Forwarded: Re: [syzbot] [bcachefs] KASAN: use-after-free Read in crypto_poly1305_update

From: syzbot
Date: Thu Jul 17 2025 - 17:46:06 EST


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Subject: Re: [syzbot] [bcachefs] KASAN: use-after-free Read in crypto_poly1305_update
Author: kent.overstreet@xxxxxxxxx

On Thu, Jul 17, 2025 at 01:49:03PM -0700, syzbot wrote:
> syzbot suspects this issue was fixed by commit:
>
> commit d89a34b14df5c205de698c23c3950b2b947cdb97
> Author: Alan Huang <mmpgouride@xxxxxxxxx>
> Date: Sat Jun 14 09:18:07 2025 +0000
>
> bcachefs: Move bset size check before csum check
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1722a58c580000
> start commit: 2408a807bfc3 Merge tag 'vfs-6.14-rc4.fixes' of git://git.k..
> git tree: upstream
> kernel config: https://syzkaller.appspot.com/x/.config?x=6cc40dfe827ffb85
> dashboard link: https://syzkaller.appspot.com/bug?extid=d587b24799bd8c2d32f4
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12c4f2e4580000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17e4c498580000
>
> If the result looks correct, please mark the issue as fixed by replying with:
>
#syz fix: bcachefs: Move bset size check before csum check