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