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

ACPI: processor: Unregister cpufreq notifier on init failure

acpi_processor_driver_init() registers the cpufreq policy notifier before
registering the ACPI processor driver and setting up CPU hotplug state.

If driver_register() or cpuhp_setup_state() fails, the error path only
unregisters the ACPI processor driver and the idle driver. The cpufreq
notifier remains registered even though initialization failed.

Mirror the module exit path on the init failure path and unregister the
cpufreq notifier when it has been registered.