In the Linux kernel, the following vulnerability has been resolved:
power: supply: rt9455: quiesce delayed work before teardown
The threaded IRQ handler can queue pwr_rdy_work,
max_charging_time_work and batt_presence_work. pwr_rdy_work and
batt_presence_work can also queue max_charging_time_work, while
batt_presence_work can requeue itself.
rt9455_remove() cancels max_charging_time_work before
batt_presence_work. The latter can therefore queue
max_charging_time_work after it has already been cancelled:
rt9455_remove() workqueue
cancel pwr_rdy_work
cancel max_charging_time_work
batt_presence_work queues
max_charging_time_work
cancel batt_presence_work
return
devres frees rt9455_info
max_charging_time_work dereferences
rt9455_info
The IRQ also remains registered until devres cleanup and can queue more
work after any of the cancellation calls. If rt9455_hw_init() fails
after the IRQ has been requested, probe returns without cancelling work
that may already have been queued. A pending callback can then access
rt9455_info after it has been freed.
Register rt9455_cancel_all_delayed_works() through
devm_add_action_or_reset() right after devm_power_supply_register().
devres invokes the action in reverse registration order, after the
managed IRQ has been freed and before rt9455_info is released, so the
delayed works are drained in both rt9455_remove() and the probe error
path. Cancel pwr_rdy_work and batt_presence_work before
max_charging_time_work because both can queue the latter.
This issue was found by an in-house static analysis tool.
