Re: [PATCH] drm/imx: imx-ldb: Check for null pointer after calling kmemdup

From: Philipp Zabel <p.zabel@pengutronix.de>
To: Jiasheng Jiang <jiasheng@iscas.ac.cn>,
	airlied@linux.ie, daniel@ffwll.ch, shawnguo@kernel.org,
	s.hauer@pengutronix.de, kernel@pengutronix.de,
	festevam@gmail.com, linux-imx@nxp.com
Cc: dri-devel@lists.freedesktop.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] drm/imx: imx-ldb: Check for null pointer after calling kmemdup
Date: Tue, 29 Mar 2022 18:41:11 +0200	[thread overview]
Message-ID: <f8babd522487dd8e9955019a4141ce78ffca2087.camel@pengutronix.de> (raw)
In-Reply-To: <20220105074729.2363657-1-jiasheng@iscas.ac.cn>

On Mi, 2022-01-05 at 15:47 +0800, Jiasheng Jiang wrote:
> As the possible failure of the allocation, kmemdup() may return NULL
> pointer.
> Therefore, it should be better to check the return value of kmemdup()
> and return error if fails.
> 
> Fixes: dc80d7038883 ("drm/imx-ldb: Add support to drm-bridge")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/gpu/drm/imx/imx-ldb.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-
> ldb.c
> index 53132ddf9587..f9880a779678 100644
> --- a/drivers/gpu/drm/imx/imx-ldb.c
> +++ b/drivers/gpu/drm/imx/imx-ldb.c
> @@ -574,6 +574,8 @@ static int imx_ldb_panel_ddc(struct device *dev,
>                 edidp = of_get_property(child, "edid", &edid_len);
>                 if (edidp) {
>                         channel->edid = kmemdup(edidp, edid_len,
> GFP_KERNEL);
> +                       if (!channel->edid)
> +                               return -ENOMEM;
>                 } else if (!channel->panel) {
>                         /* fallback to display-timings node */
>                         ret = of_get_drm_display_mode(child,

Thank you, applied to imx-drm/fixes.

regards
Philipp