linux-kernel - Re: [PATCH 1/9] block: fix data loss and stale date exposure problems during append 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] [thread-next>] [day] [month] [year] [list]

Message-ID: <aSk5QFHzCwz97Xqw@infradead.org>
Date: Thu, 27 Nov 2025 21:55:12 -0800
From: Christoph Hellwig <hch@...radead.org>
To: Stephen Zhang <starzhangzsd@...il.com>
Cc: Andreas Gruenbacher <agruenba@...hat.com>,
	Christoph Hellwig <hch@...radead.org>, linux-kernel@...r.kernel.org,
	linux-block@...r.kernel.org, nvdimm@...ts.linux.dev,
	virtualization@...ts.linux.dev, linux-nvme@...ts.infradead.org,
	gfs2@...ts.linux.dev, ntfs3@...ts.linux.dev,
	linux-xfs@...r.kernel.org, zhangshida@...inos.cn
Subject: Re: [PATCH 1/9] block: fix data loss and stale date exposure
 problems during append write

On Fri, Nov 28, 2025 at 11:22:49AM +0800, Stephen Zhang wrote:
> Therefore, we could potentially change it to::
> 
>         if (bio->bi_status && !READ_ONCE(parent->bi_status))
>                 parent->bi_status = bio->bi_status;
> 
> But as you mentioned, the check might not be critical here. So ultimately,
> we can simplify it to:
> 
>         if (bio->bi_status)
>                 parent->bi_status = bio->bi_status;

It might make sense to just use cmpxchg.  See btrfs_bio_end_io as an
example (although it is operating on the btrfs_bio structure)