{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B263F4AD-C03D-4E6A-995E-B822989C3A7A",
              "versionEndExcluding": "6.18.6",
              "versionStartIncluding": "6.18",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix use-after-free warning in btrfs_get_or_create_delayed_node()\n\nPreviously, btrfs_get_or_create_delayed_node() set the delayed_node\u0027s\nrefcount before acquiring the root-\u003edelayed_nodes lock.\nCommit e8513c012de7 (\"btrfs: implement ref_tracker for delayed_nodes\")\nmoved refcount_set inside the critical section, which means there is\nno longer a memory barrier between setting the refcount and setting\nbtrfs_inode-\u003edelayed_node.\n\nWithout that barrier, the stores to node-\u003erefs and\nbtrfs_inode-\u003edelayed_node may become visible out of order. Another\nthread can then read btrfs_inode-\u003edelayed_node and attempt to\nincrement a refcount that hasn\u0027t been set yet, leading to a\nrefcounting bug and a use-after-free warning.\n\nThe fix is to move refcount_set back to where it was to take\nadvantage of the implicit memory barrier provided by lock\nacquisition.\n\nBecause the allocations now happen outside of the lock\u0027s critical\nsection, they can use GFP_NOFS instead of GFP_ATOMIC."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nbtrfs: soluciona la advertencia de uso despu\u00e9s de liberaci\u00f3n en btrfs_get_or_create_delayed_node()\n\nAnteriormente, btrfs_get_or_create_delayed_node() establec\u00eda el refcount del delayed_node antes de adquirir el bloqueo root-\u0026gt;delayed_nodes. El commit e8513c012de7 (\u0027btrfs: implementa ref_tracker para delayed_nodes\u0027) movi\u00f3 refcount_set dentro de la secci\u00f3n cr\u00edtica, lo que significa que ya no hay una barrera de memoria entre el establecimiento del refcount y el establecimiento de btrfs_inode-\u0026gt;delayed_node.\n\nSin esa barrera, los almacenamientos en node-\u0026gt;refs y btrfs_inode-\u0026gt;delayed_node pueden volverse visibles fuera de orden. Otro hilo puede entonces leer btrfs_inode-\u0026gt;delayed_node e intentar incrementar un refcount que a\u00fan no ha sido establecido, lo que lleva a un error de refcounting y a una advertencia de uso despu\u00e9s de liberaci\u00f3n.\n\nLa soluci\u00f3n es mover refcount_set de vuelta a donde estaba para aprovechar la barrera de memoria impl\u00edcita proporcionada por la adquisici\u00f3n del bloqueo.\n\nDebido a que las asignaciones ahora ocurren fuera de la secci\u00f3n cr\u00edtica del bloqueo, pueden usar GFP_NOFS en lugar de GFP_ATOMIC."
    }
  ],
  "id": "CVE-2025-71159",
  "lastModified": "2026-02-26T20:19:48.380",
  "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": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-01-23T16:15:52.793",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/83f59076a1ae6f5c6845d6f7ed3a1a373d883684"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/c8385851a5435f4006281828d428e5d0b0bbf8af"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}