1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/module.h>
3 #include <linux/printk.h>
4 #include <linux/slab.h>
5 #include <linux/string.h>
6
memset16_selftest(void)7 static __init int memset16_selftest(void)
8 {
9 unsigned i, j, k;
10 u16 v, *p;
11
12 p = kmalloc(256 * 2 * 2, GFP_KERNEL);
13 if (!p)
14 return -1;
15
16 for (i = 0; i < 256; i++) {
17 for (j = 0; j < 256; j++) {
18 memset(p, 0xa1, 256 * 2 * sizeof(v));
19 memset16(p + i, 0xb1b2, j);
20 for (k = 0; k < 512; k++) {
21 v = p[k];
22 if (k < i) {
23 if (v != 0xa1a1)
24 goto fail;
25 } else if (k < i + j) {
26 if (v != 0xb1b2)
27 goto fail;
28 } else {
29 if (v != 0xa1a1)
30 goto fail;
31 }
32 }
33 }
34 }
35
36 fail:
37 kfree(p);
38 if (i < 256)
39 return (i << 24) | (j << 16) | k | 0x8000;
40 return 0;
41 }
42
memset32_selftest(void)43 static __init int memset32_selftest(void)
44 {
45 unsigned i, j, k;
46 u32 v, *p;
47
48 p = kmalloc(256 * 2 * 4, GFP_KERNEL);
49 if (!p)
50 return -1;
51
52 for (i = 0; i < 256; i++) {
53 for (j = 0; j < 256; j++) {
54 memset(p, 0xa1, 256 * 2 * sizeof(v));
55 memset32(p + i, 0xb1b2b3b4, j);
56 for (k = 0; k < 512; k++) {
57 v = p[k];
58 if (k < i) {
59 if (v != 0xa1a1a1a1)
60 goto fail;
61 } else if (k < i + j) {
62 if (v != 0xb1b2b3b4)
63 goto fail;
64 } else {
65 if (v != 0xa1a1a1a1)
66 goto fail;
67 }
68 }
69 }
70 }
71
72 fail:
73 kfree(p);
74 if (i < 256)
75 return (i << 24) | (j << 16) | k | 0x8000;
76 return 0;
77 }
78
memset64_selftest(void)79 static __init int memset64_selftest(void)
80 {
81 unsigned i, j, k;
82 u64 v, *p;
83
84 p = kmalloc(256 * 2 * 8, GFP_KERNEL);
85 if (!p)
86 return -1;
87
88 for (i = 0; i < 256; i++) {
89 for (j = 0; j < 256; j++) {
90 memset(p, 0xa1, 256 * 2 * sizeof(v));
91 memset64(p + i, 0xb1b2b3b4b5b6b7b8ULL, j);
92 for (k = 0; k < 512; k++) {
93 v = p[k];
94 if (k < i) {
95 if (v != 0xa1a1a1a1a1a1a1a1ULL)
96 goto fail;
97 } else if (k < i + j) {
98 if (v != 0xb1b2b3b4b5b6b7b8ULL)
99 goto fail;
100 } else {
101 if (v != 0xa1a1a1a1a1a1a1a1ULL)
102 goto fail;
103 }
104 }
105 }
106 }
107
108 fail:
109 kfree(p);
110 if (i < 256)
111 return (i << 24) | (j << 16) | k | 0x8000;
112 return 0;
113 }
114
strchr_selftest(void)115 static __init int strchr_selftest(void)
116 {
117 const char *test_string = "abcdefghijkl";
118 const char *empty_string = "";
119 char *result;
120 int i;
121
122 for (i = 0; i < strlen(test_string) + 1; i++) {
123 result = strchr(test_string, test_string[i]);
124 if (result - test_string != i)
125 return i + 'a';
126 }
127
128 result = strchr(empty_string, '\0');
129 if (result != empty_string)
130 return 0x101;
131
132 result = strchr(empty_string, 'a');
133 if (result)
134 return 0x102;
135
136 result = strchr(test_string, 'z');
137 if (result)
138 return 0x103;
139
140 return 0;
141 }
142
strnchr_selftest(void)143 static __init int strnchr_selftest(void)
144 {
145 const char *test_string = "abcdefghijkl";
146 const char *empty_string = "";
147 char *result;
148 int i, j;
149
150 for (i = 0; i < strlen(test_string) + 1; i++) {
151 for (j = 0; j < strlen(test_string) + 2; j++) {
152 result = strnchr(test_string, j, test_string[i]);
153 if (j <= i) {
154 if (!result)
155 continue;
156 return ((i + 'a') << 8) | j;
157 }
158 if (result - test_string != i)
159 return ((i + 'a') << 8) | j;
160 }
161 }
162
163 result = strnchr(empty_string, 0, '\0');
164 if (result)
165 return 0x10001;
166
167 result = strnchr(empty_string, 1, '\0');
168 if (result != empty_string)
169 return 0x10002;
170
171 result = strnchr(empty_string, 1, 'a');
172 if (result)
173 return 0x10003;
174
175 result = strnchr(NULL, 0, '\0');
176 if (result)
177 return 0x10004;
178
179 return 0;
180 }
181
string_selftest_init(void)182 static __init int string_selftest_init(void)
183 {
184 int test, subtest;
185
186 test = 1;
187 subtest = memset16_selftest();
188 if (subtest)
189 goto fail;
190
191 test = 2;
192 subtest = memset32_selftest();
193 if (subtest)
194 goto fail;
195
196 test = 3;
197 subtest = memset64_selftest();
198 if (subtest)
199 goto fail;
200
201 test = 4;
202 subtest = strchr_selftest();
203 if (subtest)
204 goto fail;
205
206 test = 5;
207 subtest = strnchr_selftest();
208 if (subtest)
209 goto fail;
210
211 pr_info("String selftests succeeded\n");
212 return 0;
213 fail:
214 pr_crit("String selftest failure %d.%08x\n", test, subtest);
215 return 0;
216 }
217
218 module_init(string_selftest_init);
219 MODULE_LICENSE("GPL v2");
220
