Re: [PATCH] ext4: Fix timer use-after-free on failed mount
From: Theodore Ts'o
Date: Tue Aug 27 2024 - 08:48:51 EST
On Sun, 14 Jul 2024 21:33:36 -0700, Xiaxi Shen wrote:
> Syzbot has found an ODEBUG bug in ext4_fill_super
>
> The del_timer_sync function cancels the s_err_report timer,
> which reminds about filesystem errors daily. We should
> guarantee the timer is no longer active before kfree(sbi).
>
> When filesystem mounting fails, the flow goes to failed_mount3,
> where an error occurs when ext4_stop_mmpd is called, causing
> a read I/O failure. This triggers the ext4_handle_error function
> that ultimately re-arms the timer,
> leaving the s_err_report timer active before kfree(sbi) is called.
>
> [...]
Applied, thanks!
[1/1] ext4: Fix timer use-after-free on failed mount
commit: 0ce160c5bdb67081a62293028dc85758a8efb22a
Best regards,
--
Theodore Ts'o <tytso@xxxxxxx>