diff --git a/sys/contrib/ipfilter/netinet/fil.c b/sys/contrib/ipfilter/netinet/fil.c
index 91a7f9069b91..ffb5611e2de5 100644
--- a/sys/contrib/ipfilter/netinet/fil.c
+++ b/sys/contrib/ipfilter/netinet/fil.c
@@ -1299,6 +1299,7 @@ ipf_pr_icmp(fin)
 			}
 		}
 #endif
+		/* fallthrough is intentional */
 	case ICMP_SOURCEQUENCH :
 	case ICMP_REDIRECT :
 	case ICMP_TIMXCEED :