Chapters 5 and Chapter 6 of Pfleetzer's book relates to Operating System and Network Security, but are quite extensive with many examples, so try to grasp the main concepts and theory. 

For the lab, it is nice to use Chapter 3 of Basin's book for Network Security.  For chapter 3 of Basin's book you need to download and install three VMs. For testing, we use VMs to exploit security, in order to be isolated from the outside world.  VMs are safer when we try security stuff, test linux kernel additions etc.

Chapter 2 of the same book, explains how to install and configure them, do it carefully. You can download the 3 VMs (Alice, Bob, Mallet) from https://infsec.ethz.ch/appliedlabbook.html
*Notice: You need at least 8GB RAM on your PC to run them simultaneously.

Then, once you do the setup as in Chapter 2, you can do the exercises from Chapter 3 of Basin's book. 

The book is: Applied Information Security - A Hands-on Approach, by David Basin,see https://infsec.ethz.ch - https://ibook.pub/ql/applied-information-security-a-hands-on-approach

Don't erase the VMs (you need them partly for Chapter 4).

Please let me know if you are able to download, install and do chapters 2 & 3 on your own (the descriptions in the book are very good). 

Ps. If you  have time you can also go through this related material & exercises:
1) Read about shellshock (2014 attack on bash shell):
https://en.wikipedia.org/wiki/Shellshock_(software_bug)
Shellshock exploit can be tried on an Ubuntu 16.04 VM. See Seed Labs course
https://seedsecuritylabs.org/Labs_16.04/Software/Shellshock/
2) Seed Labs offers a very interesting course with many other exploits, especially on software/system/network security: https://seedsecuritylabs.org/Labs_16.04/

