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