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32 results

br_multicast.c

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  • br_multicast.c 62.86 KiB
    /*
     * Bridge multicast support.
     *
     * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
     *
     * This program is free software; you can redistribute it and/or modify it
     * under the terms of the GNU General Public License as published by the Free
     * Software Foundation; either version 2 of the License, or (at your option)
     * any later version.
     *
     */
    
    #include <linux/err.h>
    #include <linux/export.h>
    #include <linux/if_ether.h>
    #include <linux/igmp.h>
    #include <linux/jhash.h>
    #include <linux/kernel.h>
    #include <linux/log2.h>
    #include <linux/netdevice.h>
    #include <linux/netfilter_bridge.h>
    #include <linux/random.h>
    #include <linux/rculist.h>
    #include <linux/skbuff.h>
    #include <linux/slab.h>
    #include <linux/timer.h>
    #include <linux/inetdevice.h>
    #include <linux/mroute.h>
    #include <net/ip.h>
    #include <net/switchdev.h>
    #if IS_ENABLED(CONFIG_IPV6)
    #include <net/ipv6.h>
    #include <net/mld.h>
    #include <net/ip6_checksum.h>
    #include <net/addrconf.h>
    #endif
    
    #include "br_private.h"
    
    static void br_multicast_start_querier(struct net_bridge *br,
    				       struct bridge_mcast_own_query *query);
    static void br_multicast_add_router(struct net_bridge *br,
    				    struct net_bridge_port *port);
    static void br_ip4_multicast_leave_group(struct net_bridge *br,
    					 struct net_bridge_port *port,
    					 __be32 group,
    					 __u16 vid,
    					 const unsigned char *src);
    
    static void __del_port_router(struct net_bridge_port *p);
    #if IS_ENABLED(CONFIG_IPV6)
    static void br_ip6_multicast_leave_group(struct net_bridge *br,
    					 struct net_bridge_port *port,
    					 const struct in6_addr *group,
    					 __u16 vid, const unsigned char *src);
    #endif
    unsigned int br_mdb_rehash_seq;
    
    static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
    {
    	if (a->proto != b->proto)
    		return 0;
    	if (a->vid != b->vid)
    		return 0;
    	switch (a->proto) {
    	case htons(ETH_P_IP):
    		return a->u.ip4 == b->u.ip4;
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
    #endif
    	}
    	return 0;
    }
    
    static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
    				__u16 vid)
    {
    	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
    				const struct in6_addr *ip,
    				__u16 vid)
    {
    	return jhash_2words(ipv6_addr_hash(ip), vid,
    			    mdb->secret) & (mdb->max - 1);
    }
    #endif
    
    static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
    			     struct br_ip *ip)
    {
    	switch (ip->proto) {
    	case htons(ETH_P_IP):
    		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
    #endif
    	}
    	return 0;
    }
    
    static struct net_bridge_mdb_entry *__br_mdb_ip_get(
    	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
    {
    	struct net_bridge_mdb_entry *mp;
    
    	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
    		if (br_ip_equal(&mp->addr, dst))
    			return mp;
    	}
    
    	return NULL;
    }
    
    struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
    					   struct br_ip *dst)
    {
    	if (!mdb)
    		return NULL;
    
    	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
    }
    
    static struct net_bridge_mdb_entry *br_mdb_ip4_get(
    	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
    {
    	struct br_ip br_dst;
    
    	br_dst.u.ip4 = dst;
    	br_dst.proto = htons(ETH_P_IP);
    	br_dst.vid = vid;
    
    	return br_mdb_ip_get(mdb, &br_dst);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static struct net_bridge_mdb_entry *br_mdb_ip6_get(
    	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
    	__u16 vid)
    {
    	struct br_ip br_dst;
    
    	br_dst.u.ip6 = *dst;
    	br_dst.proto = htons(ETH_P_IPV6);
    	br_dst.vid = vid;
    
    	return br_mdb_ip_get(mdb, &br_dst);
    }
    #endif
    
    struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
    					struct sk_buff *skb, u16 vid)
    {
    	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
    	struct br_ip ip;
    
    	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
    		return NULL;
    
    	if (BR_INPUT_SKB_CB(skb)->igmp)
    		return NULL;
    
    	ip.proto = skb->protocol;
    	ip.vid = vid;
    
    	switch (skb->protocol) {
    	case htons(ETH_P_IP):
    		ip.u.ip4 = ip_hdr(skb)->daddr;
    		break;
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		ip.u.ip6 = ipv6_hdr(skb)->daddr;
    		break;
    #endif
    	default:
    		return NULL;
    	}
    
    	return br_mdb_ip_get(mdb, &ip);
    }
    
    static void br_mdb_free(struct rcu_head *head)
    {
    	struct net_bridge_mdb_htable *mdb =
    		container_of(head, struct net_bridge_mdb_htable, rcu);
    	struct net_bridge_mdb_htable *old = mdb->old;
    
    	mdb->old = NULL;
    	kfree(old->mhash);
    	kfree(old);
    }
    
    static int br_mdb_copy(struct net_bridge_mdb_htable *new,
    		       struct net_bridge_mdb_htable *old,
    		       int elasticity)
    {
    	struct net_bridge_mdb_entry *mp;
    	int maxlen;
    	int len;
    	int i;
    
    	for (i = 0; i < old->max; i++)
    		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
    			hlist_add_head(&mp->hlist[new->ver],
    				       &new->mhash[br_ip_hash(new, &mp->addr)]);
    
    	if (!elasticity)
    		return 0;
    
    	maxlen = 0;
    	for (i = 0; i < new->max; i++) {
    		len = 0;
    		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
    			len++;
    		if (len > maxlen)
    			maxlen = len;
    	}
    
    	return maxlen > elasticity ? -EINVAL : 0;
    }
    
    void br_multicast_free_pg(struct rcu_head *head)
    {
    	struct net_bridge_port_group *p =
    		container_of(head, struct net_bridge_port_group, rcu);
    
    	kfree(p);
    }
    
    static void br_multicast_free_group(struct rcu_head *head)
    {
    	struct net_bridge_mdb_entry *mp =
    		container_of(head, struct net_bridge_mdb_entry, rcu);
    
    	kfree(mp);
    }
    
    static void br_multicast_group_expired(struct timer_list *t)
    {
    	struct net_bridge_mdb_entry *mp = from_timer(mp, t, timer);
    	struct net_bridge *br = mp->br;
    	struct net_bridge_mdb_htable *mdb;
    
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) || timer_pending(&mp->timer))
    		goto out;
    
    	mp->host_joined = false;
    	br_mdb_notify(br->dev, NULL, &mp->addr, RTM_DELMDB, 0);
    
    	if (mp->ports)
    		goto out;
    
    	mdb = mlock_dereference(br->mdb, br);
    
    	hlist_del_rcu(&mp->hlist[mdb->ver]);
    	mdb->size--;
    
    	call_rcu_bh(&mp->rcu, br_multicast_free_group);
    
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_multicast_del_pg(struct net_bridge *br,
    				struct net_bridge_port_group *pg)
    {
    	struct net_bridge_mdb_htable *mdb;
    	struct net_bridge_mdb_entry *mp;
    	struct net_bridge_port_group *p;
    	struct net_bridge_port_group __rcu **pp;
    
    	mdb = mlock_dereference(br->mdb, br);
    
    	mp = br_mdb_ip_get(mdb, &pg->addr);
    	if (WARN_ON(!mp))
    		return;
    
    	for (pp = &mp->ports;
    	     (p = mlock_dereference(*pp, br)) != NULL;
    	     pp = &p->next) {
    		if (p != pg)
    			continue;
    
    		rcu_assign_pointer(*pp, p->next);
    		hlist_del_init(&p->mglist);
    		del_timer(&p->timer);
    		br_mdb_notify(br->dev, p->port, &pg->addr, RTM_DELMDB,
    			      p->flags);
    		call_rcu_bh(&p->rcu, br_multicast_free_pg);
    
    		if (!mp->ports && !mp->host_joined &&
    		    netif_running(br->dev))
    			mod_timer(&mp->timer, jiffies);
    
    		return;
    	}
    
    	WARN_ON(1);
    }
    
    static void br_multicast_port_group_expired(struct timer_list *t)
    {
    	struct net_bridge_port_group *pg = from_timer(pg, t, timer);
    	struct net_bridge *br = pg->port->br;
    
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
    	    hlist_unhashed(&pg->mglist) || pg->flags & MDB_PG_FLAGS_PERMANENT)
    		goto out;
    
    	br_multicast_del_pg(br, pg);
    
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
    			 int elasticity)
    {
    	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
    	struct net_bridge_mdb_htable *mdb;
    	int err;
    
    	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
    	if (!mdb)
    		return -ENOMEM;
    
    	mdb->max = max;
    	mdb->old = old;
    
    	mdb->mhash = kcalloc(max, sizeof(*mdb->mhash), GFP_ATOMIC);
    	if (!mdb->mhash) {
    		kfree(mdb);
    		return -ENOMEM;
    	}
    
    	mdb->size = old ? old->size : 0;
    	mdb->ver = old ? old->ver ^ 1 : 0;
    
    	if (!old || elasticity)
    		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
    	else
    		mdb->secret = old->secret;
    
    	if (!old)
    		goto out;
    
    	err = br_mdb_copy(mdb, old, elasticity);
    	if (err) {
    		kfree(mdb->mhash);
    		kfree(mdb);
    		return err;
    	}
    
    	br_mdb_rehash_seq++;
    	call_rcu_bh(&mdb->rcu, br_mdb_free);
    
    out:
    	rcu_assign_pointer(*mdbp, mdb);
    
    	return 0;
    }
    
    static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
    						    __be32 group,
    						    u8 *igmp_type)
    {
    	struct igmpv3_query *ihv3;
    	size_t igmp_hdr_size;
    	struct sk_buff *skb;
    	struct igmphdr *ih;
    	struct ethhdr *eth;
    	struct iphdr *iph;
    
    	igmp_hdr_size = sizeof(*ih);
    	if (br->multicast_igmp_version == 3)
    		igmp_hdr_size = sizeof(*ihv3);
    	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
    						 igmp_hdr_size + 4);
    	if (!skb)
    		goto out;
    
    	skb->protocol = htons(ETH_P_IP);
    
    	skb_reset_mac_header(skb);
    	eth = eth_hdr(skb);
    
    	ether_addr_copy(eth->h_source, br->dev->dev_addr);
    	eth->h_dest[0] = 1;
    	eth->h_dest[1] = 0;
    	eth->h_dest[2] = 0x5e;
    	eth->h_dest[3] = 0;
    	eth->h_dest[4] = 0;
    	eth->h_dest[5] = 1;
    	eth->h_proto = htons(ETH_P_IP);
    	skb_put(skb, sizeof(*eth));
    
    	skb_set_network_header(skb, skb->len);
    	iph = ip_hdr(skb);
    
    	iph->version = 4;
    	iph->ihl = 6;
    	iph->tos = 0xc0;
    	iph->tot_len = htons(sizeof(*iph) + igmp_hdr_size + 4);
    	iph->id = 0;
    	iph->frag_off = htons(IP_DF);
    	iph->ttl = 1;
    	iph->protocol = IPPROTO_IGMP;
    	iph->saddr = br_opt_get(br, BROPT_MULTICAST_QUERY_USE_IFADDR) ?
    		     inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
    	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
    	((u8 *)&iph[1])[0] = IPOPT_RA;
    	((u8 *)&iph[1])[1] = 4;
    	((u8 *)&iph[1])[2] = 0;
    	((u8 *)&iph[1])[3] = 0;
    	ip_send_check(iph);
    	skb_put(skb, 24);
    
    	skb_set_transport_header(skb, skb->len);
    	*igmp_type = IGMP_HOST_MEMBERSHIP_QUERY;
    
    	switch (br->multicast_igmp_version) {
    	case 2:
    		ih = igmp_hdr(skb);
    		ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
    		ih->code = (group ? br->multicast_last_member_interval :
    				    br->multicast_query_response_interval) /
    			   (HZ / IGMP_TIMER_SCALE);
    		ih->group = group;
    		ih->csum = 0;
    		ih->csum = ip_compute_csum((void *)ih, sizeof(*ih));
    		break;
    	case 3:
    		ihv3 = igmpv3_query_hdr(skb);
    		ihv3->type = IGMP_HOST_MEMBERSHIP_QUERY;
    		ihv3->code = (group ? br->multicast_last_member_interval :
    				      br->multicast_query_response_interval) /
    			     (HZ / IGMP_TIMER_SCALE);
    		ihv3->group = group;
    		ihv3->qqic = br->multicast_query_interval / HZ;
    		ihv3->nsrcs = 0;
    		ihv3->resv = 0;
    		ihv3->suppress = 0;
    		ihv3->qrv = 2;
    		ihv3->csum = 0;
    		ihv3->csum = ip_compute_csum((void *)ihv3, sizeof(*ihv3));
    		break;
    	}
    
    	skb_put(skb, igmp_hdr_size);
    	__skb_pull(skb, sizeof(*eth));
    
    out:
    	return skb;
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
    						    const struct in6_addr *grp,
    						    u8 *igmp_type)
    {
    	struct mld2_query *mld2q;
    	unsigned long interval;
    	struct ipv6hdr *ip6h;
    	struct mld_msg *mldq;
    	size_t mld_hdr_size;
    	struct sk_buff *skb;
    	struct ethhdr *eth;
    	u8 *hopopt;
    
    	mld_hdr_size = sizeof(*mldq);
    	if (br->multicast_mld_version == 2)
    		mld_hdr_size = sizeof(*mld2q);
    	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
    						 8 + mld_hdr_size);
    	if (!skb)
    		goto out;
    
    	skb->protocol = htons(ETH_P_IPV6);
    
    	/* Ethernet header */
    	skb_reset_mac_header(skb);
    	eth = eth_hdr(skb);
    
    	ether_addr_copy(eth->h_source, br->dev->dev_addr);
    	eth->h_proto = htons(ETH_P_IPV6);
    	skb_put(skb, sizeof(*eth));
    
    	/* IPv6 header + HbH option */
    	skb_set_network_header(skb, skb->len);
    	ip6h = ipv6_hdr(skb);
    
    	*(__force __be32 *)ip6h = htonl(0x60000000);
    	ip6h->payload_len = htons(8 + mld_hdr_size);
    	ip6h->nexthdr = IPPROTO_HOPOPTS;
    	ip6h->hop_limit = 1;
    	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
    	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
    			       &ip6h->saddr)) {
    		kfree_skb(skb);
    		br_opt_toggle(br, BROPT_HAS_IPV6_ADDR, false);
    		return NULL;
    	}
    
    	br_opt_toggle(br, BROPT_HAS_IPV6_ADDR, true);
    	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
    
    	hopopt = (u8 *)(ip6h + 1);
    	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
    	hopopt[1] = 0;				/* length of HbH */
    	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
    	hopopt[3] = 2;				/* Length of RA Option */
    	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
    	hopopt[5] = 0;
    	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
    	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
    
    	skb_put(skb, sizeof(*ip6h) + 8);
    
    	/* ICMPv6 */
    	skb_set_transport_header(skb, skb->len);
    	interval = ipv6_addr_any(grp) ?
    			br->multicast_query_response_interval :
    			br->multicast_last_member_interval;
    	*igmp_type = ICMPV6_MGM_QUERY;
    	switch (br->multicast_mld_version) {
    	case 1:
    		mldq = (struct mld_msg *)icmp6_hdr(skb);
    		mldq->mld_type = ICMPV6_MGM_QUERY;
    		mldq->mld_code = 0;
    		mldq->mld_cksum = 0;
    		mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
    		mldq->mld_reserved = 0;
    		mldq->mld_mca = *grp;
    		mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
    						  sizeof(*mldq), IPPROTO_ICMPV6,
    						  csum_partial(mldq,
    							       sizeof(*mldq),
    							       0));
    		break;
    	case 2:
    		mld2q = (struct mld2_query *)icmp6_hdr(skb);
    		mld2q->mld2q_mrc = htons((u16)jiffies_to_msecs(interval));
    		mld2q->mld2q_type = ICMPV6_MGM_QUERY;
    		mld2q->mld2q_code = 0;
    		mld2q->mld2q_cksum = 0;
    		mld2q->mld2q_resv1 = 0;
    		mld2q->mld2q_resv2 = 0;
    		mld2q->mld2q_suppress = 0;
    		mld2q->mld2q_qrv = 2;
    		mld2q->mld2q_nsrcs = 0;
    		mld2q->mld2q_qqic = br->multicast_query_interval / HZ;
    		mld2q->mld2q_mca = *grp;
    		mld2q->mld2q_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
    						     sizeof(*mld2q),
    						     IPPROTO_ICMPV6,
    						     csum_partial(mld2q,
    								  sizeof(*mld2q),
    								  0));
    		break;
    	}
    	skb_put(skb, mld_hdr_size);
    
    	__skb_pull(skb, sizeof(*eth));
    
    out:
    	return skb;
    }
    #endif
    
    static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
    						struct br_ip *addr,
    						u8 *igmp_type)
    {
    	switch (addr->proto) {
    	case htons(ETH_P_IP):
    		return br_ip4_multicast_alloc_query(br, addr->u.ip4, igmp_type);
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		return br_ip6_multicast_alloc_query(br, &addr->u.ip6,
    						    igmp_type);
    #endif
    	}
    	return NULL;
    }
    
    static struct net_bridge_mdb_entry *br_multicast_get_group(
    	struct net_bridge *br, struct net_bridge_port *port,
    	struct br_ip *group, int hash)
    {
    	struct net_bridge_mdb_htable *mdb;
    	struct net_bridge_mdb_entry *mp;
    	unsigned int count = 0;
    	unsigned int max;
    	int elasticity;
    	int err;
    
    	mdb = rcu_dereference_protected(br->mdb, 1);
    	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
    		count++;
    		if (unlikely(br_ip_equal(group, &mp->addr)))
    			return mp;
    	}
    
    	elasticity = 0;
    	max = mdb->max;
    
    	if (unlikely(count > br->hash_elasticity && count)) {
    		if (net_ratelimit())
    			br_info(br, "Multicast hash table "
    				"chain limit reached: %s\n",
    				port ? port->dev->name : br->dev->name);
    
    		elasticity = br->hash_elasticity;
    	}
    
    	if (mdb->size >= max) {
    		max *= 2;
    		if (unlikely(max > br->hash_max)) {
    			br_warn(br, "Multicast hash table maximum of %d "
    				"reached, disabling snooping: %s\n",
    				br->hash_max,
    				port ? port->dev->name : br->dev->name);
    			err = -E2BIG;
    disable:
    			br_opt_toggle(br, BROPT_MULTICAST_ENABLED, false);
    			goto err;
    		}
    	}
    
    	if (max > mdb->max || elasticity) {
    		if (mdb->old) {
    			if (net_ratelimit())
    				br_info(br, "Multicast hash table "
    					"on fire: %s\n",
    					port ? port->dev->name : br->dev->name);
    			err = -EEXIST;
    			goto err;
    		}
    
    		err = br_mdb_rehash(&br->mdb, max, elasticity);
    		if (err) {
    			br_warn(br, "Cannot rehash multicast "
    				"hash table, disabling snooping: %s, %d, %d\n",
    				port ? port->dev->name : br->dev->name,
    				mdb->size, err);
    			goto disable;
    		}
    
    		err = -EAGAIN;
    		goto err;
    	}
    
    	return NULL;
    
    err:
    	mp = ERR_PTR(err);
    	return mp;
    }
    
    struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
    						    struct net_bridge_port *p,
    						    struct br_ip *group)
    {
    	struct net_bridge_mdb_htable *mdb;
    	struct net_bridge_mdb_entry *mp;
    	int hash;
    	int err;
    
    	mdb = rcu_dereference_protected(br->mdb, 1);
    	if (!mdb) {
    		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
    		if (err)
    			return ERR_PTR(err);
    		goto rehash;
    	}
    
    	hash = br_ip_hash(mdb, group);
    	mp = br_multicast_get_group(br, p, group, hash);
    	switch (PTR_ERR(mp)) {
    	case 0:
    		break;
    
    	case -EAGAIN:
    rehash:
    		mdb = rcu_dereference_protected(br->mdb, 1);
    		hash = br_ip_hash(mdb, group);
    		break;
    
    	default:
    		goto out;
    	}
    
    	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
    	if (unlikely(!mp))
    		return ERR_PTR(-ENOMEM);
    
    	mp->br = br;
    	mp->addr = *group;
    	timer_setup(&mp->timer, br_multicast_group_expired, 0);
    
    	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
    	mdb->size++;
    
    out:
    	return mp;
    }
    
    struct net_bridge_port_group *br_multicast_new_port_group(
    			struct net_bridge_port *port,
    			struct br_ip *group,
    			struct net_bridge_port_group __rcu *next,
    			unsigned char flags,
    			const unsigned char *src)
    {
    	struct net_bridge_port_group *p;
    
    	p = kzalloc(sizeof(*p), GFP_ATOMIC);
    	if (unlikely(!p))
    		return NULL;
    
    	p->addr = *group;
    	p->port = port;
    	p->flags = flags;
    	rcu_assign_pointer(p->next, next);
    	hlist_add_head(&p->mglist, &port->mglist);
    	timer_setup(&p->timer, br_multicast_port_group_expired, 0);
    
    	if (src)
    		memcpy(p->eth_addr, src, ETH_ALEN);
    	else
    		memset(p->eth_addr, 0xff, ETH_ALEN);
    
    	return p;
    }
    
    static bool br_port_group_equal(struct net_bridge_port_group *p,
    				struct net_bridge_port *port,
    				const unsigned char *src)
    {
    	if (p->port != port)
    		return false;
    
    	if (!(port->flags & BR_MULTICAST_TO_UNICAST))
    		return true;
    
    	return ether_addr_equal(src, p->eth_addr);
    }
    
    static int br_multicast_add_group(struct net_bridge *br,
    				  struct net_bridge_port *port,
    				  struct br_ip *group,
    				  const unsigned char *src)
    {
    	struct net_bridge_port_group __rcu **pp;
    	struct net_bridge_port_group *p;
    	struct net_bridge_mdb_entry *mp;
    	unsigned long now = jiffies;
    	int err;
    
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) ||
    	    (port && port->state == BR_STATE_DISABLED))
    		goto out;
    
    	mp = br_multicast_new_group(br, port, group);
    	err = PTR_ERR(mp);
    	if (IS_ERR(mp))
    		goto err;
    
    	if (!port) {
    		if (!mp->host_joined) {
    			mp->host_joined = true;
    			br_mdb_notify(br->dev, NULL, &mp->addr, RTM_NEWMDB, 0);
    		}
    		mod_timer(&mp->timer, now + br->multicast_membership_interval);
    		goto out;
    	}
    
    	for (pp = &mp->ports;
    	     (p = mlock_dereference(*pp, br)) != NULL;
    	     pp = &p->next) {
    		if (br_port_group_equal(p, port, src))
    			goto found;
    		if ((unsigned long)p->port < (unsigned long)port)
    			break;
    	}
    
    	p = br_multicast_new_port_group(port, group, *pp, 0, src);
    	if (unlikely(!p))
    		goto err;
    	rcu_assign_pointer(*pp, p);
    	br_mdb_notify(br->dev, port, group, RTM_NEWMDB, 0);
    
    found:
    	mod_timer(&p->timer, now + br->multicast_membership_interval);
    out:
    	err = 0;
    
    err:
    	spin_unlock(&br->multicast_lock);
    	return err;
    }
    
    static int br_ip4_multicast_add_group(struct net_bridge *br,
    				      struct net_bridge_port *port,
    				      __be32 group,
    				      __u16 vid,
    				      const unsigned char *src)
    {
    	struct br_ip br_group;
    
    	if (ipv4_is_local_multicast(group))
    		return 0;
    
    	br_group.u.ip4 = group;
    	br_group.proto = htons(ETH_P_IP);
    	br_group.vid = vid;
    
    	return br_multicast_add_group(br, port, &br_group, src);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static int br_ip6_multicast_add_group(struct net_bridge *br,
    				      struct net_bridge_port *port,
    				      const struct in6_addr *group,
    				      __u16 vid,
    				      const unsigned char *src)
    {
    	struct br_ip br_group;
    
    	if (ipv6_addr_is_ll_all_nodes(group))
    		return 0;
    
    	br_group.u.ip6 = *group;
    	br_group.proto = htons(ETH_P_IPV6);
    	br_group.vid = vid;
    
    	return br_multicast_add_group(br, port, &br_group, src);
    }
    #endif
    
    static void br_multicast_router_expired(struct timer_list *t)
    {
    	struct net_bridge_port *port =
    			from_timer(port, t, multicast_router_timer);
    	struct net_bridge *br = port->br;
    
    	spin_lock(&br->multicast_lock);
    	if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
    	    port->multicast_router == MDB_RTR_TYPE_PERM ||
    	    timer_pending(&port->multicast_router_timer))
    		goto out;
    
    	__del_port_router(port);
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_mc_router_state_change(struct net_bridge *p,
    				      bool is_mc_router)
    {
    	struct switchdev_attr attr = {
    		.orig_dev = p->dev,
    		.id = SWITCHDEV_ATTR_ID_BRIDGE_MROUTER,
    		.flags = SWITCHDEV_F_DEFER,
    		.u.mrouter = is_mc_router,
    	};
    
    	switchdev_port_attr_set(p->dev, &attr);
    }
    
    static void br_multicast_local_router_expired(struct timer_list *t)
    {
    	struct net_bridge *br = from_timer(br, t, multicast_router_timer);
    
    	spin_lock(&br->multicast_lock);
    	if (br->multicast_router == MDB_RTR_TYPE_DISABLED ||
    	    br->multicast_router == MDB_RTR_TYPE_PERM ||
    	    timer_pending(&br->multicast_router_timer))
    		goto out;
    
    	br_mc_router_state_change(br, false);
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_multicast_querier_expired(struct net_bridge *br,
    					 struct bridge_mcast_own_query *query)
    {
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) || !br_opt_get(br, BROPT_MULTICAST_ENABLED))
    		goto out;
    
    	br_multicast_start_querier(br, query);
    
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_ip4_multicast_querier_expired(struct timer_list *t)
    {
    	struct net_bridge *br = from_timer(br, t, ip4_other_query.timer);
    
    	br_multicast_querier_expired(br, &br->ip4_own_query);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static void br_ip6_multicast_querier_expired(struct timer_list *t)
    {
    	struct net_bridge *br = from_timer(br, t, ip6_other_query.timer);
    
    	br_multicast_querier_expired(br, &br->ip6_own_query);
    }
    #endif
    
    static void br_multicast_select_own_querier(struct net_bridge *br,
    					    struct br_ip *ip,
    					    struct sk_buff *skb)
    {
    	if (ip->proto == htons(ETH_P_IP))
    		br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
    #if IS_ENABLED(CONFIG_IPV6)
    	else
    		br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
    #endif
    }
    
    static void __br_multicast_send_query(struct net_bridge *br,
    				      struct net_bridge_port *port,
    				      struct br_ip *ip)
    {
    	struct sk_buff *skb;
    	u8 igmp_type;
    
    	skb = br_multicast_alloc_query(br, ip, &igmp_type);
    	if (!skb)
    		return;
    
    	if (port) {
    		skb->dev = port->dev;
    		br_multicast_count(br, port, skb, igmp_type,
    				   BR_MCAST_DIR_TX);
    		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
    			dev_net(port->dev), NULL, skb, NULL, skb->dev,
    			br_dev_queue_push_xmit);
    	} else {
    		br_multicast_select_own_querier(br, ip, skb);
    		br_multicast_count(br, port, skb, igmp_type,
    				   BR_MCAST_DIR_RX);
    		netif_rx(skb);
    	}
    }
    
    static void br_multicast_send_query(struct net_bridge *br,
    				    struct net_bridge_port *port,
    				    struct bridge_mcast_own_query *own_query)
    {
    	struct bridge_mcast_other_query *other_query = NULL;
    	struct br_ip br_group;
    	unsigned long time;
    
    	if (!netif_running(br->dev) ||
    	    !br_opt_get(br, BROPT_MULTICAST_ENABLED) ||
    	    !br_opt_get(br, BROPT_MULTICAST_QUERIER))
    		return;
    
    	memset(&br_group.u, 0, sizeof(br_group.u));
    
    	if (port ? (own_query == &port->ip4_own_query) :
    		   (own_query == &br->ip4_own_query)) {
    		other_query = &br->ip4_other_query;
    		br_group.proto = htons(ETH_P_IP);
    #if IS_ENABLED(CONFIG_IPV6)
    	} else {
    		other_query = &br->ip6_other_query;
    		br_group.proto = htons(ETH_P_IPV6);
    #endif
    	}
    
    	if (!other_query || timer_pending(&other_query->timer))
    		return;
    
    	__br_multicast_send_query(br, port, &br_group);
    
    	time = jiffies;
    	time += own_query->startup_sent < br->multicast_startup_query_count ?
    		br->multicast_startup_query_interval :
    		br->multicast_query_interval;
    	mod_timer(&own_query->timer, time);
    }
    
    static void
    br_multicast_port_query_expired(struct net_bridge_port *port,
    				struct bridge_mcast_own_query *query)
    {
    	struct net_bridge *br = port->br;
    
    	spin_lock(&br->multicast_lock);
    	if (port->state == BR_STATE_DISABLED ||
    	    port->state == BR_STATE_BLOCKING)
    		goto out;
    
    	if (query->startup_sent < br->multicast_startup_query_count)
    		query->startup_sent++;
    
    	br_multicast_send_query(port->br, port, query);
    
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_ip4_multicast_port_query_expired(struct timer_list *t)
    {
    	struct net_bridge_port *port = from_timer(port, t, ip4_own_query.timer);
    
    	br_multicast_port_query_expired(port, &port->ip4_own_query);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static void br_ip6_multicast_port_query_expired(struct timer_list *t)
    {
    	struct net_bridge_port *port = from_timer(port, t, ip6_own_query.timer);
    
    	br_multicast_port_query_expired(port, &port->ip6_own_query);
    }
    #endif
    
    static void br_mc_disabled_update(struct net_device *dev, bool value)
    {
    	struct switchdev_attr attr = {
    		.orig_dev = dev,
    		.id = SWITCHDEV_ATTR_ID_BRIDGE_MC_DISABLED,
    		.flags = SWITCHDEV_F_DEFER,
    		.u.mc_disabled = !value,
    	};
    
    	switchdev_port_attr_set(dev, &attr);
    }
    
    int br_multicast_add_port(struct net_bridge_port *port)
    {
    	port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
    
    	timer_setup(&port->multicast_router_timer,
    		    br_multicast_router_expired, 0);
    	timer_setup(&port->ip4_own_query.timer,
    		    br_ip4_multicast_port_query_expired, 0);
    #if IS_ENABLED(CONFIG_IPV6)
    	timer_setup(&port->ip6_own_query.timer,
    		    br_ip6_multicast_port_query_expired, 0);
    #endif
    	br_mc_disabled_update(port->dev,
    			      br_opt_get(port->br, BROPT_MULTICAST_ENABLED));
    
    	port->mcast_stats = netdev_alloc_pcpu_stats(struct bridge_mcast_stats);
    	if (!port->mcast_stats)
    		return -ENOMEM;
    
    	return 0;
    }
    
    void br_multicast_del_port(struct net_bridge_port *port)
    {
    	struct net_bridge *br = port->br;
    	struct net_bridge_port_group *pg;
    	struct hlist_node *n;
    
    	/* Take care of the remaining groups, only perm ones should be left */
    	spin_lock_bh(&br->multicast_lock);
    	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
    		br_multicast_del_pg(br, pg);
    	spin_unlock_bh(&br->multicast_lock);
    	del_timer_sync(&port->multicast_router_timer);
    	free_percpu(port->mcast_stats);
    }
    
    static void br_multicast_enable(struct bridge_mcast_own_query *query)
    {
    	query->startup_sent = 0;
    
    	if (try_to_del_timer_sync(&query->timer) >= 0 ||
    	    del_timer(&query->timer))
    		mod_timer(&query->timer, jiffies);
    }
    
    static void __br_multicast_enable_port(struct net_bridge_port *port)
    {
    	struct net_bridge *br = port->br;
    
    	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED) || !netif_running(br->dev))
    		return;
    
    	br_multicast_enable(&port->ip4_own_query);
    #if IS_ENABLED(CONFIG_IPV6)
    	br_multicast_enable(&port->ip6_own_query);
    #endif
    	if (port->multicast_router == MDB_RTR_TYPE_PERM &&
    	    hlist_unhashed(&port->rlist))
    		br_multicast_add_router(br, port);
    }
    
    void br_multicast_enable_port(struct net_bridge_port *port)
    {
    	struct net_bridge *br = port->br;
    
    	spin_lock(&br->multicast_lock);
    	__br_multicast_enable_port(port);
    	spin_unlock(&br->multicast_lock);
    }
    
    void br_multicast_disable_port(struct net_bridge_port *port)
    {
    	struct net_bridge *br = port->br;
    	struct net_bridge_port_group *pg;
    	struct hlist_node *n;
    
    	spin_lock(&br->multicast_lock);
    	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
    		if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
    			br_multicast_del_pg(br, pg);
    
    	__del_port_router(port);
    
    	del_timer(&port->multicast_router_timer);
    	del_timer(&port->ip4_own_query.timer);
    #if IS_ENABLED(CONFIG_IPV6)
    	del_timer(&port->ip6_own_query.timer);
    #endif
    	spin_unlock(&br->multicast_lock);
    }
    
    static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
    					 struct net_bridge_port *port,
    					 struct sk_buff *skb,
    					 u16 vid)
    {
    	const unsigned char *src;
    	struct igmpv3_report *ih;
    	struct igmpv3_grec *grec;
    	int i;
    	int len;
    	int num;
    	int type;
    	int err = 0;
    	__be32 group;
    
    	ih = igmpv3_report_hdr(skb);
    	num = ntohs(ih->ngrec);
    	len = skb_transport_offset(skb) + sizeof(*ih);
    
    	for (i = 0; i < num; i++) {
    		len += sizeof(*grec);
    		if (!pskb_may_pull(skb, len))
    			return -EINVAL;
    
    		grec = (void *)(skb->data + len - sizeof(*grec));
    		group = grec->grec_mca;
    		type = grec->grec_type;
    
    		len += ntohs(grec->grec_nsrcs) * 4;
    		if (!pskb_may_pull(skb, len))
    			return -EINVAL;
    
    		/* We treat this as an IGMPv2 report for now. */
    		switch (type) {
    		case IGMPV3_MODE_IS_INCLUDE:
    		case IGMPV3_MODE_IS_EXCLUDE:
    		case IGMPV3_CHANGE_TO_INCLUDE:
    		case IGMPV3_CHANGE_TO_EXCLUDE:
    		case IGMPV3_ALLOW_NEW_SOURCES:
    		case IGMPV3_BLOCK_OLD_SOURCES:
    			break;
    
    		default:
    			continue;
    		}
    
    		src = eth_hdr(skb)->h_source;
    		if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
    		     type == IGMPV3_MODE_IS_INCLUDE) &&
    		    ntohs(grec->grec_nsrcs) == 0) {
    			br_ip4_multicast_leave_group(br, port, group, vid, src);
    		} else {
    			err = br_ip4_multicast_add_group(br, port, group, vid,
    							 src);
    			if (err)
    				break;
    		}
    	}
    
    	return err;
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static int br_ip6_multicast_mld2_report(struct net_bridge *br,
    					struct net_bridge_port *port,
    					struct sk_buff *skb,
    					u16 vid)
    {
    	const unsigned char *src;
    	struct icmp6hdr *icmp6h;
    	struct mld2_grec *grec;
    	int i;
    	int len;
    	int num;
    	int err = 0;
    
    	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
    		return -EINVAL;
    
    	icmp6h = icmp6_hdr(skb);
    	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
    	len = skb_transport_offset(skb) + sizeof(*icmp6h);
    
    	for (i = 0; i < num; i++) {
    		__be16 *nsrcs, _nsrcs;
    
    		nsrcs = skb_header_pointer(skb,
    					   len + offsetof(struct mld2_grec,
    							  grec_nsrcs),
    					   sizeof(_nsrcs), &_nsrcs);
    		if (!nsrcs)
    			return -EINVAL;
    
    		if (!pskb_may_pull(skb,
    				   len + sizeof(*grec) +
    				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
    			return -EINVAL;
    
    		grec = (struct mld2_grec *)(skb->data + len);
    		len += sizeof(*grec) +
    		       sizeof(struct in6_addr) * ntohs(*nsrcs);
    
    		/* We treat these as MLDv1 reports for now. */
    		switch (grec->grec_type) {
    		case MLD2_MODE_IS_INCLUDE:
    		case MLD2_MODE_IS_EXCLUDE:
    		case MLD2_CHANGE_TO_INCLUDE:
    		case MLD2_CHANGE_TO_EXCLUDE:
    		case MLD2_ALLOW_NEW_SOURCES:
    		case MLD2_BLOCK_OLD_SOURCES:
    			break;
    
    		default:
    			continue;
    		}
    
    		src = eth_hdr(skb)->h_source;
    		if ((grec->grec_type == MLD2_CHANGE_TO_INCLUDE ||
    		     grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
    		    ntohs(*nsrcs) == 0) {
    			br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
    						     vid, src);
    		} else {
    			err = br_ip6_multicast_add_group(br, port,
    							 &grec->grec_mca, vid,
    							 src);
    			if (err)
    				break;
    		}
    	}
    
    	return err;
    }
    #endif
    
    static bool br_ip4_multicast_select_querier(struct net_bridge *br,
    					    struct net_bridge_port *port,
    					    __be32 saddr)
    {
    	if (!timer_pending(&br->ip4_own_query.timer) &&
    	    !timer_pending(&br->ip4_other_query.timer))
    		goto update;
    
    	if (!br->ip4_querier.addr.u.ip4)
    		goto update;
    
    	if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
    		goto update;
    
    	return false;
    
    update:
    	br->ip4_querier.addr.u.ip4 = saddr;
    
    	/* update protected by general multicast_lock by caller */
    	rcu_assign_pointer(br->ip4_querier.port, port);
    
    	return true;
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static bool br_ip6_multicast_select_querier(struct net_bridge *br,
    					    struct net_bridge_port *port,
    					    struct in6_addr *saddr)
    {
    	if (!timer_pending(&br->ip6_own_query.timer) &&
    	    !timer_pending(&br->ip6_other_query.timer))
    		goto update;
    
    	if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
    		goto update;
    
    	return false;
    
    update:
    	br->ip6_querier.addr.u.ip6 = *saddr;
    
    	/* update protected by general multicast_lock by caller */
    	rcu_assign_pointer(br->ip6_querier.port, port);
    
    	return true;
    }
    #endif
    
    static bool br_multicast_select_querier(struct net_bridge *br,
    					struct net_bridge_port *port,
    					struct br_ip *saddr)
    {
    	switch (saddr->proto) {
    	case htons(ETH_P_IP):
    		return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
    #endif
    	}
    
    	return false;
    }
    
    static void
    br_multicast_update_query_timer(struct net_bridge *br,
    				struct bridge_mcast_other_query *query,
    				unsigned long max_delay)
    {
    	if (!timer_pending(&query->timer))
    		query->delay_time = jiffies + max_delay;
    
    	mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
    }
    
    static void br_port_mc_router_state_change(struct net_bridge_port *p,
    					   bool is_mc_router)
    {
    	struct switchdev_attr attr = {
    		.orig_dev = p->dev,
    		.id = SWITCHDEV_ATTR_ID_PORT_MROUTER,
    		.flags = SWITCHDEV_F_DEFER,
    		.u.mrouter = is_mc_router,
    	};
    
    	switchdev_port_attr_set(p->dev, &attr);
    }
    
    /*
     * Add port to router_list
     *  list is maintained ordered by pointer value
     *  and locked by br->multicast_lock and RCU
     */
    static void br_multicast_add_router(struct net_bridge *br,
    				    struct net_bridge_port *port)
    {
    	struct net_bridge_port *p;
    	struct hlist_node *slot = NULL;
    
    	if (!hlist_unhashed(&port->rlist))
    		return;
    
    	hlist_for_each_entry(p, &br->router_list, rlist) {
    		if ((unsigned long) port >= (unsigned long) p)
    			break;
    		slot = &p->rlist;
    	}
    
    	if (slot)
    		hlist_add_behind_rcu(&port->rlist, slot);
    	else
    		hlist_add_head_rcu(&port->rlist, &br->router_list);
    	br_rtr_notify(br->dev, port, RTM_NEWMDB);
    	br_port_mc_router_state_change(port, true);
    }
    
    static void br_multicast_mark_router(struct net_bridge *br,
    				     struct net_bridge_port *port)
    {
    	unsigned long now = jiffies;
    
    	if (!port) {
    		if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
    			if (!timer_pending(&br->multicast_router_timer))
    				br_mc_router_state_change(br, true);
    			mod_timer(&br->multicast_router_timer,
    				  now + br->multicast_querier_interval);
    		}
    		return;
    	}
    
    	if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
    	    port->multicast_router == MDB_RTR_TYPE_PERM)
    		return;
    
    	br_multicast_add_router(br, port);
    
    	mod_timer(&port->multicast_router_timer,
    		  now + br->multicast_querier_interval);
    }
    
    static void br_multicast_query_received(struct net_bridge *br,
    					struct net_bridge_port *port,
    					struct bridge_mcast_other_query *query,
    					struct br_ip *saddr,
    					unsigned long max_delay)
    {
    	if (!br_multicast_select_querier(br, port, saddr))
    		return;
    
    	br_multicast_update_query_timer(br, query, max_delay);
    
    	/* Based on RFC4541, section 2.1.1 IGMP Forwarding Rules,
    	 * the arrival port for IGMP Queries where the source address
    	 * is 0.0.0.0 should not be added to router port list.
    	 */
    	if ((saddr->proto == htons(ETH_P_IP) && saddr->u.ip4) ||
    	    (saddr->proto == htons(ETH_P_IPV6) &&
    	     !ipv6_addr_any(&saddr->u.ip6)))
    		br_multicast_mark_router(br, port);
    }
    
    static void br_ip4_multicast_query(struct net_bridge *br,
    				   struct net_bridge_port *port,
    				   struct sk_buff *skb,
    				   u16 vid)
    {
    	const struct iphdr *iph = ip_hdr(skb);
    	struct igmphdr *ih = igmp_hdr(skb);
    	struct net_bridge_mdb_entry *mp;
    	struct igmpv3_query *ih3;
    	struct net_bridge_port_group *p;
    	struct net_bridge_port_group __rcu **pp;
    	struct br_ip saddr;
    	unsigned long max_delay;
    	unsigned long now = jiffies;
    	unsigned int offset = skb_transport_offset(skb);
    	__be32 group;
    
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) ||
    	    (port && port->state == BR_STATE_DISABLED))
    		goto out;
    
    	group = ih->group;
    
    	if (skb->len == offset + sizeof(*ih)) {
    		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
    
    		if (!max_delay) {
    			max_delay = 10 * HZ;
    			group = 0;
    		}
    	} else if (skb->len >= offset + sizeof(*ih3)) {
    		ih3 = igmpv3_query_hdr(skb);
    		if (ih3->nsrcs)
    			goto out;
    
    		max_delay = ih3->code ?
    			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
    	} else {
    		goto out;
    	}
    
    	if (!group) {
    		saddr.proto = htons(ETH_P_IP);
    		saddr.u.ip4 = iph->saddr;
    
    		br_multicast_query_received(br, port, &br->ip4_other_query,
    					    &saddr, max_delay);
    		goto out;
    	}
    
    	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
    	if (!mp)
    		goto out;
    
    	max_delay *= br->multicast_last_member_count;
    
    	if (mp->host_joined &&
    	    (timer_pending(&mp->timer) ?
    	     time_after(mp->timer.expires, now + max_delay) :
    	     try_to_del_timer_sync(&mp->timer) >= 0))
    		mod_timer(&mp->timer, now + max_delay);
    
    	for (pp = &mp->ports;
    	     (p = mlock_dereference(*pp, br)) != NULL;
    	     pp = &p->next) {
    		if (timer_pending(&p->timer) ?
    		    time_after(p->timer.expires, now + max_delay) :
    		    try_to_del_timer_sync(&p->timer) >= 0)
    			mod_timer(&p->timer, now + max_delay);
    	}
    
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static int br_ip6_multicast_query(struct net_bridge *br,
    				  struct net_bridge_port *port,
    				  struct sk_buff *skb,
    				  u16 vid)
    {
    	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
    	struct mld_msg *mld;
    	struct net_bridge_mdb_entry *mp;
    	struct mld2_query *mld2q;
    	struct net_bridge_port_group *p;
    	struct net_bridge_port_group __rcu **pp;
    	struct br_ip saddr;
    	unsigned long max_delay;
    	unsigned long now = jiffies;
    	unsigned int offset = skb_transport_offset(skb);
    	const struct in6_addr *group = NULL;
    	bool is_general_query;
    	int err = 0;
    
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) ||
    	    (port && port->state == BR_STATE_DISABLED))
    		goto out;
    
    	if (skb->len == offset + sizeof(*mld)) {
    		if (!pskb_may_pull(skb, offset + sizeof(*mld))) {
    			err = -EINVAL;
    			goto out;
    		}
    		mld = (struct mld_msg *) icmp6_hdr(skb);
    		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
    		if (max_delay)
    			group = &mld->mld_mca;
    	} else {
    		if (!pskb_may_pull(skb, offset + sizeof(*mld2q))) {
    			err = -EINVAL;
    			goto out;
    		}
    		mld2q = (struct mld2_query *)icmp6_hdr(skb);
    		if (!mld2q->mld2q_nsrcs)
    			group = &mld2q->mld2q_mca;
    
    		max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
    	}
    
    	is_general_query = group && ipv6_addr_any(group);
    
    	if (is_general_query) {
    		saddr.proto = htons(ETH_P_IPV6);
    		saddr.u.ip6 = ip6h->saddr;
    
    		br_multicast_query_received(br, port, &br->ip6_other_query,
    					    &saddr, max_delay);
    		goto out;
    	} else if (!group) {
    		goto out;
    	}
    
    	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
    	if (!mp)
    		goto out;
    
    	max_delay *= br->multicast_last_member_count;
    	if (mp->host_joined &&
    	    (timer_pending(&mp->timer) ?
    	     time_after(mp->timer.expires, now + max_delay) :
    	     try_to_del_timer_sync(&mp->timer) >= 0))
    		mod_timer(&mp->timer, now + max_delay);
    
    	for (pp = &mp->ports;
    	     (p = mlock_dereference(*pp, br)) != NULL;
    	     pp = &p->next) {
    		if (timer_pending(&p->timer) ?
    		    time_after(p->timer.expires, now + max_delay) :
    		    try_to_del_timer_sync(&p->timer) >= 0)
    			mod_timer(&p->timer, now + max_delay);
    	}
    
    out:
    	spin_unlock(&br->multicast_lock);
    	return err;
    }
    #endif
    
    static void
    br_multicast_leave_group(struct net_bridge *br,
    			 struct net_bridge_port *port,
    			 struct br_ip *group,
    			 struct bridge_mcast_other_query *other_query,
    			 struct bridge_mcast_own_query *own_query,
    			 const unsigned char *src)
    {
    	struct net_bridge_mdb_htable *mdb;
    	struct net_bridge_mdb_entry *mp;
    	struct net_bridge_port_group *p;
    	unsigned long now;
    	unsigned long time;
    
    	spin_lock(&br->multicast_lock);
    	if (!netif_running(br->dev) ||
    	    (port && port->state == BR_STATE_DISABLED))
    		goto out;
    
    	mdb = mlock_dereference(br->mdb, br);
    	mp = br_mdb_ip_get(mdb, group);
    	if (!mp)
    		goto out;
    
    	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
    		struct net_bridge_port_group __rcu **pp;
    
    		for (pp = &mp->ports;
    		     (p = mlock_dereference(*pp, br)) != NULL;
    		     pp = &p->next) {
    			if (!br_port_group_equal(p, port, src))
    				continue;
    
    			rcu_assign_pointer(*pp, p->next);
    			hlist_del_init(&p->mglist);
    			del_timer(&p->timer);
    			call_rcu_bh(&p->rcu, br_multicast_free_pg);
    			br_mdb_notify(br->dev, port, group, RTM_DELMDB,
    				      p->flags);
    
    			if (!mp->ports && !mp->host_joined &&
    			    netif_running(br->dev))
    				mod_timer(&mp->timer, jiffies);
    		}
    		goto out;
    	}
    
    	if (timer_pending(&other_query->timer))
    		goto out;
    
    	if (br_opt_get(br, BROPT_MULTICAST_QUERIER)) {
    		__br_multicast_send_query(br, port, &mp->addr);
    
    		time = jiffies + br->multicast_last_member_count *
    				 br->multicast_last_member_interval;
    
    		mod_timer(&own_query->timer, time);
    
    		for (p = mlock_dereference(mp->ports, br);
    		     p != NULL;
    		     p = mlock_dereference(p->next, br)) {
    			if (!br_port_group_equal(p, port, src))
    				continue;
    
    			if (!hlist_unhashed(&p->mglist) &&
    			    (timer_pending(&p->timer) ?
    			     time_after(p->timer.expires, time) :
    			     try_to_del_timer_sync(&p->timer) >= 0)) {
    				mod_timer(&p->timer, time);
    			}
    
    			break;
    		}
    	}
    
    	now = jiffies;
    	time = now + br->multicast_last_member_count *
    		     br->multicast_last_member_interval;
    
    	if (!port) {
    		if (mp->host_joined &&
    		    (timer_pending(&mp->timer) ?
    		     time_after(mp->timer.expires, time) :
    		     try_to_del_timer_sync(&mp->timer) >= 0)) {
    			mod_timer(&mp->timer, time);
    		}
    
    		goto out;
    	}
    
    	for (p = mlock_dereference(mp->ports, br);
    	     p != NULL;
    	     p = mlock_dereference(p->next, br)) {
    		if (p->port != port)
    			continue;
    
    		if (!hlist_unhashed(&p->mglist) &&
    		    (timer_pending(&p->timer) ?
    		     time_after(p->timer.expires, time) :
    		     try_to_del_timer_sync(&p->timer) >= 0)) {
    			mod_timer(&p->timer, time);
    		}
    
    		break;
    	}
    out:
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_ip4_multicast_leave_group(struct net_bridge *br,
    					 struct net_bridge_port *port,
    					 __be32 group,
    					 __u16 vid,
    					 const unsigned char *src)
    {
    	struct br_ip br_group;
    	struct bridge_mcast_own_query *own_query;
    
    	if (ipv4_is_local_multicast(group))
    		return;
    
    	own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
    
    	br_group.u.ip4 = group;
    	br_group.proto = htons(ETH_P_IP);
    	br_group.vid = vid;
    
    	br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
    				 own_query, src);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static void br_ip6_multicast_leave_group(struct net_bridge *br,
    					 struct net_bridge_port *port,
    					 const struct in6_addr *group,
    					 __u16 vid,
    					 const unsigned char *src)
    {
    	struct br_ip br_group;
    	struct bridge_mcast_own_query *own_query;
    
    	if (ipv6_addr_is_ll_all_nodes(group))
    		return;
    
    	own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
    
    	br_group.u.ip6 = *group;
    	br_group.proto = htons(ETH_P_IPV6);
    	br_group.vid = vid;
    
    	br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
    				 own_query, src);
    }
    #endif
    
    static void br_multicast_err_count(const struct net_bridge *br,
    				   const struct net_bridge_port *p,
    				   __be16 proto)
    {
    	struct bridge_mcast_stats __percpu *stats;
    	struct bridge_mcast_stats *pstats;
    
    	if (!br_opt_get(br, BROPT_MULTICAST_STATS_ENABLED))
    		return;
    
    	if (p)
    		stats = p->mcast_stats;
    	else
    		stats = br->mcast_stats;
    	if (WARN_ON(!stats))
    		return;
    
    	pstats = this_cpu_ptr(stats);
    
    	u64_stats_update_begin(&pstats->syncp);
    	switch (proto) {
    	case htons(ETH_P_IP):
    		pstats->mstats.igmp_parse_errors++;
    		break;
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		pstats->mstats.mld_parse_errors++;
    		break;
    #endif
    	}
    	u64_stats_update_end(&pstats->syncp);
    }
    
    static void br_multicast_pim(struct net_bridge *br,
    			     struct net_bridge_port *port,
    			     const struct sk_buff *skb)
    {
    	unsigned int offset = skb_transport_offset(skb);
    	struct pimhdr *pimhdr, _pimhdr;
    
    	pimhdr = skb_header_pointer(skb, offset, sizeof(_pimhdr), &_pimhdr);
    	if (!pimhdr || pim_hdr_version(pimhdr) != PIM_VERSION ||
    	    pim_hdr_type(pimhdr) != PIM_TYPE_HELLO)
    		return;
    
    	br_multicast_mark_router(br, port);
    }
    
    static int br_multicast_ipv4_rcv(struct net_bridge *br,
    				 struct net_bridge_port *port,
    				 struct sk_buff *skb,
    				 u16 vid)
    {
    	struct sk_buff *skb_trimmed = NULL;
    	const unsigned char *src;
    	struct igmphdr *ih;
    	int err;
    
    	err = ip_mc_check_igmp(skb, &skb_trimmed);
    
    	if (err == -ENOMSG) {
    		if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr)) {
    			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
    		} else if (pim_ipv4_all_pim_routers(ip_hdr(skb)->daddr)) {
    			if (ip_hdr(skb)->protocol == IPPROTO_PIM)
    				br_multicast_pim(br, port, skb);
    		}
    		return 0;
    	} else if (err < 0) {
    		br_multicast_err_count(br, port, skb->protocol);
    		return err;
    	}
    
    	ih = igmp_hdr(skb);
    	src = eth_hdr(skb)->h_source;
    	BR_INPUT_SKB_CB(skb)->igmp = ih->type;
    
    	switch (ih->type) {
    	case IGMP_HOST_MEMBERSHIP_REPORT:
    	case IGMPV2_HOST_MEMBERSHIP_REPORT:
    		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
    		err = br_ip4_multicast_add_group(br, port, ih->group, vid, src);
    		break;
    	case IGMPV3_HOST_MEMBERSHIP_REPORT:
    		err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
    		break;
    	case IGMP_HOST_MEMBERSHIP_QUERY:
    		br_ip4_multicast_query(br, port, skb_trimmed, vid);
    		break;
    	case IGMP_HOST_LEAVE_MESSAGE:
    		br_ip4_multicast_leave_group(br, port, ih->group, vid, src);
    		break;
    	}
    
    	if (skb_trimmed && skb_trimmed != skb)
    		kfree_skb(skb_trimmed);
    
    	br_multicast_count(br, port, skb, BR_INPUT_SKB_CB(skb)->igmp,
    			   BR_MCAST_DIR_RX);
    
    	return err;
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static int br_multicast_ipv6_rcv(struct net_bridge *br,
    				 struct net_bridge_port *port,
    				 struct sk_buff *skb,
    				 u16 vid)
    {
    	struct sk_buff *skb_trimmed = NULL;
    	const unsigned char *src;
    	struct mld_msg *mld;
    	int err;
    
    	err = ipv6_mc_check_mld(skb, &skb_trimmed);
    
    	if (err == -ENOMSG) {
    		if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
    			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
    		return 0;
    	} else if (err < 0) {
    		br_multicast_err_count(br, port, skb->protocol);
    		return err;
    	}
    
    	mld = (struct mld_msg *)skb_transport_header(skb);
    	BR_INPUT_SKB_CB(skb)->igmp = mld->mld_type;
    
    	switch (mld->mld_type) {
    	case ICMPV6_MGM_REPORT:
    		src = eth_hdr(skb)->h_source;
    		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
    		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid,
    						 src);
    		break;
    	case ICMPV6_MLD2_REPORT:
    		err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
    		break;
    	case ICMPV6_MGM_QUERY:
    		err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
    		break;
    	case ICMPV6_MGM_REDUCTION:
    		src = eth_hdr(skb)->h_source;
    		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid, src);
    		break;
    	}
    
    	if (skb_trimmed && skb_trimmed != skb)
    		kfree_skb(skb_trimmed);
    
    	br_multicast_count(br, port, skb, BR_INPUT_SKB_CB(skb)->igmp,
    			   BR_MCAST_DIR_RX);
    
    	return err;
    }
    #endif
    
    int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
    		     struct sk_buff *skb, u16 vid)
    {
    	int ret = 0;
    
    	BR_INPUT_SKB_CB(skb)->igmp = 0;
    	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
    
    	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
    		return 0;
    
    	switch (skb->protocol) {
    	case htons(ETH_P_IP):
    		ret = br_multicast_ipv4_rcv(br, port, skb, vid);
    		break;
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		ret = br_multicast_ipv6_rcv(br, port, skb, vid);
    		break;
    #endif
    	}
    
    	return ret;
    }
    
    static void br_multicast_query_expired(struct net_bridge *br,
    				       struct bridge_mcast_own_query *query,
    				       struct bridge_mcast_querier *querier)
    {
    	spin_lock(&br->multicast_lock);
    	if (query->startup_sent < br->multicast_startup_query_count)
    		query->startup_sent++;
    
    	RCU_INIT_POINTER(querier->port, NULL);
    	br_multicast_send_query(br, NULL, query);
    	spin_unlock(&br->multicast_lock);
    }
    
    static void br_ip4_multicast_query_expired(struct timer_list *t)
    {
    	struct net_bridge *br = from_timer(br, t, ip4_own_query.timer);
    
    	br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    static void br_ip6_multicast_query_expired(struct timer_list *t)
    {
    	struct net_bridge *br = from_timer(br, t, ip6_own_query.timer);
    
    	br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
    }
    #endif
    
    void br_multicast_init(struct net_bridge *br)
    {
    	br->hash_elasticity = 4;
    	br->hash_max = 512;
    
    	br->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
    	br->multicast_last_member_count = 2;
    	br->multicast_startup_query_count = 2;
    
    	br->multicast_last_member_interval = HZ;
    	br->multicast_query_response_interval = 10 * HZ;
    	br->multicast_startup_query_interval = 125 * HZ / 4;
    	br->multicast_query_interval = 125 * HZ;
    	br->multicast_querier_interval = 255 * HZ;
    	br->multicast_membership_interval = 260 * HZ;
    
    	br->ip4_other_query.delay_time = 0;
    	br->ip4_querier.port = NULL;
    	br->multicast_igmp_version = 2;
    #if IS_ENABLED(CONFIG_IPV6)
    	br->multicast_mld_version = 1;
    	br->ip6_other_query.delay_time = 0;
    	br->ip6_querier.port = NULL;
    #endif
    	br_opt_toggle(br, BROPT_MULTICAST_ENABLED, true);
    	br_opt_toggle(br, BROPT_HAS_IPV6_ADDR, true);
    
    	spin_lock_init(&br->multicast_lock);
    	timer_setup(&br->multicast_router_timer,
    		    br_multicast_local_router_expired, 0);
    	timer_setup(&br->ip4_other_query.timer,
    		    br_ip4_multicast_querier_expired, 0);
    	timer_setup(&br->ip4_own_query.timer,
    		    br_ip4_multicast_query_expired, 0);
    #if IS_ENABLED(CONFIG_IPV6)
    	timer_setup(&br->ip6_other_query.timer,
    		    br_ip6_multicast_querier_expired, 0);
    	timer_setup(&br->ip6_own_query.timer,
    		    br_ip6_multicast_query_expired, 0);
    #endif
    }
    
    static void __br_multicast_open(struct net_bridge *br,
    				struct bridge_mcast_own_query *query)
    {
    	query->startup_sent = 0;
    
    	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
    		return;
    
    	mod_timer(&query->timer, jiffies);
    }
    
    void br_multicast_open(struct net_bridge *br)
    {
    	__br_multicast_open(br, &br->ip4_own_query);
    #if IS_ENABLED(CONFIG_IPV6)
    	__br_multicast_open(br, &br->ip6_own_query);
    #endif
    }
    
    void br_multicast_stop(struct net_bridge *br)
    {
    	del_timer_sync(&br->multicast_router_timer);
    	del_timer_sync(&br->ip4_other_query.timer);
    	del_timer_sync(&br->ip4_own_query.timer);
    #if IS_ENABLED(CONFIG_IPV6)
    	del_timer_sync(&br->ip6_other_query.timer);
    	del_timer_sync(&br->ip6_own_query.timer);
    #endif
    }
    
    void br_multicast_dev_del(struct net_bridge *br)
    {
    	struct net_bridge_mdb_htable *mdb;
    	struct net_bridge_mdb_entry *mp;
    	struct hlist_node *n;
    	u32 ver;
    	int i;
    
    	spin_lock_bh(&br->multicast_lock);
    	mdb = mlock_dereference(br->mdb, br);
    	if (!mdb)
    		goto out;
    
    	br->mdb = NULL;
    
    	ver = mdb->ver;
    	for (i = 0; i < mdb->max; i++) {
    		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
    					  hlist[ver]) {
    			del_timer(&mp->timer);
    			call_rcu_bh(&mp->rcu, br_multicast_free_group);
    		}
    	}
    
    	if (mdb->old) {
    		spin_unlock_bh(&br->multicast_lock);
    		rcu_barrier_bh();
    		spin_lock_bh(&br->multicast_lock);
    		WARN_ON(mdb->old);
    	}
    
    	mdb->old = mdb;
    	call_rcu_bh(&mdb->rcu, br_mdb_free);
    
    out:
    	spin_unlock_bh(&br->multicast_lock);
    }
    
    int br_multicast_set_router(struct net_bridge *br, unsigned long val)
    {
    	int err = -EINVAL;
    
    	spin_lock_bh(&br->multicast_lock);
    
    	switch (val) {
    	case MDB_RTR_TYPE_DISABLED:
    	case MDB_RTR_TYPE_PERM:
    		br_mc_router_state_change(br, val == MDB_RTR_TYPE_PERM);
    		del_timer(&br->multicast_router_timer);
    		br->multicast_router = val;
    		err = 0;
    		break;
    	case MDB_RTR_TYPE_TEMP_QUERY:
    		if (br->multicast_router != MDB_RTR_TYPE_TEMP_QUERY)
    			br_mc_router_state_change(br, false);
    		br->multicast_router = val;
    		err = 0;
    		break;
    	}
    
    	spin_unlock_bh(&br->multicast_lock);
    
    	return err;
    }
    
    static void __del_port_router(struct net_bridge_port *p)
    {
    	if (hlist_unhashed(&p->rlist))
    		return;
    	hlist_del_init_rcu(&p->rlist);
    	br_rtr_notify(p->br->dev, p, RTM_DELMDB);
    	br_port_mc_router_state_change(p, false);
    
    	/* don't allow timer refresh */
    	if (p->multicast_router == MDB_RTR_TYPE_TEMP)
    		p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
    }
    
    int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
    {
    	struct net_bridge *br = p->br;
    	unsigned long now = jiffies;
    	int err = -EINVAL;
    
    	spin_lock(&br->multicast_lock);
    	if (p->multicast_router == val) {
    		/* Refresh the temp router port timer */
    		if (p->multicast_router == MDB_RTR_TYPE_TEMP)
    			mod_timer(&p->multicast_router_timer,
    				  now + br->multicast_querier_interval);
    		err = 0;
    		goto unlock;
    	}
    	switch (val) {
    	case MDB_RTR_TYPE_DISABLED:
    		p->multicast_router = MDB_RTR_TYPE_DISABLED;
    		__del_port_router(p);
    		del_timer(&p->multicast_router_timer);
    		break;
    	case MDB_RTR_TYPE_TEMP_QUERY:
    		p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
    		__del_port_router(p);
    		break;
    	case MDB_RTR_TYPE_PERM:
    		p->multicast_router = MDB_RTR_TYPE_PERM;
    		del_timer(&p->multicast_router_timer);
    		br_multicast_add_router(br, p);
    		break;
    	case MDB_RTR_TYPE_TEMP:
    		p->multicast_router = MDB_RTR_TYPE_TEMP;
    		br_multicast_mark_router(br, p);
    		break;
    	default:
    		goto unlock;
    	}
    	err = 0;
    unlock:
    	spin_unlock(&br->multicast_lock);
    
    	return err;
    }
    
    static void br_multicast_start_querier(struct net_bridge *br,
    				       struct bridge_mcast_own_query *query)
    {
    	struct net_bridge_port *port;
    
    	__br_multicast_open(br, query);
    
    	list_for_each_entry(port, &br->port_list, list) {
    		if (port->state == BR_STATE_DISABLED ||
    		    port->state == BR_STATE_BLOCKING)
    			continue;
    
    		if (query == &br->ip4_own_query)
    			br_multicast_enable(&port->ip4_own_query);
    #if IS_ENABLED(CONFIG_IPV6)
    		else
    			br_multicast_enable(&port->ip6_own_query);
    #endif
    	}
    }
    
    int br_multicast_toggle(struct net_bridge *br, unsigned long val)
    {
    	struct net_bridge_mdb_htable *mdb;
    	struct net_bridge_port *port;
    	int err = 0;
    
    	spin_lock_bh(&br->multicast_lock);
    	if (!!br_opt_get(br, BROPT_MULTICAST_ENABLED) == !!val)
    		goto unlock;
    
    	br_mc_disabled_update(br->dev, val);
    	br_opt_toggle(br, BROPT_MULTICAST_ENABLED, !!val);
    	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
    		goto unlock;
    
    	if (!netif_running(br->dev))
    		goto unlock;
    
    	mdb = mlock_dereference(br->mdb, br);
    	if (mdb) {
    		if (mdb->old) {
    			err = -EEXIST;
    rollback:
    			br_opt_toggle(br, BROPT_MULTICAST_ENABLED, false);
    			goto unlock;
    		}
    
    		err = br_mdb_rehash(&br->mdb, mdb->max,
    				    br->hash_elasticity);
    		if (err)
    			goto rollback;
    	}
    
    	br_multicast_open(br);
    	list_for_each_entry(port, &br->port_list, list)
    		__br_multicast_enable_port(port);
    
    unlock:
    	spin_unlock_bh(&br->multicast_lock);
    
    	return err;
    }
    
    bool br_multicast_enabled(const struct net_device *dev)
    {
    	struct net_bridge *br = netdev_priv(dev);
    
    	return !!br_opt_get(br, BROPT_MULTICAST_ENABLED);
    }
    EXPORT_SYMBOL_GPL(br_multicast_enabled);
    
    bool br_multicast_router(const struct net_device *dev)
    {
    	struct net_bridge *br = netdev_priv(dev);
    	bool is_router;
    
    	spin_lock_bh(&br->multicast_lock);
    	is_router = br_multicast_is_router(br);
    	spin_unlock_bh(&br->multicast_lock);
    	return is_router;
    }
    EXPORT_SYMBOL_GPL(br_multicast_router);
    
    int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
    {
    	unsigned long max_delay;
    
    	val = !!val;
    
    	spin_lock_bh(&br->multicast_lock);
    	if (br_opt_get(br, BROPT_MULTICAST_QUERIER) == val)
    		goto unlock;
    
    	br_opt_toggle(br, BROPT_MULTICAST_QUERIER, !!val);
    	if (!val)
    		goto unlock;
    
    	max_delay = br->multicast_query_response_interval;
    
    	if (!timer_pending(&br->ip4_other_query.timer))
    		br->ip4_other_query.delay_time = jiffies + max_delay;
    
    	br_multicast_start_querier(br, &br->ip4_own_query);
    
    #if IS_ENABLED(CONFIG_IPV6)
    	if (!timer_pending(&br->ip6_other_query.timer))
    		br->ip6_other_query.delay_time = jiffies + max_delay;
    
    	br_multicast_start_querier(br, &br->ip6_own_query);
    #endif
    
    unlock:
    	spin_unlock_bh(&br->multicast_lock);
    
    	return 0;
    }
    
    int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
    {
    	int err = -EINVAL;
    	u32 old;
    	struct net_bridge_mdb_htable *mdb;
    
    	spin_lock_bh(&br->multicast_lock);
    	if (!is_power_of_2(val))
    		goto unlock;
    
    	mdb = mlock_dereference(br->mdb, br);
    	if (mdb && val < mdb->size)
    		goto unlock;
    
    	err = 0;
    
    	old = br->hash_max;
    	br->hash_max = val;
    
    	if (mdb) {
    		if (mdb->old) {
    			err = -EEXIST;
    rollback:
    			br->hash_max = old;
    			goto unlock;
    		}
    
    		err = br_mdb_rehash(&br->mdb, br->hash_max,
    				    br->hash_elasticity);
    		if (err)
    			goto rollback;
    	}
    
    unlock:
    	spin_unlock_bh(&br->multicast_lock);
    
    	return err;
    }
    
    int br_multicast_set_igmp_version(struct net_bridge *br, unsigned long val)
    {
    	/* Currently we support only version 2 and 3 */
    	switch (val) {
    	case 2:
    	case 3:
    		break;
    	default:
    		return -EINVAL;
    	}
    
    	spin_lock_bh(&br->multicast_lock);
    	br->multicast_igmp_version = val;
    	spin_unlock_bh(&br->multicast_lock);
    
    	return 0;
    }
    
    #if IS_ENABLED(CONFIG_IPV6)
    int br_multicast_set_mld_version(struct net_bridge *br, unsigned long val)
    {
    	/* Currently we support version 1 and 2 */
    	switch (val) {
    	case 1:
    	case 2:
    		break;
    	default:
    		return -EINVAL;
    	}
    
    	spin_lock_bh(&br->multicast_lock);
    	br->multicast_mld_version = val;
    	spin_unlock_bh(&br->multicast_lock);
    
    	return 0;
    }
    #endif
    
    /**
     * br_multicast_list_adjacent - Returns snooped multicast addresses
     * @dev:	The bridge port adjacent to which to retrieve addresses
     * @br_ip_list:	The list to store found, snooped multicast IP addresses in
     *
     * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
     * snooping feature on all bridge ports of dev's bridge device, excluding
     * the addresses from dev itself.
     *
     * Returns the number of items added to br_ip_list.
     *
     * Notes:
     * - br_ip_list needs to be initialized by caller
     * - br_ip_list might contain duplicates in the end
     *   (needs to be taken care of by caller)
     * - br_ip_list needs to be freed by caller
     */
    int br_multicast_list_adjacent(struct net_device *dev,
    			       struct list_head *br_ip_list)
    {
    	struct net_bridge *br;
    	struct net_bridge_port *port;
    	struct net_bridge_port_group *group;
    	struct br_ip_list *entry;
    	int count = 0;
    
    	rcu_read_lock();
    	if (!br_ip_list || !br_port_exists(dev))
    		goto unlock;
    
    	port = br_port_get_rcu(dev);
    	if (!port || !port->br)
    		goto unlock;
    
    	br = port->br;
    
    	list_for_each_entry_rcu(port, &br->port_list, list) {
    		if (!port->dev || port->dev == dev)
    			continue;
    
    		hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
    			entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
    			if (!entry)
    				goto unlock;
    
    			entry->addr = group->addr;
    			list_add(&entry->list, br_ip_list);
    			count++;
    		}
    	}
    
    unlock:
    	rcu_read_unlock();
    	return count;
    }
    EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
    
    /**
     * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
     * @dev: The bridge port providing the bridge on which to check for a querier
     * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
     *
     * Checks whether the given interface has a bridge on top and if so returns
     * true if a valid querier exists anywhere on the bridged link layer.
     * Otherwise returns false.
     */
    bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
    {
    	struct net_bridge *br;
    	struct net_bridge_port *port;
    	struct ethhdr eth;
    	bool ret = false;
    
    	rcu_read_lock();
    	if (!br_port_exists(dev))
    		goto unlock;
    
    	port = br_port_get_rcu(dev);
    	if (!port || !port->br)
    		goto unlock;
    
    	br = port->br;
    
    	memset(&eth, 0, sizeof(eth));
    	eth.h_proto = htons(proto);
    
    	ret = br_multicast_querier_exists(br, &eth);
    
    unlock:
    	rcu_read_unlock();
    	return ret;
    }
    EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
    
    /**
     * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
     * @dev: The bridge port adjacent to which to check for a querier
     * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
     *
     * Checks whether the given interface has a bridge on top and if so returns
     * true if a selected querier is behind one of the other ports of this
     * bridge. Otherwise returns false.
     */
    bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
    {
    	struct net_bridge *br;
    	struct net_bridge_port *port;
    	bool ret = false;
    
    	rcu_read_lock();
    	if (!br_port_exists(dev))
    		goto unlock;
    
    	port = br_port_get_rcu(dev);
    	if (!port || !port->br)
    		goto unlock;
    
    	br = port->br;
    
    	switch (proto) {
    	case ETH_P_IP:
    		if (!timer_pending(&br->ip4_other_query.timer) ||
    		    rcu_dereference(br->ip4_querier.port) == port)
    			goto unlock;
    		break;
    #if IS_ENABLED(CONFIG_IPV6)
    	case ETH_P_IPV6:
    		if (!timer_pending(&br->ip6_other_query.timer) ||
    		    rcu_dereference(br->ip6_querier.port) == port)
    			goto unlock;
    		break;
    #endif
    	default:
    		goto unlock;
    	}
    
    	ret = true;
    unlock:
    	rcu_read_unlock();
    	return ret;
    }
    EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);
    
    static void br_mcast_stats_add(struct bridge_mcast_stats __percpu *stats,
    			       const struct sk_buff *skb, u8 type, u8 dir)
    {
    	struct bridge_mcast_stats *pstats = this_cpu_ptr(stats);
    	__be16 proto = skb->protocol;
    	unsigned int t_len;
    
    	u64_stats_update_begin(&pstats->syncp);
    	switch (proto) {
    	case htons(ETH_P_IP):
    		t_len = ntohs(ip_hdr(skb)->tot_len) - ip_hdrlen(skb);
    		switch (type) {
    		case IGMP_HOST_MEMBERSHIP_REPORT:
    			pstats->mstats.igmp_v1reports[dir]++;
    			break;
    		case IGMPV2_HOST_MEMBERSHIP_REPORT:
    			pstats->mstats.igmp_v2reports[dir]++;
    			break;
    		case IGMPV3_HOST_MEMBERSHIP_REPORT:
    			pstats->mstats.igmp_v3reports[dir]++;
    			break;
    		case IGMP_HOST_MEMBERSHIP_QUERY:
    			if (t_len != sizeof(struct igmphdr)) {
    				pstats->mstats.igmp_v3queries[dir]++;
    			} else {
    				unsigned int offset = skb_transport_offset(skb);
    				struct igmphdr *ih, _ihdr;
    
    				ih = skb_header_pointer(skb, offset,
    							sizeof(_ihdr), &_ihdr);
    				if (!ih)
    					break;
    				if (!ih->code)
    					pstats->mstats.igmp_v1queries[dir]++;
    				else
    					pstats->mstats.igmp_v2queries[dir]++;
    			}
    			break;
    		case IGMP_HOST_LEAVE_MESSAGE:
    			pstats->mstats.igmp_leaves[dir]++;
    			break;
    		}
    		break;
    #if IS_ENABLED(CONFIG_IPV6)
    	case htons(ETH_P_IPV6):
    		t_len = ntohs(ipv6_hdr(skb)->payload_len) +
    			sizeof(struct ipv6hdr);
    		t_len -= skb_network_header_len(skb);
    		switch (type) {
    		case ICMPV6_MGM_REPORT:
    			pstats->mstats.mld_v1reports[dir]++;
    			break;
    		case ICMPV6_MLD2_REPORT:
    			pstats->mstats.mld_v2reports[dir]++;
    			break;
    		case ICMPV6_MGM_QUERY:
    			if (t_len != sizeof(struct mld_msg))
    				pstats->mstats.mld_v2queries[dir]++;
    			else
    				pstats->mstats.mld_v1queries[dir]++;
    			break;
    		case ICMPV6_MGM_REDUCTION:
    			pstats->mstats.mld_leaves[dir]++;
    			break;
    		}
    		break;
    #endif /* CONFIG_IPV6 */
    	}
    	u64_stats_update_end(&pstats->syncp);
    }
    
    void br_multicast_count(struct net_bridge *br, const struct net_bridge_port *p,
    			const struct sk_buff *skb, u8 type, u8 dir)
    {
    	struct bridge_mcast_stats __percpu *stats;
    
    	/* if multicast_disabled is true then igmp type can't be set */
    	if (!type || !br_opt_get(br, BROPT_MULTICAST_STATS_ENABLED))
    		return;
    
    	if (p)
    		stats = p->mcast_stats;
    	else
    		stats = br->mcast_stats;
    	if (WARN_ON(!stats))
    		return;
    
    	br_mcast_stats_add(stats, skb, type, dir);
    }
    
    int br_multicast_init_stats(struct net_bridge *br)
    {
    	br->mcast_stats = netdev_alloc_pcpu_stats(struct bridge_mcast_stats);
    	if (!br->mcast_stats)
    		return -ENOMEM;
    
    	return 0;
    }
    
    void br_multicast_uninit_stats(struct net_bridge *br)
    {
    	free_percpu(br->mcast_stats);
    }
    
    static void mcast_stats_add_dir(u64 *dst, u64 *src)
    {
    	dst[BR_MCAST_DIR_RX] += src[BR_MCAST_DIR_RX];
    	dst[BR_MCAST_DIR_TX] += src[BR_MCAST_DIR_TX];
    }
    
    void br_multicast_get_stats(const struct net_bridge *br,
    			    const struct net_bridge_port *p,
    			    struct br_mcast_stats *dest)
    {
    	struct bridge_mcast_stats __percpu *stats;
    	struct br_mcast_stats tdst;
    	int i;
    
    	memset(dest, 0, sizeof(*dest));
    	if (p)
    		stats = p->mcast_stats;
    	else
    		stats = br->mcast_stats;
    	if (WARN_ON(!stats))
    		return;
    
    	memset(&tdst, 0, sizeof(tdst));
    	for_each_possible_cpu(i) {
    		struct bridge_mcast_stats *cpu_stats = per_cpu_ptr(stats, i);
    		struct br_mcast_stats temp;
    		unsigned int start;
    
    		do {
    			start = u64_stats_fetch_begin_irq(&cpu_stats->syncp);
    			memcpy(&temp, &cpu_stats->mstats, sizeof(temp));
    		} while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, start));
    
    		mcast_stats_add_dir(tdst.igmp_v1queries, temp.igmp_v1queries);
    		mcast_stats_add_dir(tdst.igmp_v2queries, temp.igmp_v2queries);
    		mcast_stats_add_dir(tdst.igmp_v3queries, temp.igmp_v3queries);
    		mcast_stats_add_dir(tdst.igmp_leaves, temp.igmp_leaves);
    		mcast_stats_add_dir(tdst.igmp_v1reports, temp.igmp_v1reports);
    		mcast_stats_add_dir(tdst.igmp_v2reports, temp.igmp_v2reports);
    		mcast_stats_add_dir(tdst.igmp_v3reports, temp.igmp_v3reports);
    		tdst.igmp_parse_errors += temp.igmp_parse_errors;
    
    		mcast_stats_add_dir(tdst.mld_v1queries, temp.mld_v1queries);
    		mcast_stats_add_dir(tdst.mld_v2queries, temp.mld_v2queries);
    		mcast_stats_add_dir(tdst.mld_leaves, temp.mld_leaves);
    		mcast_stats_add_dir(tdst.mld_v1reports, temp.mld_v1reports);
    		mcast_stats_add_dir(tdst.mld_v2reports, temp.mld_v2reports);
    		tdst.mld_parse_errors += temp.mld_parse_errors;
    	}
    	memcpy(dest, &tdst, sizeof(*dest));
    }