---
id: CVE-2026-89705
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nfsd: restore rq_status_counter to even on all nfsd_dispatch() exit paths

  nfsd_dispatch() sets rq_status_counter to an odd value once a request has
  been decoded, and b…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nfsd: restore rq_status_counter to even on all nfsd_dispatch() exit paths

  nfsd_dispatch() sets rq_status_counter to an odd value once a request has
  been decoded, and b…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H'
cwe:
  - CWE-125
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= bd9d6a3efa9709e653aafbeb859289feccb8e70c <
    df5500ab85df661d9e4439e4c456787181fbd5ff
  - >-
    Linux >= bd9d6a3efa9709e653aafbeb859289feccb8e70c <
    b08c30f08d57f30699d36809d92f0b683dca261f
  - >-
    Linux >= bd9d6a3efa9709e653aafbeb859289feccb8e70c <
    f6045886fe3f14f269f683d64021b004a50d0efa
  - Linux 6.7
published: '2026-09-11'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T11:17:55.020'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89705'
references:
  - url: 'https://git.kernel.org/stable/c/b08c30f08d57f30699d36809d92f0b683dca261f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/df5500ab85df661d9e4439e4c456787181fbd5ff'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f6045886fe3f14f269f683d64021b004a50d0efa'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89705.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89705'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532490'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89705'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89705'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89705.mbox
  - url: 'https://git.kernel.org/stable/c/5773e00cc0f9e34983bd29ba2a607c6b14258e00'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.0016
epssPercentile: 0.05058
scores:
  nvd: 7.1
  cna: 7.1
  vendor: 7
ingestedAt: '2026-09-14T15:23:07.472Z'
---

## Overview

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

nfsd: restore rq_status_counter to even on all nfsd_dispatch() exit paths

nfsd_dispatch() sets rq_status_counter to an odd value once a request has
been decoded, and back to an even value once it has been fully processed,
forming a seq-lock like protocol with the lockless reader in
nfsd_nl_rpc_status_get_dumpit().

Only the fully successful path restored the counter to even. The cache-hit
(RC_REPLY), drop (RC_DROPIT / RQ_DROPME) and encode-error paths all return
after the odd-valued store without ever bringing the counter back to even.
Once one of those paths is taken, rq_status_counter is left odd: the next
request's decode ORs in 1 (still odd) and only a subsequent successful
encode restores even. While stuck odd, the dumpit reader treats the rqstp
fields as stable and its retry check compares against the same unchanging
odd value, so it never detects concurrent mutation. This exposes actively
mutating fields (e.g. args->ops / args->opcnt during compound decode and
release) to the lockless reader, which can read past the end of the
8-element inline ops array.

Add a helper that advances the counter to the next even value and call it
on every return path that follows the odd-valued store. The decode-error
path is left untouched as it is reached before the counter is set odd.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89705.json)