xref: /linux/net/bridge/br_multicast.c (revision 3f2fb9a834cb1fcddbae22deca7fde136944dc89)
1 /*
2  * Bridge multicast support.
3  *
4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/if_ether.h>
16 #include <linux/igmp.h>
17 #include <linux/jhash.h>
18 #include <linux/kernel.h>
19 #include <linux/log2.h>
20 #include <linux/netdevice.h>
21 #include <linux/netfilter_bridge.h>
22 #include <linux/random.h>
23 #include <linux/rculist.h>
24 #include <linux/skbuff.h>
25 #include <linux/slab.h>
26 #include <linux/timer.h>
27 #include <linux/inetdevice.h>
28 #include <net/ip.h>
29 #if IS_ENABLED(CONFIG_IPV6)
30 #include <net/ipv6.h>
31 #include <net/mld.h>
32 #include <net/ip6_checksum.h>
33 #include <net/addrconf.h>
34 #endif
35 
36 #include "br_private.h"
37 
38 static void br_multicast_start_querier(struct net_bridge *br,
39 				       struct bridge_mcast_own_query *query);
40 static void br_multicast_add_router(struct net_bridge *br,
41 				    struct net_bridge_port *port);
42 static void br_ip4_multicast_leave_group(struct net_bridge *br,
43 					 struct net_bridge_port *port,
44 					 __be32 group,
45 					 __u16 vid);
46 #if IS_ENABLED(CONFIG_IPV6)
47 static void br_ip6_multicast_leave_group(struct net_bridge *br,
48 					 struct net_bridge_port *port,
49 					 const struct in6_addr *group,
50 					 __u16 vid);
51 #endif
52 unsigned int br_mdb_rehash_seq;
53 
54 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
55 {
56 	if (a->proto != b->proto)
57 		return 0;
58 	if (a->vid != b->vid)
59 		return 0;
60 	switch (a->proto) {
61 	case htons(ETH_P_IP):
62 		return a->u.ip4 == b->u.ip4;
63 #if IS_ENABLED(CONFIG_IPV6)
64 	case htons(ETH_P_IPV6):
65 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
66 #endif
67 	}
68 	return 0;
69 }
70 
71 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
72 				__u16 vid)
73 {
74 	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
75 }
76 
77 #if IS_ENABLED(CONFIG_IPV6)
78 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
79 				const struct in6_addr *ip,
80 				__u16 vid)
81 {
82 	return jhash_2words(ipv6_addr_hash(ip), vid,
83 			    mdb->secret) & (mdb->max - 1);
84 }
85 #endif
86 
87 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
88 			     struct br_ip *ip)
89 {
90 	switch (ip->proto) {
91 	case htons(ETH_P_IP):
92 		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
93 #if IS_ENABLED(CONFIG_IPV6)
94 	case htons(ETH_P_IPV6):
95 		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
96 #endif
97 	}
98 	return 0;
99 }
100 
101 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
102 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
103 {
104 	struct net_bridge_mdb_entry *mp;
105 
106 	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
107 		if (br_ip_equal(&mp->addr, dst))
108 			return mp;
109 	}
110 
111 	return NULL;
112 }
113 
114 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
115 					   struct br_ip *dst)
116 {
117 	if (!mdb)
118 		return NULL;
119 
120 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
121 }
122 
123 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
124 	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
125 {
126 	struct br_ip br_dst;
127 
128 	br_dst.u.ip4 = dst;
129 	br_dst.proto = htons(ETH_P_IP);
130 	br_dst.vid = vid;
131 
132 	return br_mdb_ip_get(mdb, &br_dst);
133 }
134 
135 #if IS_ENABLED(CONFIG_IPV6)
136 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
137 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
138 	__u16 vid)
139 {
140 	struct br_ip br_dst;
141 
142 	br_dst.u.ip6 = *dst;
143 	br_dst.proto = htons(ETH_P_IPV6);
144 	br_dst.vid = vid;
145 
146 	return br_mdb_ip_get(mdb, &br_dst);
147 }
148 #endif
149 
150 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
151 					struct sk_buff *skb, u16 vid)
152 {
153 	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
154 	struct br_ip ip;
155 
156 	if (br->multicast_disabled)
157 		return NULL;
158 
159 	if (BR_INPUT_SKB_CB(skb)->igmp)
160 		return NULL;
161 
162 	ip.proto = skb->protocol;
163 	ip.vid = vid;
164 
165 	switch (skb->protocol) {
166 	case htons(ETH_P_IP):
167 		ip.u.ip4 = ip_hdr(skb)->daddr;
168 		break;
169 #if IS_ENABLED(CONFIG_IPV6)
170 	case htons(ETH_P_IPV6):
171 		ip.u.ip6 = ipv6_hdr(skb)->daddr;
172 		break;
173 #endif
174 	default:
175 		return NULL;
176 	}
177 
178 	return br_mdb_ip_get(mdb, &ip);
179 }
180 
181 static void br_mdb_free(struct rcu_head *head)
182 {
183 	struct net_bridge_mdb_htable *mdb =
184 		container_of(head, struct net_bridge_mdb_htable, rcu);
185 	struct net_bridge_mdb_htable *old = mdb->old;
186 
187 	mdb->old = NULL;
188 	kfree(old->mhash);
189 	kfree(old);
190 }
191 
192 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
193 		       struct net_bridge_mdb_htable *old,
194 		       int elasticity)
195 {
196 	struct net_bridge_mdb_entry *mp;
197 	int maxlen;
198 	int len;
199 	int i;
200 
201 	for (i = 0; i < old->max; i++)
202 		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
203 			hlist_add_head(&mp->hlist[new->ver],
204 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
205 
206 	if (!elasticity)
207 		return 0;
208 
209 	maxlen = 0;
210 	for (i = 0; i < new->max; i++) {
211 		len = 0;
212 		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
213 			len++;
214 		if (len > maxlen)
215 			maxlen = len;
216 	}
217 
218 	return maxlen > elasticity ? -EINVAL : 0;
219 }
220 
221 void br_multicast_free_pg(struct rcu_head *head)
222 {
223 	struct net_bridge_port_group *p =
224 		container_of(head, struct net_bridge_port_group, rcu);
225 
226 	kfree(p);
227 }
228 
229 static void br_multicast_free_group(struct rcu_head *head)
230 {
231 	struct net_bridge_mdb_entry *mp =
232 		container_of(head, struct net_bridge_mdb_entry, rcu);
233 
234 	kfree(mp);
235 }
236 
237 static void br_multicast_group_expired(unsigned long data)
238 {
239 	struct net_bridge_mdb_entry *mp = (void *)data;
240 	struct net_bridge *br = mp->br;
241 	struct net_bridge_mdb_htable *mdb;
242 
243 	spin_lock(&br->multicast_lock);
244 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
245 		goto out;
246 
247 	mp->mglist = false;
248 
249 	if (mp->ports)
250 		goto out;
251 
252 	mdb = mlock_dereference(br->mdb, br);
253 
254 	hlist_del_rcu(&mp->hlist[mdb->ver]);
255 	mdb->size--;
256 
257 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
258 
259 out:
260 	spin_unlock(&br->multicast_lock);
261 }
262 
263 static void br_multicast_del_pg(struct net_bridge *br,
264 				struct net_bridge_port_group *pg)
265 {
266 	struct net_bridge_mdb_htable *mdb;
267 	struct net_bridge_mdb_entry *mp;
268 	struct net_bridge_port_group *p;
269 	struct net_bridge_port_group __rcu **pp;
270 
271 	mdb = mlock_dereference(br->mdb, br);
272 
273 	mp = br_mdb_ip_get(mdb, &pg->addr);
274 	if (WARN_ON(!mp))
275 		return;
276 
277 	for (pp = &mp->ports;
278 	     (p = mlock_dereference(*pp, br)) != NULL;
279 	     pp = &p->next) {
280 		if (p != pg)
281 			continue;
282 
283 		rcu_assign_pointer(*pp, p->next);
284 		hlist_del_init(&p->mglist);
285 		del_timer(&p->timer);
286 		br_mdb_notify(br->dev, p, RTM_DELMDB);
287 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
288 
289 		if (!mp->ports && !mp->mglist &&
290 		    netif_running(br->dev))
291 			mod_timer(&mp->timer, jiffies);
292 
293 		return;
294 	}
295 
296 	WARN_ON(1);
297 }
298 
299 static void br_multicast_port_group_expired(unsigned long data)
300 {
301 	struct net_bridge_port_group *pg = (void *)data;
302 	struct net_bridge *br = pg->port->br;
303 
304 	spin_lock(&br->multicast_lock);
305 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
306 	    hlist_unhashed(&pg->mglist) || pg->flags & MDB_PG_FLAGS_PERMANENT)
307 		goto out;
308 
309 	br_multicast_del_pg(br, pg);
310 
311 out:
312 	spin_unlock(&br->multicast_lock);
313 }
314 
315 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
316 			 int elasticity)
317 {
318 	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
319 	struct net_bridge_mdb_htable *mdb;
320 	int err;
321 
322 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
323 	if (!mdb)
324 		return -ENOMEM;
325 
326 	mdb->max = max;
327 	mdb->old = old;
328 
329 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
330 	if (!mdb->mhash) {
331 		kfree(mdb);
332 		return -ENOMEM;
333 	}
334 
335 	mdb->size = old ? old->size : 0;
336 	mdb->ver = old ? old->ver ^ 1 : 0;
337 
338 	if (!old || elasticity)
339 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
340 	else
341 		mdb->secret = old->secret;
342 
343 	if (!old)
344 		goto out;
345 
346 	err = br_mdb_copy(mdb, old, elasticity);
347 	if (err) {
348 		kfree(mdb->mhash);
349 		kfree(mdb);
350 		return err;
351 	}
352 
353 	br_mdb_rehash_seq++;
354 	call_rcu_bh(&mdb->rcu, br_mdb_free);
355 
356 out:
357 	rcu_assign_pointer(*mdbp, mdb);
358 
359 	return 0;
360 }
361 
362 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
363 						    __be32 group)
364 {
365 	struct sk_buff *skb;
366 	struct igmphdr *ih;
367 	struct ethhdr *eth;
368 	struct iphdr *iph;
369 
370 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
371 						 sizeof(*ih) + 4);
372 	if (!skb)
373 		goto out;
374 
375 	skb->protocol = htons(ETH_P_IP);
376 
377 	skb_reset_mac_header(skb);
378 	eth = eth_hdr(skb);
379 
380 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
381 	eth->h_dest[0] = 1;
382 	eth->h_dest[1] = 0;
383 	eth->h_dest[2] = 0x5e;
384 	eth->h_dest[3] = 0;
385 	eth->h_dest[4] = 0;
386 	eth->h_dest[5] = 1;
387 	eth->h_proto = htons(ETH_P_IP);
388 	skb_put(skb, sizeof(*eth));
389 
390 	skb_set_network_header(skb, skb->len);
391 	iph = ip_hdr(skb);
392 
393 	iph->version = 4;
394 	iph->ihl = 6;
395 	iph->tos = 0xc0;
396 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
397 	iph->id = 0;
398 	iph->frag_off = htons(IP_DF);
399 	iph->ttl = 1;
400 	iph->protocol = IPPROTO_IGMP;
401 	iph->saddr = br->multicast_query_use_ifaddr ?
402 		     inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
403 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
404 	((u8 *)&iph[1])[0] = IPOPT_RA;
405 	((u8 *)&iph[1])[1] = 4;
406 	((u8 *)&iph[1])[2] = 0;
407 	((u8 *)&iph[1])[3] = 0;
408 	ip_send_check(iph);
409 	skb_put(skb, 24);
410 
411 	skb_set_transport_header(skb, skb->len);
412 	ih = igmp_hdr(skb);
413 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
414 	ih->code = (group ? br->multicast_last_member_interval :
415 			    br->multicast_query_response_interval) /
416 		   (HZ / IGMP_TIMER_SCALE);
417 	ih->group = group;
418 	ih->csum = 0;
419 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
420 	skb_put(skb, sizeof(*ih));
421 
422 	__skb_pull(skb, sizeof(*eth));
423 
424 out:
425 	return skb;
426 }
427 
428 #if IS_ENABLED(CONFIG_IPV6)
429 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
430 						    const struct in6_addr *group)
431 {
432 	struct sk_buff *skb;
433 	struct ipv6hdr *ip6h;
434 	struct mld_msg *mldq;
435 	struct ethhdr *eth;
436 	u8 *hopopt;
437 	unsigned long interval;
438 
439 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
440 						 8 + sizeof(*mldq));
441 	if (!skb)
442 		goto out;
443 
444 	skb->protocol = htons(ETH_P_IPV6);
445 
446 	/* Ethernet header */
447 	skb_reset_mac_header(skb);
448 	eth = eth_hdr(skb);
449 
450 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
451 	eth->h_proto = htons(ETH_P_IPV6);
452 	skb_put(skb, sizeof(*eth));
453 
454 	/* IPv6 header + HbH option */
455 	skb_set_network_header(skb, skb->len);
456 	ip6h = ipv6_hdr(skb);
457 
458 	*(__force __be32 *)ip6h = htonl(0x60000000);
459 	ip6h->payload_len = htons(8 + sizeof(*mldq));
460 	ip6h->nexthdr = IPPROTO_HOPOPTS;
461 	ip6h->hop_limit = 1;
462 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
463 	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
464 			       &ip6h->saddr)) {
465 		kfree_skb(skb);
466 		return NULL;
467 	}
468 	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
469 
470 	hopopt = (u8 *)(ip6h + 1);
471 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
472 	hopopt[1] = 0;				/* length of HbH */
473 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
474 	hopopt[3] = 2;				/* Length of RA Option */
475 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
476 	hopopt[5] = 0;
477 	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
478 	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
479 
480 	skb_put(skb, sizeof(*ip6h) + 8);
481 
482 	/* ICMPv6 */
483 	skb_set_transport_header(skb, skb->len);
484 	mldq = (struct mld_msg *) icmp6_hdr(skb);
485 
486 	interval = ipv6_addr_any(group) ?
487 			br->multicast_query_response_interval :
488 			br->multicast_last_member_interval;
489 
490 	mldq->mld_type = ICMPV6_MGM_QUERY;
491 	mldq->mld_code = 0;
492 	mldq->mld_cksum = 0;
493 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
494 	mldq->mld_reserved = 0;
495 	mldq->mld_mca = *group;
496 
497 	/* checksum */
498 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
499 					  sizeof(*mldq), IPPROTO_ICMPV6,
500 					  csum_partial(mldq,
501 						       sizeof(*mldq), 0));
502 	skb_put(skb, sizeof(*mldq));
503 
504 	__skb_pull(skb, sizeof(*eth));
505 
506 out:
507 	return skb;
508 }
509 #endif
510 
511 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
512 						struct br_ip *addr)
513 {
514 	switch (addr->proto) {
515 	case htons(ETH_P_IP):
516 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
517 #if IS_ENABLED(CONFIG_IPV6)
518 	case htons(ETH_P_IPV6):
519 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
520 #endif
521 	}
522 	return NULL;
523 }
524 
525 static struct net_bridge_mdb_entry *br_multicast_get_group(
526 	struct net_bridge *br, struct net_bridge_port *port,
527 	struct br_ip *group, int hash)
528 {
529 	struct net_bridge_mdb_htable *mdb;
530 	struct net_bridge_mdb_entry *mp;
531 	unsigned int count = 0;
532 	unsigned int max;
533 	int elasticity;
534 	int err;
535 
536 	mdb = rcu_dereference_protected(br->mdb, 1);
537 	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
538 		count++;
539 		if (unlikely(br_ip_equal(group, &mp->addr)))
540 			return mp;
541 	}
542 
543 	elasticity = 0;
544 	max = mdb->max;
545 
546 	if (unlikely(count > br->hash_elasticity && count)) {
547 		if (net_ratelimit())
548 			br_info(br, "Multicast hash table "
549 				"chain limit reached: %s\n",
550 				port ? port->dev->name : br->dev->name);
551 
552 		elasticity = br->hash_elasticity;
553 	}
554 
555 	if (mdb->size >= max) {
556 		max *= 2;
557 		if (unlikely(max > br->hash_max)) {
558 			br_warn(br, "Multicast hash table maximum of %d "
559 				"reached, disabling snooping: %s\n",
560 				br->hash_max,
561 				port ? port->dev->name : br->dev->name);
562 			err = -E2BIG;
563 disable:
564 			br->multicast_disabled = 1;
565 			goto err;
566 		}
567 	}
568 
569 	if (max > mdb->max || elasticity) {
570 		if (mdb->old) {
571 			if (net_ratelimit())
572 				br_info(br, "Multicast hash table "
573 					"on fire: %s\n",
574 					port ? port->dev->name : br->dev->name);
575 			err = -EEXIST;
576 			goto err;
577 		}
578 
579 		err = br_mdb_rehash(&br->mdb, max, elasticity);
580 		if (err) {
581 			br_warn(br, "Cannot rehash multicast "
582 				"hash table, disabling snooping: %s, %d, %d\n",
583 				port ? port->dev->name : br->dev->name,
584 				mdb->size, err);
585 			goto disable;
586 		}
587 
588 		err = -EAGAIN;
589 		goto err;
590 	}
591 
592 	return NULL;
593 
594 err:
595 	mp = ERR_PTR(err);
596 	return mp;
597 }
598 
599 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
600 	struct net_bridge_port *port, struct br_ip *group)
601 {
602 	struct net_bridge_mdb_htable *mdb;
603 	struct net_bridge_mdb_entry *mp;
604 	int hash;
605 	int err;
606 
607 	mdb = rcu_dereference_protected(br->mdb, 1);
608 	if (!mdb) {
609 		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
610 		if (err)
611 			return ERR_PTR(err);
612 		goto rehash;
613 	}
614 
615 	hash = br_ip_hash(mdb, group);
616 	mp = br_multicast_get_group(br, port, group, hash);
617 	switch (PTR_ERR(mp)) {
618 	case 0:
619 		break;
620 
621 	case -EAGAIN:
622 rehash:
623 		mdb = rcu_dereference_protected(br->mdb, 1);
624 		hash = br_ip_hash(mdb, group);
625 		break;
626 
627 	default:
628 		goto out;
629 	}
630 
631 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
632 	if (unlikely(!mp))
633 		return ERR_PTR(-ENOMEM);
634 
635 	mp->br = br;
636 	mp->addr = *group;
637 	setup_timer(&mp->timer, br_multicast_group_expired,
638 		    (unsigned long)mp);
639 
640 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
641 	mdb->size++;
642 
643 out:
644 	return mp;
645 }
646 
647 struct net_bridge_port_group *br_multicast_new_port_group(
648 			struct net_bridge_port *port,
649 			struct br_ip *group,
650 			struct net_bridge_port_group __rcu *next,
651 			unsigned char flags)
652 {
653 	struct net_bridge_port_group *p;
654 
655 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
656 	if (unlikely(!p))
657 		return NULL;
658 
659 	p->addr = *group;
660 	p->port = port;
661 	p->flags = flags;
662 	rcu_assign_pointer(p->next, next);
663 	hlist_add_head(&p->mglist, &port->mglist);
664 	setup_timer(&p->timer, br_multicast_port_group_expired,
665 		    (unsigned long)p);
666 	return p;
667 }
668 
669 static int br_multicast_add_group(struct net_bridge *br,
670 				  struct net_bridge_port *port,
671 				  struct br_ip *group)
672 {
673 	struct net_bridge_mdb_entry *mp;
674 	struct net_bridge_port_group *p;
675 	struct net_bridge_port_group __rcu **pp;
676 	unsigned long now = jiffies;
677 	int err;
678 
679 	spin_lock(&br->multicast_lock);
680 	if (!netif_running(br->dev) ||
681 	    (port && port->state == BR_STATE_DISABLED))
682 		goto out;
683 
684 	mp = br_multicast_new_group(br, port, group);
685 	err = PTR_ERR(mp);
686 	if (IS_ERR(mp))
687 		goto err;
688 
689 	if (!port) {
690 		mp->mglist = true;
691 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
692 		goto out;
693 	}
694 
695 	for (pp = &mp->ports;
696 	     (p = mlock_dereference(*pp, br)) != NULL;
697 	     pp = &p->next) {
698 		if (p->port == port)
699 			goto found;
700 		if ((unsigned long)p->port < (unsigned long)port)
701 			break;
702 	}
703 
704 	p = br_multicast_new_port_group(port, group, *pp, 0);
705 	if (unlikely(!p))
706 		goto err;
707 	rcu_assign_pointer(*pp, p);
708 	br_mdb_notify(br->dev, p, RTM_NEWMDB);
709 
710 found:
711 	mod_timer(&p->timer, now + br->multicast_membership_interval);
712 out:
713 	err = 0;
714 
715 err:
716 	spin_unlock(&br->multicast_lock);
717 	return err;
718 }
719 
720 static int br_ip4_multicast_add_group(struct net_bridge *br,
721 				      struct net_bridge_port *port,
722 				      __be32 group,
723 				      __u16 vid)
724 {
725 	struct br_ip br_group;
726 
727 	if (ipv4_is_local_multicast(group))
728 		return 0;
729 
730 	br_group.u.ip4 = group;
731 	br_group.proto = htons(ETH_P_IP);
732 	br_group.vid = vid;
733 
734 	return br_multicast_add_group(br, port, &br_group);
735 }
736 
737 #if IS_ENABLED(CONFIG_IPV6)
738 static int br_ip6_multicast_add_group(struct net_bridge *br,
739 				      struct net_bridge_port *port,
740 				      const struct in6_addr *group,
741 				      __u16 vid)
742 {
743 	struct br_ip br_group;
744 
745 	if (ipv6_addr_is_ll_all_nodes(group))
746 		return 0;
747 
748 	br_group.u.ip6 = *group;
749 	br_group.proto = htons(ETH_P_IPV6);
750 	br_group.vid = vid;
751 
752 	return br_multicast_add_group(br, port, &br_group);
753 }
754 #endif
755 
756 static void br_multicast_router_expired(unsigned long data)
757 {
758 	struct net_bridge_port *port = (void *)data;
759 	struct net_bridge *br = port->br;
760 
761 	spin_lock(&br->multicast_lock);
762 	if (port->multicast_router != 1 ||
763 	    timer_pending(&port->multicast_router_timer) ||
764 	    hlist_unhashed(&port->rlist))
765 		goto out;
766 
767 	hlist_del_init_rcu(&port->rlist);
768 	br_rtr_notify(br->dev, port, RTM_DELMDB);
769 
770 out:
771 	spin_unlock(&br->multicast_lock);
772 }
773 
774 static void br_multicast_local_router_expired(unsigned long data)
775 {
776 }
777 
778 static void br_multicast_querier_expired(struct net_bridge *br,
779 					 struct bridge_mcast_own_query *query)
780 {
781 	spin_lock(&br->multicast_lock);
782 	if (!netif_running(br->dev) || br->multicast_disabled)
783 		goto out;
784 
785 	br_multicast_start_querier(br, query);
786 
787 out:
788 	spin_unlock(&br->multicast_lock);
789 }
790 
791 static void br_ip4_multicast_querier_expired(unsigned long data)
792 {
793 	struct net_bridge *br = (void *)data;
794 
795 	br_multicast_querier_expired(br, &br->ip4_own_query);
796 }
797 
798 #if IS_ENABLED(CONFIG_IPV6)
799 static void br_ip6_multicast_querier_expired(unsigned long data)
800 {
801 	struct net_bridge *br = (void *)data;
802 
803 	br_multicast_querier_expired(br, &br->ip6_own_query);
804 }
805 #endif
806 
807 static void br_multicast_select_own_querier(struct net_bridge *br,
808 					    struct br_ip *ip,
809 					    struct sk_buff *skb)
810 {
811 	if (ip->proto == htons(ETH_P_IP))
812 		br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
813 #if IS_ENABLED(CONFIG_IPV6)
814 	else
815 		br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
816 #endif
817 }
818 
819 static void __br_multicast_send_query(struct net_bridge *br,
820 				      struct net_bridge_port *port,
821 				      struct br_ip *ip)
822 {
823 	struct sk_buff *skb;
824 
825 	skb = br_multicast_alloc_query(br, ip);
826 	if (!skb)
827 		return;
828 
829 	if (port) {
830 		skb->dev = port->dev;
831 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
832 			dev_net(port->dev), NULL, skb, NULL, skb->dev,
833 			br_dev_queue_push_xmit);
834 	} else {
835 		br_multicast_select_own_querier(br, ip, skb);
836 		netif_rx(skb);
837 	}
838 }
839 
840 static void br_multicast_send_query(struct net_bridge *br,
841 				    struct net_bridge_port *port,
842 				    struct bridge_mcast_own_query *own_query)
843 {
844 	unsigned long time;
845 	struct br_ip br_group;
846 	struct bridge_mcast_other_query *other_query = NULL;
847 
848 	if (!netif_running(br->dev) || br->multicast_disabled ||
849 	    !br->multicast_querier)
850 		return;
851 
852 	memset(&br_group.u, 0, sizeof(br_group.u));
853 
854 	if (port ? (own_query == &port->ip4_own_query) :
855 		   (own_query == &br->ip4_own_query)) {
856 		other_query = &br->ip4_other_query;
857 		br_group.proto = htons(ETH_P_IP);
858 #if IS_ENABLED(CONFIG_IPV6)
859 	} else {
860 		other_query = &br->ip6_other_query;
861 		br_group.proto = htons(ETH_P_IPV6);
862 #endif
863 	}
864 
865 	if (!other_query || timer_pending(&other_query->timer))
866 		return;
867 
868 	__br_multicast_send_query(br, port, &br_group);
869 
870 	time = jiffies;
871 	time += own_query->startup_sent < br->multicast_startup_query_count ?
872 		br->multicast_startup_query_interval :
873 		br->multicast_query_interval;
874 	mod_timer(&own_query->timer, time);
875 }
876 
877 static void
878 br_multicast_port_query_expired(struct net_bridge_port *port,
879 				struct bridge_mcast_own_query *query)
880 {
881 	struct net_bridge *br = port->br;
882 
883 	spin_lock(&br->multicast_lock);
884 	if (port->state == BR_STATE_DISABLED ||
885 	    port->state == BR_STATE_BLOCKING)
886 		goto out;
887 
888 	if (query->startup_sent < br->multicast_startup_query_count)
889 		query->startup_sent++;
890 
891 	br_multicast_send_query(port->br, port, query);
892 
893 out:
894 	spin_unlock(&br->multicast_lock);
895 }
896 
897 static void br_ip4_multicast_port_query_expired(unsigned long data)
898 {
899 	struct net_bridge_port *port = (void *)data;
900 
901 	br_multicast_port_query_expired(port, &port->ip4_own_query);
902 }
903 
904 #if IS_ENABLED(CONFIG_IPV6)
905 static void br_ip6_multicast_port_query_expired(unsigned long data)
906 {
907 	struct net_bridge_port *port = (void *)data;
908 
909 	br_multicast_port_query_expired(port, &port->ip6_own_query);
910 }
911 #endif
912 
913 void br_multicast_add_port(struct net_bridge_port *port)
914 {
915 	port->multicast_router = 1;
916 
917 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
918 		    (unsigned long)port);
919 	setup_timer(&port->ip4_own_query.timer,
920 		    br_ip4_multicast_port_query_expired, (unsigned long)port);
921 #if IS_ENABLED(CONFIG_IPV6)
922 	setup_timer(&port->ip6_own_query.timer,
923 		    br_ip6_multicast_port_query_expired, (unsigned long)port);
924 #endif
925 }
926 
927 void br_multicast_del_port(struct net_bridge_port *port)
928 {
929 	struct net_bridge *br = port->br;
930 	struct net_bridge_port_group *pg;
931 	struct hlist_node *n;
932 
933 	/* Take care of the remaining groups, only perm ones should be left */
934 	spin_lock_bh(&br->multicast_lock);
935 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
936 		br_multicast_del_pg(br, pg);
937 	spin_unlock_bh(&br->multicast_lock);
938 	del_timer_sync(&port->multicast_router_timer);
939 }
940 
941 static void br_multicast_enable(struct bridge_mcast_own_query *query)
942 {
943 	query->startup_sent = 0;
944 
945 	if (try_to_del_timer_sync(&query->timer) >= 0 ||
946 	    del_timer(&query->timer))
947 		mod_timer(&query->timer, jiffies);
948 }
949 
950 void br_multicast_enable_port(struct net_bridge_port *port)
951 {
952 	struct net_bridge *br = port->br;
953 
954 	spin_lock(&br->multicast_lock);
955 	if (br->multicast_disabled || !netif_running(br->dev))
956 		goto out;
957 
958 	br_multicast_enable(&port->ip4_own_query);
959 #if IS_ENABLED(CONFIG_IPV6)
960 	br_multicast_enable(&port->ip6_own_query);
961 #endif
962 	if (port->multicast_router == 2 && hlist_unhashed(&port->rlist))
963 		br_multicast_add_router(br, port);
964 
965 out:
966 	spin_unlock(&br->multicast_lock);
967 }
968 
969 void br_multicast_disable_port(struct net_bridge_port *port)
970 {
971 	struct net_bridge *br = port->br;
972 	struct net_bridge_port_group *pg;
973 	struct hlist_node *n;
974 
975 	spin_lock(&br->multicast_lock);
976 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
977 		if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
978 			br_multicast_del_pg(br, pg);
979 
980 	if (!hlist_unhashed(&port->rlist)) {
981 		hlist_del_init_rcu(&port->rlist);
982 		br_rtr_notify(br->dev, port, RTM_DELMDB);
983 	}
984 	del_timer(&port->multicast_router_timer);
985 	del_timer(&port->ip4_own_query.timer);
986 #if IS_ENABLED(CONFIG_IPV6)
987 	del_timer(&port->ip6_own_query.timer);
988 #endif
989 	spin_unlock(&br->multicast_lock);
990 }
991 
992 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
993 					 struct net_bridge_port *port,
994 					 struct sk_buff *skb,
995 					 u16 vid)
996 {
997 	struct igmpv3_report *ih;
998 	struct igmpv3_grec *grec;
999 	int i;
1000 	int len;
1001 	int num;
1002 	int type;
1003 	int err = 0;
1004 	__be32 group;
1005 
1006 	ih = igmpv3_report_hdr(skb);
1007 	num = ntohs(ih->ngrec);
1008 	len = skb_transport_offset(skb) + sizeof(*ih);
1009 
1010 	for (i = 0; i < num; i++) {
1011 		len += sizeof(*grec);
1012 		if (!pskb_may_pull(skb, len))
1013 			return -EINVAL;
1014 
1015 		grec = (void *)(skb->data + len - sizeof(*grec));
1016 		group = grec->grec_mca;
1017 		type = grec->grec_type;
1018 
1019 		len += ntohs(grec->grec_nsrcs) * 4;
1020 		if (!pskb_may_pull(skb, len))
1021 			return -EINVAL;
1022 
1023 		/* We treat this as an IGMPv2 report for now. */
1024 		switch (type) {
1025 		case IGMPV3_MODE_IS_INCLUDE:
1026 		case IGMPV3_MODE_IS_EXCLUDE:
1027 		case IGMPV3_CHANGE_TO_INCLUDE:
1028 		case IGMPV3_CHANGE_TO_EXCLUDE:
1029 		case IGMPV3_ALLOW_NEW_SOURCES:
1030 		case IGMPV3_BLOCK_OLD_SOURCES:
1031 			break;
1032 
1033 		default:
1034 			continue;
1035 		}
1036 
1037 		if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
1038 		     type == IGMPV3_MODE_IS_INCLUDE) &&
1039 		    ntohs(grec->grec_nsrcs) == 0) {
1040 			br_ip4_multicast_leave_group(br, port, group, vid);
1041 		} else {
1042 			err = br_ip4_multicast_add_group(br, port, group, vid);
1043 			if (err)
1044 				break;
1045 		}
1046 	}
1047 
1048 	return err;
1049 }
1050 
1051 #if IS_ENABLED(CONFIG_IPV6)
1052 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1053 					struct net_bridge_port *port,
1054 					struct sk_buff *skb,
1055 					u16 vid)
1056 {
1057 	struct icmp6hdr *icmp6h;
1058 	struct mld2_grec *grec;
1059 	int i;
1060 	int len;
1061 	int num;
1062 	int err = 0;
1063 
1064 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1065 		return -EINVAL;
1066 
1067 	icmp6h = icmp6_hdr(skb);
1068 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1069 	len = skb_transport_offset(skb) + sizeof(*icmp6h);
1070 
1071 	for (i = 0; i < num; i++) {
1072 		__be16 *nsrcs, _nsrcs;
1073 
1074 		nsrcs = skb_header_pointer(skb,
1075 					   len + offsetof(struct mld2_grec,
1076 							  grec_nsrcs),
1077 					   sizeof(_nsrcs), &_nsrcs);
1078 		if (!nsrcs)
1079 			return -EINVAL;
1080 
1081 		if (!pskb_may_pull(skb,
1082 				   len + sizeof(*grec) +
1083 				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
1084 			return -EINVAL;
1085 
1086 		grec = (struct mld2_grec *)(skb->data + len);
1087 		len += sizeof(*grec) +
1088 		       sizeof(struct in6_addr) * ntohs(*nsrcs);
1089 
1090 		/* We treat these as MLDv1 reports for now. */
1091 		switch (grec->grec_type) {
1092 		case MLD2_MODE_IS_INCLUDE:
1093 		case MLD2_MODE_IS_EXCLUDE:
1094 		case MLD2_CHANGE_TO_INCLUDE:
1095 		case MLD2_CHANGE_TO_EXCLUDE:
1096 		case MLD2_ALLOW_NEW_SOURCES:
1097 		case MLD2_BLOCK_OLD_SOURCES:
1098 			break;
1099 
1100 		default:
1101 			continue;
1102 		}
1103 
1104 		if ((grec->grec_type == MLD2_CHANGE_TO_INCLUDE ||
1105 		     grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
1106 		    ntohs(*nsrcs) == 0) {
1107 			br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
1108 						     vid);
1109 		} else {
1110 			err = br_ip6_multicast_add_group(br, port,
1111 							 &grec->grec_mca, vid);
1112 			if (!err)
1113 				break;
1114 		}
1115 	}
1116 
1117 	return err;
1118 }
1119 #endif
1120 
1121 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1122 					    struct net_bridge_port *port,
1123 					    __be32 saddr)
1124 {
1125 	if (!timer_pending(&br->ip4_own_query.timer) &&
1126 	    !timer_pending(&br->ip4_other_query.timer))
1127 		goto update;
1128 
1129 	if (!br->ip4_querier.addr.u.ip4)
1130 		goto update;
1131 
1132 	if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1133 		goto update;
1134 
1135 	return false;
1136 
1137 update:
1138 	br->ip4_querier.addr.u.ip4 = saddr;
1139 
1140 	/* update protected by general multicast_lock by caller */
1141 	rcu_assign_pointer(br->ip4_querier.port, port);
1142 
1143 	return true;
1144 }
1145 
1146 #if IS_ENABLED(CONFIG_IPV6)
1147 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1148 					    struct net_bridge_port *port,
1149 					    struct in6_addr *saddr)
1150 {
1151 	if (!timer_pending(&br->ip6_own_query.timer) &&
1152 	    !timer_pending(&br->ip6_other_query.timer))
1153 		goto update;
1154 
1155 	if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1156 		goto update;
1157 
1158 	return false;
1159 
1160 update:
1161 	br->ip6_querier.addr.u.ip6 = *saddr;
1162 
1163 	/* update protected by general multicast_lock by caller */
1164 	rcu_assign_pointer(br->ip6_querier.port, port);
1165 
1166 	return true;
1167 }
1168 #endif
1169 
1170 static bool br_multicast_select_querier(struct net_bridge *br,
1171 					struct net_bridge_port *port,
1172 					struct br_ip *saddr)
1173 {
1174 	switch (saddr->proto) {
1175 	case htons(ETH_P_IP):
1176 		return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1177 #if IS_ENABLED(CONFIG_IPV6)
1178 	case htons(ETH_P_IPV6):
1179 		return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1180 #endif
1181 	}
1182 
1183 	return false;
1184 }
1185 
1186 static void
1187 br_multicast_update_query_timer(struct net_bridge *br,
1188 				struct bridge_mcast_other_query *query,
1189 				unsigned long max_delay)
1190 {
1191 	if (!timer_pending(&query->timer))
1192 		query->delay_time = jiffies + max_delay;
1193 
1194 	mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1195 }
1196 
1197 /*
1198  * Add port to router_list
1199  *  list is maintained ordered by pointer value
1200  *  and locked by br->multicast_lock and RCU
1201  */
1202 static void br_multicast_add_router(struct net_bridge *br,
1203 				    struct net_bridge_port *port)
1204 {
1205 	struct net_bridge_port *p;
1206 	struct hlist_node *slot = NULL;
1207 
1208 	if (!hlist_unhashed(&port->rlist))
1209 		return;
1210 
1211 	hlist_for_each_entry(p, &br->router_list, rlist) {
1212 		if ((unsigned long) port >= (unsigned long) p)
1213 			break;
1214 		slot = &p->rlist;
1215 	}
1216 
1217 	if (slot)
1218 		hlist_add_behind_rcu(&port->rlist, slot);
1219 	else
1220 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1221 	br_rtr_notify(br->dev, port, RTM_NEWMDB);
1222 }
1223 
1224 static void br_multicast_mark_router(struct net_bridge *br,
1225 				     struct net_bridge_port *port)
1226 {
1227 	unsigned long now = jiffies;
1228 
1229 	if (!port) {
1230 		if (br->multicast_router == 1)
1231 			mod_timer(&br->multicast_router_timer,
1232 				  now + br->multicast_querier_interval);
1233 		return;
1234 	}
1235 
1236 	if (port->multicast_router != 1)
1237 		return;
1238 
1239 	br_multicast_add_router(br, port);
1240 
1241 	mod_timer(&port->multicast_router_timer,
1242 		  now + br->multicast_querier_interval);
1243 }
1244 
1245 static void br_multicast_query_received(struct net_bridge *br,
1246 					struct net_bridge_port *port,
1247 					struct bridge_mcast_other_query *query,
1248 					struct br_ip *saddr,
1249 					unsigned long max_delay)
1250 {
1251 	if (!br_multicast_select_querier(br, port, saddr))
1252 		return;
1253 
1254 	br_multicast_update_query_timer(br, query, max_delay);
1255 	br_multicast_mark_router(br, port);
1256 }
1257 
1258 static int br_ip4_multicast_query(struct net_bridge *br,
1259 				  struct net_bridge_port *port,
1260 				  struct sk_buff *skb,
1261 				  u16 vid)
1262 {
1263 	const struct iphdr *iph = ip_hdr(skb);
1264 	struct igmphdr *ih = igmp_hdr(skb);
1265 	struct net_bridge_mdb_entry *mp;
1266 	struct igmpv3_query *ih3;
1267 	struct net_bridge_port_group *p;
1268 	struct net_bridge_port_group __rcu **pp;
1269 	struct br_ip saddr;
1270 	unsigned long max_delay;
1271 	unsigned long now = jiffies;
1272 	__be32 group;
1273 	int err = 0;
1274 
1275 	spin_lock(&br->multicast_lock);
1276 	if (!netif_running(br->dev) ||
1277 	    (port && port->state == BR_STATE_DISABLED))
1278 		goto out;
1279 
1280 	group = ih->group;
1281 
1282 	if (skb->len == sizeof(*ih)) {
1283 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1284 
1285 		if (!max_delay) {
1286 			max_delay = 10 * HZ;
1287 			group = 0;
1288 		}
1289 	} else if (skb->len >= sizeof(*ih3)) {
1290 		ih3 = igmpv3_query_hdr(skb);
1291 		if (ih3->nsrcs)
1292 			goto out;
1293 
1294 		max_delay = ih3->code ?
1295 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1296 	} else {
1297 		goto out;
1298 	}
1299 
1300 	if (!group) {
1301 		saddr.proto = htons(ETH_P_IP);
1302 		saddr.u.ip4 = iph->saddr;
1303 
1304 		br_multicast_query_received(br, port, &br->ip4_other_query,
1305 					    &saddr, max_delay);
1306 		goto out;
1307 	}
1308 
1309 	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1310 	if (!mp)
1311 		goto out;
1312 
1313 	max_delay *= br->multicast_last_member_count;
1314 
1315 	if (mp->mglist &&
1316 	    (timer_pending(&mp->timer) ?
1317 	     time_after(mp->timer.expires, now + max_delay) :
1318 	     try_to_del_timer_sync(&mp->timer) >= 0))
1319 		mod_timer(&mp->timer, now + max_delay);
1320 
1321 	for (pp = &mp->ports;
1322 	     (p = mlock_dereference(*pp, br)) != NULL;
1323 	     pp = &p->next) {
1324 		if (timer_pending(&p->timer) ?
1325 		    time_after(p->timer.expires, now + max_delay) :
1326 		    try_to_del_timer_sync(&p->timer) >= 0)
1327 			mod_timer(&p->timer, now + max_delay);
1328 	}
1329 
1330 out:
1331 	spin_unlock(&br->multicast_lock);
1332 	return err;
1333 }
1334 
1335 #if IS_ENABLED(CONFIG_IPV6)
1336 static int br_ip6_multicast_query(struct net_bridge *br,
1337 				  struct net_bridge_port *port,
1338 				  struct sk_buff *skb,
1339 				  u16 vid)
1340 {
1341 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1342 	struct mld_msg *mld;
1343 	struct net_bridge_mdb_entry *mp;
1344 	struct mld2_query *mld2q;
1345 	struct net_bridge_port_group *p;
1346 	struct net_bridge_port_group __rcu **pp;
1347 	struct br_ip saddr;
1348 	unsigned long max_delay;
1349 	unsigned long now = jiffies;
1350 	const struct in6_addr *group = NULL;
1351 	bool is_general_query;
1352 	int err = 0;
1353 
1354 	spin_lock(&br->multicast_lock);
1355 	if (!netif_running(br->dev) ||
1356 	    (port && port->state == BR_STATE_DISABLED))
1357 		goto out;
1358 
1359 	if (skb->len == sizeof(*mld)) {
1360 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1361 			err = -EINVAL;
1362 			goto out;
1363 		}
1364 		mld = (struct mld_msg *) icmp6_hdr(skb);
1365 		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1366 		if (max_delay)
1367 			group = &mld->mld_mca;
1368 	} else {
1369 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1370 			err = -EINVAL;
1371 			goto out;
1372 		}
1373 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1374 		if (!mld2q->mld2q_nsrcs)
1375 			group = &mld2q->mld2q_mca;
1376 
1377 		max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1378 	}
1379 
1380 	is_general_query = group && ipv6_addr_any(group);
1381 
1382 	if (is_general_query) {
1383 		saddr.proto = htons(ETH_P_IPV6);
1384 		saddr.u.ip6 = ip6h->saddr;
1385 
1386 		br_multicast_query_received(br, port, &br->ip6_other_query,
1387 					    &saddr, max_delay);
1388 		goto out;
1389 	} else if (!group) {
1390 		goto out;
1391 	}
1392 
1393 	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1394 	if (!mp)
1395 		goto out;
1396 
1397 	max_delay *= br->multicast_last_member_count;
1398 	if (mp->mglist &&
1399 	    (timer_pending(&mp->timer) ?
1400 	     time_after(mp->timer.expires, now + max_delay) :
1401 	     try_to_del_timer_sync(&mp->timer) >= 0))
1402 		mod_timer(&mp->timer, now + max_delay);
1403 
1404 	for (pp = &mp->ports;
1405 	     (p = mlock_dereference(*pp, br)) != NULL;
1406 	     pp = &p->next) {
1407 		if (timer_pending(&p->timer) ?
1408 		    time_after(p->timer.expires, now + max_delay) :
1409 		    try_to_del_timer_sync(&p->timer) >= 0)
1410 			mod_timer(&p->timer, now + max_delay);
1411 	}
1412 
1413 out:
1414 	spin_unlock(&br->multicast_lock);
1415 	return err;
1416 }
1417 #endif
1418 
1419 static void
1420 br_multicast_leave_group(struct net_bridge *br,
1421 			 struct net_bridge_port *port,
1422 			 struct br_ip *group,
1423 			 struct bridge_mcast_other_query *other_query,
1424 			 struct bridge_mcast_own_query *own_query)
1425 {
1426 	struct net_bridge_mdb_htable *mdb;
1427 	struct net_bridge_mdb_entry *mp;
1428 	struct net_bridge_port_group *p;
1429 	unsigned long now;
1430 	unsigned long time;
1431 
1432 	spin_lock(&br->multicast_lock);
1433 	if (!netif_running(br->dev) ||
1434 	    (port && port->state == BR_STATE_DISABLED))
1435 		goto out;
1436 
1437 	mdb = mlock_dereference(br->mdb, br);
1438 	mp = br_mdb_ip_get(mdb, group);
1439 	if (!mp)
1440 		goto out;
1441 
1442 	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1443 		struct net_bridge_port_group __rcu **pp;
1444 
1445 		for (pp = &mp->ports;
1446 		     (p = mlock_dereference(*pp, br)) != NULL;
1447 		     pp = &p->next) {
1448 			if (p->port != port)
1449 				continue;
1450 
1451 			rcu_assign_pointer(*pp, p->next);
1452 			hlist_del_init(&p->mglist);
1453 			del_timer(&p->timer);
1454 			call_rcu_bh(&p->rcu, br_multicast_free_pg);
1455 			br_mdb_notify(br->dev, p, RTM_DELMDB);
1456 
1457 			if (!mp->ports && !mp->mglist &&
1458 			    netif_running(br->dev))
1459 				mod_timer(&mp->timer, jiffies);
1460 		}
1461 		goto out;
1462 	}
1463 
1464 	if (timer_pending(&other_query->timer))
1465 		goto out;
1466 
1467 	if (br->multicast_querier) {
1468 		__br_multicast_send_query(br, port, &mp->addr);
1469 
1470 		time = jiffies + br->multicast_last_member_count *
1471 				 br->multicast_last_member_interval;
1472 
1473 		mod_timer(&own_query->timer, time);
1474 
1475 		for (p = mlock_dereference(mp->ports, br);
1476 		     p != NULL;
1477 		     p = mlock_dereference(p->next, br)) {
1478 			if (p->port != port)
1479 				continue;
1480 
1481 			if (!hlist_unhashed(&p->mglist) &&
1482 			    (timer_pending(&p->timer) ?
1483 			     time_after(p->timer.expires, time) :
1484 			     try_to_del_timer_sync(&p->timer) >= 0)) {
1485 				mod_timer(&p->timer, time);
1486 			}
1487 
1488 			break;
1489 		}
1490 	}
1491 
1492 	now = jiffies;
1493 	time = now + br->multicast_last_member_count *
1494 		     br->multicast_last_member_interval;
1495 
1496 	if (!port) {
1497 		if (mp->mglist &&
1498 		    (timer_pending(&mp->timer) ?
1499 		     time_after(mp->timer.expires, time) :
1500 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1501 			mod_timer(&mp->timer, time);
1502 		}
1503 
1504 		goto out;
1505 	}
1506 
1507 	for (p = mlock_dereference(mp->ports, br);
1508 	     p != NULL;
1509 	     p = mlock_dereference(p->next, br)) {
1510 		if (p->port != port)
1511 			continue;
1512 
1513 		if (!hlist_unhashed(&p->mglist) &&
1514 		    (timer_pending(&p->timer) ?
1515 		     time_after(p->timer.expires, time) :
1516 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1517 			mod_timer(&p->timer, time);
1518 		}
1519 
1520 		break;
1521 	}
1522 out:
1523 	spin_unlock(&br->multicast_lock);
1524 }
1525 
1526 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1527 					 struct net_bridge_port *port,
1528 					 __be32 group,
1529 					 __u16 vid)
1530 {
1531 	struct br_ip br_group;
1532 	struct bridge_mcast_own_query *own_query;
1533 
1534 	if (ipv4_is_local_multicast(group))
1535 		return;
1536 
1537 	own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1538 
1539 	br_group.u.ip4 = group;
1540 	br_group.proto = htons(ETH_P_IP);
1541 	br_group.vid = vid;
1542 
1543 	br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1544 				 own_query);
1545 }
1546 
1547 #if IS_ENABLED(CONFIG_IPV6)
1548 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1549 					 struct net_bridge_port *port,
1550 					 const struct in6_addr *group,
1551 					 __u16 vid)
1552 {
1553 	struct br_ip br_group;
1554 	struct bridge_mcast_own_query *own_query;
1555 
1556 	if (ipv6_addr_is_ll_all_nodes(group))
1557 		return;
1558 
1559 	own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1560 
1561 	br_group.u.ip6 = *group;
1562 	br_group.proto = htons(ETH_P_IPV6);
1563 	br_group.vid = vid;
1564 
1565 	br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1566 				 own_query);
1567 }
1568 #endif
1569 
1570 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1571 				 struct net_bridge_port *port,
1572 				 struct sk_buff *skb,
1573 				 u16 vid)
1574 {
1575 	struct sk_buff *skb_trimmed = NULL;
1576 	struct igmphdr *ih;
1577 	int err;
1578 
1579 	err = ip_mc_check_igmp(skb, &skb_trimmed);
1580 
1581 	if (err == -ENOMSG) {
1582 		if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr))
1583 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1584 		return 0;
1585 	} else if (err < 0) {
1586 		return err;
1587 	}
1588 
1589 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1590 	ih = igmp_hdr(skb);
1591 
1592 	switch (ih->type) {
1593 	case IGMP_HOST_MEMBERSHIP_REPORT:
1594 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1595 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1596 		err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1597 		break;
1598 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1599 		err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
1600 		break;
1601 	case IGMP_HOST_MEMBERSHIP_QUERY:
1602 		err = br_ip4_multicast_query(br, port, skb_trimmed, vid);
1603 		break;
1604 	case IGMP_HOST_LEAVE_MESSAGE:
1605 		br_ip4_multicast_leave_group(br, port, ih->group, vid);
1606 		break;
1607 	}
1608 
1609 	if (skb_trimmed && skb_trimmed != skb)
1610 		kfree_skb(skb_trimmed);
1611 
1612 	return err;
1613 }
1614 
1615 #if IS_ENABLED(CONFIG_IPV6)
1616 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1617 				 struct net_bridge_port *port,
1618 				 struct sk_buff *skb,
1619 				 u16 vid)
1620 {
1621 	struct sk_buff *skb_trimmed = NULL;
1622 	struct mld_msg *mld;
1623 	int err;
1624 
1625 	err = ipv6_mc_check_mld(skb, &skb_trimmed);
1626 
1627 	if (err == -ENOMSG) {
1628 		if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
1629 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1630 		return 0;
1631 	} else if (err < 0) {
1632 		return err;
1633 	}
1634 
1635 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1636 	mld = (struct mld_msg *)skb_transport_header(skb);
1637 
1638 	switch (mld->mld_type) {
1639 	case ICMPV6_MGM_REPORT:
1640 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1641 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1642 		break;
1643 	case ICMPV6_MLD2_REPORT:
1644 		err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
1645 		break;
1646 	case ICMPV6_MGM_QUERY:
1647 		err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
1648 		break;
1649 	case ICMPV6_MGM_REDUCTION:
1650 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1651 		break;
1652 	}
1653 
1654 	if (skb_trimmed && skb_trimmed != skb)
1655 		kfree_skb(skb_trimmed);
1656 
1657 	return err;
1658 }
1659 #endif
1660 
1661 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1662 		     struct sk_buff *skb, u16 vid)
1663 {
1664 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1665 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1666 
1667 	if (br->multicast_disabled)
1668 		return 0;
1669 
1670 	switch (skb->protocol) {
1671 	case htons(ETH_P_IP):
1672 		return br_multicast_ipv4_rcv(br, port, skb, vid);
1673 #if IS_ENABLED(CONFIG_IPV6)
1674 	case htons(ETH_P_IPV6):
1675 		return br_multicast_ipv6_rcv(br, port, skb, vid);
1676 #endif
1677 	}
1678 
1679 	return 0;
1680 }
1681 
1682 static void br_multicast_query_expired(struct net_bridge *br,
1683 				       struct bridge_mcast_own_query *query,
1684 				       struct bridge_mcast_querier *querier)
1685 {
1686 	spin_lock(&br->multicast_lock);
1687 	if (query->startup_sent < br->multicast_startup_query_count)
1688 		query->startup_sent++;
1689 
1690 	RCU_INIT_POINTER(querier->port, NULL);
1691 	br_multicast_send_query(br, NULL, query);
1692 	spin_unlock(&br->multicast_lock);
1693 }
1694 
1695 static void br_ip4_multicast_query_expired(unsigned long data)
1696 {
1697 	struct net_bridge *br = (void *)data;
1698 
1699 	br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1700 }
1701 
1702 #if IS_ENABLED(CONFIG_IPV6)
1703 static void br_ip6_multicast_query_expired(unsigned long data)
1704 {
1705 	struct net_bridge *br = (void *)data;
1706 
1707 	br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1708 }
1709 #endif
1710 
1711 void br_multicast_init(struct net_bridge *br)
1712 {
1713 	br->hash_elasticity = 4;
1714 	br->hash_max = 512;
1715 
1716 	br->multicast_router = 1;
1717 	br->multicast_querier = 0;
1718 	br->multicast_query_use_ifaddr = 0;
1719 	br->multicast_last_member_count = 2;
1720 	br->multicast_startup_query_count = 2;
1721 
1722 	br->multicast_last_member_interval = HZ;
1723 	br->multicast_query_response_interval = 10 * HZ;
1724 	br->multicast_startup_query_interval = 125 * HZ / 4;
1725 	br->multicast_query_interval = 125 * HZ;
1726 	br->multicast_querier_interval = 255 * HZ;
1727 	br->multicast_membership_interval = 260 * HZ;
1728 
1729 	br->ip4_other_query.delay_time = 0;
1730 	br->ip4_querier.port = NULL;
1731 #if IS_ENABLED(CONFIG_IPV6)
1732 	br->ip6_other_query.delay_time = 0;
1733 	br->ip6_querier.port = NULL;
1734 #endif
1735 
1736 	spin_lock_init(&br->multicast_lock);
1737 	setup_timer(&br->multicast_router_timer,
1738 		    br_multicast_local_router_expired, 0);
1739 	setup_timer(&br->ip4_other_query.timer,
1740 		    br_ip4_multicast_querier_expired, (unsigned long)br);
1741 	setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1742 		    (unsigned long)br);
1743 #if IS_ENABLED(CONFIG_IPV6)
1744 	setup_timer(&br->ip6_other_query.timer,
1745 		    br_ip6_multicast_querier_expired, (unsigned long)br);
1746 	setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1747 		    (unsigned long)br);
1748 #endif
1749 }
1750 
1751 static void __br_multicast_open(struct net_bridge *br,
1752 				struct bridge_mcast_own_query *query)
1753 {
1754 	query->startup_sent = 0;
1755 
1756 	if (br->multicast_disabled)
1757 		return;
1758 
1759 	mod_timer(&query->timer, jiffies);
1760 }
1761 
1762 void br_multicast_open(struct net_bridge *br)
1763 {
1764 	__br_multicast_open(br, &br->ip4_own_query);
1765 #if IS_ENABLED(CONFIG_IPV6)
1766 	__br_multicast_open(br, &br->ip6_own_query);
1767 #endif
1768 }
1769 
1770 void br_multicast_stop(struct net_bridge *br)
1771 {
1772 	del_timer_sync(&br->multicast_router_timer);
1773 	del_timer_sync(&br->ip4_other_query.timer);
1774 	del_timer_sync(&br->ip4_own_query.timer);
1775 #if IS_ENABLED(CONFIG_IPV6)
1776 	del_timer_sync(&br->ip6_other_query.timer);
1777 	del_timer_sync(&br->ip6_own_query.timer);
1778 #endif
1779 }
1780 
1781 void br_multicast_dev_del(struct net_bridge *br)
1782 {
1783 	struct net_bridge_mdb_htable *mdb;
1784 	struct net_bridge_mdb_entry *mp;
1785 	struct hlist_node *n;
1786 	u32 ver;
1787 	int i;
1788 
1789 	spin_lock_bh(&br->multicast_lock);
1790 	mdb = mlock_dereference(br->mdb, br);
1791 	if (!mdb)
1792 		goto out;
1793 
1794 	br->mdb = NULL;
1795 
1796 	ver = mdb->ver;
1797 	for (i = 0; i < mdb->max; i++) {
1798 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1799 					  hlist[ver]) {
1800 			del_timer(&mp->timer);
1801 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1802 		}
1803 	}
1804 
1805 	if (mdb->old) {
1806 		spin_unlock_bh(&br->multicast_lock);
1807 		rcu_barrier_bh();
1808 		spin_lock_bh(&br->multicast_lock);
1809 		WARN_ON(mdb->old);
1810 	}
1811 
1812 	mdb->old = mdb;
1813 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1814 
1815 out:
1816 	spin_unlock_bh(&br->multicast_lock);
1817 }
1818 
1819 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1820 {
1821 	int err = -EINVAL;
1822 
1823 	spin_lock_bh(&br->multicast_lock);
1824 
1825 	switch (val) {
1826 	case 0:
1827 	case 2:
1828 		del_timer(&br->multicast_router_timer);
1829 		/* fall through */
1830 	case 1:
1831 		br->multicast_router = val;
1832 		err = 0;
1833 		break;
1834 	}
1835 
1836 	spin_unlock_bh(&br->multicast_lock);
1837 
1838 	return err;
1839 }
1840 
1841 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1842 {
1843 	struct net_bridge *br = p->br;
1844 	int err = -EINVAL;
1845 
1846 	spin_lock(&br->multicast_lock);
1847 
1848 	switch (val) {
1849 	case 0:
1850 	case 1:
1851 	case 2:
1852 		p->multicast_router = val;
1853 		err = 0;
1854 
1855 		if (val < 2 && !hlist_unhashed(&p->rlist)) {
1856 			hlist_del_init_rcu(&p->rlist);
1857 			br_rtr_notify(br->dev, p, RTM_DELMDB);
1858 		}
1859 
1860 		if (val == 1)
1861 			break;
1862 
1863 		del_timer(&p->multicast_router_timer);
1864 
1865 		if (val == 0)
1866 			break;
1867 
1868 		br_multicast_add_router(br, p);
1869 		break;
1870 	}
1871 
1872 	spin_unlock(&br->multicast_lock);
1873 
1874 	return err;
1875 }
1876 
1877 static void br_multicast_start_querier(struct net_bridge *br,
1878 				       struct bridge_mcast_own_query *query)
1879 {
1880 	struct net_bridge_port *port;
1881 
1882 	__br_multicast_open(br, query);
1883 
1884 	list_for_each_entry(port, &br->port_list, list) {
1885 		if (port->state == BR_STATE_DISABLED ||
1886 		    port->state == BR_STATE_BLOCKING)
1887 			continue;
1888 
1889 		if (query == &br->ip4_own_query)
1890 			br_multicast_enable(&port->ip4_own_query);
1891 #if IS_ENABLED(CONFIG_IPV6)
1892 		else
1893 			br_multicast_enable(&port->ip6_own_query);
1894 #endif
1895 	}
1896 }
1897 
1898 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1899 {
1900 	int err = 0;
1901 	struct net_bridge_mdb_htable *mdb;
1902 
1903 	spin_lock_bh(&br->multicast_lock);
1904 	if (br->multicast_disabled == !val)
1905 		goto unlock;
1906 
1907 	br->multicast_disabled = !val;
1908 	if (br->multicast_disabled)
1909 		goto unlock;
1910 
1911 	if (!netif_running(br->dev))
1912 		goto unlock;
1913 
1914 	mdb = mlock_dereference(br->mdb, br);
1915 	if (mdb) {
1916 		if (mdb->old) {
1917 			err = -EEXIST;
1918 rollback:
1919 			br->multicast_disabled = !!val;
1920 			goto unlock;
1921 		}
1922 
1923 		err = br_mdb_rehash(&br->mdb, mdb->max,
1924 				    br->hash_elasticity);
1925 		if (err)
1926 			goto rollback;
1927 	}
1928 
1929 	br_multicast_start_querier(br, &br->ip4_own_query);
1930 #if IS_ENABLED(CONFIG_IPV6)
1931 	br_multicast_start_querier(br, &br->ip6_own_query);
1932 #endif
1933 
1934 unlock:
1935 	spin_unlock_bh(&br->multicast_lock);
1936 
1937 	return err;
1938 }
1939 
1940 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1941 {
1942 	unsigned long max_delay;
1943 
1944 	val = !!val;
1945 
1946 	spin_lock_bh(&br->multicast_lock);
1947 	if (br->multicast_querier == val)
1948 		goto unlock;
1949 
1950 	br->multicast_querier = val;
1951 	if (!val)
1952 		goto unlock;
1953 
1954 	max_delay = br->multicast_query_response_interval;
1955 
1956 	if (!timer_pending(&br->ip4_other_query.timer))
1957 		br->ip4_other_query.delay_time = jiffies + max_delay;
1958 
1959 	br_multicast_start_querier(br, &br->ip4_own_query);
1960 
1961 #if IS_ENABLED(CONFIG_IPV6)
1962 	if (!timer_pending(&br->ip6_other_query.timer))
1963 		br->ip6_other_query.delay_time = jiffies + max_delay;
1964 
1965 	br_multicast_start_querier(br, &br->ip6_own_query);
1966 #endif
1967 
1968 unlock:
1969 	spin_unlock_bh(&br->multicast_lock);
1970 
1971 	return 0;
1972 }
1973 
1974 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1975 {
1976 	int err = -EINVAL;
1977 	u32 old;
1978 	struct net_bridge_mdb_htable *mdb;
1979 
1980 	spin_lock_bh(&br->multicast_lock);
1981 	if (!is_power_of_2(val))
1982 		goto unlock;
1983 
1984 	mdb = mlock_dereference(br->mdb, br);
1985 	if (mdb && val < mdb->size)
1986 		goto unlock;
1987 
1988 	err = 0;
1989 
1990 	old = br->hash_max;
1991 	br->hash_max = val;
1992 
1993 	if (mdb) {
1994 		if (mdb->old) {
1995 			err = -EEXIST;
1996 rollback:
1997 			br->hash_max = old;
1998 			goto unlock;
1999 		}
2000 
2001 		err = br_mdb_rehash(&br->mdb, br->hash_max,
2002 				    br->hash_elasticity);
2003 		if (err)
2004 			goto rollback;
2005 	}
2006 
2007 unlock:
2008 	spin_unlock_bh(&br->multicast_lock);
2009 
2010 	return err;
2011 }
2012 
2013 /**
2014  * br_multicast_list_adjacent - Returns snooped multicast addresses
2015  * @dev:	The bridge port adjacent to which to retrieve addresses
2016  * @br_ip_list:	The list to store found, snooped multicast IP addresses in
2017  *
2018  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2019  * snooping feature on all bridge ports of dev's bridge device, excluding
2020  * the addresses from dev itself.
2021  *
2022  * Returns the number of items added to br_ip_list.
2023  *
2024  * Notes:
2025  * - br_ip_list needs to be initialized by caller
2026  * - br_ip_list might contain duplicates in the end
2027  *   (needs to be taken care of by caller)
2028  * - br_ip_list needs to be freed by caller
2029  */
2030 int br_multicast_list_adjacent(struct net_device *dev,
2031 			       struct list_head *br_ip_list)
2032 {
2033 	struct net_bridge *br;
2034 	struct net_bridge_port *port;
2035 	struct net_bridge_port_group *group;
2036 	struct br_ip_list *entry;
2037 	int count = 0;
2038 
2039 	rcu_read_lock();
2040 	if (!br_ip_list || !br_port_exists(dev))
2041 		goto unlock;
2042 
2043 	port = br_port_get_rcu(dev);
2044 	if (!port || !port->br)
2045 		goto unlock;
2046 
2047 	br = port->br;
2048 
2049 	list_for_each_entry_rcu(port, &br->port_list, list) {
2050 		if (!port->dev || port->dev == dev)
2051 			continue;
2052 
2053 		hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2054 			entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2055 			if (!entry)
2056 				goto unlock;
2057 
2058 			entry->addr = group->addr;
2059 			list_add(&entry->list, br_ip_list);
2060 			count++;
2061 		}
2062 	}
2063 
2064 unlock:
2065 	rcu_read_unlock();
2066 	return count;
2067 }
2068 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2069 
2070 /**
2071  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2072  * @dev: The bridge port providing the bridge on which to check for a querier
2073  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2074  *
2075  * Checks whether the given interface has a bridge on top and if so returns
2076  * true if a valid querier exists anywhere on the bridged link layer.
2077  * Otherwise returns false.
2078  */
2079 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2080 {
2081 	struct net_bridge *br;
2082 	struct net_bridge_port *port;
2083 	struct ethhdr eth;
2084 	bool ret = false;
2085 
2086 	rcu_read_lock();
2087 	if (!br_port_exists(dev))
2088 		goto unlock;
2089 
2090 	port = br_port_get_rcu(dev);
2091 	if (!port || !port->br)
2092 		goto unlock;
2093 
2094 	br = port->br;
2095 
2096 	memset(&eth, 0, sizeof(eth));
2097 	eth.h_proto = htons(proto);
2098 
2099 	ret = br_multicast_querier_exists(br, &eth);
2100 
2101 unlock:
2102 	rcu_read_unlock();
2103 	return ret;
2104 }
2105 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2106 
2107 /**
2108  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2109  * @dev: The bridge port adjacent to which to check for a querier
2110  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2111  *
2112  * Checks whether the given interface has a bridge on top and if so returns
2113  * true if a selected querier is behind one of the other ports of this
2114  * bridge. Otherwise returns false.
2115  */
2116 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2117 {
2118 	struct net_bridge *br;
2119 	struct net_bridge_port *port;
2120 	bool ret = false;
2121 
2122 	rcu_read_lock();
2123 	if (!br_port_exists(dev))
2124 		goto unlock;
2125 
2126 	port = br_port_get_rcu(dev);
2127 	if (!port || !port->br)
2128 		goto unlock;
2129 
2130 	br = port->br;
2131 
2132 	switch (proto) {
2133 	case ETH_P_IP:
2134 		if (!timer_pending(&br->ip4_other_query.timer) ||
2135 		    rcu_dereference(br->ip4_querier.port) == port)
2136 			goto unlock;
2137 		break;
2138 #if IS_ENABLED(CONFIG_IPV6)
2139 	case ETH_P_IPV6:
2140 		if (!timer_pending(&br->ip6_other_query.timer) ||
2141 		    rcu_dereference(br->ip6_querier.port) == port)
2142 			goto unlock;
2143 		break;
2144 #endif
2145 	default:
2146 		goto unlock;
2147 	}
2148 
2149 	ret = true;
2150 unlock:
2151 	rcu_read_unlock();
2152 	return ret;
2153 }
2154 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);
2155