Commit c6059af6 authored Jun 27, 2023 by shanzhulig Committed by Greg Kroah-Hartman Aug 30, 2023

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@gmail.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent fe49aa73

drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1575,15 +1575,15 @@ 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));