[NET_SCHED]: Propagate nla_parse return value

nla_parse() returns more detailed errno codes, propagate them back on
error.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 6ce8da5..dcf6afc 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -207,10 +207,15 @@
 	struct nlattr *tb[TCA_RED_MAX + 1];
 	struct tc_red_qopt *ctl;
 	struct Qdisc *child = NULL;
+	int err;
 
-	if (opt == NULL || nla_parse_nested(tb, TCA_RED_MAX, opt, NULL))
+	if (opt == NULL)
 		return -EINVAL;
 
+	err = nla_parse_nested(tb, TCA_RED_MAX, opt, NULL);
+	if (err < 0)
+		return err;
+
 	if (tb[TCA_RED_PARMS] == NULL ||
 	    nla_len(tb[TCA_RED_PARMS]) < sizeof(*ctl) ||
 	    tb[TCA_RED_STAB] == NULL ||