commit 3ef0952ca85e28226b09a6d833c30e3e604a63c8
author Andrew Lunn <andrew@lunn.ch> Thu Dec 03 21:12:32 2015 +0100
committer David S. Miller <davem@davemloft.net> Sat Dec 05 17:41:42 2015 -0500
tree 736c5ecb91f789a268c0ef3404c8c9d8c6476245
parent 2f8364a291e8adde25c93f97a76abbcaf4b1ed3f

ipv6: Only act upon NETDEV_*_TYPE_CHANGE if we have ipv6 addresses

An interface changing type may not have IPv6 addresses. Don't
call the address configuration type change in this case.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 6936d0d..5e9111d 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3287,7 +3287,8 @@
 
 	case NETDEV_PRE_TYPE_CHANGE:
 	case NETDEV_POST_TYPE_CHANGE:
-		addrconf_type_change(dev, event);
+		if (idev)
+			addrconf_type_change(dev, event);
 		break;
 	}