Value-Range Analysis of C Programs: Towards Proving the Absence of Buffer Overflow Vulnerabilities / Edition 1

by Axel Simon

Overview

A buffer overflow occurs when input is written into a memory buffer that is not large enough to hold the input. Buffer overflows may allow a malicious person to gain control over a computer system in that a crafted input can trick the defective program in to executing code that is encoded in the input itself. They are recognised as one of the most widespread forms of security vulnerability, and many workarounds, including new processor features, have been proposed to contain the threat. This book describes a static analysis that aims to prove the absence of buffer overflows in C programs. The analysis is conservative in the sense that it locates every possible overflow. Furthermore, it is fully automatic in that it requires no user annotations in the input program. The key idea of the analysis is to infera symbolic state for each p- gram point that describes the possible variable valuations that can arise at that point. The program is correct if the inferred values for array indices and pointer offsets lie within the bounds of the accessed buffer. The symbolic state consists of afinite set of linear inequalities whose feasible points induce a convex polyhedron that represents an approximation to possible variable valuations. The book formally describes how program operations are mapped to operations on polyhedra and details how to limit the analysis to those p- tions of structures and arrays that are relevant for verification. With respect to operations on string buffers, we demonstrate how to analyse C strings whose length is determined by anul character within the string.

Product Details

ISBN-13:	9781848000162
Publisher:	Springer London
Publication date:	06/19/2008
Edition description:	2008
Pages:	302
Product dimensions:	6.10(w) x 9.25(h) x 0.03(d)

Table of Contents

From the Contents: Preface.- Introduction.-Value Range Analysis.- Analysing C.- A Semantics for C.- Core C.- Related Work.- Part 1 Abstracting Soundly.- Abstract State Space.- Points-To Analysis.- Numeric Domains.- Taming Casting and Wrapping.- A Language Featuring Finite Integer Arithmetic.- Implicit Wrapping of Polyhedral Variables.- Explicit Wrapping of Polyhedral Variables.- An Abstract Semantics for SubC.- Discussion.- Overlapping Memory Accesses and Pointers.- Memory as a Set of Fields.- Mixing Values and Pointers.- Abstraction Relation.- Abstract Semantics.- Part II Ensuring Efficiency.- Planar Polyhedra.- Operations on Inequalities.- Operations on Sets of Inequalities.- The TVPI Abstract Domain.- The Integral TVPI Domain.- Interfacing Analysis and Numeric Domain.- Inferring Relevant Fields and Addresses.- Applying Widening in Fixpoint Calculations.- Part III Improving Precision.- Tracking String Lengths.- Widening with Landmarks .- Combining Points-To and Numeric Analysis.- Conclusion and Outlook

Editorial Reviews

From the reviews:

"This book describes a static analysis that aims to prove the absence of buffer overflows in C programs. … The book formally describes how program operations are mapped to operations on polyhedra. … Many concepts presented here carry over to other languages such as Java or assembler. So it will be useful to any researcher and student with an interest in static analysis of real-world programming languages." (Stefan Meyer, Zentralblatt MATH, Vol. 1155, 2009)

From the Publisher