---
id: CVE-2026-80689
title: 'tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions

  mmio_trace_rw() and mmio_trace_mapping() retrieve mmio_trace_array into
  tr and pass it to _…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    dc1b1a057b3bb901f83433700e604fe0ae67c5f2
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    6aee2d478545c089dd5d055d3c9f0c7ea034fb80
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    4e4ab09db7899d7f2d2293a18adf0fa200a27e73
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    2df964d141270c40f07547b0c2e0a51e2573d46d
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    876014b4eeb927146430e7591cf959a7ceb8d64a
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    a20a0010eb6485f60cd64e15ebc85a4bd388642e
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    60234845142fddb27db89ebc00a65178421fb3a4
  - >-
    Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 <
    12b80cdbc54cf615b4717a4e8180063408091ea2
  - Linux 2.6.27
published: '2026-08-28'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T11:58:50.409Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-80689'
references:
  - url: 'https://git.kernel.org/stable/c/dc1b1a057b3bb901f83433700e604fe0ae67c5f2'
  - url: 'https://git.kernel.org/stable/c/6aee2d478545c089dd5d055d3c9f0c7ea034fb80'
  - url: 'https://git.kernel.org/stable/c/4e4ab09db7899d7f2d2293a18adf0fa200a27e73'
  - url: 'https://git.kernel.org/stable/c/2df964d141270c40f07547b0c2e0a51e2573d46d'
  - url: 'https://git.kernel.org/stable/c/876014b4eeb927146430e7591cf959a7ceb8d64a'
  - url: 'https://git.kernel.org/stable/c/a20a0010eb6485f60cd64e15ebc85a4bd388642e'
  - url: 'https://git.kernel.org/stable/c/60234845142fddb27db89ebc00a65178421fb3a4'
  - url: 'https://git.kernel.org/stable/c/12b80cdbc54cf615b4717a4e8180063408091ea2'
tags:
  - cve.org
epss: 0.00176
epssPercentile: 0.07429
ingestedAt: '2026-09-14T15:23:07.456Z'
---

## Overview

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

tracing/mmiotrace: Add NULL check for mmio_trace_array in logging functions

mmio_trace_rw() and mmio_trace_mapping() retrieve mmio_trace_array into
tr and pass it to __trace_mmiotrace_rw() and __trace_mmiotrace_map().
If these functions are invoked while mmio_trace_array is NULL (e.g. before
initialization or after disabled), accessing tr->array_buffer.buffer will
result in a NULL pointer dereference crash.

Fix this by adding an explicit NULL check for tr at the beginning of
__trace_mmiotrace_rw() and __trace_mmiotrace_map().

## Affected

- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < dc1b1a057b3bb901f83433700e604fe0ae67c5f2`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < 6aee2d478545c089dd5d055d3c9f0c7ea034fb80`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < 4e4ab09db7899d7f2d2293a18adf0fa200a27e73`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < 2df964d141270c40f07547b0c2e0a51e2573d46d`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < 876014b4eeb927146430e7591cf959a7ceb8d64a`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < a20a0010eb6485f60cd64e15ebc85a4bd388642e`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < 60234845142fddb27db89ebc00a65178421fb3a4`
- `Linux >= f984b51e0779a6dd30feedc41404013ca54e5d05 < 12b80cdbc54cf615b4717a4e8180063408091ea2`
- `Linux 2.6.27`

## Remediation

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