3.1-stable review patch.  If anyone has any objections, please let me know.

------------------


From: Thomas Graf <redacted>

[ Upstream commit 7838f2ce36b6ab5c13ef20b1857e3bbd567f1759 ]

Userspace may not provide TCA_OPTIONS, in fact tc currently does
so not do so if no arguments are specified on the command line.
Return EINVAL instead of panicing.

Signed-off-by: Thomas Graf <redacted>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 net/sched/sch_mqprio.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/sched/sch_mqprio.c
+++ b/net/sched/sch_mqprio.c

@@ -106,7 +106,7 @@ static int mqprio_init(struct Qdisc *sch
 	if (!netif_is_multiqueue(dev))
 		return -EOPNOTSUPP;
 
-	if (nla_len(opt) < sizeof(*qopt))
+	if (!opt || nla_len(opt) < sizeof(*qopt))
 		return -EINVAL;
 
 	qopt = nla_data(opt);