diff --git a/sys/netinet6/in6_rmx.c b/sys/netinet6/in6_rmx.c
index 7e1a2620a0bc..bb5434186f83 100644
--- a/sys/netinet6/in6_rmx.c
+++ b/sys/netinet6/in6_rmx.c
@@ -160,7 +160,7 @@ in6_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
 		 * Find out if it is because of an
 		 * ARP entry and delete it if so.
 		 */
-		rt2 = rtalloc1((struct sockaddr *)sin6, 0, RTF_CLONING);
+		rt2 = rtalloc1((struct sockaddr *)sin6, 0, RTF_RNH_LOCKED|RTF_CLONING);
 		if (rt2) {
 			if (rt2->rt_flags & RTF_LLINFO &&
 				rt2->rt_flags & RTF_HOST &&
@@ -187,7 +187,7 @@ in6_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
 		 *	net route entry, 3ffe:0501:: -> if0.
 		 *	This case should not raise an error.
 		 */
-		rt2 = rtalloc1((struct sockaddr *)sin6, 0, RTF_CLONING);
+		rt2 = rtalloc1((struct sockaddr *)sin6, 0, RTF_RNH_LOCKED|RTF_CLONING);
 		if (rt2) {
 			if ((rt2->rt_flags & (RTF_CLONING|RTF_HOST|RTF_GATEWAY))
 					== RTF_CLONING