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Date:   Fri, 27 May 2022 11:21:44 -0400
From:   "Theodore Ts'o" <tytso@mit.edu>
To:     yebin <yebin10@huawei.com>
Cc:     Eric Whitney <enwlinux@gmail.com>, adilger.kernel@dilger.ca,
        linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
        jack@suse.cz
Subject: Re: [PATCH -next] ext4: Fix warning in ext4_da_release_space
Message-ID: <YpDsiCTi8sidvO7X@mit.edu>
References: <20220520025540.3189247-1-yebin10@huawei.com>
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 <62909593.2040809@huawei.com>
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On Fri, May 27, 2022 at 05:10:43PM +0800, yebin wrote:
> 
> Maybe  you can  run syzkaller with log as follows :

Oh, so this was something that was found using Syzkaller.  Was this
using the public syzkaller; if so, can you provide a link the
Syzkaller report?

If this was a from privately run syzkaller instance, was there a C
reproducer?  It appears that this was from a fuzzed instance, and it's
painful enoguh to extract the file system image from the C reproducer.
I have no idea how to extract the file system image from a Syzkaller
reproducer.

In any case, it sounds like this was triggered from a maliciously
corrupted / fuzzed image.  Can this warning be triggered from a
consistent file system, or does it require a corrupted extent tree?

	   		   	   	   - Ted