[PATCH] drm: mali-dp: Add check for kzalloc

From: Jiasheng Jiang
Date: Wed Dec 07 2022 - 21:13:05 EST


As kzalloc may fail and return NULL pointer, the "mw_state" can be NULL.
If the the layout of struct malidp_mw_connector_state ever changes, it
will cause NULL poineter derefernce of "&mw_state->base".
Therefore, the "mw_state" should be check whether it is NULL in order
to improve the robust.

Fixes: 8cbc5caf36ef ("drm: mali-dp: Add writeback connector")
Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
---
drivers/gpu/drm/arm/malidp_mw.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c
index ef76d0e6ee2f..c74c7c4e6006 100644
--- a/drivers/gpu/drm/arm/malidp_mw.c
+++ b/drivers/gpu/drm/arm/malidp_mw.c
@@ -72,7 +72,11 @@ 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);
+
+ if (mw_state)
+ __drm_atomic_helper_connector_reset(connector, &mw_state->base);
+ else:
+ __drm_atomic_helper_connector_reset(connector, NULL);
}

static enum drm_connector_status
--
2.25.1