This is a note to let you know that I've just added the patch titled drm/arm/malidp: fix a possible null pointer dereference to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-arm-malidp-fix-a-possible-null-pointer-dereferen.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 5c9987a3e04729271b5ceaeb93b88dad5b8f37c9 Author: Huai-Yuan Liu <qq810974084@xxxxxxxxx> Date: Sun Apr 7 14:30:53 2024 +0800 drm/arm/malidp: fix a possible null pointer dereference [ Upstream commit a1f95aede6285dba6dd036d907196f35ae3a11ea ] In malidp_mw_connector_reset, new memory is allocated with kzalloc, but no check is performed. In order to prevent null pointer dereferencing, ensure that mw_state is checked before calling __drm_atomic_helper_connector_reset. Fixes: 8cbc5caf36ef ("drm: mali-dp: Add writeback connector") Signed-off-by: Huai-Yuan Liu <qq810974084@xxxxxxxxx> Signed-off-by: Liviu Dudau <liviu.dudau@xxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20240407063053.5481-1-qq810974084@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c index 7266d3c8b8f41..420efbdea76c3 100644 --- a/drivers/gpu/drm/arm/malidp_mw.c +++ b/drivers/gpu/drm/arm/malidp_mw.c @@ -69,7 +69,10 @@ 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); + connector->state = NULL; + + if (mw_state) + __drm_atomic_helper_connector_reset(connector, &mw_state->base); } static enum drm_connector_status