Re: possible deadlock (4)

From: Dmitry Vyukov
Date: Mon Jan 15 2018 - 03:48:48 EST


On Mon, Jan 15, 2018 at 9:46 AM, syzbot
<syzbot+a9b2d0e21403c12cb074@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> Hello,
>
> syzkaller hit the following crash on
> 2c1cfa49901839136e578ca516a7e230182da024
> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> compiler: gcc (GCC) 7.1.1 20170620
> .config is attached
> Raw console output is attached.
> C reproducer is attached
> syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> for information about syzkaller reproducers
>
>
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#syz dup: possible deadlock in shmem_file_llseek

+ashmem maintainers

> audit: type=1400 audit(1515952945.475:8): avc: denied { map } for
> pid=3656 comm="syzkaller443286" path="/dev/ashmem" dev="devtmpfs" ino=8948
> scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
> tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1
>
> ======================================================
> WARNING: possible circular locking dependency detected
> 4.15.0-rc7+ #261 Not tainted
> ----------------------------------------------
>
>
> ---
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