6.033 | Spring 2018 | Undergraduate

Computer System Engineering

Week 13: Security Part III

Memory Corruption Assignment

For this recitation, you’ll be reading “SoK: Eternal War in Memory (PDF)” by Lazlo Szekeres, Mathia Payer, Tao Wei, and Dawn Song. This paper describes a variety of memory corruption bugs, and potential solutions. Don’t worry about memorizing every single type of attack described in this paper; aim to understand what makes these attacks possible, and the general ideas behind the solutions.

(We’ve also written a quick guide (PDF) to some of the memory corruption bugs described in the paper, which you might want to take a look at before you start reading.)

The paper is fairly well organized:

  • Section I gives you an introduction to the general problem, and a brief history of memory corruption attacks and defenses.
  • Section II details many different types of memory corruption attacks. Figure 1 is particularly helpful in organizing these attacks and their defenses. As stated above, don’t worry about memorizing every single type of attack described in this section; aim to understand what makes the various attacks different from one another, as well as what makes each of these possible in the first place.
  • Section III describes two currently-deployed defenses, and their drawbacks.
  • Section IV outlines some properties and requirements for defenses against memory corruption bugs; those defenses are discussed in Sections V-VIII (each section is a different category of defense).
  • Sections IX and X conclude.

As you read, think about the following:

  • Stack canaries (or cookies) and ASLR are both widely-deployed. What is good about those solutions? What attacks do they prevent? What attacks don’t they prevent?
  • Many of the proposed solutions worsen performance. Are we at a point where these performance hits are outweighed by security concerns?

Questions for Recitation

Before you come to this recitation, write up (on paper) a brief answer to the following (really—we don’t need more than a couple sentences for each question).  

Your answers to these questions should be in your own words, not direct quotations from the paper.

  • What do the authors mean by “the eternal war in memory”?
  • How has this war progressed over time? (i.e., how have attacks and solutions evolved)
  • Why hasn’t the war ended?

As always, there are multiple correct answers for each of these questions.

Course Info

As Taught In
Spring 2018
Learning Resource Types
Lecture Notes
Written Assignments
Projects with Examples
Instructor Insights