Re: [syzbot] [kernel?] possible deadlock in exit_itimers

From: Thomas Gleixner
Date: Sun Jun 18 2023 - 16:50:04 EST


On Fri, Jun 16 2023 at 22:14, syzbot wrote:
> syzbot has bisected this issue to:
>
> commit 1b59b2577582f9cf3d0f17245675a76859175cc1
> Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Date: Thu Jun 1 20:16:34 2023 +0000
>
> posix-timers: Prevent RT livelock in itimer_delete()
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=106d46e3280000
> start commit: f7efed9f38f8 Add linux-next specific files for 20230616
> git tree: linux-next
> final oops: https://syzkaller.appspot.com/x/report.txt?x=126d46e3280000
> console output: https://syzkaller.appspot.com/x/log.txt?x=146d46e3280000
> kernel config: https://syzkaller.appspot.com/x/.config?x=60b1a32485a77c16
> dashboard link: https://syzkaller.appspot.com/bug?extid=5fd924f4cd9dc1c7828c
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1401d8ef280000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=176b45cf280000
>
> Reported-by: syzbot+5fd924f4cd9dc1c7828c@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: 1b59b2577582 ("posix-timers: Prevent RT livelock in itimer_delete()")

I've amended the original commit as that is tagged stable.

Thanks for chatching this and reporting!

tglx