DYNAMIC INTERRUPT STACK PROTECTION

摘要

A protection unit of an interrupt stack accessible by a CPU controlled by one software program, for storing and removing stack frame(s), the stack protection unit being coupleable to the stack and the CPU, comprising:
a processor coupled to a first and a second address register;

wherein, when a first stack frame is stored onto the stack and the execution of the software program is suspended by the CPU, responsive to one or more occurring hardware IRQs;
the processing unit is adapted to set one access rule based on the first and second address registers, preventing:
the occurring ISR to be serviced, from accessing a hardware-protected region of the stack, comprising at least the first stack frame and at least one stack frame associated with one or more suspended IRQs.;A processor, a method and a computer program are also claimed.

主权项

1. A protection unit for preventing unauthorized access to at least part of a Last In-First Out memory, referred to as stack, the stack having memory addresses extending between a top address and a bottom address, the stack being accessible by a central processing unit, of a computer system, such as a central processor, CPU, for storing and removing at least one stack frame, the CPU being controllable by one software program, the stack protection unit being operably coupleable to the stack and the CPU, the stack protection unit comprising:
a first and a second address register each adapted to store an address of the stack; and, a processing unit such as a processor operably coupled to the first and second address registers; wherein, when a first stack frame is stored onto the stack and the execution of the software program is suspended by the CPU, responsive to one or more occurring interrupt service requests; the processing unit is adapted to set at least one access rule based on at least the first and second address registers, preventing:
the occurring interrupt service request to be serviced, from accessing a hardware-protected region of the stack, the hardware-protected region comprising at least the first stack frame and at least one stack frame associated with one or more suspended interrupt service requests.