Something that helps prevent buffer overflows: Stackgap


   Before               With Stackgap  (3 different program executions)

Wastes at most 1 page of real memory
Admin can adjust range:   Typically 64KB - 256KB
                                            256KB = 1/32768 chance of success
This is a 3-line change to the kernel.

Why have all the other vendors not picked up on this??