{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98002", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:19:56.068Z", "datePublished": "2026-09-25T10:23:29.929Z", "dateUpdated": "2026-09-25T14:41:49.625Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-25T14:41:49.625Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/amd: Fix ineffective error check in nested domain allocation\n\namd_iommu_pdom_id_alloc() returns an int: a domain ID on success, or the\nnegative errno from ida_alloc_range() when the ID space is exhausted or\nmemory is short.  amd_iommu_alloc_domain_nested() stores that return value\nin gdom_info->hdom_id, which is a u32, and only then tests it:\n\n\tgdom_info->hdom_id = amd_iommu_pdom_id_alloc();\n\tif (gdom_info->hdom_id <= 0) {\n\nThe assignment discards the sign, so -ENOSPC becomes 0xffffffe4 and the\ntest never fires.  The nested domain is then set up with a host domain ID\nthat was never allocated, instead of the allocation failing with -ENOSPC.\n\nKeep the value in an int, test it there, and store it only once it is\nknown to be valid, which is what the other amd_iommu_pdom_id_alloc()\ncallers already do."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The patched function amd_iommu_alloc_domain_nested() is reached only via the IOMMU_HWPT_ALLOC ioctl on a local iommufd fd (/dev/iommu) against an AMD vIOMMU (iommufd_hwpt_alloc -> viommu->ops->alloc_domain_nested); no remote protocol carries the input.\nAC:H - The failure path needs ida_alloc_range() in amd_iommu_pdom_id_alloc() to fail: either all 65535 global host domain IDs are in use with a victim domain holding 0xffe4, which lowest-first allocation doesn't let the attacker arrange on demand, or a GFP_ATOMIC failure the attacker cannot force.\nPR:L - Needs a VMM-style user that has been given /dev/iommu (0660) and a bound VFIO device cdev to create a vIOMMU and nested HWPTs; that is delegated device access, not full init-namespace root.\nUI:N - The attacker allocates the nested HWPTs and attaches the device themselves; nobody else has to do anything.\nS:C - The unallocated hdom_id (truncated to 0xffe4/0xfff4 by DTE_DOMID_MASK) is written into the DTE by set_dte_nested(), so the nested device shares IOTLB tags with another IOMMU domain, breaking the DMA isolation boundary between domains.\nC:H - Because the DomID is aliased, the device's DMA can hit IOTLB translations cached for the other domain and read memory belonging to that domain.\nI:H - The same aliased IOTLB entries let the device's DMA writes land in the other domain's pages, corrupting memory outside the nested domain.\nA:H - Stray DMA writes into another domain's memory, plus invalidations for the parent S2 hitting the shared hdom_id, can corrupt host or guest memory used by other devices and bring them down."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/iommu/amd/nested.c"], "versions": [{"version": "757d2b1fdf5b7d6eead5963a49b5780617987ab8", "lessThan": "80c231f5577229d1e90a1e312b3095f9502f8625", "status": "affected", "versionType": "git"}, {"version": "757d2b1fdf5b7d6eead5963a49b5780617987ab8", "lessThan": "fa5c0827f0b7bac6d0a188f10118151769ae68fd", "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/iommu/amd/nested.c"], "versions": [{"version": "7.0", "status": "affected"}, {"version": "0", "lessThan": "7.0", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.7", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3-rc3", "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": "7.0", "versionEndExcluding": "7.2.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndExcluding": "7.3-rc3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/80c231f5577229d1e90a1e312b3095f9502f8625"}, {"url": "https://git.kernel.org/stable/c/fa5c0827f0b7bac6d0a188f10118151769ae68fd"}], "title": "iommu/amd: Fix ineffective error check in nested domain allocation", "x_generator": {"engine": "bippy-1.2.0"}}}}