[PATCH 5.15 208/667] drm: mali-dp: potential dereference of null pointer

From: Greg Kroah-Hartman
Date: Tue Jun 07 2022 - 14:41:58 EST


From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

[ Upstream commit 73c3ed7495c67b8fbdc31cf58e6ca8757df31a33 ]

The return value of kzalloc() needs to be checked.
To avoid use of null pointer '&state->base' in case of the
failure of alloc.

Fixes: 99665d072183 ("drm: mali-dp: add malidp_crtc_state struct")
Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Reviewed-by: Brian Starkey <brian.starkey@xxxxxxx>
Signed-off-by: Liviu Dudau <liviu.dudau@xxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214100837.46912-1-jiasheng@xxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/arm/malidp_crtc.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/arm/malidp_crtc.c b/drivers/gpu/drm/arm/malidp_crtc.c
index 494075ddbef6..b5928b52e279 100644
--- a/drivers/gpu/drm/arm/malidp_crtc.c
+++ b/drivers/gpu/drm/arm/malidp_crtc.c
@@ -487,7 +487,10 @@ static void malidp_crtc_reset(struct drm_crtc *crtc)
if (crtc->state)
malidp_crtc_destroy_state(crtc, crtc->state);

- __drm_atomic_helper_crtc_reset(crtc, &state->base);
+ if (state)
+ __drm_atomic_helper_crtc_reset(crtc, &state->base);
+ else
+ __drm_atomic_helper_crtc_reset(crtc, NULL);
}

static int malidp_crtc_enable_vblank(struct drm_crtc *crtc)
--
2.35.1