{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98510", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.354Z", "datePublished": "2026-10-18T15:17:20.805Z", "dateUpdated": "2026-10-24T14:09:11.598Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:09:11.598Z" }, "descriptions": [ { "lang": "en", "value": "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)" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - A local render-node client reaches the patched xe_vm_close_and_put() through DRM_IOCTL_XE_VM_DESTROY -> xe_vm_destroy_ioctl() or file close -> xe_file_close(); the competing path is another local DRM ioctl, not wire-supplied data.\nAC:L - The same client can bind an external BO to a fault-mode VM and race VM_DESTROY against PREFETCH from a second VM; PREFETCH reaches xe_bo_migrate() -> xe_bo_move_notify() -> xe_bo_trigger_rebind(), so the attacker controls both sides.\nPR:L - XE_VM_CREATE, XE_GEM_CREATE, XE_VM_BIND, and XE_VM_DESTROY are registered with DRM_RENDER_ALLOW and contain no capability or DRM-authentication check, making the path available to an unprivileged user with render-node access.\nUI:N - The attacking process creates the VM and external BO, establishes the immediate mapping, and issues both the destroy and migration operations itself; no victim action is required.\nS:U - The fault occurs in the host xe DRM driver while processing that driver's local render-node operations and does not cross a VM, IOMMU, or other security authority boundary.\nC:H - xe_vm_close_and_put() leaves the VMA linked while xe_pt_destroy() recursively kfree()s PT nodes with vm->pt_root still published; a racing xe_pt_zap_ptes() can therefore walk heap-groomable freed PT metadata and dereference stale object pointers.\nI:H - In the UAF interleaving, xe_pt_zap_ptes_entry() uses the freed metadata's xe_child->bo->vmap as the destination for xe_map_memset(), allowing a groomed stale pointer to redirect writes and potentially corrupt control flow.\nA:H - In the documented interleaving, xe_vm_pt_destroy() sets vm->pt_root[tile->id] to NULL and xe_pt_zap_ptes() dereferences pt->level, producing the reported kernel NULL-pointer oops." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/xe/xe_vm.c" ], "versions": [ { "version": "b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc", "lessThan": "70fddc065ac80845ffd33095b3635d59883cf7e6", "status": "affected", "versionType": "git" }, { "version": "b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc", "lessThan": "ba678c2b02e0d36b53deb5a6d5e5ea044d36def7", "status": "affected", "versionType": "git" }, { "version": "b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc", "lessThan": "bddaa5e4094c134452c29e20a26c4718827e4cb1", "status": "affected", "versionType": "git" }, { "version": "b06d47be7c83165d3b3e45e1d5f9520b79c7f5cc", "lessThan": "24a22fb3c731474b68e986af6804db450fb88617", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/gpu/drm/xe/xe_vm.c" ], "versions": [ { "version": "6.8", "status": "affected" }, { "version": "0", "lessThan": "6.8", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.18.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.3" } ] } ] } ], "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" } ], "title": "drm/xe/vm: nuke PTs only after unlinking contested VMAs", "x_generator": { "engine": "bippy-1.2.0" } } } }