[PATCH 6.11 178/214] drm/i915/hdcp: fix connector refcounting

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

6.11-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jani Nikula <jani.nikula@xxxxxxxxx>

commit 4cc2718f621a6a57a02581125bb6d914ce74d23b upstream.

We acquire a connector reference before scheduling an HDCP prop work,
and expect the work function to release the reference.

However, if the work was already queued, it won't be queued multiple
times, and the reference is not dropped.

Release the reference immediately if the work was already queued.

Fixes: a6597faa2d59 ("drm/i915: Protect workers against disappearing connectors")
Cc: Sean Paul <seanpaul@xxxxxxxxxxxx>
Cc: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v5.10+
Reviewed-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240924153022.2255299-1-jani.nikula@xxxxxxxxx
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
(cherry picked from commit abc0742c79bdb3b164eacab24aea0916d2ec1cb5)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/i915/display/intel_hdcp.c |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -1089,7 +1089,8 @@ static void intel_hdcp_update_value(stru
 	hdcp->value = value;
 	if (update_property) {
 		drm_connector_get(&connector->base);
-		queue_work(i915->unordered_wq, &hdcp->prop_work);
+		if (!queue_work(i915->unordered_wq, &hdcp->prop_work))
+			drm_connector_put(&connector->base);
 	}
 }
 
@@ -2517,7 +2518,8 @@ void intel_hdcp_update_pipe(struct intel
 		mutex_lock(&hdcp->mutex);
 		hdcp->value = DRM_MODE_CONTENT_PROTECTION_DESIRED;
 		drm_connector_get(&connector->base);
-		queue_work(i915->unordered_wq, &hdcp->prop_work);
+		if (!queue_work(i915->unordered_wq, &hdcp->prop_work))
+			drm_connector_put(&connector->base);
 		mutex_unlock(&hdcp->mutex);
 	}
 
@@ -2534,7 +2536,9 @@ void intel_hdcp_update_pipe(struct intel
 		 */
 		if (!desired_and_not_enabled && !content_protection_type_changed) {
 			drm_connector_get(&connector->base);
-			queue_work(i915->unordered_wq, &hdcp->prop_work);
+			if (!queue_work(i915->unordered_wq, &hdcp->prop_work))
+				drm_connector_put(&connector->base);
+
 		}
 	}