This is a note to let you know that I've just added the patch titled
drm/amdgpu: Fix potential fence use-after-free v2
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amdgpu-fix-potential-fence-use-after-free-v2.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f49632c56ca0d84e311ee22e688ea83c3d4abc4d
Author: shanzhulig <shanzhulig@xxxxxxxxx>
Date: Tue Jun 27 18:10:47 2023 -0700
drm/amdgpu: Fix potential fence use-after-free v2
[ Upstream commit 2e54154b9f27262efd0cb4f903cc7d5ad1fe9628 ]
fence Decrements the reference count before exiting.
Avoid Race Vulnerabilities for fence use-after-free.
v2 (chk): actually fix the use after free and not just move it.
Signed-off-by: shanzhulig <shanzhulig@xxxxxxxxx>
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index e667bcf64bc7f..70e446c2acf82 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -1502,15 +1502,15 @@ static int amdgpu_cs_wait_all_fences(struct amdgpu_device *adev,
continue;
r = dma_fence_wait_timeout(fence, true, timeout);
+ if (r > 0 && fence->error)
+ r = fence->error;
+
dma_fence_put(fence);
if (r < 0)
return r;
if (r == 0)
break;
-
- if (fence->error)
- return fence->error;
}
memset(wait, 0, sizeof(*wait));
