---
id: CVE-2026-68435
title: 'LoongArch: Fix address space mismatch in kexec command line lookup'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  LoongArch: Fix address space mismatch in kexec command line lookup

  When searching the loaded segments for the "kexec" command line marker,
  the kexec_load(2) path (file…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 <
    3b71f51fa3a247921408879eab2ddee82da8a980
  - >-
    Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 <
    eaa908d8d523b0ab75dab5ebd6662e70af5e5d7e
  - >-
    Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 <
    a94d6726ec8680a2b0c453fc782a543f68a1ea06
  - >-
    Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 <
    7a54e0cbaad4a5a09e7cc7a4f05d181048e98ca7
  - >-
    Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 <
    485ed44db5694d8d2e5027f63ad608e705286f30
  - Linux 6.1
published: '2026-08-12'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T12:44:08.300Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-68435'
references:
  - url: 'https://git.kernel.org/stable/c/3b71f51fa3a247921408879eab2ddee82da8a980'
  - url: 'https://git.kernel.org/stable/c/eaa908d8d523b0ab75dab5ebd6662e70af5e5d7e'
  - url: 'https://git.kernel.org/stable/c/a94d6726ec8680a2b0c453fc782a543f68a1ea06'
  - url: 'https://git.kernel.org/stable/c/7a54e0cbaad4a5a09e7cc7a4f05d181048e98ca7'
  - url: 'https://git.kernel.org/stable/c/485ed44db5694d8d2e5027f63ad608e705286f30'
tags:
  - cve.org
epss: 0.00206
epssPercentile: 0.10103
ingestedAt: '2026-10-21T12:48:53.598Z'
---

## Overview

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

LoongArch: Fix address space mismatch in kexec command line lookup

When searching the loaded segments for the "kexec" command line marker,
the kexec_load(2) path (file_mode == 0) passes the user-space segment
buffer straight to strncmp() through a bogus (char __user *) cast. This
dereferences a user pointer in kernel context, which is wrong and is
flagged by sparse:

  arch/loongarch/kernel/machine_kexec.c:84:51: sparse: incorrect type in
  argument 2 (different address spaces) @@ expected char const * @@ got
  char [noderef] __user *

Here copy the marker-sized prefix of each segment into a small on-stack
buffer with copy_from_user() before comparing, and skip segments that
fault. The subsequent copy_from_user() that stages the full command line
into the safe area is left unchanged.

## Affected

- `Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 < 3b71f51fa3a247921408879eab2ddee82da8a980`
- `Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 < eaa908d8d523b0ab75dab5ebd6662e70af5e5d7e`
- `Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 < a94d6726ec8680a2b0c453fc782a543f68a1ea06`
- `Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 < 7a54e0cbaad4a5a09e7cc7a4f05d181048e98ca7`
- `Linux >= 4a03b2ac06a5bcae29371866d9d11f5bfd4c9188 < 485ed44db5694d8d2e5027f63ad608e705286f30`
- `Linux 6.1`

## Remediation

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