From: Junrui Luo <[email protected]>
amdgpu_cs_pass1() dispatches on chunk_id once per chunk without
rejecting repeated ids. p->uf_bo is a single-slot field, so a
submission carrying two AMDGPU_CHUNK_ID_FENCE chunks runs
amdgpu_cs_p1_user_fence() twice, and the second run overwrites
p->uf_bo with a freshly referenced BO without dropping the reference
taken by the first.
amdgpu_cs_parser_fini() only unrefs the final p->uf_bo, so every FENCE
chunk but the last leaks a BO reference. The leaked BO outlives handle
close and process exit.
Reject duplicate FENCE chunks the same way commit fec5f8e8c6bc
("drm/amdgpu: disallow multiple BO_HANDLES chunks in one submit") did
for p->bo_list.
Fixes: d38ceaf99ed0 ("drm/amdgpu: add core driver (v4)")
Reported-by: Yuhao Jiang <[email protected]>
Assisted-by: Claude:claude-opus-5
Cc: [email protected]
Signed-off-by: Junrui Luo <[email protected]>
---
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 5445f75741b5..9c514cb01096 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -228,6 +228,10 @@ static int amdgpu_cs_pass1(struct amdgpu_cs_parser *p,
if (size < sizeof(struct drm_amdgpu_cs_chunk_fence))
goto free_partial_kdata;
+ /* Only a single user fence is allowed to simplify
handling. */
+ if (p->uf_bo)
+ goto free_partial_kdata;
+
ret = amdgpu_cs_p1_user_fence(p, p->chunks[i].kdata,
&uf_offset);
if (ret)
--
2.51.2
