Excellent article! It explains how programs are laid out in memory.
From the blog post:
Memory management is the heart of operating systems; it is crucial for both programming and system administration. In the next few posts Iâ€™ll cover memory with an eye towards practical aspects, but without shying away from internals. While the concepts are generic, examples are mostly from Linux and Windows on 32-bit x86. This first post describes how programs are laid out in memory. Each process in a multi-tasking OS runs in its own memory sandbox. This sandbox is the virtual address space, which in 32-bit mode is always a 4GB block of memory addresses.
=> Anatomy of a Program in Memory
Nice introduction to SELinux and other option to enhance Linux security. Mandatory access control and role-based access control are relatively new to the Linux kernel. With the introduction of the LSM framework, new security modules will certainly become available. In addition to enhancements to the framework, it’s possible to stack security modules, allowing multiple security modules to coexist and provide maximum coverage for Linux’s security needs. New access-control methods will also be introduced as research into operating system security continues. From the article:
Linux has been described as one of the most secure operating systems available, but the National Security Agency (NSA) has taken Linux to the next level with the introduction of Security-Enhanced Linux (SELinux). SELinux takes the existing GNU/Linux operating system and extends it with kernel and user-space modifications to make it bullet-proof. If you’re running a 2.6 kernel today, you might be surprised to know that you’re using SELinux right now! This article explores the ideas behind SELinux and how it’s implemented.
=> Anatomy of Security-Enhanced Linux (SELinux) Architecture and implementation
This is a full-size PDF version ( poster ) from Oreilly.
Anatomy of a Linux System poster try to put most important things together. The result is indeed encyclopedic. Supporting the illustration are 19 written topics, with brief historical and educational descriptions of technologies such as Peer-to-Peer Communication, XML and HTML, Samba, Unix Command-Line Utilities, and even Java. Each topic has a list of key Web sites and useful books, including titles that don’t belong to O’Reilly–part of Tim’s insistence that the poster serve as a complete Linux resource. The poster also lists Linux magazines, conferences, major distributors, and, of course, major contributors.
=> Download Link [oreillynet.com] (163K)