{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "c20097329d2c196b818c4666c7820c1378d69d61"
            },
            {
              "fixed": "45c08a752982116f3287afcd1bd9c50f4fab0c28"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "106331a12b0fa5afa6995b1f9ebb03ddcaac6915"
            },
            {
              "fixed": "0b778361998d6c6356b8d2fc7ddf025fb3224654"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "fb70bf124b051d4ded4ce57511dfec6d3ebf2b43"
            },
            {
              "fixed": "973acfdfe90c8a4e58ade97ff0653a498531ff2e"
            },
            {
              "fixed": "0b3a551fa58b4da941efeb209b3770868e2eddd7"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.19.0"
            },
            {
              "fixed": "6.1.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52909.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix handling of cached open files in nfsd4_open codepath\n\nCommit fb70bf124b05 (\"NFSD: Instantiate a struct file when creating a\nregular NFSv4 file\") added the ability to cache an open fd over a\ncompound. There are a couple of problems with the way this currently\nworks:\n\nIt's racy, as a newly-created nfsd_file can end up with its PENDING bit\ncleared while the nf is hashed, and the nf_file pointer is still zeroed\nout. Other tasks can find it in this state and they expect to see a\nvalid nf_file, and can oops if nf_file is NULL.\n\nAlso, there is no guarantee that we'll end up creating a new nfsd_file\nif one is already in the hash. If an extant entry is in the hash with a\nvalid nf_file, nfs4_get_vfs_file will clobber its nf_file pointer with\nthe value of op_file and the old nf_file will leak.\n\nFix both issues by making a new nfsd_file_acquirei_opened variant that\ntakes an optional file pointer. If one is present when this is called,\nwe'll take a new reference to it instead of trying to open the file. If\nthe nfsd_file already has a valid nf_file, we'll just ignore the\noptional file and pass the nfsd_file back as-is.\n\nAlso rework the tracepoints a bit to allow for an \"opened\" variant and\ndon't try to avoid counting acquisitions in the case where we already\nhave a cached open file.",
  "id": "CVE-2023-52909",
  "modified": "2026-07-15T01:49:08.143911477Z",
  "published": "2024-08-21T06:10:50.303Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0b3a551fa58b4da941efeb209b3770868e2eddd7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0b778361998d6c6356b8d2fc7ddf025fb3224654"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/45c08a752982116f3287afcd1bd9c50f4fab0c28"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/973acfdfe90c8a4e58ade97ff0653a498531ff2e"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52909.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-52909"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "nfsd: fix handling of cached open files in nfsd4_open codepath"
}