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FKIE_CVE-2025-38220

Vulnerability from fkie_nvd - Published: 2025-07-04 14:15 - Updated: 2026-06-17 09:16
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: ext4: only dirty folios when data journaling regular files fstest generic/388 occasionally reproduces a crash that looks as follows: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> ext4_block_zero_page_range+0x30c/0x380 [ext4] ext4_truncate+0x436/0x440 [ext4] ext4_process_orphan+0x5d/0x110 [ext4] ext4_orphan_cleanup+0x124/0x4f0 [ext4] ext4_fill_super+0x262d/0x3110 [ext4] get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x26/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4ed/0x6b0 do_syscall_64+0x82/0x170 ... This occurs when processing a symlink inode from the orphan list. The partial block zeroing code in the truncate path calls ext4_dirty_journalled_data() -> folio_mark_dirty(). The latter calls mapping->a_ops->dirty_folio(), but symlink inodes are not assigned an a_ops vector in ext4, hence the crash. To avoid this problem, update the ext4_dirty_journalled_data() helper to only mark the folio dirty on regular files (for which a_ops is assigned). This also matches the journaling logic in the ext4_symlink() creation path, where ext4_handle_dirty_metadata() is called directly.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/be5f3061a6f904e3674257879e71881ceee5b673Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/cf6a4c4ac7b6e3214f25df594c9689a62f1bb456Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d7af6eee8cd60f55aa8c5fe2b91f11ec0c9a0f27Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e26268ff1dcae5662c1b96c35f18cfa6ab73d9dePatch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ext4/inode.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "cf6a4c4ac7b6e3214f25df594c9689a62f1bb456",
              "status": "affected",
              "version": "d84c9ebdac1e39bc7b036c0c829ee8c1956edabc",
              "versionType": "git"
            },
            {
              "lessThan": "be5f3061a6f904e3674257879e71881ceee5b673",
              "status": "affected",
              "version": "d84c9ebdac1e39bc7b036c0c829ee8c1956edabc",
              "versionType": "git"
            },
            {
              "lessThan": "d7af6eee8cd60f55aa8c5fe2b91f11ec0c9a0f27",
              "status": "affected",
              "version": "d84c9ebdac1e39bc7b036c0c829ee8c1956edabc",
              "versionType": "git"
            },
            {
              "lessThan": "e26268ff1dcae5662c1b96c35f18cfa6ab73d9de",
              "status": "affected",
              "version": "d84c9ebdac1e39bc7b036c0c829ee8c1956edabc",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ext4/inode.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.4"
            },
            {
              "lessThan": "6.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.95",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.35",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.15.*",
              "status": "unaffected",
              "version": "6.15.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.16",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F17A70D5-5B72-4411-9C16-98EF57D0C931",
              "versionEndExcluding": "6.6.95",
              "versionStartIncluding": "6.4",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "E569FD34-0076-4428-BE17-EECCF867611C",
              "versionEndExcluding": "6.12.35",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "DFD174C5-1AA2-4671-BDDC-1A9FCC753655",
              "versionEndExcluding": "6.15.4",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: only dirty folios when data journaling regular files\n\nfstest generic/388 occasionally reproduces a crash that looks as\nfollows:\n\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n...\nCall Trace:\n \u003cTASK\u003e\n ext4_block_zero_page_range+0x30c/0x380 [ext4]\n ext4_truncate+0x436/0x440 [ext4]\n ext4_process_orphan+0x5d/0x110 [ext4]\n ext4_orphan_cleanup+0x124/0x4f0 [ext4]\n ext4_fill_super+0x262d/0x3110 [ext4]\n get_tree_bdev_flags+0x132/0x1d0\n vfs_get_tree+0x26/0xd0\n vfs_cmd_create+0x59/0xe0\n __do_sys_fsconfig+0x4ed/0x6b0\n do_syscall_64+0x82/0x170\n ...\n\nThis occurs when processing a symlink inode from the orphan list. The\npartial block zeroing code in the truncate path calls\next4_dirty_journalled_data() -\u003e folio_mark_dirty(). The latter calls\nmapping-\u003ea_ops-\u003edirty_folio(), but symlink inodes are not assigned an\na_ops vector in ext4, hence the crash.\n\nTo avoid this problem, update the ext4_dirty_journalled_data() helper to\nonly mark the folio dirty on regular files (for which a_ops is\nassigned). This also matches the journaling logic in the ext4_symlink()\ncreation path, where ext4_handle_dirty_metadata() is called directly."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: solo folios sucios cuando se registran datos de archivos normales fstest generic/388 ocasionalmente reproduce un fallo que se parece a lo siguiente: ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000000 ... Seguimiento de llamadas: ext4_block_zero_page_range+0x30c/0x380 [ext4] ext4_truncate+0x436/0x440 [ext4] ext4_process_orphan+0x5d/0x110 [ext4] ext4_orphan_cleanup+0x124/0x4f0 [ext4] ext4_fill_super+0x262d/0x3110 [ext4] get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x26/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4ed/0x6b0 do_syscall_64+0x82/0x170 ... Esto ocurre al procesar un inodo de enlace simb\u00f3lico de la lista de hu\u00e9rfanos. El c\u00f3digo de puesta a cero parcial de bloques en la ruta de truncamiento llama a ext4_dirty_journalled_data() -\u0026gt; folio_mark_dirty(). Este \u00faltimo llama a mapping-\u0026gt;a_ops-\u0026gt;dirty_folio(), pero los inodos de enlace simb\u00f3lico no tienen asignado un vector a_ops en ext4, lo que explica el fallo. Para evitar este problema, actualice el asistente ext4_dirty_journalled_data() para que solo marque el folio como sucio en archivos normales (para los que se asigna a_ops). Esto tambi\u00e9n coincide con la l\u00f3gica de registro en la ruta de creaci\u00f3n de ext4_symlink(), donde se llama directamente a ext4_handle_dirty_metadata()."
    }
  ],
  "id": "CVE-2025-38220",
  "lastModified": "2026-06-17T09:16:24.937",
  "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": "2025-07-04T14:15:30.597",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/be5f3061a6f904e3674257879e71881ceee5b673"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/cf6a4c4ac7b6e3214f25df594c9689a62f1bb456"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/d7af6eee8cd60f55aa8c5fe2b91f11ec0c9a0f27"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e26268ff1dcae5662c1b96c35f18cfa6ab73d9de"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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