Fpw On The Stack Overflow Detection

In the past ten years , stack overflow has become one of most common attacks . Smashing stack is a kind of systemly attack ,which usually write overlong contents in application frame in order to change the control flow to invader.Three means exists in current defencing the overrun of stack: overwriting contents in stack with too long arguments is not allowed ; overwriting is allowed but unauthorized change of control flow is not allowed; change of control flow is allowed but execution of injected code is prevented.We detect stack overflow by monitoring the Previous Frame Pointer. Such comes the tool FPW(Frame Pointer Watcher). It uses different zones named Usu-Prefrm Zone and Jmp-Prefrm Zone to record changing of the Previous Frame Pointer in stack . Compared with Stack Guard and RAD , FPW has more efficent performance, same safety and less memory cost.