From ea9bc8b9289a6e524f0b0eeafc09addb7cfac9fd Mon Sep 17 00:00:00 2001 From: Shashank Sharma Date: Thu, 15 Apr 2021 23:18:12 +0530 Subject: [PATCH] drm/amdgpu/dm: Fix NULL pointer crash during DP MST hotplug This patch checks the return value of the function dc_link_add_remote_sink before using it. This was causing a crash during consecutive hotplugs of DP MST displays. Cc: Harry Wentland Reviewed-by: Harry Wentland Signed-off-by: Shashank Sharma Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 73cdb9fe981a3..60bff5301da91 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -229,6 +229,11 @@ static int dm_dp_mst_get_modes(struct drm_connector *connector) (aconnector->edid->extensions + 1) * EDID_LENGTH, &init_params); + if (!dc_sink) { + DRM_ERROR("Unable to add a remote sink\n"); + return 0; + } + dc_sink->priv = aconnector; /* dc_link_add_remote_sink returns a new reference */ aconnector->dc_sink = dc_sink; -- 2.30.2