Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.38 as permitted sender) client-ip=23.128.96.38;
Date:   Sat, 23 Sep 2023 19:53:41 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Justin Stitt <justinstitt@google.com>
Cc:     Lucas Stach <l.stach@pengutronix.de>,
        Russell King <linux+etnaviv@armlinux.org.uk>,
        Christian Gmeiner <christian.gmeiner@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>, etnaviv@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org, Bo YU <tsu.yubo@gmail.com>
Subject: Re: [PATCH v2] drm/etnaviv: refactor deprecated strncpy
Message-ID: <202309231952.6E01CF3589@keescook>
References: <20230918-strncpy-drivers-gpu-drm-etnaviv-etnaviv_perfmon-c-v2-1-8ae12071c138@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20230918-strncpy-drivers-gpu-drm-etnaviv-etnaviv_perfmon-c-v2-1-8ae12071c138@google.com>
Precedence: bulk

On Mon, Sep 18, 2023 at 01:34:08PM +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.
> 
> A suitable replacement is `strscpy_pad` due to the fact that it
> guarantees NUL-termination on the destination buffer whilst maintaining
> the NUL-padding behavior that strncpy provides.
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@vger.kernel.org
> Cc: Bo YU <tsu.yubo@gmail.com>
> Signed-off-by: Justin Stitt <justinstitt@google.com>

Looks good to me now. Thanks!

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

(Though again if you need a v3, making the Subject more specific would
be nice, "...: Replace strncpy with strscpy_pad"

-Kees

-- 
Kees Cook