tests/nxheap.c

   1 #include <bsdtests.h>
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4
   5 char *heap;
   6 volatile int pass;
   7 sigjmp_buf jbuf;
   8
   9 void
  10 action(int signo, struct __siginfo *info, void *uap __attribute__((unused)))
  11 {
  12         if (info) {
  13                 pass = (signo == SIGBUS && info->si_addr == heap);
  14         }
  15         return siglongjmp(jbuf, 0);
  16 }
  17
  18 int
  19 main(void)
  20 {
  21         int ret;
  22
  23         struct sigaction sa = {
  24                 .__sigaction_u.__sa_sigaction = action,
  25                 .sa_flags = SA_SIGINFO,
  26         };
  27
  28         test_start("Non-executable heap");
  29
  30         ret = sigaction(SIGBUS, &sa, NULL);
  31         assert(ret == 0);
  32         test_long("sigaction", ret, 0);
  33
  34         if (sigsetjmp(jbuf, 0)) {
  35                 // PASS
  36                 test_long("SIGBUS", 1, 1);
  37                 test_stop();
  38                 return EXIT_FAILURE;
  39         }
  40
  41         heap = malloc(1);
  42         test_ptr_notnull("malloc", heap);
  43
  44         *heap = 0xc3; // retq
  45         ((void (*)(void))heap)(); // call *%eax
  46
  47         // FAIL
  48         test_long("SIGBUS", 0, 1);
  49
  50         test_stop();
  51
  52         return EXIT_SUCCESS;
  53 }