Re: [syzbot] KASAN: use-after-free Read in ext4_xattr_set_entry (4)

From: Dmitry Vyukov
Date: Fri Mar 25 2022 - 02:19:13 EST


On Wed, 23 Mar 2022 at 16:07, syzbot
<syzbot+4cb1e27475bf90a9b926@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> syzbot suspects this issue was fixed by commit:
>
> commit 6e47a3cc68fc525428297a00524833361ebbb0e9
> Author: Lukas Czerner <lczerner@xxxxxxxxxx>
> Date: Wed Oct 27 14:18:52 2021 +0000
>
> ext4: get rid of super block and sbi from handle_mount_ops()
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=100bc10b700000
> start commit: f8ad8187c3b5 fs/pipe: allow sendfile() to pipe again
> git tree: upstream
> kernel config: https://syzkaller.appspot.com/x/.config?x=96b123631a6700e9
> dashboard link: https://syzkaller.appspot.com/bug?extid=4cb1e27475bf90a9b926
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11131f94d00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c3761b500000
>
> If the result looks correct, please mark the issue as fixed by replying with:
>
> #syz fix: ext4: get rid of super block and sbi from handle_mount_ops()
>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection

Looks reasonable:

#syz fix: ext4: get rid of super block and sbi from handle_mount_ops()