Vulnerability-Lookup

GHSA-C5QQ-QCR6-82VP

Vulnerability from github – Published: 2024-05-21 15:31 – Updated: 2024-12-26 21:30

Details

In the Linux kernel, the following vulnerability has been resolved:

ext4: fix possible UAF when remounting r/o a mmp-protected file system

After commit 618f003199c6 ("ext4: fix memory leak in ext4_fill_super"), after the file system is remounted read-only, there is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to point at freed memory, which the call to ext4_stop_mmpd() can trip over.

Fix this by only allowing kmmpd() to exit when it is stopped via ext4_stop_mmpd().

Bug-Report-Link: 20210629143603.2166962-1-yebin10@huawei.com

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2021-47342"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-21T15:15:20Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix possible UAF when remounting r/o a mmp-protected file system\n\nAfter commit 618f003199c6 (\"ext4: fix memory leak in\next4_fill_super\"), after the file system is remounted read-only, there\nis a race where the kmmpd thread can exit, causing sbi-\u003es_mmp_tsk to\npoint at freed memory, which the call to ext4_stop_mmpd() can trip\nover.\n\nFix this by only allowing kmmpd() to exit when it is stopped via\next4_stop_mmpd().\n\nBug-Report-Link: \u003c20210629143603.2166962-1-yebin10@huawei.com\u003e",
  "id": "GHSA-c5qq-qcr6-82vp",
  "modified": "2024-12-26T21:30:36Z",
  "published": "2024-05-21T15:31:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47342"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/61bb4a1c417e5b95d9edb4f887f131de32e419cb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b663890d854403e566169f7e90aed5cd6ff64f6b"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2021-47342 (GCVE-0-2021-47342)

Vulnerability from cvelistv5 – Published: 2024-05-21 14:35 – Updated: 2026-05-23 15:19

Title

ext4: fix possible UAF when remounting r/o a mmp-protected file system

Summary

In the Linux kernel, the following vulnerability has been resolved: ext4: fix possible UAF when remounting r/o a mmp-protected file system After commit 618f003199c6 ("ext4: fix memory leak in ext4_fill_super"), after the file system is remounted read-only, there is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to point at freed memory, which the call to ext4_stop_mmpd() can trip over. Fix this by only allowing kmmpd() to exit when it is stopped via ext4_stop_mmpd(). Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com>

Severity

No CVSS data available.

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/b663890d854403e56…
https://git.kernel.org/stable/c/7ed572cdf11081f8f…
https://git.kernel.org/stable/c/61bb4a1c417e5b95d…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 5e4f5138bd8522ebe231a137682d3857209a2c07 , < b663890d854403e566169f7e90aed5cd6ff64f6b (git) Affected: eb7b40d9d3785f7a131fb0b1f89bb6efa46c1833 , < 7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd (git) Affected: 618f003199c6188e01472b03cdbba227f1dc5f24 , < 61bb4a1c417e5b95d9edb4f887f131de32e419cb (git) Affected: cecfdb9cf9a700d1037066173abac0617f6788df (git) Affected: 5.12.18 , < 5.13 (semver)
Linux	Linux	Affected: 5.10.51 , < 5.10.77 (semver)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47342",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-05-28T18:31:24.504163Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-06-04T17:15:04.055Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T05:32:08.518Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/b663890d854403e566169f7e90aed5cd6ff64f6b"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/61bb4a1c417e5b95d9edb4f887f131de32e419cb"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ext4/mmp.c",
            "fs/ext4/super.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b663890d854403e566169f7e90aed5cd6ff64f6b",
              "status": "affected",
              "version": "5e4f5138bd8522ebe231a137682d3857209a2c07",
              "versionType": "git"
            },
            {
              "lessThan": "7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd",
              "status": "affected",
              "version": "eb7b40d9d3785f7a131fb0b1f89bb6efa46c1833",
              "versionType": "git"
            },
            {
              "lessThan": "61bb4a1c417e5b95d9edb4f887f131de32e419cb",
              "status": "affected",
              "version": "618f003199c6188e01472b03cdbba227f1dc5f24",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "cecfdb9cf9a700d1037066173abac0617f6788df",
              "versionType": "git"
            },
            {
              "lessThan": "5.13",
              "status": "affected",
              "version": "5.12.18",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ext4/mmp.c",
            "fs/ext4/super.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5.10.77",
              "status": "affected",
              "version": "5.10.51",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.77",
                  "versionStartIncluding": "5.10.51",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.12.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix possible UAF when remounting r/o a mmp-protected file system\n\nAfter commit 618f003199c6 (\"ext4: fix memory leak in\next4_fill_super\"), after the file system is remounted read-only, there\nis a race where the kmmpd thread can exit, causing sbi-\u003es_mmp_tsk to\npoint at freed memory, which the call to ext4_stop_mmpd() can trip\nover.\n\nFix this by only allowing kmmpd() to exit when it is stopped via\next4_stop_mmpd().\n\nBug-Report-Link: \u003c20210629143603.2166962-1-yebin10@huawei.com\u003e"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T15:19:46.440Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b663890d854403e566169f7e90aed5cd6ff64f6b"
        },
        {
          "url": "https://git.kernel.org/stable/c/7ed572cdf11081f8f9e07abd4bea56a3f2c4edbd"
        },
        {
          "url": "https://git.kernel.org/stable/c/61bb4a1c417e5b95d9edb4f887f131de32e419cb"
        }
      ],
      "title": "ext4: fix possible UAF when remounting r/o a mmp-protected file system",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47342",
    "datePublished": "2024-05-21T14:35:49.643Z",
    "dateReserved": "2024-05-21T14:28:16.979Z",
    "dateUpdated": "2026-05-23T15:19:46.440Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-C5QQ-QCR6-82VP

CVE-2021-47342 (GCVE-0-2021-47342)

Tags

Sightings

Nomenclature