[Why] When preferred_mode is NULL a null pointer dereference can occur when trying to get the preferred refresh in create_stream_for_sink. [How] Only query preferred_refresh when preferred_mode is not NULL. Consider preferred_refresh if it is since it's only being used to compare to the previous value. Fixes: b333730d126e ("drm/amd/display: Fix Scaling (RMX_*) for DC driver") Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index ce00e56814ed..478fa810438e 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2848,7 +2848,7 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector, bool native_mode_found = false; bool scale = dm_state ? (dm_state->scaling != RMX_OFF) : false; int mode_refresh; - int preferred_refresh; + int preferred_refresh = 0; struct dc_sink *sink = NULL; if (aconnector == NULL) { @@ -2907,7 +2907,8 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector, if (!dm_state) drm_mode_set_crtcinfo(&mode, 0); - preferred_refresh = drm_mode_vrefresh(preferred_mode); + if (preferred_mode) + preferred_refresh = drm_mode_vrefresh(preferred_mode); /* * If scaling is enabled and refresh rate didn't change -- 2.17.1 _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx