{"id":"CVE-2026-98510","title":"drm/xe/vm: nuke PTs only after unlinking contested VMAs","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/vm: nuke PTs only after unlinking contested VMAs\n\nIn xe_vm_close_and_put(), external-BO VMAs are queued on the contested\nlist for deferred destruction via xe_vma…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < 70fddc065ac80845ffd33095b3635d59883cf7e6","Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < ba678c2b02e0d36b53deb5a6d5e5ea044d36def7","Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < bddaa5e4094c134452c29e20a26c4718827e4cb1","Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < 24a22fb3c731474b68e986af6804db450fb88617","Linux 6.8"],"published":"2026-10-18","updated":"2026-10-18","sourceUpdated":"2026-10-18T15:17:20.805Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98510","references":[{"url":"https://git.kernel.org/stable/c/70fddc065ac80845ffd33095b3635d59883cf7e6"},{"url":"https://git.kernel.org/stable/c/ba678c2b02e0d36b53deb5a6d5e5ea044d36def7"},{"url":"https://git.kernel.org/stable/c/bddaa5e4094c134452c29e20a26c4718827e4cb1"},{"url":"https://git.kernel.org/stable/c/24a22fb3c731474b68e986af6804db450fb88617"}],"tags":["cve.org"],"ingestedAt":"2026-10-18T15:45:12.285Z","slug":"CVE-2026-98510","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/vm: nuke PTs only after unlinking contested VMAs\n\nIn xe_vm_close_and_put(), external-BO VMAs are queued on the contested\nlist for deferred destruction via xe_vma_destroy_unlocked(). However,\nxe_vm_pt_destroy() was previously invoked before processing contested\nVMAs, destroying vm->pt_root while those VMAs were still linked to their\nrespective buffer objects (vm_bo->list.gpuva).\n\nIf a concurrent thread evicts one of those shared buffer objects,\nxe_bo_trigger_rebind() holding only bo->resv walks the BO's VMAs and, in\nfault mode, calls xe_vm_invalidate_vma() -> xe_pt_zap_ptes(). Because\nvm->pt_root[tile->id] is already NULL, dereferencing pt->level causes a\nNULL ptr deref.\n\nFix this by deferring xe_vm_free_scratch() and xe_vm_pt_destroy() until\nafter all contested VMAs have been unlinked and destroyed.\n\nUser is reporting hitting a NULL ptr deref in xe_pt_zap_ptes(), which\ncould be explained by this race.\n\n(cherry picked from commit c2863648959489767f08892fd6e90577d2ea0b6a)\n\n## Affected\n\n- `Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < 70fddc065ac80845ffd33095b3635d59883cf7e6`\n- `Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < ba678c2b02e0d36b53deb5a6d5e5ea044d36def7`\n- `Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < bddaa5e4094c134452c29e20a26c4718827e4cb1`\n- `Linux >= b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc < 24a22fb3c731474b68e986af6804db450fb88617`\n- `Linux 6.8`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}