Index: sys/netinet6/ip6_forward.c
===================================================================
--- sys/netinet6/ip6_forward.c
+++ sys/netinet6/ip6_forward.c
@@ -268,8 +268,9 @@
 			 * type/code is based on suggestion by Rich Draves.
 			 * not sure if it is the best pick.
 			 */
-			icmp6_error(mcopy, ICMP6_DST_UNREACH,
-				    ICMP6_DST_UNREACH_ADDR, 0);
+			if (mcopy)
+				icmp6_error(mcopy, ICMP6_DST_UNREACH,
+					    ICMP6_DST_UNREACH_ADDR, 0);
 			goto bad;
 		}
 		type = ND_REDIRECT;