Merge tag 'md/4.2-fixes' of git://neil.brown.name/md
[platform/kernel/linux-rpi.git] / net / bridge / br_multicast.c
1 /*
2  * Bridge multicast support.
3  *
4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/if_ether.h>
16 #include <linux/igmp.h>
17 #include <linux/jhash.h>
18 #include <linux/kernel.h>
19 #include <linux/log2.h>
20 #include <linux/netdevice.h>
21 #include <linux/netfilter_bridge.h>
22 #include <linux/random.h>
23 #include <linux/rculist.h>
24 #include <linux/skbuff.h>
25 #include <linux/slab.h>
26 #include <linux/timer.h>
27 #include <linux/inetdevice.h>
28 #include <net/ip.h>
29 #if IS_ENABLED(CONFIG_IPV6)
30 #include <net/ipv6.h>
31 #include <net/mld.h>
32 #include <net/ip6_checksum.h>
33 #include <net/addrconf.h>
34 #endif
35
36 #include "br_private.h"
37
38 static void br_multicast_start_querier(struct net_bridge *br,
39                                        struct bridge_mcast_own_query *query);
40 static void br_multicast_add_router(struct net_bridge *br,
41                                     struct net_bridge_port *port);
42 static void br_ip4_multicast_leave_group(struct net_bridge *br,
43                                          struct net_bridge_port *port,
44                                          __be32 group,
45                                          __u16 vid);
46 #if IS_ENABLED(CONFIG_IPV6)
47 static void br_ip6_multicast_leave_group(struct net_bridge *br,
48                                          struct net_bridge_port *port,
49                                          const struct in6_addr *group,
50                                          __u16 vid);
51 #endif
52 unsigned int br_mdb_rehash_seq;
53
54 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
55 {
56         if (a->proto != b->proto)
57                 return 0;
58         if (a->vid != b->vid)
59                 return 0;
60         switch (a->proto) {
61         case htons(ETH_P_IP):
62                 return a->u.ip4 == b->u.ip4;
63 #if IS_ENABLED(CONFIG_IPV6)
64         case htons(ETH_P_IPV6):
65                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
66 #endif
67         }
68         return 0;
69 }
70
71 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
72                                 __u16 vid)
73 {
74         return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
75 }
76
77 #if IS_ENABLED(CONFIG_IPV6)
78 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
79                                 const struct in6_addr *ip,
80                                 __u16 vid)
81 {
82         return jhash_2words(ipv6_addr_hash(ip), vid,
83                             mdb->secret) & (mdb->max - 1);
84 }
85 #endif
86
87 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
88                              struct br_ip *ip)
89 {
90         switch (ip->proto) {
91         case htons(ETH_P_IP):
92                 return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
93 #if IS_ENABLED(CONFIG_IPV6)
94         case htons(ETH_P_IPV6):
95                 return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
96 #endif
97         }
98         return 0;
99 }
100
101 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
102         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
103 {
104         struct net_bridge_mdb_entry *mp;
105
106         hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
107                 if (br_ip_equal(&mp->addr, dst))
108                         return mp;
109         }
110
111         return NULL;
112 }
113
114 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
115                                            struct br_ip *dst)
116 {
117         if (!mdb)
118                 return NULL;
119
120         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
121 }
122
123 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
124         struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
125 {
126         struct br_ip br_dst;
127
128         br_dst.u.ip4 = dst;
129         br_dst.proto = htons(ETH_P_IP);
130         br_dst.vid = vid;
131
132         return br_mdb_ip_get(mdb, &br_dst);
133 }
134
135 #if IS_ENABLED(CONFIG_IPV6)
136 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
137         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
138         __u16 vid)
139 {
140         struct br_ip br_dst;
141
142         br_dst.u.ip6 = *dst;
143         br_dst.proto = htons(ETH_P_IPV6);
144         br_dst.vid = vid;
145
146         return br_mdb_ip_get(mdb, &br_dst);
147 }
148 #endif
149
150 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
151                                         struct sk_buff *skb, u16 vid)
152 {
153         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
154         struct br_ip ip;
155
156         if (br->multicast_disabled)
157                 return NULL;
158
159         if (BR_INPUT_SKB_CB(skb)->igmp)
160                 return NULL;
161
162         ip.proto = skb->protocol;
163         ip.vid = vid;
164
165         switch (skb->protocol) {
166         case htons(ETH_P_IP):
167                 ip.u.ip4 = ip_hdr(skb)->daddr;
168                 break;
169 #if IS_ENABLED(CONFIG_IPV6)
170         case htons(ETH_P_IPV6):
171                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
172                 break;
173 #endif
174         default:
175                 return NULL;
176         }
177
178         return br_mdb_ip_get(mdb, &ip);
179 }
180
181 static void br_mdb_free(struct rcu_head *head)
182 {
183         struct net_bridge_mdb_htable *mdb =
184                 container_of(head, struct net_bridge_mdb_htable, rcu);
185         struct net_bridge_mdb_htable *old = mdb->old;
186
187         mdb->old = NULL;
188         kfree(old->mhash);
189         kfree(old);
190 }
191
192 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
193                        struct net_bridge_mdb_htable *old,
194                        int elasticity)
195 {
196         struct net_bridge_mdb_entry *mp;
197         int maxlen;
198         int len;
199         int i;
200
201         for (i = 0; i < old->max; i++)
202                 hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
203                         hlist_add_head(&mp->hlist[new->ver],
204                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
205
206         if (!elasticity)
207                 return 0;
208
209         maxlen = 0;
210         for (i = 0; i < new->max; i++) {
211                 len = 0;
212                 hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
213                         len++;
214                 if (len > maxlen)
215                         maxlen = len;
216         }
217
218         return maxlen > elasticity ? -EINVAL : 0;
219 }
220
221 void br_multicast_free_pg(struct rcu_head *head)
222 {
223         struct net_bridge_port_group *p =
224                 container_of(head, struct net_bridge_port_group, rcu);
225
226         kfree(p);
227 }
228
229 static void br_multicast_free_group(struct rcu_head *head)
230 {
231         struct net_bridge_mdb_entry *mp =
232                 container_of(head, struct net_bridge_mdb_entry, rcu);
233
234         kfree(mp);
235 }
236
237 static void br_multicast_group_expired(unsigned long data)
238 {
239         struct net_bridge_mdb_entry *mp = (void *)data;
240         struct net_bridge *br = mp->br;
241         struct net_bridge_mdb_htable *mdb;
242
243         spin_lock(&br->multicast_lock);
244         if (!netif_running(br->dev) || timer_pending(&mp->timer))
245                 goto out;
246
247         mp->mglist = false;
248
249         if (mp->ports)
250                 goto out;
251
252         mdb = mlock_dereference(br->mdb, br);
253
254         hlist_del_rcu(&mp->hlist[mdb->ver]);
255         mdb->size--;
256
257         call_rcu_bh(&mp->rcu, br_multicast_free_group);
258
259 out:
260         spin_unlock(&br->multicast_lock);
261 }
262
263 static void br_multicast_del_pg(struct net_bridge *br,
264                                 struct net_bridge_port_group *pg)
265 {
266         struct net_bridge_mdb_htable *mdb;
267         struct net_bridge_mdb_entry *mp;
268         struct net_bridge_port_group *p;
269         struct net_bridge_port_group __rcu **pp;
270
271         mdb = mlock_dereference(br->mdb, br);
272
273         mp = br_mdb_ip_get(mdb, &pg->addr);
274         if (WARN_ON(!mp))
275                 return;
276
277         for (pp = &mp->ports;
278              (p = mlock_dereference(*pp, br)) != NULL;
279              pp = &p->next) {
280                 if (p != pg)
281                         continue;
282
283                 rcu_assign_pointer(*pp, p->next);
284                 hlist_del_init(&p->mglist);
285                 del_timer(&p->timer);
286                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
287
288                 if (!mp->ports && !mp->mglist &&
289                     netif_running(br->dev))
290                         mod_timer(&mp->timer, jiffies);
291
292                 return;
293         }
294
295         WARN_ON(1);
296 }
297
298 static void br_multicast_port_group_expired(unsigned long data)
299 {
300         struct net_bridge_port_group *pg = (void *)data;
301         struct net_bridge *br = pg->port->br;
302
303         spin_lock(&br->multicast_lock);
304         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
305             hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
306                 goto out;
307
308         br_multicast_del_pg(br, pg);
309
310 out:
311         spin_unlock(&br->multicast_lock);
312 }
313
314 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
315                          int elasticity)
316 {
317         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
318         struct net_bridge_mdb_htable *mdb;
319         int err;
320
321         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
322         if (!mdb)
323                 return -ENOMEM;
324
325         mdb->max = max;
326         mdb->old = old;
327
328         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
329         if (!mdb->mhash) {
330                 kfree(mdb);
331                 return -ENOMEM;
332         }
333
334         mdb->size = old ? old->size : 0;
335         mdb->ver = old ? old->ver ^ 1 : 0;
336
337         if (!old || elasticity)
338                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
339         else
340                 mdb->secret = old->secret;
341
342         if (!old)
343                 goto out;
344
345         err = br_mdb_copy(mdb, old, elasticity);
346         if (err) {
347                 kfree(mdb->mhash);
348                 kfree(mdb);
349                 return err;
350         }
351
352         br_mdb_rehash_seq++;
353         call_rcu_bh(&mdb->rcu, br_mdb_free);
354
355 out:
356         rcu_assign_pointer(*mdbp, mdb);
357
358         return 0;
359 }
360
361 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
362                                                     __be32 group)
363 {
364         struct sk_buff *skb;
365         struct igmphdr *ih;
366         struct ethhdr *eth;
367         struct iphdr *iph;
368
369         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
370                                                  sizeof(*ih) + 4);
371         if (!skb)
372                 goto out;
373
374         skb->protocol = htons(ETH_P_IP);
375
376         skb_reset_mac_header(skb);
377         eth = eth_hdr(skb);
378
379         ether_addr_copy(eth->h_source, br->dev->dev_addr);
380         eth->h_dest[0] = 1;
381         eth->h_dest[1] = 0;
382         eth->h_dest[2] = 0x5e;
383         eth->h_dest[3] = 0;
384         eth->h_dest[4] = 0;
385         eth->h_dest[5] = 1;
386         eth->h_proto = htons(ETH_P_IP);
387         skb_put(skb, sizeof(*eth));
388
389         skb_set_network_header(skb, skb->len);
390         iph = ip_hdr(skb);
391
392         iph->version = 4;
393         iph->ihl = 6;
394         iph->tos = 0xc0;
395         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
396         iph->id = 0;
397         iph->frag_off = htons(IP_DF);
398         iph->ttl = 1;
399         iph->protocol = IPPROTO_IGMP;
400         iph->saddr = br->multicast_query_use_ifaddr ?
401                      inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
402         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
403         ((u8 *)&iph[1])[0] = IPOPT_RA;
404         ((u8 *)&iph[1])[1] = 4;
405         ((u8 *)&iph[1])[2] = 0;
406         ((u8 *)&iph[1])[3] = 0;
407         ip_send_check(iph);
408         skb_put(skb, 24);
409
410         skb_set_transport_header(skb, skb->len);
411         ih = igmp_hdr(skb);
412         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
413         ih->code = (group ? br->multicast_last_member_interval :
414                             br->multicast_query_response_interval) /
415                    (HZ / IGMP_TIMER_SCALE);
416         ih->group = group;
417         ih->csum = 0;
418         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
419         skb_put(skb, sizeof(*ih));
420
421         __skb_pull(skb, sizeof(*eth));
422
423 out:
424         return skb;
425 }
426
427 #if IS_ENABLED(CONFIG_IPV6)
428 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
429                                                     const struct in6_addr *group)
430 {
431         struct sk_buff *skb;
432         struct ipv6hdr *ip6h;
433         struct mld_msg *mldq;
434         struct ethhdr *eth;
435         u8 *hopopt;
436         unsigned long interval;
437
438         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
439                                                  8 + sizeof(*mldq));
440         if (!skb)
441                 goto out;
442
443         skb->protocol = htons(ETH_P_IPV6);
444
445         /* Ethernet header */
446         skb_reset_mac_header(skb);
447         eth = eth_hdr(skb);
448
449         ether_addr_copy(eth->h_source, br->dev->dev_addr);
450         eth->h_proto = htons(ETH_P_IPV6);
451         skb_put(skb, sizeof(*eth));
452
453         /* IPv6 header + HbH option */
454         skb_set_network_header(skb, skb->len);
455         ip6h = ipv6_hdr(skb);
456
457         *(__force __be32 *)ip6h = htonl(0x60000000);
458         ip6h->payload_len = htons(8 + sizeof(*mldq));
459         ip6h->nexthdr = IPPROTO_HOPOPTS;
460         ip6h->hop_limit = 1;
461         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
462         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
463                                &ip6h->saddr)) {
464                 kfree_skb(skb);
465                 return NULL;
466         }
467         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
468
469         hopopt = (u8 *)(ip6h + 1);
470         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
471         hopopt[1] = 0;                          /* length of HbH */
472         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
473         hopopt[3] = 2;                          /* Length of RA Option */
474         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
475         hopopt[5] = 0;
476         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
477         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
478
479         skb_put(skb, sizeof(*ip6h) + 8);
480
481         /* ICMPv6 */
482         skb_set_transport_header(skb, skb->len);
483         mldq = (struct mld_msg *) icmp6_hdr(skb);
484
485         interval = ipv6_addr_any(group) ?
486                         br->multicast_query_response_interval :
487                         br->multicast_last_member_interval;
488
489         mldq->mld_type = ICMPV6_MGM_QUERY;
490         mldq->mld_code = 0;
491         mldq->mld_cksum = 0;
492         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
493         mldq->mld_reserved = 0;
494         mldq->mld_mca = *group;
495
496         /* checksum */
497         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
498                                           sizeof(*mldq), IPPROTO_ICMPV6,
499                                           csum_partial(mldq,
500                                                        sizeof(*mldq), 0));
501         skb_put(skb, sizeof(*mldq));
502
503         __skb_pull(skb, sizeof(*eth));
504
505 out:
506         return skb;
507 }
508 #endif
509
510 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
511                                                 struct br_ip *addr)
512 {
513         switch (addr->proto) {
514         case htons(ETH_P_IP):
515                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
516 #if IS_ENABLED(CONFIG_IPV6)
517         case htons(ETH_P_IPV6):
518                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
519 #endif
520         }
521         return NULL;
522 }
523
524 static struct net_bridge_mdb_entry *br_multicast_get_group(
525         struct net_bridge *br, struct net_bridge_port *port,
526         struct br_ip *group, int hash)
527 {
528         struct net_bridge_mdb_htable *mdb;
529         struct net_bridge_mdb_entry *mp;
530         unsigned int count = 0;
531         unsigned int max;
532         int elasticity;
533         int err;
534
535         mdb = rcu_dereference_protected(br->mdb, 1);
536         hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
537                 count++;
538                 if (unlikely(br_ip_equal(group, &mp->addr)))
539                         return mp;
540         }
541
542         elasticity = 0;
543         max = mdb->max;
544
545         if (unlikely(count > br->hash_elasticity && count)) {
546                 if (net_ratelimit())
547                         br_info(br, "Multicast hash table "
548                                 "chain limit reached: %s\n",
549                                 port ? port->dev->name : br->dev->name);
550
551                 elasticity = br->hash_elasticity;
552         }
553
554         if (mdb->size >= max) {
555                 max *= 2;
556                 if (unlikely(max > br->hash_max)) {
557                         br_warn(br, "Multicast hash table maximum of %d "
558                                 "reached, disabling snooping: %s\n",
559                                 br->hash_max,
560                                 port ? port->dev->name : br->dev->name);
561                         err = -E2BIG;
562 disable:
563                         br->multicast_disabled = 1;
564                         goto err;
565                 }
566         }
567
568         if (max > mdb->max || elasticity) {
569                 if (mdb->old) {
570                         if (net_ratelimit())
571                                 br_info(br, "Multicast hash table "
572                                         "on fire: %s\n",
573                                         port ? port->dev->name : br->dev->name);
574                         err = -EEXIST;
575                         goto err;
576                 }
577
578                 err = br_mdb_rehash(&br->mdb, max, elasticity);
579                 if (err) {
580                         br_warn(br, "Cannot rehash multicast "
581                                 "hash table, disabling snooping: %s, %d, %d\n",
582                                 port ? port->dev->name : br->dev->name,
583                                 mdb->size, err);
584                         goto disable;
585                 }
586
587                 err = -EAGAIN;
588                 goto err;
589         }
590
591         return NULL;
592
593 err:
594         mp = ERR_PTR(err);
595         return mp;
596 }
597
598 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
599         struct net_bridge_port *port, struct br_ip *group)
600 {
601         struct net_bridge_mdb_htable *mdb;
602         struct net_bridge_mdb_entry *mp;
603         int hash;
604         int err;
605
606         mdb = rcu_dereference_protected(br->mdb, 1);
607         if (!mdb) {
608                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
609                 if (err)
610                         return ERR_PTR(err);
611                 goto rehash;
612         }
613
614         hash = br_ip_hash(mdb, group);
615         mp = br_multicast_get_group(br, port, group, hash);
616         switch (PTR_ERR(mp)) {
617         case 0:
618                 break;
619
620         case -EAGAIN:
621 rehash:
622                 mdb = rcu_dereference_protected(br->mdb, 1);
623                 hash = br_ip_hash(mdb, group);
624                 break;
625
626         default:
627                 goto out;
628         }
629
630         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
631         if (unlikely(!mp))
632                 return ERR_PTR(-ENOMEM);
633
634         mp->br = br;
635         mp->addr = *group;
636         setup_timer(&mp->timer, br_multicast_group_expired,
637                     (unsigned long)mp);
638
639         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
640         mdb->size++;
641
642 out:
643         return mp;
644 }
645
646 struct net_bridge_port_group *br_multicast_new_port_group(
647                         struct net_bridge_port *port,
648                         struct br_ip *group,
649                         struct net_bridge_port_group __rcu *next,
650                         unsigned char state)
651 {
652         struct net_bridge_port_group *p;
653
654         p = kzalloc(sizeof(*p), GFP_ATOMIC);
655         if (unlikely(!p))
656                 return NULL;
657
658         p->addr = *group;
659         p->port = port;
660         p->state = state;
661         rcu_assign_pointer(p->next, next);
662         hlist_add_head(&p->mglist, &port->mglist);
663         setup_timer(&p->timer, br_multicast_port_group_expired,
664                     (unsigned long)p);
665         return p;
666 }
667
668 static int br_multicast_add_group(struct net_bridge *br,
669                                   struct net_bridge_port *port,
670                                   struct br_ip *group)
671 {
672         struct net_bridge_mdb_entry *mp;
673         struct net_bridge_port_group *p;
674         struct net_bridge_port_group __rcu **pp;
675         unsigned long now = jiffies;
676         int err;
677
678         spin_lock(&br->multicast_lock);
679         if (!netif_running(br->dev) ||
680             (port && port->state == BR_STATE_DISABLED))
681                 goto out;
682
683         mp = br_multicast_new_group(br, port, group);
684         err = PTR_ERR(mp);
685         if (IS_ERR(mp))
686                 goto err;
687
688         if (!port) {
689                 mp->mglist = true;
690                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
691                 goto out;
692         }
693
694         for (pp = &mp->ports;
695              (p = mlock_dereference(*pp, br)) != NULL;
696              pp = &p->next) {
697                 if (p->port == port)
698                         goto found;
699                 if ((unsigned long)p->port < (unsigned long)port)
700                         break;
701         }
702
703         p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
704         if (unlikely(!p))
705                 goto err;
706         rcu_assign_pointer(*pp, p);
707         br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
708
709 found:
710         mod_timer(&p->timer, now + br->multicast_membership_interval);
711 out:
712         err = 0;
713
714 err:
715         spin_unlock(&br->multicast_lock);
716         return err;
717 }
718
719 static int br_ip4_multicast_add_group(struct net_bridge *br,
720                                       struct net_bridge_port *port,
721                                       __be32 group,
722                                       __u16 vid)
723 {
724         struct br_ip br_group;
725
726         if (ipv4_is_local_multicast(group))
727                 return 0;
728
729         br_group.u.ip4 = group;
730         br_group.proto = htons(ETH_P_IP);
731         br_group.vid = vid;
732
733         return br_multicast_add_group(br, port, &br_group);
734 }
735
736 #if IS_ENABLED(CONFIG_IPV6)
737 static int br_ip6_multicast_add_group(struct net_bridge *br,
738                                       struct net_bridge_port *port,
739                                       const struct in6_addr *group,
740                                       __u16 vid)
741 {
742         struct br_ip br_group;
743
744         if (ipv6_addr_is_ll_all_nodes(group))
745                 return 0;
746
747         br_group.u.ip6 = *group;
748         br_group.proto = htons(ETH_P_IPV6);
749         br_group.vid = vid;
750
751         return br_multicast_add_group(br, port, &br_group);
752 }
753 #endif
754
755 static void br_multicast_router_expired(unsigned long data)
756 {
757         struct net_bridge_port *port = (void *)data;
758         struct net_bridge *br = port->br;
759
760         spin_lock(&br->multicast_lock);
761         if (port->multicast_router != 1 ||
762             timer_pending(&port->multicast_router_timer) ||
763             hlist_unhashed(&port->rlist))
764                 goto out;
765
766         hlist_del_init_rcu(&port->rlist);
767
768 out:
769         spin_unlock(&br->multicast_lock);
770 }
771
772 static void br_multicast_local_router_expired(unsigned long data)
773 {
774 }
775
776 static void br_multicast_querier_expired(struct net_bridge *br,
777                                          struct bridge_mcast_own_query *query)
778 {
779         spin_lock(&br->multicast_lock);
780         if (!netif_running(br->dev) || br->multicast_disabled)
781                 goto out;
782
783         br_multicast_start_querier(br, query);
784
785 out:
786         spin_unlock(&br->multicast_lock);
787 }
788
789 static void br_ip4_multicast_querier_expired(unsigned long data)
790 {
791         struct net_bridge *br = (void *)data;
792
793         br_multicast_querier_expired(br, &br->ip4_own_query);
794 }
795
796 #if IS_ENABLED(CONFIG_IPV6)
797 static void br_ip6_multicast_querier_expired(unsigned long data)
798 {
799         struct net_bridge *br = (void *)data;
800
801         br_multicast_querier_expired(br, &br->ip6_own_query);
802 }
803 #endif
804
805 static void br_multicast_select_own_querier(struct net_bridge *br,
806                                             struct br_ip *ip,
807                                             struct sk_buff *skb)
808 {
809         if (ip->proto == htons(ETH_P_IP))
810                 br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
811 #if IS_ENABLED(CONFIG_IPV6)
812         else
813                 br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
814 #endif
815 }
816
817 static void __br_multicast_send_query(struct net_bridge *br,
818                                       struct net_bridge_port *port,
819                                       struct br_ip *ip)
820 {
821         struct sk_buff *skb;
822
823         skb = br_multicast_alloc_query(br, ip);
824         if (!skb)
825                 return;
826
827         if (port) {
828                 skb->dev = port->dev;
829                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, NULL, skb,
830                         NULL, skb->dev,
831                         br_dev_queue_push_xmit);
832         } else {
833                 br_multicast_select_own_querier(br, ip, skb);
834                 netif_rx(skb);
835         }
836 }
837
838 static void br_multicast_send_query(struct net_bridge *br,
839                                     struct net_bridge_port *port,
840                                     struct bridge_mcast_own_query *own_query)
841 {
842         unsigned long time;
843         struct br_ip br_group;
844         struct bridge_mcast_other_query *other_query = NULL;
845
846         if (!netif_running(br->dev) || br->multicast_disabled ||
847             !br->multicast_querier)
848                 return;
849
850         memset(&br_group.u, 0, sizeof(br_group.u));
851
852         if (port ? (own_query == &port->ip4_own_query) :
853                    (own_query == &br->ip4_own_query)) {
854                 other_query = &br->ip4_other_query;
855                 br_group.proto = htons(ETH_P_IP);
856 #if IS_ENABLED(CONFIG_IPV6)
857         } else {
858                 other_query = &br->ip6_other_query;
859                 br_group.proto = htons(ETH_P_IPV6);
860 #endif
861         }
862
863         if (!other_query || timer_pending(&other_query->timer))
864                 return;
865
866         __br_multicast_send_query(br, port, &br_group);
867
868         time = jiffies;
869         time += own_query->startup_sent < br->multicast_startup_query_count ?
870                 br->multicast_startup_query_interval :
871                 br->multicast_query_interval;
872         mod_timer(&own_query->timer, time);
873 }
874
875 static void
876 br_multicast_port_query_expired(struct net_bridge_port *port,
877                                 struct bridge_mcast_own_query *query)
878 {
879         struct net_bridge *br = port->br;
880
881         spin_lock(&br->multicast_lock);
882         if (port->state == BR_STATE_DISABLED ||
883             port->state == BR_STATE_BLOCKING)
884                 goto out;
885
886         if (query->startup_sent < br->multicast_startup_query_count)
887                 query->startup_sent++;
888
889         br_multicast_send_query(port->br, port, query);
890
891 out:
892         spin_unlock(&br->multicast_lock);
893 }
894
895 static void br_ip4_multicast_port_query_expired(unsigned long data)
896 {
897         struct net_bridge_port *port = (void *)data;
898
899         br_multicast_port_query_expired(port, &port->ip4_own_query);
900 }
901
902 #if IS_ENABLED(CONFIG_IPV6)
903 static void br_ip6_multicast_port_query_expired(unsigned long data)
904 {
905         struct net_bridge_port *port = (void *)data;
906
907         br_multicast_port_query_expired(port, &port->ip6_own_query);
908 }
909 #endif
910
911 void br_multicast_add_port(struct net_bridge_port *port)
912 {
913         port->multicast_router = 1;
914
915         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
916                     (unsigned long)port);
917         setup_timer(&port->ip4_own_query.timer,
918                     br_ip4_multicast_port_query_expired, (unsigned long)port);
919 #if IS_ENABLED(CONFIG_IPV6)
920         setup_timer(&port->ip6_own_query.timer,
921                     br_ip6_multicast_port_query_expired, (unsigned long)port);
922 #endif
923 }
924
925 void br_multicast_del_port(struct net_bridge_port *port)
926 {
927         del_timer_sync(&port->multicast_router_timer);
928 }
929
930 static void br_multicast_enable(struct bridge_mcast_own_query *query)
931 {
932         query->startup_sent = 0;
933
934         if (try_to_del_timer_sync(&query->timer) >= 0 ||
935             del_timer(&query->timer))
936                 mod_timer(&query->timer, jiffies);
937 }
938
939 void br_multicast_enable_port(struct net_bridge_port *port)
940 {
941         struct net_bridge *br = port->br;
942
943         spin_lock(&br->multicast_lock);
944         if (br->multicast_disabled || !netif_running(br->dev))
945                 goto out;
946
947         br_multicast_enable(&port->ip4_own_query);
948 #if IS_ENABLED(CONFIG_IPV6)
949         br_multicast_enable(&port->ip6_own_query);
950 #endif
951         if (port->multicast_router == 2 && hlist_unhashed(&port->rlist))
952                 br_multicast_add_router(br, port);
953
954 out:
955         spin_unlock(&br->multicast_lock);
956 }
957
958 void br_multicast_disable_port(struct net_bridge_port *port)
959 {
960         struct net_bridge *br = port->br;
961         struct net_bridge_port_group *pg;
962         struct hlist_node *n;
963
964         spin_lock(&br->multicast_lock);
965         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
966                 br_multicast_del_pg(br, pg);
967
968         if (!hlist_unhashed(&port->rlist))
969                 hlist_del_init_rcu(&port->rlist);
970         del_timer(&port->multicast_router_timer);
971         del_timer(&port->ip4_own_query.timer);
972 #if IS_ENABLED(CONFIG_IPV6)
973         del_timer(&port->ip6_own_query.timer);
974 #endif
975         spin_unlock(&br->multicast_lock);
976 }
977
978 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
979                                          struct net_bridge_port *port,
980                                          struct sk_buff *skb,
981                                          u16 vid)
982 {
983         struct igmpv3_report *ih;
984         struct igmpv3_grec *grec;
985         int i;
986         int len;
987         int num;
988         int type;
989         int err = 0;
990         __be32 group;
991
992         ih = igmpv3_report_hdr(skb);
993         num = ntohs(ih->ngrec);
994         len = sizeof(*ih);
995
996         for (i = 0; i < num; i++) {
997                 len += sizeof(*grec);
998                 if (!pskb_may_pull(skb, len))
999                         return -EINVAL;
1000
1001                 grec = (void *)(skb->data + len - sizeof(*grec));
1002                 group = grec->grec_mca;
1003                 type = grec->grec_type;
1004
1005                 len += ntohs(grec->grec_nsrcs) * 4;
1006                 if (!pskb_may_pull(skb, len))
1007                         return -EINVAL;
1008
1009                 /* We treat this as an IGMPv2 report for now. */
1010                 switch (type) {
1011                 case IGMPV3_MODE_IS_INCLUDE:
1012                 case IGMPV3_MODE_IS_EXCLUDE:
1013                 case IGMPV3_CHANGE_TO_INCLUDE:
1014                 case IGMPV3_CHANGE_TO_EXCLUDE:
1015                 case IGMPV3_ALLOW_NEW_SOURCES:
1016                 case IGMPV3_BLOCK_OLD_SOURCES:
1017                         break;
1018
1019                 default:
1020                         continue;
1021                 }
1022
1023                 if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
1024                      type == IGMPV3_MODE_IS_INCLUDE) &&
1025                     ntohs(grec->grec_nsrcs) == 0) {
1026                         br_ip4_multicast_leave_group(br, port, group, vid);
1027                 } else {
1028                         err = br_ip4_multicast_add_group(br, port, group, vid);
1029                         if (err)
1030                                 break;
1031                 }
1032         }
1033
1034         return err;
1035 }
1036
1037 #if IS_ENABLED(CONFIG_IPV6)
1038 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1039                                         struct net_bridge_port *port,
1040                                         struct sk_buff *skb,
1041                                         u16 vid)
1042 {
1043         struct icmp6hdr *icmp6h;
1044         struct mld2_grec *grec;
1045         int i;
1046         int len;
1047         int num;
1048         int err = 0;
1049
1050         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1051                 return -EINVAL;
1052
1053         icmp6h = icmp6_hdr(skb);
1054         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1055         len = sizeof(*icmp6h);
1056
1057         for (i = 0; i < num; i++) {
1058                 __be16 *nsrcs, _nsrcs;
1059
1060                 nsrcs = skb_header_pointer(skb,
1061                                            len + offsetof(struct mld2_grec,
1062                                                           grec_nsrcs),
1063                                            sizeof(_nsrcs), &_nsrcs);
1064                 if (!nsrcs)
1065                         return -EINVAL;
1066
1067                 if (!pskb_may_pull(skb,
1068                                    len + sizeof(*grec) +
1069                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1070                         return -EINVAL;
1071
1072                 grec = (struct mld2_grec *)(skb->data + len);
1073                 len += sizeof(*grec) +
1074                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1075
1076                 /* We treat these as MLDv1 reports for now. */
1077                 switch (grec->grec_type) {
1078                 case MLD2_MODE_IS_INCLUDE:
1079                 case MLD2_MODE_IS_EXCLUDE:
1080                 case MLD2_CHANGE_TO_INCLUDE:
1081                 case MLD2_CHANGE_TO_EXCLUDE:
1082                 case MLD2_ALLOW_NEW_SOURCES:
1083                 case MLD2_BLOCK_OLD_SOURCES:
1084                         break;
1085
1086                 default:
1087                         continue;
1088                 }
1089
1090                 if ((grec->grec_type == MLD2_CHANGE_TO_INCLUDE ||
1091                      grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
1092                     ntohs(*nsrcs) == 0) {
1093                         br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
1094                                                      vid);
1095                 } else {
1096                         err = br_ip6_multicast_add_group(br, port,
1097                                                          &grec->grec_mca, vid);
1098                         if (!err)
1099                                 break;
1100                 }
1101         }
1102
1103         return err;
1104 }
1105 #endif
1106
1107 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1108                                             struct net_bridge_port *port,
1109                                             __be32 saddr)
1110 {
1111         if (!timer_pending(&br->ip4_own_query.timer) &&
1112             !timer_pending(&br->ip4_other_query.timer))
1113                 goto update;
1114
1115         if (!br->ip4_querier.addr.u.ip4)
1116                 goto update;
1117
1118         if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1119                 goto update;
1120
1121         return false;
1122
1123 update:
1124         br->ip4_querier.addr.u.ip4 = saddr;
1125
1126         /* update protected by general multicast_lock by caller */
1127         rcu_assign_pointer(br->ip4_querier.port, port);
1128
1129         return true;
1130 }
1131
1132 #if IS_ENABLED(CONFIG_IPV6)
1133 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1134                                             struct net_bridge_port *port,
1135                                             struct in6_addr *saddr)
1136 {
1137         if (!timer_pending(&br->ip6_own_query.timer) &&
1138             !timer_pending(&br->ip6_other_query.timer))
1139                 goto update;
1140
1141         if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1142                 goto update;
1143
1144         return false;
1145
1146 update:
1147         br->ip6_querier.addr.u.ip6 = *saddr;
1148
1149         /* update protected by general multicast_lock by caller */
1150         rcu_assign_pointer(br->ip6_querier.port, port);
1151
1152         return true;
1153 }
1154 #endif
1155
1156 static bool br_multicast_select_querier(struct net_bridge *br,
1157                                         struct net_bridge_port *port,
1158                                         struct br_ip *saddr)
1159 {
1160         switch (saddr->proto) {
1161         case htons(ETH_P_IP):
1162                 return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1163 #if IS_ENABLED(CONFIG_IPV6)
1164         case htons(ETH_P_IPV6):
1165                 return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1166 #endif
1167         }
1168
1169         return false;
1170 }
1171
1172 static void
1173 br_multicast_update_query_timer(struct net_bridge *br,
1174                                 struct bridge_mcast_other_query *query,
1175                                 unsigned long max_delay)
1176 {
1177         if (!timer_pending(&query->timer))
1178                 query->delay_time = jiffies + max_delay;
1179
1180         mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1181 }
1182
1183 /*
1184  * Add port to router_list
1185  *  list is maintained ordered by pointer value
1186  *  and locked by br->multicast_lock and RCU
1187  */
1188 static void br_multicast_add_router(struct net_bridge *br,
1189                                     struct net_bridge_port *port)
1190 {
1191         struct net_bridge_port *p;
1192         struct hlist_node *slot = NULL;
1193
1194         if (!hlist_unhashed(&port->rlist))
1195                 return;
1196
1197         hlist_for_each_entry(p, &br->router_list, rlist) {
1198                 if ((unsigned long) port >= (unsigned long) p)
1199                         break;
1200                 slot = &p->rlist;
1201         }
1202
1203         if (slot)
1204                 hlist_add_behind_rcu(&port->rlist, slot);
1205         else
1206                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1207 }
1208
1209 static void br_multicast_mark_router(struct net_bridge *br,
1210                                      struct net_bridge_port *port)
1211 {
1212         unsigned long now = jiffies;
1213
1214         if (!port) {
1215                 if (br->multicast_router == 1)
1216                         mod_timer(&br->multicast_router_timer,
1217                                   now + br->multicast_querier_interval);
1218                 return;
1219         }
1220
1221         if (port->multicast_router != 1)
1222                 return;
1223
1224         br_multicast_add_router(br, port);
1225
1226         mod_timer(&port->multicast_router_timer,
1227                   now + br->multicast_querier_interval);
1228 }
1229
1230 static void br_multicast_query_received(struct net_bridge *br,
1231                                         struct net_bridge_port *port,
1232                                         struct bridge_mcast_other_query *query,
1233                                         struct br_ip *saddr,
1234                                         unsigned long max_delay)
1235 {
1236         if (!br_multicast_select_querier(br, port, saddr))
1237                 return;
1238
1239         br_multicast_update_query_timer(br, query, max_delay);
1240         br_multicast_mark_router(br, port);
1241 }
1242
1243 static int br_ip4_multicast_query(struct net_bridge *br,
1244                                   struct net_bridge_port *port,
1245                                   struct sk_buff *skb,
1246                                   u16 vid)
1247 {
1248         const struct iphdr *iph = ip_hdr(skb);
1249         struct igmphdr *ih = igmp_hdr(skb);
1250         struct net_bridge_mdb_entry *mp;
1251         struct igmpv3_query *ih3;
1252         struct net_bridge_port_group *p;
1253         struct net_bridge_port_group __rcu **pp;
1254         struct br_ip saddr;
1255         unsigned long max_delay;
1256         unsigned long now = jiffies;
1257         __be32 group;
1258         int err = 0;
1259
1260         spin_lock(&br->multicast_lock);
1261         if (!netif_running(br->dev) ||
1262             (port && port->state == BR_STATE_DISABLED))
1263                 goto out;
1264
1265         group = ih->group;
1266
1267         if (skb->len == sizeof(*ih)) {
1268                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1269
1270                 if (!max_delay) {
1271                         max_delay = 10 * HZ;
1272                         group = 0;
1273                 }
1274         } else if (skb->len >= sizeof(*ih3)) {
1275                 ih3 = igmpv3_query_hdr(skb);
1276                 if (ih3->nsrcs)
1277                         goto out;
1278
1279                 max_delay = ih3->code ?
1280                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1281         } else {
1282                 goto out;
1283         }
1284
1285         if (!group) {
1286                 saddr.proto = htons(ETH_P_IP);
1287                 saddr.u.ip4 = iph->saddr;
1288
1289                 br_multicast_query_received(br, port, &br->ip4_other_query,
1290                                             &saddr, max_delay);
1291                 goto out;
1292         }
1293
1294         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1295         if (!mp)
1296                 goto out;
1297
1298         max_delay *= br->multicast_last_member_count;
1299
1300         if (mp->mglist &&
1301             (timer_pending(&mp->timer) ?
1302              time_after(mp->timer.expires, now + max_delay) :
1303              try_to_del_timer_sync(&mp->timer) >= 0))
1304                 mod_timer(&mp->timer, now + max_delay);
1305
1306         for (pp = &mp->ports;
1307              (p = mlock_dereference(*pp, br)) != NULL;
1308              pp = &p->next) {
1309                 if (timer_pending(&p->timer) ?
1310                     time_after(p->timer.expires, now + max_delay) :
1311                     try_to_del_timer_sync(&p->timer) >= 0)
1312                         mod_timer(&p->timer, now + max_delay);
1313         }
1314
1315 out:
1316         spin_unlock(&br->multicast_lock);
1317         return err;
1318 }
1319
1320 #if IS_ENABLED(CONFIG_IPV6)
1321 static int br_ip6_multicast_query(struct net_bridge *br,
1322                                   struct net_bridge_port *port,
1323                                   struct sk_buff *skb,
1324                                   u16 vid)
1325 {
1326         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1327         struct mld_msg *mld;
1328         struct net_bridge_mdb_entry *mp;
1329         struct mld2_query *mld2q;
1330         struct net_bridge_port_group *p;
1331         struct net_bridge_port_group __rcu **pp;
1332         struct br_ip saddr;
1333         unsigned long max_delay;
1334         unsigned long now = jiffies;
1335         const struct in6_addr *group = NULL;
1336         bool is_general_query;
1337         int err = 0;
1338
1339         spin_lock(&br->multicast_lock);
1340         if (!netif_running(br->dev) ||
1341             (port && port->state == BR_STATE_DISABLED))
1342                 goto out;
1343
1344         if (skb->len == sizeof(*mld)) {
1345                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1346                         err = -EINVAL;
1347                         goto out;
1348                 }
1349                 mld = (struct mld_msg *) icmp6_hdr(skb);
1350                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1351                 if (max_delay)
1352                         group = &mld->mld_mca;
1353         } else {
1354                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1355                         err = -EINVAL;
1356                         goto out;
1357                 }
1358                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1359                 if (!mld2q->mld2q_nsrcs)
1360                         group = &mld2q->mld2q_mca;
1361
1362                 max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1363         }
1364
1365         is_general_query = group && ipv6_addr_any(group);
1366
1367         if (is_general_query) {
1368                 saddr.proto = htons(ETH_P_IPV6);
1369                 saddr.u.ip6 = ip6h->saddr;
1370
1371                 br_multicast_query_received(br, port, &br->ip6_other_query,
1372                                             &saddr, max_delay);
1373                 goto out;
1374         } else if (!group) {
1375                 goto out;
1376         }
1377
1378         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1379         if (!mp)
1380                 goto out;
1381
1382         max_delay *= br->multicast_last_member_count;
1383         if (mp->mglist &&
1384             (timer_pending(&mp->timer) ?
1385              time_after(mp->timer.expires, now + max_delay) :
1386              try_to_del_timer_sync(&mp->timer) >= 0))
1387                 mod_timer(&mp->timer, now + max_delay);
1388
1389         for (pp = &mp->ports;
1390              (p = mlock_dereference(*pp, br)) != NULL;
1391              pp = &p->next) {
1392                 if (timer_pending(&p->timer) ?
1393                     time_after(p->timer.expires, now + max_delay) :
1394                     try_to_del_timer_sync(&p->timer) >= 0)
1395                         mod_timer(&p->timer, now + max_delay);
1396         }
1397
1398 out:
1399         spin_unlock(&br->multicast_lock);
1400         return err;
1401 }
1402 #endif
1403
1404 static void
1405 br_multicast_leave_group(struct net_bridge *br,
1406                          struct net_bridge_port *port,
1407                          struct br_ip *group,
1408                          struct bridge_mcast_other_query *other_query,
1409                          struct bridge_mcast_own_query *own_query)
1410 {
1411         struct net_bridge_mdb_htable *mdb;
1412         struct net_bridge_mdb_entry *mp;
1413         struct net_bridge_port_group *p;
1414         unsigned long now;
1415         unsigned long time;
1416
1417         spin_lock(&br->multicast_lock);
1418         if (!netif_running(br->dev) ||
1419             (port && port->state == BR_STATE_DISABLED) ||
1420             timer_pending(&other_query->timer))
1421                 goto out;
1422
1423         mdb = mlock_dereference(br->mdb, br);
1424         mp = br_mdb_ip_get(mdb, group);
1425         if (!mp)
1426                 goto out;
1427
1428         if (br->multicast_querier) {
1429                 __br_multicast_send_query(br, port, &mp->addr);
1430
1431                 time = jiffies + br->multicast_last_member_count *
1432                                  br->multicast_last_member_interval;
1433
1434                 mod_timer(&own_query->timer, time);
1435
1436                 for (p = mlock_dereference(mp->ports, br);
1437                      p != NULL;
1438                      p = mlock_dereference(p->next, br)) {
1439                         if (p->port != port)
1440                                 continue;
1441
1442                         if (!hlist_unhashed(&p->mglist) &&
1443                             (timer_pending(&p->timer) ?
1444                              time_after(p->timer.expires, time) :
1445                              try_to_del_timer_sync(&p->timer) >= 0)) {
1446                                 mod_timer(&p->timer, time);
1447                         }
1448
1449                         break;
1450                 }
1451         }
1452
1453         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1454                 struct net_bridge_port_group __rcu **pp;
1455
1456                 for (pp = &mp->ports;
1457                      (p = mlock_dereference(*pp, br)) != NULL;
1458                      pp = &p->next) {
1459                         if (p->port != port)
1460                                 continue;
1461
1462                         rcu_assign_pointer(*pp, p->next);
1463                         hlist_del_init(&p->mglist);
1464                         del_timer(&p->timer);
1465                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1466                         br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1467
1468                         if (!mp->ports && !mp->mglist &&
1469                             netif_running(br->dev))
1470                                 mod_timer(&mp->timer, jiffies);
1471                 }
1472                 goto out;
1473         }
1474
1475         now = jiffies;
1476         time = now + br->multicast_last_member_count *
1477                      br->multicast_last_member_interval;
1478
1479         if (!port) {
1480                 if (mp->mglist &&
1481                     (timer_pending(&mp->timer) ?
1482                      time_after(mp->timer.expires, time) :
1483                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1484                         mod_timer(&mp->timer, time);
1485                 }
1486
1487                 goto out;
1488         }
1489
1490         for (p = mlock_dereference(mp->ports, br);
1491              p != NULL;
1492              p = mlock_dereference(p->next, br)) {
1493                 if (p->port != port)
1494                         continue;
1495
1496                 if (!hlist_unhashed(&p->mglist) &&
1497                     (timer_pending(&p->timer) ?
1498                      time_after(p->timer.expires, time) :
1499                      try_to_del_timer_sync(&p->timer) >= 0)) {
1500                         mod_timer(&p->timer, time);
1501                 }
1502
1503                 break;
1504         }
1505 out:
1506         spin_unlock(&br->multicast_lock);
1507 }
1508
1509 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1510                                          struct net_bridge_port *port,
1511                                          __be32 group,
1512                                          __u16 vid)
1513 {
1514         struct br_ip br_group;
1515         struct bridge_mcast_own_query *own_query;
1516
1517         if (ipv4_is_local_multicast(group))
1518                 return;
1519
1520         own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1521
1522         br_group.u.ip4 = group;
1523         br_group.proto = htons(ETH_P_IP);
1524         br_group.vid = vid;
1525
1526         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1527                                  own_query);
1528 }
1529
1530 #if IS_ENABLED(CONFIG_IPV6)
1531 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1532                                          struct net_bridge_port *port,
1533                                          const struct in6_addr *group,
1534                                          __u16 vid)
1535 {
1536         struct br_ip br_group;
1537         struct bridge_mcast_own_query *own_query;
1538
1539         if (ipv6_addr_is_ll_all_nodes(group))
1540                 return;
1541
1542         own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1543
1544         br_group.u.ip6 = *group;
1545         br_group.proto = htons(ETH_P_IPV6);
1546         br_group.vid = vid;
1547
1548         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1549                                  own_query);
1550 }
1551 #endif
1552
1553 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1554                                  struct net_bridge_port *port,
1555                                  struct sk_buff *skb,
1556                                  u16 vid)
1557 {
1558         struct sk_buff *skb_trimmed = NULL;
1559         struct igmphdr *ih;
1560         int err;
1561
1562         err = ip_mc_check_igmp(skb, &skb_trimmed);
1563
1564         if (err == -ENOMSG) {
1565                 if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr))
1566                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1567                 return 0;
1568         } else if (err < 0) {
1569                 return err;
1570         }
1571
1572         BR_INPUT_SKB_CB(skb)->igmp = 1;
1573         ih = igmp_hdr(skb);
1574
1575         switch (ih->type) {
1576         case IGMP_HOST_MEMBERSHIP_REPORT:
1577         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1578                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1579                 err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1580                 break;
1581         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1582                 err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
1583                 break;
1584         case IGMP_HOST_MEMBERSHIP_QUERY:
1585                 err = br_ip4_multicast_query(br, port, skb_trimmed, vid);
1586                 break;
1587         case IGMP_HOST_LEAVE_MESSAGE:
1588                 br_ip4_multicast_leave_group(br, port, ih->group, vid);
1589                 break;
1590         }
1591
1592         if (skb_trimmed)
1593                 kfree_skb(skb_trimmed);
1594
1595         return err;
1596 }
1597
1598 #if IS_ENABLED(CONFIG_IPV6)
1599 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1600                                  struct net_bridge_port *port,
1601                                  struct sk_buff *skb,
1602                                  u16 vid)
1603 {
1604         struct sk_buff *skb_trimmed = NULL;
1605         struct mld_msg *mld;
1606         int err;
1607
1608         err = ipv6_mc_check_mld(skb, &skb_trimmed);
1609
1610         if (err == -ENOMSG) {
1611                 if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
1612                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1613                 return 0;
1614         } else if (err < 0) {
1615                 return err;
1616         }
1617
1618         BR_INPUT_SKB_CB(skb)->igmp = 1;
1619         mld = (struct mld_msg *)skb_transport_header(skb);
1620
1621         switch (mld->mld_type) {
1622         case ICMPV6_MGM_REPORT:
1623                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1624                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1625                 break;
1626         case ICMPV6_MLD2_REPORT:
1627                 err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
1628                 break;
1629         case ICMPV6_MGM_QUERY:
1630                 err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
1631                 break;
1632         case ICMPV6_MGM_REDUCTION:
1633                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1634                 break;
1635         }
1636
1637         if (skb_trimmed)
1638                 kfree_skb(skb_trimmed);
1639
1640         return err;
1641 }
1642 #endif
1643
1644 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1645                      struct sk_buff *skb, u16 vid)
1646 {
1647         BR_INPUT_SKB_CB(skb)->igmp = 0;
1648         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1649
1650         if (br->multicast_disabled)
1651                 return 0;
1652
1653         switch (skb->protocol) {
1654         case htons(ETH_P_IP):
1655                 return br_multicast_ipv4_rcv(br, port, skb, vid);
1656 #if IS_ENABLED(CONFIG_IPV6)
1657         case htons(ETH_P_IPV6):
1658                 return br_multicast_ipv6_rcv(br, port, skb, vid);
1659 #endif
1660         }
1661
1662         return 0;
1663 }
1664
1665 static void br_multicast_query_expired(struct net_bridge *br,
1666                                        struct bridge_mcast_own_query *query,
1667                                        struct bridge_mcast_querier *querier)
1668 {
1669         spin_lock(&br->multicast_lock);
1670         if (query->startup_sent < br->multicast_startup_query_count)
1671                 query->startup_sent++;
1672
1673         RCU_INIT_POINTER(querier->port, NULL);
1674         br_multicast_send_query(br, NULL, query);
1675         spin_unlock(&br->multicast_lock);
1676 }
1677
1678 static void br_ip4_multicast_query_expired(unsigned long data)
1679 {
1680         struct net_bridge *br = (void *)data;
1681
1682         br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1683 }
1684
1685 #if IS_ENABLED(CONFIG_IPV6)
1686 static void br_ip6_multicast_query_expired(unsigned long data)
1687 {
1688         struct net_bridge *br = (void *)data;
1689
1690         br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1691 }
1692 #endif
1693
1694 void br_multicast_init(struct net_bridge *br)
1695 {
1696         br->hash_elasticity = 4;
1697         br->hash_max = 512;
1698
1699         br->multicast_router = 1;
1700         br->multicast_querier = 0;
1701         br->multicast_query_use_ifaddr = 0;
1702         br->multicast_last_member_count = 2;
1703         br->multicast_startup_query_count = 2;
1704
1705         br->multicast_last_member_interval = HZ;
1706         br->multicast_query_response_interval = 10 * HZ;
1707         br->multicast_startup_query_interval = 125 * HZ / 4;
1708         br->multicast_query_interval = 125 * HZ;
1709         br->multicast_querier_interval = 255 * HZ;
1710         br->multicast_membership_interval = 260 * HZ;
1711
1712         br->ip4_other_query.delay_time = 0;
1713         br->ip4_querier.port = NULL;
1714 #if IS_ENABLED(CONFIG_IPV6)
1715         br->ip6_other_query.delay_time = 0;
1716         br->ip6_querier.port = NULL;
1717 #endif
1718
1719         spin_lock_init(&br->multicast_lock);
1720         setup_timer(&br->multicast_router_timer,
1721                     br_multicast_local_router_expired, 0);
1722         setup_timer(&br->ip4_other_query.timer,
1723                     br_ip4_multicast_querier_expired, (unsigned long)br);
1724         setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1725                     (unsigned long)br);
1726 #if IS_ENABLED(CONFIG_IPV6)
1727         setup_timer(&br->ip6_other_query.timer,
1728                     br_ip6_multicast_querier_expired, (unsigned long)br);
1729         setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1730                     (unsigned long)br);
1731 #endif
1732 }
1733
1734 static void __br_multicast_open(struct net_bridge *br,
1735                                 struct bridge_mcast_own_query *query)
1736 {
1737         query->startup_sent = 0;
1738
1739         if (br->multicast_disabled)
1740                 return;
1741
1742         mod_timer(&query->timer, jiffies);
1743 }
1744
1745 void br_multicast_open(struct net_bridge *br)
1746 {
1747         __br_multicast_open(br, &br->ip4_own_query);
1748 #if IS_ENABLED(CONFIG_IPV6)
1749         __br_multicast_open(br, &br->ip6_own_query);
1750 #endif
1751 }
1752
1753 void br_multicast_stop(struct net_bridge *br)
1754 {
1755         struct net_bridge_mdb_htable *mdb;
1756         struct net_bridge_mdb_entry *mp;
1757         struct hlist_node *n;
1758         u32 ver;
1759         int i;
1760
1761         del_timer_sync(&br->multicast_router_timer);
1762         del_timer_sync(&br->ip4_other_query.timer);
1763         del_timer_sync(&br->ip4_own_query.timer);
1764 #if IS_ENABLED(CONFIG_IPV6)
1765         del_timer_sync(&br->ip6_other_query.timer);
1766         del_timer_sync(&br->ip6_own_query.timer);
1767 #endif
1768
1769         spin_lock_bh(&br->multicast_lock);
1770         mdb = mlock_dereference(br->mdb, br);
1771         if (!mdb)
1772                 goto out;
1773
1774         br->mdb = NULL;
1775
1776         ver = mdb->ver;
1777         for (i = 0; i < mdb->max; i++) {
1778                 hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1779                                           hlist[ver]) {
1780                         del_timer(&mp->timer);
1781                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1782                 }
1783         }
1784
1785         if (mdb->old) {
1786                 spin_unlock_bh(&br->multicast_lock);
1787                 rcu_barrier_bh();
1788                 spin_lock_bh(&br->multicast_lock);
1789                 WARN_ON(mdb->old);
1790         }
1791
1792         mdb->old = mdb;
1793         call_rcu_bh(&mdb->rcu, br_mdb_free);
1794
1795 out:
1796         spin_unlock_bh(&br->multicast_lock);
1797 }
1798
1799 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1800 {
1801         int err = -EINVAL;
1802
1803         spin_lock_bh(&br->multicast_lock);
1804
1805         switch (val) {
1806         case 0:
1807         case 2:
1808                 del_timer(&br->multicast_router_timer);
1809                 /* fall through */
1810         case 1:
1811                 br->multicast_router = val;
1812                 err = 0;
1813                 break;
1814         }
1815
1816         spin_unlock_bh(&br->multicast_lock);
1817
1818         return err;
1819 }
1820
1821 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1822 {
1823         struct net_bridge *br = p->br;
1824         int err = -EINVAL;
1825
1826         spin_lock(&br->multicast_lock);
1827
1828         switch (val) {
1829         case 0:
1830         case 1:
1831         case 2:
1832                 p->multicast_router = val;
1833                 err = 0;
1834
1835                 if (val < 2 && !hlist_unhashed(&p->rlist))
1836                         hlist_del_init_rcu(&p->rlist);
1837
1838                 if (val == 1)
1839                         break;
1840
1841                 del_timer(&p->multicast_router_timer);
1842
1843                 if (val == 0)
1844                         break;
1845
1846                 br_multicast_add_router(br, p);
1847                 break;
1848         }
1849
1850         spin_unlock(&br->multicast_lock);
1851
1852         return err;
1853 }
1854
1855 static void br_multicast_start_querier(struct net_bridge *br,
1856                                        struct bridge_mcast_own_query *query)
1857 {
1858         struct net_bridge_port *port;
1859
1860         __br_multicast_open(br, query);
1861
1862         list_for_each_entry(port, &br->port_list, list) {
1863                 if (port->state == BR_STATE_DISABLED ||
1864                     port->state == BR_STATE_BLOCKING)
1865                         continue;
1866
1867                 if (query == &br->ip4_own_query)
1868                         br_multicast_enable(&port->ip4_own_query);
1869 #if IS_ENABLED(CONFIG_IPV6)
1870                 else
1871                         br_multicast_enable(&port->ip6_own_query);
1872 #endif
1873         }
1874 }
1875
1876 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1877 {
1878         int err = 0;
1879         struct net_bridge_mdb_htable *mdb;
1880
1881         spin_lock_bh(&br->multicast_lock);
1882         if (br->multicast_disabled == !val)
1883                 goto unlock;
1884
1885         br->multicast_disabled = !val;
1886         if (br->multicast_disabled)
1887                 goto unlock;
1888
1889         if (!netif_running(br->dev))
1890                 goto unlock;
1891
1892         mdb = mlock_dereference(br->mdb, br);
1893         if (mdb) {
1894                 if (mdb->old) {
1895                         err = -EEXIST;
1896 rollback:
1897                         br->multicast_disabled = !!val;
1898                         goto unlock;
1899                 }
1900
1901                 err = br_mdb_rehash(&br->mdb, mdb->max,
1902                                     br->hash_elasticity);
1903                 if (err)
1904                         goto rollback;
1905         }
1906
1907         br_multicast_start_querier(br, &br->ip4_own_query);
1908 #if IS_ENABLED(CONFIG_IPV6)
1909         br_multicast_start_querier(br, &br->ip6_own_query);
1910 #endif
1911
1912 unlock:
1913         spin_unlock_bh(&br->multicast_lock);
1914
1915         return err;
1916 }
1917
1918 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1919 {
1920         unsigned long max_delay;
1921
1922         val = !!val;
1923
1924         spin_lock_bh(&br->multicast_lock);
1925         if (br->multicast_querier == val)
1926                 goto unlock;
1927
1928         br->multicast_querier = val;
1929         if (!val)
1930                 goto unlock;
1931
1932         max_delay = br->multicast_query_response_interval;
1933
1934         if (!timer_pending(&br->ip4_other_query.timer))
1935                 br->ip4_other_query.delay_time = jiffies + max_delay;
1936
1937         br_multicast_start_querier(br, &br->ip4_own_query);
1938
1939 #if IS_ENABLED(CONFIG_IPV6)
1940         if (!timer_pending(&br->ip6_other_query.timer))
1941                 br->ip6_other_query.delay_time = jiffies + max_delay;
1942
1943         br_multicast_start_querier(br, &br->ip6_own_query);
1944 #endif
1945
1946 unlock:
1947         spin_unlock_bh(&br->multicast_lock);
1948
1949         return 0;
1950 }
1951
1952 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1953 {
1954         int err = -EINVAL;
1955         u32 old;
1956         struct net_bridge_mdb_htable *mdb;
1957
1958         spin_lock_bh(&br->multicast_lock);
1959         if (!is_power_of_2(val))
1960                 goto unlock;
1961
1962         mdb = mlock_dereference(br->mdb, br);
1963         if (mdb && val < mdb->size)
1964                 goto unlock;
1965
1966         err = 0;
1967
1968         old = br->hash_max;
1969         br->hash_max = val;
1970
1971         if (mdb) {
1972                 if (mdb->old) {
1973                         err = -EEXIST;
1974 rollback:
1975                         br->hash_max = old;
1976                         goto unlock;
1977                 }
1978
1979                 err = br_mdb_rehash(&br->mdb, br->hash_max,
1980                                     br->hash_elasticity);
1981                 if (err)
1982                         goto rollback;
1983         }
1984
1985 unlock:
1986         spin_unlock_bh(&br->multicast_lock);
1987
1988         return err;
1989 }
1990
1991 /**
1992  * br_multicast_list_adjacent - Returns snooped multicast addresses
1993  * @dev:        The bridge port adjacent to which to retrieve addresses
1994  * @br_ip_list: The list to store found, snooped multicast IP addresses in
1995  *
1996  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
1997  * snooping feature on all bridge ports of dev's bridge device, excluding
1998  * the addresses from dev itself.
1999  *
2000  * Returns the number of items added to br_ip_list.
2001  *
2002  * Notes:
2003  * - br_ip_list needs to be initialized by caller
2004  * - br_ip_list might contain duplicates in the end
2005  *   (needs to be taken care of by caller)
2006  * - br_ip_list needs to be freed by caller
2007  */
2008 int br_multicast_list_adjacent(struct net_device *dev,
2009                                struct list_head *br_ip_list)
2010 {
2011         struct net_bridge *br;
2012         struct net_bridge_port *port;
2013         struct net_bridge_port_group *group;
2014         struct br_ip_list *entry;
2015         int count = 0;
2016
2017         rcu_read_lock();
2018         if (!br_ip_list || !br_port_exists(dev))
2019                 goto unlock;
2020
2021         port = br_port_get_rcu(dev);
2022         if (!port || !port->br)
2023                 goto unlock;
2024
2025         br = port->br;
2026
2027         list_for_each_entry_rcu(port, &br->port_list, list) {
2028                 if (!port->dev || port->dev == dev)
2029                         continue;
2030
2031                 hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2032                         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2033                         if (!entry)
2034                                 goto unlock;
2035
2036                         entry->addr = group->addr;
2037                         list_add(&entry->list, br_ip_list);
2038                         count++;
2039                 }
2040         }
2041
2042 unlock:
2043         rcu_read_unlock();
2044         return count;
2045 }
2046 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2047
2048 /**
2049  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2050  * @dev: The bridge port providing the bridge on which to check for a querier
2051  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2052  *
2053  * Checks whether the given interface has a bridge on top and if so returns
2054  * true if a valid querier exists anywhere on the bridged link layer.
2055  * Otherwise returns false.
2056  */
2057 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2058 {
2059         struct net_bridge *br;
2060         struct net_bridge_port *port;
2061         struct ethhdr eth;
2062         bool ret = false;
2063
2064         rcu_read_lock();
2065         if (!br_port_exists(dev))
2066                 goto unlock;
2067
2068         port = br_port_get_rcu(dev);
2069         if (!port || !port->br)
2070                 goto unlock;
2071
2072         br = port->br;
2073
2074         memset(&eth, 0, sizeof(eth));
2075         eth.h_proto = htons(proto);
2076
2077         ret = br_multicast_querier_exists(br, &eth);
2078
2079 unlock:
2080         rcu_read_unlock();
2081         return ret;
2082 }
2083 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2084
2085 /**
2086  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2087  * @dev: The bridge port adjacent to which to check for a querier
2088  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2089  *
2090  * Checks whether the given interface has a bridge on top and if so returns
2091  * true if a selected querier is behind one of the other ports of this
2092  * bridge. Otherwise returns false.
2093  */
2094 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2095 {
2096         struct net_bridge *br;
2097         struct net_bridge_port *port;
2098         bool ret = false;
2099
2100         rcu_read_lock();
2101         if (!br_port_exists(dev))
2102                 goto unlock;
2103
2104         port = br_port_get_rcu(dev);
2105         if (!port || !port->br)
2106                 goto unlock;
2107
2108         br = port->br;
2109
2110         switch (proto) {
2111         case ETH_P_IP:
2112                 if (!timer_pending(&br->ip4_other_query.timer) ||
2113                     rcu_dereference(br->ip4_querier.port) == port)
2114                         goto unlock;
2115                 break;
2116 #if IS_ENABLED(CONFIG_IPV6)
2117         case ETH_P_IPV6:
2118                 if (!timer_pending(&br->ip6_other_query.timer) ||
2119                     rcu_dereference(br->ip6_querier.port) == port)
2120                         goto unlock;
2121                 break;
2122 #endif
2123         default:
2124                 goto unlock;
2125         }
2126
2127         ret = true;
2128 unlock:
2129         rcu_read_unlock();
2130         return ret;
2131 }
2132 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);