pefile.PE leaks memory

[baxitaurus]

PROBLEM

After the close method of a pefile.PE instance has been called, the garbage collector can't destroy the object due to a lot of reference cycles. This obviously causes memory leaks in long-time running processes.

HOW TO REPRODUCE

Python version 2.7.17
pefile version: 2018.8.8

Launch an htop parallely to the below code and look for RAM usage increasing more and more

import pefile

while True:
    pe = pefile.PE(<filepath>)
    pe.close()

or simply run the below code:

import pefile

class Test(pefile.PE):
    def __del__(self):
        print("Destroyed")

pe = Test(<filepath>)
pe.close()
pe = None

...won't print at all.

WORKAROUND (ugly)

Create a wrapper around the PE class:

class MyPE(pefile.PE):
    def close_recursive(obj, target):
        if isinstance(obj, list):
            for val in obj:
                close_recursive(val, target)
        elif isinstance(obj, object):
            try:
                dictobj = obj.__dict__
                if target in dictobj:
                    setattr(obj, target, None)
                for attr, val in dictobj.items():
                    close_recursive(val, target)
            except:
                pass

    def close(self):
        for attr, val in self.__dict__.items():
            close_recursive(val, "pe")
        super(MyPE, self).close()