[v1] drm/panel/panel-tpo-tpg110: fix a possible null pointer dereference

[PATCH] drm/panel/panel-tpo-tpg110: fix a possible null pointer dereference

Posted by Ma Ke 2 years, 2 months ago

In radeon_fp_native_mode(), 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;
 
-- 
2.37.2

Re: [PATCH] drm/panel/panel-tpo-tpg110: fix a possible null pointer dereference

Posted by neil.armstrong@linaro.org 2 years, 2 months ago

On 07/10/2023 05:03, Ma Ke wrote:
> In radeon_fp_native_mode(), the return value of drm_mode_duplicate()

Wrong function, it should be tpg110_get_modes()

Thanks,
Neil

> 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;
>