debug/tst-longjmp_chk.c

   1 /* Basic test to make sure doing a longjmp to a jmpbuf with an invalid sp
   2    is caught by the fortification code.  */
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include <paths.h>
   6 #include <setjmp.h>
   7 #include <signal.h>
   8 #include <stdbool.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12
  13
  14 static int do_test(void);
  15 #define TEST_FUNCTION do_test ()
  16 #include "../test-skeleton.c"
  17
  18
  19 static jmp_buf b;
  20
  21
  22 static void
  23 __attribute__ ((noinline))
  24 f (void)
  25 {
  26   char buf[1000];
  27   asm volatile ("" : "=m" (buf));
  28
  29   if (setjmp (b) != 0)
  30     {
  31       puts ("second longjmp succeeded");
  32       exit (1);
  33     }
  34 }
  35
  36
  37 static bool expected_to_fail;
  38
  39
  40 static void
  41 handler (int sig)
  42 {
  43   if (expected_to_fail)
  44     _exit (0);
  45   else
  46     {
  47       static const char msg[] = "unexpected longjmp failure\n";
  48       TEMP_FAILURE_RETRY (write (STDOUT_FILENO, msg, sizeof (msg) - 1));
  49       _exit (1);
  50     }
  51 }
  52
  53
  54 static int
  55 do_test (void)
  56 {
  57   set_fortify_handler (handler);
  58
  59
  60   expected_to_fail = false;
  61
  62   if (setjmp (b) == 0)
  63     {
  64       longjmp (b, 1);
  65       /* NOTREACHED */
  66       printf ("first longjmp returned\n");
  67       return 1;
  68     }
  69
  70
  71   expected_to_fail = true;
  72
  73   f ();
  74   longjmp (b, 1);
  75
  76   puts ("second longjmp returned");
  77   return 1;
  78 }