bridge: multicast: fix handling of temp and perm entries

When the bridge (or port) is brought down/up flush only temp entries and
leave the perm ones. Flush perm entries only when deleting the bridge
device or the associated port.

Signed-off-by: Satish Ashok <sashok@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_if.c

@@ -281,6 +281,7 @@ void br_dev_delete(struct net_device *dev, struct list_head *head)
 	br_fdb_delete_by_port(br, NULL, 0, 1);
 
 	br_vlan_flush(br);
+	br_multicast_dev_del(br);
 	del_timer_sync(&br->gc_timer);
 
 	br_sysfs_delbr(br->dev);

net/bridge/br_multicast.c

@@ -916,6 +916,15 @@ void br_multicast_add_port(struct net_bridge_port *port)
 
 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);
 }
 
@@ -955,7 +964,8 @@ void br_multicast_disable_port(struct net_bridge_port *port)
 
 	spin_lock(&br->multicast_lock);
 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
-		br_multicast_del_pg(br, pg);
+		if (pg->state == MDB_TEMPORARY)
+			br_multicast_del_pg(br, pg);
 
 	if (!hlist_unhashed(&port->rlist))
 		hlist_del_init_rcu(&port->rlist);
@@ -1732,19 +1742,22 @@ void br_multicast_open(struct net_bridge *br)
 
 void br_multicast_stop(struct net_bridge *br)
 {
-	struct net_bridge_mdb_htable *mdb;
-	struct net_bridge_mdb_entry *mp;
-	struct hlist_node *n;
-	u32 ver;
-	int i;
-
 	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);

net/bridge/br_private.h

@@ -466,6 +466,7 @@ void br_multicast_disable_port(struct net_bridge_port *port);
 void br_multicast_init(struct net_bridge *br);
 void br_multicast_open(struct net_bridge *br);
 void br_multicast_stop(struct net_bridge *br);
+void br_multicast_dev_del(struct net_bridge *br);
 void br_multicast_deliver(struct net_bridge_mdb_entry *mdst,
 			  struct sk_buff *skb);
 void br_multicast_forward(struct net_bridge_mdb_entry *mdst,