
Fedora Linux System Administration
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Linux file permissions control which users or groups of users access specific files. But a user with read or write access to a specific file could use that file in any way desired, even if that use is not what the file should be used for.
Linux standard file permissions succeed when files get used by a single owner and a single designated group of people.
File permissions fail to prevent some forms of unwanted access. They were not designed to control how a file gets used, but only who to allow to read, write, or run a file.
Linux standard file permissions are ownership-based, also known as discretionary access control (DAC).
The MAC rules are policy based, not by ownership.
There are two types of MAC: