drm/i915/hdcp: Add encoder check in intel_hdcp_get_capability

Sometimes during hotplug scenario or suspend/resume scenario encoder is
not always initialized when intel_hdcp_get_capability add
a check to avoid kernel null pointer dereference.

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Dnyaneshwar Bhadane <dnyaneshwar.bhadane@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240722064451.3610512-2-suraj.kandpal@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 3ebe035f382ec914279cb83924ed2c6524bdf769..05402ae6b56944321c7a3227ed63a43b260c0015 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -203,11 +203,16 @@ int intel_hdcp_read_valid_bksv(struct intel_digital_port *dig_port,
 /* Is HDCP1.4 capable on Platform and Sink */
 bool intel_hdcp_get_capability(struct intel_connector *connector)
 {
-       struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
+       struct intel_digital_port *dig_port;
        const struct intel_hdcp_shim *shim = connector->hdcp.shim;
        bool capable = false;
        u8 bksv[5];
 
+       if (!intel_attached_encoder(connector))
+               return capable;
+
+       dig_port = intel_attached_dig_port(connector);
+
        if (!shim)
                return capable;