xref: /openbmc/linux/net/bridge/br_multicast.c (revision 827634ad)
1 /*
2  * Bridge multicast support.
3  *
4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/if_ether.h>
16 #include <linux/igmp.h>
17 #include <linux/jhash.h>
18 #include <linux/kernel.h>
19 #include <linux/log2.h>
20 #include <linux/netdevice.h>
21 #include <linux/netfilter_bridge.h>
22 #include <linux/random.h>
23 #include <linux/rculist.h>
24 #include <linux/skbuff.h>
25 #include <linux/slab.h>
26 #include <linux/timer.h>
27 #include <linux/inetdevice.h>
28 #include <net/ip.h>
29 #if IS_ENABLED(CONFIG_IPV6)
30 #include <net/ipv6.h>
31 #include <net/mld.h>
32 #include <net/ip6_checksum.h>
33 #include <net/addrconf.h>
34 #endif
35 
36 #include "br_private.h"
37 
38 static void br_multicast_start_querier(struct net_bridge *br,
39 				       struct bridge_mcast_own_query *query);
40 unsigned int br_mdb_rehash_seq;
41 
42 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
43 {
44 	if (a->proto != b->proto)
45 		return 0;
46 	if (a->vid != b->vid)
47 		return 0;
48 	switch (a->proto) {
49 	case htons(ETH_P_IP):
50 		return a->u.ip4 == b->u.ip4;
51 #if IS_ENABLED(CONFIG_IPV6)
52 	case htons(ETH_P_IPV6):
53 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
54 #endif
55 	}
56 	return 0;
57 }
58 
59 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
60 				__u16 vid)
61 {
62 	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
63 }
64 
65 #if IS_ENABLED(CONFIG_IPV6)
66 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
67 				const struct in6_addr *ip,
68 				__u16 vid)
69 {
70 	return jhash_2words(ipv6_addr_hash(ip), vid,
71 			    mdb->secret) & (mdb->max - 1);
72 }
73 #endif
74 
75 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
76 			     struct br_ip *ip)
77 {
78 	switch (ip->proto) {
79 	case htons(ETH_P_IP):
80 		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
81 #if IS_ENABLED(CONFIG_IPV6)
82 	case htons(ETH_P_IPV6):
83 		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
84 #endif
85 	}
86 	return 0;
87 }
88 
89 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
90 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
91 {
92 	struct net_bridge_mdb_entry *mp;
93 
94 	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
95 		if (br_ip_equal(&mp->addr, dst))
96 			return mp;
97 	}
98 
99 	return NULL;
100 }
101 
102 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
103 					   struct br_ip *dst)
104 {
105 	if (!mdb)
106 		return NULL;
107 
108 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
109 }
110 
111 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
112 	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
113 {
114 	struct br_ip br_dst;
115 
116 	br_dst.u.ip4 = dst;
117 	br_dst.proto = htons(ETH_P_IP);
118 	br_dst.vid = vid;
119 
120 	return br_mdb_ip_get(mdb, &br_dst);
121 }
122 
123 #if IS_ENABLED(CONFIG_IPV6)
124 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
125 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
126 	__u16 vid)
127 {
128 	struct br_ip br_dst;
129 
130 	br_dst.u.ip6 = *dst;
131 	br_dst.proto = htons(ETH_P_IPV6);
132 	br_dst.vid = vid;
133 
134 	return br_mdb_ip_get(mdb, &br_dst);
135 }
136 #endif
137 
138 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
139 					struct sk_buff *skb, u16 vid)
140 {
141 	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
142 	struct br_ip ip;
143 
144 	if (br->multicast_disabled)
145 		return NULL;
146 
147 	if (BR_INPUT_SKB_CB(skb)->igmp)
148 		return NULL;
149 
150 	ip.proto = skb->protocol;
151 	ip.vid = vid;
152 
153 	switch (skb->protocol) {
154 	case htons(ETH_P_IP):
155 		ip.u.ip4 = ip_hdr(skb)->daddr;
156 		break;
157 #if IS_ENABLED(CONFIG_IPV6)
158 	case htons(ETH_P_IPV6):
159 		ip.u.ip6 = ipv6_hdr(skb)->daddr;
160 		break;
161 #endif
162 	default:
163 		return NULL;
164 	}
165 
166 	return br_mdb_ip_get(mdb, &ip);
167 }
168 
169 static void br_mdb_free(struct rcu_head *head)
170 {
171 	struct net_bridge_mdb_htable *mdb =
172 		container_of(head, struct net_bridge_mdb_htable, rcu);
173 	struct net_bridge_mdb_htable *old = mdb->old;
174 
175 	mdb->old = NULL;
176 	kfree(old->mhash);
177 	kfree(old);
178 }
179 
180 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
181 		       struct net_bridge_mdb_htable *old,
182 		       int elasticity)
183 {
184 	struct net_bridge_mdb_entry *mp;
185 	int maxlen;
186 	int len;
187 	int i;
188 
189 	for (i = 0; i < old->max; i++)
190 		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
191 			hlist_add_head(&mp->hlist[new->ver],
192 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
193 
194 	if (!elasticity)
195 		return 0;
196 
197 	maxlen = 0;
198 	for (i = 0; i < new->max; i++) {
199 		len = 0;
200 		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
201 			len++;
202 		if (len > maxlen)
203 			maxlen = len;
204 	}
205 
206 	return maxlen > elasticity ? -EINVAL : 0;
207 }
208 
209 void br_multicast_free_pg(struct rcu_head *head)
210 {
211 	struct net_bridge_port_group *p =
212 		container_of(head, struct net_bridge_port_group, rcu);
213 
214 	kfree(p);
215 }
216 
217 static void br_multicast_free_group(struct rcu_head *head)
218 {
219 	struct net_bridge_mdb_entry *mp =
220 		container_of(head, struct net_bridge_mdb_entry, rcu);
221 
222 	kfree(mp);
223 }
224 
225 static void br_multicast_group_expired(unsigned long data)
226 {
227 	struct net_bridge_mdb_entry *mp = (void *)data;
228 	struct net_bridge *br = mp->br;
229 	struct net_bridge_mdb_htable *mdb;
230 
231 	spin_lock(&br->multicast_lock);
232 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
233 		goto out;
234 
235 	mp->mglist = false;
236 
237 	if (mp->ports)
238 		goto out;
239 
240 	mdb = mlock_dereference(br->mdb, br);
241 
242 	hlist_del_rcu(&mp->hlist[mdb->ver]);
243 	mdb->size--;
244 
245 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
246 
247 out:
248 	spin_unlock(&br->multicast_lock);
249 }
250 
251 static void br_multicast_del_pg(struct net_bridge *br,
252 				struct net_bridge_port_group *pg)
253 {
254 	struct net_bridge_mdb_htable *mdb;
255 	struct net_bridge_mdb_entry *mp;
256 	struct net_bridge_port_group *p;
257 	struct net_bridge_port_group __rcu **pp;
258 
259 	mdb = mlock_dereference(br->mdb, br);
260 
261 	mp = br_mdb_ip_get(mdb, &pg->addr);
262 	if (WARN_ON(!mp))
263 		return;
264 
265 	for (pp = &mp->ports;
266 	     (p = mlock_dereference(*pp, br)) != NULL;
267 	     pp = &p->next) {
268 		if (p != pg)
269 			continue;
270 
271 		rcu_assign_pointer(*pp, p->next);
272 		hlist_del_init(&p->mglist);
273 		del_timer(&p->timer);
274 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
275 
276 		if (!mp->ports && !mp->mglist &&
277 		    netif_running(br->dev))
278 			mod_timer(&mp->timer, jiffies);
279 
280 		return;
281 	}
282 
283 	WARN_ON(1);
284 }
285 
286 static void br_multicast_port_group_expired(unsigned long data)
287 {
288 	struct net_bridge_port_group *pg = (void *)data;
289 	struct net_bridge *br = pg->port->br;
290 
291 	spin_lock(&br->multicast_lock);
292 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
293 	    hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
294 		goto out;
295 
296 	br_multicast_del_pg(br, pg);
297 
298 out:
299 	spin_unlock(&br->multicast_lock);
300 }
301 
302 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
303 			 int elasticity)
304 {
305 	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
306 	struct net_bridge_mdb_htable *mdb;
307 	int err;
308 
309 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
310 	if (!mdb)
311 		return -ENOMEM;
312 
313 	mdb->max = max;
314 	mdb->old = old;
315 
316 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
317 	if (!mdb->mhash) {
318 		kfree(mdb);
319 		return -ENOMEM;
320 	}
321 
322 	mdb->size = old ? old->size : 0;
323 	mdb->ver = old ? old->ver ^ 1 : 0;
324 
325 	if (!old || elasticity)
326 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
327 	else
328 		mdb->secret = old->secret;
329 
330 	if (!old)
331 		goto out;
332 
333 	err = br_mdb_copy(mdb, old, elasticity);
334 	if (err) {
335 		kfree(mdb->mhash);
336 		kfree(mdb);
337 		return err;
338 	}
339 
340 	br_mdb_rehash_seq++;
341 	call_rcu_bh(&mdb->rcu, br_mdb_free);
342 
343 out:
344 	rcu_assign_pointer(*mdbp, mdb);
345 
346 	return 0;
347 }
348 
349 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
350 						    __be32 group)
351 {
352 	struct sk_buff *skb;
353 	struct igmphdr *ih;
354 	struct ethhdr *eth;
355 	struct iphdr *iph;
356 
357 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
358 						 sizeof(*ih) + 4);
359 	if (!skb)
360 		goto out;
361 
362 	skb->protocol = htons(ETH_P_IP);
363 
364 	skb_reset_mac_header(skb);
365 	eth = eth_hdr(skb);
366 
367 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
368 	eth->h_dest[0] = 1;
369 	eth->h_dest[1] = 0;
370 	eth->h_dest[2] = 0x5e;
371 	eth->h_dest[3] = 0;
372 	eth->h_dest[4] = 0;
373 	eth->h_dest[5] = 1;
374 	eth->h_proto = htons(ETH_P_IP);
375 	skb_put(skb, sizeof(*eth));
376 
377 	skb_set_network_header(skb, skb->len);
378 	iph = ip_hdr(skb);
379 
380 	iph->version = 4;
381 	iph->ihl = 6;
382 	iph->tos = 0xc0;
383 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
384 	iph->id = 0;
385 	iph->frag_off = htons(IP_DF);
386 	iph->ttl = 1;
387 	iph->protocol = IPPROTO_IGMP;
388 	iph->saddr = br->multicast_query_use_ifaddr ?
389 		     inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
390 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
391 	((u8 *)&iph[1])[0] = IPOPT_RA;
392 	((u8 *)&iph[1])[1] = 4;
393 	((u8 *)&iph[1])[2] = 0;
394 	((u8 *)&iph[1])[3] = 0;
395 	ip_send_check(iph);
396 	skb_put(skb, 24);
397 
398 	skb_set_transport_header(skb, skb->len);
399 	ih = igmp_hdr(skb);
400 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
401 	ih->code = (group ? br->multicast_last_member_interval :
402 			    br->multicast_query_response_interval) /
403 		   (HZ / IGMP_TIMER_SCALE);
404 	ih->group = group;
405 	ih->csum = 0;
406 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
407 	skb_put(skb, sizeof(*ih));
408 
409 	__skb_pull(skb, sizeof(*eth));
410 
411 out:
412 	return skb;
413 }
414 
415 #if IS_ENABLED(CONFIG_IPV6)
416 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
417 						    const struct in6_addr *group)
418 {
419 	struct sk_buff *skb;
420 	struct ipv6hdr *ip6h;
421 	struct mld_msg *mldq;
422 	struct ethhdr *eth;
423 	u8 *hopopt;
424 	unsigned long interval;
425 
426 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
427 						 8 + sizeof(*mldq));
428 	if (!skb)
429 		goto out;
430 
431 	skb->protocol = htons(ETH_P_IPV6);
432 
433 	/* Ethernet header */
434 	skb_reset_mac_header(skb);
435 	eth = eth_hdr(skb);
436 
437 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
438 	eth->h_proto = htons(ETH_P_IPV6);
439 	skb_put(skb, sizeof(*eth));
440 
441 	/* IPv6 header + HbH option */
442 	skb_set_network_header(skb, skb->len);
443 	ip6h = ipv6_hdr(skb);
444 
445 	*(__force __be32 *)ip6h = htonl(0x60000000);
446 	ip6h->payload_len = htons(8 + sizeof(*mldq));
447 	ip6h->nexthdr = IPPROTO_HOPOPTS;
448 	ip6h->hop_limit = 1;
449 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
450 	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
451 			       &ip6h->saddr)) {
452 		kfree_skb(skb);
453 		return NULL;
454 	}
455 	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
456 
457 	hopopt = (u8 *)(ip6h + 1);
458 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
459 	hopopt[1] = 0;				/* length of HbH */
460 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
461 	hopopt[3] = 2;				/* Length of RA Option */
462 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
463 	hopopt[5] = 0;
464 	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
465 	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
466 
467 	skb_put(skb, sizeof(*ip6h) + 8);
468 
469 	/* ICMPv6 */
470 	skb_set_transport_header(skb, skb->len);
471 	mldq = (struct mld_msg *) icmp6_hdr(skb);
472 
473 	interval = ipv6_addr_any(group) ?
474 			br->multicast_query_response_interval :
475 			br->multicast_last_member_interval;
476 
477 	mldq->mld_type = ICMPV6_MGM_QUERY;
478 	mldq->mld_code = 0;
479 	mldq->mld_cksum = 0;
480 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
481 	mldq->mld_reserved = 0;
482 	mldq->mld_mca = *group;
483 
484 	/* checksum */
485 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
486 					  sizeof(*mldq), IPPROTO_ICMPV6,
487 					  csum_partial(mldq,
488 						       sizeof(*mldq), 0));
489 	skb_put(skb, sizeof(*mldq));
490 
491 	__skb_pull(skb, sizeof(*eth));
492 
493 out:
494 	return skb;
495 }
496 #endif
497 
498 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
499 						struct br_ip *addr)
500 {
501 	switch (addr->proto) {
502 	case htons(ETH_P_IP):
503 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
504 #if IS_ENABLED(CONFIG_IPV6)
505 	case htons(ETH_P_IPV6):
506 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
507 #endif
508 	}
509 	return NULL;
510 }
511 
512 static struct net_bridge_mdb_entry *br_multicast_get_group(
513 	struct net_bridge *br, struct net_bridge_port *port,
514 	struct br_ip *group, int hash)
515 {
516 	struct net_bridge_mdb_htable *mdb;
517 	struct net_bridge_mdb_entry *mp;
518 	unsigned int count = 0;
519 	unsigned int max;
520 	int elasticity;
521 	int err;
522 
523 	mdb = rcu_dereference_protected(br->mdb, 1);
524 	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
525 		count++;
526 		if (unlikely(br_ip_equal(group, &mp->addr)))
527 			return mp;
528 	}
529 
530 	elasticity = 0;
531 	max = mdb->max;
532 
533 	if (unlikely(count > br->hash_elasticity && count)) {
534 		if (net_ratelimit())
535 			br_info(br, "Multicast hash table "
536 				"chain limit reached: %s\n",
537 				port ? port->dev->name : br->dev->name);
538 
539 		elasticity = br->hash_elasticity;
540 	}
541 
542 	if (mdb->size >= max) {
543 		max *= 2;
544 		if (unlikely(max > br->hash_max)) {
545 			br_warn(br, "Multicast hash table maximum of %d "
546 				"reached, disabling snooping: %s\n",
547 				br->hash_max,
548 				port ? port->dev->name : br->dev->name);
549 			err = -E2BIG;
550 disable:
551 			br->multicast_disabled = 1;
552 			goto err;
553 		}
554 	}
555 
556 	if (max > mdb->max || elasticity) {
557 		if (mdb->old) {
558 			if (net_ratelimit())
559 				br_info(br, "Multicast hash table "
560 					"on fire: %s\n",
561 					port ? port->dev->name : br->dev->name);
562 			err = -EEXIST;
563 			goto err;
564 		}
565 
566 		err = br_mdb_rehash(&br->mdb, max, elasticity);
567 		if (err) {
568 			br_warn(br, "Cannot rehash multicast "
569 				"hash table, disabling snooping: %s, %d, %d\n",
570 				port ? port->dev->name : br->dev->name,
571 				mdb->size, err);
572 			goto disable;
573 		}
574 
575 		err = -EAGAIN;
576 		goto err;
577 	}
578 
579 	return NULL;
580 
581 err:
582 	mp = ERR_PTR(err);
583 	return mp;
584 }
585 
586 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
587 	struct net_bridge_port *port, struct br_ip *group)
588 {
589 	struct net_bridge_mdb_htable *mdb;
590 	struct net_bridge_mdb_entry *mp;
591 	int hash;
592 	int err;
593 
594 	mdb = rcu_dereference_protected(br->mdb, 1);
595 	if (!mdb) {
596 		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
597 		if (err)
598 			return ERR_PTR(err);
599 		goto rehash;
600 	}
601 
602 	hash = br_ip_hash(mdb, group);
603 	mp = br_multicast_get_group(br, port, group, hash);
604 	switch (PTR_ERR(mp)) {
605 	case 0:
606 		break;
607 
608 	case -EAGAIN:
609 rehash:
610 		mdb = rcu_dereference_protected(br->mdb, 1);
611 		hash = br_ip_hash(mdb, group);
612 		break;
613 
614 	default:
615 		goto out;
616 	}
617 
618 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
619 	if (unlikely(!mp))
620 		return ERR_PTR(-ENOMEM);
621 
622 	mp->br = br;
623 	mp->addr = *group;
624 	setup_timer(&mp->timer, br_multicast_group_expired,
625 		    (unsigned long)mp);
626 
627 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
628 	mdb->size++;
629 
630 out:
631 	return mp;
632 }
633 
634 struct net_bridge_port_group *br_multicast_new_port_group(
635 			struct net_bridge_port *port,
636 			struct br_ip *group,
637 			struct net_bridge_port_group __rcu *next,
638 			unsigned char state)
639 {
640 	struct net_bridge_port_group *p;
641 
642 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
643 	if (unlikely(!p))
644 		return NULL;
645 
646 	p->addr = *group;
647 	p->port = port;
648 	p->state = state;
649 	rcu_assign_pointer(p->next, next);
650 	hlist_add_head(&p->mglist, &port->mglist);
651 	setup_timer(&p->timer, br_multicast_port_group_expired,
652 		    (unsigned long)p);
653 	return p;
654 }
655 
656 static int br_multicast_add_group(struct net_bridge *br,
657 				  struct net_bridge_port *port,
658 				  struct br_ip *group)
659 {
660 	struct net_bridge_mdb_entry *mp;
661 	struct net_bridge_port_group *p;
662 	struct net_bridge_port_group __rcu **pp;
663 	unsigned long now = jiffies;
664 	int err;
665 
666 	spin_lock(&br->multicast_lock);
667 	if (!netif_running(br->dev) ||
668 	    (port && port->state == BR_STATE_DISABLED))
669 		goto out;
670 
671 	mp = br_multicast_new_group(br, port, group);
672 	err = PTR_ERR(mp);
673 	if (IS_ERR(mp))
674 		goto err;
675 
676 	if (!port) {
677 		mp->mglist = true;
678 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
679 		goto out;
680 	}
681 
682 	for (pp = &mp->ports;
683 	     (p = mlock_dereference(*pp, br)) != NULL;
684 	     pp = &p->next) {
685 		if (p->port == port)
686 			goto found;
687 		if ((unsigned long)p->port < (unsigned long)port)
688 			break;
689 	}
690 
691 	p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
692 	if (unlikely(!p))
693 		goto err;
694 	rcu_assign_pointer(*pp, p);
695 	br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
696 
697 found:
698 	mod_timer(&p->timer, now + br->multicast_membership_interval);
699 out:
700 	err = 0;
701 
702 err:
703 	spin_unlock(&br->multicast_lock);
704 	return err;
705 }
706 
707 static int br_ip4_multicast_add_group(struct net_bridge *br,
708 				      struct net_bridge_port *port,
709 				      __be32 group,
710 				      __u16 vid)
711 {
712 	struct br_ip br_group;
713 
714 	if (ipv4_is_local_multicast(group))
715 		return 0;
716 
717 	br_group.u.ip4 = group;
718 	br_group.proto = htons(ETH_P_IP);
719 	br_group.vid = vid;
720 
721 	return br_multicast_add_group(br, port, &br_group);
722 }
723 
724 #if IS_ENABLED(CONFIG_IPV6)
725 static int br_ip6_multicast_add_group(struct net_bridge *br,
726 				      struct net_bridge_port *port,
727 				      const struct in6_addr *group,
728 				      __u16 vid)
729 {
730 	struct br_ip br_group;
731 
732 	if (ipv6_addr_is_ll_all_nodes(group))
733 		return 0;
734 
735 	br_group.u.ip6 = *group;
736 	br_group.proto = htons(ETH_P_IPV6);
737 	br_group.vid = vid;
738 
739 	return br_multicast_add_group(br, port, &br_group);
740 }
741 #endif
742 
743 static void br_multicast_router_expired(unsigned long data)
744 {
745 	struct net_bridge_port *port = (void *)data;
746 	struct net_bridge *br = port->br;
747 
748 	spin_lock(&br->multicast_lock);
749 	if (port->multicast_router != 1 ||
750 	    timer_pending(&port->multicast_router_timer) ||
751 	    hlist_unhashed(&port->rlist))
752 		goto out;
753 
754 	hlist_del_init_rcu(&port->rlist);
755 
756 out:
757 	spin_unlock(&br->multicast_lock);
758 }
759 
760 static void br_multicast_local_router_expired(unsigned long data)
761 {
762 }
763 
764 static void br_multicast_querier_expired(struct net_bridge *br,
765 					 struct bridge_mcast_own_query *query)
766 {
767 	spin_lock(&br->multicast_lock);
768 	if (!netif_running(br->dev) || br->multicast_disabled)
769 		goto out;
770 
771 	br_multicast_start_querier(br, query);
772 
773 out:
774 	spin_unlock(&br->multicast_lock);
775 }
776 
777 static void br_ip4_multicast_querier_expired(unsigned long data)
778 {
779 	struct net_bridge *br = (void *)data;
780 
781 	br_multicast_querier_expired(br, &br->ip4_own_query);
782 }
783 
784 #if IS_ENABLED(CONFIG_IPV6)
785 static void br_ip6_multicast_querier_expired(unsigned long data)
786 {
787 	struct net_bridge *br = (void *)data;
788 
789 	br_multicast_querier_expired(br, &br->ip6_own_query);
790 }
791 #endif
792 
793 static void br_multicast_select_own_querier(struct net_bridge *br,
794 					    struct br_ip *ip,
795 					    struct sk_buff *skb)
796 {
797 	if (ip->proto == htons(ETH_P_IP))
798 		br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
799 #if IS_ENABLED(CONFIG_IPV6)
800 	else
801 		br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
802 #endif
803 }
804 
805 static void __br_multicast_send_query(struct net_bridge *br,
806 				      struct net_bridge_port *port,
807 				      struct br_ip *ip)
808 {
809 	struct sk_buff *skb;
810 
811 	skb = br_multicast_alloc_query(br, ip);
812 	if (!skb)
813 		return;
814 
815 	if (port) {
816 		skb->dev = port->dev;
817 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, NULL, skb,
818 			NULL, skb->dev,
819 			br_dev_queue_push_xmit);
820 	} else {
821 		br_multicast_select_own_querier(br, ip, skb);
822 		netif_rx(skb);
823 	}
824 }
825 
826 static void br_multicast_send_query(struct net_bridge *br,
827 				    struct net_bridge_port *port,
828 				    struct bridge_mcast_own_query *own_query)
829 {
830 	unsigned long time;
831 	struct br_ip br_group;
832 	struct bridge_mcast_other_query *other_query = NULL;
833 
834 	if (!netif_running(br->dev) || br->multicast_disabled ||
835 	    !br->multicast_querier)
836 		return;
837 
838 	memset(&br_group.u, 0, sizeof(br_group.u));
839 
840 	if (port ? (own_query == &port->ip4_own_query) :
841 		   (own_query == &br->ip4_own_query)) {
842 		other_query = &br->ip4_other_query;
843 		br_group.proto = htons(ETH_P_IP);
844 #if IS_ENABLED(CONFIG_IPV6)
845 	} else {
846 		other_query = &br->ip6_other_query;
847 		br_group.proto = htons(ETH_P_IPV6);
848 #endif
849 	}
850 
851 	if (!other_query || timer_pending(&other_query->timer))
852 		return;
853 
854 	__br_multicast_send_query(br, port, &br_group);
855 
856 	time = jiffies;
857 	time += own_query->startup_sent < br->multicast_startup_query_count ?
858 		br->multicast_startup_query_interval :
859 		br->multicast_query_interval;
860 	mod_timer(&own_query->timer, time);
861 }
862 
863 static void
864 br_multicast_port_query_expired(struct net_bridge_port *port,
865 				struct bridge_mcast_own_query *query)
866 {
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 (query->startup_sent < br->multicast_startup_query_count)
875 		query->startup_sent++;
876 
877 	br_multicast_send_query(port->br, port, query);
878 
879 out:
880 	spin_unlock(&br->multicast_lock);
881 }
882 
883 static void br_ip4_multicast_port_query_expired(unsigned long data)
884 {
885 	struct net_bridge_port *port = (void *)data;
886 
887 	br_multicast_port_query_expired(port, &port->ip4_own_query);
888 }
889 
890 #if IS_ENABLED(CONFIG_IPV6)
891 static void br_ip6_multicast_port_query_expired(unsigned long data)
892 {
893 	struct net_bridge_port *port = (void *)data;
894 
895 	br_multicast_port_query_expired(port, &port->ip6_own_query);
896 }
897 #endif
898 
899 void br_multicast_add_port(struct net_bridge_port *port)
900 {
901 	port->multicast_router = 1;
902 
903 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
904 		    (unsigned long)port);
905 	setup_timer(&port->ip4_own_query.timer,
906 		    br_ip4_multicast_port_query_expired, (unsigned long)port);
907 #if IS_ENABLED(CONFIG_IPV6)
908 	setup_timer(&port->ip6_own_query.timer,
909 		    br_ip6_multicast_port_query_expired, (unsigned long)port);
910 #endif
911 }
912 
913 void br_multicast_del_port(struct net_bridge_port *port)
914 {
915 	del_timer_sync(&port->multicast_router_timer);
916 }
917 
918 static void br_multicast_enable(struct bridge_mcast_own_query *query)
919 {
920 	query->startup_sent = 0;
921 
922 	if (try_to_del_timer_sync(&query->timer) >= 0 ||
923 	    del_timer(&query->timer))
924 		mod_timer(&query->timer, jiffies);
925 }
926 
927 void br_multicast_enable_port(struct net_bridge_port *port)
928 {
929 	struct net_bridge *br = port->br;
930 
931 	spin_lock(&br->multicast_lock);
932 	if (br->multicast_disabled || !netif_running(br->dev))
933 		goto out;
934 
935 	br_multicast_enable(&port->ip4_own_query);
936 #if IS_ENABLED(CONFIG_IPV6)
937 	br_multicast_enable(&port->ip6_own_query);
938 #endif
939 
940 out:
941 	spin_unlock(&br->multicast_lock);
942 }
943 
944 void br_multicast_disable_port(struct net_bridge_port *port)
945 {
946 	struct net_bridge *br = port->br;
947 	struct net_bridge_port_group *pg;
948 	struct hlist_node *n;
949 
950 	spin_lock(&br->multicast_lock);
951 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
952 		br_multicast_del_pg(br, pg);
953 
954 	if (!hlist_unhashed(&port->rlist))
955 		hlist_del_init_rcu(&port->rlist);
956 	del_timer(&port->multicast_router_timer);
957 	del_timer(&port->ip4_own_query.timer);
958 #if IS_ENABLED(CONFIG_IPV6)
959 	del_timer(&port->ip6_own_query.timer);
960 #endif
961 	spin_unlock(&br->multicast_lock);
962 }
963 
964 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
965 					 struct net_bridge_port *port,
966 					 struct sk_buff *skb,
967 					 u16 vid)
968 {
969 	struct igmpv3_report *ih;
970 	struct igmpv3_grec *grec;
971 	int i;
972 	int len;
973 	int num;
974 	int type;
975 	int err = 0;
976 	__be32 group;
977 
978 	if (!pskb_may_pull(skb, sizeof(*ih)))
979 		return -EINVAL;
980 
981 	ih = igmpv3_report_hdr(skb);
982 	num = ntohs(ih->ngrec);
983 	len = sizeof(*ih);
984 
985 	for (i = 0; i < num; i++) {
986 		len += sizeof(*grec);
987 		if (!pskb_may_pull(skb, len))
988 			return -EINVAL;
989 
990 		grec = (void *)(skb->data + len - sizeof(*grec));
991 		group = grec->grec_mca;
992 		type = grec->grec_type;
993 
994 		len += ntohs(grec->grec_nsrcs) * 4;
995 		if (!pskb_may_pull(skb, len))
996 			return -EINVAL;
997 
998 		/* We treat this as an IGMPv2 report for now. */
999 		switch (type) {
1000 		case IGMPV3_MODE_IS_INCLUDE:
1001 		case IGMPV3_MODE_IS_EXCLUDE:
1002 		case IGMPV3_CHANGE_TO_INCLUDE:
1003 		case IGMPV3_CHANGE_TO_EXCLUDE:
1004 		case IGMPV3_ALLOW_NEW_SOURCES:
1005 		case IGMPV3_BLOCK_OLD_SOURCES:
1006 			break;
1007 
1008 		default:
1009 			continue;
1010 		}
1011 
1012 		err = br_ip4_multicast_add_group(br, port, group, vid);
1013 		if (err)
1014 			break;
1015 	}
1016 
1017 	return err;
1018 }
1019 
1020 #if IS_ENABLED(CONFIG_IPV6)
1021 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1022 					struct net_bridge_port *port,
1023 					struct sk_buff *skb,
1024 					u16 vid)
1025 {
1026 	struct icmp6hdr *icmp6h;
1027 	struct mld2_grec *grec;
1028 	int i;
1029 	int len;
1030 	int num;
1031 	int err = 0;
1032 
1033 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1034 		return -EINVAL;
1035 
1036 	icmp6h = icmp6_hdr(skb);
1037 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1038 	len = sizeof(*icmp6h);
1039 
1040 	for (i = 0; i < num; i++) {
1041 		__be16 *nsrcs, _nsrcs;
1042 
1043 		nsrcs = skb_header_pointer(skb,
1044 					   len + offsetof(struct mld2_grec,
1045 							  grec_nsrcs),
1046 					   sizeof(_nsrcs), &_nsrcs);
1047 		if (!nsrcs)
1048 			return -EINVAL;
1049 
1050 		if (!pskb_may_pull(skb,
1051 				   len + sizeof(*grec) +
1052 				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
1053 			return -EINVAL;
1054 
1055 		grec = (struct mld2_grec *)(skb->data + len);
1056 		len += sizeof(*grec) +
1057 		       sizeof(struct in6_addr) * ntohs(*nsrcs);
1058 
1059 		/* We treat these as MLDv1 reports for now. */
1060 		switch (grec->grec_type) {
1061 		case MLD2_MODE_IS_INCLUDE:
1062 		case MLD2_MODE_IS_EXCLUDE:
1063 		case MLD2_CHANGE_TO_INCLUDE:
1064 		case MLD2_CHANGE_TO_EXCLUDE:
1065 		case MLD2_ALLOW_NEW_SOURCES:
1066 		case MLD2_BLOCK_OLD_SOURCES:
1067 			break;
1068 
1069 		default:
1070 			continue;
1071 		}
1072 
1073 		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1074 						 vid);
1075 		if (!err)
1076 			break;
1077 	}
1078 
1079 	return err;
1080 }
1081 #endif
1082 
1083 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1084 					    struct net_bridge_port *port,
1085 					    __be32 saddr)
1086 {
1087 	if (!timer_pending(&br->ip4_own_query.timer) &&
1088 	    !timer_pending(&br->ip4_other_query.timer))
1089 		goto update;
1090 
1091 	if (!br->ip4_querier.addr.u.ip4)
1092 		goto update;
1093 
1094 	if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1095 		goto update;
1096 
1097 	return false;
1098 
1099 update:
1100 	br->ip4_querier.addr.u.ip4 = saddr;
1101 
1102 	/* update protected by general multicast_lock by caller */
1103 	rcu_assign_pointer(br->ip4_querier.port, port);
1104 
1105 	return true;
1106 }
1107 
1108 #if IS_ENABLED(CONFIG_IPV6)
1109 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1110 					    struct net_bridge_port *port,
1111 					    struct in6_addr *saddr)
1112 {
1113 	if (!timer_pending(&br->ip6_own_query.timer) &&
1114 	    !timer_pending(&br->ip6_other_query.timer))
1115 		goto update;
1116 
1117 	if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1118 		goto update;
1119 
1120 	return false;
1121 
1122 update:
1123 	br->ip6_querier.addr.u.ip6 = *saddr;
1124 
1125 	/* update protected by general multicast_lock by caller */
1126 	rcu_assign_pointer(br->ip6_querier.port, port);
1127 
1128 	return true;
1129 }
1130 #endif
1131 
1132 static bool br_multicast_select_querier(struct net_bridge *br,
1133 					struct net_bridge_port *port,
1134 					struct br_ip *saddr)
1135 {
1136 	switch (saddr->proto) {
1137 	case htons(ETH_P_IP):
1138 		return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1139 #if IS_ENABLED(CONFIG_IPV6)
1140 	case htons(ETH_P_IPV6):
1141 		return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1142 #endif
1143 	}
1144 
1145 	return false;
1146 }
1147 
1148 static void
1149 br_multicast_update_query_timer(struct net_bridge *br,
1150 				struct bridge_mcast_other_query *query,
1151 				unsigned long max_delay)
1152 {
1153 	if (!timer_pending(&query->timer))
1154 		query->delay_time = jiffies + max_delay;
1155 
1156 	mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1157 }
1158 
1159 /*
1160  * Add port to router_list
1161  *  list is maintained ordered by pointer value
1162  *  and locked by br->multicast_lock and RCU
1163  */
1164 static void br_multicast_add_router(struct net_bridge *br,
1165 				    struct net_bridge_port *port)
1166 {
1167 	struct net_bridge_port *p;
1168 	struct hlist_node *slot = NULL;
1169 
1170 	hlist_for_each_entry(p, &br->router_list, rlist) {
1171 		if ((unsigned long) port >= (unsigned long) p)
1172 			break;
1173 		slot = &p->rlist;
1174 	}
1175 
1176 	if (slot)
1177 		hlist_add_behind_rcu(&port->rlist, slot);
1178 	else
1179 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1180 }
1181 
1182 static void br_multicast_mark_router(struct net_bridge *br,
1183 				     struct net_bridge_port *port)
1184 {
1185 	unsigned long now = jiffies;
1186 
1187 	if (!port) {
1188 		if (br->multicast_router == 1)
1189 			mod_timer(&br->multicast_router_timer,
1190 				  now + br->multicast_querier_interval);
1191 		return;
1192 	}
1193 
1194 	if (port->multicast_router != 1)
1195 		return;
1196 
1197 	if (!hlist_unhashed(&port->rlist))
1198 		goto timer;
1199 
1200 	br_multicast_add_router(br, port);
1201 
1202 timer:
1203 	mod_timer(&port->multicast_router_timer,
1204 		  now + br->multicast_querier_interval);
1205 }
1206 
1207 static void br_multicast_query_received(struct net_bridge *br,
1208 					struct net_bridge_port *port,
1209 					struct bridge_mcast_other_query *query,
1210 					struct br_ip *saddr,
1211 					unsigned long max_delay)
1212 {
1213 	if (!br_multicast_select_querier(br, port, saddr))
1214 		return;
1215 
1216 	br_multicast_update_query_timer(br, query, max_delay);
1217 	br_multicast_mark_router(br, port);
1218 }
1219 
1220 static int br_ip4_multicast_query(struct net_bridge *br,
1221 				  struct net_bridge_port *port,
1222 				  struct sk_buff *skb,
1223 				  u16 vid)
1224 {
1225 	const struct iphdr *iph = ip_hdr(skb);
1226 	struct igmphdr *ih = igmp_hdr(skb);
1227 	struct net_bridge_mdb_entry *mp;
1228 	struct igmpv3_query *ih3;
1229 	struct net_bridge_port_group *p;
1230 	struct net_bridge_port_group __rcu **pp;
1231 	struct br_ip saddr;
1232 	unsigned long max_delay;
1233 	unsigned long now = jiffies;
1234 	__be32 group;
1235 	int err = 0;
1236 
1237 	spin_lock(&br->multicast_lock);
1238 	if (!netif_running(br->dev) ||
1239 	    (port && port->state == BR_STATE_DISABLED))
1240 		goto out;
1241 
1242 	group = ih->group;
1243 
1244 	if (skb->len == sizeof(*ih)) {
1245 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1246 
1247 		if (!max_delay) {
1248 			max_delay = 10 * HZ;
1249 			group = 0;
1250 		}
1251 	} else {
1252 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1253 			err = -EINVAL;
1254 			goto out;
1255 		}
1256 
1257 		ih3 = igmpv3_query_hdr(skb);
1258 		if (ih3->nsrcs)
1259 			goto out;
1260 
1261 		max_delay = ih3->code ?
1262 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1263 	}
1264 
1265 	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1266 	 * all-systems destination addresses (224.0.0.1) for general queries
1267 	 */
1268 	if (!group && iph->daddr != htonl(INADDR_ALLHOSTS_GROUP)) {
1269 		err = -EINVAL;
1270 		goto out;
1271 	}
1272 
1273 	if (!group) {
1274 		saddr.proto = htons(ETH_P_IP);
1275 		saddr.u.ip4 = iph->saddr;
1276 
1277 		br_multicast_query_received(br, port, &br->ip4_other_query,
1278 					    &saddr, max_delay);
1279 		goto out;
1280 	}
1281 
1282 	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1283 	if (!mp)
1284 		goto out;
1285 
1286 	max_delay *= br->multicast_last_member_count;
1287 
1288 	if (mp->mglist &&
1289 	    (timer_pending(&mp->timer) ?
1290 	     time_after(mp->timer.expires, now + max_delay) :
1291 	     try_to_del_timer_sync(&mp->timer) >= 0))
1292 		mod_timer(&mp->timer, now + max_delay);
1293 
1294 	for (pp = &mp->ports;
1295 	     (p = mlock_dereference(*pp, br)) != NULL;
1296 	     pp = &p->next) {
1297 		if (timer_pending(&p->timer) ?
1298 		    time_after(p->timer.expires, now + max_delay) :
1299 		    try_to_del_timer_sync(&p->timer) >= 0)
1300 			mod_timer(&p->timer, now + max_delay);
1301 	}
1302 
1303 out:
1304 	spin_unlock(&br->multicast_lock);
1305 	return err;
1306 }
1307 
1308 #if IS_ENABLED(CONFIG_IPV6)
1309 static int br_ip6_multicast_query(struct net_bridge *br,
1310 				  struct net_bridge_port *port,
1311 				  struct sk_buff *skb,
1312 				  u16 vid)
1313 {
1314 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1315 	struct mld_msg *mld;
1316 	struct net_bridge_mdb_entry *mp;
1317 	struct mld2_query *mld2q;
1318 	struct net_bridge_port_group *p;
1319 	struct net_bridge_port_group __rcu **pp;
1320 	struct br_ip saddr;
1321 	unsigned long max_delay;
1322 	unsigned long now = jiffies;
1323 	const struct in6_addr *group = NULL;
1324 	bool is_general_query;
1325 	int err = 0;
1326 
1327 	spin_lock(&br->multicast_lock);
1328 	if (!netif_running(br->dev) ||
1329 	    (port && port->state == BR_STATE_DISABLED))
1330 		goto out;
1331 
1332 	/* RFC2710+RFC3810 (MLDv1+MLDv2) require link-local source addresses */
1333 	if (!(ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1334 		err = -EINVAL;
1335 		goto out;
1336 	}
1337 
1338 	if (skb->len == sizeof(*mld)) {
1339 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1340 			err = -EINVAL;
1341 			goto out;
1342 		}
1343 		mld = (struct mld_msg *) icmp6_hdr(skb);
1344 		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1345 		if (max_delay)
1346 			group = &mld->mld_mca;
1347 	} else {
1348 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1349 			err = -EINVAL;
1350 			goto out;
1351 		}
1352 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1353 		if (!mld2q->mld2q_nsrcs)
1354 			group = &mld2q->mld2q_mca;
1355 
1356 		max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1357 	}
1358 
1359 	is_general_query = group && ipv6_addr_any(group);
1360 
1361 	/* RFC2710+RFC3810 (MLDv1+MLDv2) require the multicast link layer
1362 	 * all-nodes destination address (ff02::1) for general queries
1363 	 */
1364 	if (is_general_query && !ipv6_addr_is_ll_all_nodes(&ip6h->daddr)) {
1365 		err = -EINVAL;
1366 		goto out;
1367 	}
1368 
1369 	if (is_general_query) {
1370 		saddr.proto = htons(ETH_P_IPV6);
1371 		saddr.u.ip6 = ip6h->saddr;
1372 
1373 		br_multicast_query_received(br, port, &br->ip6_other_query,
1374 					    &saddr, max_delay);
1375 		goto out;
1376 	} else if (!group) {
1377 		goto out;
1378 	}
1379 
1380 	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1381 	if (!mp)
1382 		goto out;
1383 
1384 	max_delay *= br->multicast_last_member_count;
1385 	if (mp->mglist &&
1386 	    (timer_pending(&mp->timer) ?
1387 	     time_after(mp->timer.expires, now + max_delay) :
1388 	     try_to_del_timer_sync(&mp->timer) >= 0))
1389 		mod_timer(&mp->timer, now + max_delay);
1390 
1391 	for (pp = &mp->ports;
1392 	     (p = mlock_dereference(*pp, br)) != NULL;
1393 	     pp = &p->next) {
1394 		if (timer_pending(&p->timer) ?
1395 		    time_after(p->timer.expires, now + max_delay) :
1396 		    try_to_del_timer_sync(&p->timer) >= 0)
1397 			mod_timer(&p->timer, now + max_delay);
1398 	}
1399 
1400 out:
1401 	spin_unlock(&br->multicast_lock);
1402 	return err;
1403 }
1404 #endif
1405 
1406 static void
1407 br_multicast_leave_group(struct net_bridge *br,
1408 			 struct net_bridge_port *port,
1409 			 struct br_ip *group,
1410 			 struct bridge_mcast_other_query *other_query,
1411 			 struct bridge_mcast_own_query *own_query)
1412 {
1413 	struct net_bridge_mdb_htable *mdb;
1414 	struct net_bridge_mdb_entry *mp;
1415 	struct net_bridge_port_group *p;
1416 	unsigned long now;
1417 	unsigned long time;
1418 
1419 	spin_lock(&br->multicast_lock);
1420 	if (!netif_running(br->dev) ||
1421 	    (port && port->state == BR_STATE_DISABLED) ||
1422 	    timer_pending(&other_query->timer))
1423 		goto out;
1424 
1425 	mdb = mlock_dereference(br->mdb, br);
1426 	mp = br_mdb_ip_get(mdb, group);
1427 	if (!mp)
1428 		goto out;
1429 
1430 	if (br->multicast_querier) {
1431 		__br_multicast_send_query(br, port, &mp->addr);
1432 
1433 		time = jiffies + br->multicast_last_member_count *
1434 				 br->multicast_last_member_interval;
1435 
1436 		mod_timer(&own_query->timer, time);
1437 
1438 		for (p = mlock_dereference(mp->ports, br);
1439 		     p != NULL;
1440 		     p = mlock_dereference(p->next, br)) {
1441 			if (p->port != port)
1442 				continue;
1443 
1444 			if (!hlist_unhashed(&p->mglist) &&
1445 			    (timer_pending(&p->timer) ?
1446 			     time_after(p->timer.expires, time) :
1447 			     try_to_del_timer_sync(&p->timer) >= 0)) {
1448 				mod_timer(&p->timer, time);
1449 			}
1450 
1451 			break;
1452 		}
1453 	}
1454 
1455 	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1456 		struct net_bridge_port_group __rcu **pp;
1457 
1458 		for (pp = &mp->ports;
1459 		     (p = mlock_dereference(*pp, br)) != NULL;
1460 		     pp = &p->next) {
1461 			if (p->port != port)
1462 				continue;
1463 
1464 			rcu_assign_pointer(*pp, p->next);
1465 			hlist_del_init(&p->mglist);
1466 			del_timer(&p->timer);
1467 			call_rcu_bh(&p->rcu, br_multicast_free_pg);
1468 			br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1469 
1470 			if (!mp->ports && !mp->mglist &&
1471 			    netif_running(br->dev))
1472 				mod_timer(&mp->timer, jiffies);
1473 		}
1474 		goto out;
1475 	}
1476 
1477 	now = jiffies;
1478 	time = now + br->multicast_last_member_count *
1479 		     br->multicast_last_member_interval;
1480 
1481 	if (!port) {
1482 		if (mp->mglist &&
1483 		    (timer_pending(&mp->timer) ?
1484 		     time_after(mp->timer.expires, time) :
1485 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1486 			mod_timer(&mp->timer, time);
1487 		}
1488 
1489 		goto out;
1490 	}
1491 
1492 	for (p = mlock_dereference(mp->ports, br);
1493 	     p != NULL;
1494 	     p = mlock_dereference(p->next, br)) {
1495 		if (p->port != port)
1496 			continue;
1497 
1498 		if (!hlist_unhashed(&p->mglist) &&
1499 		    (timer_pending(&p->timer) ?
1500 		     time_after(p->timer.expires, time) :
1501 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1502 			mod_timer(&p->timer, time);
1503 		}
1504 
1505 		break;
1506 	}
1507 out:
1508 	spin_unlock(&br->multicast_lock);
1509 }
1510 
1511 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1512 					 struct net_bridge_port *port,
1513 					 __be32 group,
1514 					 __u16 vid)
1515 {
1516 	struct br_ip br_group;
1517 	struct bridge_mcast_own_query *own_query;
1518 
1519 	if (ipv4_is_local_multicast(group))
1520 		return;
1521 
1522 	own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1523 
1524 	br_group.u.ip4 = group;
1525 	br_group.proto = htons(ETH_P_IP);
1526 	br_group.vid = vid;
1527 
1528 	br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1529 				 own_query);
1530 }
1531 
1532 #if IS_ENABLED(CONFIG_IPV6)
1533 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1534 					 struct net_bridge_port *port,
1535 					 const struct in6_addr *group,
1536 					 __u16 vid)
1537 {
1538 	struct br_ip br_group;
1539 	struct bridge_mcast_own_query *own_query;
1540 
1541 	if (ipv6_addr_is_ll_all_nodes(group))
1542 		return;
1543 
1544 	own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1545 
1546 	br_group.u.ip6 = *group;
1547 	br_group.proto = htons(ETH_P_IPV6);
1548 	br_group.vid = vid;
1549 
1550 	br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1551 				 own_query);
1552 }
1553 #endif
1554 
1555 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1556 				 struct net_bridge_port *port,
1557 				 struct sk_buff *skb,
1558 				 u16 vid)
1559 {
1560 	struct sk_buff *skb2 = skb;
1561 	const struct iphdr *iph;
1562 	struct igmphdr *ih;
1563 	unsigned int len;
1564 	unsigned int offset;
1565 	int err;
1566 
1567 	/* We treat OOM as packet loss for now. */
1568 	if (!pskb_may_pull(skb, sizeof(*iph)))
1569 		return -EINVAL;
1570 
1571 	iph = ip_hdr(skb);
1572 
1573 	if (iph->ihl < 5 || iph->version != 4)
1574 		return -EINVAL;
1575 
1576 	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1577 		return -EINVAL;
1578 
1579 	iph = ip_hdr(skb);
1580 
1581 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1582 		return -EINVAL;
1583 
1584 	if (iph->protocol != IPPROTO_IGMP) {
1585 		if (!ipv4_is_local_multicast(iph->daddr))
1586 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1587 		return 0;
1588 	}
1589 
1590 	len = ntohs(iph->tot_len);
1591 	if (skb->len < len || len < ip_hdrlen(skb))
1592 		return -EINVAL;
1593 
1594 	if (skb->len > len) {
1595 		skb2 = skb_clone(skb, GFP_ATOMIC);
1596 		if (!skb2)
1597 			return -ENOMEM;
1598 
1599 		err = pskb_trim_rcsum(skb2, len);
1600 		if (err)
1601 			goto err_out;
1602 	}
1603 
1604 	len -= ip_hdrlen(skb2);
1605 	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1606 	__skb_pull(skb2, offset);
1607 	skb_reset_transport_header(skb2);
1608 
1609 	err = -EINVAL;
1610 	if (!pskb_may_pull(skb2, sizeof(*ih)))
1611 		goto out;
1612 
1613 	switch (skb2->ip_summed) {
1614 	case CHECKSUM_COMPLETE:
1615 		if (!csum_fold(skb2->csum))
1616 			break;
1617 		/* fall through */
1618 	case CHECKSUM_NONE:
1619 		skb2->csum = 0;
1620 		if (skb_checksum_complete(skb2))
1621 			goto out;
1622 	}
1623 
1624 	err = 0;
1625 
1626 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1627 	ih = igmp_hdr(skb2);
1628 
1629 	switch (ih->type) {
1630 	case IGMP_HOST_MEMBERSHIP_REPORT:
1631 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1632 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1633 		err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1634 		break;
1635 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1636 		err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
1637 		break;
1638 	case IGMP_HOST_MEMBERSHIP_QUERY:
1639 		err = br_ip4_multicast_query(br, port, skb2, vid);
1640 		break;
1641 	case IGMP_HOST_LEAVE_MESSAGE:
1642 		br_ip4_multicast_leave_group(br, port, ih->group, vid);
1643 		break;
1644 	}
1645 
1646 out:
1647 	__skb_push(skb2, offset);
1648 err_out:
1649 	if (skb2 != skb)
1650 		kfree_skb(skb2);
1651 	return err;
1652 }
1653 
1654 #if IS_ENABLED(CONFIG_IPV6)
1655 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1656 				 struct net_bridge_port *port,
1657 				 struct sk_buff *skb,
1658 				 u16 vid)
1659 {
1660 	struct sk_buff *skb2;
1661 	const struct ipv6hdr *ip6h;
1662 	u8 icmp6_type;
1663 	u8 nexthdr;
1664 	__be16 frag_off;
1665 	unsigned int len;
1666 	int offset;
1667 	int err;
1668 
1669 	if (!pskb_may_pull(skb, sizeof(*ip6h)))
1670 		return -EINVAL;
1671 
1672 	ip6h = ipv6_hdr(skb);
1673 
1674 	/*
1675 	 * We're interested in MLD messages only.
1676 	 *  - Version is 6
1677 	 *  - MLD has always Router Alert hop-by-hop option
1678 	 *  - But we do not support jumbrograms.
1679 	 */
1680 	if (ip6h->version != 6)
1681 		return 0;
1682 
1683 	/* Prevent flooding this packet if there is no listener present */
1684 	if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
1685 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1686 
1687 	if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
1688 	    ip6h->payload_len == 0)
1689 		return 0;
1690 
1691 	len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1692 	if (skb->len < len)
1693 		return -EINVAL;
1694 
1695 	nexthdr = ip6h->nexthdr;
1696 	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1697 
1698 	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1699 		return 0;
1700 
1701 	/* Okay, we found ICMPv6 header */
1702 	skb2 = skb_clone(skb, GFP_ATOMIC);
1703 	if (!skb2)
1704 		return -ENOMEM;
1705 
1706 	err = -EINVAL;
1707 	if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1708 		goto out;
1709 
1710 	len -= offset - skb_network_offset(skb2);
1711 
1712 	__skb_pull(skb2, offset);
1713 	skb_reset_transport_header(skb2);
1714 	skb_postpull_rcsum(skb2, skb_network_header(skb2),
1715 			   skb_network_header_len(skb2));
1716 
1717 	icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1718 
1719 	switch (icmp6_type) {
1720 	case ICMPV6_MGM_QUERY:
1721 	case ICMPV6_MGM_REPORT:
1722 	case ICMPV6_MGM_REDUCTION:
1723 	case ICMPV6_MLD2_REPORT:
1724 		break;
1725 	default:
1726 		err = 0;
1727 		goto out;
1728 	}
1729 
1730 	/* Okay, we found MLD message. Check further. */
1731 	if (skb2->len > len) {
1732 		err = pskb_trim_rcsum(skb2, len);
1733 		if (err)
1734 			goto out;
1735 		err = -EINVAL;
1736 	}
1737 
1738 	ip6h = ipv6_hdr(skb2);
1739 
1740 	switch (skb2->ip_summed) {
1741 	case CHECKSUM_COMPLETE:
1742 		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1743 					IPPROTO_ICMPV6, skb2->csum))
1744 			break;
1745 		/*FALLTHROUGH*/
1746 	case CHECKSUM_NONE:
1747 		skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1748 							&ip6h->daddr,
1749 							skb2->len,
1750 							IPPROTO_ICMPV6, 0));
1751 		if (__skb_checksum_complete(skb2))
1752 			goto out;
1753 	}
1754 
1755 	err = 0;
1756 
1757 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1758 
1759 	switch (icmp6_type) {
1760 	case ICMPV6_MGM_REPORT:
1761 	    {
1762 		struct mld_msg *mld;
1763 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1764 			err = -EINVAL;
1765 			goto out;
1766 		}
1767 		mld = (struct mld_msg *)skb_transport_header(skb2);
1768 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1769 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1770 		break;
1771 	    }
1772 	case ICMPV6_MLD2_REPORT:
1773 		err = br_ip6_multicast_mld2_report(br, port, skb2, vid);
1774 		break;
1775 	case ICMPV6_MGM_QUERY:
1776 		err = br_ip6_multicast_query(br, port, skb2, vid);
1777 		break;
1778 	case ICMPV6_MGM_REDUCTION:
1779 	    {
1780 		struct mld_msg *mld;
1781 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1782 			err = -EINVAL;
1783 			goto out;
1784 		}
1785 		mld = (struct mld_msg *)skb_transport_header(skb2);
1786 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1787 	    }
1788 	}
1789 
1790 out:
1791 	kfree_skb(skb2);
1792 	return err;
1793 }
1794 #endif
1795 
1796 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1797 		     struct sk_buff *skb, u16 vid)
1798 {
1799 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1800 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1801 
1802 	if (br->multicast_disabled)
1803 		return 0;
1804 
1805 	switch (skb->protocol) {
1806 	case htons(ETH_P_IP):
1807 		return br_multicast_ipv4_rcv(br, port, skb, vid);
1808 #if IS_ENABLED(CONFIG_IPV6)
1809 	case htons(ETH_P_IPV6):
1810 		return br_multicast_ipv6_rcv(br, port, skb, vid);
1811 #endif
1812 	}
1813 
1814 	return 0;
1815 }
1816 
1817 static void br_multicast_query_expired(struct net_bridge *br,
1818 				       struct bridge_mcast_own_query *query,
1819 				       struct bridge_mcast_querier *querier)
1820 {
1821 	spin_lock(&br->multicast_lock);
1822 	if (query->startup_sent < br->multicast_startup_query_count)
1823 		query->startup_sent++;
1824 
1825 	RCU_INIT_POINTER(querier, NULL);
1826 	br_multicast_send_query(br, NULL, query);
1827 	spin_unlock(&br->multicast_lock);
1828 }
1829 
1830 static void br_ip4_multicast_query_expired(unsigned long data)
1831 {
1832 	struct net_bridge *br = (void *)data;
1833 
1834 	br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1835 }
1836 
1837 #if IS_ENABLED(CONFIG_IPV6)
1838 static void br_ip6_multicast_query_expired(unsigned long data)
1839 {
1840 	struct net_bridge *br = (void *)data;
1841 
1842 	br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1843 }
1844 #endif
1845 
1846 void br_multicast_init(struct net_bridge *br)
1847 {
1848 	br->hash_elasticity = 4;
1849 	br->hash_max = 512;
1850 
1851 	br->multicast_router = 1;
1852 	br->multicast_querier = 0;
1853 	br->multicast_query_use_ifaddr = 0;
1854 	br->multicast_last_member_count = 2;
1855 	br->multicast_startup_query_count = 2;
1856 
1857 	br->multicast_last_member_interval = HZ;
1858 	br->multicast_query_response_interval = 10 * HZ;
1859 	br->multicast_startup_query_interval = 125 * HZ / 4;
1860 	br->multicast_query_interval = 125 * HZ;
1861 	br->multicast_querier_interval = 255 * HZ;
1862 	br->multicast_membership_interval = 260 * HZ;
1863 
1864 	br->ip4_other_query.delay_time = 0;
1865 	br->ip4_querier.port = NULL;
1866 #if IS_ENABLED(CONFIG_IPV6)
1867 	br->ip6_other_query.delay_time = 0;
1868 	br->ip6_querier.port = NULL;
1869 #endif
1870 
1871 	spin_lock_init(&br->multicast_lock);
1872 	setup_timer(&br->multicast_router_timer,
1873 		    br_multicast_local_router_expired, 0);
1874 	setup_timer(&br->ip4_other_query.timer,
1875 		    br_ip4_multicast_querier_expired, (unsigned long)br);
1876 	setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1877 		    (unsigned long)br);
1878 #if IS_ENABLED(CONFIG_IPV6)
1879 	setup_timer(&br->ip6_other_query.timer,
1880 		    br_ip6_multicast_querier_expired, (unsigned long)br);
1881 	setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1882 		    (unsigned long)br);
1883 #endif
1884 }
1885 
1886 static void __br_multicast_open(struct net_bridge *br,
1887 				struct bridge_mcast_own_query *query)
1888 {
1889 	query->startup_sent = 0;
1890 
1891 	if (br->multicast_disabled)
1892 		return;
1893 
1894 	mod_timer(&query->timer, jiffies);
1895 }
1896 
1897 void br_multicast_open(struct net_bridge *br)
1898 {
1899 	__br_multicast_open(br, &br->ip4_own_query);
1900 #if IS_ENABLED(CONFIG_IPV6)
1901 	__br_multicast_open(br, &br->ip6_own_query);
1902 #endif
1903 }
1904 
1905 void br_multicast_stop(struct net_bridge *br)
1906 {
1907 	struct net_bridge_mdb_htable *mdb;
1908 	struct net_bridge_mdb_entry *mp;
1909 	struct hlist_node *n;
1910 	u32 ver;
1911 	int i;
1912 
1913 	del_timer_sync(&br->multicast_router_timer);
1914 	del_timer_sync(&br->ip4_other_query.timer);
1915 	del_timer_sync(&br->ip4_own_query.timer);
1916 #if IS_ENABLED(CONFIG_IPV6)
1917 	del_timer_sync(&br->ip6_other_query.timer);
1918 	del_timer_sync(&br->ip6_own_query.timer);
1919 #endif
1920 
1921 	spin_lock_bh(&br->multicast_lock);
1922 	mdb = mlock_dereference(br->mdb, br);
1923 	if (!mdb)
1924 		goto out;
1925 
1926 	br->mdb = NULL;
1927 
1928 	ver = mdb->ver;
1929 	for (i = 0; i < mdb->max; i++) {
1930 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1931 					  hlist[ver]) {
1932 			del_timer(&mp->timer);
1933 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1934 		}
1935 	}
1936 
1937 	if (mdb->old) {
1938 		spin_unlock_bh(&br->multicast_lock);
1939 		rcu_barrier_bh();
1940 		spin_lock_bh(&br->multicast_lock);
1941 		WARN_ON(mdb->old);
1942 	}
1943 
1944 	mdb->old = mdb;
1945 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1946 
1947 out:
1948 	spin_unlock_bh(&br->multicast_lock);
1949 }
1950 
1951 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1952 {
1953 	int err = -ENOENT;
1954 
1955 	spin_lock_bh(&br->multicast_lock);
1956 	if (!netif_running(br->dev))
1957 		goto unlock;
1958 
1959 	switch (val) {
1960 	case 0:
1961 	case 2:
1962 		del_timer(&br->multicast_router_timer);
1963 		/* fall through */
1964 	case 1:
1965 		br->multicast_router = val;
1966 		err = 0;
1967 		break;
1968 
1969 	default:
1970 		err = -EINVAL;
1971 		break;
1972 	}
1973 
1974 unlock:
1975 	spin_unlock_bh(&br->multicast_lock);
1976 
1977 	return err;
1978 }
1979 
1980 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1981 {
1982 	struct net_bridge *br = p->br;
1983 	int err = -ENOENT;
1984 
1985 	spin_lock(&br->multicast_lock);
1986 	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1987 		goto unlock;
1988 
1989 	switch (val) {
1990 	case 0:
1991 	case 1:
1992 	case 2:
1993 		p->multicast_router = val;
1994 		err = 0;
1995 
1996 		if (val < 2 && !hlist_unhashed(&p->rlist))
1997 			hlist_del_init_rcu(&p->rlist);
1998 
1999 		if (val == 1)
2000 			break;
2001 
2002 		del_timer(&p->multicast_router_timer);
2003 
2004 		if (val == 0)
2005 			break;
2006 
2007 		br_multicast_add_router(br, p);
2008 		break;
2009 
2010 	default:
2011 		err = -EINVAL;
2012 		break;
2013 	}
2014 
2015 unlock:
2016 	spin_unlock(&br->multicast_lock);
2017 
2018 	return err;
2019 }
2020 
2021 static void br_multicast_start_querier(struct net_bridge *br,
2022 				       struct bridge_mcast_own_query *query)
2023 {
2024 	struct net_bridge_port *port;
2025 
2026 	__br_multicast_open(br, query);
2027 
2028 	list_for_each_entry(port, &br->port_list, list) {
2029 		if (port->state == BR_STATE_DISABLED ||
2030 		    port->state == BR_STATE_BLOCKING)
2031 			continue;
2032 
2033 		if (query == &br->ip4_own_query)
2034 			br_multicast_enable(&port->ip4_own_query);
2035 #if IS_ENABLED(CONFIG_IPV6)
2036 		else
2037 			br_multicast_enable(&port->ip6_own_query);
2038 #endif
2039 	}
2040 }
2041 
2042 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
2043 {
2044 	int err = 0;
2045 	struct net_bridge_mdb_htable *mdb;
2046 
2047 	spin_lock_bh(&br->multicast_lock);
2048 	if (br->multicast_disabled == !val)
2049 		goto unlock;
2050 
2051 	br->multicast_disabled = !val;
2052 	if (br->multicast_disabled)
2053 		goto unlock;
2054 
2055 	if (!netif_running(br->dev))
2056 		goto unlock;
2057 
2058 	mdb = mlock_dereference(br->mdb, br);
2059 	if (mdb) {
2060 		if (mdb->old) {
2061 			err = -EEXIST;
2062 rollback:
2063 			br->multicast_disabled = !!val;
2064 			goto unlock;
2065 		}
2066 
2067 		err = br_mdb_rehash(&br->mdb, mdb->max,
2068 				    br->hash_elasticity);
2069 		if (err)
2070 			goto rollback;
2071 	}
2072 
2073 	br_multicast_start_querier(br, &br->ip4_own_query);
2074 #if IS_ENABLED(CONFIG_IPV6)
2075 	br_multicast_start_querier(br, &br->ip6_own_query);
2076 #endif
2077 
2078 unlock:
2079 	spin_unlock_bh(&br->multicast_lock);
2080 
2081 	return err;
2082 }
2083 
2084 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
2085 {
2086 	unsigned long max_delay;
2087 
2088 	val = !!val;
2089 
2090 	spin_lock_bh(&br->multicast_lock);
2091 	if (br->multicast_querier == val)
2092 		goto unlock;
2093 
2094 	br->multicast_querier = val;
2095 	if (!val)
2096 		goto unlock;
2097 
2098 	max_delay = br->multicast_query_response_interval;
2099 
2100 	if (!timer_pending(&br->ip4_other_query.timer))
2101 		br->ip4_other_query.delay_time = jiffies + max_delay;
2102 
2103 	br_multicast_start_querier(br, &br->ip4_own_query);
2104 
2105 #if IS_ENABLED(CONFIG_IPV6)
2106 	if (!timer_pending(&br->ip6_other_query.timer))
2107 		br->ip6_other_query.delay_time = jiffies + max_delay;
2108 
2109 	br_multicast_start_querier(br, &br->ip6_own_query);
2110 #endif
2111 
2112 unlock:
2113 	spin_unlock_bh(&br->multicast_lock);
2114 
2115 	return 0;
2116 }
2117 
2118 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2119 {
2120 	int err = -ENOENT;
2121 	u32 old;
2122 	struct net_bridge_mdb_htable *mdb;
2123 
2124 	spin_lock_bh(&br->multicast_lock);
2125 	if (!netif_running(br->dev))
2126 		goto unlock;
2127 
2128 	err = -EINVAL;
2129 	if (!is_power_of_2(val))
2130 		goto unlock;
2131 
2132 	mdb = mlock_dereference(br->mdb, br);
2133 	if (mdb && val < mdb->size)
2134 		goto unlock;
2135 
2136 	err = 0;
2137 
2138 	old = br->hash_max;
2139 	br->hash_max = val;
2140 
2141 	if (mdb) {
2142 		if (mdb->old) {
2143 			err = -EEXIST;
2144 rollback:
2145 			br->hash_max = old;
2146 			goto unlock;
2147 		}
2148 
2149 		err = br_mdb_rehash(&br->mdb, br->hash_max,
2150 				    br->hash_elasticity);
2151 		if (err)
2152 			goto rollback;
2153 	}
2154 
2155 unlock:
2156 	spin_unlock_bh(&br->multicast_lock);
2157 
2158 	return err;
2159 }
2160 
2161 /**
2162  * br_multicast_list_adjacent - Returns snooped multicast addresses
2163  * @dev:	The bridge port adjacent to which to retrieve addresses
2164  * @br_ip_list:	The list to store found, snooped multicast IP addresses in
2165  *
2166  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2167  * snooping feature on all bridge ports of dev's bridge device, excluding
2168  * the addresses from dev itself.
2169  *
2170  * Returns the number of items added to br_ip_list.
2171  *
2172  * Notes:
2173  * - br_ip_list needs to be initialized by caller
2174  * - br_ip_list might contain duplicates in the end
2175  *   (needs to be taken care of by caller)
2176  * - br_ip_list needs to be freed by caller
2177  */
2178 int br_multicast_list_adjacent(struct net_device *dev,
2179 			       struct list_head *br_ip_list)
2180 {
2181 	struct net_bridge *br;
2182 	struct net_bridge_port *port;
2183 	struct net_bridge_port_group *group;
2184 	struct br_ip_list *entry;
2185 	int count = 0;
2186 
2187 	rcu_read_lock();
2188 	if (!br_ip_list || !br_port_exists(dev))
2189 		goto unlock;
2190 
2191 	port = br_port_get_rcu(dev);
2192 	if (!port || !port->br)
2193 		goto unlock;
2194 
2195 	br = port->br;
2196 
2197 	list_for_each_entry_rcu(port, &br->port_list, list) {
2198 		if (!port->dev || port->dev == dev)
2199 			continue;
2200 
2201 		hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2202 			entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2203 			if (!entry)
2204 				goto unlock;
2205 
2206 			entry->addr = group->addr;
2207 			list_add(&entry->list, br_ip_list);
2208 			count++;
2209 		}
2210 	}
2211 
2212 unlock:
2213 	rcu_read_unlock();
2214 	return count;
2215 }
2216 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2217 
2218 /**
2219  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2220  * @dev: The bridge port providing the bridge on which to check for a querier
2221  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2222  *
2223  * Checks whether the given interface has a bridge on top and if so returns
2224  * true if a valid querier exists anywhere on the bridged link layer.
2225  * Otherwise returns false.
2226  */
2227 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2228 {
2229 	struct net_bridge *br;
2230 	struct net_bridge_port *port;
2231 	struct ethhdr eth;
2232 	bool ret = false;
2233 
2234 	rcu_read_lock();
2235 	if (!br_port_exists(dev))
2236 		goto unlock;
2237 
2238 	port = br_port_get_rcu(dev);
2239 	if (!port || !port->br)
2240 		goto unlock;
2241 
2242 	br = port->br;
2243 
2244 	memset(&eth, 0, sizeof(eth));
2245 	eth.h_proto = htons(proto);
2246 
2247 	ret = br_multicast_querier_exists(br, &eth);
2248 
2249 unlock:
2250 	rcu_read_unlock();
2251 	return ret;
2252 }
2253 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2254 
2255 /**
2256  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2257  * @dev: The bridge port adjacent to which to check for a querier
2258  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2259  *
2260  * Checks whether the given interface has a bridge on top and if so returns
2261  * true if a selected querier is behind one of the other ports of this
2262  * bridge. Otherwise returns false.
2263  */
2264 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2265 {
2266 	struct net_bridge *br;
2267 	struct net_bridge_port *port;
2268 	bool ret = false;
2269 
2270 	rcu_read_lock();
2271 	if (!br_port_exists(dev))
2272 		goto unlock;
2273 
2274 	port = br_port_get_rcu(dev);
2275 	if (!port || !port->br)
2276 		goto unlock;
2277 
2278 	br = port->br;
2279 
2280 	switch (proto) {
2281 	case ETH_P_IP:
2282 		if (!timer_pending(&br->ip4_other_query.timer) ||
2283 		    rcu_dereference(br->ip4_querier.port) == port)
2284 			goto unlock;
2285 		break;
2286 #if IS_ENABLED(CONFIG_IPV6)
2287 	case ETH_P_IPV6:
2288 		if (!timer_pending(&br->ip6_other_query.timer) ||
2289 		    rcu_dereference(br->ip6_querier.port) == port)
2290 			goto unlock;
2291 		break;
2292 #endif
2293 	default:
2294 		goto unlock;
2295 	}
2296 
2297 	ret = true;
2298 unlock:
2299 	rcu_read_unlock();
2300 	return ret;
2301 }
2302 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);
2303