How to write a sample code that will crash and produce dump file?

Question

I started learned windbg and I found this good post How to use WinDbg to analyze the crash dump for VC++ application?

Now I want to follow the instructions and do it

Answer 1

I used the code below when testing out WinDbg some time ago.

• The code below works and will generate a crash dump
• There are two functions so that you can see a stack trace with an obvious chain of functions.
• To find the crash dumps, search for *.dmp or *.mdmp in C:\Users
• It's probably best to let the OS generate the dump for you. This is probably how most of the real crash dumps you see will be generated.
• The code works by first allocating 1 KiB of memory, then writing both it and the following 1 KiB with a recognizable hexadecimal value. This usually hits a page of memory marked by the OS as non-writeable, which will trigger the crash.

---

#include "stdafx.h"
#include "stdio.h"
#include "malloc.h"

void Function2(int * ptr2)
{
    for(int i=0; i < (2 * 1024); i++)
    {
        *ptr2++ = 0xCAFECAFE;
    }
}

void Function1()
{
    int * ptr1 = (int *)malloc(1024 * sizeof(int));

    Function2(ptr1);
}

int _tmain(int argc, _TCHAR* argv[])
{
    printf("Press enter to allocate and corrupt.\r\n");
    getc(stdin);

    printf("Allocating and corrupting...\r\n");
    Function1();

    printf("Done.  Press enter to exit process.\r\n");
    getc(stdin);

    return 0;
}