xref: /openbmc/linux/net/bridge/br_multicast.c (revision 7b6d864b)
1 /*
2  * Bridge multicast support.
3  *
4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <linux/err.h>
14 #include <linux/if_ether.h>
15 #include <linux/igmp.h>
16 #include <linux/jhash.h>
17 #include <linux/kernel.h>
18 #include <linux/log2.h>
19 #include <linux/netdevice.h>
20 #include <linux/netfilter_bridge.h>
21 #include <linux/random.h>
22 #include <linux/rculist.h>
23 #include <linux/skbuff.h>
24 #include <linux/slab.h>
25 #include <linux/timer.h>
26 #include <net/ip.h>
27 #if IS_ENABLED(CONFIG_IPV6)
28 #include <net/ipv6.h>
29 #include <net/mld.h>
30 #include <net/ip6_checksum.h>
31 #endif
32 
33 #include "br_private.h"
34 
35 static void br_multicast_start_querier(struct net_bridge *br);
36 unsigned int br_mdb_rehash_seq;
37 
38 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
39 {
40 	if (a->proto != b->proto)
41 		return 0;
42 	if (a->vid != b->vid)
43 		return 0;
44 	switch (a->proto) {
45 	case htons(ETH_P_IP):
46 		return a->u.ip4 == b->u.ip4;
47 #if IS_ENABLED(CONFIG_IPV6)
48 	case htons(ETH_P_IPV6):
49 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
50 #endif
51 	}
52 	return 0;
53 }
54 
55 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
56 				__u16 vid)
57 {
58 	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
59 }
60 
61 #if IS_ENABLED(CONFIG_IPV6)
62 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
63 				const struct in6_addr *ip,
64 				__u16 vid)
65 {
66 	return jhash_2words(ipv6_addr_hash(ip), vid,
67 			    mdb->secret) & (mdb->max - 1);
68 }
69 #endif
70 
71 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
72 			     struct br_ip *ip)
73 {
74 	switch (ip->proto) {
75 	case htons(ETH_P_IP):
76 		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
77 #if IS_ENABLED(CONFIG_IPV6)
78 	case htons(ETH_P_IPV6):
79 		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
80 #endif
81 	}
82 	return 0;
83 }
84 
85 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
86 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
87 {
88 	struct net_bridge_mdb_entry *mp;
89 
90 	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
91 		if (br_ip_equal(&mp->addr, dst))
92 			return mp;
93 	}
94 
95 	return NULL;
96 }
97 
98 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
99 					   struct br_ip *dst)
100 {
101 	if (!mdb)
102 		return NULL;
103 
104 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
105 }
106 
107 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
108 	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
109 {
110 	struct br_ip br_dst;
111 
112 	br_dst.u.ip4 = dst;
113 	br_dst.proto = htons(ETH_P_IP);
114 	br_dst.vid = vid;
115 
116 	return br_mdb_ip_get(mdb, &br_dst);
117 }
118 
119 #if IS_ENABLED(CONFIG_IPV6)
120 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
121 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
122 	__u16 vid)
123 {
124 	struct br_ip br_dst;
125 
126 	br_dst.u.ip6 = *dst;
127 	br_dst.proto = htons(ETH_P_IPV6);
128 	br_dst.vid = vid;
129 
130 	return br_mdb_ip_get(mdb, &br_dst);
131 }
132 #endif
133 
134 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
135 					struct sk_buff *skb, u16 vid)
136 {
137 	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
138 	struct br_ip ip;
139 
140 	if (br->multicast_disabled)
141 		return NULL;
142 
143 	if (BR_INPUT_SKB_CB(skb)->igmp)
144 		return NULL;
145 
146 	ip.proto = skb->protocol;
147 	ip.vid = vid;
148 
149 	switch (skb->protocol) {
150 	case htons(ETH_P_IP):
151 		ip.u.ip4 = ip_hdr(skb)->daddr;
152 		break;
153 #if IS_ENABLED(CONFIG_IPV6)
154 	case htons(ETH_P_IPV6):
155 		ip.u.ip6 = ipv6_hdr(skb)->daddr;
156 		break;
157 #endif
158 	default:
159 		return NULL;
160 	}
161 
162 	return br_mdb_ip_get(mdb, &ip);
163 }
164 
165 static void br_mdb_free(struct rcu_head *head)
166 {
167 	struct net_bridge_mdb_htable *mdb =
168 		container_of(head, struct net_bridge_mdb_htable, rcu);
169 	struct net_bridge_mdb_htable *old = mdb->old;
170 
171 	mdb->old = NULL;
172 	kfree(old->mhash);
173 	kfree(old);
174 }
175 
176 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
177 		       struct net_bridge_mdb_htable *old,
178 		       int elasticity)
179 {
180 	struct net_bridge_mdb_entry *mp;
181 	int maxlen;
182 	int len;
183 	int i;
184 
185 	for (i = 0; i < old->max; i++)
186 		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
187 			hlist_add_head(&mp->hlist[new->ver],
188 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
189 
190 	if (!elasticity)
191 		return 0;
192 
193 	maxlen = 0;
194 	for (i = 0; i < new->max; i++) {
195 		len = 0;
196 		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
197 			len++;
198 		if (len > maxlen)
199 			maxlen = len;
200 	}
201 
202 	return maxlen > elasticity ? -EINVAL : 0;
203 }
204 
205 void br_multicast_free_pg(struct rcu_head *head)
206 {
207 	struct net_bridge_port_group *p =
208 		container_of(head, struct net_bridge_port_group, rcu);
209 
210 	kfree(p);
211 }
212 
213 static void br_multicast_free_group(struct rcu_head *head)
214 {
215 	struct net_bridge_mdb_entry *mp =
216 		container_of(head, struct net_bridge_mdb_entry, rcu);
217 
218 	kfree(mp);
219 }
220 
221 static void br_multicast_group_expired(unsigned long data)
222 {
223 	struct net_bridge_mdb_entry *mp = (void *)data;
224 	struct net_bridge *br = mp->br;
225 	struct net_bridge_mdb_htable *mdb;
226 
227 	spin_lock(&br->multicast_lock);
228 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
229 		goto out;
230 
231 	mp->mglist = false;
232 
233 	if (mp->ports)
234 		goto out;
235 
236 	mdb = mlock_dereference(br->mdb, br);
237 
238 	hlist_del_rcu(&mp->hlist[mdb->ver]);
239 	mdb->size--;
240 
241 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
242 
243 out:
244 	spin_unlock(&br->multicast_lock);
245 }
246 
247 static void br_multicast_del_pg(struct net_bridge *br,
248 				struct net_bridge_port_group *pg)
249 {
250 	struct net_bridge_mdb_htable *mdb;
251 	struct net_bridge_mdb_entry *mp;
252 	struct net_bridge_port_group *p;
253 	struct net_bridge_port_group __rcu **pp;
254 
255 	mdb = mlock_dereference(br->mdb, br);
256 
257 	mp = br_mdb_ip_get(mdb, &pg->addr);
258 	if (WARN_ON(!mp))
259 		return;
260 
261 	for (pp = &mp->ports;
262 	     (p = mlock_dereference(*pp, br)) != NULL;
263 	     pp = &p->next) {
264 		if (p != pg)
265 			continue;
266 
267 		rcu_assign_pointer(*pp, p->next);
268 		hlist_del_init(&p->mglist);
269 		del_timer(&p->timer);
270 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
271 
272 		if (!mp->ports && !mp->mglist &&
273 		    netif_running(br->dev))
274 			mod_timer(&mp->timer, jiffies);
275 
276 		return;
277 	}
278 
279 	WARN_ON(1);
280 }
281 
282 static void br_multicast_port_group_expired(unsigned long data)
283 {
284 	struct net_bridge_port_group *pg = (void *)data;
285 	struct net_bridge *br = pg->port->br;
286 
287 	spin_lock(&br->multicast_lock);
288 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
289 	    hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
290 		goto out;
291 
292 	br_multicast_del_pg(br, pg);
293 
294 out:
295 	spin_unlock(&br->multicast_lock);
296 }
297 
298 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
299 			 int elasticity)
300 {
301 	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
302 	struct net_bridge_mdb_htable *mdb;
303 	int err;
304 
305 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
306 	if (!mdb)
307 		return -ENOMEM;
308 
309 	mdb->max = max;
310 	mdb->old = old;
311 
312 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
313 	if (!mdb->mhash) {
314 		kfree(mdb);
315 		return -ENOMEM;
316 	}
317 
318 	mdb->size = old ? old->size : 0;
319 	mdb->ver = old ? old->ver ^ 1 : 0;
320 
321 	if (!old || elasticity)
322 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
323 	else
324 		mdb->secret = old->secret;
325 
326 	if (!old)
327 		goto out;
328 
329 	err = br_mdb_copy(mdb, old, elasticity);
330 	if (err) {
331 		kfree(mdb->mhash);
332 		kfree(mdb);
333 		return err;
334 	}
335 
336 	br_mdb_rehash_seq++;
337 	call_rcu_bh(&mdb->rcu, br_mdb_free);
338 
339 out:
340 	rcu_assign_pointer(*mdbp, mdb);
341 
342 	return 0;
343 }
344 
345 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
346 						    __be32 group)
347 {
348 	struct sk_buff *skb;
349 	struct igmphdr *ih;
350 	struct ethhdr *eth;
351 	struct iphdr *iph;
352 
353 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
354 						 sizeof(*ih) + 4);
355 	if (!skb)
356 		goto out;
357 
358 	skb->protocol = htons(ETH_P_IP);
359 
360 	skb_reset_mac_header(skb);
361 	eth = eth_hdr(skb);
362 
363 	memcpy(eth->h_source, br->dev->dev_addr, 6);
364 	eth->h_dest[0] = 1;
365 	eth->h_dest[1] = 0;
366 	eth->h_dest[2] = 0x5e;
367 	eth->h_dest[3] = 0;
368 	eth->h_dest[4] = 0;
369 	eth->h_dest[5] = 1;
370 	eth->h_proto = htons(ETH_P_IP);
371 	skb_put(skb, sizeof(*eth));
372 
373 	skb_set_network_header(skb, skb->len);
374 	iph = ip_hdr(skb);
375 
376 	iph->version = 4;
377 	iph->ihl = 6;
378 	iph->tos = 0xc0;
379 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
380 	iph->id = 0;
381 	iph->frag_off = htons(IP_DF);
382 	iph->ttl = 1;
383 	iph->protocol = IPPROTO_IGMP;
384 	iph->saddr = 0;
385 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
386 	((u8 *)&iph[1])[0] = IPOPT_RA;
387 	((u8 *)&iph[1])[1] = 4;
388 	((u8 *)&iph[1])[2] = 0;
389 	((u8 *)&iph[1])[3] = 0;
390 	ip_send_check(iph);
391 	skb_put(skb, 24);
392 
393 	skb_set_transport_header(skb, skb->len);
394 	ih = igmp_hdr(skb);
395 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
396 	ih->code = (group ? br->multicast_last_member_interval :
397 			    br->multicast_query_response_interval) /
398 		   (HZ / IGMP_TIMER_SCALE);
399 	ih->group = group;
400 	ih->csum = 0;
401 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
402 	skb_put(skb, sizeof(*ih));
403 
404 	__skb_pull(skb, sizeof(*eth));
405 
406 out:
407 	return skb;
408 }
409 
410 #if IS_ENABLED(CONFIG_IPV6)
411 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
412 						    const struct in6_addr *group)
413 {
414 	struct sk_buff *skb;
415 	struct ipv6hdr *ip6h;
416 	struct mld_msg *mldq;
417 	struct ethhdr *eth;
418 	u8 *hopopt;
419 	unsigned long interval;
420 
421 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
422 						 8 + sizeof(*mldq));
423 	if (!skb)
424 		goto out;
425 
426 	skb->protocol = htons(ETH_P_IPV6);
427 
428 	/* Ethernet header */
429 	skb_reset_mac_header(skb);
430 	eth = eth_hdr(skb);
431 
432 	memcpy(eth->h_source, br->dev->dev_addr, 6);
433 	eth->h_proto = htons(ETH_P_IPV6);
434 	skb_put(skb, sizeof(*eth));
435 
436 	/* IPv6 header + HbH option */
437 	skb_set_network_header(skb, skb->len);
438 	ip6h = ipv6_hdr(skb);
439 
440 	*(__force __be32 *)ip6h = htonl(0x60000000);
441 	ip6h->payload_len = htons(8 + sizeof(*mldq));
442 	ip6h->nexthdr = IPPROTO_HOPOPTS;
443 	ip6h->hop_limit = 1;
444 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
445 	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
446 			       &ip6h->saddr)) {
447 		kfree_skb(skb);
448 		return NULL;
449 	}
450 	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
451 
452 	hopopt = (u8 *)(ip6h + 1);
453 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
454 	hopopt[1] = 0;				/* length of HbH */
455 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
456 	hopopt[3] = 2;				/* Length of RA Option */
457 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
458 	hopopt[5] = 0;
459 	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
460 	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
461 
462 	skb_put(skb, sizeof(*ip6h) + 8);
463 
464 	/* ICMPv6 */
465 	skb_set_transport_header(skb, skb->len);
466 	mldq = (struct mld_msg *) icmp6_hdr(skb);
467 
468 	interval = ipv6_addr_any(group) ?
469 			br->multicast_query_response_interval :
470 			br->multicast_last_member_interval;
471 
472 	mldq->mld_type = ICMPV6_MGM_QUERY;
473 	mldq->mld_code = 0;
474 	mldq->mld_cksum = 0;
475 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
476 	mldq->mld_reserved = 0;
477 	mldq->mld_mca = *group;
478 
479 	/* checksum */
480 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
481 					  sizeof(*mldq), IPPROTO_ICMPV6,
482 					  csum_partial(mldq,
483 						       sizeof(*mldq), 0));
484 	skb_put(skb, sizeof(*mldq));
485 
486 	__skb_pull(skb, sizeof(*eth));
487 
488 out:
489 	return skb;
490 }
491 #endif
492 
493 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
494 						struct br_ip *addr)
495 {
496 	switch (addr->proto) {
497 	case htons(ETH_P_IP):
498 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
499 #if IS_ENABLED(CONFIG_IPV6)
500 	case htons(ETH_P_IPV6):
501 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
502 #endif
503 	}
504 	return NULL;
505 }
506 
507 static struct net_bridge_mdb_entry *br_multicast_get_group(
508 	struct net_bridge *br, struct net_bridge_port *port,
509 	struct br_ip *group, int hash)
510 {
511 	struct net_bridge_mdb_htable *mdb;
512 	struct net_bridge_mdb_entry *mp;
513 	unsigned int count = 0;
514 	unsigned int max;
515 	int elasticity;
516 	int err;
517 
518 	mdb = rcu_dereference_protected(br->mdb, 1);
519 	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
520 		count++;
521 		if (unlikely(br_ip_equal(group, &mp->addr)))
522 			return mp;
523 	}
524 
525 	elasticity = 0;
526 	max = mdb->max;
527 
528 	if (unlikely(count > br->hash_elasticity && count)) {
529 		if (net_ratelimit())
530 			br_info(br, "Multicast hash table "
531 				"chain limit reached: %s\n",
532 				port ? port->dev->name : br->dev->name);
533 
534 		elasticity = br->hash_elasticity;
535 	}
536 
537 	if (mdb->size >= max) {
538 		max *= 2;
539 		if (unlikely(max > br->hash_max)) {
540 			br_warn(br, "Multicast hash table maximum of %d "
541 				"reached, disabling snooping: %s\n",
542 				br->hash_max,
543 				port ? port->dev->name : br->dev->name);
544 			err = -E2BIG;
545 disable:
546 			br->multicast_disabled = 1;
547 			goto err;
548 		}
549 	}
550 
551 	if (max > mdb->max || elasticity) {
552 		if (mdb->old) {
553 			if (net_ratelimit())
554 				br_info(br, "Multicast hash table "
555 					"on fire: %s\n",
556 					port ? port->dev->name : br->dev->name);
557 			err = -EEXIST;
558 			goto err;
559 		}
560 
561 		err = br_mdb_rehash(&br->mdb, max, elasticity);
562 		if (err) {
563 			br_warn(br, "Cannot rehash multicast "
564 				"hash table, disabling snooping: %s, %d, %d\n",
565 				port ? port->dev->name : br->dev->name,
566 				mdb->size, err);
567 			goto disable;
568 		}
569 
570 		err = -EAGAIN;
571 		goto err;
572 	}
573 
574 	return NULL;
575 
576 err:
577 	mp = ERR_PTR(err);
578 	return mp;
579 }
580 
581 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
582 	struct net_bridge_port *port, struct br_ip *group)
583 {
584 	struct net_bridge_mdb_htable *mdb;
585 	struct net_bridge_mdb_entry *mp;
586 	int hash;
587 	int err;
588 
589 	mdb = rcu_dereference_protected(br->mdb, 1);
590 	if (!mdb) {
591 		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
592 		if (err)
593 			return ERR_PTR(err);
594 		goto rehash;
595 	}
596 
597 	hash = br_ip_hash(mdb, group);
598 	mp = br_multicast_get_group(br, port, group, hash);
599 	switch (PTR_ERR(mp)) {
600 	case 0:
601 		break;
602 
603 	case -EAGAIN:
604 rehash:
605 		mdb = rcu_dereference_protected(br->mdb, 1);
606 		hash = br_ip_hash(mdb, group);
607 		break;
608 
609 	default:
610 		goto out;
611 	}
612 
613 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
614 	if (unlikely(!mp))
615 		return ERR_PTR(-ENOMEM);
616 
617 	mp->br = br;
618 	mp->addr = *group;
619 	setup_timer(&mp->timer, br_multicast_group_expired,
620 		    (unsigned long)mp);
621 
622 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
623 	mdb->size++;
624 
625 out:
626 	return mp;
627 }
628 
629 struct net_bridge_port_group *br_multicast_new_port_group(
630 			struct net_bridge_port *port,
631 			struct br_ip *group,
632 			struct net_bridge_port_group __rcu *next,
633 			unsigned char state)
634 {
635 	struct net_bridge_port_group *p;
636 
637 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
638 	if (unlikely(!p))
639 		return NULL;
640 
641 	p->addr = *group;
642 	p->port = port;
643 	p->state = state;
644 	rcu_assign_pointer(p->next, next);
645 	hlist_add_head(&p->mglist, &port->mglist);
646 	setup_timer(&p->timer, br_multicast_port_group_expired,
647 		    (unsigned long)p);
648 	return p;
649 }
650 
651 static int br_multicast_add_group(struct net_bridge *br,
652 				  struct net_bridge_port *port,
653 				  struct br_ip *group)
654 {
655 	struct net_bridge_mdb_entry *mp;
656 	struct net_bridge_port_group *p;
657 	struct net_bridge_port_group __rcu **pp;
658 	unsigned long now = jiffies;
659 	int err;
660 
661 	spin_lock(&br->multicast_lock);
662 	if (!netif_running(br->dev) ||
663 	    (port && port->state == BR_STATE_DISABLED))
664 		goto out;
665 
666 	mp = br_multicast_new_group(br, port, group);
667 	err = PTR_ERR(mp);
668 	if (IS_ERR(mp))
669 		goto err;
670 
671 	if (!port) {
672 		mp->mglist = true;
673 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
674 		goto out;
675 	}
676 
677 	for (pp = &mp->ports;
678 	     (p = mlock_dereference(*pp, br)) != NULL;
679 	     pp = &p->next) {
680 		if (p->port == port)
681 			goto found;
682 		if ((unsigned long)p->port < (unsigned long)port)
683 			break;
684 	}
685 
686 	p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
687 	if (unlikely(!p))
688 		goto err;
689 	rcu_assign_pointer(*pp, p);
690 	br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
691 
692 found:
693 	mod_timer(&p->timer, now + br->multicast_membership_interval);
694 out:
695 	err = 0;
696 
697 err:
698 	spin_unlock(&br->multicast_lock);
699 	return err;
700 }
701 
702 static int br_ip4_multicast_add_group(struct net_bridge *br,
703 				      struct net_bridge_port *port,
704 				      __be32 group,
705 				      __u16 vid)
706 {
707 	struct br_ip br_group;
708 
709 	if (ipv4_is_local_multicast(group))
710 		return 0;
711 
712 	br_group.u.ip4 = group;
713 	br_group.proto = htons(ETH_P_IP);
714 	br_group.vid = vid;
715 
716 	return br_multicast_add_group(br, port, &br_group);
717 }
718 
719 #if IS_ENABLED(CONFIG_IPV6)
720 static int br_ip6_multicast_add_group(struct net_bridge *br,
721 				      struct net_bridge_port *port,
722 				      const struct in6_addr *group,
723 				      __u16 vid)
724 {
725 	struct br_ip br_group;
726 
727 	if (!ipv6_is_transient_multicast(group))
728 		return 0;
729 
730 	br_group.u.ip6 = *group;
731 	br_group.proto = htons(ETH_P_IPV6);
732 	br_group.vid = vid;
733 
734 	return br_multicast_add_group(br, port, &br_group);
735 }
736 #endif
737 
738 static void br_multicast_router_expired(unsigned long data)
739 {
740 	struct net_bridge_port *port = (void *)data;
741 	struct net_bridge *br = port->br;
742 
743 	spin_lock(&br->multicast_lock);
744 	if (port->multicast_router != 1 ||
745 	    timer_pending(&port->multicast_router_timer) ||
746 	    hlist_unhashed(&port->rlist))
747 		goto out;
748 
749 	hlist_del_init_rcu(&port->rlist);
750 
751 out:
752 	spin_unlock(&br->multicast_lock);
753 }
754 
755 static void br_multicast_local_router_expired(unsigned long data)
756 {
757 }
758 
759 static void br_multicast_querier_expired(unsigned long data)
760 {
761 	struct net_bridge *br = (void *)data;
762 
763 	spin_lock(&br->multicast_lock);
764 	if (!netif_running(br->dev) || br->multicast_disabled)
765 		goto out;
766 
767 	br_multicast_start_querier(br);
768 
769 out:
770 	spin_unlock(&br->multicast_lock);
771 }
772 
773 static void __br_multicast_send_query(struct net_bridge *br,
774 				      struct net_bridge_port *port,
775 				      struct br_ip *ip)
776 {
777 	struct sk_buff *skb;
778 
779 	skb = br_multicast_alloc_query(br, ip);
780 	if (!skb)
781 		return;
782 
783 	if (port) {
784 		__skb_push(skb, sizeof(struct ethhdr));
785 		skb->dev = port->dev;
786 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
787 			dev_queue_xmit);
788 	} else
789 		netif_rx(skb);
790 }
791 
792 static void br_multicast_send_query(struct net_bridge *br,
793 				    struct net_bridge_port *port, u32 sent)
794 {
795 	unsigned long time;
796 	struct br_ip br_group;
797 
798 	if (!netif_running(br->dev) || br->multicast_disabled ||
799 	    !br->multicast_querier ||
800 	    timer_pending(&br->multicast_querier_timer))
801 		return;
802 
803 	memset(&br_group.u, 0, sizeof(br_group.u));
804 
805 	br_group.proto = htons(ETH_P_IP);
806 	__br_multicast_send_query(br, port, &br_group);
807 
808 #if IS_ENABLED(CONFIG_IPV6)
809 	br_group.proto = htons(ETH_P_IPV6);
810 	__br_multicast_send_query(br, port, &br_group);
811 #endif
812 
813 	time = jiffies;
814 	time += sent < br->multicast_startup_query_count ?
815 		br->multicast_startup_query_interval :
816 		br->multicast_query_interval;
817 	mod_timer(port ? &port->multicast_query_timer :
818 			 &br->multicast_query_timer, time);
819 }
820 
821 static void br_multicast_port_query_expired(unsigned long data)
822 {
823 	struct net_bridge_port *port = (void *)data;
824 	struct net_bridge *br = port->br;
825 
826 	spin_lock(&br->multicast_lock);
827 	if (port->state == BR_STATE_DISABLED ||
828 	    port->state == BR_STATE_BLOCKING)
829 		goto out;
830 
831 	if (port->multicast_startup_queries_sent <
832 	    br->multicast_startup_query_count)
833 		port->multicast_startup_queries_sent++;
834 
835 	br_multicast_send_query(port->br, port,
836 				port->multicast_startup_queries_sent);
837 
838 out:
839 	spin_unlock(&br->multicast_lock);
840 }
841 
842 void br_multicast_add_port(struct net_bridge_port *port)
843 {
844 	port->multicast_router = 1;
845 
846 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
847 		    (unsigned long)port);
848 	setup_timer(&port->multicast_query_timer,
849 		    br_multicast_port_query_expired, (unsigned long)port);
850 }
851 
852 void br_multicast_del_port(struct net_bridge_port *port)
853 {
854 	del_timer_sync(&port->multicast_router_timer);
855 }
856 
857 static void __br_multicast_enable_port(struct net_bridge_port *port)
858 {
859 	port->multicast_startup_queries_sent = 0;
860 
861 	if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
862 	    del_timer(&port->multicast_query_timer))
863 		mod_timer(&port->multicast_query_timer, jiffies);
864 }
865 
866 void br_multicast_enable_port(struct net_bridge_port *port)
867 {
868 	struct net_bridge *br = port->br;
869 
870 	spin_lock(&br->multicast_lock);
871 	if (br->multicast_disabled || !netif_running(br->dev))
872 		goto out;
873 
874 	__br_multicast_enable_port(port);
875 
876 out:
877 	spin_unlock(&br->multicast_lock);
878 }
879 
880 void br_multicast_disable_port(struct net_bridge_port *port)
881 {
882 	struct net_bridge *br = port->br;
883 	struct net_bridge_port_group *pg;
884 	struct hlist_node *n;
885 
886 	spin_lock(&br->multicast_lock);
887 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
888 		br_multicast_del_pg(br, pg);
889 
890 	if (!hlist_unhashed(&port->rlist))
891 		hlist_del_init_rcu(&port->rlist);
892 	del_timer(&port->multicast_router_timer);
893 	del_timer(&port->multicast_query_timer);
894 	spin_unlock(&br->multicast_lock);
895 }
896 
897 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
898 					 struct net_bridge_port *port,
899 					 struct sk_buff *skb)
900 {
901 	struct igmpv3_report *ih;
902 	struct igmpv3_grec *grec;
903 	int i;
904 	int len;
905 	int num;
906 	int type;
907 	int err = 0;
908 	__be32 group;
909 	u16 vid = 0;
910 
911 	if (!pskb_may_pull(skb, sizeof(*ih)))
912 		return -EINVAL;
913 
914 	br_vlan_get_tag(skb, &vid);
915 	ih = igmpv3_report_hdr(skb);
916 	num = ntohs(ih->ngrec);
917 	len = sizeof(*ih);
918 
919 	for (i = 0; i < num; i++) {
920 		len += sizeof(*grec);
921 		if (!pskb_may_pull(skb, len))
922 			return -EINVAL;
923 
924 		grec = (void *)(skb->data + len - sizeof(*grec));
925 		group = grec->grec_mca;
926 		type = grec->grec_type;
927 
928 		len += ntohs(grec->grec_nsrcs) * 4;
929 		if (!pskb_may_pull(skb, len))
930 			return -EINVAL;
931 
932 		/* We treat this as an IGMPv2 report for now. */
933 		switch (type) {
934 		case IGMPV3_MODE_IS_INCLUDE:
935 		case IGMPV3_MODE_IS_EXCLUDE:
936 		case IGMPV3_CHANGE_TO_INCLUDE:
937 		case IGMPV3_CHANGE_TO_EXCLUDE:
938 		case IGMPV3_ALLOW_NEW_SOURCES:
939 		case IGMPV3_BLOCK_OLD_SOURCES:
940 			break;
941 
942 		default:
943 			continue;
944 		}
945 
946 		err = br_ip4_multicast_add_group(br, port, group, vid);
947 		if (err)
948 			break;
949 	}
950 
951 	return err;
952 }
953 
954 #if IS_ENABLED(CONFIG_IPV6)
955 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
956 					struct net_bridge_port *port,
957 					struct sk_buff *skb)
958 {
959 	struct icmp6hdr *icmp6h;
960 	struct mld2_grec *grec;
961 	int i;
962 	int len;
963 	int num;
964 	int err = 0;
965 	u16 vid = 0;
966 
967 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
968 		return -EINVAL;
969 
970 	br_vlan_get_tag(skb, &vid);
971 	icmp6h = icmp6_hdr(skb);
972 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
973 	len = sizeof(*icmp6h);
974 
975 	for (i = 0; i < num; i++) {
976 		__be16 *nsrcs, _nsrcs;
977 
978 		nsrcs = skb_header_pointer(skb,
979 					   len + offsetof(struct mld2_grec,
980 							  grec_nsrcs),
981 					   sizeof(_nsrcs), &_nsrcs);
982 		if (!nsrcs)
983 			return -EINVAL;
984 
985 		if (!pskb_may_pull(skb,
986 				   len + sizeof(*grec) +
987 				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
988 			return -EINVAL;
989 
990 		grec = (struct mld2_grec *)(skb->data + len);
991 		len += sizeof(*grec) +
992 		       sizeof(struct in6_addr) * ntohs(*nsrcs);
993 
994 		/* We treat these as MLDv1 reports for now. */
995 		switch (grec->grec_type) {
996 		case MLD2_MODE_IS_INCLUDE:
997 		case MLD2_MODE_IS_EXCLUDE:
998 		case MLD2_CHANGE_TO_INCLUDE:
999 		case MLD2_CHANGE_TO_EXCLUDE:
1000 		case MLD2_ALLOW_NEW_SOURCES:
1001 		case MLD2_BLOCK_OLD_SOURCES:
1002 			break;
1003 
1004 		default:
1005 			continue;
1006 		}
1007 
1008 		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1009 						 vid);
1010 		if (!err)
1011 			break;
1012 	}
1013 
1014 	return err;
1015 }
1016 #endif
1017 
1018 /*
1019  * Add port to rotuer_list
1020  *  list is maintained ordered by pointer value
1021  *  and locked by br->multicast_lock and RCU
1022  */
1023 static void br_multicast_add_router(struct net_bridge *br,
1024 				    struct net_bridge_port *port)
1025 {
1026 	struct net_bridge_port *p;
1027 	struct hlist_node *slot = NULL;
1028 
1029 	hlist_for_each_entry(p, &br->router_list, rlist) {
1030 		if ((unsigned long) port >= (unsigned long) p)
1031 			break;
1032 		slot = &p->rlist;
1033 	}
1034 
1035 	if (slot)
1036 		hlist_add_after_rcu(slot, &port->rlist);
1037 	else
1038 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1039 }
1040 
1041 static void br_multicast_mark_router(struct net_bridge *br,
1042 				     struct net_bridge_port *port)
1043 {
1044 	unsigned long now = jiffies;
1045 
1046 	if (!port) {
1047 		if (br->multicast_router == 1)
1048 			mod_timer(&br->multicast_router_timer,
1049 				  now + br->multicast_querier_interval);
1050 		return;
1051 	}
1052 
1053 	if (port->multicast_router != 1)
1054 		return;
1055 
1056 	if (!hlist_unhashed(&port->rlist))
1057 		goto timer;
1058 
1059 	br_multicast_add_router(br, port);
1060 
1061 timer:
1062 	mod_timer(&port->multicast_router_timer,
1063 		  now + br->multicast_querier_interval);
1064 }
1065 
1066 static void br_multicast_query_received(struct net_bridge *br,
1067 					struct net_bridge_port *port,
1068 					int saddr)
1069 {
1070 	if (saddr)
1071 		mod_timer(&br->multicast_querier_timer,
1072 			  jiffies + br->multicast_querier_interval);
1073 	else if (timer_pending(&br->multicast_querier_timer))
1074 		return;
1075 
1076 	br_multicast_mark_router(br, port);
1077 }
1078 
1079 static int br_ip4_multicast_query(struct net_bridge *br,
1080 				  struct net_bridge_port *port,
1081 				  struct sk_buff *skb)
1082 {
1083 	const struct iphdr *iph = ip_hdr(skb);
1084 	struct igmphdr *ih = igmp_hdr(skb);
1085 	struct net_bridge_mdb_entry *mp;
1086 	struct igmpv3_query *ih3;
1087 	struct net_bridge_port_group *p;
1088 	struct net_bridge_port_group __rcu **pp;
1089 	unsigned long max_delay;
1090 	unsigned long now = jiffies;
1091 	__be32 group;
1092 	int err = 0;
1093 	u16 vid = 0;
1094 
1095 	spin_lock(&br->multicast_lock);
1096 	if (!netif_running(br->dev) ||
1097 	    (port && port->state == BR_STATE_DISABLED))
1098 		goto out;
1099 
1100 	br_multicast_query_received(br, port, !!iph->saddr);
1101 
1102 	group = ih->group;
1103 
1104 	if (skb->len == sizeof(*ih)) {
1105 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1106 
1107 		if (!max_delay) {
1108 			max_delay = 10 * HZ;
1109 			group = 0;
1110 		}
1111 	} else {
1112 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1113 			err = -EINVAL;
1114 			goto out;
1115 		}
1116 
1117 		ih3 = igmpv3_query_hdr(skb);
1118 		if (ih3->nsrcs)
1119 			goto out;
1120 
1121 		max_delay = ih3->code ?
1122 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1123 	}
1124 
1125 	if (!group)
1126 		goto out;
1127 
1128 	br_vlan_get_tag(skb, &vid);
1129 	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1130 	if (!mp)
1131 		goto out;
1132 
1133 	max_delay *= br->multicast_last_member_count;
1134 
1135 	if (mp->mglist &&
1136 	    (timer_pending(&mp->timer) ?
1137 	     time_after(mp->timer.expires, now + max_delay) :
1138 	     try_to_del_timer_sync(&mp->timer) >= 0))
1139 		mod_timer(&mp->timer, now + max_delay);
1140 
1141 	for (pp = &mp->ports;
1142 	     (p = mlock_dereference(*pp, br)) != NULL;
1143 	     pp = &p->next) {
1144 		if (timer_pending(&p->timer) ?
1145 		    time_after(p->timer.expires, now + max_delay) :
1146 		    try_to_del_timer_sync(&p->timer) >= 0)
1147 			mod_timer(&p->timer, now + max_delay);
1148 	}
1149 
1150 out:
1151 	spin_unlock(&br->multicast_lock);
1152 	return err;
1153 }
1154 
1155 #if IS_ENABLED(CONFIG_IPV6)
1156 static int br_ip6_multicast_query(struct net_bridge *br,
1157 				  struct net_bridge_port *port,
1158 				  struct sk_buff *skb)
1159 {
1160 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1161 	struct mld_msg *mld;
1162 	struct net_bridge_mdb_entry *mp;
1163 	struct mld2_query *mld2q;
1164 	struct net_bridge_port_group *p;
1165 	struct net_bridge_port_group __rcu **pp;
1166 	unsigned long max_delay;
1167 	unsigned long now = jiffies;
1168 	const struct in6_addr *group = NULL;
1169 	int err = 0;
1170 	u16 vid = 0;
1171 
1172 	spin_lock(&br->multicast_lock);
1173 	if (!netif_running(br->dev) ||
1174 	    (port && port->state == BR_STATE_DISABLED))
1175 		goto out;
1176 
1177 	br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1178 
1179 	if (skb->len == sizeof(*mld)) {
1180 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1181 			err = -EINVAL;
1182 			goto out;
1183 		}
1184 		mld = (struct mld_msg *) icmp6_hdr(skb);
1185 		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1186 		if (max_delay)
1187 			group = &mld->mld_mca;
1188 	} else if (skb->len >= sizeof(*mld2q)) {
1189 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1190 			err = -EINVAL;
1191 			goto out;
1192 		}
1193 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1194 		if (!mld2q->mld2q_nsrcs)
1195 			group = &mld2q->mld2q_mca;
1196 		max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(ntohs(mld2q->mld2q_mrc)) : 1;
1197 	}
1198 
1199 	if (!group)
1200 		goto out;
1201 
1202 	br_vlan_get_tag(skb, &vid);
1203 	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1204 	if (!mp)
1205 		goto out;
1206 
1207 	max_delay *= br->multicast_last_member_count;
1208 	if (mp->mglist &&
1209 	    (timer_pending(&mp->timer) ?
1210 	     time_after(mp->timer.expires, now + max_delay) :
1211 	     try_to_del_timer_sync(&mp->timer) >= 0))
1212 		mod_timer(&mp->timer, now + max_delay);
1213 
1214 	for (pp = &mp->ports;
1215 	     (p = mlock_dereference(*pp, br)) != NULL;
1216 	     pp = &p->next) {
1217 		if (timer_pending(&p->timer) ?
1218 		    time_after(p->timer.expires, now + max_delay) :
1219 		    try_to_del_timer_sync(&p->timer) >= 0)
1220 			mod_timer(&p->timer, now + max_delay);
1221 	}
1222 
1223 out:
1224 	spin_unlock(&br->multicast_lock);
1225 	return err;
1226 }
1227 #endif
1228 
1229 static void br_multicast_leave_group(struct net_bridge *br,
1230 				     struct net_bridge_port *port,
1231 				     struct br_ip *group)
1232 {
1233 	struct net_bridge_mdb_htable *mdb;
1234 	struct net_bridge_mdb_entry *mp;
1235 	struct net_bridge_port_group *p;
1236 	unsigned long now;
1237 	unsigned long time;
1238 
1239 	spin_lock(&br->multicast_lock);
1240 	if (!netif_running(br->dev) ||
1241 	    (port && port->state == BR_STATE_DISABLED) ||
1242 	    timer_pending(&br->multicast_querier_timer))
1243 		goto out;
1244 
1245 	mdb = mlock_dereference(br->mdb, br);
1246 	mp = br_mdb_ip_get(mdb, group);
1247 	if (!mp)
1248 		goto out;
1249 
1250 	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1251 		struct net_bridge_port_group __rcu **pp;
1252 
1253 		for (pp = &mp->ports;
1254 		     (p = mlock_dereference(*pp, br)) != NULL;
1255 		     pp = &p->next) {
1256 			if (p->port != port)
1257 				continue;
1258 
1259 			rcu_assign_pointer(*pp, p->next);
1260 			hlist_del_init(&p->mglist);
1261 			del_timer(&p->timer);
1262 			call_rcu_bh(&p->rcu, br_multicast_free_pg);
1263 			br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1264 
1265 			if (!mp->ports && !mp->mglist &&
1266 			    netif_running(br->dev))
1267 				mod_timer(&mp->timer, jiffies);
1268 		}
1269 		goto out;
1270 	}
1271 
1272 	now = jiffies;
1273 	time = now + br->multicast_last_member_count *
1274 		     br->multicast_last_member_interval;
1275 
1276 	if (!port) {
1277 		if (mp->mglist &&
1278 		    (timer_pending(&mp->timer) ?
1279 		     time_after(mp->timer.expires, time) :
1280 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1281 			mod_timer(&mp->timer, time);
1282 		}
1283 
1284 		goto out;
1285 	}
1286 
1287 	for (p = mlock_dereference(mp->ports, br);
1288 	     p != NULL;
1289 	     p = mlock_dereference(p->next, br)) {
1290 		if (p->port != port)
1291 			continue;
1292 
1293 		if (!hlist_unhashed(&p->mglist) &&
1294 		    (timer_pending(&p->timer) ?
1295 		     time_after(p->timer.expires, time) :
1296 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1297 			mod_timer(&p->timer, time);
1298 		}
1299 
1300 		break;
1301 	}
1302 
1303 out:
1304 	spin_unlock(&br->multicast_lock);
1305 }
1306 
1307 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1308 					 struct net_bridge_port *port,
1309 					 __be32 group,
1310 					 __u16 vid)
1311 {
1312 	struct br_ip br_group;
1313 
1314 	if (ipv4_is_local_multicast(group))
1315 		return;
1316 
1317 	br_group.u.ip4 = group;
1318 	br_group.proto = htons(ETH_P_IP);
1319 	br_group.vid = vid;
1320 
1321 	br_multicast_leave_group(br, port, &br_group);
1322 }
1323 
1324 #if IS_ENABLED(CONFIG_IPV6)
1325 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1326 					 struct net_bridge_port *port,
1327 					 const struct in6_addr *group,
1328 					 __u16 vid)
1329 {
1330 	struct br_ip br_group;
1331 
1332 	if (!ipv6_is_transient_multicast(group))
1333 		return;
1334 
1335 	br_group.u.ip6 = *group;
1336 	br_group.proto = htons(ETH_P_IPV6);
1337 	br_group.vid = vid;
1338 
1339 	br_multicast_leave_group(br, port, &br_group);
1340 }
1341 #endif
1342 
1343 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1344 				 struct net_bridge_port *port,
1345 				 struct sk_buff *skb)
1346 {
1347 	struct sk_buff *skb2 = skb;
1348 	const struct iphdr *iph;
1349 	struct igmphdr *ih;
1350 	unsigned int len;
1351 	unsigned int offset;
1352 	int err;
1353 	u16 vid = 0;
1354 
1355 	/* We treat OOM as packet loss for now. */
1356 	if (!pskb_may_pull(skb, sizeof(*iph)))
1357 		return -EINVAL;
1358 
1359 	iph = ip_hdr(skb);
1360 
1361 	if (iph->ihl < 5 || iph->version != 4)
1362 		return -EINVAL;
1363 
1364 	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1365 		return -EINVAL;
1366 
1367 	iph = ip_hdr(skb);
1368 
1369 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1370 		return -EINVAL;
1371 
1372 	if (iph->protocol != IPPROTO_IGMP) {
1373 		if (!ipv4_is_local_multicast(iph->daddr))
1374 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1375 		return 0;
1376 	}
1377 
1378 	len = ntohs(iph->tot_len);
1379 	if (skb->len < len || len < ip_hdrlen(skb))
1380 		return -EINVAL;
1381 
1382 	if (skb->len > len) {
1383 		skb2 = skb_clone(skb, GFP_ATOMIC);
1384 		if (!skb2)
1385 			return -ENOMEM;
1386 
1387 		err = pskb_trim_rcsum(skb2, len);
1388 		if (err)
1389 			goto err_out;
1390 	}
1391 
1392 	len -= ip_hdrlen(skb2);
1393 	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1394 	__skb_pull(skb2, offset);
1395 	skb_reset_transport_header(skb2);
1396 
1397 	err = -EINVAL;
1398 	if (!pskb_may_pull(skb2, sizeof(*ih)))
1399 		goto out;
1400 
1401 	switch (skb2->ip_summed) {
1402 	case CHECKSUM_COMPLETE:
1403 		if (!csum_fold(skb2->csum))
1404 			break;
1405 		/* fall through */
1406 	case CHECKSUM_NONE:
1407 		skb2->csum = 0;
1408 		if (skb_checksum_complete(skb2))
1409 			goto out;
1410 	}
1411 
1412 	err = 0;
1413 
1414 	br_vlan_get_tag(skb2, &vid);
1415 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1416 	ih = igmp_hdr(skb2);
1417 
1418 	switch (ih->type) {
1419 	case IGMP_HOST_MEMBERSHIP_REPORT:
1420 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1421 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1422 		err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1423 		break;
1424 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1425 		err = br_ip4_multicast_igmp3_report(br, port, skb2);
1426 		break;
1427 	case IGMP_HOST_MEMBERSHIP_QUERY:
1428 		err = br_ip4_multicast_query(br, port, skb2);
1429 		break;
1430 	case IGMP_HOST_LEAVE_MESSAGE:
1431 		br_ip4_multicast_leave_group(br, port, ih->group, vid);
1432 		break;
1433 	}
1434 
1435 out:
1436 	__skb_push(skb2, offset);
1437 err_out:
1438 	if (skb2 != skb)
1439 		kfree_skb(skb2);
1440 	return err;
1441 }
1442 
1443 #if IS_ENABLED(CONFIG_IPV6)
1444 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1445 				 struct net_bridge_port *port,
1446 				 struct sk_buff *skb)
1447 {
1448 	struct sk_buff *skb2;
1449 	const struct ipv6hdr *ip6h;
1450 	u8 icmp6_type;
1451 	u8 nexthdr;
1452 	__be16 frag_off;
1453 	unsigned int len;
1454 	int offset;
1455 	int err;
1456 	u16 vid = 0;
1457 
1458 	if (!pskb_may_pull(skb, sizeof(*ip6h)))
1459 		return -EINVAL;
1460 
1461 	ip6h = ipv6_hdr(skb);
1462 
1463 	/*
1464 	 * We're interested in MLD messages only.
1465 	 *  - Version is 6
1466 	 *  - MLD has always Router Alert hop-by-hop option
1467 	 *  - But we do not support jumbrograms.
1468 	 */
1469 	if (ip6h->version != 6 ||
1470 	    ip6h->nexthdr != IPPROTO_HOPOPTS ||
1471 	    ip6h->payload_len == 0)
1472 		return 0;
1473 
1474 	len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1475 	if (skb->len < len)
1476 		return -EINVAL;
1477 
1478 	nexthdr = ip6h->nexthdr;
1479 	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1480 
1481 	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1482 		return 0;
1483 
1484 	/* Okay, we found ICMPv6 header */
1485 	skb2 = skb_clone(skb, GFP_ATOMIC);
1486 	if (!skb2)
1487 		return -ENOMEM;
1488 
1489 	err = -EINVAL;
1490 	if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1491 		goto out;
1492 
1493 	len -= offset - skb_network_offset(skb2);
1494 
1495 	__skb_pull(skb2, offset);
1496 	skb_reset_transport_header(skb2);
1497 	skb_postpull_rcsum(skb2, skb_network_header(skb2),
1498 			   skb_network_header_len(skb2));
1499 
1500 	icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1501 
1502 	switch (icmp6_type) {
1503 	case ICMPV6_MGM_QUERY:
1504 	case ICMPV6_MGM_REPORT:
1505 	case ICMPV6_MGM_REDUCTION:
1506 	case ICMPV6_MLD2_REPORT:
1507 		break;
1508 	default:
1509 		err = 0;
1510 		goto out;
1511 	}
1512 
1513 	/* Okay, we found MLD message. Check further. */
1514 	if (skb2->len > len) {
1515 		err = pskb_trim_rcsum(skb2, len);
1516 		if (err)
1517 			goto out;
1518 		err = -EINVAL;
1519 	}
1520 
1521 	ip6h = ipv6_hdr(skb2);
1522 
1523 	switch (skb2->ip_summed) {
1524 	case CHECKSUM_COMPLETE:
1525 		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1526 					IPPROTO_ICMPV6, skb2->csum))
1527 			break;
1528 		/*FALLTHROUGH*/
1529 	case CHECKSUM_NONE:
1530 		skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1531 							&ip6h->daddr,
1532 							skb2->len,
1533 							IPPROTO_ICMPV6, 0));
1534 		if (__skb_checksum_complete(skb2))
1535 			goto out;
1536 	}
1537 
1538 	err = 0;
1539 
1540 	br_vlan_get_tag(skb, &vid);
1541 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1542 
1543 	switch (icmp6_type) {
1544 	case ICMPV6_MGM_REPORT:
1545 	    {
1546 		struct mld_msg *mld;
1547 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1548 			err = -EINVAL;
1549 			goto out;
1550 		}
1551 		mld = (struct mld_msg *)skb_transport_header(skb2);
1552 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1553 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1554 		break;
1555 	    }
1556 	case ICMPV6_MLD2_REPORT:
1557 		err = br_ip6_multicast_mld2_report(br, port, skb2);
1558 		break;
1559 	case ICMPV6_MGM_QUERY:
1560 		err = br_ip6_multicast_query(br, port, skb2);
1561 		break;
1562 	case ICMPV6_MGM_REDUCTION:
1563 	    {
1564 		struct mld_msg *mld;
1565 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1566 			err = -EINVAL;
1567 			goto out;
1568 		}
1569 		mld = (struct mld_msg *)skb_transport_header(skb2);
1570 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1571 	    }
1572 	}
1573 
1574 out:
1575 	kfree_skb(skb2);
1576 	return err;
1577 }
1578 #endif
1579 
1580 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1581 		     struct sk_buff *skb)
1582 {
1583 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1584 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1585 
1586 	if (br->multicast_disabled)
1587 		return 0;
1588 
1589 	switch (skb->protocol) {
1590 	case htons(ETH_P_IP):
1591 		return br_multicast_ipv4_rcv(br, port, skb);
1592 #if IS_ENABLED(CONFIG_IPV6)
1593 	case htons(ETH_P_IPV6):
1594 		return br_multicast_ipv6_rcv(br, port, skb);
1595 #endif
1596 	}
1597 
1598 	return 0;
1599 }
1600 
1601 static void br_multicast_query_expired(unsigned long data)
1602 {
1603 	struct net_bridge *br = (void *)data;
1604 
1605 	spin_lock(&br->multicast_lock);
1606 	if (br->multicast_startup_queries_sent <
1607 	    br->multicast_startup_query_count)
1608 		br->multicast_startup_queries_sent++;
1609 
1610 	br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1611 
1612 	spin_unlock(&br->multicast_lock);
1613 }
1614 
1615 void br_multicast_init(struct net_bridge *br)
1616 {
1617 	br->hash_elasticity = 4;
1618 	br->hash_max = 512;
1619 
1620 	br->multicast_router = 1;
1621 	br->multicast_querier = 0;
1622 	br->multicast_last_member_count = 2;
1623 	br->multicast_startup_query_count = 2;
1624 
1625 	br->multicast_last_member_interval = HZ;
1626 	br->multicast_query_response_interval = 10 * HZ;
1627 	br->multicast_startup_query_interval = 125 * HZ / 4;
1628 	br->multicast_query_interval = 125 * HZ;
1629 	br->multicast_querier_interval = 255 * HZ;
1630 	br->multicast_membership_interval = 260 * HZ;
1631 
1632 	spin_lock_init(&br->multicast_lock);
1633 	setup_timer(&br->multicast_router_timer,
1634 		    br_multicast_local_router_expired, 0);
1635 	setup_timer(&br->multicast_querier_timer,
1636 		    br_multicast_querier_expired, (unsigned long)br);
1637 	setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1638 		    (unsigned long)br);
1639 }
1640 
1641 void br_multicast_open(struct net_bridge *br)
1642 {
1643 	br->multicast_startup_queries_sent = 0;
1644 
1645 	if (br->multicast_disabled)
1646 		return;
1647 
1648 	mod_timer(&br->multicast_query_timer, jiffies);
1649 }
1650 
1651 void br_multicast_stop(struct net_bridge *br)
1652 {
1653 	struct net_bridge_mdb_htable *mdb;
1654 	struct net_bridge_mdb_entry *mp;
1655 	struct hlist_node *n;
1656 	u32 ver;
1657 	int i;
1658 
1659 	del_timer_sync(&br->multicast_router_timer);
1660 	del_timer_sync(&br->multicast_querier_timer);
1661 	del_timer_sync(&br->multicast_query_timer);
1662 
1663 	spin_lock_bh(&br->multicast_lock);
1664 	mdb = mlock_dereference(br->mdb, br);
1665 	if (!mdb)
1666 		goto out;
1667 
1668 	br->mdb = NULL;
1669 
1670 	ver = mdb->ver;
1671 	for (i = 0; i < mdb->max; i++) {
1672 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1673 					  hlist[ver]) {
1674 			del_timer(&mp->timer);
1675 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1676 		}
1677 	}
1678 
1679 	if (mdb->old) {
1680 		spin_unlock_bh(&br->multicast_lock);
1681 		rcu_barrier_bh();
1682 		spin_lock_bh(&br->multicast_lock);
1683 		WARN_ON(mdb->old);
1684 	}
1685 
1686 	mdb->old = mdb;
1687 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1688 
1689 out:
1690 	spin_unlock_bh(&br->multicast_lock);
1691 }
1692 
1693 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1694 {
1695 	int err = -ENOENT;
1696 
1697 	spin_lock_bh(&br->multicast_lock);
1698 	if (!netif_running(br->dev))
1699 		goto unlock;
1700 
1701 	switch (val) {
1702 	case 0:
1703 	case 2:
1704 		del_timer(&br->multicast_router_timer);
1705 		/* fall through */
1706 	case 1:
1707 		br->multicast_router = val;
1708 		err = 0;
1709 		break;
1710 
1711 	default:
1712 		err = -EINVAL;
1713 		break;
1714 	}
1715 
1716 unlock:
1717 	spin_unlock_bh(&br->multicast_lock);
1718 
1719 	return err;
1720 }
1721 
1722 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1723 {
1724 	struct net_bridge *br = p->br;
1725 	int err = -ENOENT;
1726 
1727 	spin_lock(&br->multicast_lock);
1728 	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1729 		goto unlock;
1730 
1731 	switch (val) {
1732 	case 0:
1733 	case 1:
1734 	case 2:
1735 		p->multicast_router = val;
1736 		err = 0;
1737 
1738 		if (val < 2 && !hlist_unhashed(&p->rlist))
1739 			hlist_del_init_rcu(&p->rlist);
1740 
1741 		if (val == 1)
1742 			break;
1743 
1744 		del_timer(&p->multicast_router_timer);
1745 
1746 		if (val == 0)
1747 			break;
1748 
1749 		br_multicast_add_router(br, p);
1750 		break;
1751 
1752 	default:
1753 		err = -EINVAL;
1754 		break;
1755 	}
1756 
1757 unlock:
1758 	spin_unlock(&br->multicast_lock);
1759 
1760 	return err;
1761 }
1762 
1763 static void br_multicast_start_querier(struct net_bridge *br)
1764 {
1765 	struct net_bridge_port *port;
1766 
1767 	br_multicast_open(br);
1768 
1769 	list_for_each_entry(port, &br->port_list, list) {
1770 		if (port->state == BR_STATE_DISABLED ||
1771 		    port->state == BR_STATE_BLOCKING)
1772 			continue;
1773 
1774 		__br_multicast_enable_port(port);
1775 	}
1776 }
1777 
1778 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1779 {
1780 	int err = 0;
1781 	struct net_bridge_mdb_htable *mdb;
1782 
1783 	spin_lock_bh(&br->multicast_lock);
1784 	if (br->multicast_disabled == !val)
1785 		goto unlock;
1786 
1787 	br->multicast_disabled = !val;
1788 	if (br->multicast_disabled)
1789 		goto unlock;
1790 
1791 	if (!netif_running(br->dev))
1792 		goto unlock;
1793 
1794 	mdb = mlock_dereference(br->mdb, br);
1795 	if (mdb) {
1796 		if (mdb->old) {
1797 			err = -EEXIST;
1798 rollback:
1799 			br->multicast_disabled = !!val;
1800 			goto unlock;
1801 		}
1802 
1803 		err = br_mdb_rehash(&br->mdb, mdb->max,
1804 				    br->hash_elasticity);
1805 		if (err)
1806 			goto rollback;
1807 	}
1808 
1809 	br_multicast_start_querier(br);
1810 
1811 unlock:
1812 	spin_unlock_bh(&br->multicast_lock);
1813 
1814 	return err;
1815 }
1816 
1817 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1818 {
1819 	val = !!val;
1820 
1821 	spin_lock_bh(&br->multicast_lock);
1822 	if (br->multicast_querier == val)
1823 		goto unlock;
1824 
1825 	br->multicast_querier = val;
1826 	if (val)
1827 		br_multicast_start_querier(br);
1828 
1829 unlock:
1830 	spin_unlock_bh(&br->multicast_lock);
1831 
1832 	return 0;
1833 }
1834 
1835 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1836 {
1837 	int err = -ENOENT;
1838 	u32 old;
1839 	struct net_bridge_mdb_htable *mdb;
1840 
1841 	spin_lock(&br->multicast_lock);
1842 	if (!netif_running(br->dev))
1843 		goto unlock;
1844 
1845 	err = -EINVAL;
1846 	if (!is_power_of_2(val))
1847 		goto unlock;
1848 
1849 	mdb = mlock_dereference(br->mdb, br);
1850 	if (mdb && val < mdb->size)
1851 		goto unlock;
1852 
1853 	err = 0;
1854 
1855 	old = br->hash_max;
1856 	br->hash_max = val;
1857 
1858 	if (mdb) {
1859 		if (mdb->old) {
1860 			err = -EEXIST;
1861 rollback:
1862 			br->hash_max = old;
1863 			goto unlock;
1864 		}
1865 
1866 		err = br_mdb_rehash(&br->mdb, br->hash_max,
1867 				    br->hash_elasticity);
1868 		if (err)
1869 			goto rollback;
1870 	}
1871 
1872 unlock:
1873 	spin_unlock(&br->multicast_lock);
1874 
1875 	return err;
1876 }
1877