CVE-2026-89445

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix UAF in selftest IOPF reporting IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from group->pasid_array without synchronizing against PASID detach, then a concurrent iommu_report_device_fault() can dereference that borrowed handle's domain pointer after the detach erases the handle and frees the backing struct iommufd_attach_handle. TRIGGER_IOPF then dereferences the freed handle, causing a UAF. Fix by adding a iopf_rwsem in mock_dev to follow the expected design of a real driver. Hold its read side across the whole iommu_report_device_fault() call, and its write side around every path that attaches, detaches, or replaces a device domain. This can block new reports and drains in-flight reports before an old attach handle or the IOPF fault parameter can be removed. Also take the write side while registering a mock device, since it can invoke the mock driver's default-domain attach callback.

Severity

HIGH

CVSS score

8.8 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-11 20:19:24.990000

Last modified

2026-10-19 09:17:36.597000

View original CVE JSON

{
  "id": "CVE-2026-89445",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:24.990",
  "lastModified": "2026-10-19T09:17:36.597",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommufd: Fix UAF in selftest IOPF reporting\n\nIOMMUFD selftest TRIGGER_IOPF borrows an attach handle from\ngroup->pasid_array without synchronizing against PASID detach,\nthen a concurrent iommu_report_device_fault() can dereference\nthat borrowed handle's domain pointer after the detach erases\nthe handle and frees the backing struct iommufd_attach_handle.\nTRIGGER_IOPF then dereferences the freed handle, causing a UAF.\n\nFix by adding a iopf_rwsem in mock_dev to follow the expected design\nof a real driver. Hold its read side across the whole\niommu_report_device_fault() call, and its write side around every\npath that attaches, detaches, or replaces a device domain.\nThis can block new reports and drains in-flight reports before an old\nattach handle or the IOPF fault parameter can be removed.\nAlso take the write side while registering a mock device, since\nit can invoke the mock driver's default-domain attach callback."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/iommu/iommufd/selftest.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "ddee19971081b42615d62f4fdada21274708ed4d",
              "lessThan": "fd2e7ac94d6d813548b021473c3dddc30c8c07d1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ddee19971081b42615d62f4fdada21274708ed4d",
              "lessThan": "cab2895729516799384d48560e6fca105fb3f927",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ddee19971081b42615d62f4fdada21274708ed4d",
              "lessThan": "e27e90bde68b2ab92e63ed19caad1ef57188bea0",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "ddee19971081b42615d62f4fdada21274708ed4d",
              "lessThan": "8c07df7cdfcf52f1ff276c588612aabc6c6b8399",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/iommu/iommufd/selftest.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.11",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.11",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.112",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "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:C/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.0,
        "impactScore": 6.0
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/8c07df7cdfcf52f1ff276c588612aabc6c6b8399",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cab2895729516799384d48560e6fca105fb3f927",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e27e90bde68b2ab92e63ed19caad1ef57188bea0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fd2e7ac94d6d813548b021473c3dddc30c8c07d1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}