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FKIE_CVE-2026-89751

Vulnerability from fkie_nvd - Published: 2026-09-11 20:20 - Updated: 2026-09-14 13:19
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Fix off-by-one in port I/O handling handle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use: u64 mask = GENMASK(BITS_PER_BYTE * size, 0); GENMASK(h, l) includes bit h. For size=1 (INB), this produces GENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8 bits). The mask is one bit too wide for all I/O sizes. Fix the mask calculation.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/220011fe95fc78b2bc2d7d43893bc73957a5c811
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c6875423ad849ac234ab9812eb72f37ff8a490b4
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/coco/tdx/tdx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "c6875423ad849ac234ab9812eb72f37ff8a490b4",
              "status": "affected",
              "version": "03149948832a078f759022ed5b92e722d8d23c26",
              "versionType": "git"
            },
            {
              "lessThan": "220011fe95fc78b2bc2d7d43893bc73957a5c811",
              "status": "affected",
              "version": "03149948832a078f759022ed5b92e722d8d23c26",
              "versionType": "git"
            },
            {
              "lessThan": "222b7005e4519f633b4cd666226256abbab46a1a",
              "status": "affected",
              "version": "03149948832a078f759022ed5b92e722d8d23c26",
              "versionType": "git"
            },
            {
              "lessThan": "c4a22154870813d10aa0b4c734a574c726f9d4b0",
              "status": "affected",
              "version": "03149948832a078f759022ed5b92e722d8d23c26",
              "versionType": "git"
            },
            {
              "lessThan": "bb45f705c4440dd3c689328319b88dd28770bbb8",
              "status": "affected",
              "version": "03149948832a078f759022ed5b92e722d8d23c26",
              "versionType": "git"
            },
            {
              "lessThan": "0f63e656b1c679d32ac595de29d10c03efca6a25",
              "status": "affected",
              "version": "03149948832a078f759022ed5b92e722d8d23c26",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/coco/tdx/tdx.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.19"
            },
            {
              "lessThan": "5.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/tdx: Fix off-by-one in port I/O handling\n\nhandle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use:\n\n    u64 mask = GENMASK(BITS_PER_BYTE * size, 0);\n\nGENMASK(h, l) includes bit h. For size=1 (INB), this produces\nGENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8\nbits). The mask is one bit too wide for all I/O sizes.\n\nFix the mask calculation."
    }
  ],
  "id": "CVE-2026-89751",
  "lastModified": "2026-09-14T13:19:23.783",
  "metrics": {},
  "published": "2026-09-11T20:20:06.013",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/220011fe95fc78b2bc2d7d43893bc73957a5c811"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c6875423ad849ac234ab9812eb72f37ff8a490b4"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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