Question

2

How do I enable a buffer overflow?

rated 0 times [ 2] [ 0] / answers: 1 / hits: 7721 / 2 Years ago, mon, march 14, 2022, 12:08:06

I just installed 12.04 (WUBI actually) and I wanted to learn a bit about buffer overflow. Unfortunately when I try to use a function like puts() and gets() in an incorrect manner (that is, to cause a buffer overflow), gcc tells me that it detected smashing the stack and terminate my program.

How do I enable stack overflow?

For more clarity, This is the program:

#include<stdio.h>



CanNeverExecute()

{

    printf("I can never execute

");

    exit(0);

}



GetInput()

{

    char buffer[8];



    gets(buffer);

    puts(buffer);

}



main()

{

    GetInput();



    return 0;

}

Answers

Only authorized users can answer the question. Please sign in first, or register a free account.

tocklftime

Add To Favorites

Follow

Total Points: 110

Total Questions: 109

Total Answers: 100

Location: Mayotte

Member since Mon, Sep 12, 2022

2 Years ago

tocklftime questions

1 how to set option COMPRESS in /etc/initramfs-tools

Wed, Feb 1, 23, 21:50, 1 Year ago

1 Accidentally hit ctrl+alt+f12 and then ctrl+alt+f2 and rebooted

Fri, Nov 12, 21, 17:17, 3 Years ago

1 Why am I only able to boot ubuntu from recovery mode?

Tue, Oct 4, 22, 21:42, 2 Years ago

1 How to automatically put text or job commands into `crontab` file?

Thu, Oct 13, 22, 12:43, 2 Years ago

1 Battery unknown, stays at 0% but holds battery fine

Sun, Jul 25, 21, 10:43, 3 Years ago

View All

answered 2 Years ago azaaburge · Accepted Answer

I don't think what you are doing is a stack overflow. That is what happens when you recurse too deeply into a function, causing you to run out of stack frames.

int main(int argc, char *argv[]) {

    return main(argc, argv);

}

What you are trying to achieve is a buffer overflow on the stack. I think you are hoping to write to the return address and then make it call CanNeverExecute.

Then you get stack smashing detected, from gcc's stack protector. You can disable it using gcc -fno-stack-protector. Of course, don't ever do that with programs you intend on running for production.