Gain insights into using GDB for debugging in Linux. Explore disassembly, memory investigation, and register updates. Learn about pointers, stack, and function parameters in x64 architecture.

gdb.tar.gz

C2-LA

C4-L2

C4-L3

C4-L4

C4-L5

C6-L3

C8-L1

C9-L3

C10-L2

C10-L3

C11-L2

C13-L1

test

GNU Debugger (GDB) is used for debugging C/C++ programs in LINUX/UNIX environments. It is a good tool to investigate what is happening inside a program, and how the contents inside the memory are changed with the execution of the program.

The main focus of the course is the disassembly of the program, where we'll use simple operations in C. With the help of GDB, we'll examine the contents of the registers and memory. We'll also learn how they are changed while executing basic operations. We’ll then explore the use of pointers, stack, and function parameters, and analyze how different registers update their values. With the help of disassembly output, we’ll learn how a simple C program can be reconstructed. The disassembly output is important for debugging and core dump analysis. We’ll use assembly language for x64 architecture.

By the end of this course, you should be able to debug the programs and memory contents at assembly level when a program executes or probe into the problem when a program crashes.

Debugging, Disassembly & Reversing in Linux for x64 Architecture

Which register is used to pass function parameters?

Which register is used to pass function parameters?

What value is stored in the local variable if it is not initialized by default?

What value is stored in the local variable if it is not initialized by default?

What is the command we use to set the `DF` (Direction Flag) bit?

What is the command we use to set the <code>DF</code> (Direction Flag) bit?

When is the `ZF` bit in the `%RFLAGS` register set to 1?

When is the <code>ZF</code> bit in the <code>%RFLAGS</code> register set to 1?

What special instruction replaces the contents of the second operand with the contents of the first operand, filling the remaining bits with zeros?

What special instruction replaces the contents of the second operand with the contents of the first operand, filling the remaining bits with zeros?

Test your understanding of Function Parameters and Function Pointer Parameters.

Introduction to the Course

Memory, Registers, and Simple Arithmetic

Code Optimization

Number Representations

Pointers

Bytes, Words, Double, and Quad Words

Pointers to Memory

Logical Instructions and RIP

Reconstructing a Program with Pointers

Memory and Stacks

Frame Pointer and Local Variables

Function Parameters

More Instructions

Function Pointer Parameters

Summary of Code Disassembly Patterns

x64 Debugging, Disassembly & Reversing Exam

Quiz on Function Parameters and Function Pointer Parameters