{"id":"CVE-2026-89485","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89485","summary":"lockd: pin next file across nlm_inspect_file lock-drop","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nlockd: pin next file across nlm_inspect_file lock-drop\n\nnlm_traverse_files() pins the current file with f_count++ across\na mutex_unlock for nlm_inspect_file(), but nothing pins the saved\nnext pointer.  A concurrent nlm_release_file() can kfree the next\nfile during the unlock window, and the iterator dereferences freed\nmemory on the next loop step.\n\nPin both current and next before the lock-drop.  Advance by\nswapping the pinned cursors at the end of each iteration so next\nis always held alive across the unlock.\n\nAlways call nlm_file_release() after dropping the iteration pin,\nregardless of whether the file matched the predicate.  Use\nnlm_file_inuse(), which does a live walk of the inode lock list,\nrather than the cached f_locks field, so skipped files that never\nran nlm_inspect_file() are evaluated correctly.\n\nBecause every file in a hash bucket is now pinned and released,\nfiles skipped by the is_failover_file predicate that have no\nlocks, blocks, shares, or external references are deleted during\ntraversal.  The old code never evaluated skipped files for\ncleanup.  The new behavior is intentional: such files are stale\nand should not persist in the table.","published":"2026-09-11T19:43:39.403Z","modified":"2026-09-14T03:46:07.413814626Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.12.109"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/41f0a6d31615fcae261bf28a0aa50050dc93a401"},{"type":"WEB","url":"https://git.kernel.org/stable/c/526c49cff3f72c3ec74752016380c7567040581b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c24bdb7df2f34bdc38ca8a73796f5acb40f1830c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e999a88133654c6dfc68487fb49da5f20dfa2d4f"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89485.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89485"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:46:07.413814626Z"}}