1 #include <sys/cdefs.h> 2 #include <sys/types.h> 3 #include <sys/param.h> 4 #include <sys/kernel.h> 5 #include <sys/systm.h> 6 #include <sys/libkern.h> 7 8 long __stack_chk_guard[8] = {}; 9 void __stack_chk_fail(void); 10 11 void 12 __stack_chk_fail(void) 13 { 14 panic("stack buffer overflow detected; backtrace may be corrupted"); 15 } 16 17 static void 18 __stack_chk_init(void *dummy __unused) 19 { 20 size_t i; 21 long guard[nitems(__stack_chk_guard)]; 22 23 arc4rand(guard, sizeof(guard), 0); 24 for (i = 0; i < nitems(guard); i++) 25 __stack_chk_guard[i] = guard[i]; 26 } 27 SYSINIT(stack_chk, SI_SUB_RANDOM, SI_ORDER_ANY, __stack_chk_init, NULL); 28