---
id: CVE-2025-22127
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  f2fs: fix potential deadloop in prepare_compress_overwrite()

  Jan Prusakowski reported a kernel hang issue as below:

  When running xfstests on linux-next kernel (6.14.0…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  f2fs: fix potential deadloop in prepare_compress_overwrite()

  Jan Prusakowski reported a kernel hang issue as below:

  When running xfstests on linux-next kernel (6.14.0…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-667
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.6, < 6.14.2'
patched:
  - linux_kernel 6.14.2
published: '2025-04-16'
updated: '2026-09-07'
sourceUpdated: '2026-09-07T16:17:27.510'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-22127'
references:
  - url: 'https://git.kernel.org/stable/c/3147ee567dd9004a49826ddeaf0a4b12865d4409'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7215cf8ef54bdc9082dffac4662416d54961e258'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7cd460bd9e7c6e6c30a33982603f65fb5deab1e4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00145
epssPercentile: 0.03119
ingestedAt: '2026-09-07T17:14:49.587Z'
---

## Overview

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

f2fs: fix potential deadloop in prepare_compress_overwrite()

Jan Prusakowski reported a kernel hang issue as below:

When running xfstests on linux-next kernel (6.14.0-rc3, 6.12) I
encountered a problem in generic/475 test where fsstress process
gets blocked in __f2fs_write_data_pages() and the test hangs.
The options I used are:

MKFS_OPTIONS  -- -O compression -O extra_attr -O project_quota -O quota /dev/vdc
MOUNT_OPTIONS -- -o acl,user_xattr -o discard,compress_extension=* /dev/vdc /vdc

INFO: task kworker/u8:0:11 blocked for more than 122 seconds.
      Not tainted 6.14.0-rc3-xfstests-lockdep #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0    state:D stack:0     pid:11    tgid:11    ppid:2      task_flags:0x4208160 flags:0x00004000
Workqueue: writeback wb_workfn (flush-253:0)
Call Trace:
 <TASK>
 __schedule+0x309/0x8e0
 schedule+0x3a/0x100
 schedule_preempt_disabled+0x15/0x30
 __mutex_lock+0x59a/0xdb0
 __f2fs_write_data_pages+0x3ac/0x400
 do_writepages+0xe8/0x290
 __writeback_single_inode+0x5c/0x360
 writeback_sb_inodes+0x22f/0x570
 wb_writeback+0xb0/0x410
 wb_do_writeback+0x47/0x2f0
 wb_workfn+0x5a/0x1c0
 process_one_work+0x223/0x5b0
 worker_thread+0x1d5/0x3c0
 kthread+0xfd/0x230
 ret_from_fork+0x31/0x50
 ret_from_fork_asm+0x1a/0x30
 </TASK>

The root cause is: once generic/475 starts toload error table to dm
device, f2fs_prepare_compress_overwrite() will loop reading compressed
cluster pages due to IO error, meanwhile it has held .writepages lock,
it can block all other writeback tasks.

Let's fix this issue w/ below changes:
- add f2fs_handle_page_eio() in prepare_compress_overwrite() to
detect IO error.
- detect cp_error earler in f2fs_read_multi_pages().

## Affected

- `linux_kernel >= 5.6, < 6.14.2`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.14.2`