CVE-2026-80618
N/AIn the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Avoid double-unpin of DOORBELL/MMIO BOs on free amdgpu_amdkfd_gpuvm_free_memory_of_gpu() unpinned DOORBELL and MMIO remap BOs (which are pinned at allocation time) before checking whether the BO is still mapped to the GPU. When the BO is still mapped, the function returns -EBUSY and leaves the BO alive, but it has already been unpinned. The BO is then unpinned again when it is finally freed during process teardown, triggering a ttm_bo_unpin() underflow warning: WARNING: CPU: 18 PID: 15066 at ttm/ttm_bo.c:650 amdttm_bo_unpin+0x6d/0x80 [amdttm] Workqueue: kfd_process_wq kfd_process_wq_release [amdgpu] RIP: 0010:amdttm_bo_unpin+0x6d/0x80 [amdttm] Call Trace: amdgpu_bo_unpin+0x1a/0x90 [amdgpu] amdgpu_amdkfd_gpuvm_unpin_bo+0x31/0xb0 [amdgpu] amdgpu_amdkfd_gpuvm_free_memory_of_gpu+0x3bf/0x460 [amdgpu] kfd_process_free_outstanding_kfd_bos+0xd4/0x170 [amdgpu] kfd_process_wq_release+0x109/0x1b0 [amdgpu] process_one_work+0x1e2/0x3b0 worker_thread+0x50/0x3a0 kthread+0xdd/0x100 ret_from_fork+0x29/0x50 Move the unpin after the mapped_to_gpu_memory check so it only happens once we are committed to freeing the BO. (cherry picked from commit 927c5b2defb9b09856444d94bebfd056a002bd75)
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 7th percentile
Impact if exploited
—CVSS · not scored
- No impact metrics
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-80618/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-80618/poc.json
References
Technical & other
- https://git.kernel.org/stable/c/461ae406ae12107ebb321cabe561434c27aaea58
- https://git.kernel.org/stable/c/283e77af49fda96aaa57709fc5408b55ffec075e
- https://git.kernel.org/stable/c/c055a2088b719e9a4b580685e0ca97f9554a41a8
- https://git.kernel.org/stable/c/0e27d92f69b8e4c750a4b181cc05a86b9338c4f5
- https://git.kernel.org/stable/c/1d12ae8b079e173107abec0e5817332954c8e95f
- https://git.kernel.org/stable/c/3f0cc1735273a57c5116710cf0202e12152f59cc