From:   Jani Nikula <jani.nikula@linux.intel.com>
To:     Johan Hovold <johan+linaro@kernel.org>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>
Cc:     Douglas Anderson <dianders@chromium.org>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        dri-devel@lists.freedesktop.org,
        Johan Hovold <johan+linaro@kernel.org>
Subject: Re: [PATCH] drm/edid: fix info leak when failing to get panel id
In-Reply-To: <20230302074704.11371-1-johan+linaro@kernel.org>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
References: <20230302074704.11371-1-johan+linaro@kernel.org>
Date:   Thu, 02 Mar 2023 10:17:30 +0200
Message-ID: <874jr3worp.fsf@intel.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

On Thu, 02 Mar 2023, Johan Hovold <johan+linaro@kernel.org> wrote:
> Make sure to clear the transfer buffer before fetching the EDID to
> avoid leaking slab data to the logs on errors that leave the buffer
> unchanged.
>
> Fixes: 69c7717c20cc ("drm/edid: Dump the EDID when drm_edid_get_panel_id() has an error")
> Cc: stable@vger.kernel.org	# 6.2
> Cc: Douglas Anderson <dianders@chromium.org>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

> ---
>  drivers/gpu/drm/drm_edid.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index 3841aba17abd..8707fe72a028 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -2797,7 +2797,7 @@ u32 drm_edid_get_panel_id(struct i2c_adapter *adapter)
>  	 * the EDID then we'll just return 0.
>  	 */
>  
> -	base_block = kmalloc(EDID_LENGTH, GFP_KERNEL);
> +	base_block = kzalloc(EDID_LENGTH, GFP_KERNEL);
>  	if (!base_block)
>  		return 0;

-- 
Jani Nikula, Intel Open Source Graphics Center