Bug 2525416 (CVE-2026-80622) - CVE-2026-80622 kernel: char: tlclk: fix use-after-free in tlclk_cleanup()
Summary: CVE-2026-80622 kernel: char: tlclk: fix use-after-free in tlclk_cleanup()
Keywords:
Status: NEW
Alias: CVE-2026-80622
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-28 07:43 UTC by OSIDB Bzimport
Modified: 2026-09-03 15:44 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)

Description OSIDB Bzimport 2026-08-28 07:43:53 UTC
In the Linux kernel, the following vulnerability has been resolved:

char: tlclk: fix use-after-free in tlclk_cleanup()

This patch improves the module cleanup process in the tlclk driver to
prevent potential use-after-free and race conditions.

Currently, the file_operations structure does not specify the .owner
field, which could allow the module to be unloaded while user-space
processes are still interacting with the device. Additionally, the
tlclk_cleanup() function frees the alarm_events memory before ensuring
that blocked processes in the waitqueue are fully awakened and that the
switchover_timer has completed.

To address these cases, this patch:
- Sets '.owner = THIS_MODULE' in tlclk_fops to safely defer module
  unloading while the device is in use.
- Updates tlclk_cleanup() to explicitly wake up all blocked readers
  (wake_up_all), properly release hardware I/O regions, and safely
  delete the timer (timer_delete_sync) prior to freeing memory.


Note You need to log in before you can comment on or make changes to this bug.