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From:   "Theodore Ts'o" <tytso@mit.edu>
To:     linux-ext4@vger.kernel.org, Lukas Czerner <lczerner@redhat.com>
Cc:     "Theodore Ts'o" <tytso@mit.edu>, stable@vger.kernel.org
Subject: Re: [PATCH 1/2] ext4: check if directory block is within i_size
Date:   Fri, 22 Jul 2022 09:58:16 -0400
Message-Id: <165849767595.303416.1808968339954270899.b4-ty@mit.edu>
In-Reply-To: <20220704142721.157985-1-lczerner@redhat.com>
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On Mon, 4 Jul 2022 16:27:20 +0200, Lukas Czerner wrote:
> Currently ext4 directory handling code implicitly assumes that the
> directory blocks are always within the i_size. In fact ext4_append()
> will attempt to allocate next directory block based solely on i_size and
> the i_size is then appropriately increased after a successful
> allocation.
> 
> However, for this to work it requires i_size to be correct. If, for any
> reason, the directory inode i_size is corrupted in a way that the
> directory tree refers to a valid directory block past i_size, we could
> end up corrupting parts of the directory tree structure by overwriting
> already used directory blocks when modifying the directory.
> 
> [...]

Applied, thanks!

[1/2] ext4: check if directory block is within i_size
      commit: 65d23bd6e76ae07cee50c24d1fbeea4044aa41e7
[2/2] ext4: make sure ext4_append() always allocates new block
      commit: 6d3ab9450ea5ec08882ab2f255827f1a39e300de

Best regards,
-- 
Theodore Ts'o <tytso@mit.edu>