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-rw-r--r--lib/test_overflow.c287
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diff --git a/lib/test_overflow.c b/lib/test_overflow.c
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1// SPDX-License-Identifier: GPL-2.0 OR MIT
2/*
3 * Test cases for arithmetic overflow checks.
4 */
5#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
6
7#include <linux/init.h>
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/overflow.h>
11#include <linux/types.h>
12
13#define DEFINE_TEST_ARRAY(t) \
14 static const struct test_ ## t { \
15 t a, b; \
16 t sum, diff, prod; \
17 bool s_of, d_of, p_of; \
18 } t ## _tests[] __initconst
19
20DEFINE_TEST_ARRAY(u8) = {
21 {0, 0, 0, 0, 0, false, false, false},
22 {1, 1, 2, 0, 1, false, false, false},
23 {0, 1, 1, U8_MAX, 0, false, true, false},
24 {1, 0, 1, 1, 0, false, false, false},
25 {0, U8_MAX, U8_MAX, 1, 0, false, true, false},
26 {U8_MAX, 0, U8_MAX, U8_MAX, 0, false, false, false},
27 {1, U8_MAX, 0, 2, U8_MAX, true, true, false},
28 {U8_MAX, 1, 0, U8_MAX-1, U8_MAX, true, false, false},
29 {U8_MAX, U8_MAX, U8_MAX-1, 0, 1, true, false, true},
30
31 {U8_MAX, U8_MAX-1, U8_MAX-2, 1, 2, true, false, true},
32 {U8_MAX-1, U8_MAX, U8_MAX-2, U8_MAX, 2, true, true, true},
33
34 {1U << 3, 1U << 3, 1U << 4, 0, 1U << 6, false, false, false},
35 {1U << 4, 1U << 4, 1U << 5, 0, 0, false, false, true},
36 {1U << 4, 1U << 3, 3*(1U << 3), 1U << 3, 1U << 7, false, false, false},
37 {1U << 7, 1U << 7, 0, 0, 0, true, false, true},
38
39 {48, 32, 80, 16, 0, false, false, true},
40 {128, 128, 0, 0, 0, true, false, true},
41 {123, 234, 101, 145, 110, true, true, true},
42};
43DEFINE_TEST_ARRAY(u16) = {
44 {0, 0, 0, 0, 0, false, false, false},
45 {1, 1, 2, 0, 1, false, false, false},
46 {0, 1, 1, U16_MAX, 0, false, true, false},
47 {1, 0, 1, 1, 0, false, false, false},
48 {0, U16_MAX, U16_MAX, 1, 0, false, true, false},
49 {U16_MAX, 0, U16_MAX, U16_MAX, 0, false, false, false},
50 {1, U16_MAX, 0, 2, U16_MAX, true, true, false},
51 {U16_MAX, 1, 0, U16_MAX-1, U16_MAX, true, false, false},
52 {U16_MAX, U16_MAX, U16_MAX-1, 0, 1, true, false, true},
53
54 {U16_MAX, U16_MAX-1, U16_MAX-2, 1, 2, true, false, true},
55 {U16_MAX-1, U16_MAX, U16_MAX-2, U16_MAX, 2, true, true, true},
56
57 {1U << 7, 1U << 7, 1U << 8, 0, 1U << 14, false, false, false},
58 {1U << 8, 1U << 8, 1U << 9, 0, 0, false, false, true},
59 {1U << 8, 1U << 7, 3*(1U << 7), 1U << 7, 1U << 15, false, false, false},
60 {1U << 15, 1U << 15, 0, 0, 0, true, false, true},
61
62 {123, 234, 357, 65425, 28782, false, true, false},
63 {1234, 2345, 3579, 64425, 10146, false, true, true},
64};
65DEFINE_TEST_ARRAY(u32) = {
66 {0, 0, 0, 0, 0, false, false, false},
67 {1, 1, 2, 0, 1, false, false, false},
68 {0, 1, 1, U32_MAX, 0, false, true, false},
69 {1, 0, 1, 1, 0, false, false, false},
70 {0, U32_MAX, U32_MAX, 1, 0, false, true, false},
71 {U32_MAX, 0, U32_MAX, U32_MAX, 0, false, false, false},
72 {1, U32_MAX, 0, 2, U32_MAX, true, true, false},
73 {U32_MAX, 1, 0, U32_MAX-1, U32_MAX, true, false, false},
74 {U32_MAX, U32_MAX, U32_MAX-1, 0, 1, true, false, true},
75
76 {U32_MAX, U32_MAX-1, U32_MAX-2, 1, 2, true, false, true},
77 {U32_MAX-1, U32_MAX, U32_MAX-2, U32_MAX, 2, true, true, true},
78
79 {1U << 15, 1U << 15, 1U << 16, 0, 1U << 30, false, false, false},
80 {1U << 16, 1U << 16, 1U << 17, 0, 0, false, false, true},
81 {1U << 16, 1U << 15, 3*(1U << 15), 1U << 15, 1U << 31, false, false, false},
82 {1U << 31, 1U << 31, 0, 0, 0, true, false, true},
83
84 {-2U, 1U, -1U, -3U, -2U, false, false, false},
85 {-4U, 5U, 1U, -9U, -20U, true, false, true},
86};
87
88DEFINE_TEST_ARRAY(u64) = {
89 {0, 0, 0, 0, 0, false, false, false},
90 {1, 1, 2, 0, 1, false, false, false},
91 {0, 1, 1, U64_MAX, 0, false, true, false},
92 {1, 0, 1, 1, 0, false, false, false},
93 {0, U64_MAX, U64_MAX, 1, 0, false, true, false},
94 {U64_MAX, 0, U64_MAX, U64_MAX, 0, false, false, false},
95 {1, U64_MAX, 0, 2, U64_MAX, true, true, false},
96 {U64_MAX, 1, 0, U64_MAX-1, U64_MAX, true, false, false},
97 {U64_MAX, U64_MAX, U64_MAX-1, 0, 1, true, false, true},
98
99 {U64_MAX, U64_MAX-1, U64_MAX-2, 1, 2, true, false, true},
100 {U64_MAX-1, U64_MAX, U64_MAX-2, U64_MAX, 2, true, true, true},
101
102 {1ULL << 31, 1ULL << 31, 1ULL << 32, 0, 1ULL << 62, false, false, false},
103 {1ULL << 32, 1ULL << 32, 1ULL << 33, 0, 0, false, false, true},
104 {1ULL << 32, 1ULL << 31, 3*(1ULL << 31), 1ULL << 31, 1ULL << 63, false, false, false},
105 {1ULL << 63, 1ULL << 63, 0, 0, 0, true, false, true},
106 {1000000000ULL /* 10^9 */, 10000000000ULL /* 10^10 */,
107 11000000000ULL, 18446744064709551616ULL, 10000000000000000000ULL,
108 false, true, false},
109 {-15ULL, 10ULL, -5ULL, -25ULL, -150ULL, false, false, true},
110};
111
112DEFINE_TEST_ARRAY(s8) = {
113 {0, 0, 0, 0, 0, false, false, false},
114
115 {0, S8_MAX, S8_MAX, -S8_MAX, 0, false, false, false},
116 {S8_MAX, 0, S8_MAX, S8_MAX, 0, false, false, false},
117 {0, S8_MIN, S8_MIN, S8_MIN, 0, false, true, false},
118 {S8_MIN, 0, S8_MIN, S8_MIN, 0, false, false, false},
119
120 {-1, S8_MIN, S8_MAX, S8_MAX, S8_MIN, true, false, true},
121 {S8_MIN, -1, S8_MAX, -S8_MAX, S8_MIN, true, false, true},
122 {-1, S8_MAX, S8_MAX-1, S8_MIN, -S8_MAX, false, false, false},
123 {S8_MAX, -1, S8_MAX-1, S8_MIN, -S8_MAX, false, true, false},
124 {-1, -S8_MAX, S8_MIN, S8_MAX-1, S8_MAX, false, false, false},
125 {-S8_MAX, -1, S8_MIN, S8_MIN+2, S8_MAX, false, false, false},
126
127 {1, S8_MIN, -S8_MAX, -S8_MAX, S8_MIN, false, true, false},
128 {S8_MIN, 1, -S8_MAX, S8_MAX, S8_MIN, false, true, false},
129 {1, S8_MAX, S8_MIN, S8_MIN+2, S8_MAX, true, false, false},
130 {S8_MAX, 1, S8_MIN, S8_MAX-1, S8_MAX, true, false, false},
131
132 {S8_MIN, S8_MIN, 0, 0, 0, true, false, true},
133 {S8_MAX, S8_MAX, -2, 0, 1, true, false, true},
134
135 {-4, -32, -36, 28, -128, false, false, true},
136 {-4, 32, 28, -36, -128, false, false, false},
137};
138
139DEFINE_TEST_ARRAY(s16) = {
140 {0, 0, 0, 0, 0, false, false, false},
141
142 {0, S16_MAX, S16_MAX, -S16_MAX, 0, false, false, false},
143 {S16_MAX, 0, S16_MAX, S16_MAX, 0, false, false, false},
144 {0, S16_MIN, S16_MIN, S16_MIN, 0, false, true, false},
145 {S16_MIN, 0, S16_MIN, S16_MIN, 0, false, false, false},
146
147 {-1, S16_MIN, S16_MAX, S16_MAX, S16_MIN, true, false, true},
148 {S16_MIN, -1, S16_MAX, -S16_MAX, S16_MIN, true, false, true},
149 {-1, S16_MAX, S16_MAX-1, S16_MIN, -S16_MAX, false, false, false},
150 {S16_MAX, -1, S16_MAX-1, S16_MIN, -S16_MAX, false, true, false},
151 {-1, -S16_MAX, S16_MIN, S16_MAX-1, S16_MAX, false, false, false},
152 {-S16_MAX, -1, S16_MIN, S16_MIN+2, S16_MAX, false, false, false},
153
154 {1, S16_MIN, -S16_MAX, -S16_MAX, S16_MIN, false, true, false},
155 {S16_MIN, 1, -S16_MAX, S16_MAX, S16_MIN, false, true, false},
156 {1, S16_MAX, S16_MIN, S16_MIN+2, S16_MAX, true, false, false},
157 {S16_MAX, 1, S16_MIN, S16_MAX-1, S16_MAX, true, false, false},
158
159 {S16_MIN, S16_MIN, 0, 0, 0, true, false, true},
160 {S16_MAX, S16_MAX, -2, 0, 1, true, false, true},
161};
162DEFINE_TEST_ARRAY(s32) = {
163 {0, 0, 0, 0, 0, false, false, false},
164
165 {0, S32_MAX, S32_MAX, -S32_MAX, 0, false, false, false},
166 {S32_MAX, 0, S32_MAX, S32_MAX, 0, false, false, false},
167 {0, S32_MIN, S32_MIN, S32_MIN, 0, false, true, false},
168 {S32_MIN, 0, S32_MIN, S32_MIN, 0, false, false, false},
169
170 {-1, S32_MIN, S32_MAX, S32_MAX, S32_MIN, true, false, true},
171 {S32_MIN, -1, S32_MAX, -S32_MAX, S32_MIN, true, false, true},
172 {-1, S32_MAX, S32_MAX-1, S32_MIN, -S32_MAX, false, false, false},
173 {S32_MAX, -1, S32_MAX-1, S32_MIN, -S32_MAX, false, true, false},
174 {-1, -S32_MAX, S32_MIN, S32_MAX-1, S32_MAX, false, false, false},
175 {-S32_MAX, -1, S32_MIN, S32_MIN+2, S32_MAX, false, false, false},
176
177 {1, S32_MIN, -S32_MAX, -S32_MAX, S32_MIN, false, true, false},
178 {S32_MIN, 1, -S32_MAX, S32_MAX, S32_MIN, false, true, false},
179 {1, S32_MAX, S32_MIN, S32_MIN+2, S32_MAX, true, false, false},
180 {S32_MAX, 1, S32_MIN, S32_MAX-1, S32_MAX, true, false, false},
181
182 {S32_MIN, S32_MIN, 0, 0, 0, true, false, true},
183 {S32_MAX, S32_MAX, -2, 0, 1, true, false, true},
184};
185DEFINE_TEST_ARRAY(s64) = {
186 {0, 0, 0, 0, 0, false, false, false},
187
188 {0, S64_MAX, S64_MAX, -S64_MAX, 0, false, false, false},
189 {S64_MAX, 0, S64_MAX, S64_MAX, 0, false, false, false},
190 {0, S64_MIN, S64_MIN, S64_MIN, 0, false, true, false},
191 {S64_MIN, 0, S64_MIN, S64_MIN, 0, false, false, false},
192
193 {-1, S64_MIN, S64_MAX, S64_MAX, S64_MIN, true, false, true},
194 {S64_MIN, -1, S64_MAX, -S64_MAX, S64_MIN, true, false, true},
195 {-1, S64_MAX, S64_MAX-1, S64_MIN, -S64_MAX, false, false, false},
196 {S64_MAX, -1, S64_MAX-1, S64_MIN, -S64_MAX, false, true, false},
197 {-1, -S64_MAX, S64_MIN, S64_MAX-1, S64_MAX, false, false, false},
198 {-S64_MAX, -1, S64_MIN, S64_MIN+2, S64_MAX, false, false, false},
199
200 {1, S64_MIN, -S64_MAX, -S64_MAX, S64_MIN, false, true, false},
201 {S64_MIN, 1, -S64_MAX, S64_MAX, S64_MIN, false, true, false},
202 {1, S64_MAX, S64_MIN, S64_MIN+2, S64_MAX, true, false, false},
203 {S64_MAX, 1, S64_MIN, S64_MAX-1, S64_MAX, true, false, false},
204
205 {S64_MIN, S64_MIN, 0, 0, 0, true, false, true},
206 {S64_MAX, S64_MAX, -2, 0, 1, true, false, true},
207
208 {-1, -1, -2, 0, 1, false, false, false},
209 {-1, -128, -129, 127, 128, false, false, false},
210 {-128, -1, -129, -127, 128, false, false, false},
211 {0, -S64_MAX, -S64_MAX, S64_MAX, 0, false, false, false},
212};
213
214#define DEFINE_TEST_FUNC(t, fmt) \
215static void __init do_test_ ## t(const struct test_ ## t *p) \
216{ \
217 t r; \
218 bool of; \
219 \
220 of = check_add_overflow(p->a, p->b, &r); \
221 if (of != p->s_of) \
222 pr_warn("expected "fmt" + "fmt" to%s overflow (type %s)\n", \
223 p->a, p->b, p->s_of ? "" : " not", #t); \
224 if (r != p->sum) \
225 pr_warn("expected "fmt" + "fmt" == "fmt", got "fmt" (type %s)\n", \
226 p->a, p->b, p->sum, r, #t); \
227 \
228 of = check_sub_overflow(p->a, p->b, &r); \
229 if (of != p->d_of) \
230 pr_warn("expected "fmt" - "fmt" to%s overflow (type %s)\n", \
231 p->a, p->b, p->s_of ? "" : " not", #t); \
232 if (r != p->diff) \
233 pr_warn("expected "fmt" - "fmt" == "fmt", got "fmt" (type %s)\n", \
234 p->a, p->b, p->diff, r, #t); \
235 \
236 of = check_mul_overflow(p->a, p->b, &r); \
237 if (of != p->p_of) \
238 pr_warn("expected "fmt" * "fmt" to%s overflow (type %s)\n", \
239 p->a, p->b, p->p_of ? "" : " not", #t); \
240 if (r != p->prod) \
241 pr_warn("expected "fmt" * "fmt" == "fmt", got "fmt" (type %s)\n", \
242 p->a, p->b, p->prod, r, #t); \
243} \
244 \
245static void __init test_ ## t ## _overflow(void) { \
246 unsigned i; \
247 \
248 pr_info("%-3s: %zu tests\n", #t, ARRAY_SIZE(t ## _tests)); \
249 for (i = 0; i < ARRAY_SIZE(t ## _tests); ++i) \
250 do_test_ ## t(&t ## _tests[i]); \
251}
252
253DEFINE_TEST_FUNC(u8, "%d");
254DEFINE_TEST_FUNC(s8, "%d");
255DEFINE_TEST_FUNC(u16, "%d");
256DEFINE_TEST_FUNC(s16, "%d");
257DEFINE_TEST_FUNC(u32, "%u");
258DEFINE_TEST_FUNC(s32, "%d");
259#if BITS_PER_LONG == 64
260DEFINE_TEST_FUNC(u64, "%llu");
261DEFINE_TEST_FUNC(s64, "%lld");
262#endif
263
264static int __init test_overflow(void)
265{
266 test_u8_overflow();
267 test_s8_overflow();
268 test_u16_overflow();
269 test_s16_overflow();
270 test_u32_overflow();
271 test_s32_overflow();
272#if BITS_PER_LONG == 64
273 test_u64_overflow();
274 test_s64_overflow();
275#endif
276
277 pr_info("done\n");
278
279 return 0;
280}
281
282static void __exit test_module_exit(void)
283{ }
284
285module_init(test_overflow);
286module_exit(test_module_exit);
287MODULE_LICENSE("Dual MIT/GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-26 11:49:58 -0400