[v1] drm: i915: fix a possible refcount leak in intel_dp_add_mst_connector()

[PATCH] drm: i915: fix a possible refcount leak in intel_dp_add_mst_connector()

Posted by Hangyu Hua 3 years, 11 months ago

If drm_connector_init fails, intel_connector_free will be called to take 
care of proper free. So it is necessary to drop the refcount of port 
before intel_connector_free.

Fixes: 091a4f91942a ("drm/i915: Handle drm-layer errors in intel_dp_add_mst_connector")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---
 drivers/gpu/drm/i915/display/intel_dp_mst.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index e30e698aa684..f7d46ea3afb9 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -841,6 +841,7 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
 	ret = drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs,
 				 DRM_MODE_CONNECTOR_DisplayPort);
 	if (ret) {
+		drm_dp_mst_put_port_malloc(port);
 		intel_connector_free(intel_connector);
 		return NULL;
 	}
-- 
2.25.1

Re: [PATCH] drm: i915: fix a possible refcount leak in intel_dp_add_mst_connector()

Posted by Souza, Jose 3 years, 10 months ago

On Mon, 2022-05-16 at 15:19 +0800, Hangyu Hua wrote:
> If drm_connector_init fails, intel_connector_free will be called to take 
> care of proper free. So it is necessary to drop the refcount of port 
> before intel_connector_free.

Reviewed-by: José Roberto de Souza <jose.souza@intel.com>

> 
> Fixes: 091a4f91942a ("drm/i915: Handle drm-layer errors in intel_dp_add_mst_connector")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index e30e698aa684..f7d46ea3afb9 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -841,6 +841,7 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
>  	ret = drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs,
>  				 DRM_MODE_CONNECTOR_DisplayPort);
>  	if (ret) {
> +		drm_dp_mst_put_port_malloc(port);
>  		intel_connector_free(intel_connector);
>  		return NULL;
>  	}

Re: [PATCH] drm: i915: fix a possible refcount leak in intel_dp_add_mst_connector()

Posted by Hangyu Hua 3 years, 10 months ago

On 2022/5/16 15:19, Hangyu Hua wrote:
> If drm_connector_init fails, intel_connector_free will be called to take
> care of proper free. So it is necessary to drop the refcount of port
> before intel_connector_free.
> 
> Fixes: 091a4f91942a ("drm/i915: Handle drm-layer errors in intel_dp_add_mst_connector")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> ---
>   drivers/gpu/drm/i915/display/intel_dp_mst.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index e30e698aa684..f7d46ea3afb9 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -841,6 +841,7 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
>   	ret = drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs,
>   				 DRM_MODE_CONNECTOR_DisplayPort);
>   	if (ret) {
> +		drm_dp_mst_put_port_malloc(port);
>   		intel_connector_free(intel_connector);
>   		return NULL;
>   	}

Gentel ping.