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Date:   Sat, 23 Sep 2023 20:01:41 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Justin Stitt <justinstitt@google.com>
Cc:     Patrik Jakobsson <patrik.r.jakobsson@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2] drm/gma500: refactor deprecated strncpy
Message-ID: <202309232000.E307B49B@keescook>
References: <20230919-drivers-gpu-drm-gma500-oaktrail_lvds_i2c-c-v2-1-9ebe6983b4cb@google.com>
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On Tue, Sep 19, 2023 at 04:41:16AM +0000, Justin Stitt wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings [1].
> 
> We should prefer more robust and less ambiguous string interfaces.
> 
> Since `chan->base.name` is expected to be NUL-terminated, a suitable
> replacement is `strscpy` [2] due to the fact that it guarantees
> NUL-termination on the destination buffer without also unnecessarily
> NUL-padding (since `chan` is kzalloc'd already).
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@vger.kernel.org
> Signed-off-by: Justin Stitt <justinstitt@google.com>

Thanks, looks good. If a v3 is needed, Subject can be improved to be
"...: Replace strncpy with strscpy".

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook