Vulnerability Database

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Total vulnerabilities in the database

CVE-2025-71309 — linux / linux_kernel

Improper Locking

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.

[[email protected]: ni_readpage_cmpr was renamed to ni_read_folio_cmpr]

  • Published: May 27, 2026
  • Updated: Jun 27, 2026
  • CVE: CVE-2025-71309
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.5
  • AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CWEs:

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