Re: [PATCH V2] fix array-index-out-of-bounds in taprio_change

On Mon, Aug 30, 2021 at 10:14 AM Jakub Kicinski [off-list ref] wrote:

On Mon, 30 Aug 2021 11:30:06 +0000 patchwork-bot+netdevbpf@kernel.org
wrote:

quoted

Hello:

This patch was applied to netdev/net-next.git (refs/heads/master):

On Mon, 30 Aug 2021 11:47:01 +0800 you wrote:

quoted

From: Haimin Zhang <redacted>

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.

[...]

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!

https://lore.kernel.org/netdev/20210830091046.610ceb1b@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com/ (local)

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.

Thanks.