Book Image

Practical Linux Security Cookbook - Second Edition

By : Tajinder Kalsi
Book Image

Practical Linux Security Cookbook - Second Edition

By: Tajinder Kalsi

Overview of this book

Over the last few years, system security has gained a lot of momentum and software professionals are focusing heavily on it. Linux is often treated as a highly secure operating system. However, the reality is that Linux has its share of security ?aws, and these security ?aws allow attackers to get into your system and modify or even destroy your important data. But there’s no need to panic, since there are various mechanisms by which these ?aws can be removed, and this book will help you learn about different types of Linux security to create a more secure Linux system. With a step-by-step recipe approach, the book starts by introducing you to various threats to Linux systems. Then, this book will walk you through customizing the Linux kernel and securing local files. Next, you will move on to managing user authentication both locally and remotely and mitigating network attacks. Later, you will learn about application security and kernel vulnerabilities. You will also learn about patching Bash vulnerability, packet filtering, handling incidents, and monitoring system logs. Finally, you will learn about auditing using system services and performing vulnerability scanning on Linux. By the end of this book, you will be able to secure your Linux systems and create a robust environment.
Table of Contents (20 chapters)
Title Page
Copyright and Credits
Contributors
Packt Upsell
Preface
Index

Chapter 2. Configuring a Secure and Optimized Kernel

The kernel is the core of any operating system, be it Windows or Linux. Linux is technically the kernel and not the complete operating system. Being the core of any operating system, the kernel is installed first and usually requires no manual configuration. Even if there are some kernel level updates to be installed, on a Linux system, it can be installed as a regular application. However, in some situations, compiling the kernel from source with some specific changes might be needed.

However, there might be a few situations where you need to compile the kernel yourself, from the source. These situations include:

  • Enabling experimental features in the kernel
  • Enabling new hardware support
  • Debugging the kernel
  • Exploring the kernel source code

Before you can start building the Linux kernel, you must ensure that a working boot media exists for the Linux system. This can be used to boot into the Linux system, if the boot loader is not configured...