CVE-2026-80622

Summary

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.

Affected Software

Weaknesses

References

• https://git.kernel.org/stable/c/09d8d2a46a9ec9ff728f3159a174a2ab25dd0f0a
• https://git.kernel.org/stable/c/96902299a22d126ef5eb3f45cd5d8ceea9e6a735
• https://git.kernel.org/stable/c/166dd1d5265e067459e674c11688919901813ec2
• https://git.kernel.org/stable/c/764723bd67a6c8f53a8d8309211fb039e2ebcf49
• https://git.kernel.org/stable/c/c3f0cd76561ae611c2d247ee96dfd559e4197cb7
• https://git.kernel.org/stable/c/3d5e4cc0d9dce79b0429da3134ac7b072ab9009f
• https://git.kernel.org/stable/c/42223445607a9a5df3cb1c4729abfe3a5085e7ce
• https://git.kernel.org/stable/c/bbf003b7794d6ad6f939fdd29f1f1bde8ac554c1

• ←Previous
• Next→