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

gpio: sysfs: fix chip removal with GPIOs exported over sysfs

Currently if we export a GPIO over sysfs and unbind the parent GPIO
controller, the exported attribute will remain under /sys/class/gpio
because once we remove the parent device, we can no longer associate the
descriptor with it in gpiod_unexport() and never drop the final
reference.

Rework the teardown code: provide an unlocked variant of
gpiod_unexport() and remove all exported GPIOs with the sysfs_lock taken
before unregistering the parent device itself. This is done to prevent
any new exports happening before we unregister the device completely.