drm/amdgpu: fix potential double drop fence reference

The object fence is not set to NULL after its reference is dropped. As a
result, its reference may be dropped again if error occurs after that,
which may lead to a use after free bug. To avoid the issue, fence is
explicitly set to NULL after dropping its reference.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Pan Bian 2019-11-06 17:14:45 +08:00 committed by Alex Deucher
parent f88e2d1f8e
commit 946ab8db69

View File

@ -138,6 +138,7 @@ static void amdgpu_do_test_moves(struct amdgpu_device *adev)
}
dma_fence_put(fence);
fence = NULL;
r = amdgpu_bo_kmap(vram_obj, &vram_map);
if (r) {
@ -183,6 +184,7 @@ static void amdgpu_do_test_moves(struct amdgpu_device *adev)
}
dma_fence_put(fence);
fence = NULL;
r = amdgpu_bo_kmap(gtt_obj[i], &gtt_map);
if (r) {