grsecurity

Grsecurity is an extensive security enhancement to the Linux kernel that defends against a wide range of security threats through intelligent access control, memory corruption-based exploit prevention, and a host of other system hardening that generally require no configuration. It has been actively developed and maintained for the past 13 years. Commercial support for grsecurity is available through Open Source Security, Inc.

It offers among many other features:

• An intelligent and robust Role-Based Access Control (RBAC) system that can generate least privilege policies for your entire system with no configuration
• Change root (chroot) hardening
• /tmp race prevention
• Extensive auditing
• Prevention of arbitrary code execution, regardless of the technique used (stack smashing, heap corruption, etc)
• Prevention of arbitrary code execution in the kernel
• Randomization of the stack, library, and heap bases
• Kernel stack base randomization
• Protection against exploitable null-pointer dereference bugs in the kernel
• Reduction of the risk of sensitive information being leaked by arbitrary-read kernel bugs
• A restriction that allows a user to only view his/her processes
• Security alerts and audits that contain the IP address of the person causing the alert