Vulnerability-Lookup

FKIE_CVE-2026-89645

Vulnerability from fkie_nvd - Published: 2026-09-11 20:19 - Updated: 2026-09-11 20:19

Severity

Summary

In the Linux kernel, the following vulnerability has been resolved: btrfs: drop recovered reloc root refs on recovery failure During relocation recovery, each fs root gets a reference to its relocation root. If loading or adding a later root fails, or if the first transaction commit fails, btrfs_recover_relocation() jumps to out_unset before merge_reloc_roots() and clean_dirty_subvols(). put_reloc_control() drops the list-owned relocation root references, but it does not clear fs_root->reloc_root or drop the references owned by those pointers. Mount cleanup only drops them when BTRFS_FS_ERROR is set, so an error such as -ENOMEM while processing a later root can leave references behind. Keep temporary references to the fs roots associated during recovery. On failure, clear their reloc_root pointers and drop the corresponding references. Once the first transaction commit succeeds, drop only the temporary fs root references and let the normal merge and cleanup paths handle the relocation roots. Fault injection on a pending-relocation image confirmed the cleanup gap. With an injected first-commit failure, 25 fs roots had reloc_root set with fs_error=0. With this fix, the same failure path drops that count to 0 before mount fails.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2256d6dc5b88841a8a8b4fd9a9f04730705fb6fd
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4d43107e807bcd92621106b07f5011411c6341a8
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6d8ba4572922e336f0b59a80751b018e1e135164
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/8a64baeb5bbb706b83d2235c1e39f5b77183817f

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/relocation.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2256d6dc5b88841a8a8b4fd9a9f04730705fb6fd",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            },
            {
              "lessThan": "8a64baeb5bbb706b83d2235c1e39f5b77183817f",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            },
            {
              "lessThan": "4d43107e807bcd92621106b07f5011411c6341a8",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            },
            {
              "lessThan": "6d8ba4572922e336f0b59a80751b018e1e135164",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/relocation.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.7"
            },
            {
              "lessThan": "5.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: drop recovered reloc root refs on recovery failure\n\nDuring relocation recovery, each fs root gets a reference to its relocation\nroot. If loading or adding a later root fails, or if the first transaction\ncommit fails, btrfs_recover_relocation() jumps to out_unset before\nmerge_reloc_roots() and clean_dirty_subvols().\n\nput_reloc_control() drops the list-owned relocation root references, but it\ndoes not clear fs_root-\u003ereloc_root or drop the references owned by those\npointers. Mount cleanup only drops them when BTRFS_FS_ERROR is set, so an\nerror such as -ENOMEM while processing a later root can leave references\nbehind.\n\nKeep temporary references to the fs roots associated during recovery. On\nfailure, clear their reloc_root pointers and drop the corresponding\nreferences. Once the first transaction commit succeeds, drop only the\ntemporary fs root references and let the normal merge and cleanup paths\nhandle the relocation roots.\n\nFault injection on a pending-relocation image confirmed the cleanup gap.\nWith an injected first-commit failure, 25 fs roots had reloc_root set with\nfs_error=0. With this fix, the same failure path drops that count to 0\nbefore mount fails."
    }
  ],
  "id": "CVE-2026-89645",
  "lastModified": "2026-09-11T20:19:50.350",
  "metrics": {},
  "published": "2026-09-11T20:19:50.350",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/2256d6dc5b88841a8a8b4fd9a9f04730705fb6fd"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4d43107e807bcd92621106b07f5011411c6341a8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6d8ba4572922e336f0b59a80751b018e1e135164"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8a64baeb5bbb706b83d2235c1e39f5b77183817f"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-89645 (GCVE-0-2026-89645)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:45 – Updated: 2026-09-11 19:45

Title

btrfs: drop recovered reloc root refs on recovery failure

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/2256d6dc5b88841a8…
https://git.kernel.org/stable/c/8a64baeb5bbb706b8…
https://git.kernel.org/stable/c/4d43107e807bcd926…
https://git.kernel.org/stable/c/6d8ba4572922e336f…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: f44deb7442edf42abee6be25fca7e3e86061b4c9 , < 2256d6dc5b88841a8a8b4fd9a9f04730705fb6fd (git) Affected: f44deb7442edf42abee6be25fca7e3e86061b4c9 , < 8a64baeb5bbb706b83d2235c1e39f5b77183817f (git) Affected: f44deb7442edf42abee6be25fca7e3e86061b4c9 , < 4d43107e807bcd92621106b07f5011411c6341a8 (git) Affected: f44deb7442edf42abee6be25fca7e3e86061b4c9 , < 6d8ba4572922e336f0b59a80751b018e1e135164 (git)
Linux	Linux	Affected: 5.7 Unaffected: 0 , < 5.7 (semver) Unaffected: 6.12.109 , ≤ 6.12.* (semver) Unaffected: 6.18.50 , ≤ 6.18.* (semver) Unaffected: 7.2.4 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/relocation.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2256d6dc5b88841a8a8b4fd9a9f04730705fb6fd",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            },
            {
              "lessThan": "8a64baeb5bbb706b83d2235c1e39f5b77183817f",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            },
            {
              "lessThan": "4d43107e807bcd92621106b07f5011411c6341a8",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            },
            {
              "lessThan": "6d8ba4572922e336f0b59a80751b018e1e135164",
              "status": "affected",
              "version": "f44deb7442edf42abee6be25fca7e3e86061b4c9",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/relocation.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.7"
            },
            {
              "lessThan": "5.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.109",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.50",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: drop recovered reloc root refs on recovery failure\n\nDuring relocation recovery, each fs root gets a reference to its relocation\nroot. If loading or adding a later root fails, or if the first transaction\ncommit fails, btrfs_recover_relocation() jumps to out_unset before\nmerge_reloc_roots() and clean_dirty_subvols().\n\nput_reloc_control() drops the list-owned relocation root references, but it\ndoes not clear fs_root-\u003ereloc_root or drop the references owned by those\npointers. Mount cleanup only drops them when BTRFS_FS_ERROR is set, so an\nerror such as -ENOMEM while processing a later root can leave references\nbehind.\n\nKeep temporary references to the fs roots associated during recovery. On\nfailure, clear their reloc_root pointers and drop the corresponding\nreferences. Once the first transaction commit succeeds, drop only the\ntemporary fs root references and let the normal merge and cleanup paths\nhandle the relocation roots.\n\nFault injection on a pending-relocation image confirmed the cleanup gap.\nWith an injected first-commit failure, 25 fs roots had reloc_root set with\nfs_error=0. With this fix, the same failure path drops that count to 0\nbefore mount fails."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-11T19:45:37.016Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2256d6dc5b88841a8a8b4fd9a9f04730705fb6fd"
        },
        {
          "url": "https://git.kernel.org/stable/c/8a64baeb5bbb706b83d2235c1e39f5b77183817f"
        },
        {
          "url": "https://git.kernel.org/stable/c/4d43107e807bcd92621106b07f5011411c6341a8"
        },
        {
          "url": "https://git.kernel.org/stable/c/6d8ba4572922e336f0b59a80751b018e1e135164"
        }
      ],
      "title": "btrfs: drop recovered reloc root refs on recovery failure",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89645",
    "datePublished": "2026-09-11T19:45:37.016Z",
    "dateReserved": "2026-09-11T19:38:34.741Z",
    "dateUpdated": "2026-09-11T19:45:37.016Z",
    "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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.