What is "security context" and why is it set to "unknown"? I can't find anything about it. I found something about chcon and that doesn't actually define security context and what it's used for.
1 Answer
Note: Due to a huge oversight on my part, I forgot that Ubuntu uses AppArmor instead of SELinux. That said, AppArmor is "SELinux-like", and the same principles exist for both. For more information about AppArmor, see here.
The Security Context field refers to the SELinux context set on that particular file.
They are used primarily for SELinux enforcement -- namely, to decide whether a particular user has access to that particular file/resource. Think of them as the SELinux equivalent of an Access Control List.
SELinux itself is an advanced concept, and will usually not need to be used by the average end user. In the vast majority of cases, most things can be run through standard UNIX permissions, or alternatively filesystem ACLs (see man acl).
