Buffer Overflow Intro. ©2002, Jedidiah R. Crandall, Susan L. Gerhart, Jan G. Hogle.  http://sfsecurity.pr.erau.edu
All the pieces are in place – one minor error and we’ll see how to hijack the mailroom.

Part of Alice’s instructions to Norman was for him to ask Patty the user for her last name (as a series of numbers on pieces of paper) and store it in a temporary buffer on the stack.  These instructions are encapsulated in a subroutine called GetLastName().