1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
3 #include <linux/kernel.h>
4 #include <linux/module.h>
5
6 typedef void(*test_ubsan_fp)(void);
7
8 #define UBSAN_TEST(config, ...) do { \
9 pr_info("%s " __VA_ARGS__ "%s(%s=%s)\n", __func__, \
10 sizeof(" " __VA_ARGS__) > 2 ? " " : "", \
11 #config, IS_ENABLED(config) ? "y" : "n"); \
12 } while (0)
13
test_ubsan_divrem_overflow(void)14 static void test_ubsan_divrem_overflow(void)
15 {
16 volatile int val = 16;
17 volatile int val2 = 0;
18
19 UBSAN_TEST(CONFIG_UBSAN_DIV_ZERO);
20 val /= val2;
21 }
22
test_ubsan_shift_out_of_bounds(void)23 static void test_ubsan_shift_out_of_bounds(void)
24 {
25 volatile int neg = -1, wrap = 4;
26 int val1 = 10;
27 int val2 = INT_MAX;
28
29 UBSAN_TEST(CONFIG_UBSAN_SHIFT, "negative exponent");
30 val1 <<= neg;
31
32 UBSAN_TEST(CONFIG_UBSAN_SHIFT, "left overflow");
33 val2 <<= wrap;
34 }
35
test_ubsan_out_of_bounds(void)36 static void test_ubsan_out_of_bounds(void)
37 {
38 int i = 4, j = 4, k = -1;
39 volatile struct {
40 char above[4]; /* Protect surrounding memory. */
41 int arr[4];
42 char below[4]; /* Protect surrounding memory. */
43 } data;
44
45 OPTIMIZER_HIDE_VAR(i);
46 OPTIMIZER_HIDE_VAR(j);
47 OPTIMIZER_HIDE_VAR(k);
48
49 UBSAN_TEST(CONFIG_UBSAN_BOUNDS, "above");
50 data.arr[j] = i;
51
52 UBSAN_TEST(CONFIG_UBSAN_BOUNDS, "below");
53 data.arr[k] = i;
54 }
55
56 enum ubsan_test_enum {
57 UBSAN_TEST_ZERO = 0,
58 UBSAN_TEST_ONE,
59 UBSAN_TEST_MAX,
60 };
61
test_ubsan_load_invalid_value(void)62 static void test_ubsan_load_invalid_value(void)
63 {
64 volatile char *dst, *src;
65 bool val, val2, *ptr;
66 enum ubsan_test_enum eval, eval2, *eptr;
67 unsigned char c = 0xff;
68
69 UBSAN_TEST(CONFIG_UBSAN_BOOL, "bool");
70 dst = (char *)&val;
71 src = &c;
72 *dst = *src;
73
74 ptr = &val2;
75 val2 = val;
76
77 UBSAN_TEST(CONFIG_UBSAN_ENUM, "enum");
78 dst = (char *)&eval;
79 src = &c;
80 *dst = *src;
81
82 eptr = &eval2;
83 eval2 = eval;
84 }
85
test_ubsan_misaligned_access(void)86 static void test_ubsan_misaligned_access(void)
87 {
88 volatile char arr[5] __aligned(4) = {1, 2, 3, 4, 5};
89 volatile int *ptr, val = 6;
90
91 UBSAN_TEST(CONFIG_UBSAN_ALIGNMENT);
92 ptr = (int *)(arr + 1);
93 *ptr = val;
94 }
95
96 static const test_ubsan_fp test_ubsan_array[] = {
97 test_ubsan_shift_out_of_bounds,
98 test_ubsan_out_of_bounds,
99 test_ubsan_load_invalid_value,
100 test_ubsan_misaligned_access,
101 };
102
103 /* Excluded because they Oops the module. */
104 static const test_ubsan_fp skip_ubsan_array[] = {
105 test_ubsan_divrem_overflow,
106 };
107
test_ubsan_init(void)108 static int __init test_ubsan_init(void)
109 {
110 unsigned int i;
111
112 for (i = 0; i < ARRAY_SIZE(test_ubsan_array); i++)
113 test_ubsan_array[i]();
114
115 return 0;
116 }
117 module_init(test_ubsan_init);
118
test_ubsan_exit(void)119 static void __exit test_ubsan_exit(void)
120 {
121 /* do nothing */
122 }
123 module_exit(test_ubsan_exit);
124
125 MODULE_AUTHOR("Jinbum Park <jinb.park7@gmail.com>");
126 MODULE_LICENSE("GPL v2");
127