diff --git a/sys/netinet/in_mcast.c b/sys/netinet/in_mcast.c
index f93c4b0dac8..3dc4fa27168 100644
--- a/sys/netinet/in_mcast.c
+++ b/sys/netinet/in_mcast.c
@@ -1181,6 +1181,7 @@ inm_purge(struct in_multi *inm)
 		free(ims, M_IPMSOURCE);
 		inm->inm_nsrc--;
 	}
+	mbufq_drain(&inm->inm_scq);
 }
 
 /*