Vulnerability-Lookup

GHSA-6P99-W6F4-QCVQ

Vulnerability from github – Published: 2026-07-23 06:32 – Updated: 2026-07-23 09:31

Details

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

xfs: resample the data fork mapping after cycling ILOCK

xfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode, a data fork mapping, and a cow fork mapping. Unfortunately, these two helpers cycle the ILOCK to grab a transaction, which means that the mappings are stale as soon as we reacquire the ILOCK. Currently we refresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but we don't refresh the data fork mapping beforehand, which means that the xfs_bmap_trim_cow in that function queries the refcount btree about the wrong physical blocks and returns an inaccurate value in *shared.

If *shared is now false, the directio write proceeds with a stale data fork mapping. Fix this by querying the data fork mapping if the sequence counter changes across the ILOCK cycle.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-64600"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-23T06:16:50Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: resample the data fork mapping after cycling ILOCK\n\nxfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode,\na data fork mapping, and a cow fork mapping.  Unfortunately, these two\nhelpers cycle the ILOCK to grab a transaction, which means that the\nmappings are stale as soon as we reacquire the ILOCK.  Currently we\nrefresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but\nwe don\u0027t refresh the data fork mapping beforehand, which means that the\nxfs_bmap_trim_cow in that function queries the refcount btree about the\nwrong physical blocks and returns an inaccurate value in *shared.\n\nIf *shared is now false, the directio write proceeds with a stale data\nfork mapping.  Fix this by querying the data fork mapping if the\nsequence counter changes across the ILOCK cycle.",
  "id": "GHSA-6p99-w6f4-qcvq",
  "modified": "2026-07-23T09:31:59Z",
  "published": "2026-07-23T06:32:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64600"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/206c09b04dc5469c7ff14d8aceff2d47c88078d9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f4acd0fcd862e22eab45690ec2c08c80b6ef2e7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/44f891bc088958399eec27f7604928694aa35581"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e705d81a7193dd19e69b8e2bad4696d78a4ea075"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/07/22/14"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/07/22/18"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/07/22/19"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-64600 (GCVE-0-2026-64600)

Vulnerability from cvelistv5 – Published: 2026-07-23 05:46 – Updated: 2026-07-23 06:54

Title

xfs: resample the data fork mapping after cycling ILOCK

Summary

In the Linux kernel, the following vulnerability has been resolved: xfs: resample the data fork mapping after cycling ILOCK xfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode, a data fork mapping, and a cow fork mapping. Unfortunately, these two helpers cycle the ILOCK to grab a transaction, which means that the mappings are stale as soon as we reacquire the ILOCK. Currently we refresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but we don't refresh the data fork mapping beforehand, which means that the xfs_bmap_trim_cow in that function queries the refcount btree about the wrong physical blocks and returns an inaccurate value in *shared. If *shared is now false, the directio write proceeds with a stale data fork mapping. Fix this by querying the data fork mapping if the sequence counter changes across the ILOCK cycle.

Severity

No CVSS data available.

Assigner

Linux

References

7 references

URL	Tags
https://git.kernel.org/stable/c/e705d81a7193dd19e…
https://git.kernel.org/stable/c/206c09b04dc5469c7…
https://git.kernel.org/stable/c/44f891bc088958399…
https://git.kernel.org/stable/c/2f4acd0fcd862e22e…
http://www.openwall.com/lists/oss-security/2026/0…
http://www.openwall.com/lists/oss-security/2026/0…
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 , < e705d81a7193dd19e69b8e2bad4696d78a4ea075 (git) Affected: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 , < 206c09b04dc5469c7ff14d8aceff2d47c88078d9 (git) Affected: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 , < 44f891bc088958399eec27f7604928694aa35581 (git) Affected: 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 , < 2f4acd0fcd862e22eab45690ec2c08c80b6ef2e7 (git)
Linux	Linux	Affected: 4.11 Unaffected: 0 , < 4.11 (semver) Unaffected: 6.12.96 , ≤ 6.12.* (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2-rc4 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-07-23T06:54:07.428Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/07/22/14"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/07/22/18"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/07/22/19"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/xfs/xfs_reflink.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e705d81a7193dd19e69b8e2bad4696d78a4ea075",
              "status": "affected",
              "version": "3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5",
              "versionType": "git"
            },
            {
              "lessThan": "206c09b04dc5469c7ff14d8aceff2d47c88078d9",
              "status": "affected",
              "version": "3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5",
              "versionType": "git"
            },
            {
              "lessThan": "44f891bc088958399eec27f7604928694aa35581",
              "status": "affected",
              "version": "3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5",
              "versionType": "git"
            },
            {
              "lessThan": "2f4acd0fcd862e22eab45690ec2c08c80b6ef2e7",
              "status": "affected",
              "version": "3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/xfs/xfs_reflink.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.11"
            },
            {
              "lessThan": "4.11",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.96",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.39",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2-rc4",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.96",
                  "versionStartIncluding": "4.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.39",
                  "versionStartIncluding": "4.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.4",
                  "versionStartIncluding": "4.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2-rc4",
                  "versionStartIncluding": "4.11",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: resample the data fork mapping after cycling ILOCK\n\nxfs_reflink_fill_{cow_hole,delalloc} are both presented with an inode,\na data fork mapping, and a cow fork mapping.  Unfortunately, these two\nhelpers cycle the ILOCK to grab a transaction, which means that the\nmappings are stale as soon as we reacquire the ILOCK.  Currently we\nrefresh the cow fork mapping by re-calling xfs_find_trim_cow_extent, but\nwe don\u0027t refresh the data fork mapping beforehand, which means that the\nxfs_bmap_trim_cow in that function queries the refcount btree about the\nwrong physical blocks and returns an inaccurate value in *shared.\n\nIf *shared is now false, the directio write proceeds with a stale data\nfork mapping.  Fix this by querying the data fork mapping if the\nsequence counter changes across the ILOCK cycle."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-23T05:47:18.646Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/e705d81a7193dd19e69b8e2bad4696d78a4ea075"
        },
        {
          "url": "https://git.kernel.org/stable/c/206c09b04dc5469c7ff14d8aceff2d47c88078d9"
        },
        {
          "url": "https://git.kernel.org/stable/c/44f891bc088958399eec27f7604928694aa35581"
        },
        {
          "url": "https://git.kernel.org/stable/c/2f4acd0fcd862e22eab45690ec2c08c80b6ef2e7"
        }
      ],
      "title": "xfs: resample the data fork mapping after cycling ILOCK",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64600",
    "datePublished": "2026-07-23T05:46:56.149Z",
    "dateReserved": "2026-07-19T15:36:31.799Z",
    "dateUpdated": "2026-07-23T06:54:07.428Z",
    "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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-6P99-W6F4-QCVQ

CVE-2026-64600 (GCVE-0-2026-64600)

Tags

Sightings

Nomenclature