Re: KASAN: use-after-free Read in sctp_sock_dump

From: Marcelo Ricardo Leitner
Date: Mon Oct 28 2019 - 11:36:55 EST


On Mon, Oct 28, 2019 at 08:32:08AM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: d6d5df1d Linux 5.4-rc5
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=17ef5a70e00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=2bcb64e504d04eff
> dashboard link: https://syzkaller.appspot.com/bug?extid=e5b57b8780297657b25b
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> userspace arch: i386
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16cd8800e00000
>
> The bug was bisected to:
>
> commit 61086f391044fd587af9d70a9b8f6f800dd474ba
> Author: Vlad Buslov <vladbu@xxxxxxxxxxxx>
> Date: Fri Aug 2 19:21:56 2019 +0000
>
> net/mlx5e: Protect encap hash table with mutex
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=135960af600000

This is weird. This mlx5e commit has nothing to do with SCTP diag
dump.

Marcelo