1 /*
2 * Test cases for printf facility.
3 */
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/printk.h>
11 #include <linux/random.h>
12 #include <linux/slab.h>
13 #include <linux/string.h>
14
15 #include <linux/socket.h>
16 #include <linux/in.h>
17
18 #define BUF_SIZE 256
19 #define FILL_CHAR '$'
20
21 #define PTR1 ((void*)0x01234567)
22 #define PTR2 ((void*)(long)(int)0xfedcba98)
23
24 #if BITS_PER_LONG == 64
25 #define PTR1_ZEROES "000000000"
26 #define PTR1_SPACES " "
27 #define PTR1_STR "1234567"
28 #define PTR2_STR "fffffffffedcba98"
29 #define PTR_WIDTH 16
30 #else
31 #define PTR1_ZEROES "0"
32 #define PTR1_SPACES " "
33 #define PTR1_STR "1234567"
34 #define PTR2_STR "fedcba98"
35 #define PTR_WIDTH 8
36 #endif
37 #define PTR_WIDTH_STR stringify(PTR_WIDTH)
38
39 static unsigned total_tests __initdata;
40 static unsigned failed_tests __initdata;
41 static char *test_buffer __initdata;
42
43 static int __printf(4, 0) __init
do_test(int bufsize,const char * expect,int elen,const char * fmt,va_list ap)44 do_test(int bufsize, const char *expect, int elen,
45 const char *fmt, va_list ap)
46 {
47 va_list aq;
48 int ret, written;
49
50 total_tests++;
51
52 memset(test_buffer, FILL_CHAR, BUF_SIZE);
53 va_copy(aq, ap);
54 ret = vsnprintf(test_buffer, bufsize, fmt, aq);
55 va_end(aq);
56
57 if (ret != elen) {
58 pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n",
59 bufsize, fmt, ret, elen);
60 return 1;
61 }
62
63 if (!bufsize) {
64 if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE)) {
65 pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n",
66 fmt);
67 return 1;
68 }
69 return 0;
70 }
71
72 written = min(bufsize-1, elen);
73 if (test_buffer[written]) {
74 pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n",
75 bufsize, fmt);
76 return 1;
77 }
78
79 if (memcmp(test_buffer, expect, written)) {
80 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n",
81 bufsize, fmt, test_buffer, written, expect);
82 return 1;
83 }
84 return 0;
85 }
86
87 static void __printf(3, 4) __init
__test(const char * expect,int elen,const char * fmt,...)88 __test(const char *expect, int elen, const char *fmt, ...)
89 {
90 va_list ap;
91 int rand;
92 char *p;
93
94 BUG_ON(elen >= BUF_SIZE);
95
96 va_start(ap, fmt);
97
98 /*
99 * Every fmt+args is subjected to four tests: Three where we
100 * tell vsnprintf varying buffer sizes (plenty, not quite
101 * enough and 0), and then we also test that kvasprintf would
102 * be able to print it as expected.
103 */
104 failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap);
105 rand = 1 + prandom_u32_max(elen+1);
106 /* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */
107 failed_tests += do_test(rand, expect, elen, fmt, ap);
108 failed_tests += do_test(0, expect, elen, fmt, ap);
109
110 p = kvasprintf(GFP_KERNEL, fmt, ap);
111 if (p) {
112 if (memcmp(p, expect, elen+1)) {
113 pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n",
114 fmt, p, expect);
115 failed_tests++;
116 }
117 kfree(p);
118 }
119 va_end(ap);
120 }
121
122 #define test(expect, fmt, ...) \
123 __test(expect, strlen(expect), fmt, ##__VA_ARGS__)
124
125 static void __init
test_basic(void)126 test_basic(void)
127 {
128 /* Work around annoying "warning: zero-length gnu_printf format string". */
129 char nul = '\0';
130
131 test("", &nul);
132 test("100%", "100%%");
133 test("xxx%yyy", "xxx%cyyy", '%');
134 __test("xxx\0yyy", 7, "xxx%cyyy", '\0');
135 }
136
137 static void __init
test_number(void)138 test_number(void)
139 {
140 test("0x1234abcd ", "%#-12x", 0x1234abcd);
141 test(" 0x1234abcd", "%#12x", 0x1234abcd);
142 test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234);
143 }
144
145 static void __init
test_string(void)146 test_string(void)
147 {
148 test("", "%s%.0s", "", "123");
149 test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456");
150 test("1 | 2|3 | 4|5 ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5");
151 /*
152 * POSIX and C99 say that a missing precision should be
153 * treated as a precision of 0. However, the kernel's printf
154 * implementation treats this case as if the . wasn't
155 * present. Let's add a test case documenting the current
156 * behaviour; should anyone ever feel the need to follow the
157 * standards more closely, this can be revisited.
158 */
159 test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c");
160 test("a | | ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c");
161 }
162
163 static void __init
plain(void)164 plain(void)
165 {
166 test(PTR1_ZEROES PTR1_STR " " PTR2_STR, "%p %p", PTR1, PTR2);
167 /*
168 * The field width is overloaded for some %p extensions to
169 * pass another piece of information. For plain pointers, the
170 * behaviour is slightly odd: One cannot pass either the 0
171 * flag nor a precision to %p without gcc complaining, and if
172 * one explicitly gives a field width, the number is no longer
173 * zero-padded.
174 */
175 test("|" PTR1_STR PTR1_SPACES " | " PTR1_SPACES PTR1_STR "|",
176 "|%-*p|%*p|", PTR_WIDTH+2, PTR1, PTR_WIDTH+2, PTR1);
177 test("|" PTR2_STR " | " PTR2_STR "|",
178 "|%-*p|%*p|", PTR_WIDTH+2, PTR2, PTR_WIDTH+2, PTR2);
179
180 /*
181 * Unrecognized %p extensions are treated as plain %p, but the
182 * alphanumeric suffix is ignored (that is, does not occur in
183 * the output.)
184 */
185 test("|"PTR1_ZEROES PTR1_STR"|", "|%p0y|", PTR1);
186 test("|"PTR2_STR"|", "|%p0y|", PTR2);
187 }
188
189 static void __init
symbol_ptr(void)190 symbol_ptr(void)
191 {
192 }
193
194 static void __init
kernel_ptr(void)195 kernel_ptr(void)
196 {
197 }
198
199 static void __init
struct_resource(void)200 struct_resource(void)
201 {
202 }
203
204 static void __init
addr(void)205 addr(void)
206 {
207 }
208
209 static void __init
escaped_str(void)210 escaped_str(void)
211 {
212 }
213
214 static void __init
hex_string(void)215 hex_string(void)
216 {
217 const char buf[3] = {0xc0, 0xff, 0xee};
218
219 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee",
220 "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf);
221 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee",
222 "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf);
223 }
224
225 static void __init
mac(void)226 mac(void)
227 {
228 const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05};
229
230 test("2d:48:d6:fc:7a:05", "%pM", addr);
231 test("05:7a:fc:d6:48:2d", "%pMR", addr);
232 test("2d-48-d6-fc-7a-05", "%pMF", addr);
233 test("2d48d6fc7a05", "%pm", addr);
234 test("057afcd6482d", "%pmR", addr);
235 }
236
237 static void __init
ip4(void)238 ip4(void)
239 {
240 struct sockaddr_in sa;
241
242 sa.sin_family = AF_INET;
243 sa.sin_port = cpu_to_be16(12345);
244 sa.sin_addr.s_addr = cpu_to_be32(0x7f000001);
245
246 test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr);
247 test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa);
248 sa.sin_addr.s_addr = cpu_to_be32(0x01020304);
249 test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa);
250 }
251
252 static void __init
ip6(void)253 ip6(void)
254 {
255 }
256
257 static void __init
ip(void)258 ip(void)
259 {
260 ip4();
261 ip6();
262 }
263
264 static void __init
uuid(void)265 uuid(void)
266 {
267 const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
268 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf};
269
270 test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid);
271 test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid);
272 test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid);
273 test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid);
274 }
275
276 static void __init
dentry(void)277 dentry(void)
278 {
279 }
280
281 static void __init
struct_va_format(void)282 struct_va_format(void)
283 {
284 }
285
286 static void __init
struct_clk(void)287 struct_clk(void)
288 {
289 }
290
291 static void __init
bitmap(void)292 bitmap(void)
293 {
294 DECLARE_BITMAP(bits, 20);
295 const int primes[] = {2,3,5,7,11,13,17,19};
296 int i;
297
298 bitmap_zero(bits, 20);
299 test("00000|00000", "%20pb|%*pb", bits, 20, bits);
300 test("|", "%20pbl|%*pbl", bits, 20, bits);
301
302 for (i = 0; i < ARRAY_SIZE(primes); ++i)
303 set_bit(primes[i], bits);
304 test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits);
305 test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits);
306
307 bitmap_fill(bits, 20);
308 test("fffff|fffff", "%20pb|%*pb", bits, 20, bits);
309 test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits);
310 }
311
312 static void __init
netdev_features(void)313 netdev_features(void)
314 {
315 }
316
317 static void __init
test_pointer(void)318 test_pointer(void)
319 {
320 plain();
321 symbol_ptr();
322 kernel_ptr();
323 struct_resource();
324 addr();
325 escaped_str();
326 hex_string();
327 mac();
328 ip();
329 uuid();
330 dentry();
331 struct_va_format();
332 struct_clk();
333 bitmap();
334 netdev_features();
335 }
336
337 static int __init
test_printf_init(void)338 test_printf_init(void)
339 {
340 test_buffer = kmalloc(BUF_SIZE, GFP_KERNEL);
341 if (!test_buffer)
342 return -ENOMEM;
343
344 test_basic();
345 test_number();
346 test_string();
347 test_pointer();
348
349 kfree(test_buffer);
350
351 if (failed_tests == 0)
352 pr_info("all %u tests passed\n", total_tests);
353 else
354 pr_warn("failed %u out of %u tests\n", failed_tests, total_tests);
355
356 return failed_tests ? -EINVAL : 0;
357 }
358
359 module_init(test_printf_init);
360
361 MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>");
362 MODULE_LICENSE("GPL");
363