text: /*
   * 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->multicast_disabled)
  		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(unsigned long data)
  {
  	struct net_bridge_mdb_entry *mp = (void *)data;
  	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->mglist = false;
  
  	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->mglist &&
  		    netif_running(br->dev))
  			mod_timer(&mp->timer, jiffies);
  
  		return;
  	}
  
  	WARN_ON(1);
  }
  
  static void br_multicast_port_group_expired(unsigned long data)
  {
  	struct net_bridge_port_group *pg = (void *)data;
  	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 = kzalloc(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->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->has_ipv6_addr = 0;
  		return NULL;
  	}
  
  	br->has_ipv6_addr = 1;
  	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->multicast_disabled = 1;
  			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;
  	setup_timer(&mp->timer, br_multicast_group_expired,
  		    (unsigned long)mp);
  
  	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);
  	setup_timer(&p->timer, br_multicast_port_group_expired,
  		    (unsigned long)p);
  
  	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) {
  		mp->mglist = true;
  		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(unsigned long data)
  {
  	struct net_bridge_port *port = (void *)data;
  	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_multicast_local_router_expired(unsigned long data)
  {
  }
  
  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->multicast_disabled)
  		goto out;
  
  	br_multicast_start_querier(br, query);
  
  out:
  	spin_unlock(&br->multicast_lock);
  }
  
  static void br_ip4_multicast_querier_expired(unsigned long data)
  {
  	struct net_bridge *br = (void *)data;
  
  	br_multicast_querier_expired(br, &br->ip4_own_query);
  }
  
  #if IS_ENABLED(CONFIG_IPV6)
  static void br_ip6_multicast_querier_expired(unsigned long data)
  {
  	struct net_bridge *br = (void *)data;
  
  	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->multicast_disabled ||
  	    !br->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(unsigned long data)
  {
  	struct net_bridge_port *port = (void *)data;
  
  	br_multicast_port_query_expired(port, &port->ip4_own_query);
  }
  
  #if IS_ENABLED(CONFIG_IPV6)
  static void br_ip6_multicast_port_query_expired(unsigned long data)
  {
  	struct net_bridge_port *port = (void *)data;
  
  	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;
  
  	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
  		    (unsigned long)port);
  	setup_timer(&port->ip4_own_query.timer,
  		    br_ip4_multicast_port_query_expired, (unsigned long)port);
  #if IS_ENABLED(CONFIG_IPV6)
  	setup_timer(&port->ip6_own_query.timer,
  		    br_ip6_multicast_port_query_expired, (unsigned long)port);
  #endif
  	br_mc_disabled_update(port->dev, port->br->multicast_disabled);
  
  	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->multicast_disabled || !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)
  			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);
  	br_multicast_mark_router(br, port);
  }
  
  static int 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;
  	int err = 0;
  
  	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->mglist &&
  	    (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;
  }
  
  #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->mglist &&
  	    (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->mglist &&
  			    netif_running(br->dev))
  				mod_timer(&mp->timer, jiffies);
  		}
  		goto out;
  	}
  
  	if (timer_pending(&other_query->timer))
  		goto out;
  
  	if (br->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->mglist &&
  		    (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->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:
  		err = 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->multicast_disabled)
  		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(unsigned long data)
  {
  	struct net_bridge *br = (void *)data;
  
  	br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
  }
  
  #if IS_ENABLED(CONFIG_IPV6)
  static void br_ip6_multicast_query_expired(unsigned long data)
  {
  	struct net_bridge *br = (void *)data;
  
  	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_querier = 0;
  	br->multicast_query_use_ifaddr = 0;
  	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->has_ipv6_addr = 1;
  
  	spin_lock_init(&br->multicast_lock);
  	setup_timer(&br->multicast_router_timer,
  		    br_multicast_local_router_expired, 0);
  	setup_timer(&br->ip4_other_query.timer,
  		    br_ip4_multicast_querier_expired, (unsigned long)br);
  	setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
  		    (unsigned long)br);
  #if IS_ENABLED(CONFIG_IPV6)
  	setup_timer(&br->ip6_other_query.timer,
  		    br_ip6_multicast_querier_expired, (unsigned long)br);
  	setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
  		    (unsigned long)br);
  #endif
  }
  
  static void __br_multicast_open(struct net_bridge *br,
  				struct bridge_mcast_own_query *query)
  {
  	query->startup_sent = 0;
  
  	if (br->multicast_disabled)
  		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);
  
  	free_percpu(br->mcast_stats);
  }
  
  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:
  		del_timer(&br->multicast_router_timer);
  		/* fall through */
  	case MDB_RTR_TYPE_TEMP_QUERY:
  		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->multicast_disabled == !val)
  		goto unlock;
  
  	br_mc_disabled_update(br->dev, !val);
  	br->multicast_disabled = !val;
  	if (br->multicast_disabled)
  		goto unlock;
  
  	if (!netif_running(br->dev))
  		goto unlock;
  
  	mdb = mlock_dereference(br->mdb, br);
  	if (mdb) {
  		if (mdb->old) {
  			err = -EEXIST;
  rollback:
  			br->multicast_disabled = !!val;
  			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;
  }
  
  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->multicast_querier == val)
  		goto unlock;
  
  	br->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->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;
  }
  
  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));
  }
  