[Intel-gfx] [PATCH RESEND] drm: i915: fix a possible refcount leak in intel_dp_add_mst_connector()

[Lyude Paul]

Nice catch!

Reviewed-by: Lyude Paul <lyude at redhat.com>

Will push to drm-intel-next

On Fri, 2022-06-24 at 10:28 +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.
> 
> Fixes: 091a4f91942a ("drm/i915: Handle drm-layer errors in
> intel_dp_add_mst_connector")
> Signed-off-by: Hangyu Hua <hbh25y at gmail.com>
> Reviewed-by: José Roberto de Souza <jose.souza at intel.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 061b277e5ce7..14d2a64193b2 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -839,6 +839,7 @@ 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;
>         }

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat