FKIE_CVE-2021-47638

Vulnerability from fkie_nvd - Published: 2025-02-26 06:37 - Updated: 2026-08-04 10:17
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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: ubifs: rename_whiteout: Fix double free for whiteout_ui->data 'whiteout_ui->data' will be freed twice if space budget fail for rename whiteout operation as following process: rename_whiteout dev = kmalloc whiteout_ui->data = dev kfree(whiteout_ui->data) // Free first time iput(whiteout) ubifs_free_inode kfree(ui->data) // Double free! KASAN reports: ================================================================== BUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70 Call Trace: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f Allocated by task 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 Freed by task 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8 ================================================================== Let ubifs_free_inode() free 'whiteout_ui->data'. BTW, delete unused assignment 'whiteout_ui->data_len = 0', process 'ubifs_evict_inode() -> ubifs_jnl_delete_inode() -> ubifs_jnl_write_inode()' doesn't need it (because 'inc_nlink(whiteout)' won't be excuted by 'goto out_release', and the nlink of whiteout inode is 0).
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/14276d38c89a170363e90b6ac0a53c3cf61b87fcPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2ad07009c459e56ebdcc089d850d664660fdb742Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2b3236ecf96db7af5836e1366ce39ace8ce832faPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/40a8f0d5e7b3999f096570edab71c345da812e3ePatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6d7a158a7363c1f6604aa47ae1a280a5c65123ddPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8b3c7be16f3f4dfd6e15ac651484e59d3fa36274Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a90e2dbe66d2647ff95a0442ad2e86482d977fd8Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b9a937f096e608b3368c1abc920d4d640ba2c94fPatch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ubifs/dir.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8b3c7be16f3f4dfd6e15ac651484e59d3fa36274",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "2b3236ecf96db7af5836e1366ce39ace8ce832fa",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "14276d38c89a170363e90b6ac0a53c3cf61b87fc",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "a90e2dbe66d2647ff95a0442ad2e86482d977fd8",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "2ad07009c459e56ebdcc089d850d664660fdb742",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "b9a937f096e608b3368c1abc920d4d640ba2c94f",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "6d7a158a7363c1f6604aa47ae1a280a5c65123dd",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            },
            {
              "lessThan": "40a8f0d5e7b3999f096570edab71c345da812e3e",
              "status": "affected",
              "version": "9e0a1fff8db56eaaebb74b4a3ef65f86811c4798",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ubifs/dir.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.9"
            },
            {
              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.14.*",
              "status": "unaffected",
              "version": "4.14.276",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.19.*",
              "status": "unaffected",
              "version": "4.19.238",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.189",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.110",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.33",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.16.*",
              "status": "unaffected",
              "version": "5.16.19",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.17.*",
              "status": "unaffected",
              "version": "5.17.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "EA8D1234-835A-47E7-8014-55948757E778",
              "versionEndExcluding": "4.14.276",
              "versionStartIncluding": "4.9",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "FA28527A-11D3-41D2-9C4C-ECAC0D6A4A2D",
              "versionEndExcluding": "4.19.238",
              "versionStartIncluding": "4.15",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8CB6E8F5-C2B1-46F3-A807-0F6104AC340F",
              "versionEndExcluding": "5.4.189",
              "versionStartIncluding": "4.20",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "91D3BFD0-D3F3-4018-957C-96CCBF357D79",
              "versionEndExcluding": "5.10.110",
              "versionStartIncluding": "5.5",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "27C42AE8-B387-43E2-938A-E1C8B40BE6D5",
              "versionEndExcluding": "5.15.33",
              "versionStartIncluding": "5.11",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "20C43679-0439-405A-B97F-685BEE50613B",
              "versionEndExcluding": "5.16.19",
              "versionStartIncluding": "5.16",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "210C679C-CF84-44A3-8939-E629C87E54BF",
              "versionEndExcluding": "5.17.2",
              "versionStartIncluding": "5.17",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nubifs: rename_whiteout: Fix double free for whiteout_ui-\u003edata\n\n\u0027whiteout_ui-\u003edata\u0027 will be freed twice if space budget fail for\nrename whiteout operation as following process:\n\nrename_whiteout\n  dev = kmalloc\n  whiteout_ui-\u003edata = dev\n  kfree(whiteout_ui-\u003edata)  // Free first time\n  iput(whiteout)\n    ubifs_free_inode\n      kfree(ui-\u003edata)\t    // Double free!\n\nKASAN reports:\n==================================================================\nBUG: KASAN: double-free or invalid-free in ubifs_free_inode+0x4f/0x70\nCall Trace:\n  kfree+0x117/0x490\n  ubifs_free_inode+0x4f/0x70 [ubifs]\n  i_callback+0x30/0x60\n  rcu_do_batch+0x366/0xac0\n  __do_softirq+0x133/0x57f\n\nAllocated by task 1506:\n  kmem_cache_alloc_trace+0x3c2/0x7a0\n  do_rename+0x9b7/0x1150 [ubifs]\n  ubifs_rename+0x106/0x1f0 [ubifs]\n  do_syscall_64+0x35/0x80\n\nFreed by task 1506:\n  kfree+0x117/0x490\n  do_rename.cold+0x53/0x8a [ubifs]\n  ubifs_rename+0x106/0x1f0 [ubifs]\n  do_syscall_64+0x35/0x80\n\nThe buggy address belongs to the object at ffff88810238bed8 which\nbelongs to the cache kmalloc-8 of size 8\n==================================================================\n\nLet ubifs_free_inode() free \u0027whiteout_ui-\u003edata\u0027. BTW, delete unused\nassignment \u0027whiteout_ui-\u003edata_len = 0\u0027, process \u0027ubifs_evict_inode()\n-\u003e ubifs_jnl_delete_inode() -\u003e ubifs_jnl_write_inode()\u0027 doesn\u0027t need it\n(because \u0027inc_nlink(whiteout)\u0027 won\u0027t be excuted by \u0027goto out_release\u0027,\n and the nlink of whiteout inode is 0)."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ubifs: rename_whiteout: Se corrige la doble liberaci\u00f3n para whiteout_ui-\u0026gt;data \u0027whiteout_ui-\u0026gt;data\u0027 se liberar\u00e1 dos veces si el presupuesto de espacio falla para la operaci\u00f3n de cambio de nombre de whiteout como el siguiente proceso: rename_whiteout dev = kmalloc whiteout_ui-\u0026gt;data = dev kfree(whiteout_ui-\u0026gt;data) // Libera la primera vez iput(whiteout) ubifs_free_inode kfree(ui-\u0026gt;data) // \u00a1Doble liberaci\u00f3n! KASAN informa: ==================================================================== ERROR: KASAN: liberaci\u00f3n doble o liberaci\u00f3n no v\u00e1lida en ubifs_free_inode+0x4f/0x70 Seguimiento de llamadas: kfree+0x117/0x490 ubifs_free_inode+0x4f/0x70 [ubifs] i_callback+0x30/0x60 rcu_do_batch+0x366/0xac0 __do_softirq+0x133/0x57f Asignado por la tarea 1506: kmem_cache_alloc_trace+0x3c2/0x7a0 do_rename+0x9b7/0x1150 [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 Liberado por la tarea 1506: kfree+0x117/0x490 do_rename.cold+0x53/0x8a [ubifs] ubifs_rename+0x106/0x1f0 [ubifs] do_syscall_64+0x35/0x80 La direcci\u00f3n con errores pertenece al objeto en ffff88810238bed8 que pertenece al cach\u00e9 kmalloc-8 de tama\u00f1o 8 ===================================================================== Deje que ubifs_free_inode() libere \u0027whiteout_ui-\u0026gt;data\u0027. Por cierto, elimine la asignaci\u00f3n no utilizada \u0027whiteout_ui-\u0026gt;data_len = 0\u0027, el proceso \u0027ubifs_evict_inode() -\u0026gt; ubifs_jnl_delete_inode() -\u0026gt; ubifs_jnl_write_inode()\u0027 no lo necesita (porque \u0027inc_nlink(whiteout)\u0027 no ser\u00e1 ejecutado por \u0027goto out_release\u0027, y el nlink del inodo whiteout es 0)."
    }
  ],
  "id": "CVE-2021-47638",
  "lastModified": "2026-08-04T10:17:11.823",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      },
      {
        "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"
      },
      {
        "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": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-47638",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-10-01T19:50:47.905064Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-02-26T06:37:05.580",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/14276d38c89a170363e90b6ac0a53c3cf61b87fc"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/2ad07009c459e56ebdcc089d850d664660fdb742"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/2b3236ecf96db7af5836e1366ce39ace8ce832fa"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/40a8f0d5e7b3999f096570edab71c345da812e3e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/6d7a158a7363c1f6604aa47ae1a280a5c65123dd"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/8b3c7be16f3f4dfd6e15ac651484e59d3fa36274"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/a90e2dbe66d2647ff95a0442ad2e86482d977fd8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/b9a937f096e608b3368c1abc920d4d640ba2c94f"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-415"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-415"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.