From 357b5592e018b0faa9d49f1f8b58a4966391bcbd Mon Sep 17 00:00:00 2001 From: Anshuman Gupta Date: Thu, 11 Feb 2021 19:35:02 +0530 Subject: drm/i915/debugfs: HDCP capability enc NULL check DP-MST connector encoder initializes at modeset Adding a connector->encoder NULL check in order to avoid any NULL pointer dereference. intel_hdcp_enable() already handle this but debugfs can also invoke the intel_{hdcp,hdcp2_capable}. Handling it gracefully. v2: - Use necessary lock and NULL check in i915_hdcp_sink_capability_show. [Imre] Reviewed-by: Imre Deak Signed-off-by: Anshuman Gupta Link: https://patchwork.freedesktop.org/patch/msgid/20210211140502.22786-1-anshuman.gupta@intel.com --- drivers/gpu/drm/i915/display/intel_display_debugfs.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'drivers/gpu/drm/i915/display/intel_display_debugfs.c') diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c index d6e4a9237bda..8af663b84314 100644 --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c @@ -2198,16 +2198,27 @@ DEFINE_SHOW_ATTRIBUTE(i915_panel); static int i915_hdcp_sink_capability_show(struct seq_file *m, void *data) { struct drm_connector *connector = m->private; + struct drm_i915_private *i915 = to_i915(connector->dev); struct intel_connector *intel_connector = to_intel_connector(connector); + int ret; - if (connector->status != connector_status_connected) - return -ENODEV; + ret = drm_modeset_lock_single_interruptible(&i915->drm.mode_config.connection_mutex); + if (ret) + return ret; + + if (!connector->encoder || connector->status != connector_status_connected) { + ret = -ENODEV; + goto out; + } seq_printf(m, "%s:%d HDCP version: ", connector->name, connector->base.id); intel_hdcp_info(m, intel_connector); - return 0; +out: + drm_modeset_unlock(&i915->drm.mode_config.connection_mutex); + + return ret; } DEFINE_SHOW_ATTRIBUTE(i915_hdcp_sink_capability); -- cgit v1.2.3