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vuln-cve/data/2026/98xxx/CVE-2026-98510.json
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{
"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"
}
}
}
}