---
id: CVE-2025-71309
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fs/ntfs3: fix deadlock in ni_read_folio_cmpr

  Syzbot reported a task hung in ni_readpage_cmpr (now ni_read_folio_cmpr).
  This is caused by a lock inversion deadlock invo…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  fs/ntfs3: fix deadlock in ni_read_folio_cmpr

  Syzbot reported a task hung in ni_readpage_cmpr (now ni_read_folio_cmpr).
  This is caused by a lock inversion deadlock invo…
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 >= 6.19, < 6.19.4'
patched:
  - linux_kernel 6.19.4
published: '2026-05-27'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T13:10:00.187'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-71309'
references:
  - url: 'https://git.kernel.org/stable/c/cfe246b318106e1691bd6c9466c739e8559d25c2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e37a75bb866c29da954b51d0dd7670406246d9ee'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00106
epssPercentile: 0.01061
ingestedAt: '2026-10-14T13:30:58.505Z'
---

## Overview

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

fs/ntfs3: fix deadlock in ni_read_folio_cmpr

Syzbot reported a task hung in ni_readpage_cmpr (now ni_read_folio_cmpr).
This is caused by a lock inversion deadlock involving the inode mutex
(ni_lock) and page locks.

Scenario:
1. Task A enters ntfs_read_folio() for page X. It acquires ni_lock.
2. Task A calls ni_read_folio_cmpr(), which attempts to lock all pages in
   the compressed frame (including page Y).
3. Concurrently, Task B (e.g., via readahead) has locked page Y and
   calls ntfs_read_folio().
4. Task B waits for ni_lock (held by A).
5. Task A waits for page Y lock (held by B).
   -> DEADLOCK.

The fix is to restructure locking: do not take ni_lock in ntfs_read_folio().
Instead, acquire ni_lock inside ni_read_folio_cmpr() ONLY AFTER all required
page locks for the frame have been successfully acquired. This restores the
correct lock ordering (Page Lock -> ni_lock) consistent with VFS.

[almaz.alexandrovich@paragon-software.com: ni_readpage_cmpr was renamed to ni_read_folio_cmpr]

## Affected

- `linux_kernel >= 6.19, < 6.19.4`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.19.4`