This was used in several Linux drivers (PPPoE if I recall..?) as an EoP exploit - mmap low addresses, then get the kernel to jump to a null pointer. This is one

This was used in several Linux drivers (PPPoE if I recall..?) as an EoP exploit - mmap low addresses, then get the kernel to jump to a null pointer. This is one of the reasons that all addresses <= 0x10000 in Windows NT are invalid, regardless of user/kernel mode.