drm/amdgpu: disallow multiple BO_HANDLES chunks in one submit

[ Upstream commit fec5f8e8c6bcf83ed7a392801d7b44c5ecfc1e82 ]

Before this commit, only submits with both a BO_HANDLES chunk and a
'bo_list_handle' would be rejected (by amdgpu_cs_parser_bos).

But if UMD sent multiple BO_HANDLES, what would happen is:
* only the last one would be really used
* all the others would leak memory as amdgpu_cs_p1_bo_handles would
  overwrite the previous p->bo_list value

This commit rejects submissions with multiple BO_HANDLES chunks to
match the implementation of the parser.

Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 6dfdff58bffd1fb4819e11f6291a63a9b20af6d3..78b3c067fea7e276fcca711510861abfd90fcaf6 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -263,6 +263,10 @@ static int amdgpu_cs_pass1(struct amdgpu_cs_parser *p,
                        if (size < sizeof(struct drm_amdgpu_bo_list_in))
                                goto free_partial_kdata;
 
+                       /* Only a single BO list is allowed to simplify handling. */
+                       if (p->bo_list)
+                               ret = -EINVAL;
+
                        ret = amdgpu_cs_p1_bo_handles(p, p->chunks[i].kdata);
                        if (ret)
                                goto free_partial_kdata;