[PATCH 5.17 075/146] drm/msm/mdp5: check the return of kzalloc()

From: Greg Kroah-Hartman
Date: Tue Apr 26 2022 - 05:29:11 EST

From: Xiaoke Wang <xkernel.wang@xxxxxxxxxxx>

[ Upstream commit 047ae665577776b7feb11bd4f81f46627cff95e7 ]

kzalloc() is a memory allocation function which can return NULL when
some internal memory errors happen. So it is better to check it to
prevent potential wrong memory access.

Besides, since mdp5_plane_reset() is void type, so we should better
set `plane-state` to NULL after releasing it.

Signed-off-by: Xiaoke Wang <xkernel.wang@xxxxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Patchwork: https://patchwork.freedesktop.org/patch/481055/
Link: https://lore.kernel.org/r/tencent_8E2A1C78140EE1784AB2FF4B2088CC0AB908@xxxxxx
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
index c6b69afcbac8..50e854207c70 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
@@ -90,7 +90,10 @@ static void mdp5_plane_reset(struct drm_plane *plane)

+ plane->state = NULL;
mdp5_state = kzalloc(sizeof(*mdp5_state), GFP_KERNEL);
+ if (!mdp5_state)
+ return;

if (plane->type == DRM_PLANE_TYPE_PRIMARY)
mdp5_state->base.zpos = STAGE_BASE;