[PATCH 4.19 26/53] drm/msm/mdp5: check the return of kzalloc()

Greg Kroah-Hartman
2022-04-26T08:34:35Z

From: Xiaoke Wang <xkernel.wang@foxmail.com>

[ 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@foxmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/481055/
Link: https://lore.kernel.org/r/tencent_8E2A1C78140EE1784AB2FF4B2088CC0AB908@qq.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 1ddf07514de6..3d8eaa25bea0 100644
--- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
+++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c
@@ -188,7 +188,10 @@ static void mdp5_plane_reset(struct drm_plane *plane)
drm_framebuffer_unreference(plane->state->fb);

kfree(to_mdp5_plane_state(plane->state));
+ plane->state = NULL;
mdp5_state = kzalloc(sizeof(*mdp5_state), GFP_KERNEL);
+ if (!mdp5_state)
+ return;

/* assign default blend parameters */
mdp5_state->alpha = 255;
--
2.35.1