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 #include <linux/gfp.h> 21 #include <linux/mm.h> 22 23 #define BUF_SIZE 256 24 #define PAD_SIZE 16 25 #define FILL_CHAR '$' 26 27 #define PTR1 ((void*)0x01234567) 28 #define PTR2 ((void*)(long)(int)0xfedcba98) 29 30 #if BITS_PER_LONG == 64 31 #define PTR1_ZEROES "000000000" 32 #define PTR1_SPACES " " 33 #define PTR1_STR "1234567" 34 #define PTR2_STR "fffffffffedcba98" 35 #define PTR_WIDTH 16 36 #else 37 #define PTR1_ZEROES "0" 38 #define PTR1_SPACES " " 39 #define PTR1_STR "1234567" 40 #define PTR2_STR "fedcba98" 41 #define PTR_WIDTH 8 42 #endif 43 #define PTR_WIDTH_STR stringify(PTR_WIDTH) 44 45 static unsigned total_tests __initdata; 46 static unsigned failed_tests __initdata; 47 static char *test_buffer __initdata; 48 static char *alloced_buffer __initdata; 49 50 static int __printf(4, 0) __init 51 do_test(int bufsize, const char *expect, int elen, 52 const char *fmt, va_list ap) 53 { 54 va_list aq; 55 int ret, written; 56 57 total_tests++; 58 59 memset(alloced_buffer, FILL_CHAR, BUF_SIZE + 2*PAD_SIZE); 60 va_copy(aq, ap); 61 ret = vsnprintf(test_buffer, bufsize, fmt, aq); 62 va_end(aq); 63 64 if (ret != elen) { 65 pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n", 66 bufsize, fmt, ret, elen); 67 return 1; 68 } 69 70 if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) { 71 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt); 72 return 1; 73 } 74 75 if (!bufsize) { 76 if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) { 77 pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n", 78 fmt); 79 return 1; 80 } 81 return 0; 82 } 83 84 written = min(bufsize-1, elen); 85 if (test_buffer[written]) { 86 pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n", 87 bufsize, fmt); 88 return 1; 89 } 90 91 if (memchr_inv(test_buffer + written + 1, FILL_CHAR, BUF_SIZE + PAD_SIZE - (written + 1))) { 92 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n", 93 bufsize, fmt); 94 return 1; 95 } 96 97 if (memcmp(test_buffer, expect, written)) { 98 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n", 99 bufsize, fmt, test_buffer, written, expect); 100 return 1; 101 } 102 return 0; 103 } 104 105 static void __printf(3, 4) __init 106 __test(const char *expect, int elen, const char *fmt, ...) 107 { 108 va_list ap; 109 int rand; 110 char *p; 111 112 if (elen >= BUF_SIZE) { 113 pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n", 114 elen, fmt); 115 failed_tests++; 116 return; 117 } 118 119 va_start(ap, fmt); 120 121 /* 122 * Every fmt+args is subjected to four tests: Three where we 123 * tell vsnprintf varying buffer sizes (plenty, not quite 124 * enough and 0), and then we also test that kvasprintf would 125 * be able to print it as expected. 126 */ 127 failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap); 128 rand = 1 + prandom_u32_max(elen+1); 129 /* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */ 130 failed_tests += do_test(rand, expect, elen, fmt, ap); 131 failed_tests += do_test(0, expect, elen, fmt, ap); 132 133 p = kvasprintf(GFP_KERNEL, fmt, ap); 134 if (p) { 135 total_tests++; 136 if (memcmp(p, expect, elen+1)) { 137 pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n", 138 fmt, p, expect); 139 failed_tests++; 140 } 141 kfree(p); 142 } 143 va_end(ap); 144 } 145 146 #define test(expect, fmt, ...) \ 147 __test(expect, strlen(expect), fmt, ##__VA_ARGS__) 148 149 static void __init 150 test_basic(void) 151 { 152 /* Work around annoying "warning: zero-length gnu_printf format string". */ 153 char nul = '\0'; 154 155 test("", &nul); 156 test("100%", "100%%"); 157 test("xxx%yyy", "xxx%cyyy", '%'); 158 __test("xxx\0yyy", 7, "xxx%cyyy", '\0'); 159 } 160 161 static void __init 162 test_number(void) 163 { 164 test("0x1234abcd ", "%#-12x", 0x1234abcd); 165 test(" 0x1234abcd", "%#12x", 0x1234abcd); 166 test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234); 167 test("0|1|1|128|255", "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1); 168 test("0|1|1|-128|-1", "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1); 169 test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627); 170 /* 171 * POSIX/C99: »The result of converting zero with an explicit 172 * precision of zero shall be no characters.« Hence the output 173 * from the below test should really be "00|0||| ". However, 174 * the kernel's printf also produces a single 0 in that 175 * case. This test case simply documents the current 176 * behaviour. 177 */ 178 test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0); 179 #ifndef __CHAR_UNSIGNED__ 180 { 181 /* 182 * Passing a 'char' to a %02x specifier doesn't do 183 * what was presumably the intention when char is 184 * signed and the value is negative. One must either & 185 * with 0xff or cast to u8. 186 */ 187 char val = -16; 188 test("0xfffffff0|0xf0|0xf0", "%#02x|%#02x|%#02x", val, val & 0xff, (u8)val); 189 } 190 #endif 191 } 192 193 static void __init 194 test_string(void) 195 { 196 test("", "%s%.0s", "", "123"); 197 test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456"); 198 test("1 | 2|3 | 4|5 ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5"); 199 test("1234 ", "%-10.4s", "123456"); 200 test(" 1234", "%10.4s", "123456"); 201 /* 202 * POSIX and C99 say that a negative precision (which is only 203 * possible to pass via a * argument) should be treated as if 204 * the precision wasn't present, and that if the precision is 205 * omitted (as in %.s), the precision should be taken to be 206 * 0. However, the kernel's printf behave exactly opposite, 207 * treating a negative precision as 0 and treating an omitted 208 * precision specifier as if no precision was given. 209 * 210 * These test cases document the current behaviour; should 211 * anyone ever feel the need to follow the standards more 212 * closely, this can be revisited. 213 */ 214 test(" ", "%4.*s", -5, "123456"); 215 test("123456", "%.s", "123456"); 216 test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c"); 217 test("a | | ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c"); 218 } 219 220 static void __init 221 plain(void) 222 { 223 test(PTR1_ZEROES PTR1_STR " " PTR2_STR, "%p %p", PTR1, PTR2); 224 /* 225 * The field width is overloaded for some %p extensions to 226 * pass another piece of information. For plain pointers, the 227 * behaviour is slightly odd: One cannot pass either the 0 228 * flag nor a precision to %p without gcc complaining, and if 229 * one explicitly gives a field width, the number is no longer 230 * zero-padded. 231 */ 232 test("|" PTR1_STR PTR1_SPACES " | " PTR1_SPACES PTR1_STR "|", 233 "|%-*p|%*p|", PTR_WIDTH+2, PTR1, PTR_WIDTH+2, PTR1); 234 test("|" PTR2_STR " | " PTR2_STR "|", 235 "|%-*p|%*p|", PTR_WIDTH+2, PTR2, PTR_WIDTH+2, PTR2); 236 237 /* 238 * Unrecognized %p extensions are treated as plain %p, but the 239 * alphanumeric suffix is ignored (that is, does not occur in 240 * the output.) 241 */ 242 test("|"PTR1_ZEROES PTR1_STR"|", "|%p0y|", PTR1); 243 test("|"PTR2_STR"|", "|%p0y|", PTR2); 244 } 245 246 static void __init 247 symbol_ptr(void) 248 { 249 } 250 251 static void __init 252 kernel_ptr(void) 253 { 254 } 255 256 static void __init 257 struct_resource(void) 258 { 259 } 260 261 static void __init 262 addr(void) 263 { 264 } 265 266 static void __init 267 escaped_str(void) 268 { 269 } 270 271 static void __init 272 hex_string(void) 273 { 274 const char buf[3] = {0xc0, 0xff, 0xee}; 275 276 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 277 "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf); 278 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 279 "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf); 280 } 281 282 static void __init 283 mac(void) 284 { 285 const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05}; 286 287 test("2d:48:d6:fc:7a:05", "%pM", addr); 288 test("05:7a:fc:d6:48:2d", "%pMR", addr); 289 test("2d-48-d6-fc-7a-05", "%pMF", addr); 290 test("2d48d6fc7a05", "%pm", addr); 291 test("057afcd6482d", "%pmR", addr); 292 } 293 294 static void __init 295 ip4(void) 296 { 297 struct sockaddr_in sa; 298 299 sa.sin_family = AF_INET; 300 sa.sin_port = cpu_to_be16(12345); 301 sa.sin_addr.s_addr = cpu_to_be32(0x7f000001); 302 303 test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr); 304 test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa); 305 sa.sin_addr.s_addr = cpu_to_be32(0x01020304); 306 test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa); 307 } 308 309 static void __init 310 ip6(void) 311 { 312 } 313 314 static void __init 315 ip(void) 316 { 317 ip4(); 318 ip6(); 319 } 320 321 static void __init 322 uuid(void) 323 { 324 const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 325 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf}; 326 327 test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid); 328 test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid); 329 test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid); 330 test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid); 331 } 332 333 static struct dentry test_dentry[4] __initdata = { 334 { .d_parent = &test_dentry[0], 335 .d_name = QSTR_INIT(test_dentry[0].d_iname, 3), 336 .d_iname = "foo" }, 337 { .d_parent = &test_dentry[0], 338 .d_name = QSTR_INIT(test_dentry[1].d_iname, 5), 339 .d_iname = "bravo" }, 340 { .d_parent = &test_dentry[1], 341 .d_name = QSTR_INIT(test_dentry[2].d_iname, 4), 342 .d_iname = "alfa" }, 343 { .d_parent = &test_dentry[2], 344 .d_name = QSTR_INIT(test_dentry[3].d_iname, 5), 345 .d_iname = "romeo" }, 346 }; 347 348 static void __init 349 dentry(void) 350 { 351 test("foo", "%pd", &test_dentry[0]); 352 test("foo", "%pd2", &test_dentry[0]); 353 354 test("romeo", "%pd", &test_dentry[3]); 355 test("alfa/romeo", "%pd2", &test_dentry[3]); 356 test("bravo/alfa/romeo", "%pd3", &test_dentry[3]); 357 test("/bravo/alfa/romeo", "%pd4", &test_dentry[3]); 358 test("/bravo/alfa", "%pd4", &test_dentry[2]); 359 360 test("bravo/alfa |bravo/alfa ", "%-12pd2|%*pd2", &test_dentry[2], -12, &test_dentry[2]); 361 test(" bravo/alfa| bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]); 362 } 363 364 static void __init 365 struct_va_format(void) 366 { 367 } 368 369 static void __init 370 struct_clk(void) 371 { 372 } 373 374 static void __init 375 large_bitmap(void) 376 { 377 const int nbits = 1 << 16; 378 unsigned long *bits = kcalloc(BITS_TO_LONGS(nbits), sizeof(long), GFP_KERNEL); 379 if (!bits) 380 return; 381 382 bitmap_set(bits, 1, 20); 383 bitmap_set(bits, 60000, 15); 384 test("1-20,60000-60014", "%*pbl", nbits, bits); 385 kfree(bits); 386 } 387 388 static void __init 389 bitmap(void) 390 { 391 DECLARE_BITMAP(bits, 20); 392 const int primes[] = {2,3,5,7,11,13,17,19}; 393 int i; 394 395 bitmap_zero(bits, 20); 396 test("00000|00000", "%20pb|%*pb", bits, 20, bits); 397 test("|", "%20pbl|%*pbl", bits, 20, bits); 398 399 for (i = 0; i < ARRAY_SIZE(primes); ++i) 400 set_bit(primes[i], bits); 401 test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits); 402 test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits); 403 404 bitmap_fill(bits, 20); 405 test("fffff|fffff", "%20pb|%*pb", bits, 20, bits); 406 test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits); 407 408 large_bitmap(); 409 } 410 411 static void __init 412 netdev_features(void) 413 { 414 } 415 416 static void __init 417 flags(void) 418 { 419 unsigned long flags; 420 gfp_t gfp; 421 char *cmp_buffer; 422 423 flags = 0; 424 test("", "%pGp", &flags); 425 426 /* Page flags should filter the zone id */ 427 flags = 1UL << NR_PAGEFLAGS; 428 test("", "%pGp", &flags); 429 430 flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru 431 | 1UL << PG_active | 1UL << PG_swapbacked; 432 test("uptodate|dirty|lru|active|swapbacked", "%pGp", &flags); 433 434 435 flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC 436 | VM_DENYWRITE; 437 test("read|exec|mayread|maywrite|mayexec|denywrite", "%pGv", &flags); 438 439 gfp = GFP_TRANSHUGE; 440 test("GFP_TRANSHUGE", "%pGg", &gfp); 441 442 gfp = GFP_ATOMIC|__GFP_DMA; 443 test("GFP_ATOMIC|GFP_DMA", "%pGg", &gfp); 444 445 gfp = __GFP_ATOMIC; 446 test("__GFP_ATOMIC", "%pGg", &gfp); 447 448 cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL); 449 if (!cmp_buffer) 450 return; 451 452 /* Any flags not translated by the table should remain numeric */ 453 gfp = ~__GFP_BITS_MASK; 454 snprintf(cmp_buffer, BUF_SIZE, "%#lx", (unsigned long) gfp); 455 test(cmp_buffer, "%pGg", &gfp); 456 457 snprintf(cmp_buffer, BUF_SIZE, "__GFP_ATOMIC|%#lx", 458 (unsigned long) gfp); 459 gfp |= __GFP_ATOMIC; 460 test(cmp_buffer, "%pGg", &gfp); 461 462 kfree(cmp_buffer); 463 } 464 465 static void __init 466 test_pointer(void) 467 { 468 plain(); 469 symbol_ptr(); 470 kernel_ptr(); 471 struct_resource(); 472 addr(); 473 escaped_str(); 474 hex_string(); 475 mac(); 476 ip(); 477 uuid(); 478 dentry(); 479 struct_va_format(); 480 struct_clk(); 481 bitmap(); 482 netdev_features(); 483 flags(); 484 } 485 486 static int __init 487 test_printf_init(void) 488 { 489 alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL); 490 if (!alloced_buffer) 491 return -ENOMEM; 492 test_buffer = alloced_buffer + PAD_SIZE; 493 494 test_basic(); 495 test_number(); 496 test_string(); 497 test_pointer(); 498 499 kfree(alloced_buffer); 500 501 if (failed_tests == 0) 502 pr_info("all %u tests passed\n", total_tests); 503 else 504 pr_warn("failed %u out of %u tests\n", failed_tests, total_tests); 505 506 return failed_tests ? -EINVAL : 0; 507 } 508 509 module_init(test_printf_init); 510 511 MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>"); 512 MODULE_LICENSE("GPL"); 513