---
id: CVE-2022-50746
title: 'erofs: validate the extent length for uncompressed pclusters'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  erofs: validate the extent length for uncompressed pclusters

  syzkaller reported a KASAN use-after-free:
  https://syzkaller.appspot.com/bug?extid=2ae90e873e97f1faf6f2

  T…
severity: high
cvss: 8.4
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 02827e1796b33f1794966f5c3101f8da2dfa9c1d <
    dc8b6bd587b13b85aff6e9d36cdfcd3f955cac9e
  - >-
    Linux >= 02827e1796b33f1794966f5c3101f8da2dfa9c1d <
    40c73b2ea9611b5388807be406f30f5e4e1162da
  - >-
    Linux >= 02827e1796b33f1794966f5c3101f8da2dfa9c1d <
    c505feba4c0d76084e56ec498ce819f02a7043ae
  - Linux 4.19
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-15T21:32:20.485898Z'
published: '2025-12-24'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T21:41:23.468Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2022-50746'
references:
  - url: 'https://git.kernel.org/stable/c/dc8b6bd587b13b85aff6e9d36cdfcd3f955cac9e'
  - url: 'https://git.kernel.org/stable/c/40c73b2ea9611b5388807be406f30f5e4e1162da'
  - url: 'https://git.kernel.org/stable/c/c505feba4c0d76084e56ec498ce819f02a7043ae'
tags:
  - cve.org
epss: 0.00213
epssPercentile: 0.10853
ingestedAt: '2026-10-15T22:48:25.382Z'
---

## Overview

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

erofs: validate the extent length for uncompressed pclusters

syzkaller reported a KASAN use-after-free:
https://syzkaller.appspot.com/bug?extid=2ae90e873e97f1faf6f2

The referenced fuzzed image actually has two issues:
 - m_pa == 0 as a non-inlined pcluster;
 - The logical length is longer than its physical length.

The first issue has already been addressed.  This patch addresses
the second issue by checking the extent length validity.

## Affected

- `Linux >= 02827e1796b33f1794966f5c3101f8da2dfa9c1d < dc8b6bd587b13b85aff6e9d36cdfcd3f955cac9e`
- `Linux >= 02827e1796b33f1794966f5c3101f8da2dfa9c1d < 40c73b2ea9611b5388807be406f30f5e4e1162da`
- `Linux >= 02827e1796b33f1794966f5c3101f8da2dfa9c1d < c505feba4c0d76084e56ec498ce819f02a7043ae`
- `Linux 4.19`

## Remediation

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