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 volatile int i = 4, j = 5, k = -1;
39 volatile char above[4] = { }; /* Protect surrounding memory. */
40 volatile int arr[4];
41 volatile char below[4] = { }; /* Protect surrounding memory. */
42
43 above[0] = below[0];
44
45 UBSAN_TEST(CONFIG_UBSAN_BOUNDS, "above");
46 arr[j] = i;
47
48 UBSAN_TEST(CONFIG_UBSAN_BOUNDS, "below");
49 arr[k] = i;
50 }
51
52 enum ubsan_test_enum {
53 UBSAN_TEST_ZERO = 0,
54 UBSAN_TEST_ONE,
55 UBSAN_TEST_MAX,
56 };
57
test_ubsan_load_invalid_value(void)58 static void test_ubsan_load_invalid_value(void)
59 {
60 volatile char *dst, *src;
61 bool val, val2, *ptr;
62 enum ubsan_test_enum eval, eval2, *eptr;
63 unsigned char c = 0xff;
64
65 UBSAN_TEST(CONFIG_UBSAN_BOOL, "bool");
66 dst = (char *)&val;
67 src = &c;
68 *dst = *src;
69
70 ptr = &val2;
71 val2 = val;
72
73 UBSAN_TEST(CONFIG_UBSAN_ENUM, "enum");
74 dst = (char *)&eval;
75 src = &c;
76 *dst = *src;
77
78 eptr = &eval2;
79 eval2 = eval;
80 }
81
test_ubsan_null_ptr_deref(void)82 static void test_ubsan_null_ptr_deref(void)
83 {
84 volatile int *ptr = NULL;
85 int val;
86
87 UBSAN_TEST(CONFIG_UBSAN_OBJECT_SIZE);
88 val = *ptr;
89 }
90
test_ubsan_misaligned_access(void)91 static void test_ubsan_misaligned_access(void)
92 {
93 volatile char arr[5] __aligned(4) = {1, 2, 3, 4, 5};
94 volatile int *ptr, val = 6;
95
96 UBSAN_TEST(CONFIG_UBSAN_ALIGNMENT);
97 ptr = (int *)(arr + 1);
98 *ptr = val;
99 }
100
test_ubsan_object_size_mismatch(void)101 static void test_ubsan_object_size_mismatch(void)
102 {
103 /* "((aligned(8)))" helps this not into be misaligned for ptr-access. */
104 volatile int val __aligned(8) = 4;
105 volatile long long *ptr, val2;
106
107 UBSAN_TEST(CONFIG_UBSAN_OBJECT_SIZE);
108 ptr = (long long *)&val;
109 val2 = *ptr;
110 }
111
112 static const test_ubsan_fp test_ubsan_array[] = {
113 test_ubsan_shift_out_of_bounds,
114 test_ubsan_out_of_bounds,
115 test_ubsan_load_invalid_value,
116 test_ubsan_misaligned_access,
117 test_ubsan_object_size_mismatch,
118 };
119
120 /* Excluded because they Oops the module. */
121 static const test_ubsan_fp skip_ubsan_array[] = {
122 test_ubsan_divrem_overflow,
123 test_ubsan_null_ptr_deref,
124 };
125
test_ubsan_init(void)126 static int __init test_ubsan_init(void)
127 {
128 unsigned int i;
129
130 for (i = 0; i < ARRAY_SIZE(test_ubsan_array); i++)
131 test_ubsan_array[i]();
132
133 return 0;
134 }
135 module_init(test_ubsan_init);
136
test_ubsan_exit(void)137 static void __exit test_ubsan_exit(void)
138 {
139 /* do nothing */
140 }
141 module_exit(test_ubsan_exit);
142
143 MODULE_AUTHOR("Jinbum Park <jinb.park7@gmail.com>");
144 MODULE_LICENSE("GPL v2");
145