Grsecurity - PaX

PaX

A major component bundled with grsecurity is PaX. Among other features, the patch flags data memory, the stack, for example, as non-executable and program memory as non-writable. The aim is to prevent memory from being overwritten, which can help to prevent many types of security vulnerabilities, such as buffer overflows. PaX also provides address space layout randomization (ASLR), which randomizes important memory addresses to reduce the probablility of attacks that rely on easily predicted memory addresses. PaX is not developed by the grsecurity developers. It is available in other Linux distributions such as Gentoo and directly from grsecurity.