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 14 static void test_ubsan_add_overflow(void) 15 { 16 volatile int val = INT_MAX; 17 18 UBSAN_TEST(CONFIG_UBSAN_INTEGER_WRAP); 19 val += 2; 20 } 21 22 static void test_ubsan_sub_overflow(void) 23 { 24 volatile int val = INT_MIN; 25 volatile int val2 = 2; 26 27 UBSAN_TEST(CONFIG_UBSAN_INTEGER_WRAP); 28 val -= val2; 29 } 30 31 static void test_ubsan_mul_overflow(void) 32 { 33 volatile int val = INT_MAX / 2; 34 35 UBSAN_TEST(CONFIG_UBSAN_INTEGER_WRAP); 36 val *= 3; 37 } 38 39 static void test_ubsan_negate_overflow(void) 40 { 41 volatile int val = INT_MIN; 42 43 UBSAN_TEST(CONFIG_UBSAN_INTEGER_WRAP); 44 val = -val; 45 } 46 47 static void test_ubsan_divrem_overflow(void) 48 { 49 volatile int val = 16; 50 volatile int val2 = 0; 51 52 UBSAN_TEST(CONFIG_UBSAN_DIV_ZERO); 53 val /= val2; 54 } 55 56 static void test_ubsan_truncate_signed(void) 57 { 58 volatile long val = LONG_MAX; 59 volatile int val2 = 0; 60 61 UBSAN_TEST(CONFIG_UBSAN_INTEGER_WRAP); 62 val2 = val; 63 } 64 65 static void test_ubsan_shift_out_of_bounds(void) 66 { 67 volatile int neg = -1, wrap = 4; 68 volatile int val1 = 10; 69 volatile int val2 = INT_MAX; 70 71 UBSAN_TEST(CONFIG_UBSAN_SHIFT, "negative exponent"); 72 val1 <<= neg; 73 74 UBSAN_TEST(CONFIG_UBSAN_SHIFT, "left overflow"); 75 val2 <<= wrap; 76 } 77 78 static void test_ubsan_out_of_bounds(void) 79 { 80 volatile int i = 4, j = 5, k = -1; 81 volatile char above[4] = { }; /* Protect surrounding memory. */ 82 volatile int arr[4]; 83 volatile char below[4] = { }; /* Protect surrounding memory. */ 84 85 above[0] = below[0]; 86 87 UBSAN_TEST(CONFIG_UBSAN_BOUNDS, "above"); 88 arr[j] = i; 89 90 UBSAN_TEST(CONFIG_UBSAN_BOUNDS, "below"); 91 arr[k] = i; 92 } 93 94 enum ubsan_test_enum { 95 UBSAN_TEST_ZERO = 0, 96 UBSAN_TEST_ONE, 97 UBSAN_TEST_MAX, 98 }; 99 100 static void test_ubsan_load_invalid_value(void) 101 { 102 volatile char *dst, *src; 103 bool val, val2, *ptr; 104 enum ubsan_test_enum eval, eval2, *eptr; 105 unsigned char c = 0xff; 106 107 UBSAN_TEST(CONFIG_UBSAN_BOOL, "bool"); 108 dst = (char *)&val; 109 src = &c; 110 *dst = *src; 111 112 ptr = &val2; 113 val2 = val; 114 115 UBSAN_TEST(CONFIG_UBSAN_ENUM, "enum"); 116 dst = (char *)&eval; 117 src = &c; 118 *dst = *src; 119 120 eptr = &eval2; 121 eval2 = eval; 122 } 123 124 static void test_ubsan_misaligned_access(void) 125 { 126 volatile char arr[5] __aligned(4) = {1, 2, 3, 4, 5}; 127 volatile int *ptr, val = 6; 128 129 UBSAN_TEST(CONFIG_UBSAN_ALIGNMENT); 130 ptr = (int *)(arr + 1); 131 *ptr = val; 132 } 133 134 static const test_ubsan_fp test_ubsan_array[] = { 135 test_ubsan_add_overflow, 136 test_ubsan_sub_overflow, 137 test_ubsan_mul_overflow, 138 test_ubsan_negate_overflow, 139 test_ubsan_truncate_signed, 140 test_ubsan_shift_out_of_bounds, 141 test_ubsan_out_of_bounds, 142 test_ubsan_load_invalid_value, 143 test_ubsan_misaligned_access, 144 }; 145 146 /* Excluded because they Oops the module. */ 147 static __used const test_ubsan_fp skip_ubsan_array[] = { 148 test_ubsan_divrem_overflow, 149 }; 150 151 static int __init test_ubsan_init(void) 152 { 153 unsigned int i; 154 155 for (i = 0; i < ARRAY_SIZE(test_ubsan_array); i++) 156 test_ubsan_array[i](); 157 158 return 0; 159 } 160 module_init(test_ubsan_init); 161 162 static void __exit test_ubsan_exit(void) 163 { 164 /* do nothing */ 165 } 166 module_exit(test_ubsan_exit); 167 168 MODULE_AUTHOR("Jinbum Park <jinb.park7@gmail.com>"); 169 MODULE_DESCRIPTION("UBSAN unit test"); 170 MODULE_LICENSE("GPL v2"); 171