Re: [syzbot] [io-uring?] KASAN: use-after-free Read in io_worker_get

From: Aleksandr Nogikh
Date: Wed Mar 15 2023 - 08:17:54 EST


Looks reasonable

#syz fix: io_uring/io-wq: only free worker if it was allocated for creation


On Wed, Mar 15, 2023 at 6:35 AM syzbot
<syzbot+55cc59267340fad29512@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> syzbot suspects this issue was fixed by commit:
>
> commit e6db6f9398dadcbc06318a133d4c44a2d3844e61
> Author: Jens Axboe <axboe@xxxxxxxxx>
> Date: Sun Jan 8 17:39:17 2023 +0000
>
> io_uring/io-wq: only free worker if it was allocated for creation
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=108bc2e2c80000
> start commit: a689b938df39 Merge tag 'block-2023-01-06' of git://git.ker..
> git tree: upstream
> kernel config: https://syzkaller.appspot.com/x/.config?x=33ad6720950f996d
> dashboard link: https://syzkaller.appspot.com/bug?extid=55cc59267340fad29512
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1532ef72480000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10b43f3a480000
>
> If the result looks correct, please mark the issue as fixed by replying with:
>
> #syz fix: io_uring/io-wq: only free worker if it was allocated for creation
>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>