dvg_domains variable is not initialized clean in foreach loop

The DvG-domains module implements hook_dvg_default_permissions_alter. Therefore it loops through all provided default permissions and applies them accordingly.

There is a flaw in the code where the variable $domain_part is set, and used to determine if the permission should be set, but not initialized blank at the start of the loop. So the value can stay the same in two loops, while it should not.