tests/tcg/x86_64/noexec.c

   1 #include "../multiarch/noexec.c.inc"
   2
   3 static void *arch_mcontext_pc(const mcontext_t *ctx)
   4 {
   5     return (void *)ctx->gregs[REG_RIP];
   6 }
   7
   8 int arch_mcontext_arg(const mcontext_t *ctx)
   9 {
  10     return ctx->gregs[REG_RDI];
  11 }
  12
  13 static void arch_flush(void *p, int len)
  14 {
  15 }
  16
  17 extern char noexec_1[];
  18 extern char noexec_2[];
  19 extern char noexec_end[];
  20
  21 asm("noexec_1:\n"
  22     "    movq $1,%rdi\n"    /* %rdi is 0 on entry, set 1. */
  23     "noexec_2:\n"
  24     "    movq $2,%rdi\n"    /* %rdi is 0/1; set 2. */
  25     "    ret\n"
  26     "noexec_end:");
  27
  28 int main(void)
  29 {
  30     struct noexec_test noexec_tests[] = {
  31         {
  32             .name = "fallthrough",
  33             .test_code = noexec_1,
  34             .test_len = noexec_end - noexec_1,
  35             .page_ofs = noexec_1 - noexec_2,
  36             .entry_ofs = noexec_1 - noexec_2,
  37             .expected_si_ofs = 0,
  38             .expected_pc_ofs = 0,
  39             .expected_arg = 1,
  40         },
  41         {
  42             .name = "jump",
  43             .test_code = noexec_1,
  44             .test_len = noexec_end - noexec_1,
  45             .page_ofs = noexec_1 - noexec_2,
  46             .entry_ofs = 0,
  47             .expected_si_ofs = 0,
  48             .expected_pc_ofs = 0,
  49             .expected_arg = 0,
  50         },
  51         {
  52             .name = "fallthrough [cross]",
  53             .test_code = noexec_1,
  54             .test_len = noexec_end - noexec_1,
  55             .page_ofs = noexec_1 - noexec_2 - 2,
  56             .entry_ofs = noexec_1 - noexec_2 - 2,
  57             .expected_si_ofs = 0,
  58             .expected_pc_ofs = -2,
  59             .expected_arg = 1,
  60         },
  61         {
  62             .name = "jump [cross]",
  63             .test_code = noexec_1,
  64             .test_len = noexec_end - noexec_1,
  65             .page_ofs = noexec_1 - noexec_2 - 2,
  66             .entry_ofs = -2,
  67             .expected_si_ofs = 0,
  68             .expected_pc_ofs = -2,
  69             .expected_arg = 0,
  70         },
  71     };
  72
  73     return test_noexec(noexec_tests,
  74                        sizeof(noexec_tests) / sizeof(noexec_tests[0]));
  75 }