Fork Bomb Linux - Shell/Bash

Fork bomb is a malicious program that can cause a denial-of-service attack on a computer system. It works by rapidly creating a large number of child processes which can overwhelm the system resources and cause the system to crash. In this article, we will discuss how to create a fork bomb using the shell/Bash scripting language in Linux.

How does Fork Bomb work?

Fork bomb works by continuously creating child processes using the fork() system call. Each child process created by fork() has its own address space but shares the same code and data segments as the parent process. This means that the child process can execute the same code as the parent process but has a separate memory space.

When a fork bomb is executed, it creates a large number of child processes, which in turn create their own child processes, and so on. This process continues until the system runs out of resources, causing the system to crash or become unresponsive.

Creating a Fork Bomb in Shell/Bash

To create a fork bomb in Shell/Bash, we can use a simple script that uses the while loop and the fork() system call. Here's an example:

#!/bin/bash

:(){ :|:& };:

Let's break down this script:

• The : character is a function name in Bash. In this script, we create a function called :.
• The function definition starts with (){ and ends with };. This is where we define the body of the function.
• Inside the function, we use recursion to call the function itself. :|: is a shorthand way of calling the function recursively.
• The & character sends the command to the background and allows the script to continue executing.
• The final : character calls the : function, starting the fork bomb.

Running the Fork Bomb

To run the fork bomb, simply save the script to a file (e.g. forkbomb.sh) and make it executable by running chmod +x forkbomb.sh. Then, execute the script by running ./forkbomb.sh.

Note that running the fork bomb can cause your system to crash or become unresponsive. Use it with caution and only on systems that you have permission to test on.

Conclusion

In this article, we discussed how fork bomb works and how to create a fork bomb using the shell/Bash scripting language in Linux. It is important to note that fork bomb is a malicious program and should not be used to harm computer systems. Use it with caution and only for testing purposes.