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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Thu, 14 Mar 2024 10:38:33 +0100
Message-ID: <CAJfpegu8Rjj1cHkB6JD=TY1CWuVaH8YpSRLQe0cOfG9aQXj6Vw@mail.gmail.com>
Subject: Re: [syzbot] [overlayfs?] WARNING in ovl_copy_up_file
To: Amir Goldstein <amir73il@gmail.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, 
	linux-unionfs@vger.kernel.org, syzkaller-bugs@googlegroups.com, 
	syzbot <syzbot+3abd99031b42acf367ef@syzkaller.appspotmail.com>
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On Wed, 13 Mar 2024 at 21:55, Amir Goldstein <amir73il@gmail.com> wrote:

> The WARN_ON that I put in ovl_verify_area() may be too harsh.
> I think they can happen if lower file is changed (i_size) while file is being
> copied up after reading i_size into the copy length and this could be
> the case with this syzbot reproducer that keeps mounting overlayfs
> instances over same path.
>
> Should probably demote those WARN_ON to just returning EIO?

Sounds good.

Thanks,
Miklos