The Study of Register’s Window Exception and Vulnerability Analysis Based on SPARC V8
The processor based on SPARC V8 often cause trap of the overlapping windows: a save instruction attempted to cause the current window pointer (CWP) to point to an invalid window in the window invalid mask register (WIM), then the Window_Overflow trap occurs. A restore or rett instruction attempted to cause the current window pointer (CWP) to point to an invalid window in the window invalid mask register (WIM), then the Window_Underflow trap occurs. Stack data structure storages the contents of the window and releases the overflow one to handle the exceptions of the overlapping windows. Through the stack overflow vulnerability analysis, completed the code layer attacks. Finally, based on the theoretical analysis of vulnerabilities, proposed solutions stack overflow defense programs. Tested and verified the feasibility of the program based on the SPARC V8 processor as AT697F.