---
id: CVE-2026-43109
title: 'x86: shadow stacks: proper error handling for mmap lock'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  x86: shadow stacks: proper error handling for mmap lock

  김영민 reports that shstk_pop_sigframe() doesn't check for errors from
  mmap_read_lock_killable(), which is a silly…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 <
    c79cf42321600e931933e11f94aba8b245d4cd66
  - >-
    Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 <
    1a30468eff661937d978495644d2e5ebfeef5ce6
  - >-
    Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 <
    c64cebcc5c4f223dbcbe7dcdf74908fc092a0aa4
  - >-
    Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 <
    262b6d38a81d51b135db81e1f30c13d30e38feee
  - >-
    Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 <
    52f657e34d7b21b47434d9d8b26fa7f6778b63a0
  - Linux 6.6
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T15:28:39.316247Z'
published: '2026-05-06'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T15:32:31.640Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-43109'
references:
  - url: 'https://git.kernel.org/stable/c/c79cf42321600e931933e11f94aba8b245d4cd66'
  - url: 'https://git.kernel.org/stable/c/1a30468eff661937d978495644d2e5ebfeef5ce6'
  - url: 'https://git.kernel.org/stable/c/c64cebcc5c4f223dbcbe7dcdf74908fc092a0aa4'
  - url: 'https://git.kernel.org/stable/c/262b6d38a81d51b135db81e1f30c13d30e38feee'
  - url: 'https://git.kernel.org/stable/c/52f657e34d7b21b47434d9d8b26fa7f6778b63a0'
tags:
  - cve.org
epss: 0.00114
epssPercentile: 0.01464
ingestedAt: '2026-11-06T15:54:04.022Z'
---

## Overview

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

x86: shadow stacks: proper error handling for mmap lock

김영민 reports that shstk_pop_sigframe() doesn't check for errors from
mmap_read_lock_killable(), which is a silly oversight, and also shows
that we haven't marked those functions with "__must_check", which would
have immediately caught it.

So let's fix both issues.

## Affected

- `Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 < c79cf42321600e931933e11f94aba8b245d4cd66`
- `Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 < 1a30468eff661937d978495644d2e5ebfeef5ce6`
- `Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 < c64cebcc5c4f223dbcbe7dcdf74908fc092a0aa4`
- `Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 < 262b6d38a81d51b135db81e1f30c13d30e38feee`
- `Linux >= 7fad2a432cd35bbf104d2d9d426e74902f22aa95 < 52f657e34d7b21b47434d9d8b26fa7f6778b63a0`
- `Linux 6.6`

## Remediation

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