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Message-ID: <e6384e25-dae3-4488-b1ca-e0c07a601741@linaro.org>
Date:   Mon, 9 Oct 2023 11:13:08 +0200
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From:   neil.armstrong@linaro.org
Reply-To: neil.armstrong@linaro.org
Subject: Re: [PATCH v2] drm/panel/panel-tpo-tpg110: fix a possible null
 pointer dereference
Content-Language: en-US, fr
To:     Ma Ke <make_ruc2021@163.com>, linus.walleij@linaro.org,
        sam@ravnborg.org, airlied@gmail.com, daniel@ffwll.ch
Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
References: <20231009090446.4043798-1-make_ruc2021@163.com>
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On 09/10/2023 11:04, Ma Ke wrote:
> In tpg110_get_modes(), the return value of drm_mode_duplicate() is
> assigned to mode, which will lead to a NULL pointer dereference on
> failure of drm_mode_duplicate(). Add a check to avoid npd.
> 
> Signed-off-by: Ma Ke <make_ruc2021@163.com>
> ---
>   drivers/gpu/drm/panel/panel-tpo-tpg110.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panel/panel-tpo-tpg110.c b/drivers/gpu/drm/panel/panel-tpo-tpg110.c
> index 845304435e23..f6a212e542cb 100644
> --- a/drivers/gpu/drm/panel/panel-tpo-tpg110.c
> +++ b/drivers/gpu/drm/panel/panel-tpo-tpg110.c
> @@ -379,6 +379,8 @@ static int tpg110_get_modes(struct drm_panel *panel,
>   	connector->display_info.bus_flags = tpg->panel_mode->bus_flags;
>   
>   	mode = drm_mode_duplicate(connector->dev, &tpg->panel_mode->mode);
> +	if (!mode)
> +		return -ENOMEM;
>   	drm_mode_set_name(mode);
>   	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
>   

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>