James Kim 764723bd67 char: tlclk: fix use-after-free in tlclk_cleanup()
[ Upstream commit bbf003b779 ]

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.

Fixes: 1a80ba8827 ("[PATCH] Telecom Clock Driver for MPCBL0010 ATCA computer blade")
Signed-off-by: James Kim <james010kim@gmail.com>
Link: https://patch.msgid.link/20260503101131.64219-1-james010kim@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-07-24 16:03:15 +02:00
2026-07-24 16:03:06 +02:00
2026-05-23 13:03:09 +02:00
…
…
…
…
…
2026-05-23 13:03:09 +02:00
2026-07-04 13:42:28 +02:00
…

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
S
Description
No description provided
Readme
5.7 GiB
Languages
C 96.9%
Assembly 0.9%
Rust 0.6%
Shell 0.6%
Python 0.5%
Other 0.3%