This is a note to let you know that I've just added the patch titled
drm/mediatek: Add 0 size check to mtk_drm_gem_obj
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-mediatek-add-0-size-check-to-mtk_drm_gem_obj.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 ac94087ab05762d61489b865384df2b43f0ca590
Author: Justin Green <greenjustin@xxxxxxxxxxxx>
Date: Thu Mar 7 13:00:51 2024 -0500
drm/mediatek: Add 0 size check to mtk_drm_gem_obj
[ Upstream commit 1e4350095e8ab2577ee05f8c3b044e661b5af9a0 ]
Add a check to mtk_drm_gem_init if we attempt to allocate a GEM object
of 0 bytes. Currently, no such check exists and the kernel will panic if
a userspace application attempts to allocate a 0x0 GBM buffer.
Tested by attempting to allocate a 0x0 GBM buffer on an MT8188 and
verifying that we now return EINVAL.
Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Signed-off-by: Justin Green <greenjustin@xxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20240307180051.4104425-1-greenjustin@xxxxxxxxxxxx/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
index b09a37a38e0ae..079df67892df5 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -26,6 +26,9 @@ static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev,
size = round_up(size, PAGE_SIZE);
+ if (size == 0)
+ return ERR_PTR(-EINVAL);
+
mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
if (!mtk_gem_obj)
return ERR_PTR(-ENOMEM);
