In the Linux kernel, the following vulnerability has been resolved:
hwmon: Fix potential UAF in pec_store
Sashiko reports:
In pec_store(), a guard(mutex)(&hwdev->lock) is taken. If the chip write
operation returns an error other than -EOPNOTSUPP, the code jumps to the
put label, which calls put_device(hdev). If this drops the final reference,
the device is freed. When the function then returns, the guard cleanup
function runs and attempts to unlock the freed mutex.
Use scoped_guard() instead of guard() to avoid the problem.
