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FKIE_CVE-2024-49870

Vulnerability from fkie_nvd - Published: 2024-10-21 18:15 - Updated: 2026-06-17 08:00
Summary
In the Linux kernel, the following vulnerability has been resolved: cachefiles: fix dentry leak in cachefiles_open_file() A dentry leak may be caused when a lookup cookie and a cull are concurrent: P1 | P2 ----------------------------------------------------------- cachefiles_lookup_cookie cachefiles_look_up_object lookup_one_positive_unlocked // get dentry cachefiles_cull inode->i_flags |= S_KERNEL_FILE; cachefiles_open_file cachefiles_mark_inode_in_use __cachefiles_mark_inode_in_use can_use = false if (!(inode->i_flags & S_KERNEL_FILE)) can_use = true return false return false // Returns an error but doesn't put dentry After that the following WARNING will be triggered when the backend folder is umounted: ================================================================== BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img} still in use (1) [unmount of ext4 sda] WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70 CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25 RIP: 0010:umount_check+0x5d/0x70 Call Trace: <TASK> d_walk+0xda/0x2b0 do_one_tree+0x20/0x40 shrink_dcache_for_umount+0x2c/0x90 generic_shutdown_super+0x20/0x160 kill_block_super+0x1a/0x40 ext4_kill_sb+0x22/0x40 deactivate_locked_super+0x35/0x80 cleanup_mnt+0x104/0x160 ================================================================== Whether cachefiles_open_file() returns true or false, the reference count obtained by lookup_positive_unlocked() in cachefiles_look_up_object() should be released. Therefore release that reference count in cachefiles_look_up_object() to fix the above issue and simplify the code.
Impacted products

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/cachefiles/namei.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d32ff64c872d7e08e893c32ba6a2374583444410",
              "status": "affected",
              "version": "1f08c925e7a38002bde509e66f6f891468848511",
              "versionType": "git"
            },
            {
              "lessThan": "c7d10fa7d7691558ff967668494672415f5fa151",
              "status": "affected",
              "version": "1f08c925e7a38002bde509e66f6f891468848511",
              "versionType": "git"
            },
            {
              "lessThan": "e4a28489b310339b2b8187bec0a437709be551c1",
              "status": "affected",
              "version": "1f08c925e7a38002bde509e66f6f891468848511",
              "versionType": "git"
            },
            {
              "lessThan": "7fa2382f97421978514a419c93054eca69f5247b",
              "status": "affected",
              "version": "1f08c925e7a38002bde509e66f6f891468848511",
              "versionType": "git"
            },
            {
              "lessThan": "da6ef2dffe6056aad3435e6cf7c6471c2a62187c",
              "status": "affected",
              "version": "1f08c925e7a38002bde509e66f6f891468848511",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/cachefiles/namei.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.17"
            },
            {
              "lessThan": "5.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.55",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.10.*",
              "status": "unaffected",
              "version": "6.10.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.11.*",
              "status": "unaffected",
              "version": "6.11.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.12",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "09358D68-A717-469E-B900-8002A642E29A",
              "versionEndExcluding": "6.1.113",
              "versionStartIncluding": "5.17",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "E90B9576-56C4-47BC-AAB0-C5B2D438F5D0",
              "versionEndExcluding": "6.6.55",
              "versionStartIncluding": "6.2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "4C16BCE0-FFA0-4599-BE0A-1FD65101C021",
              "versionEndExcluding": "6.10.14",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "54D9C704-D679-41A7-9C40-10A6B1E7FFE9",
              "versionEndExcluding": "6.11.3",
              "versionStartIncluding": "6.11",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "7F361E1D-580F-4A2D-A509-7615F73167A1",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncachefiles: fix dentry leak in cachefiles_open_file()\n\nA dentry leak may be caused when a lookup cookie and a cull are concurrent:\n\n            P1             |             P2\n-----------------------------------------------------------\ncachefiles_lookup_cookie\n  cachefiles_look_up_object\n    lookup_one_positive_unlocked\n     // get dentry\n                            cachefiles_cull\n                              inode-\u003ei_flags |= S_KERNEL_FILE;\n    cachefiles_open_file\n      cachefiles_mark_inode_in_use\n        __cachefiles_mark_inode_in_use\n          can_use = false\n          if (!(inode-\u003ei_flags \u0026 S_KERNEL_FILE))\n            can_use = true\n\t  return false\n        return false\n        // Returns an error but doesn\u0027t put dentry\n\nAfter that the following WARNING will be triggered when the backend folder\nis umounted:\n\n==================================================================\nBUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img}  still in use (1) [unmount of ext4 sda]\nWARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70\nCPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25\nRIP: 0010:umount_check+0x5d/0x70\nCall Trace:\n \u003cTASK\u003e\n d_walk+0xda/0x2b0\n do_one_tree+0x20/0x40\n shrink_dcache_for_umount+0x2c/0x90\n generic_shutdown_super+0x20/0x160\n kill_block_super+0x1a/0x40\n ext4_kill_sb+0x22/0x40\n deactivate_locked_super+0x35/0x80\n cleanup_mnt+0x104/0x160\n==================================================================\n\nWhether cachefiles_open_file() returns true or false, the reference count\nobtained by lookup_positive_unlocked() in cachefiles_look_up_object()\nshould be released.\n\nTherefore release that reference count in cachefiles_look_up_object() to\nfix the above issue and simplify the code."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: cachefiles: se corrige la p\u00e9rdida de dentry en cachefiles_open_file(). Una p\u00e9rdida de dentry puede producirse cuando una cookie de b\u00fasqueda y un cull son concurrentes: P1 | P2 ----------------------------------------------------------- cachefiles_lookup_cookie cachefiles_look_up_object lookup_one_positive_unlocked // obtener dentry cachefiles_cull inode-\u0026gt;i_flags |= S_KERNEL_FILE; cachefiles_open_file cachefiles_mark_inode_in_use __cachefiles_mark_inode_in_use can_use = false if (!(inode-\u0026gt;i_flags \u0026amp; S_KERNEL_FILE)) can_use = true return false return false // Devuelve un error pero no coloca dentry Despu\u00e9s de eso, se activar\u00e1 la siguiente ADVERTENCIA cuando se desmonte la carpeta del backend: ===================================================================== ERROR: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img} todav\u00eda en uso (1) [desmontaje de ext4 sda] ADVERTENCIA: CPU: 4 PID: 359261 en fs/dcache.c:1767 umount_check+0x5d/0x70 CPU: 4 PID: 359261 Comm: umount No contaminado 6.6.0-dirty #25 RIP: 0010:umount_check+0x5d/0x70 Rastreo de llamadas:  d_walk+0xda/0x2b0 do_one_tree+0x20/0x40 shrink_dcache_for_umount+0x2c/0x90 generic_shutdown_super+0x20/0x160 kill_block_super+0x1a/0x40 ext4_kill_sb+0x22/0x40 deactivate_locked_super+0x35/0x80 cleanup_mnt+0x104/0x160 ==================================================================== Independientemente de si cachefiles_open_file() devuelve verdadero o falso, el recuento de referencias obtenido por lookup_positive_unlocked() en cachefiles_look_up_object() debe liberarse. Por lo tanto, libere ese recuento de referencias en cachefiles_look_up_object() para solucionar el problema anterior y simplificar el c\u00f3digo."
    }
  ],
  "id": "CVE-2024-49870",
  "lastModified": "2026-06-17T08:00:37.487",
  "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"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2024-49870",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-10-22T13:47:04.248927Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-10-21T18:15:08.413",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/7fa2382f97421978514a419c93054eca69f5247b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c7d10fa7d7691558ff967668494672415f5fa151"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/d32ff64c872d7e08e893c32ba6a2374583444410"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/da6ef2dffe6056aad3435e6cf7c6471c2a62187c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e4a28489b310339b2b8187bec0a437709be551c1"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-401"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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