From: shanzhulig Date: Wed, 28 Jun 2023 01:10:47 +0000 (-0700) Subject: drm/amdgpu: Fix potential fence use-after-free v2 X-Git-Tag: v5.15.128~107 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ef568da1fd843581e855c79a368209b752dea2c1;p=thirdparty%2Fkernel%2Fstable.git 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 Signed-off-by: Christian König Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index 2fd4d8ad7e40d..4b01188385b28 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -1541,15 +1541,15 @@ 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));