From: Haimin Zhang <tcs_kernel@xxxxxxxxxxx> [ Upstream commit efe487fce3061d94222c6501d7be3aa549b3dc78 ] syzbot report an array-index-out-of-bounds in taprio_change index 16 is out of range for type '__u16 [16]' that's because mqprio->num_tc is lager than TC_MAX_QUEUE,so we check the return value of netdev_set_num_tc. Reported-by: syzbot+2b3e5fb6c7ef285a94f6@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Haimin Zhang <tcs_kernel@xxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/sched/sch_taprio.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 00853065dfa0..cb5e5220da55 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1502,7 +1502,9 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, taprio_set_picos_per_byte(dev, q); if (mqprio) { - netdev_set_num_tc(dev, mqprio->num_tc); + err = netdev_set_num_tc(dev, mqprio->num_tc); + if (err) + goto free_sched; for (i = 0; i < mqprio->num_tc; i++) netdev_set_tc_queue(dev, i, mqprio->count[i], -- 2.30.2