--- zzzz-none-000/linux-4.4.60/net/bridge/br_multicast.c	2017-04-08 07:53:53.000000000 +0000
+++ wasp-540e-714/linux-4.4.60/net/bridge/br_multicast.c	2019-07-03 09:21:34.000000000 +0000
@@ -42,11 +42,13 @@
 static void br_ip4_multicast_leave_group(struct net_bridge *br,
 					 struct net_bridge_port *port,
 					 __be32 group,
+					 const struct ethhdr *eth,
 					 __u16 vid);
 #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,
+					 const struct ethhdr *eth,
 					 __u16 vid);
 #endif
 unsigned int br_mdb_rehash_seq;
@@ -218,14 +220,48 @@
 	return maxlen > elasticity ? -EINVAL : 0;
 }
 
+static void free_recipients(struct net_bridge_port_group *p)
+{
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+	struct net_bridge_group_recipient *recp, *temp;
+
+	recp = container_of(p->free_start, struct net_bridge_group_recipient, list);
+	list_for_each_entry_safe_from(recp, temp, &p->recipients, list)
+		kfree(recp);
+#endif
+}
+
 void br_multicast_free_pg(struct rcu_head *head)
 {
 	struct net_bridge_port_group *p =
 		container_of(head, struct net_bridge_port_group, rcu);
 
+	free_recipients(p);
 	kfree(p);
 }
 
+void delete_recipients(struct net_bridge_port_group *p)
+{
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+	struct net_bridge_group_recipient *pos;
+	list_for_each_entry(pos, &p->recipients, list) {
+		hlist_del(&pos->fdb_list);
+	}
+	/* this works even if recipients is empty, free_recipients() can catch this */
+	p->free_start = p->recipients.next;
+	INIT_LIST_HEAD_RCU(&p->recipients);
+#endif
+}
+
+/* must be called under the bridge's multicast lock */
+void br_multicast_delete_pg(struct net_bridge_port_group *p)
+{
+	hlist_del_init(&p->mglist);
+	del_timer(&p->timer);
+	delete_recipients(p);
+	call_rcu_bh(&p->rcu, br_multicast_free_pg);
+}
+
 static void br_multicast_free_group(struct rcu_head *head)
 {
 	struct net_bridge_mdb_entry *mp =
@@ -281,16 +317,20 @@
 			continue;
 
 		rcu_assign_pointer(*pp, p->next);
-		hlist_del_init(&p->mglist);
-		del_timer(&p->timer);
+		br_multicast_delete_pg(p);
 		br_mdb_notify(br->dev, p->port, &pg->addr, RTM_DELMDB,
 			      p->state);
-		call_rcu_bh(&p->rcu, br_multicast_free_pg);
 
 		if (!mp->ports && !mp->mglist &&
 		    netif_running(br->dev))
 			mod_timer(&mp->timer, jiffies);
 
+#ifdef CONFIG_AVM_PA
+		/* Must re-learn multicast sessions because of removed port group,
+		 * otherwise avm_pa continues to forward to that port */
+		if (p->addr.proto == __constant_htons(ETH_P_IP))
+			avm_pa_flush_multicast_sessions_for_group(p->addr.u.ip4);
+#endif
 		return;
 	}
 
@@ -665,14 +705,92 @@
 	p->state = state;
 	rcu_assign_pointer(p->next, next);
 	hlist_add_head(&p->mglist, &port->mglist);
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+	INIT_LIST_HEAD(&p->recipients);
+#endif
 	setup_timer(&p->timer, br_multicast_port_group_expired,
 		    (unsigned long)p);
 	return p;
 }
 
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+/* must be called under the bridge's multicast lock */
+static int add_group_recipient(struct net_bridge *br,
+			       struct net_bridge_port_group *group,
+			       const struct ethhdr *eth)
+{
+	struct net_bridge_group_recipient *p, *recp;
+	struct net_bridge_fdb_entry *fdb;
+
+	/* find the fdb entry that corresponds to the source address */
+	fdb = __br_fdb_get(br, eth->h_source, group->addr.vid);
+	BUG_ON(fdb == NULL);
+
+	/* never add twice */
+	list_for_each_entry(p, &group->recipients, list) {
+		if (fdb == rcu_dereference(p->recipient))
+			return 0;
+	}
+
+	recp = kzalloc(sizeof(*recp), GFP_ATOMIC);
+	if (unlikely(!recp))
+		return -ENOMEM;
+
+	recp->recipient = fdb;
+	recp->group = group;
+	recp->group->num_recipients++;
+	list_add_rcu(&recp->list, &recp->group->recipients);
+	/* To be able to remove this fdb from the recipents when it's freed the fdb
+	 * has a list of all net_bridge_group_recipient it is part of */
+	hlist_add_head(&recp->fdb_list, &fdb->pg_list);
+	return 0;
+}
+
+
+static void br_multicast_free_recipient(struct rcu_head *head)
+{
+	struct net_bridge_group_recipient *recp =
+		container_of(head, struct net_bridge_group_recipient, rcu);
+
+	kfree(recp);
+}
+
+/* Deletes the recipient from all lists and schedules the rcu callback to free it.
+ * must be called under the bridge's multicast lock */
+void br_multicast_delete_recipient(struct net_bridge_group_recipient *p)
+{
+	BUG_ON(p->group->num_recipients == 0);
+
+	hlist_del(&p->fdb_list);
+	list_del_rcu(&p->list);
+	p->group->num_recipients--;
+	call_rcu_bh(&p->rcu, &br_multicast_free_recipient);
+}
+
+/* must be called under the bridge's multicast lock */
+static int del_group_recipient(struct net_bridge *br,
+			       struct net_bridge_port_group *group,
+			       const struct ethhdr *eth)
+{
+	struct net_bridge_group_recipient *p, *temp;
+	struct net_bridge_fdb_entry *fdb;
+
+	/* find the fdb entry that corresponds to the source address */
+	fdb = __br_fdb_get(br, eth->h_source, group->addr.vid);
+	BUG_ON(fdb == NULL);
+
+	list_for_each_entry_safe(p, temp, &group->recipients, list) {
+		if (fdb == p->recipient)
+			br_multicast_delete_recipient(p);
+	}
+	return 0;
+}
+#endif
+
 static int br_multicast_add_group(struct net_bridge *br,
 				  struct net_bridge_port *port,
-				  struct br_ip *group)
+				  struct br_ip *group,
+				  const struct ethhdr *eth)
 {
 	struct net_bridge_mdb_entry *mp;
 	struct net_bridge_port_group *p;
@@ -712,6 +830,16 @@
 	br_mdb_notify(br->dev, port, group, RTM_NEWMDB, MDB_TEMPORARY);
 
 found:
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+	add_group_recipient(br, p, eth);
+#endif
+#ifdef CONFIG_AVM_PA
+	/* Must re-learn multicast sessions because of newly added port group,
+	 * otherwise avm_pa continues to forward only to existing egress ports and
+	 * not this one */
+	if (group->proto == __constant_htons(ETH_P_IP))
+		avm_pa_flush_multicast_sessions_for_group(group->u.ip4);
+#endif
 	mod_timer(&p->timer, now + br->multicast_membership_interval);
 out:
 	err = 0;
@@ -724,6 +852,7 @@
 static int br_ip4_multicast_add_group(struct net_bridge *br,
 				      struct net_bridge_port *port,
 				      __be32 group,
+				      const struct ethhdr *eth,
 				      __u16 vid)
 {
 	struct br_ip br_group;
@@ -735,13 +864,14 @@
 	br_group.proto = htons(ETH_P_IP);
 	br_group.vid = vid;
 
-	return br_multicast_add_group(br, port, &br_group);
+	return br_multicast_add_group(br, port, &br_group, eth);
 }
 
 #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,
+				      const struct ethhdr *eth,
 				      __u16 vid)
 {
 	struct br_ip br_group;
@@ -753,7 +883,7 @@
 	br_group.proto = htons(ETH_P_IPV6);
 	br_group.vid = vid;
 
-	return br_multicast_add_group(br, port, &br_group);
+	return br_multicast_add_group(br, port, &br_group, eth);
 }
 #endif
 
@@ -832,7 +962,7 @@
 
 	if (port) {
 		skb->dev = port->dev;
-		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
+		BR_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
 			dev_net(port->dev), NULL, skb, NULL, skb->dev,
 			br_dev_queue_push_xmit);
 	} else {
@@ -916,6 +1046,10 @@
 
 void br_multicast_add_port(struct net_bridge_port *port)
 {
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+	port->multicast_to_unicast_threshold =
+		CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST_DEFAULT_THRESHOLD;
+#endif
 	port->multicast_router = 1;
 
 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
@@ -1001,6 +1135,7 @@
 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 					 struct net_bridge_port *port,
 					 struct sk_buff *skb,
+					 const struct ethhdr *eth,
 					 u16 vid)
 {
 	struct igmpv3_report *ih;
@@ -1046,9 +1181,9 @@
 		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);
+			br_ip4_multicast_leave_group(br, port, group, eth, vid);
 		} else {
-			err = br_ip4_multicast_add_group(br, port, group, vid);
+			err = br_ip4_multicast_add_group(br, port, group, eth, vid);
 			if (err)
 				break;
 		}
@@ -1061,6 +1196,7 @@
 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 					struct net_bridge_port *port,
 					struct sk_buff *skb,
+					const struct ethhdr *eth,
 					u16 vid)
 {
 	struct icmp6hdr *icmp6h;
@@ -1113,11 +1249,9 @@
 		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);
+			br_ip6_multicast_leave_group(br, port, &grec->grec_mca, eth, vid);
 		} else {
-			err = br_ip6_multicast_add_group(br, port,
-							 &grec->grec_mca, vid);
+			err = br_ip6_multicast_add_group(br, port, &grec->grec_mca, eth, vid);
 			if (err)
 				break;
 		}
@@ -1431,6 +1565,7 @@
 br_multicast_leave_group(struct net_bridge *br,
 			 struct net_bridge_port *port,
 			 struct br_ip *group,
+			 const struct ethhdr *eth,
 			 struct bridge_mcast_other_query *other_query,
 			 struct bridge_mcast_own_query *own_query)
 {
@@ -1460,9 +1595,7 @@
 				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_multicast_delete_pg(p);
 			br_mdb_notify(br->dev, port, group, RTM_DELMDB,
 				      p->state);
 
@@ -1522,6 +1655,10 @@
 		if (p->port != port)
 			continue;
 
+#ifdef CONFIG_AVM_BRIDGE_MULTICAST_TO_UNICAST
+		del_group_recipient(br, p, eth);
+#endif
+
 		if (!hlist_unhashed(&p->mglist) &&
 		    (timer_pending(&p->timer) ?
 		     time_after(p->timer.expires, time) :
@@ -1538,6 +1675,7 @@
 static void br_ip4_multicast_leave_group(struct net_bridge *br,
 					 struct net_bridge_port *port,
 					 __be32 group,
+					 const struct ethhdr *eth,
 					 __u16 vid)
 {
 	struct br_ip br_group;
@@ -1552,7 +1690,7 @@
 	br_group.proto = htons(ETH_P_IP);
 	br_group.vid = vid;
 
-	br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
+	br_multicast_leave_group(br, port, &br_group, eth, &br->ip4_other_query,
 				 own_query);
 }
 
@@ -1560,6 +1698,7 @@
 static void br_ip6_multicast_leave_group(struct net_bridge *br,
 					 struct net_bridge_port *port,
 					 const struct in6_addr *group,
+					 const struct ethhdr *eth,
 					 __u16 vid)
 {
 	struct br_ip br_group;
@@ -1574,7 +1713,7 @@
 	br_group.proto = htons(ETH_P_IPV6);
 	br_group.vid = vid;
 
-	br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
+	br_multicast_leave_group(br, port, &br_group, eth, &br->ip6_other_query,
 				 own_query);
 }
 #endif
@@ -1585,10 +1724,12 @@
 				 u16 vid)
 {
 	struct sk_buff *skb_trimmed = NULL;
+	const struct ethhdr *eth;
 	struct igmphdr *ih;
 	int err;
 
 	err = ip_mc_check_igmp(skb, &skb_trimmed);
+	eth = eth_hdr(skb);
 
 	if (err == -ENOMSG) {
 		if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr))
@@ -1605,16 +1746,16 @@
 	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);
+		err = br_ip4_multicast_add_group(br, port, ih->group, eth, vid);
 		break;
 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
-		err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
+		err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, eth, 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);
+		br_ip4_multicast_leave_group(br, port, ih->group, eth, vid);
 		break;
 	}
 
@@ -1631,10 +1772,12 @@
 				 u16 vid)
 {
 	struct sk_buff *skb_trimmed = NULL;
+	const struct ethhdr *eth;
 	struct mld_msg *mld;
 	int err;
 
 	err = ipv6_mc_check_mld(skb, &skb_trimmed);
+	eth = eth_hdr(skb);
 
 	if (err == -ENOMSG) {
 		if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
@@ -1650,16 +1793,16 @@
 	switch (mld->mld_type) {
 	case ICMPV6_MGM_REPORT:
 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
-		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
+		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, eth, vid);
 		break;
 	case ICMPV6_MLD2_REPORT:
-		err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
+		err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, eth, vid);
 		break;
 	case ICMPV6_MGM_QUERY:
 		err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
 		break;
 	case ICMPV6_MGM_REDUCTION:
-		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
+		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, eth, vid);
 		break;
 	}
 
@@ -1806,6 +1949,10 @@
 
 	br->mdb = NULL;
 
+#ifdef CONFIG_AVM_PA
+	avm_pa_flush_multicast_sessions();
+#endif
+
 	ver = mdb->ver;
 	for (i = 0; i < mdb->max; i++) {
 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],