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 <linux/property.h> 26 27 #include "../tools/testing/selftests/kselftest_module.h" 28 29 #define BUF_SIZE 256 30 #define PAD_SIZE 16 31 #define FILL_CHAR '$' 32 33 static unsigned total_tests __initdata; 34 static unsigned failed_tests __initdata; 35 static char *test_buffer __initdata; 36 static char *alloced_buffer __initdata; 37 38 static int __printf(4, 0) __init 39 do_test(int bufsize, const char *expect, int elen, 40 const char *fmt, va_list ap) 41 { 42 va_list aq; 43 int ret, written; 44 45 total_tests++; 46 47 memset(alloced_buffer, FILL_CHAR, BUF_SIZE + 2*PAD_SIZE); 48 va_copy(aq, ap); 49 ret = vsnprintf(test_buffer, bufsize, fmt, aq); 50 va_end(aq); 51 52 if (ret != elen) { 53 pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n", 54 bufsize, fmt, ret, elen); 55 return 1; 56 } 57 58 if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) { 59 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt); 60 return 1; 61 } 62 63 if (!bufsize) { 64 if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_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 (memchr_inv(test_buffer + written + 1, FILL_CHAR, BUF_SIZE + PAD_SIZE - (written + 1))) { 80 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n", 81 bufsize, fmt); 82 return 1; 83 } 84 85 if (memcmp(test_buffer, expect, written)) { 86 pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n", 87 bufsize, fmt, test_buffer, written, expect); 88 return 1; 89 } 90 return 0; 91 } 92 93 static void __printf(3, 4) __init 94 __test(const char *expect, int elen, const char *fmt, ...) 95 { 96 va_list ap; 97 int rand; 98 char *p; 99 100 if (elen >= BUF_SIZE) { 101 pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n", 102 elen, fmt); 103 failed_tests++; 104 return; 105 } 106 107 va_start(ap, fmt); 108 109 /* 110 * Every fmt+args is subjected to four tests: Three where we 111 * tell vsnprintf varying buffer sizes (plenty, not quite 112 * enough and 0), and then we also test that kvasprintf would 113 * be able to print it as expected. 114 */ 115 failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap); 116 rand = 1 + prandom_u32_max(elen+1); 117 /* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */ 118 failed_tests += do_test(rand, expect, elen, fmt, ap); 119 failed_tests += do_test(0, expect, elen, fmt, ap); 120 121 p = kvasprintf(GFP_KERNEL, fmt, ap); 122 if (p) { 123 total_tests++; 124 if (memcmp(p, expect, elen+1)) { 125 pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n", 126 fmt, p, expect); 127 failed_tests++; 128 } 129 kfree(p); 130 } 131 va_end(ap); 132 } 133 134 #define test(expect, fmt, ...) \ 135 __test(expect, strlen(expect), fmt, ##__VA_ARGS__) 136 137 static void __init 138 test_basic(void) 139 { 140 /* Work around annoying "warning: zero-length gnu_printf format string". */ 141 char nul = '\0'; 142 143 test("", &nul); 144 test("100%", "100%%"); 145 test("xxx%yyy", "xxx%cyyy", '%'); 146 __test("xxx\0yyy", 7, "xxx%cyyy", '\0'); 147 } 148 149 static void __init 150 test_number(void) 151 { 152 test("0x1234abcd ", "%#-12x", 0x1234abcd); 153 test(" 0x1234abcd", "%#12x", 0x1234abcd); 154 test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234); 155 test("0|1|1|128|255", "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1); 156 test("0|1|1|-128|-1", "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1); 157 test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627); 158 /* 159 * POSIX/C99: »The result of converting zero with an explicit 160 * precision of zero shall be no characters.« Hence the output 161 * from the below test should really be "00|0||| ". However, 162 * the kernel's printf also produces a single 0 in that 163 * case. This test case simply documents the current 164 * behaviour. 165 */ 166 test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0); 167 #ifndef __CHAR_UNSIGNED__ 168 { 169 /* 170 * Passing a 'char' to a %02x specifier doesn't do 171 * what was presumably the intention when char is 172 * signed and the value is negative. One must either & 173 * with 0xff or cast to u8. 174 */ 175 char val = -16; 176 test("0xfffffff0|0xf0|0xf0", "%#02x|%#02x|%#02x", val, val & 0xff, (u8)val); 177 } 178 #endif 179 } 180 181 static void __init 182 test_string(void) 183 { 184 test("", "%s%.0s", "", "123"); 185 test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456"); 186 test("1 | 2|3 | 4|5 ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5"); 187 test("1234 ", "%-10.4s", "123456"); 188 test(" 1234", "%10.4s", "123456"); 189 /* 190 * POSIX and C99 say that a negative precision (which is only 191 * possible to pass via a * argument) should be treated as if 192 * the precision wasn't present, and that if the precision is 193 * omitted (as in %.s), the precision should be taken to be 194 * 0. However, the kernel's printf behave exactly opposite, 195 * treating a negative precision as 0 and treating an omitted 196 * precision specifier as if no precision was given. 197 * 198 * These test cases document the current behaviour; should 199 * anyone ever feel the need to follow the standards more 200 * closely, this can be revisited. 201 */ 202 test(" ", "%4.*s", -5, "123456"); 203 test("123456", "%.s", "123456"); 204 test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c"); 205 test("a | | ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c"); 206 } 207 208 #define PLAIN_BUF_SIZE 64 /* leave some space so we don't oops */ 209 210 #if BITS_PER_LONG == 64 211 212 #define PTR_WIDTH 16 213 #define PTR ((void *)0xffff0123456789abUL) 214 #define PTR_STR "ffff0123456789ab" 215 #define PTR_VAL_NO_CRNG "(____ptrval____)" 216 #define ZEROS "00000000" /* hex 32 zero bits */ 217 218 static int __init 219 plain_format(void) 220 { 221 char buf[PLAIN_BUF_SIZE]; 222 int nchars; 223 224 nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR); 225 226 if (nchars != PTR_WIDTH) 227 return -1; 228 229 if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) { 230 pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"", 231 PTR_VAL_NO_CRNG); 232 return 0; 233 } 234 235 if (strncmp(buf, ZEROS, strlen(ZEROS)) != 0) 236 return -1; 237 238 return 0; 239 } 240 241 #else 242 243 #define PTR_WIDTH 8 244 #define PTR ((void *)0x456789ab) 245 #define PTR_STR "456789ab" 246 #define PTR_VAL_NO_CRNG "(ptrval)" 247 #define ZEROS "" 248 249 static int __init 250 plain_format(void) 251 { 252 /* Format is implicitly tested for 32 bit machines by plain_hash() */ 253 return 0; 254 } 255 256 #endif /* BITS_PER_LONG == 64 */ 257 258 static int __init 259 plain_hash_to_buffer(const void *p, char *buf, size_t len) 260 { 261 int nchars; 262 263 nchars = snprintf(buf, len, "%p", p); 264 265 if (nchars != PTR_WIDTH) 266 return -1; 267 268 if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) { 269 pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"", 270 PTR_VAL_NO_CRNG); 271 return 0; 272 } 273 274 return 0; 275 } 276 277 static int __init 278 plain_hash(void) 279 { 280 char buf[PLAIN_BUF_SIZE]; 281 int ret; 282 283 ret = plain_hash_to_buffer(PTR, buf, PLAIN_BUF_SIZE); 284 if (ret) 285 return ret; 286 287 if (strncmp(buf, PTR_STR, PTR_WIDTH) == 0) 288 return -1; 289 290 return 0; 291 } 292 293 /* 294 * We can't use test() to test %p because we don't know what output to expect 295 * after an address is hashed. 296 */ 297 static void __init 298 plain(void) 299 { 300 int err; 301 302 err = plain_hash(); 303 if (err) { 304 pr_warn("plain 'p' does not appear to be hashed\n"); 305 failed_tests++; 306 return; 307 } 308 309 err = plain_format(); 310 if (err) { 311 pr_warn("hashing plain 'p' has unexpected format\n"); 312 failed_tests++; 313 } 314 } 315 316 static void __init 317 test_hashed(const char *fmt, const void *p) 318 { 319 char buf[PLAIN_BUF_SIZE]; 320 int ret; 321 322 /* 323 * No need to increase failed test counter since this is assumed 324 * to be called after plain(). 325 */ 326 ret = plain_hash_to_buffer(p, buf, PLAIN_BUF_SIZE); 327 if (ret) 328 return; 329 330 test(buf, fmt, p); 331 } 332 333 static void __init 334 null_pointer(void) 335 { 336 test_hashed("%p", NULL); 337 test(ZEROS "00000000", "%px", NULL); 338 test("(null)", "%pE", NULL); 339 } 340 341 #define PTR_INVALID ((void *)0x000000ab) 342 343 static void __init 344 invalid_pointer(void) 345 { 346 test_hashed("%p", PTR_INVALID); 347 test(ZEROS "000000ab", "%px", PTR_INVALID); 348 test("(efault)", "%pE", PTR_INVALID); 349 } 350 351 static void __init 352 symbol_ptr(void) 353 { 354 } 355 356 static void __init 357 kernel_ptr(void) 358 { 359 /* We can't test this without access to kptr_restrict. */ 360 } 361 362 static void __init 363 struct_resource(void) 364 { 365 } 366 367 static void __init 368 addr(void) 369 { 370 } 371 372 static void __init 373 escaped_str(void) 374 { 375 } 376 377 static void __init 378 hex_string(void) 379 { 380 const char buf[3] = {0xc0, 0xff, 0xee}; 381 382 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 383 "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf); 384 test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", 385 "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf); 386 } 387 388 static void __init 389 mac(void) 390 { 391 const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05}; 392 393 test("2d:48:d6:fc:7a:05", "%pM", addr); 394 test("05:7a:fc:d6:48:2d", "%pMR", addr); 395 test("2d-48-d6-fc-7a-05", "%pMF", addr); 396 test("2d48d6fc7a05", "%pm", addr); 397 test("057afcd6482d", "%pmR", addr); 398 } 399 400 static void __init 401 ip4(void) 402 { 403 struct sockaddr_in sa; 404 405 sa.sin_family = AF_INET; 406 sa.sin_port = cpu_to_be16(12345); 407 sa.sin_addr.s_addr = cpu_to_be32(0x7f000001); 408 409 test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr); 410 test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa); 411 sa.sin_addr.s_addr = cpu_to_be32(0x01020304); 412 test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa); 413 } 414 415 static void __init 416 ip6(void) 417 { 418 } 419 420 static void __init 421 ip(void) 422 { 423 ip4(); 424 ip6(); 425 } 426 427 static void __init 428 uuid(void) 429 { 430 const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 431 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf}; 432 433 test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid); 434 test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid); 435 test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid); 436 test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid); 437 } 438 439 static struct dentry test_dentry[4] __initdata = { 440 { .d_parent = &test_dentry[0], 441 .d_name = QSTR_INIT(test_dentry[0].d_iname, 3), 442 .d_iname = "foo" }, 443 { .d_parent = &test_dentry[0], 444 .d_name = QSTR_INIT(test_dentry[1].d_iname, 5), 445 .d_iname = "bravo" }, 446 { .d_parent = &test_dentry[1], 447 .d_name = QSTR_INIT(test_dentry[2].d_iname, 4), 448 .d_iname = "alfa" }, 449 { .d_parent = &test_dentry[2], 450 .d_name = QSTR_INIT(test_dentry[3].d_iname, 5), 451 .d_iname = "romeo" }, 452 }; 453 454 static void __init 455 dentry(void) 456 { 457 test("foo", "%pd", &test_dentry[0]); 458 test("foo", "%pd2", &test_dentry[0]); 459 460 test("(null)", "%pd", NULL); 461 test("(efault)", "%pd", PTR_INVALID); 462 test("(null)", "%pD", NULL); 463 test("(efault)", "%pD", PTR_INVALID); 464 465 test("romeo", "%pd", &test_dentry[3]); 466 test("alfa/romeo", "%pd2", &test_dentry[3]); 467 test("bravo/alfa/romeo", "%pd3", &test_dentry[3]); 468 test("/bravo/alfa/romeo", "%pd4", &test_dentry[3]); 469 test("/bravo/alfa", "%pd4", &test_dentry[2]); 470 471 test("bravo/alfa |bravo/alfa ", "%-12pd2|%*pd2", &test_dentry[2], -12, &test_dentry[2]); 472 test(" bravo/alfa| bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]); 473 } 474 475 static void __init 476 struct_va_format(void) 477 { 478 } 479 480 static void __init 481 struct_rtc_time(void) 482 { 483 /* 1543210543 */ 484 const struct rtc_time tm = { 485 .tm_sec = 43, 486 .tm_min = 35, 487 .tm_hour = 5, 488 .tm_mday = 26, 489 .tm_mon = 10, 490 .tm_year = 118, 491 }; 492 493 test("(%ptR?)", "%pt", &tm); 494 test("2018-11-26T05:35:43", "%ptR", &tm); 495 test("0118-10-26T05:35:43", "%ptRr", &tm); 496 test("05:35:43|2018-11-26", "%ptRt|%ptRd", &tm, &tm); 497 test("05:35:43|0118-10-26", "%ptRtr|%ptRdr", &tm, &tm); 498 test("05:35:43|2018-11-26", "%ptRttr|%ptRdtr", &tm, &tm); 499 test("05:35:43 tr|2018-11-26 tr", "%ptRt tr|%ptRd tr", &tm, &tm); 500 } 501 502 static void __init 503 struct_clk(void) 504 { 505 } 506 507 static void __init 508 large_bitmap(void) 509 { 510 const int nbits = 1 << 16; 511 unsigned long *bits = bitmap_zalloc(nbits, GFP_KERNEL); 512 if (!bits) 513 return; 514 515 bitmap_set(bits, 1, 20); 516 bitmap_set(bits, 60000, 15); 517 test("1-20,60000-60014", "%*pbl", nbits, bits); 518 bitmap_free(bits); 519 } 520 521 static void __init 522 bitmap(void) 523 { 524 DECLARE_BITMAP(bits, 20); 525 const int primes[] = {2,3,5,7,11,13,17,19}; 526 int i; 527 528 bitmap_zero(bits, 20); 529 test("00000|00000", "%20pb|%*pb", bits, 20, bits); 530 test("|", "%20pbl|%*pbl", bits, 20, bits); 531 532 for (i = 0; i < ARRAY_SIZE(primes); ++i) 533 set_bit(primes[i], bits); 534 test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits); 535 test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits); 536 537 bitmap_fill(bits, 20); 538 test("fffff|fffff", "%20pb|%*pb", bits, 20, bits); 539 test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits); 540 541 large_bitmap(); 542 } 543 544 static void __init 545 netdev_features(void) 546 { 547 } 548 549 static void __init 550 flags(void) 551 { 552 unsigned long flags; 553 gfp_t gfp; 554 char *cmp_buffer; 555 556 flags = 0; 557 test("", "%pGp", &flags); 558 559 /* Page flags should filter the zone id */ 560 flags = 1UL << NR_PAGEFLAGS; 561 test("", "%pGp", &flags); 562 563 flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru 564 | 1UL << PG_active | 1UL << PG_swapbacked; 565 test("uptodate|dirty|lru|active|swapbacked", "%pGp", &flags); 566 567 568 flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC 569 | VM_DENYWRITE; 570 test("read|exec|mayread|maywrite|mayexec|denywrite", "%pGv", &flags); 571 572 gfp = GFP_TRANSHUGE; 573 test("GFP_TRANSHUGE", "%pGg", &gfp); 574 575 gfp = GFP_ATOMIC|__GFP_DMA; 576 test("GFP_ATOMIC|GFP_DMA", "%pGg", &gfp); 577 578 gfp = __GFP_ATOMIC; 579 test("__GFP_ATOMIC", "%pGg", &gfp); 580 581 cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL); 582 if (!cmp_buffer) 583 return; 584 585 /* Any flags not translated by the table should remain numeric */ 586 gfp = ~__GFP_BITS_MASK; 587 snprintf(cmp_buffer, BUF_SIZE, "%#lx", (unsigned long) gfp); 588 test(cmp_buffer, "%pGg", &gfp); 589 590 snprintf(cmp_buffer, BUF_SIZE, "__GFP_ATOMIC|%#lx", 591 (unsigned long) gfp); 592 gfp |= __GFP_ATOMIC; 593 test(cmp_buffer, "%pGg", &gfp); 594 595 kfree(cmp_buffer); 596 } 597 598 static void __init fwnode_pointer(void) 599 { 600 const struct software_node softnodes[] = { 601 { .name = "first", }, 602 { .name = "second", .parent = &softnodes[0], }, 603 { .name = "third", .parent = &softnodes[1], }, 604 { NULL /* Guardian */ } 605 }; 606 const char * const full_name = "first/second/third"; 607 const char * const full_name_second = "first/second"; 608 const char * const second_name = "second"; 609 const char * const third_name = "third"; 610 int rval; 611 612 rval = software_node_register_nodes(softnodes); 613 if (rval) { 614 pr_warn("cannot register softnodes; rval %d\n", rval); 615 return; 616 } 617 618 test(full_name_second, "%pfw", software_node_fwnode(&softnodes[1])); 619 test(full_name, "%pfw", software_node_fwnode(&softnodes[2])); 620 test(full_name, "%pfwf", software_node_fwnode(&softnodes[2])); 621 test(second_name, "%pfwP", software_node_fwnode(&softnodes[1])); 622 test(third_name, "%pfwP", software_node_fwnode(&softnodes[2])); 623 624 software_node_unregister_nodes(softnodes); 625 } 626 627 static void __init 628 errptr(void) 629 { 630 test("-1234", "%pe", ERR_PTR(-1234)); 631 632 /* Check that %pe with a non-ERR_PTR gets treated as ordinary %p. */ 633 BUILD_BUG_ON(IS_ERR(PTR)); 634 test_hashed("%pe", PTR); 635 636 #ifdef CONFIG_SYMBOLIC_ERRNAME 637 test("(-ENOTSOCK)", "(%pe)", ERR_PTR(-ENOTSOCK)); 638 test("(-EAGAIN)", "(%pe)", ERR_PTR(-EAGAIN)); 639 BUILD_BUG_ON(EAGAIN != EWOULDBLOCK); 640 test("(-EAGAIN)", "(%pe)", ERR_PTR(-EWOULDBLOCK)); 641 test("[-EIO ]", "[%-8pe]", ERR_PTR(-EIO)); 642 test("[ -EIO]", "[%8pe]", ERR_PTR(-EIO)); 643 test("-EPROBE_DEFER", "%pe", ERR_PTR(-EPROBE_DEFER)); 644 #endif 645 } 646 647 static void __init 648 test_pointer(void) 649 { 650 plain(); 651 null_pointer(); 652 invalid_pointer(); 653 symbol_ptr(); 654 kernel_ptr(); 655 struct_resource(); 656 addr(); 657 escaped_str(); 658 hex_string(); 659 mac(); 660 ip(); 661 uuid(); 662 dentry(); 663 struct_va_format(); 664 struct_rtc_time(); 665 struct_clk(); 666 bitmap(); 667 netdev_features(); 668 flags(); 669 errptr(); 670 fwnode_pointer(); 671 } 672 673 static void __init selftest(void) 674 { 675 alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL); 676 if (!alloced_buffer) 677 return; 678 test_buffer = alloced_buffer + PAD_SIZE; 679 680 test_basic(); 681 test_number(); 682 test_string(); 683 test_pointer(); 684 685 kfree(alloced_buffer); 686 } 687 688 KSTM_MODULE_LOADERS(test_printf); 689 MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>"); 690 MODULE_LICENSE("GPL"); 691