2022-03-25 17:34:29

by Xiaoke Wang

Subject: [PATCH] drm: mali-dp: check the return value of kzalloc()

From: Xiaoke Wang <[email protected]>

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.

Signed-off-by: Xiaoke Wang <[email protected]>
---
drivers/gpu/drm/arm/malidp_mw.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c
index f5847a7..0720b21 100644
--- a/drivers/gpu/drm/arm/malidp_mw.c
+++ b/drivers/gpu/drm/arm/malidp_mw.c
@@ -70,7 +70,10 @@ 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);
+ connector->state = NULL;
+
+ if (mw_state)
+ __drm_atomic_helper_connector_reset(connector, &mw_state->base);
}

static enum drm_connector_status
--

2022-03-25 19:52:53

by Xiaoke Wang

Subject: Re:[PATCH] drm: mali-dp: check the return value of kzalloc()

Thu, 24 Mar 2022 14:43:17 +0800, [email protected] wrote:

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

Withdraw this. The original code is also fine since there is a valid check
inside __drm_atomic_helper_connector_reset() but I missed to track it.