{"id":"CVE-2026-89681","title":"nfsd: fix layout fence worker double-reference race","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix layout fence worker double-reference race\n\nThe workqueue core clears WORK_STRUCT_PENDING before the callback\nis invoked, so delayed_work_pending() in lm_break…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","cwe":["CWE-772"],"vendor":"Linux","product":"Linux","affected":["Linux >= f52792f484ba2316853736856dde19b7e7458861 < a278d361e0e8f242211891193d56483a7a9f47a8","Linux >= f52792f484ba2316853736856dde19b7e7458861 < 8580571227451384399b3fa53fcde19848c48e5a","Linux 7.1"],"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:50:54.644Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89681","references":[{"url":"https://git.kernel.org/stable/c/a278d361e0e8f242211891193d56483a7a9f47a8"},{"url":"https://git.kernel.org/stable/c/8580571227451384399b3fa53fcde19848c48e5a"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89681.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89681"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532389"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89681"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89681"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89681.mbox"}],"tags":["cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00553,"epssPercentile":0.46018,"scores":{"cna":9.8,"vendor":5.5},"ingestedAt":"2026-09-14T15:23:07.473Z","slug":"CVE-2026-89681","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix layout fence worker double-reference race\n\nThe workqueue core clears WORK_STRUCT_PENDING before the callback\nis invoked, so delayed_work_pending() in lm_breaker_timedout() can\nreturn false while the fence worker is already running. This lets\nthe breaker take a duplicate sc_count reference and schedule a new\nworker that coalesces with the in-progress one. The extra reference\nis never put, leaking the layout stateid.\n\nReplace the racy delayed_work_pending() check with an\nls_fence_inflight boolean set atomically with\nrefcount_inc_not_zero() under ls_lock, and cleared under ls_lock\nbefore the final nfs4_put_stid() on the dispose path; the retry\npath intentionally retains it.  Remove the self-rearm\nmod_delayed_work() at the top of the worker.\n\n## Affected\n\n- `Linux >= f52792f484ba2316853736856dde19b7e7458861 < a278d361e0e8f242211891193d56483a7a9f47a8`\n- `Linux >= f52792f484ba2316853736856dde19b7e7458861 < 8580571227451384399b3fa53fcde19848c48e5a`\n- `Linux 7.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-10-05 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89681.json)","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":224625,"id":"CVE-2026-89681","ts":1792401442328,"field":"cvss","old":"5.5","new":"9.8"},{"seq":224624,"id":"CVE-2026-89681","ts":1792401442328,"field":"severity","old":"medium","new":"critical"},{"seq":216233,"id":"CVE-2026-89681","ts":1791274045048,"field":"cvss","old":"7","new":"5.5"},{"seq":216232,"id":"CVE-2026-89681","ts":1791274045048,"field":"severity","old":"high","new":"medium"},{"seq":208477,"id":"CVE-2026-89681","ts":1790005712935,"field":"cvss","old":"5.3","new":"7"},{"seq":208476,"id":"CVE-2026-89681","ts":1790005712935,"field":"severity","old":"medium","new":"high"},{"seq":202826,"id":"CVE-2026-89681","ts":1789403732563,"field":"cvss","old":"9.8","new":"5.3"},{"seq":202825,"id":"CVE-2026-89681","ts":1789403732563,"field":"severity","old":"critical","new":"medium"},{"seq":197752,"id":"CVE-2026-89681","ts":1789384318701,"field":"cvss","old":"5.3","new":"9.8"},{"seq":197751,"id":"CVE-2026-89681","ts":1789384318701,"field":"severity","old":"medium","new":"critical"},{"seq":183361,"id":"CVE-2026-89681","ts":1789356675044,"field":"cvss","old":"9.8","new":"5.3"},{"seq":183360,"id":"CVE-2026-89681","ts":1789356675044,"field":"severity","old":"critical","new":"medium"},{"seq":153554,"id":"CVE-2026-89681","ts":1789285351261,"field":"cvss","old":null,"new":"9.8"},{"seq":153553,"id":"CVE-2026-89681","ts":1789285351261,"field":"severity","old":"none","new":"critical"},{"seq":147265,"id":"CVE-2026-89681","ts":1789270205531,"field":"cvss","old":null,"new":"5.3"},{"seq":147264,"id":"CVE-2026-89681","ts":1789270205531,"field":"severity","old":"none","new":"medium"},{"seq":109024,"id":"CVE-2026-89681","ts":1789183730005,"field":"cvss","old":null,"new":"5.3"},{"seq":109023,"id":"CVE-2026-89681","ts":1789183730005,"field":"severity","old":"none","new":"medium"}]}