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/bitmap.h> 16 #include <linux/dcache.h> 17 #include <linux/socket.h> 18 #include <linux/in.h> 19 20 #define BUF_SIZE 256 21 #define PAD_SIZE 16 22 #define FILL_CHAR '$' 23 24 #define PTR1 ((void*)0x01234567) 25 #define PTR2 ((void*)(long)(int)0xfedcba98) 26 27 #if BITS_PER_LONG == 64 28 #define PTR1_ZEROES "000000000" 29 #define PTR1_SPACES " " 30 #define PTR1_STR "1234567" 31 #define PTR2_STR "fffffffffedcba98" 32 #define PTR_WIDTH 16 33 #else 34 #define PTR1_ZEROES "0" 35 #define PTR1_SPACES " " 36 #define PTR1_STR "1234567" 37 #define PTR2_STR "fedcba98" 38 #define PTR_WIDTH 8 39 #endif 40 #define PTR_WIDTH_STR stringify(PTR_WIDTH) 41 42 static unsigned total_tests __initdata; 43 static unsigned failed_tests __initdata; 44 static char *test_buffer __initdata; 45 static char *alloced_buffer __initdata; 46 47 static int __printf(4, 0) __init 48 do_test(int bufsize, const char *expect, int elen, 49 const char *fmt, va_list ap) 50 { 51 va_list aq; 52 int ret, written; 53 54 total_tests++; 55 56 memset(alloced_buffer, FILL_CHAR, BUF_SIZE + 2*PAD_SIZE); 57 va_copy(aq, ap); 58 ret = vsnprintf(test_buffer, bufsize, fmt, aq); 59 va_end(aq); 60 61 if (ret != elen) { 62 pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n", 63 bufsize, fmt, ret, elen); 64 return 1; 65 } 66 67 if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) { 68 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt); 69 return 1; 70 } 71 72 if (!bufsize) { 73 if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) { 74 pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n", 75 fmt); 76 return 1; 77 } 78 return 0; 79 } 80 81 written = min(bufsize-1, elen); 82 if (test_buffer[written]) { 83 pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n", 84 bufsize, fmt); 85 return 1; 86 } 87 88 if (memchr_inv(test_buffer + written + 1, FILL_CHAR, BUF_SIZE + PAD_SIZE - (written + 1))) { 89 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n", 90 bufsize, fmt); 91 return 1; 92 } 93 94 if (memcmp(test_buffer, expect, written)) { 95 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n", 96 bufsize, fmt, test_buffer, written, expect); 97 return 1; 98 } 99 return 0; 100 } 101 102 static void __printf(3, 4) __init 103 __test(const char *expect, int elen, const char *fmt, ...) 104 { 105 va_list ap; 106 int rand; 107 char *p; 108 109 if (elen >= BUF_SIZE) { 110 pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n", 111 elen, fmt); 112 failed_tests++; 113 return; 114 } 115 116 va_start(ap, fmt); 117 118 /* 119 * Every fmt+args is subjected to four tests: Three where we 120 * tell vsnprintf varying buffer sizes (plenty, not quite 121 * enough and 0), and then we also test that kvasprintf would 122 * be able to print it as expected. 123 */ 124 failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap); 125 rand = 1 + prandom_u32_max(elen+1); 126 /* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */ 127 failed_tests += do_test(rand, expect, elen, fmt, ap); 128 failed_tests += do_test(0, expect, elen, fmt, ap); 129 130 p = kvasprintf(GFP_KERNEL, fmt, ap); 131 if (p) { 132 total_tests++; 133 if (memcmp(p, expect, elen+1)) { 134 pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n", 135 fmt, p, expect); 136 failed_tests++; 137 } 138 kfree(p); 139 } 140 va_end(ap); 141 } 142 143 #define test(expect, fmt, ...) \ 144 __test(expect, strlen(expect), fmt, ##__VA_ARGS__) 145 146 static void __init 147 test_basic(void) 148 { 149 /* Work around annoying "warning: zero-length gnu_printf format string". */ 150 char nul = '\0'; 151 152 test("", &nul); 153 test("100%", "100%%"); 154 test("xxx%yyy", "xxx%cyyy", '%'); 155 __test("xxx\0yyy", 7, "xxx%cyyy", '\0'); 156 } 157 158 static void __init 159 test_number(void) 160 { 161 test("0x1234abcd ", "%#-12x", 0x1234abcd); 162 test(" 0x1234abcd", "%#12x", 0x1234abcd); 163 test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234); 164 test("0|1|1|128|255", "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1); 165 test("0|1|1|-128|-1", "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1); 166 test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627); 167 /* 168 * POSIX/C99: »The result of converting zero with an explicit 169 * precision of zero shall be no characters.« Hence the output 170 * from the below test should really be "00|0||| ". However, 171 * the kernel's printf also produces a single 0 in that 172 * case. This test case simply documents the current 173 * behaviour. 174 */ 175 test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0); 176 #ifndef __CHAR_UNSIGNED__ 177 { 178 /* 179 * Passing a 'char' to a %02x specifier doesn't do 180 * what was presumably the intention when char is 181 * signed and the value is negative. One must either & 182 * with 0xff or cast to u8. 183 */ 184 char val = -16; 185 test("0xfffffff0|0xf0|0xf0", "%#02x|%#02x|%#02x", val, val & 0xff, (u8)val); 186 } 187 #endif 188 } 189 190 static void __init 191 test_string(void) 192 { 193 test("", "%s%.0s", "", "123"); 194 test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456"); 195 test("1 | 2|3 | 4|5 ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5"); 196 test("1234 ", "%-10.4s", "123456"); 197 test(" 1234", "%10.4s", "123456"); 198 /* 199 * POSIX and C99 say that a negative precision (which is only 200 * possible to pass via a * argument) should be treated as if 201 * the precision wasn't present, and that if the precision is 202 * omitted (as in %.s), the precision should be taken to be 203 * 0. However, the kernel's printf behave exactly opposite, 204 * treating a negative precision as 0 and treating an omitted 205 * precision specifier as if no precision was given. 206 * 207 * These test cases document the current behaviour; should 208 * anyone ever feel the need to follow the standards more 209 * closely, this can be revisited. 210 */ 211 test(" ", "%4.*s", -5, "123456"); 212 test("123456", "%.s", "123456"); 213 test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c"); 214 test("a | | ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c"); 215 } 216 217 static void __init 218 plain(void) 219 { 220 test(PTR1_ZEROES PTR1_STR " " PTR2_STR, "%p %p", PTR1, PTR2); 221 /* 222 * The field width is overloaded for some %p extensions to 223 * pass another piece of information. For plain pointers, the 224 * behaviour is slightly odd: One cannot pass either the 0 225 * flag nor a precision to %p without gcc complaining, and if 226 * one explicitly gives a field width, the number is no longer 227 * zero-padded. 228 */ 229 test("|" PTR1_STR PTR1_SPACES " | " PTR1_SPACES PTR1_STR "|", 230 "|%-*p|%*p|", PTR_WIDTH+2, PTR1, PTR_WIDTH+2, PTR1); 231 test("|" PTR2_STR " | " PTR2_STR "|", 232 "|%-*p|%*p|", PTR_WIDTH+2, PTR2, PTR_WIDTH+2, PTR2); 233 234 /* 235 * Unrecognized %p extensions are treated as plain %p, but the 236 * alphanumeric suffix is ignored (that is, does not occur in 237 * the output.) 238 */ 239 test("|"PTR1_ZEROES PTR1_STR"|", "|%p0y|", PTR1); 240 test("|"PTR2_STR"|", "|%p0y|", PTR2); 241 } 242 243 static void __init 244 symbol_ptr(void) 245 { 246 } 247 248 static void __init 249 kernel_ptr(void) 250 { 251 } 252 253 static void __init 254 struct_resource(void) 255 { 256 } 257 258 static void __init 259 addr(void) 260 { 261 } 262 263 static void __init 264 escaped_str(void) 265 { 266 } 267 268 static void __init 269 hex_string(void) 270 { 271 const char buf[3] = {0xc0, 0xff, 0xee}; 272 273 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 274 "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf); 275 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 276 "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf); 277 } 278 279 static void __init 280 mac(void) 281 { 282 const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05}; 283 284 test("2d:48:d6:fc:7a:05", "%pM", addr); 285 test("05:7a:fc:d6:48:2d", "%pMR", addr); 286 test("2d-48-d6-fc-7a-05", "%pMF", addr); 287 test("2d48d6fc7a05", "%pm", addr); 288 test("057afcd6482d", "%pmR", addr); 289 } 290 291 static void __init 292 ip4(void) 293 { 294 struct sockaddr_in sa; 295 296 sa.sin_family = AF_INET; 297 sa.sin_port = cpu_to_be16(12345); 298 sa.sin_addr.s_addr = cpu_to_be32(0x7f000001); 299 300 test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr); 301 test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa); 302 sa.sin_addr.s_addr = cpu_to_be32(0x01020304); 303 test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa); 304 } 305 306 static void __init 307 ip6(void) 308 { 309 } 310 311 static void __init 312 ip(void) 313 { 314 ip4(); 315 ip6(); 316 } 317 318 static void __init 319 uuid(void) 320 { 321 const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 322 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf}; 323 324 test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid); 325 test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid); 326 test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid); 327 test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid); 328 } 329 330 static struct dentry test_dentry[4] __initdata = { 331 { .d_parent = &test_dentry[0], 332 .d_name = QSTR_INIT(test_dentry[0].d_iname, 3), 333 .d_iname = "foo" }, 334 { .d_parent = &test_dentry[0], 335 .d_name = QSTR_INIT(test_dentry[1].d_iname, 5), 336 .d_iname = "bravo" }, 337 { .d_parent = &test_dentry[1], 338 .d_name = QSTR_INIT(test_dentry[2].d_iname, 4), 339 .d_iname = "alfa" }, 340 { .d_parent = &test_dentry[2], 341 .d_name = QSTR_INIT(test_dentry[3].d_iname, 5), 342 .d_iname = "romeo" }, 343 }; 344 345 static void __init 346 dentry(void) 347 { 348 test("foo", "%pd", &test_dentry[0]); 349 test("foo", "%pd2", &test_dentry[0]); 350 351 test("romeo", "%pd", &test_dentry[3]); 352 test("alfa/romeo", "%pd2", &test_dentry[3]); 353 test("bravo/alfa/romeo", "%pd3", &test_dentry[3]); 354 test("/bravo/alfa/romeo", "%pd4", &test_dentry[3]); 355 test("/bravo/alfa", "%pd4", &test_dentry[2]); 356 357 test("bravo/alfa |bravo/alfa ", "%-12pd2|%*pd2", &test_dentry[2], -12, &test_dentry[2]); 358 test(" bravo/alfa| bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]); 359 } 360 361 static void __init 362 struct_va_format(void) 363 { 364 } 365 366 static void __init 367 struct_clk(void) 368 { 369 } 370 371 static void __init 372 large_bitmap(void) 373 { 374 const int nbits = 1 << 16; 375 unsigned long *bits = kcalloc(BITS_TO_LONGS(nbits), sizeof(long), GFP_KERNEL); 376 if (!bits) 377 return; 378 379 bitmap_set(bits, 1, 20); 380 bitmap_set(bits, 60000, 15); 381 test("1-20,60000-60014", "%*pbl", nbits, bits); 382 kfree(bits); 383 } 384 385 static void __init 386 bitmap(void) 387 { 388 DECLARE_BITMAP(bits, 20); 389 const int primes[] = {2,3,5,7,11,13,17,19}; 390 int i; 391 392 bitmap_zero(bits, 20); 393 test("00000|00000", "%20pb|%*pb", bits, 20, bits); 394 test("|", "%20pbl|%*pbl", bits, 20, bits); 395 396 for (i = 0; i < ARRAY_SIZE(primes); ++i) 397 set_bit(primes[i], bits); 398 test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits); 399 test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits); 400 401 bitmap_fill(bits, 20); 402 test("fffff|fffff", "%20pb|%*pb", bits, 20, bits); 403 test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits); 404 405 large_bitmap(); 406 } 407 408 static void __init 409 netdev_features(void) 410 { 411 } 412 413 static void __init 414 test_pointer(void) 415 { 416 plain(); 417 symbol_ptr(); 418 kernel_ptr(); 419 struct_resource(); 420 addr(); 421 escaped_str(); 422 hex_string(); 423 mac(); 424 ip(); 425 uuid(); 426 dentry(); 427 struct_va_format(); 428 struct_clk(); 429 bitmap(); 430 netdev_features(); 431 } 432 433 static int __init 434 test_printf_init(void) 435 { 436 alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL); 437 if (!alloced_buffer) 438 return -ENOMEM; 439 test_buffer = alloced_buffer + PAD_SIZE; 440 441 test_basic(); 442 test_number(); 443 test_string(); 444 test_pointer(); 445 446 kfree(alloced_buffer); 447 448 if (failed_tests == 0) 449 pr_info("all %u tests passed\n", total_tests); 450 else 451 pr_warn("failed %u out of %u tests\n", failed_tests, total_tests); 452 453 return failed_tests ? -EINVAL : 0; 454 } 455 456 module_init(test_printf_init); 457 458 MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>"); 459 MODULE_LICENSE("GPL"); 460