo;
1249
1250         new_hashinfo->ehash_mask = ehash_entries - 1;
1251
1252         if (inet_ehash_locks_alloc(new_hashinfo))
1253                 goto free_ehash;
1254
1255         for (i = 0; i < ehash_entries; i++)
1256                 INIT_HLIST_NULLS_HEAD(&new_hashinfo->ehash[i].chain, i);
1257
1258         new_hashinfo->pernet = true;
1259
1260         return new_hashinfo;
1261
1262 free_ehash:
1263         vfree(new_hashinfo->ehash);
1264 free_hashinfo:
1265         kfree(new_hashinfo);
1266 err:
1267         return NULL;
1268 }
1269 EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_alloc);
1270
1271 void inet_pernet_hashinfo_free(struct inet_hashinfo *hashinfo)
1272 {
1273         if (!hashinfo->pernet)
1274                 return;
1275
1276         inet_ehash_locks_free(hashinfo);
1277         vfree(hashinfo->ehash);
1278         kfree(hashinfo);
1279 }
1280 EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_free);