{
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    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
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  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64108.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix busy dentry used after unmounting\n\nSince commit 340cea84f691c (\"cifs: open files should not hold ref on\nsuperblock\"), cifs file only holds the dentry ref_cnt, the cifs file\nclose work(cfile-\u003edeferred) could be executed after unmounting, which\nwill trigger a warning in generic_shutdown_super:\n BUG: Dentry 00000000a14a6845{i=c,n=file}  still in use (1) [unmount of\n cifs cifs]\n\nThe detailed processs is:\n   process A           process B           kworker\n fd = open(PATH)\n  vfs_open\n   file-\u003e__f_path = *path // dentry-\u003ed_lockref.count = 1\n   cifs_open\n    cifs_new_fileinfo\n     cfile-\u003edentry = dget(dentry) // dentry-\u003ed_lockref.count = 2\n close(fd)\n  __fput\n  cifs_close\n   queue_delayed_work(deferredclose_wq, cfile-\u003edeferred)\n  dput(dentry) // dentry-\u003ed_lockref.count = 1\n\t\t\t                 smb2_deferred_work_close\n\t\t\t\t\t  _cifsFileInfo_put\n\t\t\t\t\t   list_del(\u0026cifs_file-\u003eflist)\n                    umount\n\t\t     cleanup_mnt\n\t\t      deactivate_super\n\t\t       cifs_kill_sb\n\t\t        cifs_close_all_deferred_files_sb\n\t\t\t cifs_close_all_deferred_files\n\t\t\t  // cannot find cfile, skip _cifsFileInfo_put\n\t\t\tkill_anon_super\n\t\t\t generic_shutdown_super\n\t\t\t  shrink_dcache_for_umount\n\t\t\t   umount_check\n\t\t\t    WARN ! // dentry-\u003ed_lockref.count = 1\n\t\t\t\t\t   cifsFileInfo_put_final\n\t\t\t\t\t    dput(cifs_file-\u003edentry)\n\t\t                            // dentry-\u003ed_lockref.count = 0\n\nFix it by flushing 'deferredclose_wq' before calling kill_anon_super.\n\nFetch a reproducer in https://bugzilla.kernel.org/show_bug.cgi?id=221548.",
  "id": "CVE-2026-64108",
  "modified": "2026-08-14T03:51:31.683043347Z",
  "published": "2026-07-19T15:40:10.784Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5e7d9d0805e58fa3760894e73115b7a74024fd07"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bdc349a87f1fb02c18c4071858a06542bfea783d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c68337442f03953237a94577beb468ab2662a851"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c7364cea52531534676b9f7dbc0a477c11f4c050"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e1ffa6cf662383f95816eed1b623429d82675e75"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f2deaa2f409a4598eaa10f2a93a676c0632af248"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64108.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64108"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "cifs: Fix busy dentry used after unmounting"
}