diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 58642b29a499..9bd30fd4de4b 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2769,10 +2769,12 @@ struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
 	if (IS_ERR(rt))
 		return rt;
 
-	if (flp4->flowi4_proto)
+	if (flp4->flowi4_proto) {
+		flp4->flowi4_oif = rt->dst.dev->ifindex;
 		rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst,
 							flowi4_to_flowi(flp4),
 							sk, 0);
+	}
 
 	return rt;
 }