CVE-2026-90244
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: iommu/dma: Restore locking around msi_page_list Unlike a group's default domain, which is always freshly allocated and privately owned (iommu_group_alloc_default_domain()), VFIO type1's legacy container merges any newly attached group into an existing domain whenever their iommu_ops and cache-coherency enforcement match. iommu_dma_get_msi_page() only asserts the caller's own group mutex is held (iommu_group_mutex_assert()). On an IOMMU that publishes IOMMU_RESV_SW_MSI, e.g. ARM SMMU, a VM with two such devices assigned through the legacy container can have their guest drivers probe and allocate MSIs in parallel; each host-side VFIO_DEVICE_SET_IRQS lands on a different device fd and group mutex, but both devices' domains are the same merged domain, so both can enter iommu_dma_get_msi_page() concurrently and corrupt msi_page_list. commit 288683c92b1a ("iommu: Make iommu_dma_prepare_msi() into a generic operation") dropped the prior msi_prepare_lock on the reasoning that "each iommu_domain is unique to a group," which holds for default domains but not this VFIO type1 case. Restore the static lock, since it's only guarding a corner case and will likely never be contended. iommufd avoids the equivalent problem by having its own callers (iommufd_sw_map_msi()) take a ctx-wide sw_msi_lock before ever reaching the shared list. VFIO type1 can't mirror that since it dispatches to iommu_dma_sw_msi() which is outside VFIO's jurisdiction.
View original CVE JSON
{
"id": "CVE-2026-90244",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-17T17:17:20.400",
"lastModified": "2026-10-19T09:19:14.897",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/dma: Restore locking around msi_page_list\n\nUnlike a group's default domain, which is always freshly allocated\nand privately owned (iommu_group_alloc_default_domain()), VFIO type1's\nlegacy container merges any newly attached group into an existing\ndomain whenever their iommu_ops and cache-coherency enforcement match.\n\niommu_dma_get_msi_page() only asserts the caller's own group mutex is\nheld (iommu_group_mutex_assert()). On an IOMMU that publishes\nIOMMU_RESV_SW_MSI, e.g. ARM SMMU, a VM with two such devices assigned\nthrough the legacy container can have their guest drivers probe and\nallocate MSIs in parallel; each host-side VFIO_DEVICE_SET_IRQS lands\non a different device fd and group mutex, but both devices' domains\nare the same merged domain, so both can enter\niommu_dma_get_msi_page() concurrently and corrupt msi_page_list.\n\ncommit 288683c92b1a (\"iommu: Make iommu_dma_prepare_msi() into a\ngeneric operation\") dropped the prior msi_prepare_lock on the\nreasoning that \"each iommu_domain is unique to a group,\" which holds\nfor default domains but not this VFIO type1 case. Restore the static\nlock, since it's only guarding a corner case and will likely never\nbe contended.\n\niommufd avoids the equivalent problem by having its own callers\n(iommufd_sw_map_msi()) take a ctx-wide sw_msi_lock before ever\nreaching the shared list. VFIO type1 can't mirror that since it\ndispatches to iommu_dma_sw_msi() which is outside VFIO's jurisdiction."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/iommu/dma-iommu.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "288683c92b1abc32277c83819bea287af614d239",
"lessThan": "e3c53e9173a47d5ce1fae020f2c6b1fb3c1123c2",
"versionType": "git",
"status": "affected"
},
{
"version": "288683c92b1abc32277c83819bea287af614d239",
"lessThan": "2af1e99ec14d226d66ceb9f16c663ee2568e6676",
"versionType": "git",
"status": "affected"
},
{
"version": "288683c92b1abc32277c83819bea287af614d239",
"lessThan": "5a9e89ea34e0e34ac5d7e949042d665533549e40",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"drivers/iommu/dma-iommu.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.15",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.15",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.52",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.6",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"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",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/2af1e99ec14d226d66ceb9f16c663ee2568e6676",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5a9e89ea34e0e34ac5d7e949042d665533549e40",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e3c53e9173a47d5ce1fae020f2c6b1fb3c1123c2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}