Memory leak GetNamedSecurityInfoW

I'm trying to get file owner information (domain and user name) with ctypes. In python to get files list I used os.walk.

for root, dirs, files in os.walk("c:\\"):    for file in files:    filename = os.path.join(root, file)    owner = PL_Files.get_fileowner(filename)    print(owner)

to get owner information in 'PL_Files.get_fileowner', I'm using GetNamedSecurityInfoW. It's works well (it returns domain and user name).

@staticmethoddef get_fileowner(filename):    dwRet = 0    pSidOwner = c_void_p()    ppSecurityDescriptor = c_void_p()    dwAcctName = DWORD()    dwDomainName = DWORD()    peUse = DWORD(SidTypeUnknown)    dwRet = GetNamedSecurityInfoW(filename, SE_FILE_OBJECT, OWNER_SECURITY_INFORMATION, byref(pSidOwner), None, None, None, None)        if dwRet != ERROR_SUCCESS:            return "-1"        LookupAccountSidW(None, pSidOwner, None, byref(dwAcctName), None, byref(dwDomainName), byref(peUse))        AcctName = create_unicode_buffer(dwAcctName.value + 2)        DomainName = create_unicode_buffer(dwDomainName.value + 2)        if LookupAccountSidW(None, pSidOwner, AcctName, byref(dwAcctName), DomainName, byref(dwDomainName), byref(peUse)):            return "{}\{}".format(DomainName.value, AcctName.value)        else:            return "-1"

The issue is that every every calls to PL_Files.get_fileowner(filename) my process memory increasing with about 2MB.

Same result when I commented (didn't call) LookupAccountSidW function. So I think I have a problem with GetNamedSecurityInfoW function. GetNamedSecurityInfoW doesn't need freeing memory (if you don't use ppSecurityDescriptor).

Function prototype:

GetNamedSecurityInfoW = ADVAPI32.GetNamedSecurityInfoWGetNamedSecurityInfoW.restype = DWORDGetNamedSecurityInfoW.argtypes = [c_wchar_p, INT, DWORD, c_void_p, c_void_p, c_void_p, c_void_p, c_void_p]