---
id: CVE-2025-68240
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nilfs2: avoid having an active sc_timer before freeing sci

  Because kthread_stop did not stop sc_task properly and returned -EINTR,
  the sc_timer was not properly closed…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nilfs2: avoid having an active sc_timer before freeing sci

  Because kthread_stop did not stop sc_task properly and returned -EINTR,
  the sc_timer was not properly closed…
severity: none
published: '2025-12-16'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T13:10:00.187'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-68240'
references:
  - url: 'https://git.kernel.org/stable/c/2f65799e2a736d556d306440c4e1e8906736117a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/36049e81dc7f077e0e24d5b9688a7458beacef8f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9a6b60cb147d53968753a34805211d2e5e08c027'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00184
epssPercentile: 0.07378
ingestedAt: '2026-10-14T13:30:58.464Z'
---

## Overview

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

nilfs2: avoid having an active sc_timer before freeing sci

Because kthread_stop did not stop sc_task properly and returned -EINTR,
the sc_timer was not properly closed, ultimately causing the problem [1]
reported by syzbot when freeing sci due to the sc_timer not being closed.

Because the thread sc_task main function nilfs_segctor_thread() returns 0
when it succeeds, when the return value of kthread_stop() is not 0 in
nilfs_segctor_destroy(), we believe that it has not properly closed
sc_timer.

We use timer_shutdown_sync() to sync wait for sc_timer to shutdown, and
set the value of sc_task to NULL under the protection of lock
sc_state_lock, so as to avoid the issue caused by sc_timer not being
properly shutdowned.

[1]
ODEBUG: free active (active state 0) object: 00000000dacb411a object type: timer_list hint: nilfs_construction_timeout
Call trace:
 nilfs_segctor_destroy fs/nilfs2/segment.c:2811 [inline]
 nilfs_detach_log_writer+0x668/0x8cc fs/nilfs2/segment.c:2877
 nilfs_put_super+0x4c/0x12c fs/nilfs2/super.c:509

## Remediation

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