Re: [syzbot] KASAN: use-after-free Read in exit_mmap

[Liam Howlett]

* syzbot <syzbot+99551d8b4d180f6cb1c0@xxxxxxxxxxxxxxxxxxxxxxxxx> [220727 14:02]:
> syzbot has bisected this issue to:
> 
> commit e23cb70bcbef5c189790042d1d6d89e33308c386
> Author: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> Date:   Tue Jun 21 20:47:14 2022 +0000
> 
>     mm: remove the vma linked list
> 
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1078f202080000
> start commit:   cb71b93c2dc3 Add linux-next specific files for 20220628
> git tree:       linux-next
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=1278f202080000
> console output: https://syzkaller.appspot.com/x/log.txt?x=1478f202080000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=badbc1adb2d582eb
> dashboard link: https://syzkaller.appspot.com/bug?extid=99551d8b4d180f6cb1c0
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=117dc816080000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12695b26080000
> 
> Reported-by: syzbot+99551d8b4d180f6cb1c0@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: e23cb70bcbef ("mm: remove the vma linked list")
> 
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection

Thanks.  I tested this against the most recent patches with the above
kernel config and the issue has already been resolved.