---
id: CVE-2026-80638
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ocfs2: fix out-of-bounds write in ocfs2_remove_refcount_extent

  [BUG]
  Unlinking a refcounted file whose refcount tree has leaf blocks
  triggers a fortify panic due to an…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ocfs2: fix out-of-bounds write in ocfs2_remove_refcount_extent

  [BUG]
  Unlinking a refcounted file whose refcount tree has leaf blocks
  triggers a fortify panic due to an…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
published: '2026-08-28'
updated: '2026-08-29'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80638'
references:
  - url: 'https://git.kernel.org/stable/c/1ec3cca2d8b6b9ff6584ca626d4c8918bbf48d44'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f5255516ec7add3a6d5d37853ad5a9a9ddb14305'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00508
epssPercentile: 0.4088
ingestedAt: '2026-08-30T03:46:31.177Z'
---

## Overview

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

ocfs2: fix out-of-bounds write in ocfs2_remove_refcount_extent

[BUG]
Unlinking a refcounted file whose refcount tree has leaf blocks
triggers a fortify panic due to an out-of-bounds write.

[CAUSE]
When the last leaf block is removed from a refcount tree,
ocfs2_remove_refcount_extent() converts the root back to leaf mode
with a bulk memset on &rb->rf_records. rf_records sits in an anonymous
union with rf_list. rf_list.l_tree_depth aliases rf_records.rl_count,
and is 0 for a single-level tree. With rl_count equal to 0, the memset
writes past the 16-byte declared size of rf_records, which the fortify
checker catches.

[FIX]
Replace the bulk memset on &rb->rf_records with a correctly-bounded
memset on rl_recs[] alone, after setting rl_count to the correct value.

## Remediation

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