linux-kernel - Re: [PATCH] drm/i2c: tda998x: Remove VLA usage

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Message-ID: <20180409222141.GR16141@n2100.armlinux.org.uk>
Date:   Mon, 9 Apr 2018 23:21:41 +0100
From:   Russell King - ARM Linux <linux@...linux.org.uk>
To:     Laura Abbott <labbott@...hat.com>
Cc:     David Airlie <airlied@...ux.ie>, dri-devel@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org, kernel-hardening@...ts.openwall.com,
        Kees Cook <keescook@...omium.org>
Subject: Re: [PATCH] drm/i2c: tda998x: Remove VLA usage

On Mon, Apr 09, 2018 at 02:07:03PM -0700, Laura Abbott wrote:
> There's an ongoing effort to remove VLAs[1] from the kernel to eventually
> turn on -Wvla. The vla in reg_write_range is based on the length of data
> passed. The one use of a non-constant size for this range is bounded by
> the size buffer passed to hdmi_infoframe_pack which is a fixed size.
> Switch to this upper bound.

Does this _really_ make it safer?  What if the code is modified to write
more than 32 bytes in the future?

Sorry, I don't think this is safer at all.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
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