Feature Specific Control Flow Checking in COTS-Based Embedded Systems

While the Control Flow Checking (CFC) methods are using the ordinary instruction set and general Arithmetic and Logic Unit (ALU) features to protect the programs against the transient faults, this paper presents a new kind of CFC method, called feature specific CFC. The idea behind this method is using a specific internal hardware in modern processors which provides the ability to monitor internal various parameters of the program. This method is a pure software method and the external hardware overhead is zero. Other overheads have been measured experimentally by executing the workloads on a Pentium system. The execution time overhead is between 42% and 67% and the program size overhead is between 5% and 10% for different workload programs. This method is analytically evaluated based on seven different fault models. The results show that the error detection coverage varies between 98.05% and 98.65% depending on the different workload programs.