linux-kernel - Re: [PATCH] sound: fix uninit-value in i2s_dma

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: <635f1691-74e9-4e48-8ebf-8e7ce0c6d1e3@sirena.org.uk>
Date: Wed, 30 Oct 2024 17:14:48 +0000
From: Mark Brown <broonie@...nel.org>
To: Suraj Sonawane <surajsonawane0215@...il.com>
Cc: Liam Girdwood <lgirdwood@...il.com>, Jaroslav Kysela <perex@...ex.cz>,
	Takashi Iwai <tiwai@...e.com>, linux-sound@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] sound: fix uninit-value in i2s_dma_isr

On Wed, Oct 30, 2024 at 10:38:29PM +0530, Suraj Sonawane wrote:
> Fix an issue detected by the Smatch tool:
> 
> sound/soc/bcm/bcm63xx-pcm-whistler.c:264 i2s_dma_isr()
> error: uninitialized symbol 'val_1'.
> sound/soc/bcm/bcm63xx-pcm-whistler.c:264 i2s_dma_isr()
> error: uninitialized symbol 'val_2'.
> 
> These errors occurred because the variables 'val_1' and 'val_2' are
> declared but may not be assigned a value before they are used.
> Specifically, if the loop that assigns values to 'val_1' and 'val_2'
> does not execute (for example, when 'offlevel' is zero), these
> variables remain uninitialized, leading to potential undefined
> behavior.
> 
> To resolve this issue, initialize 'val_1' and 'val_2' to 0 at the
> point of declaration. This ensures that 'val_1' and 'val_2' have
> defined values before they are used in subsequent calculations,
> preventing any warnings or undefined behavior in cases where the
> loop does not run.

This will shut the warning up, but why are these values valid?  Are we
handling the cases where the loops do not execute properly?

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)