[PATCH AUTOSEL 6.6 085/139] drm/amdgpu: disallow multiple BO_HANDLES chunks in one submit

[Sasha Levin]

From: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer at amd.com>

[ 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 at amd.com>
Reviewed-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index e361dc37a0890..7abcd618e70bd 100644
--- 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;
-- 
2.43.0