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->bhash2);
  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->bhash2)) {
  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 *tb2,
 104                                    struct net *net,
 105                                    struct inet_bind_hashbucket *head,
 106                                    struct inet_bind_bucket *tb,
 107                                    const struct sock *sk)
 108 {
 109         write_pnet(&tb2->ib_net, net);
 110         tb2->l3mdev = tb->l3mdev;
 111         tb2->port = tb->port;
 112 #if IS_ENABLED(CONFIG_IPV6)
 113         BUILD_BUG_ON(USHRT_MAX < (IPV6_ADDR_ANY | IPV6_ADDR_MAPPED));
 114         if (sk->sk_family == AF_INET6) {
 115                 tb2->addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
 116                 tb2->v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 117         } else {
 118                 tb2->addr_type = IPV6_ADDR_MAPPED;
 119                 ipv6_addr_set_v4mapped(sk->sk_rcv_saddr, &tb2->v6_rcv_saddr);
 120         }
 121 #else
 122         tb2->rcv_saddr = sk->sk_rcv_saddr;
 123 #endif
 124         INIT_HLIST_HEAD(&tb2->owners);
 125         hlist_add_head(&tb2->node, &head->chain);
 126         hlist_add_head(&tb2->bhash_node, &tb->bhash2);
 127 }
 128
 129 struct inet_bind2_bucket *inet_bind2_bucket_create(struct kmem_cache *cachep,
 130                                                    struct net *net,
 131                                                    struct inet_bind_hashbucket *head,
 132                                                    struct inet_bind_bucket *tb,
 133                                                    const struct sock *sk)
 134 {
 135         struct inet_bind2_bucket *tb2 = kmem_cache_alloc(cachep, GFP_ATOMIC);
 136
 137         if (tb2)
 138                 inet_bind2_bucket_init(tb2, net, head, tb, sk);
 139
 140         return tb2;
 141 }
 142
 143 /* Caller must hold hashbucket lock for this tb with local BH disabled */
 144 void inet_bind2_bucket_destroy(struct kmem_cache *cachep, struct inet_bind2_bucket *tb)
 145 {
 146         if (hlist_empty(&tb->owners)) {
 147                 __hlist_del(&tb->node);
 148                 __hlist_del(&tb->bhash_node);
 149                 kmem_cache_free(cachep, tb);
 150         }
 151 }
 152
 153 static bool inet_bind2_bucket_addr_match(const struct inet_bind2_bucket *tb2,
 154                                          const struct sock *sk)
 155 {
 156 #if IS_ENABLED(CONFIG_IPV6)
 157         if (sk->sk_family == AF_INET6)
 158                 return ipv6_addr_equal(&tb2->v6_rcv_saddr, &sk->sk_v6_rcv_saddr);
 159
 160         if (tb2->addr_type != IPV6_ADDR_MAPPED)
 161                 return false;
 162 #endif
 163         return tb2->rcv_saddr == sk->sk_rcv_saddr;
 164 }
 165
 166 void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
 167                     struct inet_bind2_bucket *tb2, unsigned short port)
 168 {
 169         inet_sk(sk)->inet_num = port;
 170         inet_csk(sk)->icsk_bind_hash = tb;
 171         inet_csk(sk)->icsk_bind2_hash = tb2;
 172         sk_add_bind_node(sk, &tb2->owners);
 173 }
 174
 175 /*
 176  * Get rid of any references to a local port held by the given sock.
 177  */
 178 static void __inet_put_port(struct sock *sk)
 179 {
 180         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 181         struct inet_bind_hashbucket *head, *head2;
 182         struct net *net = sock_net(sk);
 183         struct inet_bind_bucket *tb;
 184         int bhash;
 185
 186         bhash = inet_bhashfn(net, inet_sk(sk)->inet_num, hashinfo->bhash_size);
 187         head = &hashinfo->bhash[bhash];
 188         head2 = inet_bhashfn_portaddr(hashinfo, sk, net, inet_sk(sk)->inet_num);
 189
 190         spin_lock(&head->lock);
 191         tb = inet_csk(sk)->icsk_bind_hash;
 192         inet_csk(sk)->icsk_bind_hash = NULL;
 193         inet_sk(sk)->inet_num = 0;
 194
 195         spin_lock(&head2->lock);
 196         if (inet_csk(sk)->icsk_bind2_hash) {
 197                 struct inet_bind2_bucket *tb2 = inet_csk(sk)->icsk_bind2_hash;
 198
 199                 __sk_del_bind_node(sk);
 200                 inet_csk(sk)->icsk_bind2_hash = NULL;
 201                 inet_bind2_bucket_destroy(hashinfo->bind2_bucket_cachep, tb2);
 202         }
 203         spin_unlock(&head2->lock);
 204
 205         inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);
 206         spin_unlock(&head->lock);
 207 }
 208
 209 void inet_put_port(struct sock *sk)
 210 {
 211         local_bh_disable();
 212         __inet_put_port(sk);
 213         local_bh_enable();
 214 }
 215 EXPORT_SYMBOL(inet_put_port);
 216
 217 int __inet_inherit_port(const struct sock *sk, struct sock *child)
 218 {
 219         struct inet_hashinfo *table = tcp_or_dccp_get_hashinfo(sk);
 220         unsigned short port = inet_sk(child)->inet_num;
 221         struct inet_bind_hashbucket *head, *head2;
 222         bool created_inet_bind_bucket = false;
 223         struct net *net = sock_net(sk);
 224         bool update_fastreuse = false;
 225         struct inet_bind2_bucket *tb2;
 226         struct inet_bind_bucket *tb;
 227         int bhash, l3mdev;
 228
 229         bhash = inet_bhashfn(net, port, table->bhash_size);
 230         head = &table->bhash[bhash];
 231         head2 = inet_bhashfn_portaddr(table, child, net, port);
 232
 233         spin_lock(&head->lock);
 234         spin_lock(&head2->lock);
 235         tb = inet_csk(sk)->icsk_bind_hash;
 236         tb2 = inet_csk(sk)->icsk_bind2_hash;
 237         if (unlikely(!tb || !tb2)) {
 238                 spin_unlock(&head2->lock);
 239                 spin_unlock(&head->lock);
 240                 return -ENOENT;
 241         }
 242         if (tb->port != port) {
 243                 l3mdev = inet_sk_bound_l3mdev(sk);
 244
 245                 /* NOTE: using tproxy and redirecting skbs to a proxy
 246                  * on a different listener port breaks the assumption
 247                  * that the listener socket's icsk_bind_hash is the same
 248                  * as that of the child socket. We have to look up or
 249                  * create a new bind bucket for the child here. */
 250                 inet_bind_bucket_for_each(tb, &head->chain) {
 251                         if (inet_bind_bucket_match(tb, net, port, l3mdev))
 252                                 break;
 253                 }
 254                 if (!tb) {
 255                         tb = inet_bind_bucket_create(table->bind_bucket_cachep,
 256                                                      net, head, port, l3mdev);
 257                         if (!tb) {
 258                                 spin_unlock(&head2->lock);
 259                                 spin_unlock(&head->lock);
 260                                 return -ENOMEM;
 261                         }
 262                         created_inet_bind_bucket = true;
 263                 }
 264                 update_fastreuse = true;
 265
 266                 goto bhash2_find;
 267         } else if (!inet_bind2_bucket_addr_match(tb2, child)) {
 268                 l3mdev = inet_sk_bound_l3mdev(sk);
 269
 270 bhash2_find:
 271                 tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, child);
 272                 if (!tb2) {
 273                         tb2 = inet_bind2_bucket_create(table->bind2_bucket_cachep,
 274                                                        net, head2, tb, child);
 275                         if (!tb2)
 276                                 goto error;
 277                 }
 278         }
 279         if (update_fastreuse)
 280                 inet_csk_update_fastreuse(tb, child);
 281         inet_bind_hash(child, tb, tb2, port);
 282         spin_unlock(&head2->lock);
 283         spin_unlock(&head->lock);
 284
 285         return 0;
 286
 287 error:
 288         if (created_inet_bind_bucket)
 289                 inet_bind_bucket_destroy(table->bind_bucket_cachep, tb);
 290         spin_unlock(&head2->lock);
 291         spin_unlock(&head->lock);
 292         return -ENOMEM;
 293 }
 294 EXPORT_SYMBOL_GPL(__inet_inherit_port);
 295
 296 static struct inet_listen_hashbucket *
 297 inet_lhash2_bucket_sk(struct inet_hashinfo *h, struct sock *sk)
 298 {
 299         u32 hash;
 300
 301 #if IS_ENABLED(CONFIG_IPV6)
 302         if (sk->sk_family == AF_INET6)
 303                 hash = ipv6_portaddr_hash(sock_net(sk),
 304                                           &sk->sk_v6_rcv_saddr,
 305                                           inet_sk(sk)->inet_num);
 306         else
 307 #endif
 308                 hash = ipv4_portaddr_hash(sock_net(sk),
 309                                           inet_sk(sk)->inet_rcv_saddr,
 310                                           inet_sk(sk)->inet_num);
 311         return inet_lhash2_bucket(h, hash);
 312 }
 313
 314 static inline int compute_score(struct sock *sk, struct net *net,
 315                                 const unsigned short hnum, const __be32 daddr,
 316                                 const int dif, const int sdif)
 317 {
 318         int score = -1;
 319
 320         if (net_eq(sock_net(sk), net) && sk->sk_num == hnum &&
 321                         !ipv6_only_sock(sk)) {
 322                 if (sk->sk_rcv_saddr != daddr)
 323                         return -1;
 324
 325                 if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
 326                         return -1;
 327                 score =  sk->sk_bound_dev_if ? 2 : 1;
 328
 329                 if (sk->sk_family == PF_INET)
 330                         score++;
 331                 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
 332                         score++;
 333         }
 334         return score;
 335 }
 336
 337 /**
 338  * inet_lookup_reuseport() - execute reuseport logic on AF_INET socket if necessary.
 339  * @net: network namespace.
 340  * @sk: AF_INET socket, must be in TCP_LISTEN state for TCP or TCP_CLOSE for UDP.
 341  * @skb: context for a potential SK_REUSEPORT program.
 342  * @doff: header offset.
 343  * @saddr: source address.
 344  * @sport: source port.
 345  * @daddr: destination address.
 346  * @hnum: destination port in host byte order.
 347  * @ehashfn: hash function used to generate the fallback hash.
 348  *
 349  * Return: NULL if sk doesn't have SO_REUSEPORT set, otherwise a pointer to
 350  *         the selected sock or an error.
 351  */
 352 struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
 353                                    struct sk_buff *skb, int doff,
 354                                    __be32 saddr, __be16 sport,
 355                                    __be32 daddr, unsigned short hnum,
 356                                    inet_ehashfn_t *ehashfn)
 357 {
 358         struct sock *reuse_sk = NULL;
 359         u32 phash;
 360
 361         if (sk->sk_reuseport) {
 362                 phash = INDIRECT_CALL_2(ehashfn, udp_ehashfn, inet_ehashfn,
 363                                         net, daddr, hnum, saddr, sport);
 364                 reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
 365         }
 366         return reuse_sk;
 367 }
 368 EXPORT_SYMBOL_GPL(inet_lookup_reuseport);
 369
 370 /*
 371  * Here are some nice properties to exploit here. The BSD API
 372  * does not allow a listening sock to specify the remote port nor the
 373  * remote address for the connection. So always assume those are both
 374  * wildcarded during the search since they can never be otherwise.
 375  */
 376
 377 /* called with rcu_read_lock() : No refcount taken on the socket */
 378 static struct sock *inet_lhash2_lookup(struct net *net,
 379                                 struct inet_listen_hashbucket *ilb2,
 380                                 struct sk_buff *skb, int doff,
 381                                 const __be32 saddr, __be16 sport,
 382                                 const __be32 daddr, const unsigned short hnum,
 383                                 const int dif, const int sdif)
 384 {
 385         struct sock *sk, *result = NULL;
 386         struct hlist_nulls_node *node;
 387         int score, hiscore = 0;
 388
 389         sk_nulls_for_each_rcu(sk, node, &ilb2->nulls_head) {
 390                 score = compute_score(sk, net, hnum, daddr, dif, sdif);
 391                 if (score > hiscore) {
 392                         result = inet_lookup_reuseport(net, sk, skb, doff,
 393                                                        saddr, sport, daddr, hnum, inet_ehashfn);
 394                         if (result)
 395                                 return result;
 396
 397                         result = sk;
 398                         hiscore = score;
 399                 }
 400         }
 401
 402         return result;
 403 }
 404
 405 struct sock *inet_lookup_run_sk_lookup(struct net *net,
 406                                        int protocol,
 407                                        struct sk_buff *skb, int doff,
 408                                        __be32 saddr, __be16 sport,
 409                                        __be32 daddr, u16 hnum, const int dif,
 410                                        inet_ehashfn_t *ehashfn)
 411 {
 412         struct sock *sk, *reuse_sk;
 413         bool no_reuseport;
 414
 415         no_reuseport = bpf_sk_lookup_run_v4(net, protocol, saddr, sport,
 416                                             daddr, hnum, dif, &sk);
 417         if (no_reuseport || IS_ERR_OR_NULL(sk))
 418                 return sk;
 419
 420         reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum,
 421                                          ehashfn);
 422         if (reuse_sk)
 423                 sk = reuse_sk;
 424         return sk;
 425 }
 426
 427 struct sock *__inet_lookup_listener(struct net *net,
 428                                     struct inet_hashinfo *hashinfo,
 429                                     struct sk_buff *skb, int doff,
 430                                     const __be32 saddr, __be16 sport,
 431                                     const __be32 daddr, const unsigned short hnum,
 432                                     const int dif, const int sdif)
 433 {
 434         struct inet_listen_hashbucket *ilb2;
 435         struct sock *result = NULL;
 436         unsigned int hash2;
 437
 438         /* Lookup redirect from BPF */
 439         if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
 440             hashinfo == net->ipv4.tcp_death_row.hashinfo) {
 441                 result = inet_lookup_run_sk_lookup(net, IPPROTO_TCP, skb, doff,
 442                                                    saddr, sport, daddr, hnum, dif,
 443                                                    inet_ehashfn);
 444                 if (result)
 445                         goto done;
 446         }
 447
 448         hash2 = ipv4_portaddr_hash(net, daddr, hnum);
 449         ilb2 = inet_lhash2_bucket(hashinfo, hash2);
 450
 451         result = inet_lhash2_lookup(net, ilb2, skb, doff,
 452                                     saddr, sport, daddr, hnum,
 453                                     dif, sdif);
 454         if (result)
 455                 goto done;
 456
 457         /* Lookup lhash2 with INADDR_ANY */
 458         hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
 459         ilb2 = inet_lhash2_bucket(hashinfo, hash2);
 460
 461         result = inet_lhash2_lookup(net, ilb2, skb, doff,
 462                                     saddr, sport, htonl(INADDR_ANY), hnum,
 463                                     dif, sdif);
 464 done:
 465         if (IS_ERR(result))
 466                 return NULL;
 467         return result;
 468 }
 469 EXPORT_SYMBOL_GPL(__inet_lookup_listener);
 470
 471 /* All sockets share common refcount, but have different destructors */
 472 void sock_gen_put(struct sock *sk)
 473 {
 474         if (!refcount_dec_and_test(&sk->sk_refcnt))
 475                 return;
 476
 477         if (sk->sk_state == TCP_TIME_WAIT)
 478                 inet_twsk_free(inet_twsk(sk));
 479         else if (sk->sk_state == TCP_NEW_SYN_RECV)
 480                 reqsk_free(inet_reqsk(sk));
 481         else
 482                 sk_free(sk);
 483 }
 484 EXPORT_SYMBOL_GPL(sock_gen_put);
 485
 486 void sock_edemux(struct sk_buff *skb)
 487 {
 488         sock_gen_put(skb->sk);
 489 }
 490 EXPORT_SYMBOL(sock_edemux);
 491
 492 struct sock *__inet_lookup_established(struct net *net,
 493                                   struct inet_hashinfo *hashinfo,
 494                                   const __be32 saddr, const __be16 sport,
 495                                   const __be32 daddr, const u16 hnum,
 496                                   const int dif, const int sdif)
 497 {
 498         INET_ADDR_COOKIE(acookie, saddr, daddr);
 499         const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
 500         struct sock *sk;
 501         const struct hlist_nulls_node *node;
 502         /* Optimize here for direct hit, only listening connections can
 503          * have wildcards anyways.
 504          */
 505         unsigned int hash = inet_ehashfn(net, daddr, hnum, saddr, sport);
 506         unsigned int slot = hash & hashinfo->ehash_mask;
 507         struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
 508
 509 begin:
 510         sk_nulls_for_each_rcu(sk, node, &head->chain) {
 511                 if (sk->sk_hash != hash)
 512                         continue;
 513                 if (likely(inet_match(net, sk, acookie, ports, dif, sdif))) {
 514                         if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
 515                                 goto out;
 516                         if (unlikely(!inet_match(net, sk, acookie,
 517                                                  ports, dif, sdif))) {
 518                                 sock_gen_put(sk);
 519                                 goto begin;
 520                         }
 521                         goto found;
 522                 }
 523         }
 524         /*
 525          * if the nulls value we got at the end of this lookup is
 526          * not the expected one, we must restart lookup.
 527          * We probably met an item that was moved to another chain.
 528          */
 529         if (get_nulls_value(node) != slot)
 530                 goto begin;
 531 out:
 532         sk = NULL;
 533 found:
 534         return sk;
 535 }
 536 EXPORT_SYMBOL_GPL(__inet_lookup_established);
 537
 538 /* called with local bh disabled */
 539 static int __inet_check_established(struct inet_timewait_death_row *death_row,
 540                                     struct sock *sk, __u16 lport,
 541                                     struct inet_timewait_sock **twp)
 542 {
 543         struct inet_hashinfo *hinfo = death_row->hashinfo;
 544         struct inet_sock *inet = inet_sk(sk);
 545         __be32 daddr = inet->inet_rcv_saddr;
 546         __be32 saddr = inet->inet_daddr;
 547         int dif = sk->sk_bound_dev_if;
 548         struct net *net = sock_net(sk);
 549         int sdif = l3mdev_master_ifindex_by_index(net, dif);
 550         INET_ADDR_COOKIE(acookie, saddr, daddr);
 551         const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
 552         unsigned int hash = inet_ehashfn(net, daddr, lport,
 553                                          saddr, inet->inet_dport);
 554         struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
 555         spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
 556         struct sock *sk2;
 557         const struct hlist_nulls_node *node;
 558         struct inet_timewait_sock *tw = NULL;
 559
 560         spin_lock(lock);
 561
 562         sk_nulls_for_each(sk2, node, &head->chain) {
 563                 if (sk2->sk_hash != hash)
 564                         continue;
 565
 566                 if (likely(inet_match(net, sk2, acookie, ports, dif, sdif))) {
 567                         if (sk2->sk_state == TCP_TIME_WAIT) {
 568                                 tw = inet_twsk(sk2);
 569                                 if (twsk_unique(sk, sk2, twp))
 570                                         break;
 571                         }
 572                         goto not_unique;
 573                 }
 574         }
 575
 576         /* Must record num and sport now. Otherwise we will see
 577          * in hash table socket with a funny identity.
 578          */
 579         inet->inet_num = lport;
 580         inet->inet_sport = htons(lport);
 581         sk->sk_hash = hash;
 582         WARN_ON(!sk_unhashed(sk));
 583         __sk_nulls_add_node_rcu(sk, &head->chain);
 584         if (tw) {
 585                 sk_nulls_del_node_init_rcu((struct sock *)tw);
 586                 __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
 587         }
 588         spin_unlock(lock);
 589         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 590
 591         if (twp) {
 592                 *twp = tw;
 593         } else if (tw) {
 594                 /* Silly. Should hash-dance instead... */
 595                 inet_twsk_deschedule_put(tw);
 596         }
 597         return 0;
 598
 599 not_unique:
 600         spin_unlock(lock);
 601         return -EADDRNOTAVAIL;
 602 }
 603
 604 static u64 inet_sk_port_offset(const struct sock *sk)
 605 {
 606         const struct inet_sock *inet = inet_sk(sk);
 607
 608         return secure_ipv4_port_ephemeral(inet->inet_rcv_saddr,
 609                                           inet->inet_daddr,
 610                                           inet->inet_dport);
 611 }
 612
 613 /* Searches for an exsiting socket in the ehash bucket list.
 614  * Returns true if found, false otherwise.
 615  */
 616 static bool inet_ehash_lookup_by_sk(struct sock *sk,
 617                                     struct hlist_nulls_head *list)
 618 {
 619         const __portpair ports = INET_COMBINED_PORTS(sk->sk_dport, sk->sk_num);
 620         const int sdif = sk->sk_bound_dev_if;
 621         const int dif = sk->sk_bound_dev_if;
 622         const struct hlist_nulls_node *node;
 623         struct net *net = sock_net(sk);
 624         struct sock *esk;
 625
 626         INET_ADDR_COOKIE(acookie, sk->sk_daddr, sk->sk_rcv_saddr);
 627
 628         sk_nulls_for_each_rcu(esk, node, list) {
 629                 if (esk->sk_hash != sk->sk_hash)
 630                         continue;
 631                 if (sk->sk_family == AF_INET) {
 632                         if (unlikely(inet_match(net, esk, acookie,
 633                                                 ports, dif, sdif))) {
 634                                 return true;
 635                         }
 636                 }
 637 #if IS_ENABLED(CONFIG_IPV6)
 638                 else if (sk->sk_family == AF_INET6) {
 639                         if (unlikely(inet6_match(net, esk,
 640                                                  &sk->sk_v6_daddr,
 641                                                  &sk->sk_v6_rcv_saddr,
 642                                                  ports, dif, sdif))) {
 643                                 return true;
 644                         }
 645                 }
 646 #endif
 647         }
 648         return false;
 649 }
 650
 651 /* Insert a socket into ehash, and eventually remove another one
 652  * (The another one can be a SYN_RECV or TIMEWAIT)
 653  * If an existing socket already exists, socket sk is not inserted,
 654  * and sets found_dup_sk parameter to true.
 655  */
 656 bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 657 {
 658         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 659         struct inet_ehash_bucket *head;
 660         struct hlist_nulls_head *list;
 661         spinlock_t *lock;
 662         bool ret = true;
 663
 664         WARN_ON_ONCE(!sk_unhashed(sk));
 665
 666         sk->sk_hash = sk_ehashfn(sk);
 667         head = inet_ehash_bucket(hashinfo, sk->sk_hash);
 668         list = &head->chain;
 669         lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 670
 671         spin_lock(lock);
 672         if (osk) {
 673                 WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
 674                 ret = sk_nulls_del_node_init_rcu(osk);
 675         } else if (found_dup_sk) {
 676                 *found_dup_sk = inet_ehash_lookup_by_sk(sk, list);
 677                 if (*found_dup_sk)
 678                         ret = false;
 679         }
 680
 681         if (ret)
 682                 __sk_nulls_add_node_rcu(sk, list);
 683
 684         spin_unlock(lock);
 685
 686         return ret;
 687 }
 688
 689 bool inet_ehash_nolisten(struct sock *sk, struct sock *osk, bool *found_dup_sk)
 690 {
 691         bool ok = inet_ehash_insert(sk, osk, found_dup_sk);
 692
 693         if (ok) {
 694                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 695         } else {
 696                 this_cpu_inc(*sk->sk_prot->orphan_count);
 697                 inet_sk_set_state(sk, TCP_CLOSE);
 698                 sock_set_flag(sk, SOCK_DEAD);
 699                 inet_csk_destroy_sock(sk);
 700         }
 701         return ok;
 702 }
 703 EXPORT_SYMBOL_GPL(inet_ehash_nolisten);
 704
 705 static int inet_reuseport_add_sock(struct sock *sk,
 706                                    struct inet_listen_hashbucket *ilb)
 707 {
 708         struct inet_bind_bucket *tb = inet_csk(sk)->icsk_bind_hash;
 709         const struct hlist_nulls_node *node;
 710         struct sock *sk2;
 711         kuid_t uid = sock_i_uid(sk);
 712
 713         sk_nulls_for_each_rcu(sk2, node, &ilb->nulls_head) {
 714                 if (sk2 != sk &&
 715                     sk2->sk_family == sk->sk_family &&
 716                     ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
 717                     sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
 718                     inet_csk(sk2)->icsk_bind_hash == tb &&
 719                     sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
 720                     inet_rcv_saddr_equal(sk, sk2, false))
 721                         return reuseport_add_sock(sk, sk2,
 722                                                   inet_rcv_saddr_any(sk));
 723         }
 724
 725         return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
 726 }
 727
 728 int __inet_hash(struct sock *sk, struct sock *osk)
 729 {
 730         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 731         struct inet_listen_hashbucket *ilb2;
 732         int err = 0;
 733
 734         if (sk->sk_state != TCP_LISTEN) {
 735                 local_bh_disable();
 736                 inet_ehash_nolisten(sk, osk, NULL);
 737                 local_bh_enable();
 738                 return 0;
 739         }
 740         WARN_ON(!sk_unhashed(sk));
 741         ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 742
 743         spin_lock(&ilb2->lock);
 744         if (sk->sk_reuseport) {
 745                 err = inet_reuseport_add_sock(sk, ilb2);
 746                 if (err)
 747                         goto unlock;
 748         }
 749         sock_set_flag(sk, SOCK_RCU_FREE);
 750         if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 751                 sk->sk_family == AF_INET6)
 752                 __sk_nulls_add_node_tail_rcu(sk, &ilb2->nulls_head);
 753         else
 754                 __sk_nulls_add_node_rcu(sk, &ilb2->nulls_head);
 755         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 756 unlock:
 757         spin_unlock(&ilb2->lock);
 758
 759         return err;
 760 }
 761 EXPORT_SYMBOL(__inet_hash);
 762
 763 int inet_hash(struct sock *sk)
 764 {
 765         int err = 0;
 766
 767         if (sk->sk_state != TCP_CLOSE)
 768                 err = __inet_hash(sk, NULL);
 769
 770         return err;
 771 }
 772 EXPORT_SYMBOL_GPL(inet_hash);
 773
 774 void inet_unhash(struct sock *sk)
 775 {
 776         struct inet_hashinfo *hashinfo = tcp_or_dccp_get_hashinfo(sk);
 777
 778         if (sk_unhashed(sk))
 779                 return;
 780
 781         if (sk->sk_state == TCP_LISTEN) {
 782                 struct inet_listen_hashbucket *ilb2;
 783
 784                 ilb2 = inet_lhash2_bucket_sk(hashinfo, sk);
 785                 /* Don't disable bottom halves while acquiring the lock to
 786                  * avoid circular locking dependency on PREEMPT_RT.
 787                  */
 788                 spin_lock(&ilb2->lock);
 789                 if (sk_unhashed(sk)) {
 790                         spin_unlock(&ilb2->lock);
 791                         return;
 792                 }
 793
 794                 if (rcu_access_pointer(sk->sk_reuseport_cb))
 795                         reuseport_stop_listen_sock(sk);
 796
 797                 __sk_nulls_del_node_init_rcu(sk);
 798                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 799                 spin_unlock(&ilb2->lock);
 800         } else {
 801                 spinlock_t *lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
 802
 803                 spin_lock_bh(lock);
 804                 if (sk_unhashed(sk)) {
 805                         spin_unlock_bh(lock);
 806                         return;
 807                 }
 808                 __sk_nulls_del_node_init_rcu(sk);
 809                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 810                 spin_unlock_bh(lock);
 811         }
 812 }
 813 EXPORT_SYMBOL_GPL(inet_unhash);
 814
 815 static bool inet_bind2_bucket_match(const struct inet_bind2_bucket *tb,
 816                                     const struct net *net, unsigned short port,
 817                                     int l3mdev, const struct sock *sk)
 818 {
 819         if (!net_eq(ib2_net(tb), net) || tb->port != port ||
 820             tb->l3mdev != l3mdev)
 821                 return false;
 822
 823         return inet_bind2_bucket_addr_match(tb, sk);
 824 }
 825
 826 bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const struct net *net,
 827                                       unsigned short port, int l3mdev, const struct sock *sk)
 828 {
 829         if (!net_eq(ib2_net(tb), net) || tb->port != port ||
 830             tb->l3mdev != l3mdev)
 831                 return false;
 832
 833 #if IS_ENABLED(CONFIG_IPV6)
 834         if (tb->addr_type == IPV6_ADDR_ANY)
 835                 return true;
 836
 837         if (tb->addr_type != IPV6_ADDR_MAPPED)
 838                 return false;
 839
 840         if (sk->sk_family == AF_INET6 &&
 841             !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
 842                 return false;
 843 #endif
 844         return tb->rcv_saddr == 0;
 845 }
 846
 847 /* The socket's bhash2 hashbucket spinlock must be held when this is called */
 848 struct inet_bind2_bucket *
 849 inet_bind2_bucket_find(const struct inet_bind_hashbucket *head, const struct net *net,
 850                        unsigned short port, int l3mdev, const struct sock *sk)
 851 {
 852         struct inet_bind2_bucket *bhash2 = NULL;
 853
 854         inet_bind_bucket_for_each(bhash2, &head->chain)
 855                 if (inet_bind2_bucket_match(bhash2, net, port, l3mdev, sk))
 856                         break;
 857
 858         return bhash2;
 859 }
 860
 861 struct inet_bind_hashbucket *
 862 inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port)
 863 {
 864         struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 865         u32 hash;
 866
 867 #if IS_ENABLED(CONFIG_IPV6)
 868         if (sk->sk_family == AF_INET6)
 869                 hash = ipv6_portaddr_hash(net, &in6addr_any, port);
 870         else
 871 #endif
 872                 hash = ipv4_portaddr_hash(net, 0, port);
 873
 874         return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
 875 }
 876
 877 static void inet_update_saddr(struct sock *sk, void *saddr, int family)
 878 {
 879         if (family == AF_INET) {
 880                 inet_sk(sk)->inet_saddr = *(__be32 *)saddr;
 881                 sk_rcv_saddr_set(sk, inet_sk(sk)->inet_saddr);
 882         }
 883 #if IS_ENABLED(CONFIG_IPV6)
 884         else {
 885                 sk->sk_v6_rcv_saddr = *(struct in6_addr *)saddr;
 886         }
 887 #endif
 888 }
 889
 890 static int __inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family, bool reset)
 891 {
 892         struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
 893         struct inet_bind_hashbucket *head, *head2;
 894         struct inet_bind2_bucket *tb2, *new_tb2;
 895         int l3mdev = inet_sk_bound_l3mdev(sk);
 896         int port = inet_sk(sk)->inet_num;
 897         struct net *net = sock_net(sk);
 898         int bhash;
 899
 900         if (!inet_csk(sk)->icsk_bind2_hash) {
 901                 /* Not bind()ed before. */
 902                 if (reset)
 903                         inet_reset_saddr(sk);
 904                 else
 905                         inet_update_saddr(sk, saddr, family);
 906
 907                 return 0;
 908         }
 909
 910         /* Allocate a bind2 bucket ahead of time to avoid permanently putting
 911          * the bhash2 table in an inconsistent state if a new tb2 bucket
 912          * allocation fails.
 913          */
 914         new_tb2 = kmem_cache_alloc(hinfo->bind2_bucket_cachep, GFP_ATOMIC);
 915         if (!new_tb2) {
 916                 if (reset) {
 917                         /* The (INADDR_ANY, port) bucket might have already
 918                          * been freed, then we cannot fixup icsk_bind2_hash,
 919                          * so we give up and unlink sk from bhash/bhash2 not
 920                          * to leave inconsistency in bhash2.
 921                          */
 922                         inet_put_port(sk);
 923                         inet_reset_saddr(sk);
 924                 }
 925
 926                 return -ENOMEM;
 927         }
 928
 929         bhash = inet_bhashfn(net, port, hinfo->bhash_size);
 930         head = &hinfo->bhash[bhash];
 931         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 932
 933         /* If we change saddr locklessly, another thread
 934          * iterating over bhash might see corrupted address.
 935          */
 936         spin_lock_bh(&head->lock);
 937
 938         spin_lock(&head2->lock);
 939         __sk_del_bind_node(sk);
 940         inet_bind2_bucket_destroy(hinfo->bind2_bucket_cachep, inet_csk(sk)->icsk_bind2_hash);
 941         spin_unlock(&head2->lock);
 942
 943         if (reset)
 944                 inet_reset_saddr(sk);
 945         else
 946                 inet_update_saddr(sk, saddr, family);
 947
 948         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
 949
 950         spin_lock(&head2->lock);
 951         tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
 952         if (!tb2) {
 953                 tb2 = new_tb2;
 954                 inet_bind2_bucket_init(tb2, net, head2, inet_csk(sk)->icsk_bind_hash, sk);
 955         }
 956         inet_csk(sk)->icsk_bind2_hash = tb2;
 957         sk_add_bind_node(sk, &tb2->owners);
 958         spin_unlock(&head2->lock);
 959
 960         spin_unlock_bh(&head->lock);
 961
 962         if (tb2 != new_tb2)
 963                 kmem_cache_free(hinfo->bind2_bucket_cachep, new_tb2);
 964
 965         return 0;
 966 }
 967
 968 int inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family)
 969 {
 970         return __inet_bhash2_update_saddr(sk, saddr, family, false);
 971 }
 972 EXPORT_SYMBOL_GPL(inet_bhash2_update_saddr);
 973
 974 void inet_bhash2_reset_saddr(struct sock *sk)
 975 {
 976         if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
 977                 __inet_bhash2_update_saddr(sk, NULL, 0, true);
 978 }
 979 EXPORT_SYMBOL_GPL(inet_bhash2_reset_saddr);
 980
 981 /* RFC 6056 3.3.4.  Algorithm 4: Double-Hash Port Selection Algorithm
 982  * Note that we use 32bit integers (vs RFC 'short integers')
 983  * because 2^16 is not a multiple of num_ephemeral and this
 984  * property might be used by clever attacker.
 985  *
 986  * RFC claims using TABLE_LENGTH=10 buckets gives an improvement, though
 987  * attacks were since demonstrated, thus we use 65536 by default instead
 988  * to really give more isolation and privacy, at the expense of 256kB
 989  * of kernel memory.
 990  */
 991 #define INET_TABLE_PERTURB_SIZE (1 << CONFIG_INET_TABLE_PERTURB_ORDER)
 992 static u32 *table_perturb;
 993
 994 int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 995                 struct sock *sk, u64 port_offset,
 996                 int (*check_established)(struct inet_timewait_death_row *,
 997                         struct sock *, __u16, struct inet_timewait_sock **))
 998 {
 999         struct inet_hashinfo *hinfo = death_row->hashinfo;
1000         struct inet_bind_hashbucket *head, *head2;
1001         struct inet_timewait_sock *tw = NULL;
1002         int port = inet_sk(sk)->inet_num;
1003         struct net *net = sock_net(sk);
1004         struct inet_bind2_bucket *tb2;
1005         struct inet_bind_bucket *tb;
1006         bool tb_created = false;
1007         u32 remaining, offset;
1008         int ret, i, low, high;
1009         bool local_ports;
1010         int step, l3mdev;
1011         u32 index;
1012
1013         if (port) {
1014                 local_bh_disable();
1015                 ret = check_established(death_row, sk, port, NULL);
1016                 local_bh_enable();
1017                 return ret;
1018         }
1019
1020         l3mdev = inet_sk_bound_l3mdev(sk);
1021
1022         local_ports = inet_sk_get_local_port_range(sk, &low, &high);
1023         step = local_ports ? 1 : 2;
1024
1025         high++; /* [32768, 60999] -> [32768, 61000[ */
1026         remaining = high - low;
1027         if (!local_ports && remaining > 1)
1028                 remaining &= ~1U;
1029
1030         get_random_sleepable_once(table_perturb,
1031                                   INET_TABLE_PERTURB_SIZE * sizeof(*table_perturb));
1032         index = port_offset & (INET_TABLE_PERTURB_SIZE - 1);
1033
1034         offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32);
1035         offset %= remaining;
1036
1037         /* In first pass we try ports of @low parity.
1038          * inet_csk_get_port() does the opposite choice.
1039          */
1040         if (!local_ports)
1041                 offset &= ~1U;
1042 other_parity_scan:
1043         port = low + offset;
1044         for (i = 0; i < remaining; i += step, port += step) {
1045                 if (unlikely(port >= high))
1046                         port -= remaining;
1047                 if (inet_is_local_reserved_port(net, port))
1048                         continue;
1049                 head = &hinfo->bhash[inet_bhashfn(net, port,
1050                                                   hinfo->bhash_size)];
1051                 spin_lock_bh(&head->lock);
1052
1053                 /* Does not bother with rcv_saddr checks, because
1054                  * the established check is already unique enough.
1055                  */
1056                 inet_bind_bucket_for_each(tb, &head->chain) {
1057                         if (inet_bind_bucket_match(tb, net, port, l3mdev)) {
1058                                 if (tb->fastreuse >= 0 ||
1059                                     tb->fastreuseport >= 0)
1060                                         goto next_port;
1061                                 WARN_ON(hlist_empty(&tb->bhash2));
1062                                 if (!check_established(death_row, sk,
1063                                                        port, &tw))
1064                                         goto ok;
1065                                 goto next_port;
1066                         }
1067                 }
1068
1069                 tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
1070                                              net, head, port, l3mdev);
1071                 if (!tb) {
1072                         spin_unlock_bh(&head->lock);
1073                         return -ENOMEM;
1074                 }
1075                 tb_created = true;
1076                 tb->fastreuse = -1;
1077                 tb->fastreuseport = -1;
1078                 goto ok;
1079 next_port:
1080                 spin_unlock_bh(&head->lock);
1081                 cond_resched();
1082         }
1083
1084         if (!local_ports) {
1085                 offset++;
1086                 if ((offset & 1) && remaining > 1)
1087                         goto other_parity_scan;
1088         }
1089         return -EADDRNOTAVAIL;
1090
1091 ok:
1092         /* Find the corresponding tb2 bucket since we need to
1093          * add the socket to the bhash2 table as well
1094          */
1095         head2 = inet_bhashfn_portaddr(hinfo, sk, net, port);
1096         spin_lock(&head2->lock);
1097
1098         tb2 = inet_bind2_bucket_find(head2, net, port, l3mdev, sk);
1099         if (!tb2) {
1100                 tb2 = inet_bind2_bucket_create(hinfo->bind2_bucket_cachep, net,
1101                                                head2, tb, sk);
1102                 if (!tb2)
1103                         goto error;
1104         }
1105
1106         /* Here we want to add a little bit of randomness to the next source
1107          * port that will be chosen. We use a max() with a random here so that
1108          * on low contention the randomness is maximal and on high contention
1109          * it may be inexistent.
1110          */
1111         i = max_t(int, i, get_random_u32_below(8) * step);
1112         WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + step);
1113
1114         /* Head lock still held and bh's disabled */
1115         inet_bind_hash(sk, tb, tb2, port);
1116
1117         if (sk_unhashed(sk)) {
1118                 inet_sk(sk)->inet_sport = htons(port);
1119                 inet_ehash_nolisten(sk, (struct sock *)tw, NULL);
1120         }
1121         if (tw)
1122                 inet_twsk_bind_unhash(tw, hinfo);
1123
1124         spin_unlock(&head2->lock);
1125         spin_unlock(&head->lock);
1126
1127         if (tw)
1128                 inet_twsk_deschedule_put(tw);
1129         local_bh_enable();
1130         return 0;
1131
1132 error:
1133         if (sk_hashed(sk)) {
1134                 spinlock_t *lock = inet_ehash_lockp(hinfo, sk->sk_hash);
1135
1136                 sock_prot_inuse_add(net, sk->sk_prot, -1);
1137
1138                 spin_lock(lock);
1139                 __sk_nulls_del_node_init_rcu(sk);
1140                 spin_unlock(lock);
1141
1142                 sk->sk_hash = 0;
1143                 inet_sk(sk)->inet_sport = 0;
1144                 inet_sk(sk)->inet_num = 0;
1145
1146                 if (tw)
1147                         inet_twsk_bind_unhash(tw, hinfo);
1148         }
1149
1150         spin_unlock(&head2->lock);
1151         if (tb_created)
1152                 inet_bind_bucket_destroy(hinfo->bind_bucket_cachep, tb);
1153         spin_unlock(&head->lock);
1154
1155         if (tw)
1156                 inet_twsk_deschedule_put(tw);
1157
1158         local_bh_enable();
1159
1160         return -ENOMEM;
1161 }
1162
1163 /*
1164  * Bind a port for a connect operation and hash it.
1165  */
1166 int inet_hash_connect(struct inet_timewait_death_row *death_row,
1167                       struct sock *sk)
1168 {
1169         u64 port_offset = 0;
1170
1171         if (!inet_sk(sk)->inet_num)
1172                 port_offset = inet_sk_port_offset(sk);
1173         return __inet_hash_connect(death_row, sk, port_offset,
1174                                    __inet_check_established);
1175 }
1176 EXPORT_SYMBOL_GPL(inet_hash_connect);
1177
1178 static void init_hashinfo_lhash2(struct inet_hashinfo *h)
1179 {
1180         int i;
1181
1182         for (i = 0; i <= h->lhash2_mask; i++) {
1183                 spin_lock_init(&h->lhash2[i].lock);
1184                 INIT_HLIST_NULLS_HEAD(&h->lhash2[i].nulls_head,
1185                                       i + LISTENING_NULLS_BASE);
1186         }
1187 }
1188
1189 void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
1190                                 unsigned long numentries, int scale,
1191                                 unsigned long low_limit,
1192                                 unsigned long high_limit)
1193 {
1194         h->lhash2 = alloc_large_system_hash(name,
1195                                             sizeof(*h->lhash2),
1196                                             numentries,
1197                                             scale,
1198                                             0,
1199                                             NULL,
1200                                             &h->lhash2_mask,
1201                                             low_limit,
1202                                             high_limit);
1203         init_hashinfo_lhash2(h);
1204
1205         /* this one is used for source ports of outgoing connections */
1206         table_perturb = alloc_large_system_hash("Table-perturb",
1207                                                 sizeof(*table_perturb),
1208                                                 INET_TABLE_PERTURB_SIZE,
1209                                                 0, 0, NULL, NULL,
1210                                                 INET_TABLE_PERTURB_SIZE,
1211                                                 INET_TABLE_PERTURB_SIZE);
1212 }
1213
1214 int inet_hashinfo2_init_mod(struct inet_hashinfo *h)
1215 {
1216         h->lhash2 = kmalloc_array(INET_LHTABLE_SIZE, sizeof(*h->lhash2), GFP_KERNEL);
1217         if (!h->lhash2)
1218                 return -ENOMEM;
1219
1220         h->lhash2_mask = INET_LHTABLE_SIZE - 1;
1221         /* INET_LHTABLE_SIZE must be a power of 2 */
1222         BUG_ON(INET_LHTABLE_SIZE & h->lhash2_mask);
1223
1224         init_hashinfo_lhash2(h);
1225         return 0;
1226 }
1227 EXPORT_SYMBOL_GPL(inet_hashinfo2_init_mod);
1228
1229 int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
1230 {
1231         unsigned int locksz = sizeof(spinlock_t);
1232         unsigned int i, nblocks = 1;
1233
1234         if (locksz != 0) {
1235                 /* allocate 2 cache lines or at least one spinlock per cpu */
1236                 nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
1237                 nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
1238
1239                 /* no more locks than number of hash buckets */
1240                 nblocks = min(nblocks, hashinfo->ehash_mask + 1);
1241
1242                 hashinfo->ehash_locks = kvmalloc_array(nblocks, locksz, GFP_KERNEL);
1243                 if (!hashinfo->ehash_locks)
1244                         return -ENOMEM;
1245
1246                 for (i = 0; i < nblocks; i++)
1247                         spin_lock_init(&hashinfo->ehash_locks[i]);
1248         }
1249         hashinfo->ehash_locks_mask = nblocks - 1;
1250         return 0;
1251 }
1252 EXPORT_SYMBOL_GPL(inet_ehash_locks_alloc);
1253
1254 struct inet_hashinfo *inet_pernet_hashinfo_alloc(struct inet_hashinfo *hashinfo,
1255                                                  unsigned int ehash_entries)
1256 {
1257         struct inet_hashinfo *new_hashinfo;
1258         int i;
1259
1260         new_hashinfo = kmemdup(hashinfo, sizeof(*hashinfo), GFP_KERNEL);
1261         if (!new_hashinfo)
1262                 goto err;
1263
1264         new_hashinfo->ehash = vmalloc_huge(ehash_entries * sizeof(struct inet_ehash_bucket),
1265                                            GFP_KERNEL_ACCOUNT);
1266         if (!new_hashinfo->ehash)
1267                 goto free_hashinfo;
1268
1269         new_hashinfo->ehash_mask = ehash_entries - 1;
1270
1271         if (inet_ehash_locks_alloc(new_hashinfo))
1272                 goto free_ehash;
1273
1274         for (i = 0; i < ehash_entries; i++)
1275                 INIT_HLIST_NULLS_HEAD(&new_hashinfo->ehash[i].chain, i);
1276
1277         new_hashinfo->pernet = true;
1278
1279         return new_hashinfo;
1280
1281 free_ehash:
1282         vfree(new_hashinfo->ehash);
1283 free_hashinfo:
1284         kfree(new_hashinfo);
1285 err:
1286         return NULL;
1287 }
1288 EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_alloc);
1289
1290 void inet_pernet_hashinfo_free(struct inet_hashinfo *hashinfo)
1291 {
1292         if (!hashinfo->pernet)
1293                 return;
1294
1295         inet_ehash_locks_free(hashinfo);
1296         vfree(hashinfo->ehash);
1297         kfree(hashinfo);
1298 }
1299 EXPORT_SYMBOL_GPL(inet_pernet_hashinfo_free);