diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index c1acf69858fd..99e6e4bb1c72 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2690,6 +2690,12 @@ static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
 {
 }
 
+static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
+					  unsigned long old)
+{
+	return NULL;
+}
+
 static struct dst_ops ipv4_dst_blackhole_ops = {
 	.family			=	AF_INET,
 	.protocol		=	cpu_to_be16(ETH_P_IP),
@@ -2698,6 +2704,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
 	.default_mtu		=	ipv4_blackhole_default_mtu,
 	.default_advmss		=	ipv4_default_advmss,
 	.update_pmtu		=	ipv4_rt_blackhole_update_pmtu,
+	.cow_metrics		=	ipv4_rt_blackhole_cow_metrics,
 };
 
 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 0a5d02ae5ceb..fd0eec6f88c6 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -153,6 +153,12 @@ static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
 {
 }
 
+static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
+					 unsigned long old)
+{
+	return NULL;
+}
+
 static struct dst_ops ip6_dst_blackhole_ops = {
 	.family			=	AF_INET6,
 	.protocol		=	cpu_to_be16(ETH_P_IPV6),
@@ -161,6 +167,7 @@ static struct dst_ops ip6_dst_blackhole_ops = {
 	.default_mtu		=	ip6_blackhole_default_mtu,
 	.default_advmss		=	ip6_default_advmss,
 	.update_pmtu		=	ip6_rt_blackhole_update_pmtu,
+	.cow_metrics		=	ip6_rt_blackhole_cow_metrics,
 };
 
 static const u32 ip6_template_metrics[RTAX_MAX] = {