Re: KASAN: use-after-free in ext4_find_extent in v6.9

From: Theodore Ts'o
Date: Thu May 16 2024 - 09:58:39 EST


On Wed, May 15, 2024 at 08:33:33PM -0400, Shuangpeng Bai wrote:
>
> You are right. I disabled CONFIG_BLK_DEV_WRITE_MOUNTED and found
> this bug can not be triggered anymore.
>
> I am wondering if there is any suggested way for me to check whether
> a bug is reproduced under a reasonable environment (such as
> compiling config) or not? If so, that would be very helpful.

As I mentioned, the upstream syzkaller always forces the
CONFIG_BLK_DEV_WRITE_MOUNTED to be disabled. That's the best way to
check whether the bug is reproducible under a reasonable environment,
and to do it in an automated way.

Cheers,

- Ted