---
id: CVE-2026-90037
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  NFSD: Prevent client use-after-free during close_lru reaping

  An nfs4_openowner left on nn->close_lru after its final CLOSE keeps
  its last closed stateid in oo_last_clo…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  NFSD: Prevent client use-after-free during close_lru reaping

  An nfs4_openowner left on nn->close_lru after its final CLOSE keeps
  its last closed stateid in oo_last_clo…
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'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 217526e7ecc9f6f243e976772e81eab7ab986a4c <
    83dd59ac1c3455c2c7d8ddb582d980a13199b9b3
  - >-
    Linux >= 217526e7ecc9f6f243e976772e81eab7ab986a4c <
    e57a9ed34ea8c17e831de59b8f1a6b2d80d347a1
  - >-
    Linux >= 217526e7ecc9f6f243e976772e81eab7ab986a4c <
    2330b788d732f43668b965b3105b37ceb276dfea
  - Linux 3.17
published: '2026-09-16'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T14:17:27.983'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90037'
references:
  - url: 'https://git.kernel.org/stable/c/0763482227822f7343557f086afc382086d56c4c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/2330b788d732f43668b965b3105b37ceb276dfea'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/83dd59ac1c3455c2c7d8ddb582d980a13199b9b3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e57a9ed34ea8c17e831de59b8f1a6b2d80d347a1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00652
epssPercentile: 0.49205
ingestedAt: '2026-09-16T10:53:53.934Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

NFSD: Prevent client use-after-free during close_lru reaping

An nfs4_openowner left on nn->close_lru after its final CLOSE keeps
its last closed stateid in oo_last_closed_stid, holding only a raw
pointer to its nfs4_client. The laundromat reaps timed-out entries,
drops nn->client_lock, and calls nfs4_put_stid(), which dereferences
the client through cl_lock. Nothing pins the client across that
window, so a concurrent force_expire_client() can free it and
nfs4_put_stid() reads freed memory. __destroy_client() hits the same
race, walking clp->cl_openowners without cl_lock.

Pin the client with cl_rpc_users before dropping client_lock, and
skip clients already expiring. __destroy_client() then cleans up its
own close_lru entries through release_last_closed_stateid(), so
teardown no longer races the laundromat.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.