aboutsummaryrefslogtreecommitdiffstats
path: root/lib/test_overflow.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/test_overflow.c')
-rw-r--r--lib/test_overflow.c417
1 files changed, 417 insertions, 0 deletions
diff --git a/lib/test_overflow.c b/lib/test_overflow.c
new file mode 100644
index 000000000000..aecbbb217305
--- /dev/null
+++ b/lib/test_overflow.c
@@ -0,0 +1,417 @@
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/device.h>
8#include <linux/init.h>
9#include <linux/kernel.h>
10#include <linux/mm.h>
11#include <linux/module.h>
12#include <linux/overflow.h>
13#include <linux/slab.h>
14#include <linux/types.h>
15#include <linux/vmalloc.h>
16
17#define DEFINE_TEST_ARRAY(t) \
18 static const struct test_ ## t { \
19 t a, b; \
20 t sum, diff, prod; \
21 bool s_of, d_of, p_of; \
22 } t ## _tests[] __initconst
23
24DEFINE_TEST_ARRAY(u8) = {
25 {0, 0, 0, 0, 0, false, false, false},
26 {1, 1, 2, 0, 1, false, false, false},
27 {0, 1, 1, U8_MAX, 0, false, true, false},
28 {1, 0, 1, 1, 0, false, false, false},
29 {0, U8_MAX, U8_MAX, 1, 0, false, true, false},
30 {U8_MAX, 0, U8_MAX, U8_MAX, 0, false, false, false},
31 {1, U8_MAX, 0, 2, U8_MAX, true, true, false},
32 {U8_MAX, 1, 0, U8_MAX-1, U8_MAX, true, false, false},
33 {U8_MAX, U8_MAX, U8_MAX-1, 0, 1, true, false, true},
34
35 {U8_MAX, U8_MAX-1, U8_MAX-2, 1, 2, true, false, true},
36 {U8_MAX-1, U8_MAX, U8_MAX-2, U8_MAX, 2, true, true, true},
37
38 {1U << 3, 1U << 3, 1U << 4, 0, 1U << 6, false, false, false},
39 {1U << 4, 1U << 4, 1U << 5, 0, 0, false, false, true},
40 {1U << 4, 1U << 3, 3*(1U << 3), 1U << 3, 1U << 7, false, false, false},
41 {1U << 7, 1U << 7, 0, 0, 0, true, false, true},
42
43 {48, 32, 80, 16, 0, false, false, true},
44 {128, 128, 0, 0, 0, true, false, true},
45 {123, 234, 101, 145, 110, true, true, true},
46};
47DEFINE_TEST_ARRAY(u16) = {
48 {0, 0, 0, 0, 0, false, false, false},
49 {1, 1, 2, 0, 1, false, false, false},
50 {0, 1, 1, U16_MAX, 0, false, true, false},
51 {1, 0, 1, 1, 0, false, false, false},
52 {0, U16_MAX, U16_MAX, 1, 0, false, true, false},
53 {U16_MAX, 0, U16_MAX, U16_MAX, 0, false, false, false},
54 {1, U16_MAX, 0, 2, U16_MAX, true, true, false},
55 {U16_MAX, 1, 0, U16_MAX-1, U16_MAX, true, false, false},
56 {U16_MAX, U16_MAX, U16_MAX-1, 0, 1, true, false, true},
57
58 {U16_MAX, U16_MAX-1, U16_MAX-2, 1, 2, true, false, true},
59 {U16_MAX-1, U16_MAX, U16_MAX-2, U16_MAX, 2, true, true, true},
60
61 {1U << 7, 1U << 7, 1U << 8, 0, 1U << 14, false, false, false},
62 {1U << 8, 1U << 8, 1U << 9, 0, 0, false, false, true},
63 {1U << 8, 1U << 7, 3*(1U << 7), 1U << 7, 1U << 15, false, false, false},
64 {1U << 15, 1U << 15, 0, 0, 0, true, false, true},
65
66 {123, 234, 357, 65425, 28782, false, true, false},
67 {1234, 2345, 3579, 64425, 10146, false, true, true},
68};
69DEFINE_TEST_ARRAY(u32) = {
70 {0, 0, 0, 0, 0, false, false, false},
71 {1, 1, 2, 0, 1, false, false, false},
72 {0, 1, 1, U32_MAX, 0, false, true, false},
73 {1, 0, 1, 1, 0, false, false, false},
74 {0, U32_MAX, U32_MAX, 1, 0, false, true, false},
75 {U32_MAX, 0, U32_MAX, U32_MAX, 0, false, false, false},
76 {1, U32_MAX, 0, 2, U32_MAX, true, true, false},
77 {U32_MAX, 1, 0, U32_MAX-1, U32_MAX, true, false, false},
78 {U32_MAX, U32_MAX, U32_MAX-1, 0, 1, true, false, true},
79
80 {U32_MAX, U32_MAX-1, U32_MAX-2, 1, 2, true, false, true},
81 {U32_MAX-1, U32_MAX, U32_MAX-2, U32_MAX, 2, true, true, true},
82
83 {1U << 15, 1U << 15, 1U << 16, 0, 1U << 30, false, false, false},
84 {1U << 16, 1U << 16, 1U << 17, 0, 0, false, false, true},
85 {1U << 16, 1U << 15, 3*(1U << 15), 1U << 15, 1U << 31, false, false, false},
86 {1U << 31, 1U << 31, 0, 0, 0, true, false, true},
87
88 {-2U, 1U, -1U, -3U, -2U, false, false, false},
89 {-4U, 5U, 1U, -9U, -20U, true, false, true},
90};
91
92DEFINE_TEST_ARRAY(u64) = {
93 {0, 0, 0, 0, 0, false, false, false},
94 {1, 1, 2, 0, 1, false, false, false},
95 {0, 1, 1, U64_MAX, 0, false, true, false},
96 {1, 0, 1, 1, 0, false, false, false},
97 {0, U64_MAX, U64_MAX, 1, 0, false, true, false},
98 {U64_MAX, 0, U64_MAX, U64_MAX, 0, false, false, false},
99 {1, U64_MAX, 0, 2, U64_MAX, true, true, false},
100 {U64_MAX, 1, 0, U64_MAX-1, U64_MAX, true, false, false},
101 {U64_MAX, U64_MAX, U64_MAX-1, 0, 1, true, false, true},
102
103 {U64_MAX, U64_MAX-1, U64_MAX-2, 1, 2, true, false, true},
104 {U64_MAX-1, U64_MAX, U64_MAX-2, U64_MAX, 2, true, true, true},
105
106 {1ULL << 31, 1ULL << 31, 1ULL << 32, 0, 1ULL << 62, false, false, false},
107 {1ULL << 32, 1ULL << 32, 1ULL << 33, 0, 0, false, false, true},
108 {1ULL << 32, 1ULL << 31, 3*(1ULL << 31), 1ULL << 31, 1ULL << 63, false, false, false},
109 {1ULL << 63, 1ULL << 63, 0, 0, 0, true, false, true},
110 {1000000000ULL /* 10^9 */, 10000000000ULL /* 10^10 */,
111 11000000000ULL, 18446744064709551616ULL, 10000000000000000000ULL,
112 false, true, false},
113 {-15ULL, 10ULL, -5ULL, -25ULL, -150ULL, false, false, true},
114};
115
116DEFINE_TEST_ARRAY(s8) = {
117 {0, 0, 0, 0, 0, false, false, false},
118
119 {0, S8_MAX, S8_MAX, -S8_MAX, 0, false, false, false},
120 {S8_MAX, 0, S8_MAX, S8_MAX, 0, false, false, false},
121 {0, S8_MIN, S8_MIN, S8_MIN, 0, false, true, false},
122 {S8_MIN, 0, S8_MIN, S8_MIN, 0, false, false, false},
123
124 {-1, S8_MIN, S8_MAX, S8_MAX, S8_MIN, true, false, true},
125 {S8_MIN, -1, S8_MAX, -S8_MAX, S8_MIN, true, false, true},
126 {-1, S8_MAX, S8_MAX-1, S8_MIN, -S8_MAX, false, false, false},
127 {S8_MAX, -1, S8_MAX-1, S8_MIN, -S8_MAX, false, true, false},
128 {-1, -S8_MAX, S8_MIN, S8_MAX-1, S8_MAX, false, false, false},
129 {-S8_MAX, -1, S8_MIN, S8_MIN+2, S8_MAX, false, false, false},
130
131 {1, S8_MIN, -S8_MAX, -S8_MAX, S8_MIN, false, true, false},
132 {S8_MIN, 1, -S8_MAX, S8_MAX, S8_MIN, false, true, false},
133 {1, S8_MAX, S8_MIN, S8_MIN+2, S8_MAX, true, false, false},
134 {S8_MAX, 1, S8_MIN, S8_MAX-1, S8_MAX, true, false, false},
135
136 {S8_MIN, S8_MIN, 0, 0, 0, true, false, true},
137 {S8_MAX, S8_MAX, -2, 0, 1, true, false, true},
138
139 {-4, -32, -36, 28, -128, false, false, true},
140 {-4, 32, 28, -36, -128, false, false, false},
141};
142
143DEFINE_TEST_ARRAY(s16) = {
144 {0, 0, 0, 0, 0, false, false, false},
145
146 {0, S16_MAX, S16_MAX, -S16_MAX, 0, false, false, false},
147 {S16_MAX, 0, S16_MAX, S16_MAX, 0, false, false, false},
148 {0, S16_MIN, S16_MIN, S16_MIN, 0, false, true, false},
149 {S16_MIN, 0, S16_MIN, S16_MIN, 0, false, false, false},
150
151 {-1, S16_MIN, S16_MAX, S16_MAX, S16_MIN, true, false, true},
152 {S16_MIN, -1, S16_MAX, -S16_MAX, S16_MIN, true, false, true},
153 {-1, S16_MAX, S16_MAX-1, S16_MIN, -S16_MAX, false, false, false},
154 {S16_MAX, -1, S16_MAX-1, S16_MIN, -S16_MAX, false, true, false},
155 {-1, -S16_MAX, S16_MIN, S16_MAX-1, S16_MAX, false, false, false},
156 {-S16_MAX, -1, S16_MIN, S16_MIN+2, S16_MAX, false, false, false},
157
158 {1, S16_MIN, -S16_MAX, -S16_MAX, S16_MIN, false, true, false},
159 {S16_MIN, 1, -S16_MAX, S16_MAX, S16_MIN, false, true, false},
160 {1, S16_MAX, S16_MIN, S16_MIN+2, S16_MAX, true, false, false},
161 {S16_MAX, 1, S16_MIN, S16_MAX-1, S16_MAX, true, false, false},
162
163 {S16_MIN, S16_MIN, 0, 0, 0, true, false, true},
164 {S16_MAX, S16_MAX, -2, 0, 1, true, false, true},
165};
166DEFINE_TEST_ARRAY(s32) = {
167 {0, 0, 0, 0, 0, false, false, false},
168
169 {0, S32_MAX, S32_MAX, -S32_MAX, 0, false, false, false},
170 {S32_MAX, 0, S32_MAX, S32_MAX, 0, false, false, false},
171 {0, S32_MIN, S32_MIN, S32_MIN, 0, false, true, false},
172 {S32_MIN, 0, S32_MIN, S32_MIN, 0, false, false, false},
173
174 {-1, S32_MIN, S32_MAX, S32_MAX, S32_MIN, true, false, true},
175 {S32_MIN, -1, S32_MAX, -S32_MAX, S32_MIN, true, false, true},
176 {-1, S32_MAX, S32_MAX-1, S32_MIN, -S32_MAX, false, false, false},
177 {S32_MAX, -1, S32_MAX-1, S32_MIN, -S32_MAX, false, true, false},
178 {-1, -S32_MAX, S32_MIN, S32_MAX-1, S32_MAX, false, false, false},
179 {-S32_MAX, -1, S32_MIN, S32_MIN+2, S32_MAX, false, false, false},
180
181 {1, S32_MIN, -S32_MAX, -S32_MAX, S32_MIN, false, true, false},
182 {S32_MIN, 1, -S32_MAX, S32_MAX, S32_MIN, false, true, false},
183 {1, S32_MAX, S32_MIN, S32_MIN+2, S32_MAX, true, false, false},
184 {S32_MAX, 1, S32_MIN, S32_MAX-1, S32_MAX, true, false, false},
185
186 {S32_MIN, S32_MIN, 0, 0, 0, true, false, true},
187 {S32_MAX, S32_MAX, -2, 0, 1, true, false, true},
188};
189DEFINE_TEST_ARRAY(s64) = {
190 {0, 0, 0, 0, 0, false, false, false},
191
192 {0, S64_MAX, S64_MAX, -S64_MAX, 0, false, false, false},
193 {S64_MAX, 0, S64_MAX, S64_MAX, 0, false, false, false},
194 {0, S64_MIN, S64_MIN, S64_MIN, 0, false, true, false},
195 {S64_MIN, 0, S64_MIN, S64_MIN, 0, false, false, false},
196
197 {-1, S64_MIN, S64_MAX, S64_MAX, S64_MIN, true, false, true},
198 {S64_MIN, -1, S64_MAX, -S64_MAX, S64_MIN, true, false, true},
199 {-1, S64_MAX, S64_MAX-1, S64_MIN, -S64_MAX, false, false, false},
200 {S64_MAX, -1, S64_MAX-1, S64_MIN, -S64_MAX, false, true, false},
201 {-1, -S64_MAX, S64_MIN, S64_MAX-1, S64_MAX, false, false, false},
202 {-S64_MAX, -1, S64_MIN, S64_MIN+2, S64_MAX, false, false, false},
203
204 {1, S64_MIN, -S64_MAX, -S64_MAX, S64_MIN, false, true, false},
205 {S64_MIN, 1, -S64_MAX, S64_MAX, S64_MIN, false, true, false},
206 {1, S64_MAX, S64_MIN, S64_MIN+2, S64_MAX, true, false, false},
207 {S64_MAX, 1, S64_MIN, S64_MAX-1, S64_MAX, true, false, false},
208
209 {S64_MIN, S64_MIN, 0, 0, 0, true, false, true},
210 {S64_MAX, S64_MAX, -2, 0, 1, true, false, true},
211
212 {-1, -1, -2, 0, 1, false, false, false},
213 {-1, -128, -129, 127, 128, false, false, false},
214 {-128, -1, -129, -127, 128, false, false, false},
215 {0, -S64_MAX, -S64_MAX, S64_MAX, 0, false, false, false},
216};
217
218#define check_one_op(t, fmt, op, sym, a, b, r, of) do { \
219 t _r; \
220 bool _of; \
221 \
222 _of = check_ ## op ## _overflow(a, b, &_r); \
223 if (_of != of) { \
224 pr_warn("expected "fmt" "sym" "fmt \
225 " to%s overflow (type %s)\n", \
226 a, b, of ? "" : " not", #t); \
227 err = 1; \
228 } \
229 if (_r != r) { \
230 pr_warn("expected "fmt" "sym" "fmt" == " \
231 fmt", got "fmt" (type %s)\n", \
232 a, b, r, _r, #t); \
233 err = 1; \
234 } \
235} while (0)
236
237#define DEFINE_TEST_FUNC(t, fmt) \
238static int __init do_test_ ## t(const struct test_ ## t *p) \
239{ \
240 int err = 0; \
241 \
242 check_one_op(t, fmt, add, "+", p->a, p->b, p->sum, p->s_of); \
243 check_one_op(t, fmt, add, "+", p->b, p->a, p->sum, p->s_of); \
244 check_one_op(t, fmt, sub, "-", p->a, p->b, p->diff, p->d_of); \
245 check_one_op(t, fmt, mul, "*", p->a, p->b, p->prod, p->p_of); \
246 check_one_op(t, fmt, mul, "*", p->b, p->a, p->prod, p->p_of); \
247 \
248 return err; \
249} \
250 \
251static int __init test_ ## t ## _overflow(void) { \
252 int err = 0; \
253 unsigned i; \
254 \
255 pr_info("%-3s: %zu tests\n", #t, ARRAY_SIZE(t ## _tests)); \
256 for (i = 0; i < ARRAY_SIZE(t ## _tests); ++i) \
257 err |= do_test_ ## t(&t ## _tests[i]); \
258 return err; \
259}
260
261DEFINE_TEST_FUNC(u8, "%d");
262DEFINE_TEST_FUNC(s8, "%d");
263DEFINE_TEST_FUNC(u16, "%d");
264DEFINE_TEST_FUNC(s16, "%d");
265DEFINE_TEST_FUNC(u32, "%u");
266DEFINE_TEST_FUNC(s32, "%d");
267#if BITS_PER_LONG == 64
268DEFINE_TEST_FUNC(u64, "%llu");
269DEFINE_TEST_FUNC(s64, "%lld");
270#endif
271
272static int __init test_overflow_calculation(void)
273{
274 int err = 0;
275
276 err |= test_u8_overflow();
277 err |= test_s8_overflow();
278 err |= test_u16_overflow();
279 err |= test_s16_overflow();
280 err |= test_u32_overflow();
281 err |= test_s32_overflow();
282#if BITS_PER_LONG == 64
283 err |= test_u64_overflow();
284 err |= test_s64_overflow();
285#endif
286
287 return err;
288}
289
290/*
291 * Deal with the various forms of allocator arguments. See comments above
292 * the DEFINE_TEST_ALLOC() instances for mapping of the "bits".
293 */
294#define alloc010(alloc, arg, sz) alloc(sz, GFP_KERNEL)
295#define alloc011(alloc, arg, sz) alloc(sz, GFP_KERNEL, NUMA_NO_NODE)
296#define alloc000(alloc, arg, sz) alloc(sz)
297#define alloc001(alloc, arg, sz) alloc(sz, NUMA_NO_NODE)
298#define alloc110(alloc, arg, sz) alloc(arg, sz, GFP_KERNEL)
299#define free0(free, arg, ptr) free(ptr)
300#define free1(free, arg, ptr) free(arg, ptr)
301
302/* Wrap around to 8K */
303#define TEST_SIZE (9 << PAGE_SHIFT)
304
305#define DEFINE_TEST_ALLOC(func, free_func, want_arg, want_gfp, want_node)\
306static int __init test_ ## func (void *arg) \
307{ \
308 volatile size_t a = TEST_SIZE; \
309 volatile size_t b = (SIZE_MAX / TEST_SIZE) + 1; \
310 void *ptr; \
311 \
312 /* Tiny allocation test. */ \
313 ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, 1);\
314 if (!ptr) { \
315 pr_warn(#func " failed regular allocation?!\n"); \
316 return 1; \
317 } \
318 free ## want_arg (free_func, arg, ptr); \
319 \
320 /* Wrapped allocation test. */ \
321 ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, \
322 a * b); \
323 if (!ptr) { \
324 pr_warn(#func " unexpectedly failed bad wrapping?!\n"); \
325 return 1; \
326 } \
327 free ## want_arg (free_func, arg, ptr); \
328 \
329 /* Saturated allocation test. */ \
330 ptr = alloc ## want_arg ## want_gfp ## want_node (func, arg, \
331 array_size(a, b)); \
332 if (ptr) { \
333 pr_warn(#func " missed saturation!\n"); \
334 free ## want_arg (free_func, arg, ptr); \
335 return 1; \
336 } \
337 pr_info(#func " detected saturation\n"); \
338 return 0; \
339}
340
341/*
342 * Allocator uses a trailing node argument --------+ (e.g. kmalloc_node())
343 * Allocator uses the gfp_t argument -----------+ | (e.g. kmalloc())
344 * Allocator uses a special leading argument + | | (e.g. devm_kmalloc())
345 * | | |
346 */
347DEFINE_TEST_ALLOC(kmalloc, kfree, 0, 1, 0);
348DEFINE_TEST_ALLOC(kmalloc_node, kfree, 0, 1, 1);
349DEFINE_TEST_ALLOC(kzalloc, kfree, 0, 1, 0);
350DEFINE_TEST_ALLOC(kzalloc_node, kfree, 0, 1, 1);
351DEFINE_TEST_ALLOC(vmalloc, vfree, 0, 0, 0);
352DEFINE_TEST_ALLOC(vmalloc_node, vfree, 0, 0, 1);
353DEFINE_TEST_ALLOC(vzalloc, vfree, 0, 0, 0);
354DEFINE_TEST_ALLOC(vzalloc_node, vfree, 0, 0, 1);
355DEFINE_TEST_ALLOC(kvmalloc, kvfree, 0, 1, 0);
356DEFINE_TEST_ALLOC(kvmalloc_node, kvfree, 0, 1, 1);
357DEFINE_TEST_ALLOC(kvzalloc, kvfree, 0, 1, 0);
358DEFINE_TEST_ALLOC(kvzalloc_node, kvfree, 0, 1, 1);
359DEFINE_TEST_ALLOC(devm_kmalloc, devm_kfree, 1, 1, 0);
360DEFINE_TEST_ALLOC(devm_kzalloc, devm_kfree, 1, 1, 0);
361
362static int __init test_overflow_allocation(void)
363{
364 const char device_name[] = "overflow-test";
365 struct device *dev;
366 int err = 0;
367
368 /* Create dummy device for devm_kmalloc()-family tests. */
369 dev = root_device_register(device_name);
370 if (!dev) {
371 pr_warn("Cannot register test device\n");
372 return 1;
373 }
374
375 err |= test_kmalloc(NULL);
376 err |= test_kmalloc_node(NULL);
377 err |= test_kzalloc(NULL);
378 err |= test_kzalloc_node(NULL);
379 err |= test_kvmalloc(NULL);
380 err |= test_kvmalloc_node(NULL);
381 err |= test_kvzalloc(NULL);
382 err |= test_kvzalloc_node(NULL);
383 err |= test_vmalloc(NULL);
384 err |= test_vmalloc_node(NULL);
385 err |= test_vzalloc(NULL);
386 err |= test_vzalloc_node(NULL);
387 err |= test_devm_kmalloc(dev);
388 err |= test_devm_kzalloc(dev);
389
390 device_unregister(dev);
391
392 return err;
393}
394
395static int __init test_module_init(void)
396{
397 int err = 0;
398
399 err |= test_overflow_calculation();
400 err |= test_overflow_allocation();
401
402 if (err) {
403 pr_warn("FAIL!\n");
404 err = -EINVAL;
405 } else {
406 pr_info("all tests passed\n");
407 }
408
409 return err;
410}
411
412static void __exit test_module_exit(void)
413{ }
414
415module_init(test_module_init);
416module_exit(test_module_exit);
417MODULE_LICENSE("Dual MIT/GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-11-04 08:19:14 -0500