Re: [syzbot] WARNING in futex_requeue

From: Thomas Gleixner
Date: Wed Sep 01 2021 - 15:52:30 EST


On Wed, Sep 01 2021 at 06:26, syzbot wrote:
> syzbot found the following issue on:
>
> HEAD commit: b91db6a0b52e Merge tag 'for-5.15/io_uring-vfs-2021-08-30' ..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=17907235300000
> kernel config: https://syzkaller.appspot.com/x/.config?x=961d30359ac81f8c
> dashboard link: https://syzkaller.appspot.com/bug?extid=4d1bd0725ef09168e1a0
> compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1222185d300000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+4d1bd0725ef09168e1a0@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> ------------[ cut here ]------------
> WARNING: CPU: 1 PID: 5701 at kernel/futex.c:2259 futex_requeue+0x1467/0x2d50 kernel/futex.c:2259

Doh. That Gleixner dude did not think this through completely. Fix will
follow.

Thanks,

tglx