---
id: CVE-2026-80991
title: 'net: ravb: serialize PTP clock teardown'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: ravb: serialize PTP clock teardown

  ravb_ptp_interrupt() can race with ravb_ptp_stop() and pass the clock to
  ptp_clock_event() while ptp_clock_unregister() is free…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-364
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c <
    b917f37bfcce919a969d66a044580a95b11df31c
  - >-
    Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c <
    695acb5534a9e366efb47b40c7487fc56488b09b
  - >-
    Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c <
    67a82e6f886beed0de8f8da08bb767e68fba952d
  - >-
    Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c <
    66b50c31419e7946e9aa325a468ad9b64c961a25
  - >-
    Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c <
    1cb9663789c5b7a12fcd419fcca6d6254c398252
  - Linux 4.2
published: '2026-09-11'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T12:47:22.150Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-80991'
references:
  - url: 'https://git.kernel.org/stable/c/b917f37bfcce919a969d66a044580a95b11df31c'
  - url: 'https://git.kernel.org/stable/c/695acb5534a9e366efb47b40c7487fc56488b09b'
  - url: 'https://git.kernel.org/stable/c/67a82e6f886beed0de8f8da08bb767e68fba952d'
  - url: 'https://git.kernel.org/stable/c/66b50c31419e7946e9aa325a468ad9b64c961a25'
  - url: 'https://git.kernel.org/stable/c/1cb9663789c5b7a12fcd419fcca6d6254c398252'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80991.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-80991'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532440'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-80991'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80991'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-80991.mbox
tags:
  - cve.org
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.00164
epssPercentile: 0.05539
scores:
  cna: 7.8
  vendor: 5.5
ingestedAt: '2026-09-14T15:23:07.476Z'
---

## Overview

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

net: ravb: serialize PTP clock teardown

ravb_ptp_interrupt() can race with ravb_ptp_stop() and pass the clock to
ptp_clock_event() while ptp_clock_unregister() is freeing it. This can
lead to a use-after-free.

Use READ_ONCE() and WRITE_ONCE() for lockless access to the clock pointer.
Atomically detach it with xchg() before disabling PTP interrupts, then
synchronize all IRQs which can invoke ravb_ptp_interrupt() before
unregistering the detached clock.

A handler which read the old pointer completes before the clock is
unregistered, while later handlers read NULL and skip the event.

## Affected

- `Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c < b917f37bfcce919a969d66a044580a95b11df31c`
- `Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c < 695acb5534a9e366efb47b40c7487fc56488b09b`
- `Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c < 67a82e6f886beed0de8f8da08bb767e68fba952d`
- `Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c < 66b50c31419e7946e9aa325a468ad9b64c961a25`
- `Linux >= a0d2f20650e81407d8e51ad2cbdc492861c74e9c < 1cb9663789c5b7a12fcd419fcca6d6254c398252`
- `Linux 4.2`

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80991.json)