thermal: rockchip: optimize sensor auto accessing period
[firefly-linux-kernel-4.4.55.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                 br_mdb_notify(br->dev, p->port, &pg->addr, RTM_DELMDB,
287                               p->state);
288                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
289
290                 if (!mp->ports && !mp->mglist &&
291                     netif_running(br->dev))
292                         mod_timer(&mp->timer, jiffies);
293
294                 return;
295         }
296
297         WARN_ON(1);
298 }
299
300 static void br_multicast_port_group_expired(unsigned long data)
301 {
302         struct net_bridge_port_group *pg = (void *)data;
303         struct net_bridge *br = pg->port->br;
304
305         spin_lock(&br->multicast_lock);
306         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
307             hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
308                 goto out;
309
310         br_multicast_del_pg(br, pg);
311
312 out:
313         spin_unlock(&br->multicast_lock);
314 }
315
316 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
317                          int elasticity)
318 {
319         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
320         struct net_bridge_mdb_htable *mdb;
321         int err;
322
323         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
324         if (!mdb)
325                 return -ENOMEM;
326
327         mdb->max = max;
328         mdb->old = old;
329
330         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
331         if (!mdb->mhash) {
332                 kfree(mdb);
333                 return -ENOMEM;
334         }
335
336         mdb->size = old ? old->size : 0;
337         mdb->ver = old ? old->ver ^ 1 : 0;
338
339         if (!old || elasticity)
340                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
341         else
342                 mdb->secret = old->secret;
343
344         if (!old)
345                 goto out;
346
347         err = br_mdb_copy(mdb, old, elasticity);
348         if (err) {
349                 kfree(mdb->mhash);
350                 kfree(mdb);
351                 return err;
352         }
353
354         br_mdb_rehash_seq++;
355         call_rcu_bh(&mdb->rcu, br_mdb_free);
356
357 out:
358         rcu_assign_pointer(*mdbp, mdb);
359
360         return 0;
361 }
362
363 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
364                                                     __be32 group)
365 {
366         struct sk_buff *skb;
367         struct igmphdr *ih;
368         struct ethhdr *eth;
369         struct iphdr *iph;
370
371         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
372                                                  sizeof(*ih) + 4);
373         if (!skb)
374                 goto out;
375
376         skb->protocol = htons(ETH_P_IP);
377
378         skb_reset_mac_header(skb);
379         eth = eth_hdr(skb);
380
381         ether_addr_copy(eth->h_source, br->dev->dev_addr);
382         eth->h_dest[0] = 1;
383         eth->h_dest[1] = 0;
384         eth->h_dest[2] = 0x5e;
385         eth->h_dest[3] = 0;
386         eth->h_dest[4] = 0;
387         eth->h_dest[5] = 1;
388         eth->h_proto = htons(ETH_P_IP);
389         skb_put(skb, sizeof(*eth));
390
391         skb_set_network_header(skb, skb->len);
392         iph = ip_hdr(skb);
393
394         iph->version = 4;
395         iph->ihl = 6;
396         iph->tos = 0xc0;
397         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
398         iph->id = 0;
399         iph->frag_off = htons(IP_DF);
400         iph->ttl = 1;
401         iph->protocol = IPPROTO_IGMP;
402         iph->saddr = br->multicast_query_use_ifaddr ?
403                      inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
404         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
405         ((u8 *)&iph[1])[0] = IPOPT_RA;
406         ((u8 *)&iph[1])[1] = 4;
407         ((u8 *)&iph[1])[2] = 0;
408         ((u8 *)&iph[1])[3] = 0;
409         ip_send_check(iph);
410         skb_put(skb, 24);
411
412         skb_set_transport_header(skb, skb->len);
413         ih = igmp_hdr(skb);
414         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
415         ih->code = (group ? br->multicast_last_member_interval :
416                             br->multicast_query_response_interval) /
417                    (HZ / IGMP_TIMER_SCALE);
418         ih->group = group;
419         ih->csum = 0;
420         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
421         skb_put(skb, sizeof(*ih));
422
423         __skb_pull(skb, sizeof(*eth));
424
425 out:
426         return skb;
427 }
428
429 #if IS_ENABLED(CONFIG_IPV6)
430 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
431                                                     const struct in6_addr *group)
432 {
433         struct sk_buff *skb;
434         struct ipv6hdr *ip6h;
435         struct mld_msg *mldq;
436         struct ethhdr *eth;
437         u8 *hopopt;
438         unsigned long interval;
439
440         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
441                                                  8 + sizeof(*mldq));
442         if (!skb)
443                 goto out;
444
445         skb->protocol = htons(ETH_P_IPV6);
446
447         /* Ethernet header */
448         skb_reset_mac_header(skb);
449         eth = eth_hdr(skb);
450
451         ether_addr_copy(eth->h_source, br->dev->dev_addr);
452         eth->h_proto = htons(ETH_P_IPV6);
453         skb_put(skb, sizeof(*eth));
454
455         /* IPv6 header + HbH option */
456         skb_set_network_header(skb, skb->len);
457         ip6h = ipv6_hdr(skb);
458
459         *(__force __be32 *)ip6h = htonl(0x60000000);
460         ip6h->payload_len = htons(8 + sizeof(*mldq));
461         ip6h->nexthdr = IPPROTO_HOPOPTS;
462         ip6h->hop_limit = 1;
463         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
464         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
465                                &ip6h->saddr)) {
466                 kfree_skb(skb);
467                 return NULL;
468         }
469         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
470
471         hopopt = (u8 *)(ip6h + 1);
472         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
473         hopopt[1] = 0;                          /* length of HbH */
474         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
475         hopopt[3] = 2;                          /* Length of RA Option */
476         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
477         hopopt[5] = 0;
478         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
479         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
480
481         skb_put(skb, sizeof(*ip6h) + 8);
482
483         /* ICMPv6 */
484         skb_set_transport_header(skb, skb->len);
485         mldq = (struct mld_msg *) icmp6_hdr(skb);
486
487         interval = ipv6_addr_any(group) ?
488                         br->multicast_query_response_interval :
489                         br->multicast_last_member_interval;
490
491         mldq->mld_type = ICMPV6_MGM_QUERY;
492         mldq->mld_code = 0;
493         mldq->mld_cksum = 0;
494         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
495         mldq->mld_reserved = 0;
496         mldq->mld_mca = *group;
497
498         /* checksum */
499         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
500                                           sizeof(*mldq), IPPROTO_ICMPV6,
501                                           csum_partial(mldq,
502                                                        sizeof(*mldq), 0));
503         skb_put(skb, sizeof(*mldq));
504
505         __skb_pull(skb, sizeof(*eth));
506
507 out:
508         return skb;
509 }
510 #endif
511
512 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
513                                                 struct br_ip *addr)
514 {
515         switch (addr->proto) {
516         case htons(ETH_P_IP):
517                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
518 #if IS_ENABLED(CONFIG_IPV6)
519         case htons(ETH_P_IPV6):
520                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
521 #endif
522         }
523         return NULL;
524 }
525
526 static struct net_bridge_mdb_entry *br_multicast_get_group(
527         struct net_bridge *br, struct net_bridge_port *port,
528         struct br_ip *group, int hash)
529 {
530         struct net_bridge_mdb_htable *mdb;
531         struct net_bridge_mdb_entry *mp;
532         unsigned int count = 0;
533         unsigned int max;
534         int elasticity;
535         int err;
536
537         mdb = rcu_dereference_protected(br->mdb, 1);
538         hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
539                 count++;
540                 if (unlikely(br_ip_equal(group, &mp->addr)))
541                         return mp;
542         }
543
544         elasticity = 0;
545         max = mdb->max;
546
547         if (unlikely(count > br->hash_elasticity && count)) {
548                 if (net_ratelimit())
549                         br_info(br, "Multicast hash table "
550                                 "chain limit reached: %s\n",
551                                 port ? port->dev->name : br->dev->name);
552
553                 elasticity = br->hash_elasticity;
554         }
555
556         if (mdb->size >= max) {
557                 max *= 2;
558                 if (unlikely(max > br->hash_max)) {
559                         br_warn(br, "Multicast hash table maximum of %d "
560                                 "reached, disabling snooping: %s\n",
561                                 br->hash_max,
562                                 port ? port->dev->name : br->dev->name);
563                         err = -E2BIG;
564 disable:
565                         br->multicast_disabled = 1;
566                         goto err;
567                 }
568         }
569
570         if (max > mdb->max || elasticity) {
571                 if (mdb->old) {
572                         if (net_ratelimit())
573                                 br_info(br, "Multicast hash table "
574                                         "on fire: %s\n",
575                                         port ? port->dev->name : br->dev->name);
576                         err = -EEXIST;
577                         goto err;
578                 }
579
580                 err = br_mdb_rehash(&br->mdb, max, elasticity);
581                 if (err) {
582                         br_warn(br, "Cannot rehash multicast "
583                                 "hash table, disabling snooping: %s, %d, %d\n",
584                                 port ? port->dev->name : br->dev->name,
585                                 mdb->size, err);
586                         goto disable;
587                 }
588
589                 err = -EAGAIN;
590                 goto err;
591         }
592
593         return NULL;
594
595 err:
596         mp = ERR_PTR(err);
597         return mp;
598 }
599
600 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
601         struct net_bridge_port *port, struct br_ip *group)
602 {
603         struct net_bridge_mdb_htable *mdb;
604         struct net_bridge_mdb_entry *mp;
605         int hash;
606         int err;
607
608         mdb = rcu_dereference_protected(br->mdb, 1);
609         if (!mdb) {
610                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
611                 if (err)
612                         return ERR_PTR(err);
613                 goto rehash;
614         }
615
616         hash = br_ip_hash(mdb, group);
617         mp = br_multicast_get_group(br, port, group, hash);
618         switch (PTR_ERR(mp)) {
619         case 0:
620                 break;
621
622         case -EAGAIN:
623 rehash:
624                 mdb = rcu_dereference_protected(br->mdb, 1);
625                 hash = br_ip_hash(mdb, group);
626                 break;
627
628         default:
629                 goto out;
630         }
631
632         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
633         if (unlikely(!mp))
634                 return ERR_PTR(-ENOMEM);
635
636         mp->br = br;
637         mp->addr = *group;
638         setup_timer(&mp->timer, br_multicast_group_expired,
639                     (unsigned long)mp);
640
641         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
642         mdb->size++;
643
644 out:
645         return mp;
646 }
647
648 struct net_bridge_port_group *br_multicast_new_port_group(
649                         struct net_bridge_port *port,
650                         struct br_ip *group,
651                         struct net_bridge_port_group __rcu *next,
652                         unsigned char state)
653 {
654         struct net_bridge_port_group *p;
655
656         p = kzalloc(sizeof(*p), GFP_ATOMIC);
657         if (unlikely(!p))
658                 return NULL;
659
660         p->addr = *group;
661         p->port = port;
662         p->state = state;
663         rcu_assign_pointer(p->next, next);
664         hlist_add_head(&p->mglist, &port->mglist);
665         setup_timer(&p->timer, br_multicast_port_group_expired,
666                     (unsigned long)p);
667         return p;
668 }
669
670 static int br_multicast_add_group(struct net_bridge *br,
671                                   struct net_bridge_port *port,
672                                   struct br_ip *group)
673 {
674         struct net_bridge_mdb_entry *mp;
675         struct net_bridge_port_group *p;
676         struct net_bridge_port_group __rcu **pp;
677         unsigned long now = jiffies;
678         int err;
679
680         spin_lock(&br->multicast_lock);
681         if (!netif_running(br->dev) ||
682             (port && port->state == BR_STATE_DISABLED))
683                 goto out;
684
685         mp = br_multicast_new_group(br, port, group);
686         err = PTR_ERR(mp);
687         if (IS_ERR(mp))
688                 goto err;
689
690         if (!port) {
691                 mp->mglist = true;
692                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
693                 goto out;
694         }
695
696         for (pp = &mp->ports;
697              (p = mlock_dereference(*pp, br)) != NULL;
698              pp = &p->next) {
699                 if (p->port == port)
700                         goto found;
701                 if ((unsigned long)p->port < (unsigned long)port)
702                         break;
703         }
704
705         p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
706         if (unlikely(!p))
707                 goto err;
708         rcu_assign_pointer(*pp, p);
709         br_mdb_notify(br->dev, port, group, RTM_NEWMDB, MDB_TEMPORARY);
710
711 found:
712         mod_timer(&p->timer, now + br->multicast_membership_interval);
713 out:
714         err = 0;
715
716 err:
717         spin_unlock(&br->multicast_lock);
718         return err;
719 }
720
721 static int br_ip4_multicast_add_group(struct net_bridge *br,
722                                       struct net_bridge_port *port,
723                                       __be32 group,
724                                       __u16 vid)
725 {
726         struct br_ip br_group;
727
728         if (ipv4_is_local_multicast(group))
729                 return 0;
730
731         br_group.u.ip4 = group;
732         br_group.proto = htons(ETH_P_IP);
733         br_group.vid = vid;
734
735         return br_multicast_add_group(br, port, &br_group);
736 }
737
738 #if IS_ENABLED(CONFIG_IPV6)
739 static int br_ip6_multicast_add_group(struct net_bridge *br,
740                                       struct net_bridge_port *port,
741                                       const struct in6_addr *group,
742                                       __u16 vid)
743 {
744         struct br_ip br_group;
745
746         if (ipv6_addr_is_ll_all_nodes(group))
747                 return 0;
748
749         br_group.u.ip6 = *group;
750         br_group.proto = htons(ETH_P_IPV6);
751         br_group.vid = vid;
752
753         return br_multicast_add_group(br, port, &br_group);
754 }
755 #endif
756
757 static void br_multicast_router_expired(unsigned long data)
758 {
759         struct net_bridge_port *port = (void *)data;
760         struct net_bridge *br = port->br;
761
762         spin_lock(&br->multicast_lock);
763         if (port->multicast_router != 1 ||
764             timer_pending(&port->multicast_router_timer) ||
765             hlist_unhashed(&port->rlist))
766                 goto out;
767
768         hlist_del_init_rcu(&port->rlist);
769         br_rtr_notify(br->dev, port, RTM_DELMDB);
770
771 out:
772         spin_unlock(&br->multicast_lock);
773 }
774
775 static void br_multicast_local_router_expired(unsigned long data)
776 {
777 }
778
779 static void br_multicast_querier_expired(struct net_bridge *br,
780                                          struct bridge_mcast_own_query *query)
781 {
782         spin_lock(&br->multicast_lock);
783         if (!netif_running(br->dev) || br->multicast_disabled)
784                 goto out;
785
786         br_multicast_start_querier(br, query);
787
788 out:
789         spin_unlock(&br->multicast_lock);
790 }
791
792 static void br_ip4_multicast_querier_expired(unsigned long data)
793 {
794         struct net_bridge *br = (void *)data;
795
796         br_multicast_querier_expired(br, &br->ip4_own_query);
797 }
798
799 #if IS_ENABLED(CONFIG_IPV6)
800 static void br_ip6_multicast_querier_expired(unsigned long data)
801 {
802         struct net_bridge *br = (void *)data;
803
804         br_multicast_querier_expired(br, &br->ip6_own_query);
805 }
806 #endif
807
808 static void br_multicast_select_own_querier(struct net_bridge *br,
809                                             struct br_ip *ip,
810                                             struct sk_buff *skb)
811 {
812         if (ip->proto == htons(ETH_P_IP))
813                 br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
814 #if IS_ENABLED(CONFIG_IPV6)
815         else
816                 br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
817 #endif
818 }
819
820 static void __br_multicast_send_query(struct net_bridge *br,
821                                       struct net_bridge_port *port,
822                                       struct br_ip *ip)
823 {
824         struct sk_buff *skb;
825
826         skb = br_multicast_alloc_query(br, ip);
827         if (!skb)
828                 return;
829
830         if (port) {
831                 skb->dev = port->dev;
832                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
833                         dev_net(port->dev), NULL, skb, NULL, skb->dev,
834                         br_dev_queue_push_xmit);
835         } else {
836                 br_multicast_select_own_querier(br, ip, skb);
837                 netif_rx(skb);
838         }
839 }
840
841 static void br_multicast_send_query(struct net_bridge *br,
842                                     struct net_bridge_port *port,
843                                     struct bridge_mcast_own_query *own_query)
844 {
845         unsigned long time;
846         struct br_ip br_group;
847         struct bridge_mcast_other_query *other_query = NULL;
848
849         if (!netif_running(br->dev) || br->multicast_disabled ||
850             !br->multicast_querier)
851                 return;
852
853         memset(&br_group.u, 0, sizeof(br_group.u));
854
855         if (port ? (own_query == &port->ip4_own_query) :
856                    (own_query == &br->ip4_own_query)) {
857                 other_query = &br->ip4_other_query;
858                 br_group.proto = htons(ETH_P_IP);
859 #if IS_ENABLED(CONFIG_IPV6)
860         } else {
861                 other_query = &br->ip6_other_query;
862                 br_group.proto = htons(ETH_P_IPV6);
863 #endif
864         }
865
866         if (!other_query || timer_pending(&other_query->timer))
867                 return;
868
869         __br_multicast_send_query(br, port, &br_group);
870
871         time = jiffies;
872         time += own_query->startup_sent < br->multicast_startup_query_count ?
873                 br->multicast_startup_query_interval :
874                 br->multicast_query_interval;
875         mod_timer(&own_query->timer, time);
876 }
877
878 static void
879 br_multicast_port_query_expired(struct net_bridge_port *port,
880                                 struct bridge_mcast_own_query *query)
881 {
882         struct net_bridge *br = port->br;
883
884         spin_lock(&br->multicast_lock);
885         if (port->state == BR_STATE_DISABLED ||
886             port->state == BR_STATE_BLOCKING)
887                 goto out;
888
889         if (query->startup_sent < br->multicast_startup_query_count)
890                 query->startup_sent++;
891
892         br_multicast_send_query(port->br, port, query);
893
894 out:
895         spin_unlock(&br->multicast_lock);
896 }
897
898 static void br_ip4_multicast_port_query_expired(unsigned long data)
899 {
900         struct net_bridge_port *port = (void *)data;
901
902         br_multicast_port_query_expired(port, &port->ip4_own_query);
903 }
904
905 #if IS_ENABLED(CONFIG_IPV6)
906 static void br_ip6_multicast_port_query_expired(unsigned long data)
907 {
908         struct net_bridge_port *port = (void *)data;
909
910         br_multicast_port_query_expired(port, &port->ip6_own_query);
911 }
912 #endif
913
914 void br_multicast_add_port(struct net_bridge_port *port)
915 {
916         port->multicast_router = 1;
917
918         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
919                     (unsigned long)port);
920         setup_timer(&port->ip4_own_query.timer,
921                     br_ip4_multicast_port_query_expired, (unsigned long)port);
922 #if IS_ENABLED(CONFIG_IPV6)
923         setup_timer(&port->ip6_own_query.timer,
924                     br_ip6_multicast_port_query_expired, (unsigned long)port);
925 #endif
926 }
927
928 void br_multicast_del_port(struct net_bridge_port *port)
929 {
930         struct net_bridge *br = port->br;
931         struct net_bridge_port_group *pg;
932         struct hlist_node *n;
933
934         /* Take care of the remaining groups, only perm ones should be left */
935         spin_lock_bh(&br->multicast_lock);
936         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
937                 br_multicast_del_pg(br, pg);
938         spin_unlock_bh(&br->multicast_lock);
939         del_timer_sync(&port->multicast_router_timer);
940 }
941
942 static void br_multicast_enable(struct bridge_mcast_own_query *query)
943 {
944         query->startup_sent = 0;
945
946         if (try_to_del_timer_sync(&query->timer) >= 0 ||
947             del_timer(&query->timer))
948                 mod_timer(&query->timer, jiffies);
949 }
950
951 void br_multicast_enable_port(struct net_bridge_port *port)
952 {
953         struct net_bridge *br = port->br;
954
955         spin_lock(&br->multicast_lock);
956         if (br->multicast_disabled || !netif_running(br->dev))
957                 goto out;
958
959         br_multicast_enable(&port->ip4_own_query);
960 #if IS_ENABLED(CONFIG_IPV6)
961         br_multicast_enable(&port->ip6_own_query);
962 #endif
963         if (port->multicast_router == 2 && hlist_unhashed(&port->rlist))
964                 br_multicast_add_router(br, port);
965
966 out:
967         spin_unlock(&br->multicast_lock);
968 }
969
970 void br_multicast_disable_port(struct net_bridge_port *port)
971 {
972         struct net_bridge *br = port->br;
973         struct net_bridge_port_group *pg;
974         struct hlist_node *n;
975
976         spin_lock(&br->multicast_lock);
977         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
978                 if (pg->state == MDB_TEMPORARY)
979                         br_multicast_del_pg(br, pg);
980
981         if (!hlist_unhashed(&port->rlist)) {
982                 hlist_del_init_rcu(&port->rlist);
983                 br_rtr_notify(br->dev, port, RTM_DELMDB);
984         }
985         del_timer(&port->multicast_router_timer);
986         del_timer(&port->ip4_own_query.timer);
987 #if IS_ENABLED(CONFIG_IPV6)
988         del_timer(&port->ip6_own_query.timer);
989 #endif
990         spin_unlock(&br->multicast_lock);
991 }
992
993 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
994                                          struct net_bridge_port *port,
995                                          struct sk_buff *skb,
996                                          u16 vid)
997 {
998         struct igmpv3_report *ih;
999         struct igmpv3_grec *grec;
1000         int i;
1001         int len;
1002         int num;
1003         int type;
1004         int err = 0;
1005         __be32 group;
1006
1007         ih = igmpv3_report_hdr(skb);
1008         num = ntohs(ih->ngrec);
1009         len = skb_transport_offset(skb) + sizeof(*ih);
1010
1011         for (i = 0; i < num; i++) {
1012                 len += sizeof(*grec);
1013                 if (!pskb_may_pull(skb, len))
1014                         return -EINVAL;
1015
1016                 grec = (void *)(skb->data + len - sizeof(*grec));
1017                 group = grec->grec_mca;
1018                 type = grec->grec_type;
1019
1020                 len += ntohs(grec->grec_nsrcs) * 4;
1021                 if (!pskb_may_pull(skb, len))
1022                         return -EINVAL;
1023
1024                 /* We treat this as an IGMPv2 report for now. */
1025                 switch (type) {
1026                 case IGMPV3_MODE_IS_INCLUDE:
1027                 case IGMPV3_MODE_IS_EXCLUDE:
1028                 case IGMPV3_CHANGE_TO_INCLUDE:
1029                 case IGMPV3_CHANGE_TO_EXCLUDE:
1030                 case IGMPV3_ALLOW_NEW_SOURCES:
1031                 case IGMPV3_BLOCK_OLD_SOURCES:
1032                         break;
1033
1034                 default:
1035                         continue;
1036                 }
1037
1038                 if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
1039                      type == IGMPV3_MODE_IS_INCLUDE) &&
1040                     ntohs(grec->grec_nsrcs) == 0) {
1041                         br_ip4_multicast_leave_group(br, port, group, vid);
1042                 } else {
1043                         err = br_ip4_multicast_add_group(br, port, group, vid);
1044                         if (err)
1045                                 break;
1046                 }
1047         }
1048
1049         return err;
1050 }
1051
1052 #if IS_ENABLED(CONFIG_IPV6)
1053 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1054                                         struct net_bridge_port *port,
1055                                         struct sk_buff *skb,
1056                                         u16 vid)
1057 {
1058         struct icmp6hdr *icmp6h;
1059         struct mld2_grec *grec;
1060         int i;
1061         int len;
1062         int num;
1063         int err = 0;
1064
1065         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1066                 return -EINVAL;
1067
1068         icmp6h = icmp6_hdr(skb);
1069         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1070         len = skb_transport_offset(skb) + sizeof(*icmp6h);
1071
1072         for (i = 0; i < num; i++) {
1073                 __be16 *nsrcs, _nsrcs;
1074
1075                 nsrcs = skb_header_pointer(skb,
1076                                            len + offsetof(struct mld2_grec,
1077                                                           grec_nsrcs),
1078                                            sizeof(_nsrcs), &_nsrcs);
1079                 if (!nsrcs)
1080                         return -EINVAL;
1081
1082                 if (!pskb_may_pull(skb,
1083                                    len + sizeof(*grec) +
1084                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1085                         return -EINVAL;
1086
1087                 grec = (struct mld2_grec *)(skb->data + len);
1088                 len += sizeof(*grec) +
1089                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1090
1091                 /* We treat these as MLDv1 reports for now. */
1092                 switch (grec->grec_type) {
1093                 case MLD2_MODE_IS_INCLUDE:
1094                 case MLD2_MODE_IS_EXCLUDE:
1095                 case MLD2_CHANGE_TO_INCLUDE:
1096                 case MLD2_CHANGE_TO_EXCLUDE:
1097                 case MLD2_ALLOW_NEW_SOURCES:
1098                 case MLD2_BLOCK_OLD_SOURCES:
1099                         break;
1100
1101                 default:
1102                         continue;
1103                 }
1104
1105                 if ((grec->grec_type == MLD2_CHANGE_TO_INCLUDE ||
1106                      grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
1107                     ntohs(*nsrcs) == 0) {
1108                         br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
1109                                                      vid);
1110                 } else {
1111                         err = br_ip6_multicast_add_group(br, port,
1112                                                          &grec->grec_mca, vid);
1113                         if (!err)
1114                                 break;
1115                 }
1116         }
1117
1118         return err;
1119 }
1120 #endif
1121
1122 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1123                                             struct net_bridge_port *port,
1124                                             __be32 saddr)
1125 {
1126         if (!timer_pending(&br->ip4_own_query.timer) &&
1127             !timer_pending(&br->ip4_other_query.timer))
1128                 goto update;
1129
1130         if (!br->ip4_querier.addr.u.ip4)
1131                 goto update;
1132
1133         if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1134                 goto update;
1135
1136         return false;
1137
1138 update:
1139         br->ip4_querier.addr.u.ip4 = saddr;
1140
1141         /* update protected by general multicast_lock by caller */
1142         rcu_assign_pointer(br->ip4_querier.port, port);
1143
1144         return true;
1145 }
1146
1147 #if IS_ENABLED(CONFIG_IPV6)
1148 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1149                                             struct net_bridge_port *port,
1150                                             struct in6_addr *saddr)
1151 {
1152         if (!timer_pending(&br->ip6_own_query.timer) &&
1153             !timer_pending(&br->ip6_other_query.timer))
1154                 goto update;
1155
1156         if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1157                 goto update;
1158
1159         return false;
1160
1161 update:
1162         br->ip6_querier.addr.u.ip6 = *saddr;
1163
1164         /* update protected by general multicast_lock by caller */
1165         rcu_assign_pointer(br->ip6_querier.port, port);
1166
1167         return true;
1168 }
1169 #endif
1170
1171 static bool br_multicast_select_querier(struct net_bridge *br,
1172                                         struct net_bridge_port *port,
1173                                         struct br_ip *saddr)
1174 {
1175         switch (saddr->proto) {
1176         case htons(ETH_P_IP):
1177                 return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1178 #if IS_ENABLED(CONFIG_IPV6)
1179         case htons(ETH_P_IPV6):
1180                 return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1181 #endif
1182         }
1183
1184         return false;
1185 }
1186
1187 static void
1188 br_multicast_update_query_timer(struct net_bridge *br,
1189                                 struct bridge_mcast_other_query *query,
1190                                 unsigned long max_delay)
1191 {
1192         if (!timer_pending(&query->timer))
1193                 query->delay_time = jiffies + max_delay;
1194
1195         mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1196 }
1197
1198 /*
1199  * Add port to router_list
1200  *  list is maintained ordered by pointer value
1201  *  and locked by br->multicast_lock and RCU
1202  */
1203 static void br_multicast_add_router(struct net_bridge *br,
1204                                     struct net_bridge_port *port)
1205 {
1206         struct net_bridge_port *p;
1207         struct hlist_node *slot = NULL;
1208
1209         if (!hlist_unhashed(&port->rlist))
1210                 return;
1211
1212         hlist_for_each_entry(p, &br->router_list, rlist) {
1213                 if ((unsigned long) port >= (unsigned long) p)
1214                         break;
1215                 slot = &p->rlist;
1216         }
1217
1218         if (slot)
1219                 hlist_add_behind_rcu(&port->rlist, slot);
1220         else
1221                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1222         br_rtr_notify(br->dev, port, RTM_NEWMDB);
1223 }
1224
1225 static void br_multicast_mark_router(struct net_bridge *br,
1226                                      struct net_bridge_port *port)
1227 {
1228         unsigned long now = jiffies;
1229
1230         if (!port) {
1231                 if (br->multicast_router == 1)
1232                         mod_timer(&br->multicast_router_timer,
1233                                   now + br->multicast_querier_interval);
1234                 return;
1235         }
1236
1237         if (port->multicast_router != 1)
1238                 return;
1239
1240         br_multicast_add_router(br, port);
1241
1242         mod_timer(&port->multicast_router_timer,
1243                   now + br->multicast_querier_interval);
1244 }
1245
1246 static void br_multicast_query_received(struct net_bridge *br,
1247                                         struct net_bridge_port *port,
1248                                         struct bridge_mcast_other_query *query,
1249                                         struct br_ip *saddr,
1250                                         unsigned long max_delay)
1251 {
1252         if (!br_multicast_select_querier(br, port, saddr))
1253                 return;
1254
1255         br_multicast_update_query_timer(br, query, max_delay);
1256         br_multicast_mark_router(br, port);
1257 }
1258
1259 static int br_ip4_multicast_query(struct net_bridge *br,
1260                                   struct net_bridge_port *port,
1261                                   struct sk_buff *skb,
1262                                   u16 vid)
1263 {
1264         const struct iphdr *iph = ip_hdr(skb);
1265         struct igmphdr *ih = igmp_hdr(skb);
1266         struct net_bridge_mdb_entry *mp;
1267         struct igmpv3_query *ih3;
1268         struct net_bridge_port_group *p;
1269         struct net_bridge_port_group __rcu **pp;
1270         struct br_ip saddr;
1271         unsigned long max_delay;
1272         unsigned long now = jiffies;
1273         unsigned int offset = skb_transport_offset(skb);
1274         __be32 group;
1275         int err = 0;
1276
1277         spin_lock(&br->multicast_lock);
1278         if (!netif_running(br->dev) ||
1279             (port && port->state == BR_STATE_DISABLED))
1280                 goto out;
1281
1282         group = ih->group;
1283
1284         if (skb->len == offset + sizeof(*ih)) {
1285                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1286
1287                 if (!max_delay) {
1288                         max_delay = 10 * HZ;
1289                         group = 0;
1290                 }
1291         } else if (skb->len >= offset + sizeof(*ih3)) {
1292                 ih3 = igmpv3_query_hdr(skb);
1293                 if (ih3->nsrcs)
1294                         goto out;
1295
1296                 max_delay = ih3->code ?
1297                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1298         } else {
1299                 goto out;
1300         }
1301
1302         if (!group) {
1303                 saddr.proto = htons(ETH_P_IP);
1304                 saddr.u.ip4 = iph->saddr;
1305
1306                 br_multicast_query_received(br, port, &br->ip4_other_query,
1307                                             &saddr, max_delay);
1308                 goto out;
1309         }
1310
1311         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1312         if (!mp)
1313                 goto out;
1314
1315         max_delay *= br->multicast_last_member_count;
1316
1317         if (mp->mglist &&
1318             (timer_pending(&mp->timer) ?
1319              time_after(mp->timer.expires, now + max_delay) :
1320              try_to_del_timer_sync(&mp->timer) >= 0))
1321                 mod_timer(&mp->timer, now + max_delay);
1322
1323         for (pp = &mp->ports;
1324              (p = mlock_dereference(*pp, br)) != NULL;
1325              pp = &p->next) {
1326                 if (timer_pending(&p->timer) ?
1327                     time_after(p->timer.expires, now + max_delay) :
1328                     try_to_del_timer_sync(&p->timer) >= 0)
1329                         mod_timer(&p->timer, now + max_delay);
1330         }
1331
1332 out:
1333         spin_unlock(&br->multicast_lock);
1334         return err;
1335 }
1336
1337 #if IS_ENABLED(CONFIG_IPV6)
1338 static int br_ip6_multicast_query(struct net_bridge *br,
1339                                   struct net_bridge_port *port,
1340                                   struct sk_buff *skb,
1341                                   u16 vid)
1342 {
1343         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1344         struct mld_msg *mld;
1345         struct net_bridge_mdb_entry *mp;
1346         struct mld2_query *mld2q;
1347         struct net_bridge_port_group *p;
1348         struct net_bridge_port_group __rcu **pp;
1349         struct br_ip saddr;
1350         unsigned long max_delay;
1351         unsigned long now = jiffies;
1352         unsigned int offset = skb_transport_offset(skb);
1353         const struct in6_addr *group = NULL;
1354         bool is_general_query;
1355         int err = 0;
1356
1357         spin_lock(&br->multicast_lock);
1358         if (!netif_running(br->dev) ||
1359             (port && port->state == BR_STATE_DISABLED))
1360                 goto out;
1361
1362         if (skb->len == offset + sizeof(*mld)) {
1363                 if (!pskb_may_pull(skb, offset + sizeof(*mld))) {
1364                         err = -EINVAL;
1365                         goto out;
1366                 }
1367                 mld = (struct mld_msg *) icmp6_hdr(skb);
1368                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1369                 if (max_delay)
1370                         group = &mld->mld_mca;
1371         } else {
1372                 if (!pskb_may_pull(skb, offset + sizeof(*mld2q))) {
1373                         err = -EINVAL;
1374                         goto out;
1375                 }
1376                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1377                 if (!mld2q->mld2q_nsrcs)
1378                         group = &mld2q->mld2q_mca;
1379
1380                 max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1381         }
1382
1383         is_general_query = group && ipv6_addr_any(group);
1384
1385         if (is_general_query) {
1386                 saddr.proto = htons(ETH_P_IPV6);
1387                 saddr.u.ip6 = ip6h->saddr;
1388
1389                 br_multicast_query_received(br, port, &br->ip6_other_query,
1390                                             &saddr, max_delay);
1391                 goto out;
1392         } else if (!group) {
1393                 goto out;
1394         }
1395
1396         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1397         if (!mp)
1398                 goto out;
1399
1400         max_delay *= br->multicast_last_member_count;
1401         if (mp->mglist &&
1402             (timer_pending(&mp->timer) ?
1403              time_after(mp->timer.expires, now + max_delay) :
1404              try_to_del_timer_sync(&mp->timer) >= 0))
1405                 mod_timer(&mp->timer, now + max_delay);
1406
1407         for (pp = &mp->ports;
1408              (p = mlock_dereference(*pp, br)) != NULL;
1409              pp = &p->next) {
1410                 if (timer_pending(&p->timer) ?
1411                     time_after(p->timer.expires, now + max_delay) :
1412                     try_to_del_timer_sync(&p->timer) >= 0)
1413                         mod_timer(&p->timer, now + max_delay);
1414         }
1415
1416 out:
1417         spin_unlock(&br->multicast_lock);
1418         return err;
1419 }
1420 #endif
1421
1422 static void
1423 br_multicast_leave_group(struct net_bridge *br,
1424                          struct net_bridge_port *port,
1425                          struct br_ip *group,
1426                          struct bridge_mcast_other_query *other_query,
1427                          struct bridge_mcast_own_query *own_query)
1428 {
1429         struct net_bridge_mdb_htable *mdb;
1430         struct net_bridge_mdb_entry *mp;
1431         struct net_bridge_port_group *p;
1432         unsigned long now;
1433         unsigned long time;
1434
1435         spin_lock(&br->multicast_lock);
1436         if (!netif_running(br->dev) ||
1437             (port && port->state == BR_STATE_DISABLED))
1438                 goto out;
1439
1440         mdb = mlock_dereference(br->mdb, br);
1441         mp = br_mdb_ip_get(mdb, group);
1442         if (!mp)
1443                 goto out;
1444
1445         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1446                 struct net_bridge_port_group __rcu **pp;
1447
1448                 for (pp = &mp->ports;
1449                      (p = mlock_dereference(*pp, br)) != NULL;
1450                      pp = &p->next) {
1451                         if (p->port != port)
1452                                 continue;
1453
1454                         rcu_assign_pointer(*pp, p->next);
1455                         hlist_del_init(&p->mglist);
1456                         del_timer(&p->timer);
1457                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1458                         br_mdb_notify(br->dev, port, group, RTM_DELMDB,
1459                                       p->state);
1460
1461                         if (!mp->ports && !mp->mglist &&
1462                             netif_running(br->dev))
1463                                 mod_timer(&mp->timer, jiffies);
1464                 }
1465                 goto out;
1466         }
1467
1468         if (timer_pending(&other_query->timer))
1469                 goto out;
1470
1471         if (br->multicast_querier) {
1472                 __br_multicast_send_query(br, port, &mp->addr);
1473
1474                 time = jiffies + br->multicast_last_member_count *
1475                                  br->multicast_last_member_interval;
1476
1477                 mod_timer(&own_query->timer, time);
1478
1479                 for (p = mlock_dereference(mp->ports, br);
1480                      p != NULL;
1481                      p = mlock_dereference(p->next, br)) {
1482                         if (p->port != port)
1483                                 continue;
1484
1485                         if (!hlist_unhashed(&p->mglist) &&
1486                             (timer_pending(&p->timer) ?
1487                              time_after(p->timer.expires, time) :
1488                              try_to_del_timer_sync(&p->timer) >= 0)) {
1489                                 mod_timer(&p->timer, time);
1490                         }
1491
1492                         break;
1493                 }
1494         }
1495
1496         now = jiffies;
1497         time = now + br->multicast_last_member_count *
1498                      br->multicast_last_member_interval;
1499
1500         if (!port) {
1501                 if (mp->mglist &&
1502                     (timer_pending(&mp->timer) ?
1503                      time_after(mp->timer.expires, time) :
1504                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1505                         mod_timer(&mp->timer, time);
1506                 }
1507
1508                 goto out;
1509         }
1510
1511         for (p = mlock_dereference(mp->ports, br);
1512              p != NULL;
1513              p = mlock_dereference(p->next, br)) {
1514                 if (p->port != port)
1515                         continue;
1516
1517                 if (!hlist_unhashed(&p->mglist) &&
1518                     (timer_pending(&p->timer) ?
1519                      time_after(p->timer.expires, time) :
1520                      try_to_del_timer_sync(&p->timer) >= 0)) {
1521                         mod_timer(&p->timer, time);
1522                 }
1523
1524                 break;
1525         }
1526 out:
1527         spin_unlock(&br->multicast_lock);
1528 }
1529
1530 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1531                                          struct net_bridge_port *port,
1532                                          __be32 group,
1533                                          __u16 vid)
1534 {
1535         struct br_ip br_group;
1536         struct bridge_mcast_own_query *own_query;
1537
1538         if (ipv4_is_local_multicast(group))
1539                 return;
1540
1541         own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1542
1543         br_group.u.ip4 = group;
1544         br_group.proto = htons(ETH_P_IP);
1545         br_group.vid = vid;
1546
1547         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1548                                  own_query);
1549 }
1550
1551 #if IS_ENABLED(CONFIG_IPV6)
1552 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1553                                          struct net_bridge_port *port,
1554                                          const struct in6_addr *group,
1555                                          __u16 vid)
1556 {
1557         struct br_ip br_group;
1558         struct bridge_mcast_own_query *own_query;
1559
1560         if (ipv6_addr_is_ll_all_nodes(group))
1561                 return;
1562
1563         own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1564
1565         br_group.u.ip6 = *group;
1566         br_group.proto = htons(ETH_P_IPV6);
1567         br_group.vid = vid;
1568
1569         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1570                                  own_query);
1571 }
1572 #endif
1573
1574 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1575                                  struct net_bridge_port *port,
1576                                  struct sk_buff *skb,
1577                                  u16 vid)
1578 {
1579         struct sk_buff *skb_trimmed = NULL;
1580         struct igmphdr *ih;
1581         int err;
1582
1583         err = ip_mc_check_igmp(skb, &skb_trimmed);
1584
1585         if (err == -ENOMSG) {
1586                 if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr))
1587                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1588                 return 0;
1589         } else if (err < 0) {
1590                 return err;
1591         }
1592
1593         BR_INPUT_SKB_CB(skb)->igmp = 1;
1594         ih = igmp_hdr(skb);
1595
1596         switch (ih->type) {
1597         case IGMP_HOST_MEMBERSHIP_REPORT:
1598         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1599                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1600                 err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1601                 break;
1602         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1603                 err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
1604                 break;
1605         case IGMP_HOST_MEMBERSHIP_QUERY:
1606                 err = br_ip4_multicast_query(br, port, skb_trimmed, vid);
1607                 break;
1608         case IGMP_HOST_LEAVE_MESSAGE:
1609                 br_ip4_multicast_leave_group(br, port, ih->group, vid);
1610                 break;
1611         }
1612
1613         if (skb_trimmed && skb_trimmed != skb)
1614                 kfree_skb(skb_trimmed);
1615
1616         return err;
1617 }
1618
1619 #if IS_ENABLED(CONFIG_IPV6)
1620 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1621                                  struct net_bridge_port *port,
1622                                  struct sk_buff *skb,
1623                                  u16 vid)
1624 {
1625         struct sk_buff *skb_trimmed = NULL;
1626         struct mld_msg *mld;
1627         int err;
1628
1629         err = ipv6_mc_check_mld(skb, &skb_trimmed);
1630
1631         if (err == -ENOMSG) {
1632                 if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
1633                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1634                 return 0;
1635         } else if (err < 0) {
1636                 return err;
1637         }
1638
1639         BR_INPUT_SKB_CB(skb)->igmp = 1;
1640         mld = (struct mld_msg *)skb_transport_header(skb);
1641
1642         switch (mld->mld_type) {
1643         case ICMPV6_MGM_REPORT:
1644                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1645                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1646                 break;
1647         case ICMPV6_MLD2_REPORT:
1648                 err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
1649                 break;
1650         case ICMPV6_MGM_QUERY:
1651                 err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
1652                 break;
1653         case ICMPV6_MGM_REDUCTION:
1654                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1655                 break;
1656         }
1657
1658         if (skb_trimmed && skb_trimmed != skb)
1659                 kfree_skb(skb_trimmed);
1660
1661         return err;
1662 }
1663 #endif
1664
1665 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1666                      struct sk_buff *skb, u16 vid)
1667 {
1668         BR_INPUT_SKB_CB(skb)->igmp = 0;
1669         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1670
1671         if (br->multicast_disabled)
1672                 return 0;
1673
1674         switch (skb->protocol) {
1675         case htons(ETH_P_IP):
1676                 return br_multicast_ipv4_rcv(br, port, skb, vid);
1677 #if IS_ENABLED(CONFIG_IPV6)
1678         case htons(ETH_P_IPV6):
1679                 return br_multicast_ipv6_rcv(br, port, skb, vid);
1680 #endif
1681         }
1682
1683         return 0;
1684 }
1685
1686 static void br_multicast_query_expired(struct net_bridge *br,
1687                                        struct bridge_mcast_own_query *query,
1688                                        struct bridge_mcast_querier *querier)
1689 {
1690         spin_lock(&br->multicast_lock);
1691         if (query->startup_sent < br->multicast_startup_query_count)
1692                 query->startup_sent++;
1693
1694         RCU_INIT_POINTER(querier->port, NULL);
1695         br_multicast_send_query(br, NULL, query);
1696         spin_unlock(&br->multicast_lock);
1697 }
1698
1699 static void br_ip4_multicast_query_expired(unsigned long data)
1700 {
1701         struct net_bridge *br = (void *)data;
1702
1703         br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1704 }
1705
1706 #if IS_ENABLED(CONFIG_IPV6)
1707 static void br_ip6_multicast_query_expired(unsigned long data)
1708 {
1709         struct net_bridge *br = (void *)data;
1710
1711         br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1712 }
1713 #endif
1714
1715 void br_multicast_init(struct net_bridge *br)
1716 {
1717         br->hash_elasticity = 4;
1718         br->hash_max = 512;
1719
1720         br->multicast_router = 1;
1721         br->multicast_querier = 0;
1722         br->multicast_query_use_ifaddr = 0;
1723         br->multicast_last_member_count = 2;
1724         br->multicast_startup_query_count = 2;
1725
1726         br->multicast_last_member_interval = HZ;
1727         br->multicast_query_response_interval = 10 * HZ;
1728         br->multicast_startup_query_interval = 125 * HZ / 4;
1729         br->multicast_query_interval = 125 * HZ;
1730         br->multicast_querier_interval = 255 * HZ;
1731         br->multicast_membership_interval = 260 * HZ;
1732
1733         br->ip4_other_query.delay_time = 0;
1734         br->ip4_querier.port = NULL;
1735 #if IS_ENABLED(CONFIG_IPV6)
1736         br->ip6_other_query.delay_time = 0;
1737         br->ip6_querier.port = NULL;
1738 #endif
1739
1740         spin_lock_init(&br->multicast_lock);
1741         setup_timer(&br->multicast_router_timer,
1742                     br_multicast_local_router_expired, 0);
1743         setup_timer(&br->ip4_other_query.timer,
1744                     br_ip4_multicast_querier_expired, (unsigned long)br);
1745         setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1746                     (unsigned long)br);
1747 #if IS_ENABLED(CONFIG_IPV6)
1748         setup_timer(&br->ip6_other_query.timer,
1749                     br_ip6_multicast_querier_expired, (unsigned long)br);
1750         setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1751                     (unsigned long)br);
1752 #endif
1753 }
1754
1755 static void __br_multicast_open(struct net_bridge *br,
1756                                 struct bridge_mcast_own_query *query)
1757 {
1758         query->startup_sent = 0;
1759
1760         if (br->multicast_disabled)
1761                 return;
1762
1763         mod_timer(&query->timer, jiffies);
1764 }
1765
1766 void br_multicast_open(struct net_bridge *br)
1767 {
1768         __br_multicast_open(br, &br->ip4_own_query);
1769 #if IS_ENABLED(CONFIG_IPV6)
1770         __br_multicast_open(br, &br->ip6_own_query);
1771 #endif
1772 }
1773
1774 void br_multicast_stop(struct net_bridge *br)
1775 {
1776         del_timer_sync(&br->multicast_router_timer);
1777         del_timer_sync(&br->ip4_other_query.timer);
1778         del_timer_sync(&br->ip4_own_query.timer);
1779 #if IS_ENABLED(CONFIG_IPV6)
1780         del_timer_sync(&br->ip6_other_query.timer);
1781         del_timer_sync(&br->ip6_own_query.timer);
1782 #endif
1783 }
1784
1785 void br_multicast_dev_del(struct net_bridge *br)
1786 {
1787         struct net_bridge_mdb_htable *mdb;
1788         struct net_bridge_mdb_entry *mp;
1789         struct hlist_node *n;
1790         u32 ver;
1791         int i;
1792
1793         spin_lock_bh(&br->multicast_lock);
1794         mdb = mlock_dereference(br->mdb, br);
1795         if (!mdb)
1796                 goto out;
1797
1798         br->mdb = NULL;
1799
1800         ver = mdb->ver;
1801         for (i = 0; i < mdb->max; i++) {
1802                 hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1803                                           hlist[ver]) {
1804                         del_timer(&mp->timer);
1805                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1806                 }
1807         }
1808
1809         if (mdb->old) {
1810                 spin_unlock_bh(&br->multicast_lock);
1811                 rcu_barrier_bh();
1812                 spin_lock_bh(&br->multicast_lock);
1813                 WARN_ON(mdb->old);
1814         }
1815
1816         mdb->old = mdb;
1817         call_rcu_bh(&mdb->rcu, br_mdb_free);
1818
1819 out:
1820         spin_unlock_bh(&br->multicast_lock);
1821 }
1822
1823 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1824 {
1825         int err = -EINVAL;
1826
1827         spin_lock_bh(&br->multicast_lock);
1828
1829         switch (val) {
1830         case 0:
1831         case 2:
1832                 del_timer(&br->multicast_router_timer);
1833                 /* fall through */
1834         case 1:
1835                 br->multicast_router = val;
1836                 err = 0;
1837                 break;
1838         }
1839
1840         spin_unlock_bh(&br->multicast_lock);
1841
1842         return err;
1843 }
1844
1845 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1846 {
1847         struct net_bridge *br = p->br;
1848         int err = -EINVAL;
1849
1850         spin_lock(&br->multicast_lock);
1851
1852         switch (val) {
1853         case 0:
1854         case 1:
1855         case 2:
1856                 p->multicast_router = val;
1857                 err = 0;
1858
1859                 if (val < 2 && !hlist_unhashed(&p->rlist)) {
1860                         hlist_del_init_rcu(&p->rlist);
1861                         br_rtr_notify(br->dev, p, RTM_DELMDB);
1862                 }
1863
1864                 if (val == 1)
1865                         break;
1866
1867                 del_timer(&p->multicast_router_timer);
1868
1869                 if (val == 0)
1870                         break;
1871
1872                 br_multicast_add_router(br, p);
1873                 break;
1874         }
1875
1876         spin_unlock(&br->multicast_lock);
1877
1878         return err;
1879 }
1880
1881 static void br_multicast_start_querier(struct net_bridge *br,
1882                                        struct bridge_mcast_own_query *query)
1883 {
1884         struct net_bridge_port *port;
1885
1886         __br_multicast_open(br, query);
1887
1888         list_for_each_entry(port, &br->port_list, list) {
1889                 if (port->state == BR_STATE_DISABLED ||
1890                     port->state == BR_STATE_BLOCKING)
1891                         continue;
1892
1893                 if (query == &br->ip4_own_query)
1894                         br_multicast_enable(&port->ip4_own_query);
1895 #if IS_ENABLED(CONFIG_IPV6)
1896                 else
1897                         br_multicast_enable(&port->ip6_own_query);
1898 #endif
1899         }
1900 }
1901
1902 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1903 {
1904         int err = 0;
1905         struct net_bridge_mdb_htable *mdb;
1906
1907         spin_lock_bh(&br->multicast_lock);
1908         if (br->multicast_disabled == !val)
1909                 goto unlock;
1910
1911         br->multicast_disabled = !val;
1912         if (br->multicast_disabled)
1913                 goto unlock;
1914
1915         if (!netif_running(br->dev))
1916                 goto unlock;
1917
1918         mdb = mlock_dereference(br->mdb, br);
1919         if (mdb) {
1920                 if (mdb->old) {
1921                         err = -EEXIST;
1922 rollback:
1923                         br->multicast_disabled = !!val;
1924                         goto unlock;
1925                 }
1926
1927                 err = br_mdb_rehash(&br->mdb, mdb->max,
1928                                     br->hash_elasticity);
1929                 if (err)
1930                         goto rollback;
1931         }
1932
1933         br_multicast_start_querier(br, &br->ip4_own_query);
1934 #if IS_ENABLED(CONFIG_IPV6)
1935         br_multicast_start_querier(br, &br->ip6_own_query);
1936 #endif
1937
1938 unlock:
1939         spin_unlock_bh(&br->multicast_lock);
1940
1941         return err;
1942 }
1943
1944 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1945 {
1946         unsigned long max_delay;
1947
1948         val = !!val;
1949
1950         spin_lock_bh(&br->multicast_lock);
1951         if (br->multicast_querier == val)
1952                 goto unlock;
1953
1954         br->multicast_querier = val;
1955         if (!val)
1956                 goto unlock;
1957
1958         max_delay = br->multicast_query_response_interval;
1959
1960         if (!timer_pending(&br->ip4_other_query.timer))
1961                 br->ip4_other_query.delay_time = jiffies + max_delay;
1962
1963         br_multicast_start_querier(br, &br->ip4_own_query);
1964
1965 #if IS_ENABLED(CONFIG_IPV6)
1966         if (!timer_pending(&br->ip6_other_query.timer))
1967                 br->ip6_other_query.delay_time = jiffies + max_delay;
1968
1969         br_multicast_start_querier(br, &br->ip6_own_query);
1970 #endif
1971
1972 unlock:
1973         spin_unlock_bh(&br->multicast_lock);
1974
1975         return 0;
1976 }
1977
1978 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1979 {
1980         int err = -EINVAL;
1981         u32 old;
1982         struct net_bridge_mdb_htable *mdb;
1983
1984         spin_lock_bh(&br->multicast_lock);
1985         if (!is_power_of_2(val))
1986                 goto unlock;
1987
1988         mdb = mlock_dereference(br->mdb, br);
1989         if (mdb && val < mdb->size)
1990                 goto unlock;
1991
1992         err = 0;
1993
1994         old = br->hash_max;
1995         br->hash_max = val;
1996
1997         if (mdb) {
1998                 if (mdb->old) {
1999                         err = -EEXIST;
2000 rollback:
2001                         br->hash_max = old;
2002                         goto unlock;
2003                 }
2004
2005                 err = br_mdb_rehash(&br->mdb, br->hash_max,
2006                                     br->hash_elasticity);
2007                 if (err)
2008                         goto rollback;
2009         }
2010
2011 unlock:
2012         spin_unlock_bh(&br->multicast_lock);
2013
2014         return err;
2015 }
2016
2017 /**
2018  * br_multicast_list_adjacent - Returns snooped multicast addresses
2019  * @dev:        The bridge port adjacent to which to retrieve addresses
2020  * @br_ip_list: The list to store found, snooped multicast IP addresses in
2021  *
2022  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2023  * snooping feature on all bridge ports of dev's bridge device, excluding
2024  * the addresses from dev itself.
2025  *
2026  * Returns the number of items added to br_ip_list.
2027  *
2028  * Notes:
2029  * - br_ip_list needs to be initialized by caller
2030  * - br_ip_list might contain duplicates in the end
2031  *   (needs to be taken care of by caller)
2032  * - br_ip_list needs to be freed by caller
2033  */
2034 int br_multicast_list_adjacent(struct net_device *dev,
2035                                struct list_head *br_ip_list)
2036 {
2037         struct net_bridge *br;
2038         struct net_bridge_port *port;
2039         struct net_bridge_port_group *group;
2040         struct br_ip_list *entry;
2041         int count = 0;
2042
2043         rcu_read_lock();
2044         if (!br_ip_list || !br_port_exists(dev))
2045                 goto unlock;
2046
2047         port = br_port_get_rcu(dev);
2048         if (!port || !port->br)
2049                 goto unlock;
2050
2051         br = port->br;
2052
2053         list_for_each_entry_rcu(port, &br->port_list, list) {
2054                 if (!port->dev || port->dev == dev)
2055                         continue;
2056
2057                 hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2058                         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2059                         if (!entry)
2060                                 goto unlock;
2061
2062                         entry->addr = group->addr;
2063                         list_add(&entry->list, br_ip_list);
2064                         count++;
2065                 }
2066         }
2067
2068 unlock:
2069         rcu_read_unlock();
2070         return count;
2071 }
2072 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2073
2074 /**
2075  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2076  * @dev: The bridge port providing the bridge on which to check for a querier
2077  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2078  *
2079  * Checks whether the given interface has a bridge on top and if so returns
2080  * true if a valid querier exists anywhere on the bridged link layer.
2081  * Otherwise returns false.
2082  */
2083 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2084 {
2085         struct net_bridge *br;
2086         struct net_bridge_port *port;
2087         struct ethhdr eth;
2088         bool ret = false;
2089
2090         rcu_read_lock();
2091         if (!br_port_exists(dev))
2092                 goto unlock;
2093
2094         port = br_port_get_rcu(dev);
2095         if (!port || !port->br)
2096                 goto unlock;
2097
2098         br = port->br;
2099
2100         memset(&eth, 0, sizeof(eth));
2101         eth.h_proto = htons(proto);
2102
2103         ret = br_multicast_querier_exists(br, &eth);
2104
2105 unlock:
2106         rcu_read_unlock();
2107         return ret;
2108 }
2109 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2110
2111 /**
2112  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2113  * @dev: The bridge port adjacent to which to check for a querier
2114  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2115  *
2116  * Checks whether the given interface has a bridge on top and if so returns
2117  * true if a selected querier is behind one of the other ports of this
2118  * bridge. Otherwise returns false.
2119  */
2120 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2121 {
2122         struct net_bridge *br;
2123         struct net_bridge_port *port;
2124         bool ret = false;
2125
2126         rcu_read_lock();
2127         if (!br_port_exists(dev))
2128                 goto unlock;
2129
2130         port = br_port_get_rcu(dev);
2131         if (!port || !port->br)
2132                 goto unlock;
2133
2134         br = port->br;
2135
2136         switch (proto) {
2137         case ETH_P_IP:
2138                 if (!timer_pending(&br->ip4_other_query.timer) ||
2139                     rcu_dereference(br->ip4_querier.port) == port)
2140                         goto unlock;
2141                 break;
2142 #if IS_ENABLED(CONFIG_IPV6)
2143         case ETH_P_IPV6:
2144                 if (!timer_pending(&br->ip6_other_query.timer) ||
2145                     rcu_dereference(br->ip6_querier.port) == port)
2146                         goto unlock;
2147                 break;
2148 #endif
2149         default:
2150                 goto unlock;
2151         }
2152
2153         ret = true;
2154 unlock:
2155         rcu_read_unlock();
2156         return ret;
2157 }
2158 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);