noexec.c (1998B)
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 }