Re: KASAN: null-ptr-deref Write in kthread_use_mm

From: Jens Axboe
Date: Mon Nov 02 2020 - 10:19:34 EST


On 11/2/20 4:54 AM, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 4e78c578 Add linux-next specific files for 20201030
> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=148969d4500000
> kernel config: https://syzkaller.appspot.com/x/.config?x=83318758268dc331
> dashboard link: https://syzkaller.appspot.com/bug?extid=b57abf7ee60829090495
> compiler: gcc (GCC) 10.1.0-syz 20200507
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17e1346c500000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1388fbca500000
>
> The issue was bisected to:
>
> commit 4d004099a668c41522242aa146a38cc4eb59cb1e
> Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Date: Fri Oct 2 09:04:21 2020 +0000
>
> lockdep: Fix lockdep recursion

That bisection definitely isn't correct. But I'll take a look at the issue.

--
Jens Axboe