--- sch_dsmark.c	2004/04/11 19:39:16	1.1
+++ sch_dsmark.c	2004/04/11 19:39:41
@@ -321,6 +321,7 @@
 	struct rtattr *tb[TCA_DSMARK_MAX];
 	__u16 tmp;
 
+	if (!opt) return -EINVAL;
 	DPRINTK("dsmark_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
 	if (rtattr_parse(tb,TCA_DSMARK_MAX,RTA_DATA(opt),RTA_PAYLOAD(opt)) < 0 ||
 	    !tb[TCA_DSMARK_INDICES-1] ||