From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     liviu.dudau@arm.com, brian.starkey@arm.com, airlied@linux.ie,
        daniel@ffwll.ch
Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH v2] drm: mali-dp: potential dereference of null pointer
Date:   Tue, 14 Dec 2021 20:51:10 +0800
Message-Id: <20211214125110.46979-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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@iscas.ac.cn>
Reported-by: Brian Starkey <brian.starkey@arm.com>
---
Changelog:

v1 -> v2

*Change 1. Add r-p.
---
 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)
-- 
2.25.1