---
id: CVE-2026-63812
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node()

  When __destroy_extent_node() sets the inode flag FI_NO_EXTENT, it does
  not reset the length of the…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node()

  When __destroy_extent_node() sets the inode flag FI_NO_EXTENT, it does
  not reset the length of the…
severity: none
published: '2026-07-19'
updated: '2026-07-19'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-63812'
references:
  - url: 'https://git.kernel.org/stable/c/1f70ddb28a3c71df124da5fa4040c808116d6bb9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/20190e498057997532c7f186d081011f18e0a462'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/58a5deb220bcac4c73bf58954c0845644c997487'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7e4d8f98be63f98856a5176b9188dada6e7ba9ee'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/edf12cbeeeabe799bd2ee21fdb5c336cce6fbad7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
ingestedAt: '2026-07-20T09:37:17.929Z'
epss: 0.00126
epssPercentile: 0.01962
---

## Overview

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

f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node()

When __destroy_extent_node() sets the inode flag FI_NO_EXTENT, it does
not reset the length of the largest extent to 0 and update the inode
folio. Since modifications to the extent tree are disallowed afterward,
the cached largest extent may become stale. This can trigger the
following error in xfstests generic/388:

F2FS-fs (dm-0): sanity_check_extent_cache: inode (ino=1761) extent info [220057, 57, 6] is incorrect, run fsck to fix

In the f2fs_drop_inode path, __destroy_extent_node() does not need to
guarantee that et->node_cnt is 0, because concurrency with writeback
is expected in this path, and writeback may update the extent cache.

This patch reverts commit ed78aeebef05 ("f2fs: fix node_cnt race between
extent node destroy and writeback"), and remove the unnecessary zero
check of et->node_cnt.

## Remediation

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