Operating systems

Security

Operating systems security is hampered by their increasing complexity and the resulting inevitability of bugs. Because formal verification of operating systems may not be feasible, developers use operating system hardening to reduce vulnerabilities, e.g. address space layout randomization, control-flow integrity, access restrictions, and other techniques. There are no restrictions on who can contribute code to open source operating systems; such operating systems have transparent change histories and distributed governance structures. Open source developers strive to work collaboratively to find and eliminate security vulnerabilities, using code review and type checking to expunge malicious code. Andrew S. Tanenbaum advises releasing the source code of all operating systems, arguing that it prevents developers from placing trust in secrecy and thus relying on the unreliable practice of security by obscurity.