Fear not, Linux admins: There are TOOLS to help you
Let's use my favourite distribution, CentOS, as an example. (CentOS is a near-identical repackaging of Red Hat Enterprise Linux.) By default, SELinux is turned on. In most situations, this is a great thing; SELinux provides a layer of sandboxing so that applications of a certain class can't impinge upon files belonging to applications or users of another class.
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