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Merge tag 'iio-fixes-for-3.19a' of git://git.kernel.org/pub/scm/linux/kernel/git...
[karo-tx-linux.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 unsigned int br_mdb_rehash_seq;
41
42 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
43 {
44         if (a->proto != b->proto)
45                 return 0;
46         if (a->vid != b->vid)
47                 return 0;
48         switch (a->proto) {
49         case htons(ETH_P_IP):
50                 return a->u.ip4 == b->u.ip4;
51 #if IS_ENABLED(CONFIG_IPV6)
52         case htons(ETH_P_IPV6):
53                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
54 #endif
55         }
56         return 0;
57 }
58
59 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
60                                 __u16 vid)
61 {
62         return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
63 }
64
65 #if IS_ENABLED(CONFIG_IPV6)
66 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
67                                 const struct in6_addr *ip,
68                                 __u16 vid)
69 {
70         return jhash_2words(ipv6_addr_hash(ip), vid,
71                             mdb->secret) & (mdb->max - 1);
72 }
73 #endif
74
75 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
76                              struct br_ip *ip)
77 {
78         switch (ip->proto) {
79         case htons(ETH_P_IP):
80                 return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
81 #if IS_ENABLED(CONFIG_IPV6)
82         case htons(ETH_P_IPV6):
83                 return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
84 #endif
85         }
86         return 0;
87 }
88
89 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
90         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
91 {
92         struct net_bridge_mdb_entry *mp;
93
94         hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
95                 if (br_ip_equal(&mp->addr, dst))
96                         return mp;
97         }
98
99         return NULL;
100 }
101
102 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
103                                            struct br_ip *dst)
104 {
105         if (!mdb)
106                 return NULL;
107
108         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
109 }
110
111 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
112         struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
113 {
114         struct br_ip br_dst;
115
116         br_dst.u.ip4 = dst;
117         br_dst.proto = htons(ETH_P_IP);
118         br_dst.vid = vid;
119
120         return br_mdb_ip_get(mdb, &br_dst);
121 }
122
123 #if IS_ENABLED(CONFIG_IPV6)
124 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
125         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
126         __u16 vid)
127 {
128         struct br_ip br_dst;
129
130         br_dst.u.ip6 = *dst;
131         br_dst.proto = htons(ETH_P_IPV6);
132         br_dst.vid = vid;
133
134         return br_mdb_ip_get(mdb, &br_dst);
135 }
136 #endif
137
138 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
139                                         struct sk_buff *skb, u16 vid)
140 {
141         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
142         struct br_ip ip;
143
144         if (br->multicast_disabled)
145                 return NULL;
146
147         if (BR_INPUT_SKB_CB(skb)->igmp)
148                 return NULL;
149
150         ip.proto = skb->protocol;
151         ip.vid = vid;
152
153         switch (skb->protocol) {
154         case htons(ETH_P_IP):
155                 ip.u.ip4 = ip_hdr(skb)->daddr;
156                 break;
157 #if IS_ENABLED(CONFIG_IPV6)
158         case htons(ETH_P_IPV6):
159                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
160                 break;
161 #endif
162         default:
163                 return NULL;
164         }
165
166         return br_mdb_ip_get(mdb, &ip);
167 }
168
169 static void br_mdb_free(struct rcu_head *head)
170 {
171         struct net_bridge_mdb_htable *mdb =
172                 container_of(head, struct net_bridge_mdb_htable, rcu);
173         struct net_bridge_mdb_htable *old = mdb->old;
174
175         mdb->old = NULL;
176         kfree(old->mhash);
177         kfree(old);
178 }
179
180 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
181                        struct net_bridge_mdb_htable *old,
182                        int elasticity)
183 {
184         struct net_bridge_mdb_entry *mp;
185         int maxlen;
186         int len;
187         int i;
188
189         for (i = 0; i < old->max; i++)
190                 hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
191                         hlist_add_head(&mp->hlist[new->ver],
192                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
193
194         if (!elasticity)
195                 return 0;
196
197         maxlen = 0;
198         for (i = 0; i < new->max; i++) {
199                 len = 0;
200                 hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
201                         len++;
202                 if (len > maxlen)
203                         maxlen = len;
204         }
205
206         return maxlen > elasticity ? -EINVAL : 0;
207 }
208
209 void br_multicast_free_pg(struct rcu_head *head)
210 {
211         struct net_bridge_port_group *p =
212                 container_of(head, struct net_bridge_port_group, rcu);
213
214         kfree(p);
215 }
216
217 static void br_multicast_free_group(struct rcu_head *head)
218 {
219         struct net_bridge_mdb_entry *mp =
220                 container_of(head, struct net_bridge_mdb_entry, rcu);
221
222         kfree(mp);
223 }
224
225 static void br_multicast_group_expired(unsigned long data)
226 {
227         struct net_bridge_mdb_entry *mp = (void *)data;
228         struct net_bridge *br = mp->br;
229         struct net_bridge_mdb_htable *mdb;
230
231         spin_lock(&br->multicast_lock);
232         if (!netif_running(br->dev) || timer_pending(&mp->timer))
233                 goto out;
234
235         mp->mglist = false;
236
237         if (mp->ports)
238                 goto out;
239
240         mdb = mlock_dereference(br->mdb, br);
241
242         hlist_del_rcu(&mp->hlist[mdb->ver]);
243         mdb->size--;
244
245         call_rcu_bh(&mp->rcu, br_multicast_free_group);
246
247 out:
248         spin_unlock(&br->multicast_lock);
249 }
250
251 static void br_multicast_del_pg(struct net_bridge *br,
252                                 struct net_bridge_port_group *pg)
253 {
254         struct net_bridge_mdb_htable *mdb;
255         struct net_bridge_mdb_entry *mp;
256         struct net_bridge_port_group *p;
257         struct net_bridge_port_group __rcu **pp;
258
259         mdb = mlock_dereference(br->mdb, br);
260
261         mp = br_mdb_ip_get(mdb, &pg->addr);
262         if (WARN_ON(!mp))
263                 return;
264
265         for (pp = &mp->ports;
266              (p = mlock_dereference(*pp, br)) != NULL;
267              pp = &p->next) {
268                 if (p != pg)
269                         continue;
270
271                 rcu_assign_pointer(*pp, p->next);
272                 hlist_del_init(&p->mglist);
273                 del_timer(&p->timer);
274                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
275
276                 if (!mp->ports && !mp->mglist &&
277                     netif_running(br->dev))
278                         mod_timer(&mp->timer, jiffies);
279
280                 return;
281         }
282
283         WARN_ON(1);
284 }
285
286 static void br_multicast_port_group_expired(unsigned long data)
287 {
288         struct net_bridge_port_group *pg = (void *)data;
289         struct net_bridge *br = pg->port->br;
290
291         spin_lock(&br->multicast_lock);
292         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
293             hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
294                 goto out;
295
296         br_multicast_del_pg(br, pg);
297
298 out:
299         spin_unlock(&br->multicast_lock);
300 }
301
302 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
303                          int elasticity)
304 {
305         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
306         struct net_bridge_mdb_htable *mdb;
307         int err;
308
309         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
310         if (!mdb)
311                 return -ENOMEM;
312
313         mdb->max = max;
314         mdb->old = old;
315
316         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
317         if (!mdb->mhash) {
318                 kfree(mdb);
319                 return -ENOMEM;
320         }
321
322         mdb->size = old ? old->size : 0;
323         mdb->ver = old ? old->ver ^ 1 : 0;
324
325         if (!old || elasticity)
326                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
327         else
328                 mdb->secret = old->secret;
329
330         if (!old)
331                 goto out;
332
333         err = br_mdb_copy(mdb, old, elasticity);
334         if (err) {
335                 kfree(mdb->mhash);
336                 kfree(mdb);
337                 return err;
338         }
339
340         br_mdb_rehash_seq++;
341         call_rcu_bh(&mdb->rcu, br_mdb_free);
342
343 out:
344         rcu_assign_pointer(*mdbp, mdb);
345
346         return 0;
347 }
348
349 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
350                                                     __be32 group)
351 {
352         struct sk_buff *skb;
353         struct igmphdr *ih;
354         struct ethhdr *eth;
355         struct iphdr *iph;
356
357         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
358                                                  sizeof(*ih) + 4);
359         if (!skb)
360                 goto out;
361
362         skb->protocol = htons(ETH_P_IP);
363
364         skb_reset_mac_header(skb);
365         eth = eth_hdr(skb);
366
367         ether_addr_copy(eth->h_source, br->dev->dev_addr);
368         eth->h_dest[0] = 1;
369         eth->h_dest[1] = 0;
370         eth->h_dest[2] = 0x5e;
371         eth->h_dest[3] = 0;
372         eth->h_dest[4] = 0;
373         eth->h_dest[5] = 1;
374         eth->h_proto = htons(ETH_P_IP);
375         skb_put(skb, sizeof(*eth));
376
377         skb_set_network_header(skb, skb->len);
378         iph = ip_hdr(skb);
379
380         iph->version = 4;
381         iph->ihl = 6;
382         iph->tos = 0xc0;
383         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
384         iph->id = 0;
385         iph->frag_off = htons(IP_DF);
386         iph->ttl = 1;
387         iph->protocol = IPPROTO_IGMP;
388         iph->saddr = br->multicast_query_use_ifaddr ?
389                      inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
390         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
391         ((u8 *)&iph[1])[0] = IPOPT_RA;
392         ((u8 *)&iph[1])[1] = 4;
393         ((u8 *)&iph[1])[2] = 0;
394         ((u8 *)&iph[1])[3] = 0;
395         ip_send_check(iph);
396         skb_put(skb, 24);
397
398         skb_set_transport_header(skb, skb->len);
399         ih = igmp_hdr(skb);
400         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
401         ih->code = (group ? br->multicast_last_member_interval :
402                             br->multicast_query_response_interval) /
403                    (HZ / IGMP_TIMER_SCALE);
404         ih->group = group;
405         ih->csum = 0;
406         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
407         skb_put(skb, sizeof(*ih));
408
409         __skb_pull(skb, sizeof(*eth));
410
411 out:
412         return skb;
413 }
414
415 #if IS_ENABLED(CONFIG_IPV6)
416 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
417                                                     const struct in6_addr *group)
418 {
419         struct sk_buff *skb;
420         struct ipv6hdr *ip6h;
421         struct mld_msg *mldq;
422         struct ethhdr *eth;
423         u8 *hopopt;
424         unsigned long interval;
425
426         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
427                                                  8 + sizeof(*mldq));
428         if (!skb)
429                 goto out;
430
431         skb->protocol = htons(ETH_P_IPV6);
432
433         /* Ethernet header */
434         skb_reset_mac_header(skb);
435         eth = eth_hdr(skb);
436
437         ether_addr_copy(eth->h_source, br->dev->dev_addr);
438         eth->h_proto = htons(ETH_P_IPV6);
439         skb_put(skb, sizeof(*eth));
440
441         /* IPv6 header + HbH option */
442         skb_set_network_header(skb, skb->len);
443         ip6h = ipv6_hdr(skb);
444
445         *(__force __be32 *)ip6h = htonl(0x60000000);
446         ip6h->payload_len = htons(8 + sizeof(*mldq));
447         ip6h->nexthdr = IPPROTO_HOPOPTS;
448         ip6h->hop_limit = 1;
449         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
450         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
451                                &ip6h->saddr)) {
452                 kfree_skb(skb);
453                 return NULL;
454         }
455         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
456
457         hopopt = (u8 *)(ip6h + 1);
458         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
459         hopopt[1] = 0;                          /* length of HbH */
460         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
461         hopopt[3] = 2;                          /* Length of RA Option */
462         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
463         hopopt[5] = 0;
464         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
465         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
466
467         skb_put(skb, sizeof(*ip6h) + 8);
468
469         /* ICMPv6 */
470         skb_set_transport_header(skb, skb->len);
471         mldq = (struct mld_msg *) icmp6_hdr(skb);
472
473         interval = ipv6_addr_any(group) ?
474                         br->multicast_query_response_interval :
475                         br->multicast_last_member_interval;
476
477         mldq->mld_type = ICMPV6_MGM_QUERY;
478         mldq->mld_code = 0;
479         mldq->mld_cksum = 0;
480         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
481         mldq->mld_reserved = 0;
482         mldq->mld_mca = *group;
483
484         /* checksum */
485         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
486                                           sizeof(*mldq), IPPROTO_ICMPV6,
487                                           csum_partial(mldq,
488                                                        sizeof(*mldq), 0));
489         skb_put(skb, sizeof(*mldq));
490
491         __skb_pull(skb, sizeof(*eth));
492
493 out:
494         return skb;
495 }
496 #endif
497
498 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
499                                                 struct br_ip *addr)
500 {
501         switch (addr->proto) {
502         case htons(ETH_P_IP):
503                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
504 #if IS_ENABLED(CONFIG_IPV6)
505         case htons(ETH_P_IPV6):
506                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
507 #endif
508         }
509         return NULL;
510 }
511
512 static struct net_bridge_mdb_entry *br_multicast_get_group(
513         struct net_bridge *br, struct net_bridge_port *port,
514         struct br_ip *group, int hash)
515 {
516         struct net_bridge_mdb_htable *mdb;
517         struct net_bridge_mdb_entry *mp;
518         unsigned int count = 0;
519         unsigned int max;
520         int elasticity;
521         int err;
522
523         mdb = rcu_dereference_protected(br->mdb, 1);
524         hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
525                 count++;
526                 if (unlikely(br_ip_equal(group, &mp->addr)))
527                         return mp;
528         }
529
530         elasticity = 0;
531         max = mdb->max;
532
533         if (unlikely(count > br->hash_elasticity && count)) {
534                 if (net_ratelimit())
535                         br_info(br, "Multicast hash table "
536                                 "chain limit reached: %s\n",
537                                 port ? port->dev->name : br->dev->name);
538
539                 elasticity = br->hash_elasticity;
540         }
541
542         if (mdb->size >= max) {
543                 max *= 2;
544                 if (unlikely(max > br->hash_max)) {
545                         br_warn(br, "Multicast hash table maximum of %d "
546                                 "reached, disabling snooping: %s\n",
547                                 br->hash_max,
548                                 port ? port->dev->name : br->dev->name);
549                         err = -E2BIG;
550 disable:
551                         br->multicast_disabled = 1;
552                         goto err;
553                 }
554         }
555
556         if (max > mdb->max || elasticity) {
557                 if (mdb->old) {
558                         if (net_ratelimit())
559                                 br_info(br, "Multicast hash table "
560                                         "on fire: %s\n",
561                                         port ? port->dev->name : br->dev->name);
562                         err = -EEXIST;
563                         goto err;
564                 }
565
566                 err = br_mdb_rehash(&br->mdb, max, elasticity);
567                 if (err) {
568                         br_warn(br, "Cannot rehash multicast "
569                                 "hash table, disabling snooping: %s, %d, %d\n",
570                                 port ? port->dev->name : br->dev->name,
571                                 mdb->size, err);
572                         goto disable;
573                 }
574
575                 err = -EAGAIN;
576                 goto err;
577         }
578
579         return NULL;
580
581 err:
582         mp = ERR_PTR(err);
583         return mp;
584 }
585
586 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
587         struct net_bridge_port *port, struct br_ip *group)
588 {
589         struct net_bridge_mdb_htable *mdb;
590         struct net_bridge_mdb_entry *mp;
591         int hash;
592         int err;
593
594         mdb = rcu_dereference_protected(br->mdb, 1);
595         if (!mdb) {
596                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
597                 if (err)
598                         return ERR_PTR(err);
599                 goto rehash;
600         }
601
602         hash = br_ip_hash(mdb, group);
603         mp = br_multicast_get_group(br, port, group, hash);
604         switch (PTR_ERR(mp)) {
605         case 0:
606                 break;
607
608         case -EAGAIN:
609 rehash:
610                 mdb = rcu_dereference_protected(br->mdb, 1);
611                 hash = br_ip_hash(mdb, group);
612                 break;
613
614         default:
615                 goto out;
616         }
617
618         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
619         if (unlikely(!mp))
620                 return ERR_PTR(-ENOMEM);
621
622         mp->br = br;
623         mp->addr = *group;
624         setup_timer(&mp->timer, br_multicast_group_expired,
625                     (unsigned long)mp);
626
627         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
628         mdb->size++;
629
630 out:
631         return mp;
632 }
633
634 struct net_bridge_port_group *br_multicast_new_port_group(
635                         struct net_bridge_port *port,
636                         struct br_ip *group,
637                         struct net_bridge_port_group __rcu *next,
638                         unsigned char state)
639 {
640         struct net_bridge_port_group *p;
641
642         p = kzalloc(sizeof(*p), GFP_ATOMIC);
643         if (unlikely(!p))
644                 return NULL;
645
646         p->addr = *group;
647         p->port = port;
648         p->state = state;
649         rcu_assign_pointer(p->next, next);
650         hlist_add_head(&p->mglist, &port->mglist);
651         setup_timer(&p->timer, br_multicast_port_group_expired,
652                     (unsigned long)p);
653         return p;
654 }
655
656 static int br_multicast_add_group(struct net_bridge *br,
657                                   struct net_bridge_port *port,
658                                   struct br_ip *group)
659 {
660         struct net_bridge_mdb_entry *mp;
661         struct net_bridge_port_group *p;
662         struct net_bridge_port_group __rcu **pp;
663         unsigned long now = jiffies;
664         int err;
665
666         spin_lock(&br->multicast_lock);
667         if (!netif_running(br->dev) ||
668             (port && port->state == BR_STATE_DISABLED))
669                 goto out;
670
671         mp = br_multicast_new_group(br, port, group);
672         err = PTR_ERR(mp);
673         if (IS_ERR(mp))
674                 goto err;
675
676         if (!port) {
677                 mp->mglist = true;
678                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
679                 goto out;
680         }
681
682         for (pp = &mp->ports;
683              (p = mlock_dereference(*pp, br)) != NULL;
684              pp = &p->next) {
685                 if (p->port == port)
686                         goto found;
687                 if ((unsigned long)p->port < (unsigned long)port)
688                         break;
689         }
690
691         p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
692         if (unlikely(!p))
693                 goto err;
694         rcu_assign_pointer(*pp, p);
695         br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
696
697 found:
698         mod_timer(&p->timer, now + br->multicast_membership_interval);
699 out:
700         err = 0;
701
702 err:
703         spin_unlock(&br->multicast_lock);
704         return err;
705 }
706
707 static int br_ip4_multicast_add_group(struct net_bridge *br,
708                                       struct net_bridge_port *port,
709                                       __be32 group,
710                                       __u16 vid)
711 {
712         struct br_ip br_group;
713
714         if (ipv4_is_local_multicast(group))
715                 return 0;
716
717         br_group.u.ip4 = group;
718         br_group.proto = htons(ETH_P_IP);
719         br_group.vid = vid;
720
721         return br_multicast_add_group(br, port, &br_group);
722 }
723
724 #if IS_ENABLED(CONFIG_IPV6)
725 static int br_ip6_multicast_add_group(struct net_bridge *br,
726                                       struct net_bridge_port *port,
727                                       const struct in6_addr *group,
728                                       __u16 vid)
729 {
730         struct br_ip br_group;
731
732         if (ipv6_addr_is_ll_all_nodes(group))
733                 return 0;
734
735         br_group.u.ip6 = *group;
736         br_group.proto = htons(ETH_P_IPV6);
737         br_group.vid = vid;
738
739         return br_multicast_add_group(br, port, &br_group);
740 }
741 #endif
742
743 static void br_multicast_router_expired(unsigned long data)
744 {
745         struct net_bridge_port *port = (void *)data;
746         struct net_bridge *br = port->br;
747
748         spin_lock(&br->multicast_lock);
749         if (port->multicast_router != 1 ||
750             timer_pending(&port->multicast_router_timer) ||
751             hlist_unhashed(&port->rlist))
752                 goto out;
753
754         hlist_del_init_rcu(&port->rlist);
755
756 out:
757         spin_unlock(&br->multicast_lock);
758 }
759
760 static void br_multicast_local_router_expired(unsigned long data)
761 {
762 }
763
764 static void br_multicast_querier_expired(struct net_bridge *br,
765                                          struct bridge_mcast_own_query *query)
766 {
767         spin_lock(&br->multicast_lock);
768         if (!netif_running(br->dev) || br->multicast_disabled)
769                 goto out;
770
771         br_multicast_start_querier(br, query);
772
773 out:
774         spin_unlock(&br->multicast_lock);
775 }
776
777 static void br_ip4_multicast_querier_expired(unsigned long data)
778 {
779         struct net_bridge *br = (void *)data;
780
781         br_multicast_querier_expired(br, &br->ip4_own_query);
782 }
783
784 #if IS_ENABLED(CONFIG_IPV6)
785 static void br_ip6_multicast_querier_expired(unsigned long data)
786 {
787         struct net_bridge *br = (void *)data;
788
789         br_multicast_querier_expired(br, &br->ip6_own_query);
790 }
791 #endif
792
793 static void br_multicast_select_own_querier(struct net_bridge *br,
794                                             struct br_ip *ip,
795                                             struct sk_buff *skb)
796 {
797         if (ip->proto == htons(ETH_P_IP))
798                 br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
799 #if IS_ENABLED(CONFIG_IPV6)
800         else
801                 br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
802 #endif
803 }
804
805 static void __br_multicast_send_query(struct net_bridge *br,
806                                       struct net_bridge_port *port,
807                                       struct br_ip *ip)
808 {
809         struct sk_buff *skb;
810
811         skb = br_multicast_alloc_query(br, ip);
812         if (!skb)
813                 return;
814
815         if (port) {
816                 skb->dev = port->dev;
817                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
818                         br_dev_queue_push_xmit);
819         } else {
820                 br_multicast_select_own_querier(br, ip, skb);
821                 netif_rx(skb);
822         }
823 }
824
825 static void br_multicast_send_query(struct net_bridge *br,
826                                     struct net_bridge_port *port,
827                                     struct bridge_mcast_own_query *own_query)
828 {
829         unsigned long time;
830         struct br_ip br_group;
831         struct bridge_mcast_other_query *other_query = NULL;
832
833         if (!netif_running(br->dev) || br->multicast_disabled ||
834             !br->multicast_querier)
835                 return;
836
837         memset(&br_group.u, 0, sizeof(br_group.u));
838
839         if (port ? (own_query == &port->ip4_own_query) :
840                    (own_query == &br->ip4_own_query)) {
841                 other_query = &br->ip4_other_query;
842                 br_group.proto = htons(ETH_P_IP);
843 #if IS_ENABLED(CONFIG_IPV6)
844         } else {
845                 other_query = &br->ip6_other_query;
846                 br_group.proto = htons(ETH_P_IPV6);
847 #endif
848         }
849
850         if (!other_query || timer_pending(&other_query->timer))
851                 return;
852
853         __br_multicast_send_query(br, port, &br_group);
854
855         time = jiffies;
856         time += own_query->startup_sent < br->multicast_startup_query_count ?
857                 br->multicast_startup_query_interval :
858                 br->multicast_query_interval;
859         mod_timer(&own_query->timer, time);
860 }
861
862 static void
863 br_multicast_port_query_expired(struct net_bridge_port *port,
864                                 struct bridge_mcast_own_query *query)
865 {
866         struct net_bridge *br = port->br;
867
868         spin_lock(&br->multicast_lock);
869         if (port->state == BR_STATE_DISABLED ||
870             port->state == BR_STATE_BLOCKING)
871                 goto out;
872
873         if (query->startup_sent < br->multicast_startup_query_count)
874                 query->startup_sent++;
875
876         br_multicast_send_query(port->br, port, query);
877
878 out:
879         spin_unlock(&br->multicast_lock);
880 }
881
882 static void br_ip4_multicast_port_query_expired(unsigned long data)
883 {
884         struct net_bridge_port *port = (void *)data;
885
886         br_multicast_port_query_expired(port, &port->ip4_own_query);
887 }
888
889 #if IS_ENABLED(CONFIG_IPV6)
890 static void br_ip6_multicast_port_query_expired(unsigned long data)
891 {
892         struct net_bridge_port *port = (void *)data;
893
894         br_multicast_port_query_expired(port, &port->ip6_own_query);
895 }
896 #endif
897
898 void br_multicast_add_port(struct net_bridge_port *port)
899 {
900         port->multicast_router = 1;
901
902         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
903                     (unsigned long)port);
904         setup_timer(&port->ip4_own_query.timer,
905                     br_ip4_multicast_port_query_expired, (unsigned long)port);
906 #if IS_ENABLED(CONFIG_IPV6)
907         setup_timer(&port->ip6_own_query.timer,
908                     br_ip6_multicast_port_query_expired, (unsigned long)port);
909 #endif
910 }
911
912 void br_multicast_del_port(struct net_bridge_port *port)
913 {
914         del_timer_sync(&port->multicast_router_timer);
915 }
916
917 static void br_multicast_enable(struct bridge_mcast_own_query *query)
918 {
919         query->startup_sent = 0;
920
921         if (try_to_del_timer_sync(&query->timer) >= 0 ||
922             del_timer(&query->timer))
923                 mod_timer(&query->timer, jiffies);
924 }
925
926 void br_multicast_enable_port(struct net_bridge_port *port)
927 {
928         struct net_bridge *br = port->br;
929
930         spin_lock(&br->multicast_lock);
931         if (br->multicast_disabled || !netif_running(br->dev))
932                 goto out;
933
934         br_multicast_enable(&port->ip4_own_query);
935 #if IS_ENABLED(CONFIG_IPV6)
936         br_multicast_enable(&port->ip6_own_query);
937 #endif
938
939 out:
940         spin_unlock(&br->multicast_lock);
941 }
942
943 void br_multicast_disable_port(struct net_bridge_port *port)
944 {
945         struct net_bridge *br = port->br;
946         struct net_bridge_port_group *pg;
947         struct hlist_node *n;
948
949         spin_lock(&br->multicast_lock);
950         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
951                 br_multicast_del_pg(br, pg);
952
953         if (!hlist_unhashed(&port->rlist))
954                 hlist_del_init_rcu(&port->rlist);
955         del_timer(&port->multicast_router_timer);
956         del_timer(&port->ip4_own_query.timer);
957 #if IS_ENABLED(CONFIG_IPV6)
958         del_timer(&port->ip6_own_query.timer);
959 #endif
960         spin_unlock(&br->multicast_lock);
961 }
962
963 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
964                                          struct net_bridge_port *port,
965                                          struct sk_buff *skb,
966                                          u16 vid)
967 {
968         struct igmpv3_report *ih;
969         struct igmpv3_grec *grec;
970         int i;
971         int len;
972         int num;
973         int type;
974         int err = 0;
975         __be32 group;
976
977         if (!pskb_may_pull(skb, sizeof(*ih)))
978                 return -EINVAL;
979
980         ih = igmpv3_report_hdr(skb);
981         num = ntohs(ih->ngrec);
982         len = sizeof(*ih);
983
984         for (i = 0; i < num; i++) {
985                 len += sizeof(*grec);
986                 if (!pskb_may_pull(skb, len))
987                         return -EINVAL;
988
989                 grec = (void *)(skb->data + len - sizeof(*grec));
990                 group = grec->grec_mca;
991                 type = grec->grec_type;
992
993                 len += ntohs(grec->grec_nsrcs) * 4;
994                 if (!pskb_may_pull(skb, len))
995                         return -EINVAL;
996
997                 /* We treat this as an IGMPv2 report for now. */
998                 switch (type) {
999                 case IGMPV3_MODE_IS_INCLUDE:
1000                 case IGMPV3_MODE_IS_EXCLUDE:
1001                 case IGMPV3_CHANGE_TO_INCLUDE:
1002                 case IGMPV3_CHANGE_TO_EXCLUDE:
1003                 case IGMPV3_ALLOW_NEW_SOURCES:
1004                 case IGMPV3_BLOCK_OLD_SOURCES:
1005                         break;
1006
1007                 default:
1008                         continue;
1009                 }
1010
1011                 err = br_ip4_multicast_add_group(br, port, group, vid);
1012                 if (err)
1013                         break;
1014         }
1015
1016         return err;
1017 }
1018
1019 #if IS_ENABLED(CONFIG_IPV6)
1020 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1021                                         struct net_bridge_port *port,
1022                                         struct sk_buff *skb,
1023                                         u16 vid)
1024 {
1025         struct icmp6hdr *icmp6h;
1026         struct mld2_grec *grec;
1027         int i;
1028         int len;
1029         int num;
1030         int err = 0;
1031
1032         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1033                 return -EINVAL;
1034
1035         icmp6h = icmp6_hdr(skb);
1036         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1037         len = sizeof(*icmp6h);
1038
1039         for (i = 0; i < num; i++) {
1040                 __be16 *nsrcs, _nsrcs;
1041
1042                 nsrcs = skb_header_pointer(skb,
1043                                            len + offsetof(struct mld2_grec,
1044                                                           grec_nsrcs),
1045                                            sizeof(_nsrcs), &_nsrcs);
1046                 if (!nsrcs)
1047                         return -EINVAL;
1048
1049                 if (!pskb_may_pull(skb,
1050                                    len + sizeof(*grec) +
1051                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1052                         return -EINVAL;
1053
1054                 grec = (struct mld2_grec *)(skb->data + len);
1055                 len += sizeof(*grec) +
1056                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1057
1058                 /* We treat these as MLDv1 reports for now. */
1059                 switch (grec->grec_type) {
1060                 case MLD2_MODE_IS_INCLUDE:
1061                 case MLD2_MODE_IS_EXCLUDE:
1062                 case MLD2_CHANGE_TO_INCLUDE:
1063                 case MLD2_CHANGE_TO_EXCLUDE:
1064                 case MLD2_ALLOW_NEW_SOURCES:
1065                 case MLD2_BLOCK_OLD_SOURCES:
1066                         break;
1067
1068                 default:
1069                         continue;
1070                 }
1071
1072                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1073                                                  vid);
1074                 if (!err)
1075                         break;
1076         }
1077
1078         return err;
1079 }
1080 #endif
1081
1082 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1083                                             struct net_bridge_port *port,
1084                                             __be32 saddr)
1085 {
1086         if (!timer_pending(&br->ip4_own_query.timer) &&
1087             !timer_pending(&br->ip4_other_query.timer))
1088                 goto update;
1089
1090         if (!br->ip4_querier.addr.u.ip4)
1091                 goto update;
1092
1093         if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1094                 goto update;
1095
1096         return false;
1097
1098 update:
1099         br->ip4_querier.addr.u.ip4 = saddr;
1100
1101         /* update protected by general multicast_lock by caller */
1102         rcu_assign_pointer(br->ip4_querier.port, port);
1103
1104         return true;
1105 }
1106
1107 #if IS_ENABLED(CONFIG_IPV6)
1108 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1109                                             struct net_bridge_port *port,
1110                                             struct in6_addr *saddr)
1111 {
1112         if (!timer_pending(&br->ip6_own_query.timer) &&
1113             !timer_pending(&br->ip6_other_query.timer))
1114                 goto update;
1115
1116         if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1117                 goto update;
1118
1119         return false;
1120
1121 update:
1122         br->ip6_querier.addr.u.ip6 = *saddr;
1123
1124         /* update protected by general multicast_lock by caller */
1125         rcu_assign_pointer(br->ip6_querier.port, port);
1126
1127         return true;
1128 }
1129 #endif
1130
1131 static bool br_multicast_select_querier(struct net_bridge *br,
1132                                         struct net_bridge_port *port,
1133                                         struct br_ip *saddr)
1134 {
1135         switch (saddr->proto) {
1136         case htons(ETH_P_IP):
1137                 return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1138 #if IS_ENABLED(CONFIG_IPV6)
1139         case htons(ETH_P_IPV6):
1140                 return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1141 #endif
1142         }
1143
1144         return false;
1145 }
1146
1147 static void
1148 br_multicast_update_query_timer(struct net_bridge *br,
1149                                 struct bridge_mcast_other_query *query,
1150                                 unsigned long max_delay)
1151 {
1152         if (!timer_pending(&query->timer))
1153                 query->delay_time = jiffies + max_delay;
1154
1155         mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1156 }
1157
1158 /*
1159  * Add port to router_list
1160  *  list is maintained ordered by pointer value
1161  *  and locked by br->multicast_lock and RCU
1162  */
1163 static void br_multicast_add_router(struct net_bridge *br,
1164                                     struct net_bridge_port *port)
1165 {
1166         struct net_bridge_port *p;
1167         struct hlist_node *slot = NULL;
1168
1169         hlist_for_each_entry(p, &br->router_list, rlist) {
1170                 if ((unsigned long) port >= (unsigned long) p)
1171                         break;
1172                 slot = &p->rlist;
1173         }
1174
1175         if (slot)
1176                 hlist_add_behind_rcu(&port->rlist, slot);
1177         else
1178                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1179 }
1180
1181 static void br_multicast_mark_router(struct net_bridge *br,
1182                                      struct net_bridge_port *port)
1183 {
1184         unsigned long now = jiffies;
1185
1186         if (!port) {
1187                 if (br->multicast_router == 1)
1188                         mod_timer(&br->multicast_router_timer,
1189                                   now + br->multicast_querier_interval);
1190                 return;
1191         }
1192
1193         if (port->multicast_router != 1)
1194                 return;
1195
1196         if (!hlist_unhashed(&port->rlist))
1197                 goto timer;
1198
1199         br_multicast_add_router(br, port);
1200
1201 timer:
1202         mod_timer(&port->multicast_router_timer,
1203                   now + br->multicast_querier_interval);
1204 }
1205
1206 static void br_multicast_query_received(struct net_bridge *br,
1207                                         struct net_bridge_port *port,
1208                                         struct bridge_mcast_other_query *query,
1209                                         struct br_ip *saddr,
1210                                         unsigned long max_delay)
1211 {
1212         if (!br_multicast_select_querier(br, port, saddr))
1213                 return;
1214
1215         br_multicast_update_query_timer(br, query, max_delay);
1216         br_multicast_mark_router(br, port);
1217 }
1218
1219 static int br_ip4_multicast_query(struct net_bridge *br,
1220                                   struct net_bridge_port *port,
1221                                   struct sk_buff *skb,
1222                                   u16 vid)
1223 {
1224         const struct iphdr *iph = ip_hdr(skb);
1225         struct igmphdr *ih = igmp_hdr(skb);
1226         struct net_bridge_mdb_entry *mp;
1227         struct igmpv3_query *ih3;
1228         struct net_bridge_port_group *p;
1229         struct net_bridge_port_group __rcu **pp;
1230         struct br_ip saddr;
1231         unsigned long max_delay;
1232         unsigned long now = jiffies;
1233         __be32 group;
1234         int err = 0;
1235
1236         spin_lock(&br->multicast_lock);
1237         if (!netif_running(br->dev) ||
1238             (port && port->state == BR_STATE_DISABLED))
1239                 goto out;
1240
1241         group = ih->group;
1242
1243         if (skb->len == sizeof(*ih)) {
1244                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1245
1246                 if (!max_delay) {
1247                         max_delay = 10 * HZ;
1248                         group = 0;
1249                 }
1250         } else {
1251                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1252                         err = -EINVAL;
1253                         goto out;
1254                 }
1255
1256                 ih3 = igmpv3_query_hdr(skb);
1257                 if (ih3->nsrcs)
1258                         goto out;
1259
1260                 max_delay = ih3->code ?
1261                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1262         }
1263
1264         /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1265          * all-systems destination addresses (224.0.0.1) for general queries
1266          */
1267         if (!group && iph->daddr != htonl(INADDR_ALLHOSTS_GROUP)) {
1268                 err = -EINVAL;
1269                 goto out;
1270         }
1271
1272         if (!group) {
1273                 saddr.proto = htons(ETH_P_IP);
1274                 saddr.u.ip4 = iph->saddr;
1275
1276                 br_multicast_query_received(br, port, &br->ip4_other_query,
1277                                             &saddr, max_delay);
1278                 goto out;
1279         }
1280
1281         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1282         if (!mp)
1283                 goto out;
1284
1285         max_delay *= br->multicast_last_member_count;
1286
1287         if (mp->mglist &&
1288             (timer_pending(&mp->timer) ?
1289              time_after(mp->timer.expires, now + max_delay) :
1290              try_to_del_timer_sync(&mp->timer) >= 0))
1291                 mod_timer(&mp->timer, now + max_delay);
1292
1293         for (pp = &mp->ports;
1294              (p = mlock_dereference(*pp, br)) != NULL;
1295              pp = &p->next) {
1296                 if (timer_pending(&p->timer) ?
1297                     time_after(p->timer.expires, now + max_delay) :
1298                     try_to_del_timer_sync(&p->timer) >= 0)
1299                         mod_timer(&p->timer, now + max_delay);
1300         }
1301
1302 out:
1303         spin_unlock(&br->multicast_lock);
1304         return err;
1305 }
1306
1307 #if IS_ENABLED(CONFIG_IPV6)
1308 static int br_ip6_multicast_query(struct net_bridge *br,
1309                                   struct net_bridge_port *port,
1310                                   struct sk_buff *skb,
1311                                   u16 vid)
1312 {
1313         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1314         struct mld_msg *mld;
1315         struct net_bridge_mdb_entry *mp;
1316         struct mld2_query *mld2q;
1317         struct net_bridge_port_group *p;
1318         struct net_bridge_port_group __rcu **pp;
1319         struct br_ip saddr;
1320         unsigned long max_delay;
1321         unsigned long now = jiffies;
1322         const struct in6_addr *group = NULL;
1323         bool is_general_query;
1324         int err = 0;
1325
1326         spin_lock(&br->multicast_lock);
1327         if (!netif_running(br->dev) ||
1328             (port && port->state == BR_STATE_DISABLED))
1329                 goto out;
1330
1331         /* RFC2710+RFC3810 (MLDv1+MLDv2) require link-local source addresses */
1332         if (!(ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1333                 err = -EINVAL;
1334                 goto out;
1335         }
1336
1337         if (skb->len == sizeof(*mld)) {
1338                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1339                         err = -EINVAL;
1340                         goto out;
1341                 }
1342                 mld = (struct mld_msg *) icmp6_hdr(skb);
1343                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1344                 if (max_delay)
1345                         group = &mld->mld_mca;
1346         } else {
1347                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1348                         err = -EINVAL;
1349                         goto out;
1350                 }
1351                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1352                 if (!mld2q->mld2q_nsrcs)
1353                         group = &mld2q->mld2q_mca;
1354
1355                 max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1356         }
1357
1358         is_general_query = group && ipv6_addr_any(group);
1359
1360         /* RFC2710+RFC3810 (MLDv1+MLDv2) require the multicast link layer
1361          * all-nodes destination address (ff02::1) for general queries
1362          */
1363         if (is_general_query && !ipv6_addr_is_ll_all_nodes(&ip6h->daddr)) {
1364                 err = -EINVAL;
1365                 goto out;
1366         }
1367
1368         if (is_general_query) {
1369                 saddr.proto = htons(ETH_P_IPV6);
1370                 saddr.u.ip6 = ip6h->saddr;
1371
1372                 br_multicast_query_received(br, port, &br->ip6_other_query,
1373                                             &saddr, max_delay);
1374                 goto out;
1375         } else if (!group) {
1376                 goto out;
1377         }
1378
1379         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1380         if (!mp)
1381                 goto out;
1382
1383         max_delay *= br->multicast_last_member_count;
1384         if (mp->mglist &&
1385             (timer_pending(&mp->timer) ?
1386              time_after(mp->timer.expires, now + max_delay) :
1387              try_to_del_timer_sync(&mp->timer) >= 0))
1388                 mod_timer(&mp->timer, now + max_delay);
1389
1390         for (pp = &mp->ports;
1391              (p = mlock_dereference(*pp, br)) != NULL;
1392              pp = &p->next) {
1393                 if (timer_pending(&p->timer) ?
1394                     time_after(p->timer.expires, now + max_delay) :
1395                     try_to_del_timer_sync(&p->timer) >= 0)
1396                         mod_timer(&p->timer, now + max_delay);
1397         }
1398
1399 out:
1400         spin_unlock(&br->multicast_lock);
1401         return err;
1402 }
1403 #endif
1404
1405 static void
1406 br_multicast_leave_group(struct net_bridge *br,
1407                          struct net_bridge_port *port,
1408                          struct br_ip *group,
1409                          struct bridge_mcast_other_query *other_query,
1410                          struct bridge_mcast_own_query *own_query)
1411 {
1412         struct net_bridge_mdb_htable *mdb;
1413         struct net_bridge_mdb_entry *mp;
1414         struct net_bridge_port_group *p;
1415         unsigned long now;
1416         unsigned long time;
1417
1418         spin_lock(&br->multicast_lock);
1419         if (!netif_running(br->dev) ||
1420             (port && port->state == BR_STATE_DISABLED) ||
1421             timer_pending(&other_query->timer))
1422                 goto out;
1423
1424         mdb = mlock_dereference(br->mdb, br);
1425         mp = br_mdb_ip_get(mdb, group);
1426         if (!mp)
1427                 goto out;
1428
1429         if (br->multicast_querier) {
1430                 __br_multicast_send_query(br, port, &mp->addr);
1431
1432                 time = jiffies + br->multicast_last_member_count *
1433                                  br->multicast_last_member_interval;
1434
1435                 mod_timer(&own_query->timer, time);
1436
1437                 for (p = mlock_dereference(mp->ports, br);
1438                      p != NULL;
1439                      p = mlock_dereference(p->next, br)) {
1440                         if (p->port != port)
1441                                 continue;
1442
1443                         if (!hlist_unhashed(&p->mglist) &&
1444                             (timer_pending(&p->timer) ?
1445                              time_after(p->timer.expires, time) :
1446                              try_to_del_timer_sync(&p->timer) >= 0)) {
1447                                 mod_timer(&p->timer, time);
1448                         }
1449
1450                         break;
1451                 }
1452         }
1453
1454         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1455                 struct net_bridge_port_group __rcu **pp;
1456
1457                 for (pp = &mp->ports;
1458                      (p = mlock_dereference(*pp, br)) != NULL;
1459                      pp = &p->next) {
1460                         if (p->port != port)
1461                                 continue;
1462
1463                         rcu_assign_pointer(*pp, p->next);
1464                         hlist_del_init(&p->mglist);
1465                         del_timer(&p->timer);
1466                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1467                         br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1468
1469                         if (!mp->ports && !mp->mglist &&
1470                             netif_running(br->dev))
1471                                 mod_timer(&mp->timer, jiffies);
1472                 }
1473                 goto out;
1474         }
1475
1476         now = jiffies;
1477         time = now + br->multicast_last_member_count *
1478                      br->multicast_last_member_interval;
1479
1480         if (!port) {
1481                 if (mp->mglist &&
1482                     (timer_pending(&mp->timer) ?
1483                      time_after(mp->timer.expires, time) :
1484                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1485                         mod_timer(&mp->timer, time);
1486                 }
1487
1488                 goto out;
1489         }
1490
1491         for (p = mlock_dereference(mp->ports, br);
1492              p != NULL;
1493              p = mlock_dereference(p->next, br)) {
1494                 if (p->port != port)
1495                         continue;
1496
1497                 if (!hlist_unhashed(&p->mglist) &&
1498                     (timer_pending(&p->timer) ?
1499                      time_after(p->timer.expires, time) :
1500                      try_to_del_timer_sync(&p->timer) >= 0)) {
1501                         mod_timer(&p->timer, time);
1502                 }
1503
1504                 break;
1505         }
1506 out:
1507         spin_unlock(&br->multicast_lock);
1508 }
1509
1510 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1511                                          struct net_bridge_port *port,
1512                                          __be32 group,
1513                                          __u16 vid)
1514 {
1515         struct br_ip br_group;
1516         struct bridge_mcast_own_query *own_query;
1517
1518         if (ipv4_is_local_multicast(group))
1519                 return;
1520
1521         own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1522
1523         br_group.u.ip4 = group;
1524         br_group.proto = htons(ETH_P_IP);
1525         br_group.vid = vid;
1526
1527         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1528                                  own_query);
1529 }
1530
1531 #if IS_ENABLED(CONFIG_IPV6)
1532 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1533                                          struct net_bridge_port *port,
1534                                          const struct in6_addr *group,
1535                                          __u16 vid)
1536 {
1537         struct br_ip br_group;
1538         struct bridge_mcast_own_query *own_query;
1539
1540         if (ipv6_addr_is_ll_all_nodes(group))
1541                 return;
1542
1543         own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1544
1545         br_group.u.ip6 = *group;
1546         br_group.proto = htons(ETH_P_IPV6);
1547         br_group.vid = vid;
1548
1549         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1550                                  own_query);
1551 }
1552 #endif
1553
1554 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1555                                  struct net_bridge_port *port,
1556                                  struct sk_buff *skb,
1557                                  u16 vid)
1558 {
1559         struct sk_buff *skb2 = skb;
1560         const struct iphdr *iph;
1561         struct igmphdr *ih;
1562         unsigned int len;
1563         unsigned int offset;
1564         int err;
1565
1566         /* We treat OOM as packet loss for now. */
1567         if (!pskb_may_pull(skb, sizeof(*iph)))
1568                 return -EINVAL;
1569
1570         iph = ip_hdr(skb);
1571
1572         if (iph->ihl < 5 || iph->version != 4)
1573                 return -EINVAL;
1574
1575         if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1576                 return -EINVAL;
1577
1578         iph = ip_hdr(skb);
1579
1580         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1581                 return -EINVAL;
1582
1583         if (iph->protocol != IPPROTO_IGMP) {
1584                 if (!ipv4_is_local_multicast(iph->daddr))
1585                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1586                 return 0;
1587         }
1588
1589         len = ntohs(iph->tot_len);
1590         if (skb->len < len || len < ip_hdrlen(skb))
1591                 return -EINVAL;
1592
1593         if (skb->len > len) {
1594                 skb2 = skb_clone(skb, GFP_ATOMIC);
1595                 if (!skb2)
1596                         return -ENOMEM;
1597
1598                 err = pskb_trim_rcsum(skb2, len);
1599                 if (err)
1600                         goto err_out;
1601         }
1602
1603         len -= ip_hdrlen(skb2);
1604         offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1605         __skb_pull(skb2, offset);
1606         skb_reset_transport_header(skb2);
1607
1608         err = -EINVAL;
1609         if (!pskb_may_pull(skb2, sizeof(*ih)))
1610                 goto out;
1611
1612         switch (skb2->ip_summed) {
1613         case CHECKSUM_COMPLETE:
1614                 if (!csum_fold(skb2->csum))
1615                         break;
1616                 /* fall through */
1617         case CHECKSUM_NONE:
1618                 skb2->csum = 0;
1619                 if (skb_checksum_complete(skb2))
1620                         goto out;
1621         }
1622
1623         err = 0;
1624
1625         BR_INPUT_SKB_CB(skb)->igmp = 1;
1626         ih = igmp_hdr(skb2);
1627
1628         switch (ih->type) {
1629         case IGMP_HOST_MEMBERSHIP_REPORT:
1630         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1631                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1632                 err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1633                 break;
1634         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1635                 err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
1636                 break;
1637         case IGMP_HOST_MEMBERSHIP_QUERY:
1638                 err = br_ip4_multicast_query(br, port, skb2, vid);
1639                 break;
1640         case IGMP_HOST_LEAVE_MESSAGE:
1641                 br_ip4_multicast_leave_group(br, port, ih->group, vid);
1642                 break;
1643         }
1644
1645 out:
1646         __skb_push(skb2, offset);
1647 err_out:
1648         if (skb2 != skb)
1649                 kfree_skb(skb2);
1650         return err;
1651 }
1652
1653 #if IS_ENABLED(CONFIG_IPV6)
1654 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1655                                  struct net_bridge_port *port,
1656                                  struct sk_buff *skb,
1657                                  u16 vid)
1658 {
1659         struct sk_buff *skb2;
1660         const struct ipv6hdr *ip6h;
1661         u8 icmp6_type;
1662         u8 nexthdr;
1663         __be16 frag_off;
1664         unsigned int len;
1665         int offset;
1666         int err;
1667
1668         if (!pskb_may_pull(skb, sizeof(*ip6h)))
1669                 return -EINVAL;
1670
1671         ip6h = ipv6_hdr(skb);
1672
1673         /*
1674          * We're interested in MLD messages only.
1675          *  - Version is 6
1676          *  - MLD has always Router Alert hop-by-hop option
1677          *  - But we do not support jumbrograms.
1678          */
1679         if (ip6h->version != 6)
1680                 return 0;
1681
1682         /* Prevent flooding this packet if there is no listener present */
1683         if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
1684                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1685
1686         if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
1687             ip6h->payload_len == 0)
1688                 return 0;
1689
1690         len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1691         if (skb->len < len)
1692                 return -EINVAL;
1693
1694         nexthdr = ip6h->nexthdr;
1695         offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1696
1697         if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1698                 return 0;
1699
1700         /* Okay, we found ICMPv6 header */
1701         skb2 = skb_clone(skb, GFP_ATOMIC);
1702         if (!skb2)
1703                 return -ENOMEM;
1704
1705         err = -EINVAL;
1706         if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1707                 goto out;
1708
1709         len -= offset - skb_network_offset(skb2);
1710
1711         __skb_pull(skb2, offset);
1712         skb_reset_transport_header(skb2);
1713         skb_postpull_rcsum(skb2, skb_network_header(skb2),
1714                            skb_network_header_len(skb2));
1715
1716         icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1717
1718         switch (icmp6_type) {
1719         case ICMPV6_MGM_QUERY:
1720         case ICMPV6_MGM_REPORT:
1721         case ICMPV6_MGM_REDUCTION:
1722         case ICMPV6_MLD2_REPORT:
1723                 break;
1724         default:
1725                 err = 0;
1726                 goto out;
1727         }
1728
1729         /* Okay, we found MLD message. Check further. */
1730         if (skb2->len > len) {
1731                 err = pskb_trim_rcsum(skb2, len);
1732                 if (err)
1733                         goto out;
1734                 err = -EINVAL;
1735         }
1736
1737         ip6h = ipv6_hdr(skb2);
1738
1739         switch (skb2->ip_summed) {
1740         case CHECKSUM_COMPLETE:
1741                 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1742                                         IPPROTO_ICMPV6, skb2->csum))
1743                         break;
1744                 /*FALLTHROUGH*/
1745         case CHECKSUM_NONE:
1746                 skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1747                                                         &ip6h->daddr,
1748                                                         skb2->len,
1749                                                         IPPROTO_ICMPV6, 0));
1750                 if (__skb_checksum_complete(skb2))
1751                         goto out;
1752         }
1753
1754         err = 0;
1755
1756         BR_INPUT_SKB_CB(skb)->igmp = 1;
1757
1758         switch (icmp6_type) {
1759         case ICMPV6_MGM_REPORT:
1760             {
1761                 struct mld_msg *mld;
1762                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1763                         err = -EINVAL;
1764                         goto out;
1765                 }
1766                 mld = (struct mld_msg *)skb_transport_header(skb2);
1767                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1768                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1769                 break;
1770             }
1771         case ICMPV6_MLD2_REPORT:
1772                 err = br_ip6_multicast_mld2_report(br, port, skb2, vid);
1773                 break;
1774         case ICMPV6_MGM_QUERY:
1775                 err = br_ip6_multicast_query(br, port, skb2, vid);
1776                 break;
1777         case ICMPV6_MGM_REDUCTION:
1778             {
1779                 struct mld_msg *mld;
1780                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1781                         err = -EINVAL;
1782                         goto out;
1783                 }
1784                 mld = (struct mld_msg *)skb_transport_header(skb2);
1785                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1786             }
1787         }
1788
1789 out:
1790         kfree_skb(skb2);
1791         return err;
1792 }
1793 #endif
1794
1795 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1796                      struct sk_buff *skb, u16 vid)
1797 {
1798         BR_INPUT_SKB_CB(skb)->igmp = 0;
1799         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1800
1801         if (br->multicast_disabled)
1802                 return 0;
1803
1804         switch (skb->protocol) {
1805         case htons(ETH_P_IP):
1806                 return br_multicast_ipv4_rcv(br, port, skb, vid);
1807 #if IS_ENABLED(CONFIG_IPV6)
1808         case htons(ETH_P_IPV6):
1809                 return br_multicast_ipv6_rcv(br, port, skb, vid);
1810 #endif
1811         }
1812
1813         return 0;
1814 }
1815
1816 static void br_multicast_query_expired(struct net_bridge *br,
1817                                        struct bridge_mcast_own_query *query,
1818                                        struct bridge_mcast_querier *querier)
1819 {
1820         spin_lock(&br->multicast_lock);
1821         if (query->startup_sent < br->multicast_startup_query_count)
1822                 query->startup_sent++;
1823
1824         RCU_INIT_POINTER(querier, NULL);
1825         br_multicast_send_query(br, NULL, query);
1826         spin_unlock(&br->multicast_lock);
1827 }
1828
1829 static void br_ip4_multicast_query_expired(unsigned long data)
1830 {
1831         struct net_bridge *br = (void *)data;
1832
1833         br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1834 }
1835
1836 #if IS_ENABLED(CONFIG_IPV6)
1837 static void br_ip6_multicast_query_expired(unsigned long data)
1838 {
1839         struct net_bridge *br = (void *)data;
1840
1841         br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1842 }
1843 #endif
1844
1845 void br_multicast_init(struct net_bridge *br)
1846 {
1847         br->hash_elasticity = 4;
1848         br->hash_max = 512;
1849
1850         br->multicast_router = 1;
1851         br->multicast_querier = 0;
1852         br->multicast_query_use_ifaddr = 0;
1853         br->multicast_last_member_count = 2;
1854         br->multicast_startup_query_count = 2;
1855
1856         br->multicast_last_member_interval = HZ;
1857         br->multicast_query_response_interval = 10 * HZ;
1858         br->multicast_startup_query_interval = 125 * HZ / 4;
1859         br->multicast_query_interval = 125 * HZ;
1860         br->multicast_querier_interval = 255 * HZ;
1861         br->multicast_membership_interval = 260 * HZ;
1862
1863         br->ip4_other_query.delay_time = 0;
1864         br->ip4_querier.port = NULL;
1865 #if IS_ENABLED(CONFIG_IPV6)
1866         br->ip6_other_query.delay_time = 0;
1867         br->ip6_querier.port = NULL;
1868 #endif
1869
1870         spin_lock_init(&br->multicast_lock);
1871         setup_timer(&br->multicast_router_timer,
1872                     br_multicast_local_router_expired, 0);
1873         setup_timer(&br->ip4_other_query.timer,
1874                     br_ip4_multicast_querier_expired, (unsigned long)br);
1875         setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1876                     (unsigned long)br);
1877 #if IS_ENABLED(CONFIG_IPV6)
1878         setup_timer(&br->ip6_other_query.timer,
1879                     br_ip6_multicast_querier_expired, (unsigned long)br);
1880         setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1881                     (unsigned long)br);
1882 #endif
1883 }
1884
1885 static void __br_multicast_open(struct net_bridge *br,
1886                                 struct bridge_mcast_own_query *query)
1887 {
1888         query->startup_sent = 0;
1889
1890         if (br->multicast_disabled)
1891                 return;
1892
1893         mod_timer(&query->timer, jiffies);
1894 }
1895
1896 void br_multicast_open(struct net_bridge *br)
1897 {
1898         __br_multicast_open(br, &br->ip4_own_query);
1899 #if IS_ENABLED(CONFIG_IPV6)
1900         __br_multicast_open(br, &br->ip6_own_query);
1901 #endif
1902 }
1903
1904 void br_multicast_stop(struct net_bridge *br)
1905 {
1906         struct net_bridge_mdb_htable *mdb;
1907         struct net_bridge_mdb_entry *mp;
1908         struct hlist_node *n;
1909         u32 ver;
1910         int i;
1911
1912         del_timer_sync(&br->multicast_router_timer);
1913         del_timer_sync(&br->ip4_other_query.timer);
1914         del_timer_sync(&br->ip4_own_query.timer);
1915 #if IS_ENABLED(CONFIG_IPV6)
1916         del_timer_sync(&br->ip6_other_query.timer);
1917         del_timer_sync(&br->ip6_own_query.timer);
1918 #endif
1919
1920         spin_lock_bh(&br->multicast_lock);
1921         mdb = mlock_dereference(br->mdb, br);
1922         if (!mdb)
1923                 goto out;
1924
1925         br->mdb = NULL;
1926
1927         ver = mdb->ver;
1928         for (i = 0; i < mdb->max; i++) {
1929                 hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1930                                           hlist[ver]) {
1931                         del_timer(&mp->timer);
1932                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1933                 }
1934         }
1935
1936         if (mdb->old) {
1937                 spin_unlock_bh(&br->multicast_lock);
1938                 rcu_barrier_bh();
1939                 spin_lock_bh(&br->multicast_lock);
1940                 WARN_ON(mdb->old);
1941         }
1942
1943         mdb->old = mdb;
1944         call_rcu_bh(&mdb->rcu, br_mdb_free);
1945
1946 out:
1947         spin_unlock_bh(&br->multicast_lock);
1948 }
1949
1950 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1951 {
1952         int err = -ENOENT;
1953
1954         spin_lock_bh(&br->multicast_lock);
1955         if (!netif_running(br->dev))
1956                 goto unlock;
1957
1958         switch (val) {
1959         case 0:
1960         case 2:
1961                 del_timer(&br->multicast_router_timer);
1962                 /* fall through */
1963         case 1:
1964                 br->multicast_router = val;
1965                 err = 0;
1966                 break;
1967
1968         default:
1969                 err = -EINVAL;
1970                 break;
1971         }
1972
1973 unlock:
1974         spin_unlock_bh(&br->multicast_lock);
1975
1976         return err;
1977 }
1978
1979 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1980 {
1981         struct net_bridge *br = p->br;
1982         int err = -ENOENT;
1983
1984         spin_lock(&br->multicast_lock);
1985         if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1986                 goto unlock;
1987
1988         switch (val) {
1989         case 0:
1990         case 1:
1991         case 2:
1992                 p->multicast_router = val;
1993                 err = 0;
1994
1995                 if (val < 2 && !hlist_unhashed(&p->rlist))
1996                         hlist_del_init_rcu(&p->rlist);
1997
1998                 if (val == 1)
1999                         break;
2000
2001                 del_timer(&p->multicast_router_timer);
2002
2003                 if (val == 0)
2004                         break;
2005
2006                 br_multicast_add_router(br, p);
2007                 break;
2008
2009         default:
2010                 err = -EINVAL;
2011                 break;
2012         }
2013
2014 unlock:
2015         spin_unlock(&br->multicast_lock);
2016
2017         return err;
2018 }
2019
2020 static void br_multicast_start_querier(struct net_bridge *br,
2021                                        struct bridge_mcast_own_query *query)
2022 {
2023         struct net_bridge_port *port;
2024
2025         __br_multicast_open(br, query);
2026
2027         list_for_each_entry(port, &br->port_list, list) {
2028                 if (port->state == BR_STATE_DISABLED ||
2029                     port->state == BR_STATE_BLOCKING)
2030                         continue;
2031
2032                 if (query == &br->ip4_own_query)
2033                         br_multicast_enable(&port->ip4_own_query);
2034 #if IS_ENABLED(CONFIG_IPV6)
2035                 else
2036                         br_multicast_enable(&port->ip6_own_query);
2037 #endif
2038         }
2039 }
2040
2041 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
2042 {
2043         int err = 0;
2044         struct net_bridge_mdb_htable *mdb;
2045
2046         spin_lock_bh(&br->multicast_lock);
2047         if (br->multicast_disabled == !val)
2048                 goto unlock;
2049
2050         br->multicast_disabled = !val;
2051         if (br->multicast_disabled)
2052                 goto unlock;
2053
2054         if (!netif_running(br->dev))
2055                 goto unlock;
2056
2057         mdb = mlock_dereference(br->mdb, br);
2058         if (mdb) {
2059                 if (mdb->old) {
2060                         err = -EEXIST;
2061 rollback:
2062                         br->multicast_disabled = !!val;
2063                         goto unlock;
2064                 }
2065
2066                 err = br_mdb_rehash(&br->mdb, mdb->max,
2067                                     br->hash_elasticity);
2068                 if (err)
2069                         goto rollback;
2070         }
2071
2072         br_multicast_start_querier(br, &br->ip4_own_query);
2073 #if IS_ENABLED(CONFIG_IPV6)
2074         br_multicast_start_querier(br, &br->ip6_own_query);
2075 #endif
2076
2077 unlock:
2078         spin_unlock_bh(&br->multicast_lock);
2079
2080         return err;
2081 }
2082
2083 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
2084 {
2085         unsigned long max_delay;
2086
2087         val = !!val;
2088
2089         spin_lock_bh(&br->multicast_lock);
2090         if (br->multicast_querier == val)
2091                 goto unlock;
2092
2093         br->multicast_querier = val;
2094         if (!val)
2095                 goto unlock;
2096
2097         max_delay = br->multicast_query_response_interval;
2098
2099         if (!timer_pending(&br->ip4_other_query.timer))
2100                 br->ip4_other_query.delay_time = jiffies + max_delay;
2101
2102         br_multicast_start_querier(br, &br->ip4_own_query);
2103
2104 #if IS_ENABLED(CONFIG_IPV6)
2105         if (!timer_pending(&br->ip6_other_query.timer))
2106                 br->ip6_other_query.delay_time = jiffies + max_delay;
2107
2108         br_multicast_start_querier(br, &br->ip6_own_query);
2109 #endif
2110
2111 unlock:
2112         spin_unlock_bh(&br->multicast_lock);
2113
2114         return 0;
2115 }
2116
2117 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2118 {
2119         int err = -ENOENT;
2120         u32 old;
2121         struct net_bridge_mdb_htable *mdb;
2122
2123         spin_lock_bh(&br->multicast_lock);
2124         if (!netif_running(br->dev))
2125                 goto unlock;
2126
2127         err = -EINVAL;
2128         if (!is_power_of_2(val))
2129                 goto unlock;
2130
2131         mdb = mlock_dereference(br->mdb, br);
2132         if (mdb && val < mdb->size)
2133                 goto unlock;
2134
2135         err = 0;
2136
2137         old = br->hash_max;
2138         br->hash_max = val;
2139
2140         if (mdb) {
2141                 if (mdb->old) {
2142                         err = -EEXIST;
2143 rollback:
2144                         br->hash_max = old;
2145                         goto unlock;
2146                 }
2147
2148                 err = br_mdb_rehash(&br->mdb, br->hash_max,
2149                                     br->hash_elasticity);
2150                 if (err)
2151                         goto rollback;
2152         }
2153
2154 unlock:
2155         spin_unlock_bh(&br->multicast_lock);
2156
2157         return err;
2158 }
2159
2160 /**
2161  * br_multicast_list_adjacent - Returns snooped multicast addresses
2162  * @dev:        The bridge port adjacent to which to retrieve addresses
2163  * @br_ip_list: The list to store found, snooped multicast IP addresses in
2164  *
2165  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2166  * snooping feature on all bridge ports of dev's bridge device, excluding
2167  * the addresses from dev itself.
2168  *
2169  * Returns the number of items added to br_ip_list.
2170  *
2171  * Notes:
2172  * - br_ip_list needs to be initialized by caller
2173  * - br_ip_list might contain duplicates in the end
2174  *   (needs to be taken care of by caller)
2175  * - br_ip_list needs to be freed by caller
2176  */
2177 int br_multicast_list_adjacent(struct net_device *dev,
2178                                struct list_head *br_ip_list)
2179 {
2180         struct net_bridge *br;
2181         struct net_bridge_port *port;
2182         struct net_bridge_port_group *group;
2183         struct br_ip_list *entry;
2184         int count = 0;
2185
2186         rcu_read_lock();
2187         if (!br_ip_list || !br_port_exists(dev))
2188                 goto unlock;
2189
2190         port = br_port_get_rcu(dev);
2191         if (!port || !port->br)
2192                 goto unlock;
2193
2194         br = port->br;
2195
2196         list_for_each_entry_rcu(port, &br->port_list, list) {
2197                 if (!port->dev || port->dev == dev)
2198                         continue;
2199
2200                 hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2201                         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2202                         if (!entry)
2203                                 goto unlock;
2204
2205                         entry->addr = group->addr;
2206                         list_add(&entry->list, br_ip_list);
2207                         count++;
2208                 }
2209         }
2210
2211 unlock:
2212         rcu_read_unlock();
2213         return count;
2214 }
2215 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2216
2217 /**
2218  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2219  * @dev: The bridge port providing the bridge on which to check for a querier
2220  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2221  *
2222  * Checks whether the given interface has a bridge on top and if so returns
2223  * true if a valid querier exists anywhere on the bridged link layer.
2224  * Otherwise returns false.
2225  */
2226 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2227 {
2228         struct net_bridge *br;
2229         struct net_bridge_port *port;
2230         struct ethhdr eth;
2231         bool ret = false;
2232
2233         rcu_read_lock();
2234         if (!br_port_exists(dev))
2235                 goto unlock;
2236
2237         port = br_port_get_rcu(dev);
2238         if (!port || !port->br)
2239                 goto unlock;
2240
2241         br = port->br;
2242
2243         memset(&eth, 0, sizeof(eth));
2244         eth.h_proto = htons(proto);
2245
2246         ret = br_multicast_querier_exists(br, &eth);
2247
2248 unlock:
2249         rcu_read_unlock();
2250         return ret;
2251 }
2252 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2253
2254 /**
2255  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2256  * @dev: The bridge port adjacent to which to check for a querier
2257  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2258  *
2259  * Checks whether the given interface has a bridge on top and if so returns
2260  * true if a selected querier is behind one of the other ports of this
2261  * bridge. Otherwise returns false.
2262  */
2263 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2264 {
2265         struct net_bridge *br;
2266         struct net_bridge_port *port;
2267         bool ret = false;
2268
2269         rcu_read_lock();
2270         if (!br_port_exists(dev))
2271                 goto unlock;
2272
2273         port = br_port_get_rcu(dev);
2274         if (!port || !port->br)
2275                 goto unlock;
2276
2277         br = port->br;
2278
2279         switch (proto) {
2280         case ETH_P_IP:
2281                 if (!timer_pending(&br->ip4_other_query.timer) ||
2282                     rcu_dereference(br->ip4_querier.port) == port)
2283                         goto unlock;
2284                 break;
2285 #if IS_ENABLED(CONFIG_IPV6)
2286         case ETH_P_IPV6:
2287                 if (!timer_pending(&br->ip6_other_query.timer) ||
2288                     rcu_dereference(br->ip6_querier.port) == port)
2289                         goto unlock;
2290                 break;
2291 #endif
2292         default:
2293                 goto unlock;
2294         }
2295
2296         ret = true;
2297 unlock:
2298         rcu_read_unlock();
2299         return ret;
2300 }
2301 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);