[ 24/38] IPv6: Fix not join all-router mcast group when forwarding set.

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

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


From: Li Wei <redacted>

[ Upstream commit d6ddef9e641d1229d4ec841dc75ae703171c3e92 ]

When forwarding was set and a new net device is register,
we need add this device to the all-router mcast group.

Signed-off-by: Li Wei <redacted>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv6/addrconf.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c

@@ -433,6 +433,10 @@ static struct inet6_dev * ipv6_add_dev(s
 	/* Join all-node multicast group */
 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
 
+	/* Join all-router multicast group if forwarding is set */
+	if (ndev->cnf.forwarding && dev && (dev->flags & IFF_MULTICAST))
+		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
+
 	return ndev;
 }