Commit 3179dd79 authored Aug 30, 2021 by Haimin Zhang Committed by Greg Kroah-Hartman Sep 22, 2021

fix array-index-out-of-bounds in taprio_change



[ 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@syzkaller.appspotmail.com>
Signed-off-by: Haimin Zhang <tcs_kernel@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent ef9a7867

net/sched/sch_taprio.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -1503,7 +1503,9 @@ 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],