diff --git a/sys/net/altq/altq_rmclass.c b/sys/net/altq/altq_rmclass.c
--- a/sys/net/altq/altq_rmclass.c
+++ b/sys/net/altq/altq_rmclass.c
@@ -677,6 +677,8 @@
 	mtu = ifq->altq_ifp->if_mtu;
 	ifd->ifq_ = ifq;
 	ifd->restart = restart;
+	if (maxqueued <= 0 || maxqueued > RM_MAXQUEUED)
+		maxqueued = RM_MAXQUEUED;
 	ifd->maxqueued_ = maxqueued;
 	ifd->ns_per_byte_ = nsecPerByte;
 	ifd->maxpkt_ = mtu;