drm/amdgpu: Fix out-of-bound access for gfx_v10_0_ring_test_ib()

The gfx_v10_0_ring_test_ib() function uses 20 bytes instead of 16
bytes during the test. The patch sets the size of the allocation to be
4-byte larger to match the actual usage.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Haohui Mai <ricetons@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c
index 5444616..407074f 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c
@@ -3830,8 +3830,7 @@ static int gfx_v10_0_ring_test_ib(struct amdgpu_ring *ring, long timeout)
        gpu_addr = adev->wb.gpu_addr + (index * 4);
        adev->wb.wb[index] = cpu_to_le32(0xCAFEDEAD);
        memset(&ib, 0, sizeof(ib));
-       r = amdgpu_ib_get(adev, NULL, 16,
-                                       AMDGPU_IB_POOL_DIRECT, &ib);
+       r = amdgpu_ib_get(adev, NULL, 20, AMDGPU_IB_POOL_DIRECT, &ib);
        if (r)
                goto err1;