{"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"}}}}