1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Test cases for printf facility. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/init.h> 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/printk.h> 12 #include <linux/random.h> 13 #include <linux/rtc.h> 14 #include <linux/slab.h> 15 #include <linux/string.h> 16 17 #include <linux/bitmap.h> 18 #include <linux/dcache.h> 19 #include <linux/socket.h> 20 #include <linux/in.h> 21 22 #include <linux/gfp.h> 23 #include <linux/mm.h> 24 25 #include "../tools/testing/selftests/kselftest_module.h" 26 27 #define BUF_SIZE 256 28 #define PAD_SIZE 16 29 #define FILL_CHAR '$' 30 31 static unsigned total_tests __initdata; 32 static unsigned failed_tests __initdata; 33 static char *test_buffer __initdata; 34 static char *alloced_buffer __initdata; 35 36 static int __printf(4, 0) __init 37 do_test(int bufsize, const char *expect, int elen, 38 const char *fmt, va_list ap) 39 { 40 va_list aq; 41 int ret, written; 42 43 total_tests++; 44 45 memset(alloced_buffer, FILL_CHAR, BUF_SIZE + 2*PAD_SIZE); 46 va_copy(aq, ap); 47 ret = vsnprintf(test_buffer, bufsize, fmt, aq); 48 va_end(aq); 49 50 if (ret != elen) { 51 pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n", 52 bufsize, fmt, ret, elen); 53 return 1; 54 } 55 56 if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) { 57 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt); 58 return 1; 59 } 60 61 if (!bufsize) { 62 if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) { 63 pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n", 64 fmt); 65 return 1; 66 } 67 return 0; 68 } 69 70 written = min(bufsize-1, elen); 71 if (test_buffer[written]) { 72 pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n", 73 bufsize, fmt); 74 return 1; 75 } 76 77 if (memchr_inv(test_buffer + written + 1, FILL_CHAR, BUF_SIZE + PAD_SIZE - (written + 1))) { 78 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n", 79 bufsize, fmt); 80 return 1; 81 } 82 83 if (memcmp(test_buffer, expect, written)) { 84 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n", 85 bufsize, fmt, test_buffer, written, expect); 86 return 1; 87 } 88 return 0; 89 } 90 91 static void __printf(3, 4) __init 92 __test(const char *expect, int elen, const char *fmt, ...) 93 { 94 va_list ap; 95 int rand; 96 char *p; 97 98 if (elen >= BUF_SIZE) { 99 pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n", 100 elen, fmt); 101 failed_tests++; 102 return; 103 } 104 105 va_start(ap, fmt); 106 107 /* 108 * Every fmt+args is subjected to four tests: Three where we 109 * tell vsnprintf varying buffer sizes (plenty, not quite 110 * enough and 0), and then we also test that kvasprintf would 111 * be able to print it as expected. 112 */ 113 failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap); 114 rand = 1 + prandom_u32_max(elen+1); 115 /* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */ 116 failed_tests += do_test(rand, expect, elen, fmt, ap); 117 failed_tests += do_test(0, expect, elen, fmt, ap); 118 119 p = kvasprintf(GFP_KERNEL, fmt, ap); 120 if (p) { 121 total_tests++; 122 if (memcmp(p, expect, elen+1)) { 123 pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n", 124 fmt, p, expect); 125 failed_tests++; 126 } 127 kfree(p); 128 } 129 va_end(ap); 130 } 131 132 #define test(expect, fmt, ...) \ 133 __test(expect, strlen(expect), fmt, ##__VA_ARGS__) 134 135 static void __init 136 test_basic(void) 137 { 138 /* Work around annoying "warning: zero-length gnu_printf format string". */ 139 char nul = '\0'; 140 141 test("", &nul); 142 test("100%", "100%%"); 143 test("xxx%yyy", "xxx%cyyy", '%'); 144 __test("xxx\0yyy", 7, "xxx%cyyy", '\0'); 145 } 146 147 static void __init 148 test_number(void) 149 { 150 test("0x1234abcd ", "%#-12x", 0x1234abcd); 151 test(" 0x1234abcd", "%#12x", 0x1234abcd); 152 test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234); 153 test("0|1|1|128|255", "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1); 154 test("0|1|1|-128|-1", "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1); 155 test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627); 156 /* 157 * POSIX/C99: »The result of converting zero with an explicit 158 * precision of zero shall be no characters.« Hence the output 159 * from the below test should really be "00|0||| ". However, 160 * the kernel's printf also produces a single 0 in that 161 * case. This test case simply documents the current 162 * behaviour. 163 */ 164 test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0); 165 #ifndef __CHAR_UNSIGNED__ 166 { 167 /* 168 * Passing a 'char' to a %02x specifier doesn't do 169 * what was presumably the intention when char is 170 * signed and the value is negative. One must either & 171 * with 0xff or cast to u8. 172 */ 173 char val = -16; 174 test("0xfffffff0|0xf0|0xf0", "%#02x|%#02x|%#02x", val, val & 0xff, (u8)val); 175 } 176 #endif 177 } 178 179 static void __init 180 test_string(void) 181 { 182 test("", "%s%.0s", "", "123"); 183 test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456"); 184 test("1 | 2|3 | 4|5 ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5"); 185 test("1234 ", "%-10.4s", "123456"); 186 test(" 1234", "%10.4s", "123456"); 187 /* 188 * POSIX and C99 say that a negative precision (which is only 189 * possible to pass via a * argument) should be treated as if 190 * the precision wasn't present, and that if the precision is 191 * omitted (as in %.s), the precision should be taken to be 192 * 0. However, the kernel's printf behave exactly opposite, 193 * treating a negative precision as 0 and treating an omitted 194 * precision specifier as if no precision was given. 195 * 196 * These test cases document the current behaviour; should 197 * anyone ever feel the need to follow the standards more 198 * closely, this can be revisited. 199 */ 200 test(" ", "%4.*s", -5, "123456"); 201 test("123456", "%.s", "123456"); 202 test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c"); 203 test("a | | ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c"); 204 } 205 206 #define PLAIN_BUF_SIZE 64 /* leave some space so we don't oops */ 207 208 #if BITS_PER_LONG == 64 209 210 #define PTR_WIDTH 16 211 #define PTR ((void *)0xffff0123456789abUL) 212 #define PTR_STR "ffff0123456789ab" 213 #define PTR_VAL_NO_CRNG "(____ptrval____)" 214 #define ZEROS "00000000" /* hex 32 zero bits */ 215 216 static int __init 217 plain_format(void) 218 { 219 char buf[PLAIN_BUF_SIZE]; 220 int nchars; 221 222 nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR); 223 224 if (nchars != PTR_WIDTH) 225 return -1; 226 227 if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) { 228 pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"", 229 PTR_VAL_NO_CRNG); 230 return 0; 231 } 232 233 if (strncmp(buf, ZEROS, strlen(ZEROS)) != 0) 234 return -1; 235 236 return 0; 237 } 238 239 #else 240 241 #define PTR_WIDTH 8 242 #define PTR ((void *)0x456789ab) 243 #define PTR_STR "456789ab" 244 #define PTR_VAL_NO_CRNG "(ptrval)" 245 #define ZEROS "" 246 247 static int __init 248 plain_format(void) 249 { 250 /* Format is implicitly tested for 32 bit machines by plain_hash() */ 251 return 0; 252 } 253 254 #endif /* BITS_PER_LONG == 64 */ 255 256 static int __init 257 plain_hash_to_buffer(const void *p, char *buf, size_t len) 258 { 259 int nchars; 260 261 nchars = snprintf(buf, len, "%p", p); 262 263 if (nchars != PTR_WIDTH) 264 return -1; 265 266 if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) { 267 pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"", 268 PTR_VAL_NO_CRNG); 269 return 0; 270 } 271 272 return 0; 273 } 274 275 static int __init 276 plain_hash(void) 277 { 278 char buf[PLAIN_BUF_SIZE]; 279 int ret; 280 281 ret = plain_hash_to_buffer(PTR, buf, PLAIN_BUF_SIZE); 282 if (ret) 283 return ret; 284 285 if (strncmp(buf, PTR_STR, PTR_WIDTH) == 0) 286 return -1; 287 288 return 0; 289 } 290 291 /* 292 * We can't use test() to test %p because we don't know what output to expect 293 * after an address is hashed. 294 */ 295 static void __init 296 plain(void) 297 { 298 int err; 299 300 err = plain_hash(); 301 if (err) { 302 pr_warn("plain 'p' does not appear to be hashed\n"); 303 failed_tests++; 304 return; 305 } 306 307 err = plain_format(); 308 if (err) { 309 pr_warn("hashing plain 'p' has unexpected format\n"); 310 failed_tests++; 311 } 312 } 313 314 static void __init 315 test_hashed(const char *fmt, const void *p) 316 { 317 char buf[PLAIN_BUF_SIZE]; 318 int ret; 319 320 /* 321 * No need to increase failed test counter since this is assumed 322 * to be called after plain(). 323 */ 324 ret = plain_hash_to_buffer(p, buf, PLAIN_BUF_SIZE); 325 if (ret) 326 return; 327 328 test(buf, fmt, p); 329 } 330 331 static void __init 332 null_pointer(void) 333 { 334 test_hashed("%p", NULL); 335 test(ZEROS "00000000", "%px", NULL); 336 test("(null)", "%pE", NULL); 337 } 338 339 #define PTR_INVALID ((void *)0x000000ab) 340 341 static void __init 342 invalid_pointer(void) 343 { 344 test_hashed("%p", PTR_INVALID); 345 test(ZEROS "000000ab", "%px", PTR_INVALID); 346 test("(efault)", "%pE", PTR_INVALID); 347 } 348 349 static void __init 350 symbol_ptr(void) 351 { 352 } 353 354 static void __init 355 kernel_ptr(void) 356 { 357 /* We can't test this without access to kptr_restrict. */ 358 } 359 360 static void __init 361 struct_resource(void) 362 { 363 } 364 365 static void __init 366 addr(void) 367 { 368 } 369 370 static void __init 371 escaped_str(void) 372 { 373 } 374 375 static void __init 376 hex_string(void) 377 { 378 const char buf[3] = {0xc0, 0xff, 0xee}; 379 380 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 381 "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf); 382 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 383 "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf); 384 } 385 386 static void __init 387 mac(void) 388 { 389 const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05}; 390 391 test("2d:48:d6:fc:7a:05", "%pM", addr); 392 test("05:7a:fc:d6:48:2d", "%pMR", addr); 393 test("2d-48-d6-fc-7a-05", "%pMF", addr); 394 test("2d48d6fc7a05", "%pm", addr); 395 test("057afcd6482d", "%pmR", addr); 396 } 397 398 static void __init 399 ip4(void) 400 { 401 struct sockaddr_in sa; 402 403 sa.sin_family = AF_INET; 404 sa.sin_port = cpu_to_be16(12345); 405 sa.sin_addr.s_addr = cpu_to_be32(0x7f000001); 406 407 test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr); 408 test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa); 409 sa.sin_addr.s_addr = cpu_to_be32(0x01020304); 410 test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa); 411 } 412 413 static void __init 414 ip6(void) 415 { 416 } 417 418 static void __init 419 ip(void) 420 { 421 ip4(); 422 ip6(); 423 } 424 425 static void __init 426 uuid(void) 427 { 428 const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 429 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf}; 430 431 test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid); 432 test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid); 433 test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid); 434 test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid); 435 } 436 437 static struct dentry test_dentry[4] __initdata = { 438 { .d_parent = &test_dentry[0], 439 .d_name = QSTR_INIT(test_dentry[0].d_iname, 3), 440 .d_iname = "foo" }, 441 { .d_parent = &test_dentry[0], 442 .d_name = QSTR_INIT(test_dentry[1].d_iname, 5), 443 .d_iname = "bravo" }, 444 { .d_parent = &test_dentry[1], 445 .d_name = QSTR_INIT(test_dentry[2].d_iname, 4), 446 .d_iname = "alfa" }, 447 { .d_parent = &test_dentry[2], 448 .d_name = QSTR_INIT(test_dentry[3].d_iname, 5), 449 .d_iname = "romeo" }, 450 }; 451 452 static void __init 453 dentry(void) 454 { 455 test("foo", "%pd", &test_dentry[0]); 456 test("foo", "%pd2", &test_dentry[0]); 457 458 test("(null)", "%pd", NULL); 459 test("(efault)", "%pd", PTR_INVALID); 460 test("(null)", "%pD", NULL); 461 test("(efault)", "%pD", PTR_INVALID); 462 463 test("romeo", "%pd", &test_dentry[3]); 464 test("alfa/romeo", "%pd2", &test_dentry[3]); 465 test("bravo/alfa/romeo", "%pd3", &test_dentry[3]); 466 test("/bravo/alfa/romeo", "%pd4", &test_dentry[3]); 467 test("/bravo/alfa", "%pd4", &test_dentry[2]); 468 469 test("bravo/alfa |bravo/alfa ", "%-12pd2|%*pd2", &test_dentry[2], -12, &test_dentry[2]); 470 test(" bravo/alfa| bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]); 471 } 472 473 static void __init 474 struct_va_format(void) 475 { 476 } 477 478 static void __init 479 struct_rtc_time(void) 480 { 481 /* 1543210543 */ 482 const struct rtc_time tm = { 483 .tm_sec = 43, 484 .tm_min = 35, 485 .tm_hour = 5, 486 .tm_mday = 26, 487 .tm_mon = 10, 488 .tm_year = 118, 489 }; 490 491 test("(%ptR?)", "%pt", &tm); 492 test("2018-11-26T05:35:43", "%ptR", &tm); 493 test("0118-10-26T05:35:43", "%ptRr", &tm); 494 test("05:35:43|2018-11-26", "%ptRt|%ptRd", &tm, &tm); 495 test("05:35:43|0118-10-26", "%ptRtr|%ptRdr", &tm, &tm); 496 test("05:35:43|2018-11-26", "%ptRttr|%ptRdtr", &tm, &tm); 497 test("05:35:43 tr|2018-11-26 tr", "%ptRt tr|%ptRd tr", &tm, &tm); 498 } 499 500 static void __init 501 struct_clk(void) 502 { 503 } 504 505 static void __init 506 large_bitmap(void) 507 { 508 const int nbits = 1 << 16; 509 unsigned long *bits = bitmap_zalloc(nbits, GFP_KERNEL); 510 if (!bits) 511 return; 512 513 bitmap_set(bits, 1, 20); 514 bitmap_set(bits, 60000, 15); 515 test("1-20,60000-60014", "%*pbl", nbits, bits); 516 bitmap_free(bits); 517 } 518 519 static void __init 520 bitmap(void) 521 { 522 DECLARE_BITMAP(bits, 20); 523 const int primes[] = {2,3,5,7,11,13,17,19}; 524 int i; 525 526 bitmap_zero(bits, 20); 527 test("00000|00000", "%20pb|%*pb", bits, 20, bits); 528 test("|", "%20pbl|%*pbl", bits, 20, bits); 529 530 for (i = 0; i < ARRAY_SIZE(primes); ++i) 531 set_bit(primes[i], bits); 532 test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits); 533 test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits); 534 535 bitmap_fill(bits, 20); 536 test("fffff|fffff", "%20pb|%*pb", bits, 20, bits); 537 test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits); 538 539 large_bitmap(); 540 } 541 542 static void __init 543 netdev_features(void) 544 { 545 } 546 547 static void __init 548 flags(void) 549 { 550 unsigned long flags; 551 gfp_t gfp; 552 char *cmp_buffer; 553 554 flags = 0; 555 test("", "%pGp", &flags); 556 557 /* Page flags should filter the zone id */ 558 flags = 1UL << NR_PAGEFLAGS; 559 test("", "%pGp", &flags); 560 561 flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru 562 | 1UL << PG_active | 1UL << PG_swapbacked; 563 test("uptodate|dirty|lru|active|swapbacked", "%pGp", &flags); 564 565 566 flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC 567 | VM_DENYWRITE; 568 test("read|exec|mayread|maywrite|mayexec|denywrite", "%pGv", &flags); 569 570 gfp = GFP_TRANSHUGE; 571 test("GFP_TRANSHUGE", "%pGg", &gfp); 572 573 gfp = GFP_ATOMIC|__GFP_DMA; 574 test("GFP_ATOMIC|GFP_DMA", "%pGg", &gfp); 575 576 gfp = __GFP_ATOMIC; 577 test("__GFP_ATOMIC", "%pGg", &gfp); 578 579 cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL); 580 if (!cmp_buffer) 581 return; 582 583 /* Any flags not translated by the table should remain numeric */ 584 gfp = ~__GFP_BITS_MASK; 585 snprintf(cmp_buffer, BUF_SIZE, "%#lx", (unsigned long) gfp); 586 test(cmp_buffer, "%pGg", &gfp); 587 588 snprintf(cmp_buffer, BUF_SIZE, "__GFP_ATOMIC|%#lx", 589 (unsigned long) gfp); 590 gfp |= __GFP_ATOMIC; 591 test(cmp_buffer, "%pGg", &gfp); 592 593 kfree(cmp_buffer); 594 } 595 596 static void __init 597 test_pointer(void) 598 { 599 plain(); 600 null_pointer(); 601 invalid_pointer(); 602 symbol_ptr(); 603 kernel_ptr(); 604 struct_resource(); 605 addr(); 606 escaped_str(); 607 hex_string(); 608 mac(); 609 ip(); 610 uuid(); 611 dentry(); 612 struct_va_format(); 613 struct_rtc_time(); 614 struct_clk(); 615 bitmap(); 616 netdev_features(); 617 flags(); 618 } 619 620 static void __init selftest(void) 621 { 622 alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL); 623 if (!alloced_buffer) 624 return; 625 test_buffer = alloced_buffer + PAD_SIZE; 626 627 test_basic(); 628 test_number(); 629 test_string(); 630 test_pointer(); 631 632 kfree(alloced_buffer); 633 } 634 635 KSTM_MODULE_LOADERS(test_printf); 636 MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>"); 637 MODULE_LICENSE("GPL"); 638