[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/cls_route.c b/net/sched/cls_route.c
index b1aae84..3aa8109 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -440,8 +440,9 @@
 	if (opt == NULL)
 		return handle ? -EINVAL : 0;
 
-	if (nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, NULL) < 0)
-		return -EINVAL;
+	err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, NULL);
+	if (err < 0)
+		return err;
 
 	if ((f = (struct route4_filter*)*arg) != NULL) {
 		if (f->handle != handle && handle)