net: Add dummy dst_ops->redirect method where needed.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index e98207dc..23bbe29 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2591,6 +2591,10 @@
 {
 }
 
+static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sk_buff *skb)
+{
+}
+
 static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
 					  unsigned long old)
 {
@@ -2605,6 +2609,7 @@
 	.mtu			=	ipv4_blackhole_mtu,
 	.default_advmss		=	ipv4_default_advmss,
 	.update_pmtu		=	ipv4_rt_blackhole_update_pmtu,
+	.redirect		=	ipv4_rt_blackhole_redirect,
 	.cow_metrics		=	ipv4_rt_blackhole_cow_metrics,
 	.neigh_lookup		=	ipv4_neigh_lookup,
 };