Re: WARNING: lock held when returning to user space! (3)

From: Dmitry Vyukov
Date: Wed Jan 02 2019 - 06:24:22 EST


On Wed, Jan 2, 2019 at 11:59 AM syzbot
<syzbot+42e36e1ae3de3f22a7ed@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: 903b77c63167 Merge tag 'linux-kselftest-4.21-rc1' of git:/..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1424673b400000
> kernel config: https://syzkaller.appspot.com/x/.config?x=53a2f2aa0b1f7606
> dashboard link: https://syzkaller.appspot.com/bug?extid=42e36e1ae3de3f22a7ed
> compiler: gcc (GCC) 8.0.1 20180413 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1453eabf400000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14a492bf400000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+42e36e1ae3de3f22a7ed@xxxxxxxxxxxxxxxxxxxxxxxxx

#syz dup: WARNING: lock held when returning to user space in set_property_atomic

> RBP: 00000000006cf018 R08: 0000000000000001 R09: 0000000000000032
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
> R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000
>
> ================================================
> WARNING: lock held when returning to user space!
> 4.20.0+ #395 Not tainted
> ------------------------------------------------
> syz-executor520/8085 is leaving the kernel with locks still held!
>
>
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxxx
>
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>
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