From:   Rob Clark <robdclark@gmail.com>
To:     dri-devel@lists.freedesktop.org
Cc:     freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org,
        Rob Clark <robdclark@chromium.org>,
        Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>,
        Jordan Crouse <jordan@cosmicpenguin.net>,
        linux-kernel@vger.kernel.org (open list)
Subject: [PATCH] drm/msm: Fix potential invalid ptr free
Date:   Wed, 15 Feb 2023 15:50:48 -0800
Message-Id: <20230215235048.1166484-1-robdclark@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Rob Clark <robdclark@chromium.org>

The error path cleanup expects that chain and syncobj are either NULL or
valid pointers.  But post_deps was not allocated with __GFP_ZERO.

Fixes: ab723b7a992a ("drm/msm: Add syncobj support.")
Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/msm_gem_submit.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 6503220e5a4b..e4d13540300e 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -640,8 +640,8 @@ static struct msm_submit_post_dep *msm_parse_post_deps(struct drm_device *dev,
 	int ret = 0;
 	uint32_t i, j;
 
-	post_deps = kmalloc_array(nr_syncobjs, sizeof(*post_deps),
-	                          GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
+	post_deps = kcalloc(nr_syncobjs, sizeof(*post_deps),
+			    GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
 	if (!post_deps)
 		return ERR_PTR(-ENOMEM);
 
@@ -656,7 +656,6 @@ static struct msm_submit_post_dep *msm_parse_post_deps(struct drm_device *dev,
 		}
 
 		post_deps[i].point = syncobj_desc.point;
-		post_deps[i].chain = NULL;
 
 		if (syncobj_desc.flags) {
 			ret = -EINVAL;
-- 
2.39.1