vulpkg1 - contains example of overwriting pointer for special privileges
          (this uses a filename pointer with /root/.rhosts as the example)
vulpkg2 - contains example of overwriting a function pointer to execute a
          special function (i.e. system()) in the PLT
vulpkg3 - this demonstrates overwriting a function pointer to reflect back
          to argv, executing shellcode passed as an argument
vulpkg4 - overwritings a pointer into a jmp_buf, fits in theme of vulpkg3
