As kzalloc may fail and return NULL pointer, the "mw_state" can be NULL. If the the layout of struct malidp_mw_connector_state ever changes, it will cause NULL poineter derefernce of "&mw_state->base". Therefore, the "mw_state" should be check whether it is NULL in order to improve the robust. Fixes: 8cbc5caf36ef ("drm: mali-dp: Add writeback connector") Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> --- drivers/gpu/drm/arm/malidp_mw.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c index ef76d0e6ee2f..c74c7c4e6006 100644 --- a/drivers/gpu/drm/arm/malidp_mw.c +++ b/drivers/gpu/drm/arm/malidp_mw.c @@ -72,7 +72,11 @@ static void malidp_mw_connector_reset(struct drm_connector *connector) __drm_atomic_helper_connector_destroy_state(connector->state); kfree(connector->state); - __drm_atomic_helper_connector_reset(connector, &mw_state->base); + + if (mw_state) + __drm_atomic_helper_connector_reset(connector, &mw_state->base); + else: + __drm_atomic_helper_connector_reset(connector, NULL); } static enum drm_connector_status -- 2.25.1