CVE-2026-80539

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: disallow multiple FENCE chunks in one submit 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. (cherry picked from commit 665b1fc2a1845206408f9a2c6da67101789edb82)

References

• https://git.kernel.org/stable/c/070229262ede37d17c4ea596650deb6e5eb5d106
• https://git.kernel.org/stable/c/5f46322e0b84af29e10eb951ff45bd6ea40640de
• https://git.kernel.org/stable/c/71aa45f7bfe46fbc6f51e7832573ff49b6005fea
• https://git.kernel.org/stable/c/931cd1d1baeae68e8eb2c23bc1f3d8934dca6241
• https://git.kernel.org/stable/c/e3ee74d6dbbe409eb99546a7b0a02b2782f9021d