linux-ext4 - Re: [PATCH v4 RESEND] ext4: Make sure BH_New bit is cleared in ->write

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <175296153003.397842.9984626191637719714.b4-ty@mit.edu>
Date: Sat, 19 Jul 2025 17:45:52 -0400
From: "Theodore Ts'o" <tytso@....edu>
To: Jan Kara <jack@...e.cz>
Cc: "Theodore Ts'o" <tytso@....edu>, linux-ext4@...r.kernel.org,
        Baolin Liu <liubaolin12138@....com>, Zhi Long <longzhi@...gfor.com.cn>
Subject: Re: [PATCH v4 RESEND] ext4: Make sure BH_New bit is cleared in ->write_end handler


On Wed, 09 Jul 2025 10:48:32 +0200, Jan Kara wrote:
> Currently we clear BH_New bit in case of error and also in the standard
> ext4_write_end() handler (in block_commit_write()). However
> ext4_journalled_write_end() misses this clearing and thus we are leaving
> stale BH_New bits behind. Generally ext4_block_write_begin() clears
> these bits before any harm can be done but in case blocksize < pagesize
> and we hit some error when processing a page with these stale bits,
> we'll try to zero buffers with these stale BH_New bits and jbd2 will
> complain (as buffers were not prepared for writing in this transaction).
> Fix the problem by clearing BH_New bits in ext4_journalled_write_end()
> and WARN if ext4_block_write_begin() sees stale BH_New bits.
> 
> [...]

Applied, thanks!

[1/1] ext4: Make sure BH_New bit is cleared in ->write_end handler
      commit: 91b8ca8b26729b729dda8a4eddb9aceaea706f37

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