---
id: CVE-2023-53484
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  lib: cpu_rmap: Avoid use after free on rmap->obj array entries

  When calling irq_set_affinity_notifier() with NULL at the notify
  argument, it will cause freeing of the …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  lib: cpu_rmap: Avoid use after free on rmap->obj array entries

  When calling irq_set_affinity_notifier() with NULL at the notify
  argument, it will cause freeing of the …
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'
cwe:
  - CWE-416
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 3.8.1, < 4.14.316'
  - 'linux_kernel >= 4.15, < 4.19.284'
  - 'linux_kernel >= 4.20, < 5.4.244'
  - 'linux_kernel >= 5.5, < 5.10.181'
  - 'linux_kernel >= 5.11, < 5.15.113'
  - 'linux_kernel >= 5.16, < 6.1.30'
  - 'linux_kernel >= 6.2, < 6.3.4'
  - linux_kernel = 3.8
patched:
  - linux_kernel 6.3.4
published: '2025-10-01'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T22:17:40.497'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-53484'
references:
  - url: 'https://git.kernel.org/stable/c/4e0473f1060aa49621d40a113afde24818101d37'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/67bca5f1d644f4e79b694abd8052a177de81c37f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/981f339d2905b6a92ef59358158b326493aecac5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c6ed54dd90698dc0744d669524cc1c122ded8a16'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c9115f49cf260d24d8b5f2d9a4b63cb31a627bb4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cc2d2b3dbfb0ba57bc027fb7e1121250c50e4000'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d1308bd0b24cb1d78fa2747d5fa3e055cc628a48'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f748e15253833b771acbede14ea98f50831ac289'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00164
epssPercentile: 0.05515
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-15T21:34:49.139376Z'
ingestedAt: '2026-10-15T22:48:25.404Z'
---

## Overview

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

lib: cpu_rmap: Avoid use after free on rmap->obj array entries

When calling irq_set_affinity_notifier() with NULL at the notify
argument, it will cause freeing of the glue pointer in the
corresponding array entry but will leave the pointer in the array. A
subsequent call to free_irq_cpu_rmap() will try to free this entry again
leading to possible use after free.

Fix that by setting NULL to the array entry and checking that we have
non-zero at the array entry when iterating over the array in
free_irq_cpu_rmap().

The current code does not suffer from this since there are no cases
where irq_set_affinity_notifier(irq, NULL) (note the NULL passed for the
notify arg) is called, followed by a call to free_irq_cpu_rmap() so we
don't hit and issue. Subsequent patches in this series excersize this
flow, hence the required fix.

## Affected

- `linux_kernel >= 3.8.1, < 4.14.316`
- `linux_kernel >= 4.15, < 4.19.284`
- `linux_kernel >= 4.20, < 5.4.244`
- `linux_kernel >= 5.5, < 5.10.181`
- `linux_kernel >= 5.11, < 5.15.113`
- `linux_kernel >= 5.16, < 6.1.30`
- `linux_kernel >= 6.2, < 6.3.4`
- `linux_kernel = 3.8`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.3.4`