Re: [PATCH V2] fix array-index-out-of-bounds in taprio_change
From: Cong Wang
Date: Tue Aug 31 2021 - 01:56:37 EST
On Mon, Aug 30, 2021 at 10:14 AM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
> On Mon, 30 Aug 2021 11:30:06 +0000 patchwork-bot+netdevbpf@xxxxxxxxxx
> > Hello:
> > This patch was applied to netdev/net-next.git (refs/heads/master):
> > On Mon, 30 Aug 2021 11:47:01 +0800 you wrote:
> > > From: Haimin Zhang <tcs_kernel@xxxxxxxxxxx>
> > >
> > > syzbot report an array-index-out-of-bounds in taprio_change
> > > index 16 is out of range for type '__u16 '
> > > that's because mqprio->num_tc is lager than TC_MAX_QUEUE,so we check
> > > the return value of netdev_set_num_tc.
> > >
> > > [...]
> > Here is the summary with links:
> > - [V2] fix array-index-out-of-bounds in taprio_change
> > https://git.kernel.org/netdev/net-next/c/efe487fce306
> > You are awesome, thank you!
> Oh, well...
I agree it is slightly better to make the check work in
taprio_parse_mqprio_opt(), but this patch is not bad either, we
need to check the return value of netdev_set_num_tc() for
completeness at least.
BTW, this patch should be landed in -net, not -net-next, as it
fixes a real bug reported by syzbot.