1 /*
2 * Copyright (c) 2018 Intel Corporation
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <ztest.h>
8 #include <zephyr.h>
9
10 #define STACKSIZE 2048
11 #define THREAD_COUNT 64
12 #define VERBOSE 0
13
14 void *last_sp = (void *)0xFFFFFFFF;
15 volatile unsigned int changed;
16
alternate_thread(void)17 void alternate_thread(void)
18 {
19 int i;
20 void *sp_val;
21
22 /* If the stack isn't being randomized then sp_val will never change */
23 sp_val = &i;
24
25 #if VERBOSE
26 printk("stack pointer: %p last: %p\n", sp_val, last_sp);
27 #endif
28
29 if (last_sp != (void *)0xFFFFFFFF && sp_val != last_sp) {
30 changed++;
31 }
32 last_sp = sp_val;
33 }
34
35
36 K_THREAD_STACK_DEFINE(alt_thread_stack_area, STACKSIZE);
37 static struct k_thread alt_thread_data;
38
39 /**
40 * @brief Test stack pointer randomization
41 *
42 * @ingroup kernel_memprotect_tests
43 *
44 */
test_stack_pt_randomization(void)45 void test_stack_pt_randomization(void)
46 {
47 int i, sp_changed;
48 int old_prio = k_thread_priority_get(k_current_get());
49
50 /* Set preemptable priority */
51 k_thread_priority_set(k_current_get(), K_PRIO_PREEMPT(1));
52
53 printk("Test Stack pointer randomization\n");
54
55 /* Start thread */
56 for (i = 0; i < THREAD_COUNT; i++) {
57 k_thread_create(&alt_thread_data, alt_thread_stack_area,
58 STACKSIZE, (k_thread_entry_t)alternate_thread,
59 NULL, NULL, NULL, K_HIGHEST_THREAD_PRIO, 0,
60 K_NO_WAIT);
61 }
62
63
64 printk("stack pointer changed %d times out of %d tests\n",
65 changed, THREAD_COUNT);
66
67 sp_changed = changed;
68 zassert_not_equal(sp_changed, 0, "Stack pointer is not randomized");
69
70 /* Restore priority */
71 k_thread_priority_set(k_current_get(), old_prio);
72 }
73
test_main(void)74 void test_main(void)
75 {
76 ztest_test_suite(stack_pointer_randomness,
77 ztest_1cpu_unit_test(test_stack_pt_randomization));
78 ztest_run_test_suite(stack_pointer_randomness);
79 }
80
