---
id: CVE-2026-53368
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage

  f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion
  with the checkpoint path, …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage

  f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion
  with the checkpoint path, …
severity: none
published: '2026-07-19'
updated: '2026-07-19'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53368'
references:
  - url: 'https://git.kernel.org/stable/c/019f9dda7f66e55eb94cd32e1d3fff5835f73fbc'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b28a83ea4934215b5de906c3ee4fbfbc651573e0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/bedb710b63ae1bd617e65d0a8cf6cea1200b3753'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00169
epssPercentile: 0.05455
ingestedAt: '2026-07-19T14:31:07.160Z'
---

## Overview

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

f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage

f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion
with the checkpoint path, which can result in an incorrect inode block
marking state. The scenario is as follows:

create & write & fsync 'file A'                 write checkpoint
- f2fs_do_sync_file // inline inode
 - f2fs_write_inode // inode folio is dirty
                                                - f2fs_write_checkpoint
                                                 - f2fs_flush_merged_writes
                                                 - f2fs_sync_node_pages
 - f2fs_fsync_node_pages // no dirty node
 - f2fs_need_inode_block_update // return true
 - f2fs_fsync_node_pages // inode dirtied
  - f2fs_need_dentry_mark //return true
                                                 - f2fs_flush_nat_entries
                                                - f2fs_write_checkpoint end
  - __write_node_folio // inode with DENT_BIT_SHIFT set
  SPO, "fsck --dry-run" find inode has already checkpointed but still
  with DENT_BIT_SHIFT set

The state observed by f2fs_need_dentry_mark() can differ from the state
observed in __write_node_folio() after acquiring sbi->node_write. The
root cause is that the semantics of IS_CHECKPOINTED and
HAS_FSYNCED_INODE are only guaranteed after the checkpoint write has
fully completed.

This patch moves set_dentry_mark() into __write_node_folio() and
protects it with the sbi->node_write lock.

## Remediation

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