linux-kernel - Re: [PATCH v2 1/2] string: add mem_is_zero() helper to check if memory area is all zeros

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: <202408150906.28A920F62@keescook>
Date: Thu, 15 Aug 2024 09:07:01 -0700
From: Kees Cook <kees@...nel.org>
To: Jani Nikula <jani.nikula@...el.com>
Cc: linux-kernel@...r.kernel.org, dri-devel@...ts.freedesktop.org,
	intel-gfx@...ts.freedesktop.org, Andy Shevchenko <andy@...nel.org>
Subject: Re: [PATCH v2 1/2] string: add mem_is_zero() helper to check if
 memory area is all zeros

On Wed, Aug 14, 2024 at 01:00:34PM +0300, Jani Nikula wrote:
> Almost two thirds of the memchr_inv() usages check if the memory area is
> all zeros, with no interest in where in the buffer the first non-zero
> byte is located. Checking for !memchr_inv(s, 0, n) is also not very
> intuitive or discoverable. Add an explicit mem_is_zero() helper for this
> use case.
> 
> Signed-off-by: Jani Nikula <jani.nikula@...el.com>

Reviewed-by: Kees Cook <kees@...nel.org>

-- 
Kees Cook