net/bridge/br_multicast.c

   1 /*
   2  * Bridge multicast support.
   3  *
   4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  */
  12
  13 #include <linux/err.h>
  14 #include <linux/export.h>
  15 #include <linux/if_ether.h>
  16 #include <linux/igmp.h>
  17 #include <linux/jhash.h>
  18 #include <linux/kernel.h>
  19 #include <linux/log2.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/netfilter_bridge.h>
  22 #include <linux/random.h>
  23 #include <linux/rculist.h>
  24 #include <linux/skbuff.h>
  25 #include <linux/slab.h>
  26 #include <linux/timer.h>
  27 #include <linux/inetdevice.h>
  28 #include <net/ip.h>
  29 #if IS_ENABLED(CONFIG_IPV6)
  30 #include <net/ipv6.h>
  31 #include <net/mld.h>
  32 #include <net/ip6_checksum.h>
  33 #include <net/addrconf.h>
  34 #endif
  35
  36 #include "br_private.h"
  37
  38 static void br_multicast_start_querier(struct net_bridge *br,
  39                                        struct bridge_mcast_own_query *query);
  40 static void br_multicast_add_router(struct net_bridge *br,
  41                                     struct net_bridge_port *port);
  42 static void br_ip4_multicast_leave_group(struct net_bridge *br,
  43                                          struct net_bridge_port *port,
  44                                          __be32 group,
  45                                          __u16 vid);
  46 #if IS_ENABLED(CONFIG_IPV6)
  47 static void br_ip6_multicast_leave_group(struct net_bridge *br,
  48                                          struct net_bridge_port *port,
  49                                          const struct in6_addr *group,
  50                                          __u16 vid);
  51 #endif
  52 unsigned int br_mdb_rehash_seq;
  53
  54 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  55 {
  56         if (a->proto != b->proto)
  57                 return 0;
  58         if (a->vid != b->vid)
  59                 return 0;
  60         switch (a->proto) {
  61         case htons(ETH_P_IP):
  62                 return a->u.ip4 == b->u.ip4;
  63 #if IS_ENABLED(CONFIG_IPV6)
  64         case htons(ETH_P_IPV6):
  65                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  66 #endif
  67         }
  68         return 0;
  69 }
  70
  71 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
  72                                 __u16 vid)
  73 {
  74         return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
  75 }
  76
  77 #if IS_ENABLED(CONFIG_IPV6)
  78 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
  79                                 const struct in6_addr *ip,
  80                                 __u16 vid)
  81 {
  82         return jhash_2words(ipv6_addr_hash(ip), vid,
  83                             mdb->secret) & (mdb->max - 1);
  84 }
  85 #endif
  86
  87 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  88                              struct br_ip *ip)
  89 {
  90         switch (ip->proto) {
  91         case htons(ETH_P_IP):
  92                 return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
  93 #if IS_ENABLED(CONFIG_IPV6)
  94         case htons(ETH_P_IPV6):
  95                 return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
  96 #endif
  97         }
  98         return 0;
  99 }
 100
 101 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
 102         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
 103 {
 104         struct net_bridge_mdb_entry *mp;
 105
 106         hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
 107                 if (br_ip_equal(&mp->addr, dst))
 108                         return mp;
 109         }
 110
 111         return NULL;
 112 }
 113
 114 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
 115                                            struct br_ip *dst)
 116 {
 117         if (!mdb)
 118                 return NULL;
 119
 120         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 121 }
 122
 123 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
 124         struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
 125 {
 126         struct br_ip br_dst;
 127
 128         br_dst.u.ip4 = dst;
 129         br_dst.proto = htons(ETH_P_IP);
 130         br_dst.vid = vid;
 131
 132         return br_mdb_ip_get(mdb, &br_dst);
 133 }
 134
 135 #if IS_ENABLED(CONFIG_IPV6)
 136 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 137         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
 138         __u16 vid)
 139 {
 140         struct br_ip br_dst;
 141
 142         br_dst.u.ip6 = *dst;
 143         br_dst.proto = htons(ETH_P_IPV6);
 144         br_dst.vid = vid;
 145
 146         return br_mdb_ip_get(mdb, &br_dst);
 147 }
 148 #endif
 149
 150 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
 151                                         struct sk_buff *skb, u16 vid)
 152 {
 153         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
 154         struct br_ip ip;
 155
 156         if (br->multicast_disabled)
 157                 return NULL;
 158
 159         if (BR_INPUT_SKB_CB(skb)->igmp)
 160                 return NULL;
 161
 162         ip.proto = skb->protocol;
 163         ip.vid = vid;
 164
 165         switch (skb->protocol) {
 166         case htons(ETH_P_IP):
 167                 ip.u.ip4 = ip_hdr(skb)->daddr;
 168                 break;
 169 #if IS_ENABLED(CONFIG_IPV6)
 170         case htons(ETH_P_IPV6):
 171                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
 172                 break;
 173 #endif
 174         default:
 175                 return NULL;
 176         }
 177
 178         return br_mdb_ip_get(mdb, &ip);
 179 }
 180
 181 static void br_mdb_free(struct rcu_head *head)
 182 {
 183         struct net_bridge_mdb_htable *mdb =
 184                 container_of(head, struct net_bridge_mdb_htable, rcu);
 185         struct net_bridge_mdb_htable *old = mdb->old;
 186
 187         mdb->old = NULL;
 188         kfree(old->mhash);
 189         kfree(old);
 190 }
 191
 192 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
 193                        struct net_bridge_mdb_htable *old,
 194                        int elasticity)
 195 {
 196         struct net_bridge_mdb_entry *mp;
 197         int maxlen;
 198         int len;
 199         int i;
 200
 201         for (i = 0; i < old->max; i++)
 202                 hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
 203                         hlist_add_head(&mp->hlist[new->ver],
 204                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
 205
 206         if (!elasticity)
 207                 return 0;
 208
 209         maxlen = 0;
 210         for (i = 0; i < new->max; i++) {
 211                 len = 0;
 212                 hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
 213                         len++;
 214                 if (len > maxlen)
 215                         maxlen = len;
 216         }
 217
 218         return maxlen > elasticity ? -EINVAL : 0;
 219 }
 220
 221 void br_multicast_free_pg(struct rcu_head *head)
 222 {
 223         struct net_bridge_port_group *p =
 224                 container_of(head, struct net_bridge_port_group, rcu);
 225
 226         kfree(p);
 227 }
 228
 229 static void br_multicast_free_group(struct rcu_head *head)
 230 {
 231         struct net_bridge_mdb_entry *mp =
 232                 container_of(head, struct net_bridge_mdb_entry, rcu);
 233
 234         kfree(mp);
 235 }
 236
 237 static void br_multicast_group_expired(unsigned long data)
 238 {
 239         struct net_bridge_mdb_entry *mp = (void *)data;
 240         struct net_bridge *br = mp->br;
 241         struct net_bridge_mdb_htable *mdb;
 242
 243         spin_lock(&br->multicast_lock);
 244         if (!netif_running(br->dev) || timer_pending(&mp->timer))
 245                 goto out;
 246
 247         mp->mglist = false;
 248
 249         if (mp->ports)
 250                 goto out;
 251
 252         mdb = mlock_dereference(br->mdb, br);
 253
 254         hlist_del_rcu(&mp->hlist[mdb->ver]);
 255         mdb->size--;
 256
 257         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 258
 259 out:
 260         spin_unlock(&br->multicast_lock);
 261 }
 262
 263 static void br_multicast_del_pg(struct net_bridge *br,
 264                                 struct net_bridge_port_group *pg)
 265 {
 266         struct net_bridge_mdb_htable *mdb;
 267         struct net_bridge_mdb_entry *mp;
 268         struct net_bridge_port_group *p;
 269         struct net_bridge_port_group __rcu **pp;
 270
 271         mdb = mlock_dereference(br->mdb, br);
 272
 273         mp = br_mdb_ip_get(mdb, &pg->addr);
 274         if (WARN_ON(!mp))
 275                 return;
 276
 277         for (pp = &mp->ports;
 278              (p = mlock_dereference(*pp, br)) != NULL;
 279              pp = &p->next) {
 280                 if (p != pg)
 281                         continue;
 282
 283                 rcu_assign_pointer(*pp, p->next);
 284                 hlist_del_init(&p->mglist);
 285                 del_timer(&p->timer);
 286                 br_mdb_notify(br->dev, p->port, &pg->addr, RTM_DELMDB,
 287                               p->flags);
 288                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 289
 290                 if (!mp->ports && !mp->mglist &&
 291                     netif_running(br->dev))
 292                         mod_timer(&mp->timer, jiffies);
 293
 294                 return;
 295         }
 296
 297         WARN_ON(1);
 298 }
 299
 300 static void br_multicast_port_group_expired(unsigned long data)
 301 {
 302         struct net_bridge_port_group *pg = (void *)data;
 303         struct net_bridge *br = pg->port->br;
 304
 305         spin_lock(&br->multicast_lock);
 306         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
 307             hlist_unhashed(&pg->mglist) || pg->flags & MDB_PG_FLAGS_PERMANENT)
 308                 goto out;
 309
 310         br_multicast_del_pg(br, pg);
 311
 312 out:
 313         spin_unlock(&br->multicast_lock);
 314 }
 315
 316 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
 317                          int elasticity)
 318 {
 319         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
 320         struct net_bridge_mdb_htable *mdb;
 321         int err;
 322
 323         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
 324         if (!mdb)
 325                 return -ENOMEM;
 326
 327         mdb->max = max;
 328         mdb->old = old;
 329
 330         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
 331         if (!mdb->mhash) {
 332                 kfree(mdb);
 333                 return -ENOMEM;
 334         }
 335
 336         mdb->size = old ? old->size : 0;
 337         mdb->ver = old ? old->ver ^ 1 : 0;
 338
 339         if (!old || elasticity)
 340                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
 341         else
 342                 mdb->secret = old->secret;
 343
 344         if (!old)
 345                 goto out;
 346
 347         err = br_mdb_copy(mdb, old, elasticity);
 348         if (err) {
 349                 kfree(mdb->mhash);
 350                 kfree(mdb);
 351                 return err;
 352         }
 353
 354         br_mdb_rehash_seq++;
 355         call_rcu_bh(&mdb->rcu, br_mdb_free);
 356
 357 out:
 358         rcu_assign_pointer(*mdbp, mdb);
 359
 360         return 0;
 361 }
 362
 363 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
 364                                                     __be32 group)
 365 {
 366         struct sk_buff *skb;
 367         struct igmphdr *ih;
 368         struct ethhdr *eth;
 369         struct iphdr *iph;
 370
 371         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
 372                                                  sizeof(*ih) + 4);
 373         if (!skb)
 374                 goto out;
 375
 376         skb->protocol = htons(ETH_P_IP);
 377
 378         skb_reset_mac_header(skb);
 379         eth = eth_hdr(skb);
 380
 381         ether_addr_copy(eth->h_source, br->dev->dev_addr);
 382         eth->h_dest[0] = 1;
 383         eth->h_dest[1] = 0;
 384         eth->h_dest[2] = 0x5e;
 385         eth->h_dest[3] = 0;
 386         eth->h_dest[4] = 0;
 387         eth->h_dest[5] = 1;
 388         eth->h_proto = htons(ETH_P_IP);
 389         skb_put(skb, sizeof(*eth));
 390
 391         skb_set_network_header(skb, skb->len);
 392         iph = ip_hdr(skb);
 393
 394         iph->version = 4;
 395         iph->ihl = 6;
 396         iph->tos = 0xc0;
 397         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
 398         iph->id = 0;
 399         iph->frag_off = htons(IP_DF);
 400         iph->ttl = 1;
 401         iph->protocol = IPPROTO_IGMP;
 402         iph->saddr = br->multicast_query_use_ifaddr ?
 403                      inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
 404         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
 405         ((u8 *)&iph[1])[0] = IPOPT_RA;
 406         ((u8 *)&iph[1])[1] = 4;
 407         ((u8 *)&iph[1])[2] = 0;
 408         ((u8 *)&iph[1])[3] = 0;
 409         ip_send_check(iph);
 410         skb_put(skb, 24);
 411
 412         skb_set_transport_header(skb, skb->len);
 413         ih = igmp_hdr(skb);
 414         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
 415         ih->code = (group ? br->multicast_last_member_interval :
 416                             br->multicast_query_response_interval) /
 417                    (HZ / IGMP_TIMER_SCALE);
 418         ih->group = group;
 419         ih->csum = 0;
 420         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 421         skb_put(skb, sizeof(*ih));
 422
 423         __skb_pull(skb, sizeof(*eth));
 424
 425 out:
 426         return skb;
 427 }
 428
 429 #if IS_ENABLED(CONFIG_IPV6)
 430 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
 431                                                     const struct in6_addr *group)
 432 {
 433         struct sk_buff *skb;
 434         struct ipv6hdr *ip6h;
 435         struct mld_msg *mldq;
 436         struct ethhdr *eth;
 437         u8 *hopopt;
 438         unsigned long interval;
 439
 440         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
 441                                                  8 + sizeof(*mldq));
 442         if (!skb)
 443                 goto out;
 444
 445         skb->protocol = htons(ETH_P_IPV6);
 446
 447         /* Ethernet header */
 448         skb_reset_mac_header(skb);
 449         eth = eth_hdr(skb);
 450
 451         ether_addr_copy(eth->h_source, br->dev->dev_addr);
 452         eth->h_proto = htons(ETH_P_IPV6);
 453         skb_put(skb, sizeof(*eth));
 454
 455         /* IPv6 header + HbH option */
 456         skb_set_network_header(skb, skb->len);
 457         ip6h = ipv6_hdr(skb);
 458
 459         *(__force __be32 *)ip6h = htonl(0x60000000);
 460         ip6h->payload_len = htons(8 + sizeof(*mldq));
 461         ip6h->nexthdr = IPPROTO_HOPOPTS;
 462         ip6h->hop_limit = 1;
 463         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
 464         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
 465                                &ip6h->saddr)) {
 466                 kfree_skb(skb);
 467                 return NULL;
 468         }
 469         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
 470
 471         hopopt = (u8 *)(ip6h + 1);
 472         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
 473         hopopt[1] = 0;                          /* length of HbH */
 474         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
 475         hopopt[3] = 2;                          /* Length of RA Option */
 476         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
 477         hopopt[5] = 0;
 478         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
 479         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
 480
 481         skb_put(skb, sizeof(*ip6h) + 8);
 482
 483         /* ICMPv6 */
 484         skb_set_transport_header(skb, skb->len);
 485         mldq = (struct mld_msg *) icmp6_hdr(skb);
 486
 487         interval = ipv6_addr_any(group) ?
 488                         br->multicast_query_response_interval :
 489                         br->multicast_last_member_interval;
 490
 491         mldq->mld_type = ICMPV6_MGM_QUERY;
 492         mldq->mld_code = 0;
 493         mldq->mld_cksum = 0;
 494         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
 495         mldq->mld_reserved = 0;
 496         mldq->mld_mca = *group;
 497
 498         /* checksum */
 499         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 500                                           sizeof(*mldq), IPPROTO_ICMPV6,
 501                                           csum_partial(mldq,
 502                                                        sizeof(*mldq), 0));
 503         skb_put(skb, sizeof(*mldq));
 504
 505         __skb_pull(skb, sizeof(*eth));
 506
 507 out:
 508         return skb;
 509 }
 510 #endif
 511
 512 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
 513                                                 struct br_ip *addr)
 514 {
 515         switch (addr->proto) {
 516         case htons(ETH_P_IP):
 517                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
 518 #if IS_ENABLED(CONFIG_IPV6)
 519         case htons(ETH_P_IPV6):
 520                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
 521 #endif
 522         }
 523         return NULL;
 524 }
 525
 526 static struct net_bridge_mdb_entry *br_multicast_get_group(
 527         struct net_bridge *br, struct net_bridge_port *port,
 528         struct br_ip *group, int hash)
 529 {
 530         struct net_bridge_mdb_htable *mdb;
 531         struct net_bridge_mdb_entry *mp;
 532         unsigned int count = 0;
 533         unsigned int max;
 534         int elasticity;
 535         int err;
 536
 537         mdb = rcu_dereference_protected(br->mdb, 1);
 538         hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
 539                 count++;
 540                 if (unlikely(br_ip_equal(group, &mp->addr)))
 541                         return mp;
 542         }
 543
 544         elasticity = 0;
 545         max = mdb->max;
 546
 547         if (unlikely(count > br->hash_elasticity && count)) {
 548                 if (net_ratelimit())
 549                         br_info(br, "Multicast hash table "
 550                                 "chain limit reached: %s\n",
 551                                 port ? port->dev->name : br->dev->name);
 552
 553                 elasticity = br->hash_elasticity;
 554         }
 555
 556         if (mdb->size >= max) {
 557                 max *= 2;
 558                 if (unlikely(max > br->hash_max)) {
 559                         br_warn(br, "Multicast hash table maximum of %d "
 560                                 "reached, disabling snooping: %s\n",
 561                                 br->hash_max,
 562                                 port ? port->dev->name : br->dev->name);
 563                         err = -E2BIG;
 564 disable:
 565                         br->multicast_disabled = 1;
 566                         goto err;
 567                 }
 568         }
 569
 570         if (max > mdb->max || elasticity) {
 571                 if (mdb->old) {
 572                         if (net_ratelimit())
 573                                 br_info(br, "Multicast hash table "
 574                                         "on fire: %s\n",
 575                                         port ? port->dev->name : br->dev->name);
 576                         err = -EEXIST;
 577                         goto err;
 578                 }
 579
 580                 err = br_mdb_rehash(&br->mdb, max, elasticity);
 581                 if (err) {
 582                         br_warn(br, "Cannot rehash multicast "
 583                                 "hash table, disabling snooping: %s, %d, %d\n",
 584                                 port ? port->dev->name : br->dev->name,
 585                                 mdb->size, err);
 586                         goto disable;
 587                 }
 588
 589                 err = -EAGAIN;
 590                 goto err;
 591         }
 592
 593         return NULL;
 594
 595 err:
 596         mp = ERR_PTR(err);
 597         return mp;
 598 }
 599
 600 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
 601         struct net_bridge_port *port, struct br_ip *group)
 602 {
 603         struct net_bridge_mdb_htable *mdb;
 604         struct net_bridge_mdb_entry *mp;
 605         int hash;
 606         int err;
 607
 608         mdb = rcu_dereference_protected(br->mdb, 1);
 609         if (!mdb) {
 610                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
 611                 if (err)
 612                         return ERR_PTR(err);
 613                 goto rehash;
 614         }
 615
 616         hash = br_ip_hash(mdb, group);
 617         mp = br_multicast_get_group(br, port, group, hash);
 618         switch (PTR_ERR(mp)) {
 619         case 0:
 620                 break;
 621
 622         case -EAGAIN:
 623 rehash:
 624                 mdb = rcu_dereference_protected(br->mdb, 1);
 625                 hash = br_ip_hash(mdb, group);
 626                 break;
 627
 628         default:
 629                 goto out;
 630         }
 631
 632         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
 633         if (unlikely(!mp))
 634                 return ERR_PTR(-ENOMEM);
 635
 636         mp->br = br;
 637         mp->addr = *group;
 638         setup_timer(&mp->timer, br_multicast_group_expired,
 639                     (unsigned long)mp);
 640
 641         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
 642         mdb->size++;
 643
 644 out:
 645         return mp;
 646 }
 647
 648 struct net_bridge_port_group *br_multicast_new_port_group(
 649                         struct net_bridge_port *port,
 650                         struct br_ip *group,
 651                         struct net_bridge_port_group __rcu *next,
 652                         unsigned char flags)
 653 {
 654         struct net_bridge_port_group *p;
 655
 656         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 657         if (unlikely(!p))
 658                 return NULL;
 659
 660         p->addr = *group;
 661         p->port = port;
 662         p->flags = flags;
 663         rcu_assign_pointer(p->next, next);
 664         hlist_add_head(&p->mglist, &port->mglist);
 665         setup_timer(&p->timer, br_multicast_port_group_expired,
 666                     (unsigned long)p);
 667         return p;
 668 }
 669
 670 static int br_multicast_add_group(struct net_bridge *br,
 671                                   struct net_bridge_port *port,
 672                                   struct br_ip *group)
 673 {
 674         struct net_bridge_mdb_entry *mp;
 675         struct net_bridge_port_group *p;
 676         struct net_bridge_port_group __rcu **pp;
 677         unsigned long now = jiffies;
 678         int err;
 679
 680         spin_lock(&br->multicast_lock);
 681         if (!netif_running(br->dev) ||
 682             (port && port->state == BR_STATE_DISABLED))
 683                 goto out;
 684
 685         mp = br_multicast_new_group(br, port, group);
 686         err = PTR_ERR(mp);
 687         if (IS_ERR(mp))
 688                 goto err;
 689
 690         if (!port) {
 691                 mp->mglist = true;
 692                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
 693                 goto out;
 694         }
 695
 696         for (pp = &mp->ports;
 697              (p = mlock_dereference(*pp, br)) != NULL;
 698              pp = &p->next) {
 699                 if (p->port == port)
 700                         goto found;
 701                 if ((unsigned long)p->port < (unsigned long)port)
 702                         break;
 703         }
 704
 705         p = br_multicast_new_port_group(port, group, *pp, 0);
 706         if (unlikely(!p))
 707                 goto err;
 708         rcu_assign_pointer(*pp, p);
 709         br_mdb_notify(br->dev, port, group, RTM_NEWMDB, 0);
 710
 711 found:
 712         mod_timer(&p->timer, now + br->multicast_membership_interval);
 713 out:
 714         err = 0;
 715
 716 err:
 717         spin_unlock(&br->multicast_lock);
 718         return err;
 719 }
 720
 721 static int br_ip4_multicast_add_group(struct net_bridge *br,
 722                                       struct net_bridge_port *port,
 723                                       __be32 group,
 724                                       __u16 vid)
 725 {
 726         struct br_ip br_group;
 727
 728         if (ipv4_is_local_multicast(group))
 729                 return 0;
 730
 731         br_group.u.ip4 = group;
 732         br_group.proto = htons(ETH_P_IP);
 733         br_group.vid = vid;
 734
 735         return br_multicast_add_group(br, port, &br_group);
 736 }
 737
 738 #if IS_ENABLED(CONFIG_IPV6)
 739 static int br_ip6_multicast_add_group(struct net_bridge *br,
 740                                       struct net_bridge_port *port,
 741                                       const struct in6_addr *group,
 742                                       __u16 vid)
 743 {
 744         struct br_ip br_group;
 745
 746         if (ipv6_addr_is_ll_all_nodes(group))
 747                 return 0;
 748
 749         br_group.u.ip6 = *group;
 750         br_group.proto = htons(ETH_P_IPV6);
 751         br_group.vid = vid;
 752
 753         return br_multicast_add_group(br, port, &br_group);
 754 }
 755 #endif
 756
 757 static void br_multicast_router_expired(unsigned long data)
 758 {
 759         struct net_bridge_port *port = (void *)data;
 760         struct net_bridge *br = port->br;
 761
 762         spin_lock(&br->multicast_lock);
 763         if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
 764             port->multicast_router == MDB_RTR_TYPE_PERM ||
 765             timer_pending(&port->multicast_router_timer) ||
 766             hlist_unhashed(&port->rlist))
 767                 goto out;
 768
 769         hlist_del_init_rcu(&port->rlist);
 770         br_rtr_notify(br->dev, port, RTM_DELMDB);
 771         /* Don't allow timer refresh if the router expired */
 772         if (port->multicast_router == MDB_RTR_TYPE_TEMP)
 773                 port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
 774
 775 out:
 776         spin_unlock(&br->multicast_lock);
 777 }
 778
 779 static void br_multicast_local_router_expired(unsigned long data)
 780 {
 781 }
 782
 783 static void br_multicast_querier_expired(struct net_bridge *br,
 784                                          struct bridge_mcast_own_query *query)
 785 {
 786         spin_lock(&br->multicast_lock);
 787         if (!netif_running(br->dev) || br->multicast_disabled)
 788                 goto out;
 789
 790         br_multicast_start_querier(br, query);
 791
 792 out:
 793         spin_unlock(&br->multicast_lock);
 794 }
 795
 796 static void br_ip4_multicast_querier_expired(unsigned long data)
 797 {
 798         struct net_bridge *br = (void *)data;
 799
 800         br_multicast_querier_expired(br, &br->ip4_own_query);
 801 }
 802
 803 #if IS_ENABLED(CONFIG_IPV6)
 804 static void br_ip6_multicast_querier_expired(unsigned long data)
 805 {
 806         struct net_bridge *br = (void *)data;
 807
 808         br_multicast_querier_expired(br, &br->ip6_own_query);
 809 }
 810 #endif
 811
 812 static void br_multicast_select_own_querier(struct net_bridge *br,
 813                                             struct br_ip *ip,
 814                                             struct sk_buff *skb)
 815 {
 816         if (ip->proto == htons(ETH_P_IP))
 817                 br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
 818 #if IS_ENABLED(CONFIG_IPV6)
 819         else
 820                 br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
 821 #endif
 822 }
 823
 824 static void __br_multicast_send_query(struct net_bridge *br,
 825                                       struct net_bridge_port *port,
 826                                       struct br_ip *ip)
 827 {
 828         struct sk_buff *skb;
 829
 830         skb = br_multicast_alloc_query(br, ip);
 831         if (!skb)
 832                 return;
 833
 834         if (port) {
 835                 skb->dev = port->dev;
 836                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
 837                         dev_net(port->dev), NULL, skb, NULL, skb->dev,
 838                         br_dev_queue_push_xmit);
 839         } else {
 840                 br_multicast_select_own_querier(br, ip, skb);
 841                 netif_rx(skb);
 842         }
 843 }
 844
 845 static void br_multicast_send_query(struct net_bridge *br,
 846                                     struct net_bridge_port *port,
 847                                     struct bridge_mcast_own_query *own_query)
 848 {
 849         unsigned long time;
 850         struct br_ip br_group;
 851         struct bridge_mcast_other_query *other_query = NULL;
 852
 853         if (!netif_running(br->dev) || br->multicast_disabled ||
 854             !br->multicast_querier)
 855                 return;
 856
 857         memset(&br_group.u, 0, sizeof(br_group.u));
 858
 859         if (port ? (own_query == &port->ip4_own_query) :
 860                    (own_query == &br->ip4_own_query)) {
 861                 other_query = &br->ip4_other_query;
 862                 br_group.proto = htons(ETH_P_IP);
 863 #if IS_ENABLED(CONFIG_IPV6)
 864         } else {
 865                 other_query = &br->ip6_other_query;
 866                 br_group.proto = htons(ETH_P_IPV6);
 867 #endif
 868         }
 869
 870         if (!other_query || timer_pending(&other_query->timer))
 871                 return;
 872
 873         __br_multicast_send_query(br, port, &br_group);
 874
 875         time = jiffies;
 876         time += own_query->startup_sent < br->multicast_startup_query_count ?
 877                 br->multicast_startup_query_interval :
 878                 br->multicast_query_interval;
 879         mod_timer(&own_query->timer, time);
 880 }
 881
 882 static void
 883 br_multicast_port_query_expired(struct net_bridge_port *port,
 884                                 struct bridge_mcast_own_query *query)
 885 {
 886         struct net_bridge *br = port->br;
 887
 888         spin_lock(&br->multicast_lock);
 889         if (port->state == BR_STATE_DISABLED ||
 890             port->state == BR_STATE_BLOCKING)
 891                 goto out;
 892
 893         if (query->startup_sent < br->multicast_startup_query_count)
 894                 query->startup_sent++;
 895
 896         br_multicast_send_query(port->br, port, query);
 897
 898 out:
 899         spin_unlock(&br->multicast_lock);
 900 }
 901
 902 static void br_ip4_multicast_port_query_expired(unsigned long data)
 903 {
 904         struct net_bridge_port *port = (void *)data;
 905
 906         br_multicast_port_query_expired(port, &port->ip4_own_query);
 907 }
 908
 909 #if IS_ENABLED(CONFIG_IPV6)
 910 static void br_ip6_multicast_port_query_expired(unsigned long data)
 911 {
 912         struct net_bridge_port *port = (void *)data;
 913
 914         br_multicast_port_query_expired(port, &port->ip6_own_query);
 915 }
 916 #endif
 917
 918 void br_multicast_add_port(struct net_bridge_port *port)
 919 {
 920         port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
 921
 922         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
 923                     (unsigned long)port);
 924         setup_timer(&port->ip4_own_query.timer,
 925                     br_ip4_multicast_port_query_expired, (unsigned long)port);
 926 #if IS_ENABLED(CONFIG_IPV6)
 927         setup_timer(&port->ip6_own_query.timer,
 928                     br_ip6_multicast_port_query_expired, (unsigned long)port);
 929 #endif
 930 }
 931
 932 void br_multicast_del_port(struct net_bridge_port *port)
 933 {
 934         struct net_bridge *br = port->br;
 935         struct net_bridge_port_group *pg;
 936         struct hlist_node *n;
 937
 938         /* Take care of the remaining groups, only perm ones should be left */
 939         spin_lock_bh(&br->multicast_lock);
 940         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
 941                 br_multicast_del_pg(br, pg);
 942         spin_unlock_bh(&br->multicast_lock);
 943         del_timer_sync(&port->multicast_router_timer);
 944 }
 945
 946 static void br_multicast_enable(struct bridge_mcast_own_query *query)
 947 {
 948         query->startup_sent = 0;
 949
 950         if (try_to_del_timer_sync(&query->timer) >= 0 ||
 951             del_timer(&query->timer))
 952                 mod_timer(&query->timer, jiffies);
 953 }
 954
 955 void br_multicast_enable_port(struct net_bridge_port *port)
 956 {
 957         struct net_bridge *br = port->br;
 958
 959         spin_lock(&br->multicast_lock);
 960         if (br->multicast_disabled || !netif_running(br->dev))
 961                 goto out;
 962
 963         br_multicast_enable(&port->ip4_own_query);
 964 #if IS_ENABLED(CONFIG_IPV6)
 965         br_multicast_enable(&port->ip6_own_query);
 966 #endif
 967         if (port->multicast_router == MDB_RTR_TYPE_PERM &&
 968             hlist_unhashed(&port->rlist))
 969                 br_multicast_add_router(br, port);
 970
 971 out:
 972         spin_unlock(&br->multicast_lock);
 973 }
 974
 975 void br_multicast_disable_port(struct net_bridge_port *port)
 976 {
 977         struct net_bridge *br = port->br;
 978         struct net_bridge_port_group *pg;
 979         struct hlist_node *n;
 980
 981         spin_lock(&br->multicast_lock);
 982         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
 983                 if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
 984                         br_multicast_del_pg(br, pg);
 985
 986         if (!hlist_unhashed(&port->rlist)) {
 987                 hlist_del_init_rcu(&port->rlist);
 988                 br_rtr_notify(br->dev, port, RTM_DELMDB);
 989                 /* Don't allow timer refresh if disabling */
 990                 if (port->multicast_router == MDB_RTR_TYPE_TEMP)
 991                         port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
 992         }
 993         del_timer(&port->multicast_router_timer);
 994         del_timer(&port->ip4_own_query.timer);
 995 #if IS_ENABLED(CONFIG_IPV6)
 996         del_timer(&port->ip6_own_query.timer);
 997 #endif
 998         spin_unlock(&br->multicast_lock);
 999 }
1000
1001 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
1002                                          struct net_bridge_port *port,
1003                                          struct sk_buff *skb,
1004                                          u16 vid)
1005 {
1006         struct igmpv3_report *ih;
1007         struct igmpv3_grec *grec;
1008         int i;
1009         int len;
1010         int num;
1011         int type;
1012         int err = 0;
1013         __be32 group;
1014
1015         ih = igmpv3_report_hdr(skb);
1016         num = ntohs(ih->ngrec);
1017         len = skb_transport_offset(skb) + sizeof(*ih);
1018
1019         for (i = 0; i < num; i++) {
1020                 len += sizeof(*grec);
1021                 if (!pskb_may_pull(skb, len))
1022                         return -EINVAL;
1023
1024                 grec = (void *)(skb->data + len - sizeof(*grec));
1025                 group = grec->grec_mca;
1026                 type = grec->grec_type;
1027
1028                 len += ntohs(grec->grec_nsrcs) * 4;
1029                 if (!pskb_may_pull(skb, len))
1030                         return -EINVAL;
1031
1032                 /* We treat this as an IGMPv2 report for now. */
1033                 switch (type) {
1034                 case IGMPV3_MODE_IS_INCLUDE:
1035                 case IGMPV3_MODE_IS_EXCLUDE:
1036                 case IGMPV3_CHANGE_TO_INCLUDE:
1037                 case IGMPV3_CHANGE_TO_EXCLUDE:
1038                 case IGMPV3_ALLOW_NEW_SOURCES:
1039                 case IGMPV3_BLOCK_OLD_SOURCES:
1040                         break;
1041
1042                 default:
1043                         continue;
1044                 }
1045
1046                 if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
1047                      type == IGMPV3_MODE_IS_INCLUDE) &&
1048                     ntohs(grec->grec_nsrcs) == 0) {
1049                         br_ip4_multicast_leave_group(br, port, group, vid);
1050                 } else {
1051                         err = br_ip4_multicast_add_group(br, port, group, vid);
1052                         if (err)
1053                                 break;
1054                 }
1055         }
1056
1057         return err;
1058 }
1059
1060 #if IS_ENABLED(CONFIG_IPV6)
1061 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1062                                         struct net_bridge_port *port,
1063                                         struct sk_buff *skb,
1064                                         u16 vid)
1065 {
1066         struct icmp6hdr *icmp6h;
1067         struct mld2_grec *grec;
1068         int i;
1069         int len;
1070         int num;
1071         int err = 0;
1072
1073         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1074                 return -EINVAL;
1075
1076         icmp6h = icmp6_hdr(skb);
1077         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1078         len = skb_transport_offset(skb) + sizeof(*icmp6h);
1079
1080         for (i = 0; i < num; i++) {
1081                 __be16 *nsrcs, _nsrcs;
1082
1083                 nsrcs = skb_header_pointer(skb,
1084                                            len + offsetof(struct mld2_grec,
1085                                                           grec_nsrcs),
1086                                            sizeof(_nsrcs), &_nsrcs);
1087                 if (!nsrcs)
1088                         return -EINVAL;
1089
1090                 if (!pskb_may_pull(skb,
1091                                    len + sizeof(*grec) +
1092                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1093                         return -EINVAL;
1094
1095                 grec = (struct mld2_grec *)(skb->data + len);
1096                 len += sizeof(*grec) +
1097                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1098
1099                 /* We treat these as MLDv1 reports for now. */
1100                 switch (grec->grec_type) {
1101                 case MLD2_MODE_IS_INCLUDE:
1102                 case MLD2_MODE_IS_EXCLUDE:
1103                 case MLD2_CHANGE_TO_INCLUDE:
1104                 case MLD2_CHANGE_TO_EXCLUDE:
1105                 case MLD2_ALLOW_NEW_SOURCES:
1106                 case MLD2_BLOCK_OLD_SOURCES:
1107                         break;
1108
1109                 default:
1110                         continue;
1111                 }
1112
1113                 if ((grec->grec_type == MLD2_CHANGE_TO_INCLUDE ||
1114                      grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
1115                     ntohs(*nsrcs) == 0) {
1116                         br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
1117                                                      vid);
1118                 } else {
1119                         err = br_ip6_multicast_add_group(br, port,
1120                                                          &grec->grec_mca, vid);
1121                         if (!err)
1122                                 break;
1123                 }
1124         }
1125
1126         return err;
1127 }
1128 #endif
1129
1130 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1131                                             struct net_bridge_port *port,
1132                                             __be32 saddr)
1133 {
1134         if (!timer_pending(&br->ip4_own_query.timer) &&
1135             !timer_pending(&br->ip4_other_query.timer))
1136                 goto update;
1137
1138         if (!br->ip4_querier.addr.u.ip4)
1139                 goto update;
1140
1141         if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1142                 goto update;
1143
1144         return false;
1145
1146 update:
1147         br->ip4_querier.addr.u.ip4 = saddr;
1148
1149         /* update protected by general multicast_lock by caller */
1150         rcu_assign_pointer(br->ip4_querier.port, port);
1151
1152         return true;
1153 }
1154
1155 #if IS_ENABLED(CONFIG_IPV6)
1156 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1157                                             struct net_bridge_port *port,
1158                                             struct in6_addr *saddr)
1159 {
1160         if (!timer_pending(&br->ip6_own_query.timer) &&
1161             !timer_pending(&br->ip6_other_query.timer))
1162                 goto update;
1163
1164         if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1165                 goto update;
1166
1167         return false;
1168
1169 update:
1170         br->ip6_querier.addr.u.ip6 = *saddr;
1171
1172         /* update protected by general multicast_lock by caller */
1173         rcu_assign_pointer(br->ip6_querier.port, port);
1174
1175         return true;
1176 }
1177 #endif
1178
1179 static bool br_multicast_select_querier(struct net_bridge *br,
1180                                         struct net_bridge_port *port,
1181                                         struct br_ip *saddr)
1182 {
1183         switch (saddr->proto) {
1184         case htons(ETH_P_IP):
1185                 return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1186 #if IS_ENABLED(CONFIG_IPV6)
1187         case htons(ETH_P_IPV6):
1188                 return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1189 #endif
1190         }
1191
1192         return false;
1193 }
1194
1195 static void
1196 br_multicast_update_query_timer(struct net_bridge *br,
1197                                 struct bridge_mcast_other_query *query,
1198                                 unsigned long max_delay)
1199 {
1200         if (!timer_pending(&query->timer))
1201                 query->delay_time = jiffies + max_delay;
1202
1203         mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1204 }
1205
1206 /*
1207  * Add port to router_list
1208  *  list is maintained ordered by pointer value
1209  *  and locked by br->multicast_lock and RCU
1210  */
1211 static void br_multicast_add_router(struct net_bridge *br,
1212                                     struct net_bridge_port *port)
1213 {
1214         struct net_bridge_port *p;
1215         struct hlist_node *slot = NULL;
1216
1217         if (!hlist_unhashed(&port->rlist))
1218                 return;
1219
1220         hlist_for_each_entry(p, &br->router_list, rlist) {
1221                 if ((unsigned long) port >= (unsigned long) p)
1222                         break;
1223                 slot = &p->rlist;
1224         }
1225
1226         if (slot)
1227                 hlist_add_behind_rcu(&port->rlist, slot);
1228         else
1229                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1230         br_rtr_notify(br->dev, port, RTM_NEWMDB);
1231 }
1232
1233 static void br_multicast_mark_router(struct net_bridge *br,
1234                                      struct net_bridge_port *port)
1235 {
1236         unsigned long now = jiffies;
1237
1238         if (!port) {
1239                 if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY)
1240                         mod_timer(&br->multicast_router_timer,
1241                                   now + br->multicast_querier_interval);
1242                 return;
1243         }
1244
1245         if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
1246             port->multicast_router == MDB_RTR_TYPE_PERM)
1247                 return;
1248
1249         br_multicast_add_router(br, port);
1250
1251         mod_timer(&port->multicast_router_timer,
1252                   now + br->multicast_querier_interval);
1253 }
1254
1255 static void br_multicast_query_received(struct net_bridge *br,
1256                                         struct net_bridge_port *port,
1257                                         struct bridge_mcast_other_query *query,
1258                                         struct br_ip *saddr,
1259                                         unsigned long max_delay)
1260 {
1261         if (!br_multicast_select_querier(br, port, saddr))
1262                 return;
1263
1264         br_multicast_update_query_timer(br, query, max_delay);
1265         br_multicast_mark_router(br, port);
1266 }
1267
1268 static int br_ip4_multicast_query(struct net_bridge *br,
1269                                   struct net_bridge_port *port,
1270                                   struct sk_buff *skb,
1271                                   u16 vid)
1272 {
1273         const struct iphdr *iph = ip_hdr(skb);
1274         struct igmphdr *ih = igmp_hdr(skb);
1275         struct net_bridge_mdb_entry *mp;
1276         struct igmpv3_query *ih3;
1277         struct net_bridge_port_group *p;
1278         struct net_bridge_port_group __rcu **pp;
1279         struct br_ip saddr;
1280         unsigned long max_delay;
1281         unsigned long now = jiffies;
1282         __be32 group;
1283         int err = 0;
1284
1285         spin_lock(&br->multicast_lock);
1286         if (!netif_running(br->dev) ||
1287             (port && port->state == BR_STATE_DISABLED))
1288                 goto out;
1289
1290         group = ih->group;
1291
1292         if (skb->len == sizeof(*ih)) {
1293                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1294
1295                 if (!max_delay) {
1296                         max_delay = 10 * HZ;
1297                         group = 0;
1298                 }
1299         } else if (skb->len >= sizeof(*ih3)) {
1300                 ih3 = igmpv3_query_hdr(skb);
1301                 if (ih3->nsrcs)
1302                         goto out;
1303
1304                 max_delay = ih3->code ?
1305                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1306         } else {
1307                 goto out;
1308         }
1309
1310         if (!group) {
1311                 saddr.proto = htons(ETH_P_IP);
1312                 saddr.u.ip4 = iph->saddr;
1313
1314                 br_multicast_query_received(br, port, &br->ip4_other_query,
1315                                             &saddr, max_delay);
1316                 goto out;
1317         }
1318
1319         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1320         if (!mp)
1321                 goto out;
1322
1323         max_delay *= br->multicast_last_member_count;
1324
1325         if (mp->mglist &&
1326             (timer_pending(&mp->timer) ?
1327              time_after(mp->timer.expires, now + max_delay) :
1328              try_to_del_timer_sync(&mp->timer) >= 0))
1329                 mod_timer(&mp->timer, now + max_delay);
1330
1331         for (pp = &mp->ports;
1332              (p = mlock_dereference(*pp, br)) != NULL;
1333              pp = &p->next) {
1334                 if (timer_pending(&p->timer) ?
1335                     time_after(p->timer.expires, now + max_delay) :
1336                     try_to_del_timer_sync(&p->timer) >= 0)
1337                         mod_timer(&p->timer, now + max_delay);
1338         }
1339
1340 out:
1341         spin_unlock(&br->multicast_lock);
1342         return err;
1343 }
1344
1345 #if IS_ENABLED(CONFIG_IPV6)
1346 static int br_ip6_multicast_query(struct net_bridge *br,
1347                                   struct net_bridge_port *port,
1348                                   struct sk_buff *skb,
1349                                   u16 vid)
1350 {
1351         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1352         struct mld_msg *mld;
1353         struct net_bridge_mdb_entry *mp;
1354         struct mld2_query *mld2q;
1355         struct net_bridge_port_group *p;
1356         struct net_bridge_port_group __rcu **pp;
1357         struct br_ip saddr;
1358         unsigned long max_delay;
1359         unsigned long now = jiffies;
1360         const struct in6_addr *group = NULL;
1361         bool is_general_query;
1362         int err = 0;
1363
1364         spin_lock(&br->multicast_lock);
1365         if (!netif_running(br->dev) ||
1366             (port && port->state == BR_STATE_DISABLED))
1367                 goto out;
1368
1369         if (skb->len == sizeof(*mld)) {
1370                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1371                         err = -EINVAL;
1372                         goto out;
1373                 }
1374                 mld = (struct mld_msg *) icmp6_hdr(skb);
1375                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1376                 if (max_delay)
1377                         group = &mld->mld_mca;
1378         } else {
1379                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1380                         err = -EINVAL;
1381                         goto out;
1382                 }
1383                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1384                 if (!mld2q->mld2q_nsrcs)
1385                         group = &mld2q->mld2q_mca;
1386
1387                 max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1388         }
1389
1390         is_general_query = group && ipv6_addr_any(group);
1391
1392         if (is_general_query) {
1393                 saddr.proto = htons(ETH_P_IPV6);
1394                 saddr.u.ip6 = ip6h->saddr;
1395
1396                 br_multicast_query_received(br, port, &br->ip6_other_query,
1397                                             &saddr, max_delay);
1398                 goto out;
1399         } else if (!group) {
1400                 goto out;
1401         }
1402
1403         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1404         if (!mp)
1405                 goto out;
1406
1407         max_delay *= br->multicast_last_member_count;
1408         if (mp->mglist &&
1409             (timer_pending(&mp->timer) ?
1410              time_after(mp->timer.expires, now + max_delay) :
1411              try_to_del_timer_sync(&mp->timer) >= 0))
1412                 mod_timer(&mp->timer, now + max_delay);
1413
1414         for (pp = &mp->ports;
1415              (p = mlock_dereference(*pp, br)) != NULL;
1416              pp = &p->next) {
1417                 if (timer_pending(&p->timer) ?
1418                     time_after(p->timer.expires, now + max_delay) :
1419                     try_to_del_timer_sync(&p->timer) >= 0)
1420                         mod_timer(&p->timer, now + max_delay);
1421         }
1422
1423 out:
1424         spin_unlock(&br->multicast_lock);
1425         return err;
1426 }
1427 #endif
1428
1429 static void
1430 br_multicast_leave_group(struct net_bridge *br,
1431                          struct net_bridge_port *port,
1432                          struct br_ip *group,
1433                          struct bridge_mcast_other_query *other_query,
1434                          struct bridge_mcast_own_query *own_query)
1435 {
1436         struct net_bridge_mdb_htable *mdb;
1437         struct net_bridge_mdb_entry *mp;
1438         struct net_bridge_port_group *p;
1439         unsigned long now;
1440         unsigned long time;
1441
1442         spin_lock(&br->multicast_lock);
1443         if (!netif_running(br->dev) ||
1444             (port && port->state == BR_STATE_DISABLED))
1445                 goto out;
1446
1447         mdb = mlock_dereference(br->mdb, br);
1448         mp = br_mdb_ip_get(mdb, group);
1449         if (!mp)
1450                 goto out;
1451
1452         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1453                 struct net_bridge_port_group __rcu **pp;
1454
1455                 for (pp = &mp->ports;
1456                      (p = mlock_dereference(*pp, br)) != NULL;
1457                      pp = &p->next) {
1458                         if (p->port != port)
1459                                 continue;
1460
1461                         rcu_assign_pointer(*pp, p->next);
1462                         hlist_del_init(&p->mglist);
1463                         del_timer(&p->timer);
1464                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1465                         br_mdb_notify(br->dev, port, group, RTM_DELMDB,
1466                                       p->flags);
1467
1468                         if (!mp->ports && !mp->mglist &&
1469                             netif_running(br->dev))
1470                                 mod_timer(&mp->timer, jiffies);
1471                 }
1472                 goto out;
1473         }
1474
1475         if (timer_pending(&other_query->timer))
1476                 goto out;
1477
1478         if (br->multicast_querier) {
1479                 __br_multicast_send_query(br, port, &mp->addr);
1480
1481                 time = jiffies + br->multicast_last_member_count *
1482                                  br->multicast_last_member_interval;
1483
1484                 mod_timer(&own_query->timer, time);
1485
1486                 for (p = mlock_dereference(mp->ports, br);
1487                      p != NULL;
1488                      p = mlock_dereference(p->next, br)) {
1489                         if (p->port != port)
1490                                 continue;
1491
1492                         if (!hlist_unhashed(&p->mglist) &&
1493                             (timer_pending(&p->timer) ?
1494                              time_after(p->timer.expires, time) :
1495                              try_to_del_timer_sync(&p->timer) >= 0)) {
1496                                 mod_timer(&p->timer, time);
1497                         }
1498
1499                         break;
1500                 }
1501         }
1502
1503         now = jiffies;
1504         time = now + br->multicast_last_member_count *
1505                      br->multicast_last_member_interval;
1506
1507         if (!port) {
1508                 if (mp->mglist &&
1509                     (timer_pending(&mp->timer) ?
1510                      time_after(mp->timer.expires, time) :
1511                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1512                         mod_timer(&mp->timer, time);
1513                 }
1514
1515                 goto out;
1516         }
1517
1518         for (p = mlock_dereference(mp->ports, br);
1519              p != NULL;
1520              p = mlock_dereference(p->next, br)) {
1521                 if (p->port != port)
1522                         continue;
1523
1524                 if (!hlist_unhashed(&p->mglist) &&
1525                     (timer_pending(&p->timer) ?
1526                      time_after(p->timer.expires, time) :
1527                      try_to_del_timer_sync(&p->timer) >= 0)) {
1528                         mod_timer(&p->timer, time);
1529                 }
1530
1531                 break;
1532         }
1533 out:
1534         spin_unlock(&br->multicast_lock);
1535 }
1536
1537 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1538                                          struct net_bridge_port *port,
1539                                          __be32 group,
1540                                          __u16 vid)
1541 {
1542         struct br_ip br_group;
1543         struct bridge_mcast_own_query *own_query;
1544
1545         if (ipv4_is_local_multicast(group))
1546                 return;
1547
1548         own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1549
1550         br_group.u.ip4 = group;
1551         br_group.proto = htons(ETH_P_IP);
1552         br_group.vid = vid;
1553
1554         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1555                                  own_query);
1556 }
1557
1558 #if IS_ENABLED(CONFIG_IPV6)
1559 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1560                                          struct net_bridge_port *port,
1561                                          const struct in6_addr *group,
1562                                          __u16 vid)
1563 {
1564         struct br_ip br_group;
1565         struct bridge_mcast_own_query *own_query;
1566
1567         if (ipv6_addr_is_ll_all_nodes(group))
1568                 return;
1569
1570         own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1571
1572         br_group.u.ip6 = *group;
1573         br_group.proto = htons(ETH_P_IPV6);
1574         br_group.vid = vid;
1575
1576         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1577                                  own_query);
1578 }
1579 #endif
1580
1581 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1582                                  struct net_bridge_port *port,
1583                                  struct sk_buff *skb,
1584                                  u16 vid)
1585 {
1586         struct sk_buff *skb_trimmed = NULL;
1587         struct igmphdr *ih;
1588         int err;
1589
1590         err = ip_mc_check_igmp(skb, &skb_trimmed);
1591
1592         if (err == -ENOMSG) {
1593                 if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr))
1594                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1595                 return 0;
1596         } else if (err < 0) {
1597                 return err;
1598         }
1599
1600         BR_INPUT_SKB_CB(skb)->igmp = 1;
1601         ih = igmp_hdr(skb);
1602
1603         switch (ih->type) {
1604         case IGMP_HOST_MEMBERSHIP_REPORT:
1605         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1606                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1607                 err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1608                 break;
1609         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1610                 err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
1611                 break;
1612         case IGMP_HOST_MEMBERSHIP_QUERY:
1613                 err = br_ip4_multicast_query(br, port, skb_trimmed, vid);
1614                 break;
1615         case IGMP_HOST_LEAVE_MESSAGE:
1616                 br_ip4_multicast_leave_group(br, port, ih->group, vid);
1617                 break;
1618         }
1619
1620         if (skb_trimmed && skb_trimmed != skb)
1621                 kfree_skb(skb_trimmed);
1622
1623         return err;
1624 }
1625
1626 #if IS_ENABLED(CONFIG_IPV6)
1627 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1628                                  struct net_bridge_port *port,
1629                                  struct sk_buff *skb,
1630                                  u16 vid)
1631 {
1632         struct sk_buff *skb_trimmed = NULL;
1633         struct mld_msg *mld;
1634         int err;
1635
1636         err = ipv6_mc_check_mld(skb, &skb_trimmed);
1637
1638         if (err == -ENOMSG) {
1639                 if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
1640                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1641                 return 0;
1642         } else if (err < 0) {
1643                 return err;
1644         }
1645
1646         BR_INPUT_SKB_CB(skb)->igmp = 1;
1647         mld = (struct mld_msg *)skb_transport_header(skb);
1648
1649         switch (mld->mld_type) {
1650         case ICMPV6_MGM_REPORT:
1651                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1652                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1653                 break;
1654         case ICMPV6_MLD2_REPORT:
1655                 err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
1656                 break;
1657         case ICMPV6_MGM_QUERY:
1658                 err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
1659                 break;
1660         case ICMPV6_MGM_REDUCTION:
1661                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1662                 break;
1663         }
1664
1665         if (skb_trimmed && skb_trimmed != skb)
1666                 kfree_skb(skb_trimmed);
1667
1668         return err;
1669 }
1670 #endif
1671
1672 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1673                      struct sk_buff *skb, u16 vid)
1674 {
1675         BR_INPUT_SKB_CB(skb)->igmp = 0;
1676         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1677
1678         if (br->multicast_disabled)
1679                 return 0;
1680
1681         switch (skb->protocol) {
1682         case htons(ETH_P_IP):
1683                 return br_multicast_ipv4_rcv(br, port, skb, vid);
1684 #if IS_ENABLED(CONFIG_IPV6)
1685         case htons(ETH_P_IPV6):
1686                 return br_multicast_ipv6_rcv(br, port, skb, vid);
1687 #endif
1688         }
1689
1690         return 0;
1691 }
1692
1693 static void br_multicast_query_expired(struct net_bridge *br,
1694                                        struct bridge_mcast_own_query *query,
1695                                        struct bridge_mcast_querier *querier)
1696 {
1697         spin_lock(&br->multicast_lock);
1698         if (query->startup_sent < br->multicast_startup_query_count)
1699                 query->startup_sent++;
1700
1701         RCU_INIT_POINTER(querier->port, NULL);
1702         br_multicast_send_query(br, NULL, query);
1703         spin_unlock(&br->multicast_lock);
1704 }
1705
1706 static void br_ip4_multicast_query_expired(unsigned long data)
1707 {
1708         struct net_bridge *br = (void *)data;
1709
1710         br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1711 }
1712
1713 #if IS_ENABLED(CONFIG_IPV6)
1714 static void br_ip6_multicast_query_expired(unsigned long data)
1715 {
1716         struct net_bridge *br = (void *)data;
1717
1718         br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1719 }
1720 #endif
1721
1722 void br_multicast_init(struct net_bridge *br)
1723 {
1724         br->hash_elasticity = 4;
1725         br->hash_max = 512;
1726
1727         br->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
1728         br->multicast_querier = 0;
1729         br->multicast_query_use_ifaddr = 0;
1730         br->multicast_last_member_count = 2;
1731         br->multicast_startup_query_count = 2;
1732
1733         br->multicast_last_member_interval = HZ;
1734         br->multicast_query_response_interval = 10 * HZ;
1735         br->multicast_startup_query_interval = 125 * HZ / 4;
1736         br->multicast_query_interval = 125 * HZ;
1737         br->multicast_querier_interval = 255 * HZ;
1738         br->multicast_membership_interval = 260 * HZ;
1739
1740         br->ip4_other_query.delay_time = 0;
1741         br->ip4_querier.port = NULL;
1742 #if IS_ENABLED(CONFIG_IPV6)
1743         br->ip6_other_query.delay_time = 0;
1744         br->ip6_querier.port = NULL;
1745 #endif
1746
1747         spin_lock_init(&br->multicast_lock);
1748         setup_timer(&br->multicast_router_timer,
1749                     br_multicast_local_router_expired, 0);
1750         setup_timer(&br->ip4_other_query.timer,
1751                     br_ip4_multicast_querier_expired, (unsigned long)br);
1752         setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1753                     (unsigned long)br);
1754 #if IS_ENABLED(CONFIG_IPV6)
1755         setup_timer(&br->ip6_other_query.timer,
1756                     br_ip6_multicast_querier_expired, (unsigned long)br);
1757         setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1758                     (unsigned long)br);
1759 #endif
1760 }
1761
1762 static void __br_multicast_open(struct net_bridge *br,
1763                                 struct bridge_mcast_own_query *query)
1764 {
1765         query->startup_sent = 0;
1766
1767         if (br->multicast_disabled)
1768                 return;
1769
1770         mod_timer(&query->timer, jiffies);
1771 }
1772
1773 void br_multicast_open(struct net_bridge *br)
1774 {
1775         __br_multicast_open(br, &br->ip4_own_query);
1776 #if IS_ENABLED(CONFIG_IPV6)
1777         __br_multicast_open(br, &br->ip6_own_query);
1778 #endif
1779 }
1780
1781 void br_multicast_stop(struct net_bridge *br)
1782 {
1783         del_timer_sync(&br->multicast_router_timer);
1784         del_timer_sync(&br->ip4_other_query.timer);
1785         del_timer_sync(&br->ip4_own_query.timer);
1786 #if IS_ENABLED(CONFIG_IPV6)
1787         del_timer_sync(&br->ip6_other_query.timer);
1788         del_timer_sync(&br->ip6_own_query.timer);
1789 #endif
1790 }
1791
1792 void br_multicast_dev_del(struct net_bridge *br)
1793 {
1794         struct net_bridge_mdb_htable *mdb;
1795         struct net_bridge_mdb_entry *mp;
1796         struct hlist_node *n;
1797         u32 ver;
1798         int i;
1799
1800         spin_lock_bh(&br->multicast_lock);
1801         mdb = mlock_dereference(br->mdb, br);
1802         if (!mdb)
1803                 goto out;
1804
1805         br->mdb = NULL;
1806
1807         ver = mdb->ver;
1808         for (i = 0; i < mdb->max; i++) {
1809                 hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1810                                           hlist[ver]) {
1811                         del_timer(&mp->timer);
1812                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1813                 }
1814         }
1815
1816         if (mdb->old) {
1817                 spin_unlock_bh(&br->multicast_lock);
1818                 rcu_barrier_bh();
1819                 spin_lock_bh(&br->multicast_lock);
1820                 WARN_ON(mdb->old);
1821         }
1822
1823         mdb->old = mdb;
1824         call_rcu_bh(&mdb->rcu, br_mdb_free);
1825
1826 out:
1827         spin_unlock_bh(&br->multicast_lock);
1828 }
1829
1830 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1831 {
1832         int err = -EINVAL;
1833
1834         spin_lock_bh(&br->multicast_lock);
1835
1836         switch (val) {
1837         case MDB_RTR_TYPE_DISABLED:
1838         case MDB_RTR_TYPE_PERM:
1839                 del_timer(&br->multicast_router_timer);
1840                 /* fall through */
1841         case MDB_RTR_TYPE_TEMP_QUERY:
1842                 br->multicast_router = val;
1843                 err = 0;
1844                 break;
1845         }
1846
1847         spin_unlock_bh(&br->multicast_lock);
1848
1849         return err;
1850 }
1851
1852 static void __del_port_router(struct net_bridge_port *p)
1853 {
1854         if (hlist_unhashed(&p->rlist))
1855                 return;
1856         hlist_del_init_rcu(&p->rlist);
1857         br_rtr_notify(p->br->dev, p, RTM_DELMDB);
1858 }
1859
1860 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1861 {
1862         struct net_bridge *br = p->br;
1863         unsigned long now = jiffies;
1864         int err = -EINVAL;
1865
1866         spin_lock(&br->multicast_lock);
1867         if (p->multicast_router == val) {
1868                 /* Refresh the temp router port timer */
1869                 if (p->multicast_router == MDB_RTR_TYPE_TEMP)
1870                         mod_timer(&p->multicast_router_timer,
1871                                   now + br->multicast_querier_interval);
1872                 err = 0;
1873                 goto unlock;
1874         }
1875         switch (val) {
1876         case MDB_RTR_TYPE_DISABLED:
1877                 p->multicast_router = MDB_RTR_TYPE_DISABLED;
1878                 __del_port_router(p);
1879                 del_timer(&p->multicast_router_timer);
1880                 break;
1881         case MDB_RTR_TYPE_TEMP_QUERY:
1882                 p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
1883                 __del_port_router(p);
1884                 break;
1885         case MDB_RTR_TYPE_PERM:
1886                 p->multicast_router = MDB_RTR_TYPE_PERM;
1887                 del_timer(&p->multicast_router_timer);
1888                 br_multicast_add_router(br, p);
1889                 break;
1890         case MDB_RTR_TYPE_TEMP:
1891                 p->multicast_router = MDB_RTR_TYPE_TEMP;
1892                 br_multicast_mark_router(br, p);
1893                 break;
1894         default:
1895                 goto unlock;
1896         }
1897         err = 0;
1898 unlock:
1899         spin_unlock(&br->multicast_lock);
1900
1901         return err;
1902 }
1903
1904 static void br_multicast_start_querier(struct net_bridge *br,
1905                                        struct bridge_mcast_own_query *query)
1906 {
1907         struct net_bridge_port *port;
1908
1909         __br_multicast_open(br, query);
1910
1911         list_for_each_entry(port, &br->port_list, list) {
1912                 if (port->state == BR_STATE_DISABLED ||
1913                     port->state == BR_STATE_BLOCKING)
1914                         continue;
1915
1916                 if (query == &br->ip4_own_query)
1917                         br_multicast_enable(&port->ip4_own_query);
1918 #if IS_ENABLED(CONFIG_IPV6)
1919                 else
1920                         br_multicast_enable(&port->ip6_own_query);
1921 #endif
1922         }
1923 }
1924
1925 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1926 {
1927         int err = 0;
1928         struct net_bridge_mdb_htable *mdb;
1929
1930         spin_lock_bh(&br->multicast_lock);
1931         if (br->multicast_disabled == !val)
1932                 goto unlock;
1933
1934         br->multicast_disabled = !val;
1935         if (br->multicast_disabled)
1936                 goto unlock;
1937
1938         if (!netif_running(br->dev))
1939                 goto unlock;
1940
1941         mdb = mlock_dereference(br->mdb, br);
1942         if (mdb) {
1943                 if (mdb->old) {
1944                         err = -EEXIST;
1945 rollback:
1946                         br->multicast_disabled = !!val;
1947                         goto unlock;
1948                 }
1949
1950                 err = br_mdb_rehash(&br->mdb, mdb->max,
1951                                     br->hash_elasticity);
1952                 if (err)
1953                         goto rollback;
1954         }
1955
1956         br_multicast_start_querier(br, &br->ip4_own_query);
1957 #if IS_ENABLED(CONFIG_IPV6)
1958         br_multicast_start_querier(br, &br->ip6_own_query);
1959 #endif
1960
1961 unlock:
1962         spin_unlock_bh(&br->multicast_lock);
1963
1964         return err;
1965 }
1966
1967 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1968 {
1969         unsigned long max_delay;
1970
1971         val = !!val;
1972
1973         spin_lock_bh(&br->multicast_lock);
1974         if (br->multicast_querier == val)
1975                 goto unlock;
1976
1977         br->multicast_querier = val;
1978         if (!val)
1979                 goto unlock;
1980
1981         max_delay = br->multicast_query_response_interval;
1982
1983         if (!timer_pending(&br->ip4_other_query.timer))
1984                 br->ip4_other_query.delay_time = jiffies + max_delay;
1985
1986         br_multicast_start_querier(br, &br->ip4_own_query);
1987
1988 #if IS_ENABLED(CONFIG_IPV6)
1989         if (!timer_pending(&br->ip6_other_query.timer))
1990                 br->ip6_other_query.delay_time = jiffies + max_delay;
1991
1992         br_multicast_start_querier(br, &br->ip6_own_query);
1993 #endif
1994
1995 unlock:
1996         spin_unlock_bh(&br->multicast_lock);
1997
1998         return 0;
1999 }
2000
2001 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2002 {
2003         int err = -EINVAL;
2004         u32 old;
2005         struct net_bridge_mdb_htable *mdb;
2006
2007         spin_lock_bh(&br->multicast_lock);
2008         if (!is_power_of_2(val))
2009                 goto unlock;
2010
2011         mdb = mlock_dereference(br->mdb, br);
2012         if (mdb && val < mdb->size)
2013                 goto unlock;
2014
2015         err = 0;
2016
2017         old = br->hash_max;
2018         br->hash_max = val;
2019
2020         if (mdb) {
2021                 if (mdb->old) {
2022                         err = -EEXIST;
2023 rollback:
2024                         br->hash_max = old;
2025                         goto unlock;
2026                 }
2027
2028                 err = br_mdb_rehash(&br->mdb, br->hash_max,
2029                                     br->hash_elasticity);
2030                 if (err)
2031                         goto rollback;
2032         }
2033
2034 unlock:
2035         spin_unlock_bh(&br->multicast_lock);
2036
2037         return err;
2038 }
2039
2040 /**
2041  * br_multicast_list_adjacent - Returns snooped multicast addresses
2042  * @dev:        The bridge port adjacent to which to retrieve addresses
2043  * @br_ip_list: The list to store found, snooped multicast IP addresses in
2044  *
2045  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2046  * snooping feature on all bridge ports of dev's bridge device, excluding
2047  * the addresses from dev itself.
2048  *
2049  * Returns the number of items added to br_ip_list.
2050  *
2051  * Notes:
2052  * - br_ip_list needs to be initialized by caller
2053  * - br_ip_list might contain duplicates in the end
2054  *   (needs to be taken care of by caller)
2055  * - br_ip_list needs to be freed by caller
2056  */
2057 int br_multicast_list_adjacent(struct net_device *dev,
2058                                struct list_head *br_ip_list)
2059 {
2060         struct net_bridge *br;
2061         struct net_bridge_port *port;
2062         struct net_bridge_port_group *group;
2063         struct br_ip_list *entry;
2064         int count = 0;
2065
2066         rcu_read_lock();
2067         if (!br_ip_list || !br_port_exists(dev))
2068                 goto unlock;
2069
2070         port = br_port_get_rcu(dev);
2071         if (!port || !port->br)
2072                 goto unlock;
2073
2074         br = port->br;
2075
2076         list_for_each_entry_rcu(port, &br->port_list, list) {
2077                 if (!port->dev || port->dev == dev)
2078                         continue;
2079
2080                 hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2081                         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2082                         if (!entry)
2083                                 goto unlock;
2084
2085                         entry->addr = group->addr;
2086                         list_add(&entry->list, br_ip_list);
2087                         count++;
2088                 }
2089         }
2090
2091 unlock:
2092         rcu_read_unlock();
2093         return count;
2094 }
2095 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2096
2097 /**
2098  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2099  * @dev: The bridge port providing the bridge on which to check for a querier
2100  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2101  *
2102  * Checks whether the given interface has a bridge on top and if so returns
2103  * true if a valid querier exists anywhere on the bridged link layer.
2104  * Otherwise returns false.
2105  */
2106 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2107 {
2108         struct net_bridge *br;
2109         struct net_bridge_port *port;
2110         struct ethhdr eth;
2111         bool ret = false;
2112
2113         rcu_read_lock();
2114         if (!br_port_exists(dev))
2115                 goto unlock;
2116
2117         port = br_port_get_rcu(dev);
2118         if (!port || !port->br)
2119                 goto unlock;
2120
2121         br = port->br;
2122
2123         memset(&eth, 0, sizeof(eth));
2124         eth.h_proto = htons(proto);
2125
2126         ret = br_multicast_querier_exists(br, &eth);
2127
2128 unlock:
2129         rcu_read_unlock();
2130         return ret;
2131 }
2132 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2133
2134 /**
2135  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2136  * @dev: The bridge port adjacent to which to check for a querier
2137  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2138  *
2139  * Checks whether the given interface has a bridge on top and if so returns
2140  * true if a selected querier is behind one of the other ports of this
2141  * bridge. Otherwise returns false.
2142  */
2143 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2144 {
2145         struct net_bridge *br;
2146         struct net_bridge_port *port;
2147         bool ret = false;
2148
2149         rcu_read_lock();
2150         if (!br_port_exists(dev))
2151                 goto unlock;
2152
2153         port = br_port_get_rcu(dev);
2154         if (!port || !port->br)
2155                 goto unlock;
2156
2157         br = port->br;
2158
2159         switch (proto) {
2160         case ETH_P_IP:
2161                 if (!timer_pending(&br->ip4_other_query.timer) ||
2162                     rcu_dereference(br->ip4_querier.port) == port)
2163                         goto unlock;
2164                 break;
2165 #if IS_ENABLED(CONFIG_IPV6)
2166         case ETH_P_IPV6:
2167                 if (!timer_pending(&br->ip6_other_query.timer) ||
2168                     rcu_dereference(br->ip6_querier.port) == port)
2169                         goto unlock;
2170                 break;
2171 #endif
2172         default:
2173                 goto unlock;
2174         }
2175
2176         ret = true;
2177 unlock:
2178         rcu_read_unlock();
2179         return ret;
2180 }
2181 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);