{"id":"CVE-2026-98510","published":"2026-10-18T16:17:02.203","lastModified":"2026-10-19T10:19:04.493","description":"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_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)","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/24a22fb3c731474b68e986af6804db450fb88617","tags":[]},{"url":"https://git.kernel.org/stable/c/70fddc065ac80845ffd33095b3635d59883cf7e6","tags":[]},{"url":"https://git.kernel.org/stable/c/ba678c2b02e0d36b53deb5a6d5e5ea044d36def7","tags":[]},{"url":"https://git.kernel.org/stable/c/bddaa5e4094c134452c29e20a26c4718827e4cb1","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}