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FKIE_CVE-2021-47507

Vulnerability from fkie_nvd - Published: 2024-05-24 15:15 - Updated: 2026-06-17 04:17
Severity
4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: Fix nsfd startup race (again) Commit bd5ae9288d64 ("nfsd: register pernet ops last, unregister first") has re-opened rpc_pipefs_event() race against nfsd_net_id registration (register_pernet_subsys()) which has been fixed by commit bb7ffbf29e76 ("nfsd: fix nsfd startup race triggering BUG_ON"). Restore the order of register_pernet_subsys() vs register_cld_notifier(). Add WARN_ON() to prevent a future regression. Crash info: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000012 CPU: 8 PID: 345 Comm: mount Not tainted 5.4.144-... #1 pc : rpc_pipefs_event+0x54/0x120 [nfsd] lr : rpc_pipefs_event+0x48/0x120 [nfsd] Call trace: rpc_pipefs_event+0x54/0x120 [nfsd] blocking_notifier_call_chain rpc_fill_super get_tree_keyed rpc_fs_get_tree vfs_get_tree do_mount ksys_mount __arm64_sys_mount el0_svc_handler el0_svc
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8bf902fee5893cfc2f04a698abab47629699ae9aPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b10252c7ae9c9d7c90552f88b544a44ee773af64Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c520943a00ad5015704969ad3304c956bcd49d25Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f5734b1714ca355703e9ea8fb61d04beff1790b9Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/8bf902fee5893cfc2f04a698abab47629699ae9aPatch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/b10252c7ae9c9d7c90552f88b544a44ee773af64Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/c520943a00ad5015704969ad3304c956bcd49d25Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/f5734b1714ca355703e9ea8fb61d04beff1790b9Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 5.16
linux linux_kernel 5.16
linux linux_kernel 5.16
linux linux_kernel 5.16
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4recover.c",
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "f5734b1714ca355703e9ea8fb61d04beff1790b9",
              "status": "affected",
              "version": "8677e99150b0830d29cc1318b4cc559e176940bb",
              "versionType": "git"
            },
            {
              "lessThan": "c520943a00ad5015704969ad3304c956bcd49d25",
              "status": "affected",
              "version": "7c7cb07d4affcf41749234fe9dc4d90cd3959e32",
              "versionType": "git"
            },
            {
              "lessThan": "8bf902fee5893cfc2f04a698abab47629699ae9a",
              "status": "affected",
              "version": "bd5ae9288d6451bd346a1b4a59d4fe7e62ba29b7",
              "versionType": "git"
            },
            {
              "lessThan": "b10252c7ae9c9d7c90552f88b544a44ee773af64",
              "status": "affected",
              "version": "bd5ae9288d6451bd346a1b4a59d4fe7e62ba29b7",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4d41f65efeec0a6da6088341203c81e49ebfcd90",
              "versionType": "git"
            },
            {
              "lessThan": "5.4.165",
              "status": "affected",
              "version": "5.4.102",
              "versionType": "semver"
            },
            {
              "lessThan": "5.10.85",
              "status": "affected",
              "version": "5.10.20",
              "versionType": "semver"
            },
            {
              "lessThan": "5.12",
              "status": "affected",
              "version": "5.11.3",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4recover.c",
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.12"
            },
            {
              "lessThan": "5.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.165",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.85",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.16",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "A0D5C567-7B87-43EE-B0FC-159293C8978C",
              "versionEndExcluding": "5.4.165",
              "versionStartIncluding": "5.4.102",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "75AD2AC7-1AA4-43FD-98B8-DE29CB66448E",
              "versionEndExcluding": "5.10.85",
              "versionStartIncluding": "5.10.20",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "C681853B-53AB-42A9-B5BC-153C89266864",
              "versionEndExcluding": "5.15.8",
              "versionStartIncluding": "5.11.3",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "357AA433-37E8-4323-BFB2-3038D6E4B414",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "A73429BA-C2D9-4D0C-A75F-06A1CA8B3983",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "F621B5E3-E99D-49E7-90B9-EC3B77C95383",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "F7BFDCAA-1650-49AA-8462-407DD593F94F",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: Fix nsfd startup race (again)\n\nCommit bd5ae9288d64 (\"nfsd: register pernet ops last, unregister first\")\nhas re-opened rpc_pipefs_event() race against nfsd_net_id registration\n(register_pernet_subsys()) which has been fixed by commit bb7ffbf29e76\n(\"nfsd: fix nsfd startup race triggering BUG_ON\").\n\nRestore the order of register_pernet_subsys() vs register_cld_notifier().\nAdd WARN_ON() to prevent a future regression.\n\nCrash info:\nUnable to handle kernel NULL pointer dereference at virtual address 0000000000000012\nCPU: 8 PID: 345 Comm: mount Not tainted 5.4.144-... #1\npc : rpc_pipefs_event+0x54/0x120 [nfsd]\nlr : rpc_pipefs_event+0x48/0x120 [nfsd]\nCall trace:\n rpc_pipefs_event+0x54/0x120 [nfsd]\n blocking_notifier_call_chain\n rpc_fill_super\n get_tree_keyed\n rpc_fs_get_tree\n vfs_get_tree\n do_mount\n ksys_mount\n __arm64_sys_mount\n el0_svc_handler\n el0_svc"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: nfsd: corrige la ejecuci\u00f3n de inicio de nsfd (nuevamente) El commit bd5ae9288d64 (\"nfsd: registre las operaciones de pernet al final, anule el registro primero\") ha reabierto la ejecuci\u00f3n de rpc_pipefs_event() contra el registro de nfsd_net_id (register_pernet_subsys( )) que se ha solucionado mediante el commit bb7ffbf29e76 (\"nfsd: arreglar la ejecuci\u00f3n de inicio de nsfd que activa BUG_ON\"). Restaure el orden de Register_pernet_subsys() frente a Register_cld_notifier(). Agregue WARN_ON() para evitar una regresi\u00f3n futura. Informaci\u00f3n de falla: no se puede manejar la desreferencia del puntero NULL del kernel en la direcci\u00f3n virtual 0000000000000012 CPU: 8 PID: 345 Comm: mount Not tainted 5.4.144-... #1 pc: rpc_pipefs_event+0x54/0x120 [nfsd] lr: rpc_pipefs_event+0x48/ 0x120 [nfsd] Rastreo de llamadas: rpc_pipefs_event+0x54/0x120 [nfsd] blocking_notifier_call_chain rpc_fill_super get_tree_keyed rpc_fs_get_tree vfs_get_tree do_mount ksys_mount __arm64_sys_mount el0_svc_handler el0_svc"
    }
  ],
  "id": "CVE-2021-47507",
  "lastModified": "2026-06-17T04:17:39.120",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 4.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47507",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-09-10T15:35:42.793649Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-05-24T15:15:11.400",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/8bf902fee5893cfc2f04a698abab47629699ae9a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/b10252c7ae9c9d7c90552f88b544a44ee773af64"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c520943a00ad5015704969ad3304c956bcd49d25"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/f5734b1714ca355703e9ea8fb61d04beff1790b9"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/8bf902fee5893cfc2f04a698abab47629699ae9a"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/b10252c7ae9c9d7c90552f88b544a44ee773af64"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c520943a00ad5015704969ad3304c956bcd49d25"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/f5734b1714ca355703e9ea8fb61d04beff1790b9"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-362"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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