Yea I've read the example at smash the stack and other examples online, but they only show you how to spawn a shell. I wanted to do a simple buffer overflow like the example you have posted, with just a small spin. Instead of spawning a shell, in the vuln.c would hold an uncalled function and exploit.c would exploit the vuln.c and jump to the uncalled function. I know have to find out where the SP starts at and look at the assembly, but I haven't found any examples how to make it jump to a certain part of code. I wanted to see if anyone had a solid example that shows this or detail tutorial that does this.