[PATCH 3.16.y-ckt 175/185] bridge: multicast: restore router configuration on port link down/up

[Luis Henriques]

3.16.7-ckt15 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Satish Ashok <sashok at cumulusnetworks.com>

commit 754bc547f0a79f7568b5b81c7fc0a8d044a6571a upstream.

When a port goes through a link down/up the multicast router configuration
is not restored.

Signed-off-by: Satish Ashok <sashok at cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
Fixes: 0909e11758bd ("bridge: Add multicast_router sysfs entries")
Acked-by: Herbert Xu <herbert at gondor.apana.org.au>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/bridge/br_multicast.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 32de99bf6e42..46ac609d0882 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -37,6 +37,8 @@
 
 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);
 unsigned int br_mdb_rehash_seq;
 
 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
@@ -935,6 +937,8 @@ void br_multicast_enable_port(struct net_bridge_port *port)
 #if IS_ENABLED(CONFIG_IPV6)
 	br_multicast_enable(&port->ip6_own_query);
 #endif
+	if (port->multicast_router == 2 && hlist_unhashed(&port->rlist))
+		br_multicast_add_router(br, port);
 
 out:
 	spin_unlock(&br->multicast_lock);