bridge: check return value of ipv6_dev_get_saddr()
[linux-2.6.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/if_ether.h>
15 #include <linux/igmp.h>
16 #include <linux/jhash.h>
17 #include <linux/kernel.h>
18 #include <linux/log2.h>
19 #include <linux/netdevice.h>
20 #include <linux/netfilter_bridge.h>
21 #include <linux/random.h>
22 #include <linux/rculist.h>
23 #include <linux/skbuff.h>
24 #include <linux/slab.h>
25 #include <linux/timer.h>
26 #include <net/ip.h>
27 #if IS_ENABLED(CONFIG_IPV6)
28 #include <net/ipv6.h>
29 #include <net/mld.h>
30 #include <net/addrconf.h>
31 #include <net/ip6_checksum.h>
32 #endif
33
34 #include "br_private.h"
35
36 #define mlock_dereference(X, br) \
37         rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))
38
39 #if IS_ENABLED(CONFIG_IPV6)
40 static inline int ipv6_is_transient_multicast(const struct in6_addr *addr)
41 {
42         if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr))
43                 return 1;
44         return 0;
45 }
46 #endif
47
48 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
49 {
50         if (a->proto != b->proto)
51                 return 0;
52         switch (a->proto) {
53         case htons(ETH_P_IP):
54                 return a->u.ip4 == b->u.ip4;
55 #if IS_ENABLED(CONFIG_IPV6)
56         case htons(ETH_P_IPV6):
57                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
58 #endif
59         }
60         return 0;
61 }
62
63 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
64 {
65         return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
66 }
67
68 #if IS_ENABLED(CONFIG_IPV6)
69 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
70                                 const struct in6_addr *ip)
71 {
72         return jhash2((__force u32 *)ip->s6_addr32, 4, mdb->secret) & (mdb->max - 1);
73 }
74 #endif
75
76 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
77                              struct br_ip *ip)
78 {
79         switch (ip->proto) {
80         case htons(ETH_P_IP):
81                 return __br_ip4_hash(mdb, ip->u.ip4);
82 #if IS_ENABLED(CONFIG_IPV6)
83         case htons(ETH_P_IPV6):
84                 return __br_ip6_hash(mdb, &ip->u.ip6);
85 #endif
86         }
87         return 0;
88 }
89
90 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
91         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
92 {
93         struct net_bridge_mdb_entry *mp;
94         struct hlist_node *p;
95
96         hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
97                 if (br_ip_equal(&mp->addr, dst))
98                         return mp;
99         }
100
101         return NULL;
102 }
103
104 static struct net_bridge_mdb_entry *br_mdb_ip_get(
105         struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
106 {
107         if (!mdb)
108                 return NULL;
109
110         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
111 }
112
113 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
114         struct net_bridge_mdb_htable *mdb, __be32 dst)
115 {
116         struct br_ip br_dst;
117
118         br_dst.u.ip4 = dst;
119         br_dst.proto = htons(ETH_P_IP);
120
121         return br_mdb_ip_get(mdb, &br_dst);
122 }
123
124 #if IS_ENABLED(CONFIG_IPV6)
125 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
126         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
127 {
128         struct br_ip br_dst;
129
130         br_dst.u.ip6 = *dst;
131         br_dst.proto = htons(ETH_P_IPV6);
132
133         return br_mdb_ip_get(mdb, &br_dst);
134 }
135 #endif
136
137 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
138                                         struct sk_buff *skb)
139 {
140         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
141         struct br_ip ip;
142
143         if (br->multicast_disabled)
144                 return NULL;
145
146         if (BR_INPUT_SKB_CB(skb)->igmp)
147                 return NULL;
148
149         ip.proto = skb->protocol;
150
151         switch (skb->protocol) {
152         case htons(ETH_P_IP):
153                 ip.u.ip4 = ip_hdr(skb)->daddr;
154                 break;
155 #if IS_ENABLED(CONFIG_IPV6)
156         case htons(ETH_P_IPV6):
157                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
158                 break;
159 #endif
160         default:
161                 return NULL;
162         }
163
164         return br_mdb_ip_get(mdb, &ip);
165 }
166
167 static void br_mdb_free(struct rcu_head *head)
168 {
169         struct net_bridge_mdb_htable *mdb =
170                 container_of(head, struct net_bridge_mdb_htable, rcu);
171         struct net_bridge_mdb_htable *old = mdb->old;
172
173         mdb->old = NULL;
174         kfree(old->mhash);
175         kfree(old);
176 }
177
178 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
179                        struct net_bridge_mdb_htable *old,
180                        int elasticity)
181 {
182         struct net_bridge_mdb_entry *mp;
183         struct hlist_node *p;
184         int maxlen;
185         int len;
186         int i;
187
188         for (i = 0; i < old->max; i++)
189                 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
190                         hlist_add_head(&mp->hlist[new->ver],
191                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
192
193         if (!elasticity)
194                 return 0;
195
196         maxlen = 0;
197         for (i = 0; i < new->max; i++) {
198                 len = 0;
199                 hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
200                         len++;
201                 if (len > maxlen)
202                         maxlen = len;
203         }
204
205         return maxlen > elasticity ? -EINVAL : 0;
206 }
207
208 static void br_multicast_free_pg(struct rcu_head *head)
209 {
210         struct net_bridge_port_group *p =
211                 container_of(head, struct net_bridge_port_group, rcu);
212
213         kfree(p);
214 }
215
216 static void br_multicast_free_group(struct rcu_head *head)
217 {
218         struct net_bridge_mdb_entry *mp =
219                 container_of(head, struct net_bridge_mdb_entry, rcu);
220
221         kfree(mp);
222 }
223
224 static void br_multicast_group_expired(unsigned long data)
225 {
226         struct net_bridge_mdb_entry *mp = (void *)data;
227         struct net_bridge *br = mp->br;
228         struct net_bridge_mdb_htable *mdb;
229
230         spin_lock(&br->multicast_lock);
231         if (!netif_running(br->dev) || timer_pending(&mp->timer))
232                 goto out;
233
234         mp->mglist = false;
235
236         if (mp->ports)
237                 goto out;
238
239         mdb = mlock_dereference(br->mdb, br);
240
241         hlist_del_rcu(&mp->hlist[mdb->ver]);
242         mdb->size--;
243
244         del_timer(&mp->query_timer);
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                 del_timer(&p->query_timer);
275                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
276
277                 if (!mp->ports && !mp->mglist &&
278                     netif_running(br->dev))
279                         mod_timer(&mp->timer, jiffies);
280
281                 return;
282         }
283
284         WARN_ON(1);
285 }
286
287 static void br_multicast_port_group_expired(unsigned long data)
288 {
289         struct net_bridge_port_group *pg = (void *)data;
290         struct net_bridge *br = pg->port->br;
291
292         spin_lock(&br->multicast_lock);
293         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
294             hlist_unhashed(&pg->mglist))
295                 goto out;
296
297         br_multicast_del_pg(br, pg);
298
299 out:
300         spin_unlock(&br->multicast_lock);
301 }
302
303 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
304                          int elasticity)
305 {
306         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
307         struct net_bridge_mdb_htable *mdb;
308         int err;
309
310         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
311         if (!mdb)
312                 return -ENOMEM;
313
314         mdb->max = max;
315         mdb->old = old;
316
317         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
318         if (!mdb->mhash) {
319                 kfree(mdb);
320                 return -ENOMEM;
321         }
322
323         mdb->size = old ? old->size : 0;
324         mdb->ver = old ? old->ver ^ 1 : 0;
325
326         if (!old || elasticity)
327                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
328         else
329                 mdb->secret = old->secret;
330
331         if (!old)
332                 goto out;
333
334         err = br_mdb_copy(mdb, old, elasticity);
335         if (err) {
336                 kfree(mdb->mhash);
337                 kfree(mdb);
338                 return err;
339         }
340
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         memcpy(eth->h_source, br->dev->dev_addr, 6);
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 = 0;
389         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
390         ((u8 *)&iph[1])[0] = IPOPT_RA;
391         ((u8 *)&iph[1])[1] = 4;
392         ((u8 *)&iph[1])[2] = 0;
393         ((u8 *)&iph[1])[3] = 0;
394         ip_send_check(iph);
395         skb_put(skb, 24);
396
397         skb_set_transport_header(skb, skb->len);
398         ih = igmp_hdr(skb);
399         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
400         ih->code = (group ? br->multicast_last_member_interval :
401                             br->multicast_query_response_interval) /
402                    (HZ / IGMP_TIMER_SCALE);
403         ih->group = group;
404         ih->csum = 0;
405         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
406         skb_put(skb, sizeof(*ih));
407
408         __skb_pull(skb, sizeof(*eth));
409
410 out:
411         return skb;
412 }
413
414 #if IS_ENABLED(CONFIG_IPV6)
415 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
416                                                     const struct in6_addr *group)
417 {
418         struct sk_buff *skb;
419         struct ipv6hdr *ip6h;
420         struct mld_msg *mldq;
421         struct ethhdr *eth;
422         u8 *hopopt;
423         unsigned long interval;
424
425         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
426                                                  8 + sizeof(*mldq));
427         if (!skb)
428                 goto out;
429
430         skb->protocol = htons(ETH_P_IPV6);
431
432         /* Ethernet header */
433         skb_reset_mac_header(skb);
434         eth = eth_hdr(skb);
435
436         memcpy(eth->h_source, br->dev->dev_addr, 6);
437         eth->h_proto = htons(ETH_P_IPV6);
438         skb_put(skb, sizeof(*eth));
439
440         /* IPv6 header + HbH option */
441         skb_set_network_header(skb, skb->len);
442         ip6h = ipv6_hdr(skb);
443
444         *(__force __be32 *)ip6h = htonl(0x60000000);
445         ip6h->payload_len = htons(8 + sizeof(*mldq));
446         ip6h->nexthdr = IPPROTO_HOPOPTS;
447         ip6h->hop_limit = 1;
448         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
449         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
450                                &ip6h->saddr)) {
451                 kfree_skb(skb);
452                 return NULL;
453         }
454         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
455
456         hopopt = (u8 *)(ip6h + 1);
457         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
458         hopopt[1] = 0;                          /* length of HbH */
459         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
460         hopopt[3] = 2;                          /* Length of RA Option */
461         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
462         hopopt[5] = 0;
463         hopopt[6] = IPV6_TLV_PAD0;              /* Pad0 */
464         hopopt[7] = IPV6_TLV_PAD0;              /* Pad0 */
465
466         skb_put(skb, sizeof(*ip6h) + 8);
467
468         /* ICMPv6 */
469         skb_set_transport_header(skb, skb->len);
470         mldq = (struct mld_msg *) icmp6_hdr(skb);
471
472         interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
473                                           br->multicast_query_response_interval;
474
475         mldq->mld_type = ICMPV6_MGM_QUERY;
476         mldq->mld_code = 0;
477         mldq->mld_cksum = 0;
478         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
479         mldq->mld_reserved = 0;
480         mldq->mld_mca = *group;
481
482         /* checksum */
483         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
484                                           sizeof(*mldq), IPPROTO_ICMPV6,
485                                           csum_partial(mldq,
486                                                        sizeof(*mldq), 0));
487         skb_put(skb, sizeof(*mldq));
488
489         __skb_pull(skb, sizeof(*eth));
490
491 out:
492         return skb;
493 }
494 #endif
495
496 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
497                                                 struct br_ip *addr)
498 {
499         switch (addr->proto) {
500         case htons(ETH_P_IP):
501                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
502 #if IS_ENABLED(CONFIG_IPV6)
503         case htons(ETH_P_IPV6):
504                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
505 #endif
506         }
507         return NULL;
508 }
509
510 static void br_multicast_send_group_query(struct net_bridge_mdb_entry *mp)
511 {
512         struct net_bridge *br = mp->br;
513         struct sk_buff *skb;
514
515         skb = br_multicast_alloc_query(br, &mp->addr);
516         if (!skb)
517                 goto timer;
518
519         netif_rx(skb);
520
521 timer:
522         if (++mp->queries_sent < br->multicast_last_member_count)
523                 mod_timer(&mp->query_timer,
524                           jiffies + br->multicast_last_member_interval);
525 }
526
527 static void br_multicast_group_query_expired(unsigned long data)
528 {
529         struct net_bridge_mdb_entry *mp = (void *)data;
530         struct net_bridge *br = mp->br;
531
532         spin_lock(&br->multicast_lock);
533         if (!netif_running(br->dev) || !mp->mglist ||
534             mp->queries_sent >= br->multicast_last_member_count)
535                 goto out;
536
537         br_multicast_send_group_query(mp);
538
539 out:
540         spin_unlock(&br->multicast_lock);
541 }
542
543 static void br_multicast_send_port_group_query(struct net_bridge_port_group *pg)
544 {
545         struct net_bridge_port *port = pg->port;
546         struct net_bridge *br = port->br;
547         struct sk_buff *skb;
548
549         skb = br_multicast_alloc_query(br, &pg->addr);
550         if (!skb)
551                 goto timer;
552
553         br_deliver(port, skb);
554
555 timer:
556         if (++pg->queries_sent < br->multicast_last_member_count)
557                 mod_timer(&pg->query_timer,
558                           jiffies + br->multicast_last_member_interval);
559 }
560
561 static void br_multicast_port_group_query_expired(unsigned long data)
562 {
563         struct net_bridge_port_group *pg = (void *)data;
564         struct net_bridge_port *port = pg->port;
565         struct net_bridge *br = port->br;
566
567         spin_lock(&br->multicast_lock);
568         if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) ||
569             pg->queries_sent >= br->multicast_last_member_count)
570                 goto out;
571
572         br_multicast_send_port_group_query(pg);
573
574 out:
575         spin_unlock(&br->multicast_lock);
576 }
577
578 static struct net_bridge_mdb_entry *br_multicast_get_group(
579         struct net_bridge *br, struct net_bridge_port *port,
580         struct br_ip *group, int hash)
581 {
582         struct net_bridge_mdb_htable *mdb;
583         struct net_bridge_mdb_entry *mp;
584         struct hlist_node *p;
585         unsigned count = 0;
586         unsigned max;
587         int elasticity;
588         int err;
589
590         mdb = rcu_dereference_protected(br->mdb, 1);
591         hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
592                 count++;
593                 if (unlikely(br_ip_equal(group, &mp->addr)))
594                         return mp;
595         }
596
597         elasticity = 0;
598         max = mdb->max;
599
600         if (unlikely(count > br->hash_elasticity && count)) {
601                 if (net_ratelimit())
602                         br_info(br, "Multicast hash table "
603                                 "chain limit reached: %s\n",
604                                 port ? port->dev->name : br->dev->name);
605
606                 elasticity = br->hash_elasticity;
607         }
608
609         if (mdb->size >= max) {
610                 max *= 2;
611                 if (unlikely(max >= br->hash_max)) {
612                         br_warn(br, "Multicast hash table maximum "
613                                 "reached, disabling snooping: %s, %d\n",
614                                 port ? port->dev->name : br->dev->name, max);
615                         err = -E2BIG;
616 disable:
617                         br->multicast_disabled = 1;
618                         goto err;
619                 }
620         }
621
622         if (max > mdb->max || elasticity) {
623                 if (mdb->old) {
624                         if (net_ratelimit())
625                                 br_info(br, "Multicast hash table "
626                                         "on fire: %s\n",
627                                         port ? port->dev->name : br->dev->name);
628                         err = -EEXIST;
629                         goto err;
630                 }
631
632                 err = br_mdb_rehash(&br->mdb, max, elasticity);
633                 if (err) {
634                         br_warn(br, "Cannot rehash multicast "
635                                 "hash table, disabling snooping: %s, %d, %d\n",
636                                 port ? port->dev->name : br->dev->name,
637                                 mdb->size, err);
638                         goto disable;
639                 }
640
641                 err = -EAGAIN;
642                 goto err;
643         }
644
645         return NULL;
646
647 err:
648         mp = ERR_PTR(err);
649         return mp;
650 }
651
652 static struct net_bridge_mdb_entry *br_multicast_new_group(
653         struct net_bridge *br, struct net_bridge_port *port,
654         struct br_ip *group)
655 {
656         struct net_bridge_mdb_htable *mdb;
657         struct net_bridge_mdb_entry *mp;
658         int hash;
659         int err;
660
661         mdb = rcu_dereference_protected(br->mdb, 1);
662         if (!mdb) {
663                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
664                 if (err)
665                         return ERR_PTR(err);
666                 goto rehash;
667         }
668
669         hash = br_ip_hash(mdb, group);
670         mp = br_multicast_get_group(br, port, group, hash);
671         switch (PTR_ERR(mp)) {
672         case 0:
673                 break;
674
675         case -EAGAIN:
676 rehash:
677                 mdb = rcu_dereference_protected(br->mdb, 1);
678                 hash = br_ip_hash(mdb, group);
679                 break;
680
681         default:
682                 goto out;
683         }
684
685         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
686         if (unlikely(!mp))
687                 return ERR_PTR(-ENOMEM);
688
689         mp->br = br;
690         mp->addr = *group;
691         setup_timer(&mp->timer, br_multicast_group_expired,
692                     (unsigned long)mp);
693         setup_timer(&mp->query_timer, br_multicast_group_query_expired,
694                     (unsigned long)mp);
695
696         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
697         mdb->size++;
698
699 out:
700         return mp;
701 }
702
703 static int br_multicast_add_group(struct net_bridge *br,
704                                   struct net_bridge_port *port,
705                                   struct br_ip *group)
706 {
707         struct net_bridge_mdb_entry *mp;
708         struct net_bridge_port_group *p;
709         struct net_bridge_port_group __rcu **pp;
710         unsigned long now = jiffies;
711         int err;
712
713         spin_lock(&br->multicast_lock);
714         if (!netif_running(br->dev) ||
715             (port && port->state == BR_STATE_DISABLED))
716                 goto out;
717
718         mp = br_multicast_new_group(br, port, group);
719         err = PTR_ERR(mp);
720         if (IS_ERR(mp))
721                 goto err;
722
723         if (!port) {
724                 mp->mglist = true;
725                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
726                 goto out;
727         }
728
729         for (pp = &mp->ports;
730              (p = mlock_dereference(*pp, br)) != NULL;
731              pp = &p->next) {
732                 if (p->port == port)
733                         goto found;
734                 if ((unsigned long)p->port < (unsigned long)port)
735                         break;
736         }
737
738         p = kzalloc(sizeof(*p), GFP_ATOMIC);
739         err = -ENOMEM;
740         if (unlikely(!p))
741                 goto err;
742
743         p->addr = *group;
744         p->port = port;
745         p->next = *pp;
746         hlist_add_head(&p->mglist, &port->mglist);
747         setup_timer(&p->timer, br_multicast_port_group_expired,
748                     (unsigned long)p);
749         setup_timer(&p->query_timer, br_multicast_port_group_query_expired,
750                     (unsigned long)p);
751
752         rcu_assign_pointer(*pp, p);
753
754 found:
755         mod_timer(&p->timer, now + br->multicast_membership_interval);
756 out:
757         err = 0;
758
759 err:
760         spin_unlock(&br->multicast_lock);
761         return err;
762 }
763
764 static int br_ip4_multicast_add_group(struct net_bridge *br,
765                                       struct net_bridge_port *port,
766                                       __be32 group)
767 {
768         struct br_ip br_group;
769
770         if (ipv4_is_local_multicast(group))
771                 return 0;
772
773         br_group.u.ip4 = group;
774         br_group.proto = htons(ETH_P_IP);
775
776         return br_multicast_add_group(br, port, &br_group);
777 }
778
779 #if IS_ENABLED(CONFIG_IPV6)
780 static int br_ip6_multicast_add_group(struct net_bridge *br,
781                                       struct net_bridge_port *port,
782                                       const struct in6_addr *group)
783 {
784         struct br_ip br_group;
785
786         if (!ipv6_is_transient_multicast(group))
787                 return 0;
788
789         br_group.u.ip6 = *group;
790         br_group.proto = htons(ETH_P_IPV6);
791
792         return br_multicast_add_group(br, port, &br_group);
793 }
794 #endif
795
796 static void br_multicast_router_expired(unsigned long data)
797 {
798         struct net_bridge_port *port = (void *)data;
799         struct net_bridge *br = port->br;
800
801         spin_lock(&br->multicast_lock);
802         if (port->multicast_router != 1 ||
803             timer_pending(&port->multicast_router_timer) ||
804             hlist_unhashed(&port->rlist))
805                 goto out;
806
807         hlist_del_init_rcu(&port->rlist);
808
809 out:
810         spin_unlock(&br->multicast_lock);
811 }
812
813 static void br_multicast_local_router_expired(unsigned long data)
814 {
815 }
816
817 static void __br_multicast_send_query(struct net_bridge *br,
818                                       struct net_bridge_port *port,
819                                       struct br_ip *ip)
820 {
821         struct sk_buff *skb;
822
823         skb = br_multicast_alloc_query(br, ip);
824         if (!skb)
825                 return;
826
827         if (port) {
828                 __skb_push(skb, sizeof(struct ethhdr));
829                 skb->dev = port->dev;
830                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
831                         dev_queue_xmit);
832         } else
833                 netif_rx(skb);
834 }
835
836 static void br_multicast_send_query(struct net_bridge *br,
837                                     struct net_bridge_port *port, u32 sent)
838 {
839         unsigned long time;
840         struct br_ip br_group;
841
842         if (!netif_running(br->dev) || br->multicast_disabled ||
843             timer_pending(&br->multicast_querier_timer))
844                 return;
845
846         memset(&br_group.u, 0, sizeof(br_group.u));
847
848         br_group.proto = htons(ETH_P_IP);
849         __br_multicast_send_query(br, port, &br_group);
850
851 #if IS_ENABLED(CONFIG_IPV6)
852         br_group.proto = htons(ETH_P_IPV6);
853         __br_multicast_send_query(br, port, &br_group);
854 #endif
855
856         time = jiffies;
857         time += sent < br->multicast_startup_query_count ?
858                 br->multicast_startup_query_interval :
859                 br->multicast_query_interval;
860         mod_timer(port ? &port->multicast_query_timer :
861                          &br->multicast_query_timer, time);
862 }
863
864 static void br_multicast_port_query_expired(unsigned long data)
865 {
866         struct net_bridge_port *port = (void *)data;
867         struct net_bridge *br = port->br;
868
869         spin_lock(&br->multicast_lock);
870         if (port->state == BR_STATE_DISABLED ||
871             port->state == BR_STATE_BLOCKING)
872                 goto out;
873
874         if (port->multicast_startup_queries_sent <
875             br->multicast_startup_query_count)
876                 port->multicast_startup_queries_sent++;
877
878         br_multicast_send_query(port->br, port,
879                                 port->multicast_startup_queries_sent);
880
881 out:
882         spin_unlock(&br->multicast_lock);
883 }
884
885 void br_multicast_add_port(struct net_bridge_port *port)
886 {
887         port->multicast_router = 1;
888
889         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
890                     (unsigned long)port);
891         setup_timer(&port->multicast_query_timer,
892                     br_multicast_port_query_expired, (unsigned long)port);
893 }
894
895 void br_multicast_del_port(struct net_bridge_port *port)
896 {
897         del_timer_sync(&port->multicast_router_timer);
898 }
899
900 static void __br_multicast_enable_port(struct net_bridge_port *port)
901 {
902         port->multicast_startup_queries_sent = 0;
903
904         if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
905             del_timer(&port->multicast_query_timer))
906                 mod_timer(&port->multicast_query_timer, jiffies);
907 }
908
909 void br_multicast_enable_port(struct net_bridge_port *port)
910 {
911         struct net_bridge *br = port->br;
912
913         spin_lock(&br->multicast_lock);
914         if (br->multicast_disabled || !netif_running(br->dev))
915                 goto out;
916
917         __br_multicast_enable_port(port);
918
919 out:
920         spin_unlock(&br->multicast_lock);
921 }
922
923 void br_multicast_disable_port(struct net_bridge_port *port)
924 {
925         struct net_bridge *br = port->br;
926         struct net_bridge_port_group *pg;
927         struct hlist_node *p, *n;
928
929         spin_lock(&br->multicast_lock);
930         hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
931                 br_multicast_del_pg(br, pg);
932
933         if (!hlist_unhashed(&port->rlist))
934                 hlist_del_init_rcu(&port->rlist);
935         del_timer(&port->multicast_router_timer);
936         del_timer(&port->multicast_query_timer);
937         spin_unlock(&br->multicast_lock);
938 }
939
940 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
941                                          struct net_bridge_port *port,
942                                          struct sk_buff *skb)
943 {
944         struct igmpv3_report *ih;
945         struct igmpv3_grec *grec;
946         int i;
947         int len;
948         int num;
949         int type;
950         int err = 0;
951         __be32 group;
952
953         if (!pskb_may_pull(skb, sizeof(*ih)))
954                 return -EINVAL;
955
956         ih = igmpv3_report_hdr(skb);
957         num = ntohs(ih->ngrec);
958         len = sizeof(*ih);
959
960         for (i = 0; i < num; i++) {
961                 len += sizeof(*grec);
962                 if (!pskb_may_pull(skb, len))
963                         return -EINVAL;
964
965                 grec = (void *)(skb->data + len - sizeof(*grec));
966                 group = grec->grec_mca;
967                 type = grec->grec_type;
968
969                 len += ntohs(grec->grec_nsrcs) * 4;
970                 if (!pskb_may_pull(skb, len))
971                         return -EINVAL;
972
973                 /* We treat this as an IGMPv2 report for now. */
974                 switch (type) {
975                 case IGMPV3_MODE_IS_INCLUDE:
976                 case IGMPV3_MODE_IS_EXCLUDE:
977                 case IGMPV3_CHANGE_TO_INCLUDE:
978                 case IGMPV3_CHANGE_TO_EXCLUDE:
979                 case IGMPV3_ALLOW_NEW_SOURCES:
980                 case IGMPV3_BLOCK_OLD_SOURCES:
981                         break;
982
983                 default:
984                         continue;
985                 }
986
987                 err = br_ip4_multicast_add_group(br, port, group);
988                 if (err)
989                         break;
990         }
991
992         return err;
993 }
994
995 #if IS_ENABLED(CONFIG_IPV6)
996 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
997                                         struct net_bridge_port *port,
998                                         struct sk_buff *skb)
999 {
1000         struct icmp6hdr *icmp6h;
1001         struct mld2_grec *grec;
1002         int i;
1003         int len;
1004         int num;
1005         int err = 0;
1006
1007         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1008                 return -EINVAL;
1009
1010         icmp6h = icmp6_hdr(skb);
1011         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1012         len = sizeof(*icmp6h);
1013
1014         for (i = 0; i < num; i++) {
1015                 __be16 *nsrcs, _nsrcs;
1016
1017                 nsrcs = skb_header_pointer(skb,
1018                                            len + offsetof(struct mld2_grec,
1019                                                           grec_nsrcs),
1020                                            sizeof(_nsrcs), &_nsrcs);
1021                 if (!nsrcs)
1022                         return -EINVAL;
1023
1024                 if (!pskb_may_pull(skb,
1025                                    len + sizeof(*grec) +
1026                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1027                         return -EINVAL;
1028
1029                 grec = (struct mld2_grec *)(skb->data + len);
1030                 len += sizeof(*grec) +
1031                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1032
1033                 /* We treat these as MLDv1 reports for now. */
1034                 switch (grec->grec_type) {
1035                 case MLD2_MODE_IS_INCLUDE:
1036                 case MLD2_MODE_IS_EXCLUDE:
1037                 case MLD2_CHANGE_TO_INCLUDE:
1038                 case MLD2_CHANGE_TO_EXCLUDE:
1039                 case MLD2_ALLOW_NEW_SOURCES:
1040                 case MLD2_BLOCK_OLD_SOURCES:
1041                         break;
1042
1043                 default:
1044                         continue;
1045                 }
1046
1047                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
1048                 if (!err)
1049                         break;
1050         }
1051
1052         return err;
1053 }
1054 #endif
1055
1056 /*
1057  * Add port to rotuer_list
1058  *  list is maintained ordered by pointer value
1059  *  and locked by br->multicast_lock and RCU
1060  */
1061 static void br_multicast_add_router(struct net_bridge *br,
1062                                     struct net_bridge_port *port)
1063 {
1064         struct net_bridge_port *p;
1065         struct hlist_node *n, *slot = NULL;
1066
1067         hlist_for_each_entry(p, n, &br->router_list, rlist) {
1068                 if ((unsigned long) port >= (unsigned long) p)
1069                         break;
1070                 slot = n;
1071         }
1072
1073         if (slot)
1074                 hlist_add_after_rcu(slot, &port->rlist);
1075         else
1076                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1077 }
1078
1079 static void br_multicast_mark_router(struct net_bridge *br,
1080                                      struct net_bridge_port *port)
1081 {
1082         unsigned long now = jiffies;
1083
1084         if (!port) {
1085                 if (br->multicast_router == 1)
1086                         mod_timer(&br->multicast_router_timer,
1087                                   now + br->multicast_querier_interval);
1088                 return;
1089         }
1090
1091         if (port->multicast_router != 1)
1092                 return;
1093
1094         if (!hlist_unhashed(&port->rlist))
1095                 goto timer;
1096
1097         br_multicast_add_router(br, port);
1098
1099 timer:
1100         mod_timer(&port->multicast_router_timer,
1101                   now + br->multicast_querier_interval);
1102 }
1103
1104 static void br_multicast_query_received(struct net_bridge *br,
1105                                         struct net_bridge_port *port,
1106                                         int saddr)
1107 {
1108         if (saddr)
1109                 mod_timer(&br->multicast_querier_timer,
1110                           jiffies + br->multicast_querier_interval);
1111         else if (timer_pending(&br->multicast_querier_timer))
1112                 return;
1113
1114         br_multicast_mark_router(br, port);
1115 }
1116
1117 static int br_ip4_multicast_query(struct net_bridge *br,
1118                                   struct net_bridge_port *port,
1119                                   struct sk_buff *skb)
1120 {
1121         const struct iphdr *iph = ip_hdr(skb);
1122         struct igmphdr *ih = igmp_hdr(skb);
1123         struct net_bridge_mdb_entry *mp;
1124         struct igmpv3_query *ih3;
1125         struct net_bridge_port_group *p;
1126         struct net_bridge_port_group __rcu **pp;
1127         unsigned long max_delay;
1128         unsigned long now = jiffies;
1129         __be32 group;
1130         int err = 0;
1131
1132         spin_lock(&br->multicast_lock);
1133         if (!netif_running(br->dev) ||
1134             (port && port->state == BR_STATE_DISABLED))
1135                 goto out;
1136
1137         br_multicast_query_received(br, port, !!iph->saddr);
1138
1139         group = ih->group;
1140
1141         if (skb->len == sizeof(*ih)) {
1142                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1143
1144                 if (!max_delay) {
1145                         max_delay = 10 * HZ;
1146                         group = 0;
1147                 }
1148         } else {
1149                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1150                         err = -EINVAL;
1151                         goto out;
1152                 }
1153
1154                 ih3 = igmpv3_query_hdr(skb);
1155                 if (ih3->nsrcs)
1156                         goto out;
1157
1158                 max_delay = ih3->code ?
1159                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1160         }
1161
1162         if (!group)
1163                 goto out;
1164
1165         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
1166         if (!mp)
1167                 goto out;
1168
1169         max_delay *= br->multicast_last_member_count;
1170
1171         if (mp->mglist &&
1172             (timer_pending(&mp->timer) ?
1173              time_after(mp->timer.expires, now + max_delay) :
1174              try_to_del_timer_sync(&mp->timer) >= 0))
1175                 mod_timer(&mp->timer, now + max_delay);
1176
1177         for (pp = &mp->ports;
1178              (p = mlock_dereference(*pp, br)) != NULL;
1179              pp = &p->next) {
1180                 if (timer_pending(&p->timer) ?
1181                     time_after(p->timer.expires, now + max_delay) :
1182                     try_to_del_timer_sync(&p->timer) >= 0)
1183                         mod_timer(&p->timer, now + max_delay);
1184         }
1185
1186 out:
1187         spin_unlock(&br->multicast_lock);
1188         return err;
1189 }
1190
1191 #if IS_ENABLED(CONFIG_IPV6)
1192 static int br_ip6_multicast_query(struct net_bridge *br,
1193                                   struct net_bridge_port *port,
1194                                   struct sk_buff *skb)
1195 {
1196         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1197         struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
1198         struct net_bridge_mdb_entry *mp;
1199         struct mld2_query *mld2q;
1200         struct net_bridge_port_group *p;
1201         struct net_bridge_port_group __rcu **pp;
1202         unsigned long max_delay;
1203         unsigned long now = jiffies;
1204         const struct in6_addr *group = NULL;
1205         int err = 0;
1206
1207         spin_lock(&br->multicast_lock);
1208         if (!netif_running(br->dev) ||
1209             (port && port->state == BR_STATE_DISABLED))
1210                 goto out;
1211
1212         br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1213
1214         if (skb->len == sizeof(*mld)) {
1215                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1216                         err = -EINVAL;
1217                         goto out;
1218                 }
1219                 mld = (struct mld_msg *) icmp6_hdr(skb);
1220                 max_delay = msecs_to_jiffies(htons(mld->mld_maxdelay));
1221                 if (max_delay)
1222                         group = &mld->mld_mca;
1223         } else if (skb->len >= sizeof(*mld2q)) {
1224                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1225                         err = -EINVAL;
1226                         goto out;
1227                 }
1228                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1229                 if (!mld2q->mld2q_nsrcs)
1230                         group = &mld2q->mld2q_mca;
1231                 max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(mld2q->mld2q_mrc) : 1;
1232         }
1233
1234         if (!group)
1235                 goto out;
1236
1237         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
1238         if (!mp)
1239                 goto out;
1240
1241         max_delay *= br->multicast_last_member_count;
1242         if (mp->mglist &&
1243             (timer_pending(&mp->timer) ?
1244              time_after(mp->timer.expires, now + max_delay) :
1245              try_to_del_timer_sync(&mp->timer) >= 0))
1246                 mod_timer(&mp->timer, now + max_delay);
1247
1248         for (pp = &mp->ports;
1249              (p = mlock_dereference(*pp, br)) != NULL;
1250              pp = &p->next) {
1251                 if (timer_pending(&p->timer) ?
1252                     time_after(p->timer.expires, now + max_delay) :
1253                     try_to_del_timer_sync(&p->timer) >= 0)
1254                         mod_timer(&p->timer, now + max_delay);
1255         }
1256
1257 out:
1258         spin_unlock(&br->multicast_lock);
1259         return err;
1260 }
1261 #endif
1262
1263 static void br_multicast_leave_group(struct net_bridge *br,
1264                                      struct net_bridge_port *port,
1265                                      struct br_ip *group)
1266 {
1267         struct net_bridge_mdb_htable *mdb;
1268         struct net_bridge_mdb_entry *mp;
1269         struct net_bridge_port_group *p;
1270         unsigned long now;
1271         unsigned long time;
1272
1273         spin_lock(&br->multicast_lock);
1274         if (!netif_running(br->dev) ||
1275             (port && port->state == BR_STATE_DISABLED) ||
1276             timer_pending(&br->multicast_querier_timer))
1277                 goto out;
1278
1279         mdb = mlock_dereference(br->mdb, br);
1280         mp = br_mdb_ip_get(mdb, group);
1281         if (!mp)
1282                 goto out;
1283
1284         now = jiffies;
1285         time = now + br->multicast_last_member_count *
1286                      br->multicast_last_member_interval;
1287
1288         if (!port) {
1289                 if (mp->mglist &&
1290                     (timer_pending(&mp->timer) ?
1291                      time_after(mp->timer.expires, time) :
1292                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1293                         mod_timer(&mp->timer, time);
1294
1295                         mp->queries_sent = 0;
1296                         mod_timer(&mp->query_timer, now);
1297                 }
1298
1299                 goto out;
1300         }
1301
1302         for (p = mlock_dereference(mp->ports, br);
1303              p != NULL;
1304              p = mlock_dereference(p->next, br)) {
1305                 if (p->port != port)
1306                         continue;
1307
1308                 if (!hlist_unhashed(&p->mglist) &&
1309                     (timer_pending(&p->timer) ?
1310                      time_after(p->timer.expires, time) :
1311                      try_to_del_timer_sync(&p->timer) >= 0)) {
1312                         mod_timer(&p->timer, time);
1313
1314                         p->queries_sent = 0;
1315                         mod_timer(&p->query_timer, now);
1316                 }
1317
1318                 break;
1319         }
1320
1321 out:
1322         spin_unlock(&br->multicast_lock);
1323 }
1324
1325 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1326                                          struct net_bridge_port *port,
1327                                          __be32 group)
1328 {
1329         struct br_ip br_group;
1330
1331         if (ipv4_is_local_multicast(group))
1332                 return;
1333
1334         br_group.u.ip4 = group;
1335         br_group.proto = htons(ETH_P_IP);
1336
1337         br_multicast_leave_group(br, port, &br_group);
1338 }
1339
1340 #if IS_ENABLED(CONFIG_IPV6)
1341 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1342                                          struct net_bridge_port *port,
1343                                          const struct in6_addr *group)
1344 {
1345         struct br_ip br_group;
1346
1347         if (!ipv6_is_transient_multicast(group))
1348                 return;
1349
1350         br_group.u.ip6 = *group;
1351         br_group.proto = htons(ETH_P_IPV6);
1352
1353         br_multicast_leave_group(br, port, &br_group);
1354 }
1355 #endif
1356
1357 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1358                                  struct net_bridge_port *port,
1359                                  struct sk_buff *skb)
1360 {
1361         struct sk_buff *skb2 = skb;
1362         const struct iphdr *iph;
1363         struct igmphdr *ih;
1364         unsigned len;
1365         unsigned offset;
1366         int err;
1367
1368         /* We treat OOM as packet loss for now. */
1369         if (!pskb_may_pull(skb, sizeof(*iph)))
1370                 return -EINVAL;
1371
1372         iph = ip_hdr(skb);
1373
1374         if (iph->ihl < 5 || iph->version != 4)
1375                 return -EINVAL;
1376
1377         if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1378                 return -EINVAL;
1379
1380         iph = ip_hdr(skb);
1381
1382         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1383                 return -EINVAL;
1384
1385         if (iph->protocol != IPPROTO_IGMP) {
1386                 if ((iph->daddr & IGMP_LOCAL_GROUP_MASK) != IGMP_LOCAL_GROUP)
1387                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1388                 return 0;
1389         }
1390
1391         len = ntohs(iph->tot_len);
1392         if (skb->len < len || len < ip_hdrlen(skb))
1393                 return -EINVAL;
1394
1395         if (skb->len > len) {
1396                 skb2 = skb_clone(skb, GFP_ATOMIC);
1397                 if (!skb2)
1398                         return -ENOMEM;
1399
1400                 err = pskb_trim_rcsum(skb2, len);
1401                 if (err)
1402                         goto err_out;
1403         }
1404
1405         len -= ip_hdrlen(skb2);
1406         offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1407         __skb_pull(skb2, offset);
1408         skb_reset_transport_header(skb2);
1409
1410         err = -EINVAL;
1411         if (!pskb_may_pull(skb2, sizeof(*ih)))
1412                 goto out;
1413
1414         switch (skb2->ip_summed) {
1415         case CHECKSUM_COMPLETE:
1416                 if (!csum_fold(skb2->csum))
1417                         break;
1418                 /* fall through */
1419         case CHECKSUM_NONE:
1420                 skb2->csum = 0;
1421                 if (skb_checksum_complete(skb2))
1422                         goto out;
1423         }
1424
1425         err = 0;
1426
1427         BR_INPUT_SKB_CB(skb)->igmp = 1;
1428         ih = igmp_hdr(skb2);
1429
1430         switch (ih->type) {
1431         case IGMP_HOST_MEMBERSHIP_REPORT:
1432         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1433                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1434                 err = br_ip4_multicast_add_group(br, port, ih->group);
1435                 break;
1436         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1437                 err = br_ip4_multicast_igmp3_report(br, port, skb2);
1438                 break;
1439         case IGMP_HOST_MEMBERSHIP_QUERY:
1440                 err = br_ip4_multicast_query(br, port, skb2);
1441                 break;
1442         case IGMP_HOST_LEAVE_MESSAGE:
1443                 br_ip4_multicast_leave_group(br, port, ih->group);
1444                 break;
1445         }
1446
1447 out:
1448         __skb_push(skb2, offset);
1449 err_out:
1450         if (skb2 != skb)
1451                 kfree_skb(skb2);
1452         return err;
1453 }
1454
1455 #if IS_ENABLED(CONFIG_IPV6)
1456 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1457                                  struct net_bridge_port *port,
1458                                  struct sk_buff *skb)
1459 {
1460         struct sk_buff *skb2;
1461         const struct ipv6hdr *ip6h;
1462         u8 icmp6_type;
1463         u8 nexthdr;
1464         __be16 frag_off;
1465         unsigned len;
1466         int offset;
1467         int err;
1468
1469         if (!pskb_may_pull(skb, sizeof(*ip6h)))
1470                 return -EINVAL;
1471
1472         ip6h = ipv6_hdr(skb);
1473
1474         /*
1475          * We're interested in MLD messages only.
1476          *  - Version is 6
1477          *  - MLD has always Router Alert hop-by-hop option
1478          *  - But we do not support jumbrograms.
1479          */
1480         if (ip6h->version != 6 ||
1481             ip6h->nexthdr != IPPROTO_HOPOPTS ||
1482             ip6h->payload_len == 0)
1483                 return 0;
1484
1485         len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1486         if (skb->len < len)
1487                 return -EINVAL;
1488
1489         nexthdr = ip6h->nexthdr;
1490         offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1491
1492         if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1493                 return 0;
1494
1495         /* Okay, we found ICMPv6 header */
1496         skb2 = skb_clone(skb, GFP_ATOMIC);
1497         if (!skb2)
1498                 return -ENOMEM;
1499
1500         err = -EINVAL;
1501         if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1502                 goto out;
1503
1504         len -= offset - skb_network_offset(skb2);
1505
1506         __skb_pull(skb2, offset);
1507         skb_reset_transport_header(skb2);
1508         skb_postpull_rcsum(skb2, skb_network_header(skb2),
1509                            skb_network_header_len(skb2));
1510
1511         icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1512
1513         switch (icmp6_type) {
1514         case ICMPV6_MGM_QUERY:
1515         case ICMPV6_MGM_REPORT:
1516         case ICMPV6_MGM_REDUCTION:
1517         case ICMPV6_MLD2_REPORT:
1518                 break;
1519         default:
1520                 err = 0;
1521                 goto out;
1522         }
1523
1524         /* Okay, we found MLD message. Check further. */
1525         if (skb2->len > len) {
1526                 err = pskb_trim_rcsum(skb2, len);
1527                 if (err)
1528                         goto out;
1529                 err = -EINVAL;
1530         }
1531
1532         ip6h = ipv6_hdr(skb2);
1533
1534         switch (skb2->ip_summed) {
1535         case CHECKSUM_COMPLETE:
1536                 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1537                                         IPPROTO_ICMPV6, skb2->csum))
1538                         break;
1539                 /*FALLTHROUGH*/
1540         case CHECKSUM_NONE:
1541                 skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1542                                                         &ip6h->daddr,
1543                                                         skb2->len,
1544                                                         IPPROTO_ICMPV6, 0));
1545                 if (__skb_checksum_complete(skb2))
1546                         goto out;
1547         }
1548
1549         err = 0;
1550
1551         BR_INPUT_SKB_CB(skb)->igmp = 1;
1552
1553         switch (icmp6_type) {
1554         case ICMPV6_MGM_REPORT:
1555             {
1556                 struct mld_msg *mld;
1557                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1558                         err = -EINVAL;
1559                         goto out;
1560                 }
1561                 mld = (struct mld_msg *)skb_transport_header(skb2);
1562                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1563                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
1564                 break;
1565             }
1566         case ICMPV6_MLD2_REPORT:
1567                 err = br_ip6_multicast_mld2_report(br, port, skb2);
1568                 break;
1569         case ICMPV6_MGM_QUERY:
1570                 err = br_ip6_multicast_query(br, port, skb2);
1571                 break;
1572         case ICMPV6_MGM_REDUCTION:
1573             {
1574                 struct mld_msg *mld;
1575                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1576                         err = -EINVAL;
1577                         goto out;
1578                 }
1579                 mld = (struct mld_msg *)skb_transport_header(skb2);
1580                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
1581             }
1582         }
1583
1584 out:
1585         kfree_skb(skb2);
1586         return err;
1587 }
1588 #endif
1589
1590 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1591                      struct sk_buff *skb)
1592 {
1593         BR_INPUT_SKB_CB(skb)->igmp = 0;
1594         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1595
1596         if (br->multicast_disabled)
1597                 return 0;
1598
1599         switch (skb->protocol) {
1600         case htons(ETH_P_IP):
1601                 return br_multicast_ipv4_rcv(br, port, skb);
1602 #if IS_ENABLED(CONFIG_IPV6)
1603         case htons(ETH_P_IPV6):
1604                 return br_multicast_ipv6_rcv(br, port, skb);
1605 #endif
1606         }
1607
1608         return 0;
1609 }
1610
1611 static void br_multicast_query_expired(unsigned long data)
1612 {
1613         struct net_bridge *br = (void *)data;
1614
1615         spin_lock(&br->multicast_lock);
1616         if (br->multicast_startup_queries_sent <
1617             br->multicast_startup_query_count)
1618                 br->multicast_startup_queries_sent++;
1619
1620         br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1621
1622         spin_unlock(&br->multicast_lock);
1623 }
1624
1625 void br_multicast_init(struct net_bridge *br)
1626 {
1627         br->hash_elasticity = 4;
1628         br->hash_max = 512;
1629
1630         br->multicast_router = 1;
1631         br->multicast_last_member_count = 2;
1632         br->multicast_startup_query_count = 2;
1633
1634         br->multicast_last_member_interval = HZ;
1635         br->multicast_query_response_interval = 10 * HZ;
1636         br->multicast_startup_query_interval = 125 * HZ / 4;
1637         br->multicast_query_interval = 125 * HZ;
1638         br->multicast_querier_interval = 255 * HZ;
1639         br->multicast_membership_interval = 260 * HZ;
1640
1641         spin_lock_init(&br->multicast_lock);
1642         setup_timer(&br->multicast_router_timer,
1643                     br_multicast_local_router_expired, 0);
1644         setup_timer(&br->multicast_querier_timer,
1645                     br_multicast_local_router_expired, 0);
1646         setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1647                     (unsigned long)br);
1648 }
1649
1650 void br_multicast_open(struct net_bridge *br)
1651 {
1652         br->multicast_startup_queries_sent = 0;
1653
1654         if (br->multicast_disabled)
1655                 return;
1656
1657         mod_timer(&br->multicast_query_timer, jiffies);
1658 }
1659
1660 void br_multicast_stop(struct net_bridge *br)
1661 {
1662         struct net_bridge_mdb_htable *mdb;
1663         struct net_bridge_mdb_entry *mp;
1664         struct hlist_node *p, *n;
1665         u32 ver;
1666         int i;
1667
1668         del_timer_sync(&br->multicast_router_timer);
1669         del_timer_sync(&br->multicast_querier_timer);
1670         del_timer_sync(&br->multicast_query_timer);
1671
1672         spin_lock_bh(&br->multicast_lock);
1673         mdb = mlock_dereference(br->mdb, br);
1674         if (!mdb)
1675                 goto out;
1676
1677         br->mdb = NULL;
1678
1679         ver = mdb->ver;
1680         for (i = 0; i < mdb->max; i++) {
1681                 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
1682                                           hlist[ver]) {
1683                         del_timer(&mp->timer);
1684                         del_timer(&mp->query_timer);
1685                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1686                 }
1687         }
1688
1689         if (mdb->old) {
1690                 spin_unlock_bh(&br->multicast_lock);
1691                 rcu_barrier_bh();
1692                 spin_lock_bh(&br->multicast_lock);
1693                 WARN_ON(mdb->old);
1694         }
1695
1696         mdb->old = mdb;
1697         call_rcu_bh(&mdb->rcu, br_mdb_free);
1698
1699 out:
1700         spin_unlock_bh(&br->multicast_lock);
1701 }
1702
1703 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1704 {
1705         int err = -ENOENT;
1706
1707         spin_lock_bh(&br->multicast_lock);
1708         if (!netif_running(br->dev))
1709                 goto unlock;
1710
1711         switch (val) {
1712         case 0:
1713         case 2:
1714                 del_timer(&br->multicast_router_timer);
1715                 /* fall through */
1716         case 1:
1717                 br->multicast_router = val;
1718                 err = 0;
1719                 break;
1720
1721         default:
1722                 err = -EINVAL;
1723                 break;
1724         }
1725
1726 unlock:
1727         spin_unlock_bh(&br->multicast_lock);
1728
1729         return err;
1730 }
1731
1732 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1733 {
1734         struct net_bridge *br = p->br;
1735         int err = -ENOENT;
1736
1737         spin_lock(&br->multicast_lock);
1738         if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1739                 goto unlock;
1740
1741         switch (val) {
1742         case 0:
1743         case 1:
1744         case 2:
1745                 p->multicast_router = val;
1746                 err = 0;
1747
1748                 if (val < 2 && !hlist_unhashed(&p->rlist))
1749                         hlist_del_init_rcu(&p->rlist);
1750
1751                 if (val == 1)
1752                         break;
1753
1754                 del_timer(&p->multicast_router_timer);
1755
1756                 if (val == 0)
1757                         break;
1758
1759                 br_multicast_add_router(br, p);
1760                 break;
1761
1762         default:
1763                 err = -EINVAL;
1764                 break;
1765         }
1766
1767 unlock:
1768         spin_unlock(&br->multicast_lock);
1769
1770         return err;
1771 }
1772
1773 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1774 {
1775         struct net_bridge_port *port;
1776         int err = 0;
1777         struct net_bridge_mdb_htable *mdb;
1778
1779         spin_lock_bh(&br->multicast_lock);
1780         if (br->multicast_disabled == !val)
1781                 goto unlock;
1782
1783         br->multicast_disabled = !val;
1784         if (br->multicast_disabled)
1785                 goto unlock;
1786
1787         if (!netif_running(br->dev))
1788                 goto unlock;
1789
1790         mdb = mlock_dereference(br->mdb, br);
1791         if (mdb) {
1792                 if (mdb->old) {
1793                         err = -EEXIST;
1794 rollback:
1795                         br->multicast_disabled = !!val;
1796                         goto unlock;
1797                 }
1798
1799                 err = br_mdb_rehash(&br->mdb, mdb->max,
1800                                     br->hash_elasticity);
1801                 if (err)
1802                         goto rollback;
1803         }
1804
1805         br_multicast_open(br);
1806         list_for_each_entry(port, &br->port_list, list) {
1807                 if (port->state == BR_STATE_DISABLED ||
1808                     port->state == BR_STATE_BLOCKING)
1809                         continue;
1810
1811                 __br_multicast_enable_port(port);
1812         }
1813
1814 unlock:
1815         spin_unlock_bh(&br->multicast_lock);
1816
1817         return err;
1818 }
1819
1820 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1821 {
1822         int err = -ENOENT;
1823         u32 old;
1824         struct net_bridge_mdb_htable *mdb;
1825
1826         spin_lock(&br->multicast_lock);
1827         if (!netif_running(br->dev))
1828                 goto unlock;
1829
1830         err = -EINVAL;
1831         if (!is_power_of_2(val))
1832                 goto unlock;
1833
1834         mdb = mlock_dereference(br->mdb, br);
1835         if (mdb && val < mdb->size)
1836                 goto unlock;
1837
1838         err = 0;
1839
1840         old = br->hash_max;
1841         br->hash_max = val;
1842
1843         if (mdb) {
1844                 if (mdb->old) {
1845                         err = -EEXIST;
1846 rollback:
1847                         br->hash_max = old;
1848                         goto unlock;
1849                 }
1850
1851                 err = br_mdb_rehash(&br->mdb, br->hash_max,
1852                                     br->hash_elasticity);
1853                 if (err)
1854                         goto rollback;
1855         }
1856
1857 unlock:
1858         spin_unlock(&br->multicast_lock);
1859
1860         return err;
1861 }