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FKIE_CVE-2026-23067

Vulnerability from fkie_nvd - Published: 2026-02-04 17:16 - Updated: 2026-06-17 10:20
Summary
In the Linux kernel, the following vulnerability has been resolved: iommu/io-pgtable-arm: fix size_t signedness bug in unmap path __arm_lpae_unmap() returns size_t but was returning -ENOENT (negative error code) when encountering an unmapped PTE. Since size_t is unsigned, -ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE on 64-bit systems). This corrupted value propagates through the call chain: __arm_lpae_unmap() returns -ENOENT as size_t -> arm_lpae_unmap_pages() returns it -> __iommu_unmap() adds it to iova address -> iommu_pgsize() triggers BUG_ON due to corrupted iova This can cause IOVA address overflow in __iommu_unmap() loop and trigger BUG_ON in iommu_pgsize() from invalid address alignment. Fix by returning 0 instead of -ENOENT. The WARN_ON already signals the error condition, and returning 0 (meaning "nothing unmapped") is the correct semantic for size_t return type. This matches the behavior of other io-pgtable implementations (io-pgtable-arm-v7s, io-pgtable-dart) which return 0 on error conditions.
Impacted products

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/iommu/io-pgtable-arm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "41ec6988547819756fb65e94fc24f3e0dddf84ac",
              "status": "affected",
              "version": "3318f7b5cefbff96b1bb49584ac38d2c9997a830",
              "versionType": "git"
            },
            {
              "lessThan": "374e7af67d9d9d6103c2cfc8eb32abfecf3a2fd8",
              "status": "affected",
              "version": "3318f7b5cefbff96b1bb49584ac38d2c9997a830",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/iommu/io-pgtable-arm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.19",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "467E1359-7F6A-4790-AC45-172024944460",
              "versionEndExcluding": "6.18.8",
              "versionStartIncluding": "6.16",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "3EF854A1-ABB1-4E93-BE9A-44569EC76C0D",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/io-pgtable-arm: fix size_t signedness bug in unmap path\n\n__arm_lpae_unmap() returns size_t but was returning -ENOENT (negative\nerror code) when encountering an unmapped PTE. Since size_t is unsigned,\n-ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE\non 64-bit systems).\n\nThis corrupted value propagates through the call chain:\n  __arm_lpae_unmap() returns -ENOENT as size_t\n  -\u003e arm_lpae_unmap_pages() returns it\n  -\u003e __iommu_unmap() adds it to iova address\n  -\u003e iommu_pgsize() triggers BUG_ON due to corrupted iova\n\nThis can cause IOVA address overflow in __iommu_unmap() loop and\ntrigger BUG_ON in iommu_pgsize() from invalid address alignment.\n\nFix by returning 0 instead of -ENOENT. The WARN_ON already signals\nthe error condition, and returning 0 (meaning \"nothing unmapped\")\nis the correct semantic for size_t return type. This matches the\nbehavior of other io-pgtable implementations (io-pgtable-arm-v7s,\nio-pgtable-dart) which return 0 on error conditions."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\niommu/io-pgtable-arm: correcci\u00f3n de error de signo de size_t en la ruta de desmapeo\n\n__arm_lpae_unmap() devuelve size_t pero estaba devolviendo -ENOENT (c\u00f3digo de error negativo) al encontrar una PTE no mapeada. Dado que size_t no tiene signo, -ENOENT (t\u00edpicamente -2) se convierte en un valor positivo enorme (0xFFFFFFFFFFFFFFFE en sistemas de 64 bits).\n\nEste valor corrupto se propaga a trav\u00e9s de la cadena de llamadas:\n  __arm_lpae_unmap() devuelve -ENOENT como size_t\n  -\u0026gt; arm_lpae_unmap_pages() lo devuelve\n  -\u0026gt; __iommu_unmap() lo a\u00f1ade a la direcci\u00f3n iova\n  -\u0026gt; iommu_pgsize() activa BUG_ON debido a iova corrupta\n\nEsto puede causar un desbordamiento de direcci\u00f3n IOVA en el bucle de __iommu_unmap() y activar BUG_ON en iommu_pgsize() por una alineaci\u00f3n de direcci\u00f3n inv\u00e1lida.\n\nSe corrige devolviendo 0 en lugar de -ENOENT. El WARN_ON ya se\u00f1ala la condici\u00f3n de error, y devolver 0 (que significa \u0027nada desmapeado\u0027) es la sem\u00e1ntica correcta para el tipo de retorno size_t. Esto coincide con el comportamiento de otras implementaciones de io-pgtable (io-pgtable-arm-v7s, io-pgtable-dart) que devuelven 0 en condiciones de error."
    }
  ],
  "id": "CVE-2026-23067",
  "lastModified": "2026-06-17T10:20:48.273",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-02-04T17:16:17.403",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/374e7af67d9d9d6103c2cfc8eb32abfecf3a2fd8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/41ec6988547819756fb65e94fc24f3e0dddf84ac"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-617"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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