xref: /kernel/linux/linux-5.10/lib/test_ubsan.c (revision 8c2ecf20) 
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/init.h>
3#include <linux/kernel.h>
4#include <linux/module.h>
5
6typedef void(*test_ubsan_fp)(void);
7
8static void test_ubsan_add_overflow(void)
9{
10	volatile int val = INT_MAX;
11
12	val += 2;
13}
14
15static void test_ubsan_sub_overflow(void)
16{
17	volatile int val = INT_MIN;
18	volatile int val2 = 2;
19
20	val -= val2;
21}
22
23static void test_ubsan_mul_overflow(void)
24{
25	volatile int val = INT_MAX / 2;
26
27	val *= 3;
28}
29
30static void test_ubsan_negate_overflow(void)
31{
32	volatile int val = INT_MIN;
33
34	val = -val;
35}
36
37static void test_ubsan_divrem_overflow(void)
38{
39	volatile int val = 16;
40	volatile int val2 = 0;
41
42	val /= val2;
43}
44
45static void test_ubsan_shift_out_of_bounds(void)
46{
47	volatile int val = -1;
48	int val2 = 10;
49
50	val2 <<= val;
51}
52
53static void test_ubsan_out_of_bounds(void)
54{
55	volatile int i = 4, j = 5;
56	volatile int arr[4];
57
58	arr[j] = i;
59}
60
61static void test_ubsan_load_invalid_value(void)
62{
63	volatile char *dst, *src;
64	bool val, val2, *ptr;
65	char c = 4;
66
67	dst = (char *)&val;
68	src = &c;
69	*dst = *src;
70
71	ptr = &val2;
72	val2 = val;
73}
74
75static void test_ubsan_null_ptr_deref(void)
76{
77	volatile int *ptr = NULL;
78	int val;
79
80	val = *ptr;
81}
82
83static void test_ubsan_misaligned_access(void)
84{
85	volatile char arr[5] __aligned(4) = {1, 2, 3, 4, 5};
86	volatile int *ptr, val = 6;
87
88	ptr = (int *)(arr + 1);
89	*ptr = val;
90}
91
92static const test_ubsan_fp test_ubsan_array[] = {
93	test_ubsan_add_overflow,
94	test_ubsan_sub_overflow,
95	test_ubsan_mul_overflow,
96	test_ubsan_negate_overflow,
97	test_ubsan_divrem_overflow,
98	test_ubsan_shift_out_of_bounds,
99	test_ubsan_out_of_bounds,
100	test_ubsan_load_invalid_value,
101	//test_ubsan_null_ptr_deref, /* exclude it because there is a crash */
102	test_ubsan_misaligned_access,
103};
104
105static int __init test_ubsan_init(void)
106{
107	unsigned int i;
108
109	for (i = 0; i < ARRAY_SIZE(test_ubsan_array); i++)
110		test_ubsan_array[i]();
111
112	(void)test_ubsan_null_ptr_deref; /* to avoid unsed-function warning */
113	return 0;
114}
115module_init(test_ubsan_init);
116
117static void __exit test_ubsan_exit(void)
118{
119	/* do nothing */
120}
121module_exit(test_ubsan_exit);
122
123MODULE_AUTHOR("Jinbum Park <jinb.park7@gmail.com>");
124MODULE_LICENSE("GPL v2");
125