1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/lib/vsprintf.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 */ 7 8 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ 9 /* 10 * Wirzenius wrote this portably, Torvalds fucked it up :-) 11 */ 12 13 /* 14 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com> 15 * - changed to provide snprintf and vsnprintf functions 16 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> 17 * - scnprintf and vscnprintf 18 */ 19 20 #include <linux/stdarg.h> 21 #include <linux/build_bug.h> 22 #include <linux/clk.h> 23 #include <linux/clk-provider.h> 24 #include <linux/errname.h> 25 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */ 26 #include <linux/types.h> 27 #include <linux/string.h> 28 #include <linux/ctype.h> 29 #include <linux/hex.h> 30 #include <linux/kernel.h> 31 #include <linux/kallsyms.h> 32 #include <linux/math64.h> 33 #include <linux/uaccess.h> 34 #include <linux/ioport.h> 35 #include <linux/dcache.h> 36 #include <linux/cred.h> 37 #include <linux/rtc.h> 38 #include <linux/sprintf.h> 39 #include <linux/time.h> 40 #include <linux/uuid.h> 41 #include <linux/of.h> 42 #include <net/addrconf.h> 43 #include <linux/siphash.h> 44 #include <linux/compiler.h> 45 #include <linux/property.h> 46 #include <linux/notifier.h> 47 #ifdef CONFIG_BLOCK 48 #include <linux/blkdev.h> 49 #endif 50 51 #include "../mm/internal.h" /* For the trace_print_flags arrays */ 52 53 #include <asm/page.h> /* for PAGE_SIZE */ 54 #include <asm/byteorder.h> /* cpu_to_le16 */ 55 #include <linux/unaligned.h> 56 57 #include <linux/string_helpers.h> 58 #include "kstrtox.h" 59 60 /* Disable pointer hashing if requested */ 61 bool no_hash_pointers __ro_after_init; 62 EXPORT_SYMBOL_GPL(no_hash_pointers); 63 64 /* 65 * Hashed pointers policy selected by "hash_pointers=..." boot param 66 * 67 * `auto` - Hashed pointers enabled unless disabled by slub_debug_enabled=true 68 * `always` - Hashed pointers enabled unconditionally 69 * `never` - Hashed pointers disabled unconditionally 70 */ 71 enum hash_pointers_policy { 72 HASH_PTR_AUTO = 0, 73 HASH_PTR_ALWAYS, 74 HASH_PTR_NEVER 75 }; 76 static enum hash_pointers_policy hash_pointers_mode __initdata; 77 78 noinline 79 static unsigned long long simple_strntoull(const char *startp, char **endp, unsigned int base, size_t max_chars) 80 { 81 const char *cp; 82 unsigned long long result = 0ULL; 83 size_t prefix_chars; 84 unsigned int rv; 85 86 cp = _parse_integer_fixup_radix(startp, &base); 87 prefix_chars = cp - startp; 88 if (prefix_chars < max_chars) { 89 rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); 90 /* FIXME */ 91 cp += (rv & ~KSTRTOX_OVERFLOW); 92 } else { 93 /* Field too short for prefix + digit, skip over without converting */ 94 cp = startp + max_chars; 95 } 96 97 if (endp) 98 *endp = (char *)cp; 99 100 return result; 101 } 102 103 /** 104 * simple_strtoull - convert a string to an unsigned long long 105 * @cp: The start of the string 106 * @endp: A pointer to the end of the parsed string will be placed here 107 * @base: The number base to use 108 * 109 * This function has caveats. Please use kstrtoull instead. 110 */ 111 noinline 112 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 113 { 114 return simple_strntoull(cp, endp, base, INT_MAX); 115 } 116 EXPORT_SYMBOL(simple_strtoull); 117 118 /** 119 * simple_strtoul - convert a string to an unsigned long 120 * @cp: The start of the string 121 * @endp: A pointer to the end of the parsed string will be placed here 122 * @base: The number base to use 123 * 124 * This function has caveats. Please use kstrtoul instead. 125 */ 126 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 127 { 128 return simple_strtoull(cp, endp, base); 129 } 130 EXPORT_SYMBOL(simple_strtoul); 131 132 /** 133 * simple_strtol - convert a string to a signed long 134 * @cp: The start of the string 135 * @endp: A pointer to the end of the parsed string will be placed here 136 * @base: The number base to use 137 * 138 * This function has caveats. Please use kstrtol instead. 139 */ 140 long simple_strtol(const char *cp, char **endp, unsigned int base) 141 { 142 if (*cp == '-') 143 return -simple_strtoul(cp + 1, endp, base); 144 145 return simple_strtoul(cp, endp, base); 146 } 147 EXPORT_SYMBOL(simple_strtol); 148 149 noinline 150 static long long simple_strntoll(const char *cp, char **endp, unsigned int base, size_t max_chars) 151 { 152 /* 153 * simple_strntoull() safely handles receiving max_chars==0 in the 154 * case cp[0] == '-' && max_chars == 1. 155 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 156 * and the content of *cp is irrelevant. 157 */ 158 if (*cp == '-' && max_chars > 0) 159 return -simple_strntoull(cp + 1, endp, base, max_chars - 1); 160 161 return simple_strntoull(cp, endp, base, max_chars); 162 } 163 164 /** 165 * simple_strtoll - convert a string to a signed long long 166 * @cp: The start of the string 167 * @endp: A pointer to the end of the parsed string will be placed here 168 * @base: The number base to use 169 * 170 * This function has caveats. Please use kstrtoll instead. 171 */ 172 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 173 { 174 return simple_strntoll(cp, endp, base, INT_MAX); 175 } 176 EXPORT_SYMBOL(simple_strtoll); 177 178 static inline int skip_atoi(const char **s) 179 { 180 int i = 0; 181 182 do { 183 i = i*10 + *((*s)++) - '0'; 184 } while (isdigit(**s)); 185 186 return i; 187 } 188 189 /* 190 * Decimal conversion is by far the most typical, and is used for 191 * /proc and /sys data. This directly impacts e.g. top performance 192 * with many processes running. We optimize it for speed by emitting 193 * two characters at a time, using a 200 byte lookup table. This 194 * roughly halves the number of multiplications compared to computing 195 * the digits one at a time. Implementation strongly inspired by the 196 * previous version, which in turn used ideas described at 197 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 198 * from the author, Douglas W. Jones). 199 * 200 * It turns out there is precisely one 26 bit fixed-point 201 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 202 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 203 * range happens to be somewhat larger (x <= 1073741898), but that's 204 * irrelevant for our purpose. 205 * 206 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 207 * need a 32x32->64 bit multiply, so we simply use the same constant. 208 * 209 * For dividing a number in the range [100, 10^4-1] by 100, there are 210 * several options. The simplest is (x * 0x147b) >> 19, which is valid 211 * for all x <= 43698. 212 */ 213 214 static const u16 decpair[100] = { 215 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 216 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 217 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 218 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 219 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 220 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 221 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 222 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 223 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 224 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 225 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 226 #undef _ 227 }; 228 229 /* 230 * This will print a single '0' even if r == 0, since we would 231 * immediately jump to out_r where two 0s would be written but only 232 * one of them accounted for in buf. This is needed by ip4_string 233 * below. All other callers pass a non-zero value of r. 234 */ 235 static noinline_for_stack 236 char *put_dec_trunc8(char *buf, unsigned r) 237 { 238 unsigned q; 239 240 /* 1 <= r < 10^8 */ 241 if (r < 100) 242 goto out_r; 243 244 /* 100 <= r < 10^8 */ 245 q = (r * (u64)0x28f5c29) >> 32; 246 *((u16 *)buf) = decpair[r - 100*q]; 247 buf += 2; 248 249 /* 1 <= q < 10^6 */ 250 if (q < 100) 251 goto out_q; 252 253 /* 100 <= q < 10^6 */ 254 r = (q * (u64)0x28f5c29) >> 32; 255 *((u16 *)buf) = decpair[q - 100*r]; 256 buf += 2; 257 258 /* 1 <= r < 10^4 */ 259 if (r < 100) 260 goto out_r; 261 262 /* 100 <= r < 10^4 */ 263 q = (r * 0x147b) >> 19; 264 *((u16 *)buf) = decpair[r - 100*q]; 265 buf += 2; 266 out_q: 267 /* 1 <= q < 100 */ 268 r = q; 269 out_r: 270 /* 1 <= r < 100 */ 271 *((u16 *)buf) = decpair[r]; 272 buf += r < 10 ? 1 : 2; 273 return buf; 274 } 275 276 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 277 static noinline_for_stack 278 char *put_dec_full8(char *buf, unsigned r) 279 { 280 unsigned q; 281 282 /* 0 <= r < 10^8 */ 283 q = (r * (u64)0x28f5c29) >> 32; 284 *((u16 *)buf) = decpair[r - 100*q]; 285 buf += 2; 286 287 /* 0 <= q < 10^6 */ 288 r = (q * (u64)0x28f5c29) >> 32; 289 *((u16 *)buf) = decpair[q - 100*r]; 290 buf += 2; 291 292 /* 0 <= r < 10^4 */ 293 q = (r * 0x147b) >> 19; 294 *((u16 *)buf) = decpair[r - 100*q]; 295 buf += 2; 296 297 /* 0 <= q < 100 */ 298 *((u16 *)buf) = decpair[q]; 299 buf += 2; 300 return buf; 301 } 302 303 static noinline_for_stack 304 char *put_dec(char *buf, unsigned long long n) 305 { 306 if (n >= 100*1000*1000) 307 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 308 /* 1 <= n <= 1.6e11 */ 309 if (n >= 100*1000*1000) 310 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 311 /* 1 <= n < 1e8 */ 312 return put_dec_trunc8(buf, n); 313 } 314 315 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 316 317 static void 318 put_dec_full4(char *buf, unsigned r) 319 { 320 unsigned q; 321 322 /* 0 <= r < 10^4 */ 323 q = (r * 0x147b) >> 19; 324 *((u16 *)buf) = decpair[r - 100*q]; 325 buf += 2; 326 /* 0 <= q < 100 */ 327 *((u16 *)buf) = decpair[q]; 328 } 329 330 /* 331 * Call put_dec_full4 on x % 10000, return x / 10000. 332 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 333 * holds for all x < 1,128,869,999. The largest value this 334 * helper will ever be asked to convert is 1,125,520,955. 335 * (second call in the put_dec code, assuming n is all-ones). 336 */ 337 static noinline_for_stack 338 unsigned put_dec_helper4(char *buf, unsigned x) 339 { 340 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 341 342 put_dec_full4(buf, x - q * 10000); 343 return q; 344 } 345 346 /* Based on code by Douglas W. Jones found at 347 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 348 * (with permission from the author). 349 * Performs no 64-bit division and hence should be fast on 32-bit machines. 350 */ 351 static 352 char *put_dec(char *buf, unsigned long long n) 353 { 354 uint32_t d3, d2, d1, q, h; 355 356 if (n < 100*1000*1000) 357 return put_dec_trunc8(buf, n); 358 359 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 360 h = (n >> 32); 361 d2 = (h ) & 0xffff; 362 d3 = (h >> 16); /* implicit "& 0xffff" */ 363 364 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 365 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 366 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 367 q = put_dec_helper4(buf, q); 368 369 q += 7671 * d3 + 9496 * d2 + 6 * d1; 370 q = put_dec_helper4(buf+4, q); 371 372 q += 4749 * d3 + 42 * d2; 373 q = put_dec_helper4(buf+8, q); 374 375 q += 281 * d3; 376 buf += 12; 377 if (q) 378 buf = put_dec_trunc8(buf, q); 379 else while (buf[-1] == '0') 380 --buf; 381 382 return buf; 383 } 384 385 #endif 386 387 /* 388 * Convert passed number to decimal string. 389 * Returns the length of string. On buffer overflow, returns 0. 390 * 391 * If speed is not important, use snprintf(). It's easy to read the code. 392 */ 393 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 394 { 395 /* put_dec requires 2-byte alignment of the buffer. */ 396 char tmp[sizeof(num) * 3] __aligned(2); 397 int idx, len; 398 399 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 400 if (num <= 9) { 401 tmp[0] = '0' + num; 402 len = 1; 403 } else { 404 len = put_dec(tmp, num) - tmp; 405 } 406 407 if (len > size || width > size) 408 return 0; 409 410 if (width > len) { 411 width = width - len; 412 for (idx = 0; idx < width; idx++) 413 buf[idx] = ' '; 414 } else { 415 width = 0; 416 } 417 418 for (idx = 0; idx < len; ++idx) 419 buf[idx + width] = tmp[len - idx - 1]; 420 421 return len + width; 422 } 423 424 #define SIGN 1 /* unsigned/signed */ 425 #define LEFT 2 /* left justified */ 426 #define PLUS 4 /* show plus */ 427 #define SPACE 8 /* space if plus */ 428 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 429 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 430 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 431 432 static_assert(ZEROPAD == ('0' - ' ')); 433 static_assert(SMALL == ('a' ^ 'A')); 434 435 enum format_state { 436 FORMAT_STATE_NONE, /* Just a string part */ 437 FORMAT_STATE_NUM, 438 FORMAT_STATE_WIDTH, 439 FORMAT_STATE_PRECISION, 440 FORMAT_STATE_CHAR, 441 FORMAT_STATE_STR, 442 FORMAT_STATE_PTR, 443 FORMAT_STATE_PERCENT_CHAR, 444 FORMAT_STATE_INVALID, 445 }; 446 447 struct printf_spec { 448 unsigned char flags; /* flags to number() */ 449 unsigned char base; /* number base, 8, 10 or 16 only */ 450 short precision; /* # of digits/chars */ 451 int field_width; /* width of output field */ 452 } __packed; 453 static_assert(sizeof(struct printf_spec) == 8); 454 455 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 456 #define PRECISION_MAX ((1 << 15) - 1) 457 458 static noinline_for_stack 459 char *number(char *buf, char *end, unsigned long long num, 460 struct printf_spec spec) 461 { 462 /* put_dec requires 2-byte alignment of the buffer. */ 463 char tmp[3 * sizeof(num)] __aligned(2); 464 char sign; 465 char locase; 466 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 467 int i; 468 bool is_zero = num == 0LL; 469 int field_width = spec.field_width; 470 int precision = spec.precision; 471 472 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 473 * produces same digits or (maybe lowercased) letters */ 474 locase = (spec.flags & SMALL); 475 if (spec.flags & LEFT) 476 spec.flags &= ~ZEROPAD; 477 sign = 0; 478 if (spec.flags & SIGN) { 479 if ((signed long long)num < 0) { 480 sign = '-'; 481 num = -(signed long long)num; 482 field_width--; 483 } else if (spec.flags & PLUS) { 484 sign = '+'; 485 field_width--; 486 } else if (spec.flags & SPACE) { 487 sign = ' '; 488 field_width--; 489 } 490 } 491 if (need_pfx) { 492 if (spec.base == 16) 493 field_width -= 2; 494 else if (!is_zero) 495 field_width--; 496 } 497 498 /* generate full string in tmp[], in reverse order */ 499 i = 0; 500 if (num < spec.base) 501 tmp[i++] = hex_asc_upper[num] | locase; 502 else if (spec.base != 10) { /* 8 or 16 */ 503 int mask = spec.base - 1; 504 int shift = 3; 505 506 if (spec.base == 16) 507 shift = 4; 508 do { 509 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 510 num >>= shift; 511 } while (num); 512 } else { /* base 10 */ 513 i = put_dec(tmp, num) - tmp; 514 } 515 516 /* printing 100 using %2d gives "100", not "00" */ 517 if (i > precision) 518 precision = i; 519 /* leading space padding */ 520 field_width -= precision; 521 if (!(spec.flags & (ZEROPAD | LEFT))) { 522 while (--field_width >= 0) { 523 if (buf < end) 524 *buf = ' '; 525 ++buf; 526 } 527 } 528 /* sign */ 529 if (sign) { 530 if (buf < end) 531 *buf = sign; 532 ++buf; 533 } 534 /* "0x" / "0" prefix */ 535 if (need_pfx) { 536 if (spec.base == 16 || !is_zero) { 537 if (buf < end) 538 *buf = '0'; 539 ++buf; 540 } 541 if (spec.base == 16) { 542 if (buf < end) 543 *buf = ('X' | locase); 544 ++buf; 545 } 546 } 547 /* zero or space padding */ 548 if (!(spec.flags & LEFT)) { 549 char c = ' ' + (spec.flags & ZEROPAD); 550 551 while (--field_width >= 0) { 552 if (buf < end) 553 *buf = c; 554 ++buf; 555 } 556 } 557 /* hmm even more zero padding? */ 558 while (i <= --precision) { 559 if (buf < end) 560 *buf = '0'; 561 ++buf; 562 } 563 /* actual digits of result */ 564 while (--i >= 0) { 565 if (buf < end) 566 *buf = tmp[i]; 567 ++buf; 568 } 569 /* trailing space padding */ 570 while (--field_width >= 0) { 571 if (buf < end) 572 *buf = ' '; 573 ++buf; 574 } 575 576 return buf; 577 } 578 579 #define special_hex_spec(size) \ 580 (struct printf_spec) { \ 581 .field_width = 2 + 2 * (size), /* 0x + hex */ \ 582 .flags = SPECIAL | SMALL | ZEROPAD, \ 583 .base = 16, \ 584 .precision = -1, \ 585 } 586 587 static noinline_for_stack 588 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 589 { 590 return number(buf, end, num, special_hex_spec(size)); 591 } 592 593 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 594 { 595 size_t size; 596 if (buf >= end) /* nowhere to put anything */ 597 return; 598 size = end - buf; 599 if (size <= spaces) { 600 memset(buf, ' ', size); 601 return; 602 } 603 if (len) { 604 if (len > size - spaces) 605 len = size - spaces; 606 memmove(buf + spaces, buf, len); 607 } 608 memset(buf, ' ', spaces); 609 } 610 611 /* 612 * Handle field width padding for a string. 613 * @buf: current buffer position 614 * @n: length of string 615 * @end: end of output buffer 616 * @spec: for field width and flags 617 * Returns: new buffer position after padding. 618 */ 619 static noinline_for_stack 620 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 621 { 622 unsigned spaces; 623 624 if (likely(n >= spec.field_width)) 625 return buf; 626 /* we want to pad the sucker */ 627 spaces = spec.field_width - n; 628 if (!(spec.flags & LEFT)) { 629 move_right(buf - n, end, n, spaces); 630 return buf + spaces; 631 } 632 while (spaces--) { 633 if (buf < end) 634 *buf = ' '; 635 ++buf; 636 } 637 return buf; 638 } 639 640 /* Handle string from a well known address. */ 641 static char *string_nocheck(char *buf, char *end, const char *s, 642 struct printf_spec spec) 643 { 644 int len = 0; 645 int lim = spec.precision; 646 647 while (lim--) { 648 char c = *s++; 649 if (!c) 650 break; 651 if (buf < end) 652 *buf = c; 653 ++buf; 654 ++len; 655 } 656 return widen_string(buf, len, end, spec); 657 } 658 659 static char *err_ptr(char *buf, char *end, void *ptr, 660 struct printf_spec spec) 661 { 662 int err = PTR_ERR(ptr); 663 const char *sym = errname(err); 664 665 if (sym) 666 return string_nocheck(buf, end, sym, spec); 667 668 /* 669 * Somebody passed ERR_PTR(-1234) or some other non-existing 670 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 671 * printing it as its decimal representation. 672 */ 673 spec.flags |= SIGN; 674 spec.base = 10; 675 return number(buf, end, err, spec); 676 } 677 678 /* Be careful: error messages must fit into the given buffer. */ 679 static char *error_string(char *buf, char *end, const char *s, 680 struct printf_spec spec) 681 { 682 /* 683 * Hard limit to avoid a completely insane messages. It actually 684 * works pretty well because most error messages are in 685 * the many pointer format modifiers. 686 */ 687 if (spec.precision == -1) 688 spec.precision = 2 * sizeof(void *); 689 690 return string_nocheck(buf, end, s, spec); 691 } 692 693 /* 694 * Do not call any complex external code here. Nested printk()/vsprintf() 695 * might cause infinite loops. Failures might break printk() and would 696 * be hard to debug. 697 */ 698 static const char *check_pointer_msg(const void *ptr) 699 { 700 if (!ptr) 701 return "(null)"; 702 703 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 704 return "(efault)"; 705 706 return NULL; 707 } 708 709 static int check_pointer(char **buf, char *end, const void *ptr, 710 struct printf_spec spec) 711 { 712 const char *err_msg; 713 714 err_msg = check_pointer_msg(ptr); 715 if (err_msg) { 716 *buf = error_string(*buf, end, err_msg, spec); 717 return -EFAULT; 718 } 719 720 return 0; 721 } 722 723 static noinline_for_stack 724 char *string(char *buf, char *end, const char *s, 725 struct printf_spec spec) 726 { 727 if (check_pointer(&buf, end, s, spec)) 728 return buf; 729 730 return string_nocheck(buf, end, s, spec); 731 } 732 733 static char *pointer_string(char *buf, char *end, 734 const void *ptr, 735 struct printf_spec spec) 736 { 737 spec.base = 16; 738 spec.flags |= SMALL; 739 if (spec.field_width == -1) { 740 spec.field_width = 2 * sizeof(ptr); 741 spec.flags |= ZEROPAD; 742 } 743 744 return number(buf, end, (unsigned long int)ptr, spec); 745 } 746 747 /* Make pointers available for printing early in the boot sequence. */ 748 static int debug_boot_weak_hash __ro_after_init; 749 750 static int __init debug_boot_weak_hash_enable(char *str) 751 { 752 debug_boot_weak_hash = 1; 753 pr_info("debug_boot_weak_hash enabled\n"); 754 return 0; 755 } 756 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 757 758 static bool filled_random_ptr_key __read_mostly; 759 static siphash_key_t ptr_key __read_mostly; 760 761 static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) 762 { 763 get_random_bytes(&ptr_key, sizeof(ptr_key)); 764 765 /* Pairs with smp_rmb() before reading ptr_key. */ 766 smp_wmb(); 767 WRITE_ONCE(filled_random_ptr_key, true); 768 return NOTIFY_DONE; 769 } 770 771 static int __init vsprintf_init_hashval(void) 772 { 773 static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; 774 execute_with_initialized_rng(&fill_ptr_key_nb); 775 return 0; 776 } 777 subsys_initcall(vsprintf_init_hashval) 778 779 /* Maps a pointer to a 32 bit unique identifier. */ 780 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 781 { 782 unsigned long hashval; 783 784 if (!READ_ONCE(filled_random_ptr_key)) 785 return -EBUSY; 786 787 /* Pairs with smp_wmb() after writing ptr_key. */ 788 smp_rmb(); 789 790 #ifdef CONFIG_64BIT 791 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 792 /* 793 * Mask off the first 32 bits, this makes explicit that we have 794 * modified the address (and 32 bits is plenty for a unique ID). 795 */ 796 hashval = hashval & 0xffffffff; 797 #else 798 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 799 #endif 800 *hashval_out = hashval; 801 return 0; 802 } 803 804 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 805 { 806 return __ptr_to_hashval(ptr, hashval_out); 807 } 808 809 static char *ptr_to_id(char *buf, char *end, const void *ptr, 810 struct printf_spec spec) 811 { 812 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 813 unsigned long hashval; 814 int ret; 815 816 /* 817 * Print the real pointer value for NULL and error pointers, 818 * as they are not actual addresses. 819 */ 820 if (IS_ERR_OR_NULL(ptr)) 821 return pointer_string(buf, end, ptr, spec); 822 823 /* When debugging early boot use non-cryptographically secure hash. */ 824 if (unlikely(debug_boot_weak_hash)) { 825 hashval = hash_long((unsigned long)ptr, 32); 826 return pointer_string(buf, end, (const void *)hashval, spec); 827 } 828 829 ret = __ptr_to_hashval(ptr, &hashval); 830 if (ret) { 831 spec.field_width = 2 * sizeof(ptr); 832 /* string length must be less than default_width */ 833 return error_string(buf, end, str, spec); 834 } 835 836 return pointer_string(buf, end, (const void *)hashval, spec); 837 } 838 839 static char *default_pointer(char *buf, char *end, const void *ptr, 840 struct printf_spec spec) 841 { 842 /* 843 * default is to _not_ leak addresses, so hash before printing, 844 * unless no_hash_pointers is specified on the command line. 845 */ 846 if (unlikely(no_hash_pointers)) 847 return pointer_string(buf, end, ptr, spec); 848 849 return ptr_to_id(buf, end, ptr, spec); 850 } 851 852 int kptr_restrict __read_mostly; 853 854 static noinline_for_stack 855 char *restricted_pointer(char *buf, char *end, const void *ptr, 856 struct printf_spec spec) 857 { 858 switch (kptr_restrict) { 859 case 0: 860 /* Handle as %p, hash and do _not_ leak addresses. */ 861 return default_pointer(buf, end, ptr, spec); 862 case 1: { 863 const struct cred *cred; 864 865 /* 866 * kptr_restrict==1 cannot be used in IRQ context 867 * because its test for CAP_SYSLOG would be meaningless. 868 */ 869 if (in_hardirq() || in_serving_softirq() || in_nmi()) { 870 if (spec.field_width == -1) 871 spec.field_width = 2 * sizeof(ptr); 872 return error_string(buf, end, "pK-error", spec); 873 } 874 875 /* 876 * Only print the real pointer value if the current 877 * process has CAP_SYSLOG and is running with the 878 * same credentials it started with. This is because 879 * access to files is checked at open() time, but %pK 880 * checks permission at read() time. We don't want to 881 * leak pointer values if a binary opens a file using 882 * %pK and then elevates privileges before reading it. 883 */ 884 cred = current_cred(); 885 if (!has_capability_noaudit(current, CAP_SYSLOG) || 886 !uid_eq(cred->euid, cred->uid) || 887 !gid_eq(cred->egid, cred->gid)) 888 ptr = NULL; 889 break; 890 } 891 case 2: 892 default: 893 /* Always print 0's for %pK */ 894 ptr = NULL; 895 break; 896 } 897 898 return pointer_string(buf, end, ptr, spec); 899 } 900 901 static noinline_for_stack 902 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 903 const char *fmt) 904 { 905 const char *array[4], *s; 906 const struct dentry *p; 907 int depth; 908 int i, n; 909 910 switch (fmt[1]) { 911 case '2': case '3': case '4': 912 depth = fmt[1] - '0'; 913 break; 914 default: 915 depth = 1; 916 } 917 918 rcu_read_lock(); 919 for (i = 0; i < depth; i++, d = p) { 920 if (check_pointer(&buf, end, d, spec)) { 921 rcu_read_unlock(); 922 return buf; 923 } 924 925 p = READ_ONCE(d->d_parent); 926 array[i] = READ_ONCE(d->d_name.name); 927 if (p == d) { 928 if (i) 929 array[i] = ""; 930 i++; 931 break; 932 } 933 } 934 s = array[--i]; 935 for (n = 0; n != spec.precision; n++, buf++) { 936 char c = *s++; 937 if (!c) { 938 if (!i) 939 break; 940 c = '/'; 941 s = array[--i]; 942 } 943 if (buf < end) 944 *buf = c; 945 } 946 rcu_read_unlock(); 947 return widen_string(buf, n, end, spec); 948 } 949 950 static noinline_for_stack 951 char *file_dentry_name(char *buf, char *end, const struct file *f, 952 struct printf_spec spec, const char *fmt) 953 { 954 if (check_pointer(&buf, end, f, spec)) 955 return buf; 956 957 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 958 } 959 #ifdef CONFIG_BLOCK 960 static noinline_for_stack 961 char *bdev_name(char *buf, char *end, struct block_device *bdev, 962 struct printf_spec spec, const char *fmt) 963 { 964 struct gendisk *hd; 965 966 if (check_pointer(&buf, end, bdev, spec)) 967 return buf; 968 969 hd = bdev->bd_disk; 970 buf = string(buf, end, hd->disk_name, spec); 971 if (bdev_is_partition(bdev)) { 972 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 973 if (buf < end) 974 *buf = 'p'; 975 buf++; 976 } 977 buf = number(buf, end, bdev_partno(bdev), spec); 978 } 979 return buf; 980 } 981 #endif 982 983 static noinline_for_stack 984 char *symbol_string(char *buf, char *end, void *ptr, 985 struct printf_spec spec, const char *fmt) 986 { 987 unsigned long value; 988 #ifdef CONFIG_KALLSYMS 989 char sym[KSYM_SYMBOL_LEN]; 990 #endif 991 992 if (fmt[1] == 'R') 993 ptr = __builtin_extract_return_addr(ptr); 994 value = (unsigned long)ptr; 995 996 #ifdef CONFIG_KALLSYMS 997 if (*fmt == 'B' && fmt[1] == 'b') 998 sprint_backtrace_build_id(sym, value); 999 else if (*fmt == 'B') 1000 sprint_backtrace(sym, value); 1001 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 1002 sprint_symbol_build_id(sym, value); 1003 else if (*fmt != 's') 1004 sprint_symbol(sym, value); 1005 else 1006 sprint_symbol_no_offset(sym, value); 1007 1008 return string_nocheck(buf, end, sym, spec); 1009 #else 1010 return special_hex_number(buf, end, value, sizeof(void *)); 1011 #endif 1012 } 1013 1014 static const struct printf_spec default_str_spec = { 1015 .field_width = -1, 1016 .precision = -1, 1017 }; 1018 1019 static const struct printf_spec default_flag_spec = { 1020 .base = 16, 1021 .precision = -1, 1022 .flags = SPECIAL | SMALL, 1023 }; 1024 1025 static const struct printf_spec default_dec_spec = { 1026 .base = 10, 1027 .precision = -1, 1028 }; 1029 1030 static const struct printf_spec default_dec02_spec = { 1031 .base = 10, 1032 .field_width = 2, 1033 .precision = -1, 1034 .flags = ZEROPAD, 1035 }; 1036 1037 static const struct printf_spec default_dec04_spec = { 1038 .base = 10, 1039 .field_width = 4, 1040 .precision = -1, 1041 .flags = ZEROPAD, 1042 }; 1043 1044 static noinline_for_stack 1045 char *hex_range(char *buf, char *end, u64 start_val, u64 end_val, 1046 struct printf_spec spec) 1047 { 1048 buf = number(buf, end, start_val, spec); 1049 if (start_val == end_val) 1050 return buf; 1051 1052 if (buf < end) 1053 *buf = '-'; 1054 ++buf; 1055 return number(buf, end, end_val, spec); 1056 } 1057 1058 static noinline_for_stack 1059 char *resource_string(char *buf, char *end, struct resource *res, 1060 struct printf_spec spec, const char *fmt) 1061 { 1062 #ifndef IO_RSRC_PRINTK_SIZE 1063 #define IO_RSRC_PRINTK_SIZE 6 1064 #endif 1065 1066 #ifndef MEM_RSRC_PRINTK_SIZE 1067 #define MEM_RSRC_PRINTK_SIZE 10 1068 #endif 1069 static const struct printf_spec io_spec = { 1070 .base = 16, 1071 .field_width = IO_RSRC_PRINTK_SIZE, 1072 .precision = -1, 1073 .flags = SPECIAL | SMALL | ZEROPAD, 1074 }; 1075 static const struct printf_spec mem_spec = { 1076 .base = 16, 1077 .field_width = MEM_RSRC_PRINTK_SIZE, 1078 .precision = -1, 1079 .flags = SPECIAL | SMALL | ZEROPAD, 1080 }; 1081 static const struct printf_spec bus_spec = { 1082 .base = 16, 1083 .field_width = 2, 1084 .precision = -1, 1085 .flags = SMALL | ZEROPAD, 1086 }; 1087 static const struct printf_spec str_spec = { 1088 .field_width = -1, 1089 .precision = 10, 1090 .flags = LEFT, 1091 }; 1092 1093 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1094 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1095 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1096 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1097 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1098 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1099 char sym[MAX(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1100 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1101 1102 char *p = sym, *pend = sym + sizeof(sym); 1103 bool decode = fmt[0] == 'R'; 1104 const struct printf_spec *specp; 1105 1106 if (check_pointer(&buf, end, res, spec)) 1107 return buf; 1108 1109 *p++ = '['; 1110 if (res->flags & IORESOURCE_IO) { 1111 p = string_nocheck(p, pend, "io ", str_spec); 1112 specp = &io_spec; 1113 } else if (res->flags & IORESOURCE_MEM) { 1114 p = string_nocheck(p, pend, "mem ", str_spec); 1115 specp = &mem_spec; 1116 } else if (res->flags & IORESOURCE_IRQ) { 1117 p = string_nocheck(p, pend, "irq ", str_spec); 1118 specp = &default_dec_spec; 1119 } else if (res->flags & IORESOURCE_DMA) { 1120 p = string_nocheck(p, pend, "dma ", str_spec); 1121 specp = &default_dec_spec; 1122 } else if (res->flags & IORESOURCE_BUS) { 1123 p = string_nocheck(p, pend, "bus ", str_spec); 1124 specp = &bus_spec; 1125 } else { 1126 p = string_nocheck(p, pend, "??? ", str_spec); 1127 specp = &mem_spec; 1128 decode = false; 1129 } 1130 if (decode && res->flags & IORESOURCE_UNSET) { 1131 p = string_nocheck(p, pend, "size ", str_spec); 1132 p = number(p, pend, resource_size(res), *specp); 1133 } else { 1134 p = hex_range(p, pend, res->start, res->end, *specp); 1135 } 1136 if (decode) { 1137 if (res->flags & IORESOURCE_MEM_64) 1138 p = string_nocheck(p, pend, " 64bit", str_spec); 1139 if (res->flags & IORESOURCE_PREFETCH) 1140 p = string_nocheck(p, pend, " pref", str_spec); 1141 if (res->flags & IORESOURCE_WINDOW) 1142 p = string_nocheck(p, pend, " window", str_spec); 1143 if (res->flags & IORESOURCE_DISABLED) 1144 p = string_nocheck(p, pend, " disabled", str_spec); 1145 } else { 1146 p = string_nocheck(p, pend, " flags ", str_spec); 1147 p = number(p, pend, res->flags, default_flag_spec); 1148 } 1149 *p++ = ']'; 1150 *p = '\0'; 1151 1152 return string_nocheck(buf, end, sym, spec); 1153 } 1154 1155 static noinline_for_stack 1156 char *range_string(char *buf, char *end, const struct range *range, 1157 struct printf_spec spec, const char *fmt) 1158 { 1159 char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")]; 1160 char *p = sym, *pend = sym + sizeof(sym); 1161 1162 if (check_pointer(&buf, end, range, spec)) 1163 return buf; 1164 1165 p = string_nocheck(p, pend, "[range ", default_str_spec); 1166 p = hex_range(p, pend, range->start, range->end, special_hex_spec(sizeof(range->start))); 1167 *p++ = ']'; 1168 *p = '\0'; 1169 1170 return string_nocheck(buf, end, sym, spec); 1171 } 1172 1173 static noinline_for_stack 1174 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1175 const char *fmt) 1176 { 1177 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1178 negative value, fallback to the default */ 1179 char separator; 1180 1181 if (spec.field_width == 0) 1182 /* nothing to print */ 1183 return buf; 1184 1185 if (check_pointer(&buf, end, addr, spec)) 1186 return buf; 1187 1188 switch (fmt[1]) { 1189 case 'C': 1190 separator = ':'; 1191 break; 1192 case 'D': 1193 separator = '-'; 1194 break; 1195 case 'N': 1196 separator = 0; 1197 break; 1198 default: 1199 separator = ' '; 1200 break; 1201 } 1202 1203 if (spec.field_width > 0) 1204 len = min_t(int, spec.field_width, 64); 1205 1206 for (i = 0; i < len; ++i) { 1207 if (buf < end) 1208 *buf = hex_asc_hi(addr[i]); 1209 ++buf; 1210 if (buf < end) 1211 *buf = hex_asc_lo(addr[i]); 1212 ++buf; 1213 1214 if (separator && i != len - 1) { 1215 if (buf < end) 1216 *buf = separator; 1217 ++buf; 1218 } 1219 } 1220 1221 return buf; 1222 } 1223 1224 static noinline_for_stack 1225 char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, 1226 struct printf_spec spec, const char *fmt) 1227 { 1228 const int CHUNKSZ = 32; 1229 int nr_bits = max_t(int, spec.field_width, 0); 1230 int i, chunksz; 1231 bool first = true; 1232 1233 if (check_pointer(&buf, end, bitmap, spec)) 1234 return buf; 1235 1236 /* reused to print numbers */ 1237 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1238 1239 chunksz = nr_bits & (CHUNKSZ - 1); 1240 if (chunksz == 0) 1241 chunksz = CHUNKSZ; 1242 1243 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1244 for (; i >= 0; i -= CHUNKSZ) { 1245 u32 chunkmask, val; 1246 int word, bit; 1247 1248 chunkmask = ((1ULL << chunksz) - 1); 1249 word = i / BITS_PER_LONG; 1250 bit = i % BITS_PER_LONG; 1251 val = (bitmap[word] >> bit) & chunkmask; 1252 1253 if (!first) { 1254 if (buf < end) 1255 *buf = ','; 1256 buf++; 1257 } 1258 first = false; 1259 1260 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1261 buf = number(buf, end, val, spec); 1262 1263 chunksz = CHUNKSZ; 1264 } 1265 return buf; 1266 } 1267 1268 static noinline_for_stack 1269 char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, 1270 struct printf_spec spec, const char *fmt) 1271 { 1272 int nr_bits = max_t(int, spec.field_width, 0); 1273 bool first = true; 1274 int rbot, rtop; 1275 1276 if (check_pointer(&buf, end, bitmap, spec)) 1277 return buf; 1278 1279 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1280 if (!first) { 1281 if (buf < end) 1282 *buf = ','; 1283 buf++; 1284 } 1285 first = false; 1286 1287 buf = number(buf, end, rbot, default_dec_spec); 1288 if (rtop == rbot + 1) 1289 continue; 1290 1291 if (buf < end) 1292 *buf = '-'; 1293 buf = number(++buf, end, rtop - 1, default_dec_spec); 1294 } 1295 return buf; 1296 } 1297 1298 static noinline_for_stack 1299 char *mac_address_string(char *buf, char *end, u8 *addr, 1300 struct printf_spec spec, const char *fmt) 1301 { 1302 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1303 char *p = mac_addr; 1304 int i; 1305 char separator; 1306 bool reversed = false; 1307 1308 if (check_pointer(&buf, end, addr, spec)) 1309 return buf; 1310 1311 switch (fmt[1]) { 1312 case 'F': 1313 separator = '-'; 1314 break; 1315 1316 case 'R': 1317 reversed = true; 1318 fallthrough; 1319 1320 default: 1321 separator = ':'; 1322 break; 1323 } 1324 1325 for (i = 0; i < 6; i++) { 1326 if (reversed) 1327 p = hex_byte_pack(p, addr[5 - i]); 1328 else 1329 p = hex_byte_pack(p, addr[i]); 1330 1331 if (fmt[0] == 'M' && i != 5) 1332 *p++ = separator; 1333 } 1334 *p = '\0'; 1335 1336 return string_nocheck(buf, end, mac_addr, spec); 1337 } 1338 1339 static noinline_for_stack 1340 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1341 { 1342 int i; 1343 bool leading_zeros = (fmt[0] == 'i'); 1344 int index; 1345 int step; 1346 1347 switch (fmt[2]) { 1348 case 'h': 1349 #ifdef __BIG_ENDIAN 1350 index = 0; 1351 step = 1; 1352 #else 1353 index = 3; 1354 step = -1; 1355 #endif 1356 break; 1357 case 'l': 1358 index = 3; 1359 step = -1; 1360 break; 1361 case 'n': 1362 case 'b': 1363 default: 1364 index = 0; 1365 step = 1; 1366 break; 1367 } 1368 for (i = 0; i < 4; i++) { 1369 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1370 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1371 if (leading_zeros) { 1372 if (digits < 3) 1373 *p++ = '0'; 1374 if (digits < 2) 1375 *p++ = '0'; 1376 } 1377 /* reverse the digits in the quad */ 1378 while (digits--) 1379 *p++ = temp[digits]; 1380 if (i < 3) 1381 *p++ = '.'; 1382 index += step; 1383 } 1384 *p = '\0'; 1385 1386 return p; 1387 } 1388 1389 static noinline_for_stack 1390 char *ip6_compressed_string(char *p, const char *addr) 1391 { 1392 int i, j, range; 1393 unsigned char zerolength[8]; 1394 int longest = 1; 1395 int colonpos = -1; 1396 u16 word; 1397 u8 hi, lo; 1398 bool needcolon = false; 1399 bool useIPv4; 1400 struct in6_addr in6; 1401 1402 memcpy(&in6, addr, sizeof(struct in6_addr)); 1403 1404 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1405 1406 memset(zerolength, 0, sizeof(zerolength)); 1407 1408 if (useIPv4) 1409 range = 6; 1410 else 1411 range = 8; 1412 1413 /* find position of longest 0 run */ 1414 for (i = 0; i < range; i++) { 1415 for (j = i; j < range; j++) { 1416 if (in6.s6_addr16[j] != 0) 1417 break; 1418 zerolength[i]++; 1419 } 1420 } 1421 for (i = 0; i < range; i++) { 1422 if (zerolength[i] > longest) { 1423 longest = zerolength[i]; 1424 colonpos = i; 1425 } 1426 } 1427 if (longest == 1) /* don't compress a single 0 */ 1428 colonpos = -1; 1429 1430 /* emit address */ 1431 for (i = 0; i < range; i++) { 1432 if (i == colonpos) { 1433 if (needcolon || i == 0) 1434 *p++ = ':'; 1435 *p++ = ':'; 1436 needcolon = false; 1437 i += longest - 1; 1438 continue; 1439 } 1440 if (needcolon) { 1441 *p++ = ':'; 1442 needcolon = false; 1443 } 1444 /* hex u16 without leading 0s */ 1445 word = ntohs(in6.s6_addr16[i]); 1446 hi = word >> 8; 1447 lo = word & 0xff; 1448 if (hi) { 1449 if (hi > 0x0f) 1450 p = hex_byte_pack(p, hi); 1451 else 1452 *p++ = hex_asc_lo(hi); 1453 p = hex_byte_pack(p, lo); 1454 } 1455 else if (lo > 0x0f) 1456 p = hex_byte_pack(p, lo); 1457 else 1458 *p++ = hex_asc_lo(lo); 1459 needcolon = true; 1460 } 1461 1462 if (useIPv4) { 1463 if (needcolon) 1464 *p++ = ':'; 1465 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1466 } 1467 *p = '\0'; 1468 1469 return p; 1470 } 1471 1472 static noinline_for_stack 1473 char *ip6_string(char *p, const char *addr, const char *fmt) 1474 { 1475 int i; 1476 1477 for (i = 0; i < 8; i++) { 1478 p = hex_byte_pack(p, *addr++); 1479 p = hex_byte_pack(p, *addr++); 1480 if (fmt[0] == 'I' && i != 7) 1481 *p++ = ':'; 1482 } 1483 *p = '\0'; 1484 1485 return p; 1486 } 1487 1488 static noinline_for_stack 1489 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1490 struct printf_spec spec, const char *fmt) 1491 { 1492 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1493 1494 if (fmt[0] == 'I' && fmt[2] == 'c') 1495 ip6_compressed_string(ip6_addr, addr); 1496 else 1497 ip6_string(ip6_addr, addr, fmt); 1498 1499 return string_nocheck(buf, end, ip6_addr, spec); 1500 } 1501 1502 static noinline_for_stack 1503 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1504 struct printf_spec spec, const char *fmt) 1505 { 1506 char ip4_addr[sizeof("255.255.255.255")]; 1507 1508 ip4_string(ip4_addr, addr, fmt); 1509 1510 return string_nocheck(buf, end, ip4_addr, spec); 1511 } 1512 1513 static noinline_for_stack 1514 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1515 struct printf_spec spec, const char *fmt) 1516 { 1517 bool have_p = false, have_s = false, have_f = false, have_c = false; 1518 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1519 sizeof(":12345") + sizeof("/123456789") + 1520 sizeof("%1234567890")]; 1521 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1522 const u8 *addr = (const u8 *) &sa->sin6_addr; 1523 char fmt6[2] = { fmt[0], '6' }; 1524 u8 off = 0; 1525 1526 fmt++; 1527 while (isalpha(*++fmt)) { 1528 switch (*fmt) { 1529 case 'p': 1530 have_p = true; 1531 break; 1532 case 'f': 1533 have_f = true; 1534 break; 1535 case 's': 1536 have_s = true; 1537 break; 1538 case 'c': 1539 have_c = true; 1540 break; 1541 } 1542 } 1543 1544 if (have_p || have_s || have_f) { 1545 *p = '['; 1546 off = 1; 1547 } 1548 1549 if (fmt6[0] == 'I' && have_c) 1550 p = ip6_compressed_string(ip6_addr + off, addr); 1551 else 1552 p = ip6_string(ip6_addr + off, addr, fmt6); 1553 1554 if (have_p || have_s || have_f) 1555 *p++ = ']'; 1556 1557 if (have_p) { 1558 *p++ = ':'; 1559 p = number(p, pend, ntohs(sa->sin6_port), spec); 1560 } 1561 if (have_f) { 1562 *p++ = '/'; 1563 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1564 IPV6_FLOWINFO_MASK), spec); 1565 } 1566 if (have_s) { 1567 *p++ = '%'; 1568 p = number(p, pend, sa->sin6_scope_id, spec); 1569 } 1570 *p = '\0'; 1571 1572 return string_nocheck(buf, end, ip6_addr, spec); 1573 } 1574 1575 static noinline_for_stack 1576 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1577 struct printf_spec spec, const char *fmt) 1578 { 1579 bool have_p = false; 1580 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1581 char *pend = ip4_addr + sizeof(ip4_addr); 1582 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1583 char fmt4[3] = { fmt[0], '4', 0 }; 1584 1585 fmt++; 1586 while (isalpha(*++fmt)) { 1587 switch (*fmt) { 1588 case 'p': 1589 have_p = true; 1590 break; 1591 case 'h': 1592 case 'l': 1593 case 'n': 1594 case 'b': 1595 fmt4[2] = *fmt; 1596 break; 1597 } 1598 } 1599 1600 p = ip4_string(ip4_addr, addr, fmt4); 1601 if (have_p) { 1602 *p++ = ':'; 1603 p = number(p, pend, ntohs(sa->sin_port), spec); 1604 } 1605 *p = '\0'; 1606 1607 return string_nocheck(buf, end, ip4_addr, spec); 1608 } 1609 1610 static noinline_for_stack 1611 char *ip_addr_string(char *buf, char *end, const void *ptr, 1612 struct printf_spec spec, const char *fmt) 1613 { 1614 char *err_fmt_msg; 1615 1616 if (check_pointer(&buf, end, ptr, spec)) 1617 return buf; 1618 1619 switch (fmt[1]) { 1620 case '6': 1621 return ip6_addr_string(buf, end, ptr, spec, fmt); 1622 case '4': 1623 return ip4_addr_string(buf, end, ptr, spec, fmt); 1624 case 'S': { 1625 const union { 1626 struct sockaddr raw; 1627 struct sockaddr_in v4; 1628 struct sockaddr_in6 v6; 1629 } *sa = ptr; 1630 1631 switch (sa->raw.sa_family) { 1632 case AF_INET: 1633 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1634 case AF_INET6: 1635 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1636 default: 1637 return error_string(buf, end, "(einval)", spec); 1638 }} 1639 } 1640 1641 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1642 return error_string(buf, end, err_fmt_msg, spec); 1643 } 1644 1645 static noinline_for_stack 1646 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1647 const char *fmt) 1648 { 1649 bool found = true; 1650 int count = 1; 1651 unsigned int flags = 0; 1652 int len; 1653 1654 if (spec.field_width == 0) 1655 return buf; /* nothing to print */ 1656 1657 if (check_pointer(&buf, end, addr, spec)) 1658 return buf; 1659 1660 do { 1661 switch (fmt[count++]) { 1662 case 'a': 1663 flags |= ESCAPE_ANY; 1664 break; 1665 case 'c': 1666 flags |= ESCAPE_SPECIAL; 1667 break; 1668 case 'h': 1669 flags |= ESCAPE_HEX; 1670 break; 1671 case 'n': 1672 flags |= ESCAPE_NULL; 1673 break; 1674 case 'o': 1675 flags |= ESCAPE_OCTAL; 1676 break; 1677 case 'p': 1678 flags |= ESCAPE_NP; 1679 break; 1680 case 's': 1681 flags |= ESCAPE_SPACE; 1682 break; 1683 default: 1684 found = false; 1685 break; 1686 } 1687 } while (found); 1688 1689 if (!flags) 1690 flags = ESCAPE_ANY_NP; 1691 1692 len = spec.field_width < 0 ? 1 : spec.field_width; 1693 1694 /* 1695 * string_escape_mem() writes as many characters as it can to 1696 * the given buffer, and returns the total size of the output 1697 * had the buffer been big enough. 1698 */ 1699 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1700 1701 return buf; 1702 } 1703 1704 __diag_push(); 1705 __diag_ignore(GCC, all, "-Wsuggest-attribute=format", 1706 "Not a valid __printf() conversion candidate."); 1707 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1708 struct printf_spec spec) 1709 { 1710 va_list va; 1711 1712 if (check_pointer(&buf, end, va_fmt, spec)) 1713 return buf; 1714 1715 va_copy(va, *va_fmt->va); 1716 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1717 va_end(va); 1718 1719 return buf; 1720 } 1721 __diag_pop(); 1722 1723 static noinline_for_stack 1724 char *uuid_string(char *buf, char *end, const u8 *addr, 1725 struct printf_spec spec, const char *fmt) 1726 { 1727 char uuid[UUID_STRING_LEN + 1]; 1728 char *p = uuid; 1729 int i; 1730 const u8 *index = uuid_index; 1731 bool uc = false; 1732 1733 if (check_pointer(&buf, end, addr, spec)) 1734 return buf; 1735 1736 switch (*(++fmt)) { 1737 case 'L': 1738 uc = true; 1739 fallthrough; 1740 case 'l': 1741 index = guid_index; 1742 break; 1743 case 'B': 1744 uc = true; 1745 break; 1746 } 1747 1748 for (i = 0; i < 16; i++) { 1749 if (uc) 1750 p = hex_byte_pack_upper(p, addr[index[i]]); 1751 else 1752 p = hex_byte_pack(p, addr[index[i]]); 1753 switch (i) { 1754 case 3: 1755 case 5: 1756 case 7: 1757 case 9: 1758 *p++ = '-'; 1759 break; 1760 } 1761 } 1762 1763 *p = 0; 1764 1765 return string_nocheck(buf, end, uuid, spec); 1766 } 1767 1768 static noinline_for_stack 1769 char *netdev_bits(char *buf, char *end, const void *addr, 1770 struct printf_spec spec, const char *fmt) 1771 { 1772 unsigned long long num; 1773 int size; 1774 1775 if (check_pointer(&buf, end, addr, spec)) 1776 return buf; 1777 1778 switch (fmt[1]) { 1779 case 'F': 1780 num = *(const netdev_features_t *)addr; 1781 size = sizeof(netdev_features_t); 1782 break; 1783 default: 1784 return error_string(buf, end, "(%pN?)", spec); 1785 } 1786 1787 return special_hex_number(buf, end, num, size); 1788 } 1789 1790 static noinline_for_stack 1791 char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1792 struct printf_spec spec, const char *fmt) 1793 { 1794 char output[sizeof("0123 little-endian (0x01234567)")]; 1795 char *p = output; 1796 unsigned int i; 1797 bool pixel_fmt = false; 1798 u32 orig, val; 1799 1800 if (fmt[1] != 'c') 1801 return error_string(buf, end, "(%p4?)", spec); 1802 1803 if (check_pointer(&buf, end, fourcc, spec)) 1804 return buf; 1805 1806 orig = get_unaligned(fourcc); 1807 switch (fmt[2]) { 1808 case 'h': 1809 if (fmt[3] == 'R') 1810 orig = swab32(orig); 1811 break; 1812 case 'l': 1813 orig = (__force u32)cpu_to_le32(orig); 1814 break; 1815 case 'b': 1816 orig = (__force u32)cpu_to_be32(orig); 1817 break; 1818 case 'c': 1819 /* Pixel formats are printed LSB-first */ 1820 pixel_fmt = true; 1821 break; 1822 default: 1823 return error_string(buf, end, "(%p4?)", spec); 1824 } 1825 1826 val = pixel_fmt ? swab32(orig & ~BIT(31)) : orig; 1827 1828 for (i = 0; i < sizeof(u32); i++) { 1829 unsigned char c = val >> ((3 - i) * 8); 1830 1831 /* Print non-control ASCII characters as-is, dot otherwise */ 1832 *p++ = isascii(c) && isprint(c) ? c : '.'; 1833 } 1834 1835 if (pixel_fmt) { 1836 *p++ = ' '; 1837 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1838 p += strlen(p); 1839 } 1840 1841 *p++ = ' '; 1842 *p++ = '('; 1843 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1844 *p++ = ')'; 1845 *p = '\0'; 1846 1847 return string(buf, end, output, spec); 1848 } 1849 1850 static noinline_for_stack 1851 char *address_val(char *buf, char *end, const void *addr, 1852 struct printf_spec spec, const char *fmt) 1853 { 1854 unsigned long long num; 1855 int size; 1856 1857 if (check_pointer(&buf, end, addr, spec)) 1858 return buf; 1859 1860 switch (fmt[1]) { 1861 case 'd': 1862 num = *(const dma_addr_t *)addr; 1863 size = sizeof(dma_addr_t); 1864 break; 1865 case 'p': 1866 default: 1867 num = *(const phys_addr_t *)addr; 1868 size = sizeof(phys_addr_t); 1869 break; 1870 } 1871 1872 return special_hex_number(buf, end, num, size); 1873 } 1874 1875 static noinline_for_stack 1876 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1877 { 1878 int year = tm->tm_year + (r ? 0 : 1900); 1879 int mon = tm->tm_mon + (r ? 0 : 1); 1880 1881 buf = number(buf, end, year, default_dec04_spec); 1882 if (buf < end) 1883 *buf = '-'; 1884 buf++; 1885 1886 buf = number(buf, end, mon, default_dec02_spec); 1887 if (buf < end) 1888 *buf = '-'; 1889 buf++; 1890 1891 return number(buf, end, tm->tm_mday, default_dec02_spec); 1892 } 1893 1894 static noinline_for_stack 1895 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1896 { 1897 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1898 if (buf < end) 1899 *buf = ':'; 1900 buf++; 1901 1902 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1903 if (buf < end) 1904 *buf = ':'; 1905 buf++; 1906 1907 return number(buf, end, tm->tm_sec, default_dec02_spec); 1908 } 1909 1910 static noinline_for_stack 1911 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1912 struct printf_spec spec, const char *fmt) 1913 { 1914 bool have_t = true, have_d = true; 1915 bool raw = false, iso8601_separator = true; 1916 bool found = true; 1917 int count = 2; 1918 1919 switch (fmt[count]) { 1920 case 'd': 1921 have_t = false; 1922 count++; 1923 break; 1924 case 't': 1925 have_d = false; 1926 count++; 1927 break; 1928 } 1929 1930 do { 1931 switch (fmt[count++]) { 1932 case 'r': 1933 raw = true; 1934 break; 1935 case 's': 1936 iso8601_separator = false; 1937 break; 1938 default: 1939 found = false; 1940 break; 1941 } 1942 } while (found); 1943 1944 if (have_d) 1945 buf = date_str(buf, end, tm, raw); 1946 if (have_d && have_t) { 1947 if (buf < end) 1948 *buf = iso8601_separator ? 'T' : ' '; 1949 buf++; 1950 } 1951 if (have_t) 1952 buf = time_str(buf, end, tm, raw); 1953 1954 return buf; 1955 } 1956 1957 static noinline_for_stack 1958 char *time64_str(char *buf, char *end, const time64_t time, 1959 struct printf_spec spec, const char *fmt) 1960 { 1961 struct rtc_time rtc_time; 1962 struct tm tm; 1963 1964 time64_to_tm(time, 0, &tm); 1965 1966 rtc_time.tm_sec = tm.tm_sec; 1967 rtc_time.tm_min = tm.tm_min; 1968 rtc_time.tm_hour = tm.tm_hour; 1969 rtc_time.tm_mday = tm.tm_mday; 1970 rtc_time.tm_mon = tm.tm_mon; 1971 rtc_time.tm_year = tm.tm_year; 1972 rtc_time.tm_wday = tm.tm_wday; 1973 rtc_time.tm_yday = tm.tm_yday; 1974 1975 rtc_time.tm_isdst = 0; 1976 1977 return rtc_str(buf, end, &rtc_time, spec, fmt); 1978 } 1979 1980 static noinline_for_stack 1981 char *timespec64_str(char *buf, char *end, const struct timespec64 *ts, 1982 struct printf_spec spec, const char *fmt) 1983 { 1984 static const struct printf_spec default_dec09_spec = { 1985 .base = 10, 1986 .field_width = 9, 1987 .precision = -1, 1988 .flags = ZEROPAD, 1989 }; 1990 1991 if (fmt[2] == 'p') 1992 buf = number(buf, end, ts->tv_sec, default_dec_spec); 1993 else 1994 buf = time64_str(buf, end, ts->tv_sec, spec, fmt); 1995 if (buf < end) 1996 *buf = '.'; 1997 buf++; 1998 1999 return number(buf, end, ts->tv_nsec, default_dec09_spec); 2000 } 2001 2002 static noinline_for_stack 2003 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 2004 const char *fmt) 2005 { 2006 if (check_pointer(&buf, end, ptr, spec)) 2007 return buf; 2008 2009 switch (fmt[1]) { 2010 case 'R': 2011 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 2012 case 'S': 2013 return timespec64_str(buf, end, (const struct timespec64 *)ptr, spec, fmt); 2014 case 'T': 2015 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 2016 default: 2017 return error_string(buf, end, "(%pt?)", spec); 2018 } 2019 } 2020 2021 static noinline_for_stack 2022 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 2023 const char *fmt) 2024 { 2025 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 2026 return error_string(buf, end, "(%pC?)", spec); 2027 2028 if (check_pointer(&buf, end, clk, spec)) 2029 return buf; 2030 2031 #ifdef CONFIG_COMMON_CLK 2032 return string(buf, end, __clk_get_name(clk), spec); 2033 #else 2034 return ptr_to_id(buf, end, clk, spec); 2035 #endif 2036 } 2037 2038 static 2039 char *format_flags(char *buf, char *end, unsigned long flags, 2040 const struct trace_print_flags *names) 2041 { 2042 unsigned long mask; 2043 2044 for ( ; flags && names->name; names++) { 2045 mask = names->mask; 2046 if ((flags & mask) != mask) 2047 continue; 2048 2049 buf = string(buf, end, names->name, default_str_spec); 2050 2051 flags &= ~mask; 2052 if (flags) { 2053 if (buf < end) 2054 *buf = '|'; 2055 buf++; 2056 } 2057 } 2058 2059 if (flags) 2060 buf = number(buf, end, flags, default_flag_spec); 2061 2062 return buf; 2063 } 2064 2065 struct page_flags_fields { 2066 int width; 2067 int shift; 2068 int mask; 2069 const struct printf_spec *spec; 2070 const char *name; 2071 }; 2072 2073 static const struct page_flags_fields pff[] = { 2074 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 2075 &default_dec_spec, "section"}, 2076 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2077 &default_dec_spec, "node"}, 2078 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2079 &default_dec_spec, "zone"}, 2080 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2081 &default_flag_spec, "lastcpupid"}, 2082 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2083 &default_flag_spec, "kasantag"}, 2084 }; 2085 2086 static 2087 char *format_page_flags(char *buf, char *end, unsigned long flags) 2088 { 2089 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2090 bool append = false; 2091 int i; 2092 2093 buf = number(buf, end, flags, default_flag_spec); 2094 if (buf < end) 2095 *buf = '('; 2096 buf++; 2097 2098 /* Page flags from the main area. */ 2099 if (main_flags) { 2100 buf = format_flags(buf, end, main_flags, pageflag_names); 2101 append = true; 2102 } 2103 2104 /* Page flags from the fields area */ 2105 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2106 /* Skip undefined fields. */ 2107 if (!pff[i].width) 2108 continue; 2109 2110 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2111 if (append) { 2112 if (buf < end) 2113 *buf = '|'; 2114 buf++; 2115 } 2116 2117 buf = string(buf, end, pff[i].name, default_str_spec); 2118 if (buf < end) 2119 *buf = '='; 2120 buf++; 2121 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2122 *pff[i].spec); 2123 2124 append = true; 2125 } 2126 if (buf < end) 2127 *buf = ')'; 2128 buf++; 2129 2130 return buf; 2131 } 2132 2133 static noinline_for_stack 2134 char *flags_string(char *buf, char *end, void *flags_ptr, 2135 struct printf_spec spec, const char *fmt) 2136 { 2137 unsigned long flags; 2138 const struct trace_print_flags *names; 2139 2140 if (check_pointer(&buf, end, flags_ptr, spec)) 2141 return buf; 2142 2143 switch (fmt[1]) { 2144 case 'p': 2145 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2146 case 'v': 2147 flags = *(unsigned long *)flags_ptr; 2148 names = vmaflag_names; 2149 break; 2150 case 'g': 2151 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2152 names = gfpflag_names; 2153 break; 2154 default: 2155 return error_string(buf, end, "(%pG?)", spec); 2156 } 2157 2158 return format_flags(buf, end, flags, names); 2159 } 2160 2161 static noinline_for_stack 2162 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2163 char *end) 2164 { 2165 int depth; 2166 2167 /* Loop starting from the root node to the current node. */ 2168 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2169 /* 2170 * Only get a reference for other nodes (i.e. parent nodes). 2171 * fwnode refcount may be 0 here. 2172 */ 2173 struct fwnode_handle *__fwnode = depth ? 2174 fwnode_get_nth_parent(fwnode, depth) : fwnode; 2175 2176 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2177 default_str_spec); 2178 buf = string(buf, end, fwnode_get_name(__fwnode), 2179 default_str_spec); 2180 2181 if (depth) 2182 fwnode_handle_put(__fwnode); 2183 } 2184 2185 return buf; 2186 } 2187 2188 static noinline_for_stack 2189 char *device_node_string(char *buf, char *end, struct device_node *dn, 2190 struct printf_spec spec, const char *fmt) 2191 { 2192 char tbuf[sizeof("xxxx") + 1]; 2193 const char *p; 2194 int ret; 2195 char *buf_start = buf; 2196 struct property *prop; 2197 bool has_mult, pass; 2198 2199 struct printf_spec str_spec = spec; 2200 str_spec.field_width = -1; 2201 2202 if (fmt[0] != 'F') 2203 return error_string(buf, end, "(%pO?)", spec); 2204 2205 if (!IS_ENABLED(CONFIG_OF)) 2206 return error_string(buf, end, "(%pOF?)", spec); 2207 2208 if (check_pointer(&buf, end, dn, spec)) 2209 return buf; 2210 2211 /* simple case without anything any more format specifiers */ 2212 fmt++; 2213 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2214 fmt = "f"; 2215 2216 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2217 int precision; 2218 if (pass) { 2219 if (buf < end) 2220 *buf = ':'; 2221 buf++; 2222 } 2223 2224 switch (*fmt) { 2225 case 'f': /* full_name */ 2226 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2227 end); 2228 break; 2229 case 'n': /* name */ 2230 p = fwnode_get_name(of_fwnode_handle(dn)); 2231 precision = str_spec.precision; 2232 str_spec.precision = strchrnul(p, '@') - p; 2233 buf = string(buf, end, p, str_spec); 2234 str_spec.precision = precision; 2235 break; 2236 case 'p': /* phandle */ 2237 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2238 break; 2239 case 'P': /* path-spec */ 2240 p = fwnode_get_name(of_fwnode_handle(dn)); 2241 if (!p[1]) 2242 p = "/"; 2243 buf = string(buf, end, p, str_spec); 2244 break; 2245 case 'F': /* flags */ 2246 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2247 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2248 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2249 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2250 tbuf[4] = 0; 2251 buf = string_nocheck(buf, end, tbuf, str_spec); 2252 break; 2253 case 'c': /* major compatible string */ 2254 ret = of_property_read_string(dn, "compatible", &p); 2255 if (!ret) 2256 buf = string(buf, end, p, str_spec); 2257 break; 2258 case 'C': /* full compatible string */ 2259 has_mult = false; 2260 of_property_for_each_string(dn, "compatible", prop, p) { 2261 if (has_mult) 2262 buf = string_nocheck(buf, end, ",", str_spec); 2263 buf = string_nocheck(buf, end, "\"", str_spec); 2264 buf = string(buf, end, p, str_spec); 2265 buf = string_nocheck(buf, end, "\"", str_spec); 2266 2267 has_mult = true; 2268 } 2269 break; 2270 default: 2271 break; 2272 } 2273 } 2274 2275 return widen_string(buf, buf - buf_start, end, spec); 2276 } 2277 2278 static noinline_for_stack 2279 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2280 struct printf_spec spec, const char *fmt) 2281 { 2282 struct printf_spec str_spec = spec; 2283 char *buf_start = buf; 2284 2285 str_spec.field_width = -1; 2286 2287 if (*fmt != 'w') 2288 return error_string(buf, end, "(%pf?)", spec); 2289 2290 if (check_pointer(&buf, end, fwnode, spec)) 2291 return buf; 2292 2293 fmt++; 2294 2295 switch (*fmt) { 2296 case 'P': /* name */ 2297 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2298 break; 2299 case 'f': /* full_name */ 2300 default: 2301 buf = fwnode_full_name_string(fwnode, buf, end); 2302 break; 2303 } 2304 2305 return widen_string(buf, buf - buf_start, end, spec); 2306 } 2307 2308 static noinline_for_stack 2309 char *resource_or_range(const char *fmt, char *buf, char *end, void *ptr, 2310 struct printf_spec spec) 2311 { 2312 if (*fmt == 'r' && fmt[1] == 'a') 2313 return range_string(buf, end, ptr, spec, fmt); 2314 return resource_string(buf, end, ptr, spec, fmt); 2315 } 2316 2317 void __init hash_pointers_finalize(bool slub_debug) 2318 { 2319 switch (hash_pointers_mode) { 2320 case HASH_PTR_ALWAYS: 2321 no_hash_pointers = false; 2322 break; 2323 case HASH_PTR_NEVER: 2324 no_hash_pointers = true; 2325 break; 2326 case HASH_PTR_AUTO: 2327 default: 2328 no_hash_pointers = slub_debug; 2329 break; 2330 } 2331 2332 if (!no_hash_pointers) 2333 return; 2334 2335 pr_warn("**********************************************************\n"); 2336 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2337 pr_warn("** **\n"); 2338 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2339 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2340 pr_warn("** might reduce the security of your system. **\n"); 2341 pr_warn("** **\n"); 2342 pr_warn("** If you see this message and you are not debugging **\n"); 2343 pr_warn("** the kernel, report this immediately to your system **\n"); 2344 pr_warn("** administrator! **\n"); 2345 pr_warn("** **\n"); 2346 pr_warn("** Use hash_pointers=always to force this mode off **\n"); 2347 pr_warn("** **\n"); 2348 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2349 pr_warn("**********************************************************\n"); 2350 } 2351 2352 static int __init hash_pointers_mode_parse(char *str) 2353 { 2354 if (!str) { 2355 pr_warn("Hash pointers mode empty; falling back to auto.\n"); 2356 hash_pointers_mode = HASH_PTR_AUTO; 2357 } else if (strncmp(str, "auto", 4) == 0) { 2358 pr_info("Hash pointers mode set to auto.\n"); 2359 hash_pointers_mode = HASH_PTR_AUTO; 2360 } else if (strncmp(str, "never", 5) == 0) { 2361 pr_info("Hash pointers mode set to never.\n"); 2362 hash_pointers_mode = HASH_PTR_NEVER; 2363 } else if (strncmp(str, "always", 6) == 0) { 2364 pr_info("Hash pointers mode set to always.\n"); 2365 hash_pointers_mode = HASH_PTR_ALWAYS; 2366 } else { 2367 pr_warn("Unknown hash_pointers mode '%s' specified; assuming auto.\n", str); 2368 hash_pointers_mode = HASH_PTR_AUTO; 2369 } 2370 2371 return 0; 2372 } 2373 early_param("hash_pointers", hash_pointers_mode_parse); 2374 2375 static int __init no_hash_pointers_enable(char *str) 2376 { 2377 return hash_pointers_mode_parse("never"); 2378 } 2379 early_param("no_hash_pointers", no_hash_pointers_enable); 2380 2381 /* 2382 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2383 * by an extra set of alphanumeric characters that are extended format 2384 * specifiers. 2385 * 2386 * Please update scripts/checkpatch.pl when adding/removing conversion 2387 * characters. (Search for "check for vsprintf extension"). 2388 * 2389 * Right now we handle: 2390 * 2391 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2392 * - 's' For symbolic direct pointers (or function descriptors) without offset 2393 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2394 * - 'S[R]b' as above with module build ID (for use in backtraces) 2395 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2396 * %ps and %pS. Be careful when re-using these specifiers. 2397 * - 'B' For backtraced symbolic direct pointers with offset 2398 * - 'Bb' as above with module build ID (for use in backtraces) 2399 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2400 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2401 * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] 2402 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2403 * width which must be explicitly specified either as part of the 2404 * format string '%32b[l]' or through '%*b[l]', [l] selects 2405 * range-list format instead of hex format 2406 * - 'M' For a 6-byte MAC address, it prints the address in the 2407 * usual colon-separated hex notation 2408 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2409 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2410 * with a dash-separated hex notation 2411 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2412 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2413 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2414 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2415 * [S][pfs] 2416 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2417 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2418 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2419 * IPv6 omits the colons (01020304...0f) 2420 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2421 * [S][pfs] 2422 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2423 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2424 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2425 * - 'I[6S]c' for IPv6 addresses printed as specified by 2426 * https://tools.ietf.org/html/rfc5952 2427 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2428 * of the following flags (see string_escape_mem() for the 2429 * details): 2430 * a - ESCAPE_ANY 2431 * c - ESCAPE_SPECIAL 2432 * h - ESCAPE_HEX 2433 * n - ESCAPE_NULL 2434 * o - ESCAPE_OCTAL 2435 * p - ESCAPE_NP 2436 * s - ESCAPE_SPACE 2437 * By default ESCAPE_ANY_NP is used. 2438 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2439 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2440 * Options for %pU are: 2441 * b big endian lower case hex (default) 2442 * B big endian UPPER case hex 2443 * l little endian lower case hex 2444 * L little endian UPPER case hex 2445 * big endian output byte order is: 2446 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2447 * little endian output byte order is: 2448 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2449 * - 'V' For a struct va_format which contains a format string * and va_list *, 2450 * call vsnprintf(->format, *->va_list). 2451 * Implements a "recursive vsnprintf". 2452 * Do not use this feature without some mechanism to verify the 2453 * correctness of the format string and va_list arguments. 2454 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2455 * Use only for procfs, sysfs and similar files, not printk(); please 2456 * read the documentation (path below) first. 2457 * - 'NF' For a netdev_features_t 2458 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2459 * - '4c[h[R]lb]' For generic FourCC code with raw numerical value. Both are 2460 * displayed in the big-endian format. This is the opposite of V4L2 or 2461 * DRM FourCCs. 2462 * The additional specifiers define what endianness is used to load 2463 * the stored bytes. The data might be interpreted using the host, 2464 * reversed host byte order, little-endian, or big-endian. 2465 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2466 * a certain separator (' ' by default): 2467 * C colon 2468 * D dash 2469 * N no separator 2470 * The maximum supported length is 64 bytes of the input. Consider 2471 * to use print_hex_dump() for the larger input. 2472 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2473 * (default assumed to be phys_addr_t, passed by reference) 2474 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2475 * - 'D[234]' Same as 'd' but for a struct file 2476 * - 'g' For block_device name (gendisk + partition number) 2477 * - 't[RST][dt][r][s]' For time and date as represented by: 2478 * R struct rtc_time 2479 * S struct timespec64 2480 * T time64_t 2481 * - 'tSp' For time represented by struct timespec64 printed as <seconds>.<nanoseconds> 2482 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2483 * (legacy clock framework) of the clock 2484 * - 'G' For flags to be printed as a collection of symbolic strings that would 2485 * construct the specific value. Supported flags given by option: 2486 * p page flags (see struct page) given as pointer to unsigned long 2487 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2488 * v vma flags (VM_*) given as pointer to unsigned long 2489 * - 'OF[fnpPcCF]' For a device tree object 2490 * Without any optional arguments prints the full_name 2491 * f device node full_name 2492 * n device node name 2493 * p device node phandle 2494 * P device node path spec (name + @unit) 2495 * F device node flags 2496 * c major compatible string 2497 * C full compatible string 2498 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2499 * Without an option prints the full name of the node 2500 * f full name 2501 * P node name, including a possible unit address 2502 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2503 * Please read the documentation (path below) before using! 2504 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2505 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2506 * or user (u) memory to probe, and: 2507 * s a string, equivalent to "%s" on direct vsnprintf() use 2508 * 2509 * ** When making changes please also update: 2510 * Documentation/core-api/printk-formats.rst 2511 * 2512 * Note: The default behaviour (unadorned %p) is to hash the address, 2513 * rendering it useful as a unique identifier. 2514 * 2515 * There is also a '%pA' format specifier, but it is only intended to be used 2516 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2517 * See rust/kernel/print.rs for details. 2518 */ 2519 static noinline_for_stack 2520 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2521 struct printf_spec spec) 2522 { 2523 switch (*fmt) { 2524 case 'S': 2525 case 's': 2526 ptr = dereference_symbol_descriptor(ptr); 2527 fallthrough; 2528 case 'B': 2529 return symbol_string(buf, end, ptr, spec, fmt); 2530 case 'R': 2531 case 'r': 2532 return resource_or_range(fmt, buf, end, ptr, spec); 2533 case 'h': 2534 return hex_string(buf, end, ptr, spec, fmt); 2535 case 'b': 2536 switch (fmt[1]) { 2537 case 'l': 2538 return bitmap_list_string(buf, end, ptr, spec, fmt); 2539 default: 2540 return bitmap_string(buf, end, ptr, spec, fmt); 2541 } 2542 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2543 case 'm': /* Contiguous: 000102030405 */ 2544 /* [mM]F (FDDI) */ 2545 /* [mM]R (Reverse order; Bluetooth) */ 2546 return mac_address_string(buf, end, ptr, spec, fmt); 2547 case 'I': /* Formatted IP supported 2548 * 4: 1.2.3.4 2549 * 6: 0001:0203:...:0708 2550 * 6c: 1::708 or 1::1.2.3.4 2551 */ 2552 case 'i': /* Contiguous: 2553 * 4: 001.002.003.004 2554 * 6: 000102...0f 2555 */ 2556 return ip_addr_string(buf, end, ptr, spec, fmt); 2557 case 'E': 2558 return escaped_string(buf, end, ptr, spec, fmt); 2559 case 'U': 2560 return uuid_string(buf, end, ptr, spec, fmt); 2561 case 'V': 2562 return va_format(buf, end, ptr, spec); 2563 case 'K': 2564 return restricted_pointer(buf, end, ptr, spec); 2565 case 'N': 2566 return netdev_bits(buf, end, ptr, spec, fmt); 2567 case '4': 2568 return fourcc_string(buf, end, ptr, spec, fmt); 2569 case 'a': 2570 return address_val(buf, end, ptr, spec, fmt); 2571 case 'd': 2572 return dentry_name(buf, end, ptr, spec, fmt); 2573 case 't': 2574 return time_and_date(buf, end, ptr, spec, fmt); 2575 case 'C': 2576 return clock(buf, end, ptr, spec, fmt); 2577 case 'D': 2578 return file_dentry_name(buf, end, ptr, spec, fmt); 2579 #ifdef CONFIG_BLOCK 2580 case 'g': 2581 return bdev_name(buf, end, ptr, spec, fmt); 2582 #endif 2583 2584 case 'G': 2585 return flags_string(buf, end, ptr, spec, fmt); 2586 case 'O': 2587 return device_node_string(buf, end, ptr, spec, fmt + 1); 2588 case 'f': 2589 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2590 case 'A': 2591 if (!IS_ENABLED(CONFIG_RUST)) { 2592 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2593 return error_string(buf, end, "(%pA?)", spec); 2594 } 2595 return rust_fmt_argument(buf, end, ptr); 2596 case 'x': 2597 return pointer_string(buf, end, ptr, spec); 2598 case 'e': 2599 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2600 if (!IS_ERR(ptr)) 2601 return default_pointer(buf, end, ptr, spec); 2602 return err_ptr(buf, end, ptr, spec); 2603 case 'u': 2604 case 'k': 2605 switch (fmt[1]) { 2606 case 's': 2607 return string(buf, end, ptr, spec); 2608 default: 2609 return error_string(buf, end, "(einval)", spec); 2610 } 2611 default: 2612 return default_pointer(buf, end, ptr, spec); 2613 } 2614 } 2615 2616 struct fmt { 2617 const char *str; 2618 unsigned char state; // enum format_state 2619 unsigned char size; // size of numbers 2620 }; 2621 2622 #define SPEC_CHAR(x, flag) [(x)-32] = flag 2623 static unsigned char spec_flag(unsigned char c) 2624 { 2625 static const unsigned char spec_flag_array[] = { 2626 SPEC_CHAR(' ', SPACE), 2627 SPEC_CHAR('#', SPECIAL), 2628 SPEC_CHAR('+', PLUS), 2629 SPEC_CHAR('-', LEFT), 2630 SPEC_CHAR('0', ZEROPAD), 2631 }; 2632 c -= 32; 2633 return (c < sizeof(spec_flag_array)) ? spec_flag_array[c] : 0; 2634 } 2635 2636 /* 2637 * Helper function to decode printf style format. 2638 * Each call decode a token from the format and return the 2639 * number of characters read (or likely the delta where it wants 2640 * to go on the next call). 2641 * The decoded token is returned through the parameters 2642 * 2643 * 'h', 'l', or 'L' for integer fields 2644 * 'z' support added 23/7/1999 S.H. 2645 * 'z' changed to 'Z' --davidm 1/25/99 2646 * 'Z' changed to 'z' --adobriyan 2017-01-25 2647 * 't' added for ptrdiff_t 2648 * 2649 * @fmt: the format string 2650 * @type of the token returned 2651 * @flags: various flags such as +, -, # tokens.. 2652 * @field_width: overwritten width 2653 * @base: base of the number (octal, hex, ...) 2654 * @precision: precision of a number 2655 * @qualifier: qualifier of a number (long, size_t, ...) 2656 */ 2657 static noinline_for_stack 2658 struct fmt format_decode(struct fmt fmt, struct printf_spec *spec) 2659 { 2660 const char *start = fmt.str; 2661 char flag; 2662 2663 /* we finished early by reading the field width */ 2664 if (unlikely(fmt.state == FORMAT_STATE_WIDTH)) { 2665 if (spec->field_width < 0) { 2666 spec->field_width = -spec->field_width; 2667 spec->flags |= LEFT; 2668 } 2669 fmt.state = FORMAT_STATE_NONE; 2670 goto precision; 2671 } 2672 2673 /* we finished early by reading the precision */ 2674 if (unlikely(fmt.state == FORMAT_STATE_PRECISION)) { 2675 if (spec->precision < 0) 2676 spec->precision = 0; 2677 2678 fmt.state = FORMAT_STATE_NONE; 2679 goto qualifier; 2680 } 2681 2682 /* By default */ 2683 fmt.state = FORMAT_STATE_NONE; 2684 2685 for (; *fmt.str ; fmt.str++) { 2686 if (*fmt.str == '%') 2687 break; 2688 } 2689 2690 /* Return the current non-format string */ 2691 if (fmt.str != start || !*fmt.str) 2692 return fmt; 2693 2694 /* Process flags. This also skips the first '%' */ 2695 spec->flags = 0; 2696 do { 2697 /* this also skips first '%' */ 2698 flag = spec_flag(*++fmt.str); 2699 spec->flags |= flag; 2700 } while (flag); 2701 2702 /* get field width */ 2703 spec->field_width = -1; 2704 2705 if (isdigit(*fmt.str)) 2706 spec->field_width = skip_atoi(&fmt.str); 2707 else if (unlikely(*fmt.str == '*')) { 2708 /* it's the next argument */ 2709 fmt.state = FORMAT_STATE_WIDTH; 2710 fmt.str++; 2711 return fmt; 2712 } 2713 2714 precision: 2715 /* get the precision */ 2716 spec->precision = -1; 2717 if (unlikely(*fmt.str == '.')) { 2718 fmt.str++; 2719 if (isdigit(*fmt.str)) { 2720 spec->precision = skip_atoi(&fmt.str); 2721 if (spec->precision < 0) 2722 spec->precision = 0; 2723 } else if (*fmt.str == '*') { 2724 /* it's the next argument */ 2725 fmt.state = FORMAT_STATE_PRECISION; 2726 fmt.str++; 2727 return fmt; 2728 } 2729 } 2730 2731 qualifier: 2732 /* Set up default numeric format */ 2733 spec->base = 10; 2734 fmt.state = FORMAT_STATE_NUM; 2735 fmt.size = sizeof(int); 2736 static const struct format_state { 2737 unsigned char state; 2738 unsigned char size; 2739 unsigned char flags_or_double_size; 2740 unsigned char base; 2741 } lookup_state[256] = { 2742 // Length 2743 ['l'] = { 0, sizeof(long), sizeof(long long) }, 2744 ['L'] = { 0, sizeof(long long) }, 2745 ['h'] = { 0, sizeof(short), sizeof(char) }, 2746 ['H'] = { 0, sizeof(char) }, // Questionable historical 2747 ['z'] = { 0, sizeof(size_t) }, 2748 ['t'] = { 0, sizeof(ptrdiff_t) }, 2749 2750 // Non-numeric formats 2751 ['c'] = { FORMAT_STATE_CHAR }, 2752 ['s'] = { FORMAT_STATE_STR }, 2753 ['p'] = { FORMAT_STATE_PTR }, 2754 ['%'] = { FORMAT_STATE_PERCENT_CHAR }, 2755 2756 // Numerics 2757 ['o'] = { FORMAT_STATE_NUM, 0, 0, 8 }, 2758 ['x'] = { FORMAT_STATE_NUM, 0, SMALL, 16 }, 2759 ['X'] = { FORMAT_STATE_NUM, 0, 0, 16 }, 2760 ['d'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2761 ['i'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2762 ['u'] = { FORMAT_STATE_NUM, 0, 0, 10, }, 2763 2764 /* 2765 * Since %n poses a greater security risk than 2766 * utility, treat it as any other invalid or 2767 * unsupported format specifier. 2768 */ 2769 }; 2770 2771 const struct format_state *p = lookup_state + (u8)*fmt.str; 2772 if (p->size) { 2773 fmt.size = p->size; 2774 if (p->flags_or_double_size && fmt.str[0] == fmt.str[1]) { 2775 fmt.size = p->flags_or_double_size; 2776 fmt.str++; 2777 } 2778 fmt.str++; 2779 p = lookup_state + *fmt.str; 2780 } 2781 if (p->state) { 2782 if (p->base) 2783 spec->base = p->base; 2784 spec->flags |= p->flags_or_double_size; 2785 fmt.state = p->state; 2786 fmt.str++; 2787 return fmt; 2788 } 2789 2790 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt.str); 2791 fmt.state = FORMAT_STATE_INVALID; 2792 return fmt; 2793 } 2794 2795 static void 2796 set_field_width(struct printf_spec *spec, int width) 2797 { 2798 spec->field_width = width; 2799 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2800 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2801 } 2802 } 2803 2804 static void 2805 set_precision(struct printf_spec *spec, int prec) 2806 { 2807 spec->precision = prec; 2808 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2809 spec->precision = clamp(prec, 0, PRECISION_MAX); 2810 } 2811 } 2812 2813 /* 2814 * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate 2815 * as necessary and deal with signedness. 2816 * 2817 * 'size' is the size of the value in bytes. 2818 */ 2819 static unsigned long long convert_num_spec(unsigned int val, int size, struct printf_spec spec) 2820 { 2821 unsigned int shift = 32 - size*8; 2822 2823 val <<= shift; 2824 if (!(spec.flags & SIGN)) 2825 return val >> shift; 2826 return (int)val >> shift; 2827 } 2828 2829 /** 2830 * vsnprintf - Format a string and place it in a buffer 2831 * @buf: The buffer to place the result into 2832 * @size: The size of the buffer, including the trailing null space 2833 * @fmt_str: The format string to use 2834 * @args: Arguments for the format string 2835 * 2836 * This function generally follows C99 vsnprintf, but has some 2837 * extensions and a few limitations: 2838 * 2839 * - ``%n`` is unsupported 2840 * - ``%p*`` is handled by pointer() 2841 * 2842 * See pointer() or Documentation/core-api/printk-formats.rst for more 2843 * extensive description. 2844 * 2845 * **Please update the documentation in both places when making changes** 2846 * 2847 * The return value is the number of characters which would 2848 * be generated for the given input, excluding the trailing 2849 * '\0', as per ISO C99. If you want to have the exact 2850 * number of characters written into @buf as return value 2851 * (not including the trailing '\0'), use vscnprintf(). If the 2852 * return is greater than or equal to @size, the resulting 2853 * string is truncated. 2854 * 2855 * If you're not already dealing with a va_list consider using snprintf(). 2856 */ 2857 int vsnprintf(char *buf, size_t size, const char *fmt_str, va_list args) 2858 { 2859 char *str, *end; 2860 struct printf_spec spec = {0}; 2861 struct fmt fmt = { 2862 .str = fmt_str, 2863 .state = FORMAT_STATE_NONE, 2864 }; 2865 2866 /* Reject out-of-range values early. Large positive sizes are 2867 used for unknown buffer sizes. */ 2868 if (WARN_ON_ONCE(size > INT_MAX)) 2869 return 0; 2870 2871 str = buf; 2872 end = buf + size; 2873 2874 /* Make sure end is always >= buf */ 2875 if (end < buf) { 2876 end = ((void *)-1); 2877 size = end - buf; 2878 } 2879 2880 while (*fmt.str) { 2881 const char *old_fmt = fmt.str; 2882 2883 fmt = format_decode(fmt, &spec); 2884 2885 switch (fmt.state) { 2886 case FORMAT_STATE_NONE: { 2887 int read = fmt.str - old_fmt; 2888 if (str < end) { 2889 int copy = read; 2890 if (copy > end - str) 2891 copy = end - str; 2892 memcpy(str, old_fmt, copy); 2893 } 2894 str += read; 2895 continue; 2896 } 2897 2898 case FORMAT_STATE_NUM: { 2899 unsigned long long num; 2900 2901 if (fmt.size > sizeof(int)) 2902 num = va_arg(args, long long); 2903 else 2904 num = convert_num_spec(va_arg(args, int), fmt.size, spec); 2905 str = number(str, end, num, spec); 2906 continue; 2907 } 2908 2909 case FORMAT_STATE_WIDTH: 2910 set_field_width(&spec, va_arg(args, int)); 2911 continue; 2912 2913 case FORMAT_STATE_PRECISION: 2914 set_precision(&spec, va_arg(args, int)); 2915 continue; 2916 2917 case FORMAT_STATE_CHAR: { 2918 char c; 2919 2920 if (!(spec.flags & LEFT)) { 2921 while (--spec.field_width > 0) { 2922 if (str < end) 2923 *str = ' '; 2924 ++str; 2925 2926 } 2927 } 2928 c = (unsigned char) va_arg(args, int); 2929 if (str < end) 2930 *str = c; 2931 ++str; 2932 while (--spec.field_width > 0) { 2933 if (str < end) 2934 *str = ' '; 2935 ++str; 2936 } 2937 continue; 2938 } 2939 2940 case FORMAT_STATE_STR: 2941 str = string(str, end, va_arg(args, char *), spec); 2942 continue; 2943 2944 case FORMAT_STATE_PTR: 2945 str = pointer(fmt.str, str, end, va_arg(args, void *), 2946 spec); 2947 while (isalnum(*fmt.str)) 2948 fmt.str++; 2949 continue; 2950 2951 case FORMAT_STATE_PERCENT_CHAR: 2952 if (str < end) 2953 *str = '%'; 2954 ++str; 2955 continue; 2956 2957 default: 2958 /* 2959 * Presumably the arguments passed gcc's type 2960 * checking, but there is no safe or sane way 2961 * for us to continue parsing the format and 2962 * fetching from the va_list; the remaining 2963 * specifiers and arguments would be out of 2964 * sync. 2965 */ 2966 goto out; 2967 } 2968 } 2969 2970 out: 2971 if (size > 0) { 2972 if (str < end) 2973 *str = '\0'; 2974 else 2975 end[-1] = '\0'; 2976 } 2977 2978 /* the trailing null byte doesn't count towards the total */ 2979 return str-buf; 2980 2981 } 2982 EXPORT_SYMBOL(vsnprintf); 2983 2984 /** 2985 * vscnprintf - Format a string and place it in a buffer 2986 * @buf: The buffer to place the result into 2987 * @size: The size of the buffer, including the trailing null space 2988 * @fmt: The format string to use 2989 * @args: Arguments for the format string 2990 * 2991 * The return value is the number of characters which have been written into 2992 * the @buf not including the trailing '\0'. If @size is == 0 the function 2993 * returns 0. 2994 * 2995 * If you're not already dealing with a va_list consider using scnprintf(). 2996 * 2997 * See the vsnprintf() documentation for format string extensions over C99. 2998 */ 2999 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 3000 { 3001 int i; 3002 3003 if (unlikely(!size)) 3004 return 0; 3005 3006 i = vsnprintf(buf, size, fmt, args); 3007 3008 if (likely(i < size)) 3009 return i; 3010 3011 return size - 1; 3012 } 3013 EXPORT_SYMBOL(vscnprintf); 3014 3015 /** 3016 * snprintf - Format a string and place it in a buffer 3017 * @buf: The buffer to place the result into 3018 * @size: The size of the buffer, including the trailing null space 3019 * @fmt: The format string to use 3020 * @...: Arguments for the format string 3021 * 3022 * The return value is the number of characters which would be 3023 * generated for the given input, excluding the trailing null, 3024 * as per ISO C99. If the return is greater than or equal to 3025 * @size, the resulting string is truncated. 3026 * 3027 * See the vsnprintf() documentation for format string extensions over C99. 3028 */ 3029 int snprintf(char *buf, size_t size, const char *fmt, ...) 3030 { 3031 va_list args; 3032 int i; 3033 3034 va_start(args, fmt); 3035 i = vsnprintf(buf, size, fmt, args); 3036 va_end(args); 3037 3038 return i; 3039 } 3040 EXPORT_SYMBOL(snprintf); 3041 3042 /** 3043 * scnprintf - Format a string and place it in a buffer 3044 * @buf: The buffer to place the result into 3045 * @size: The size of the buffer, including the trailing null space 3046 * @fmt: The format string to use 3047 * @...: Arguments for the format string 3048 * 3049 * The return value is the number of characters written into @buf not including 3050 * the trailing '\0'. If @size is == 0 the function returns 0. 3051 */ 3052 3053 int scnprintf(char *buf, size_t size, const char *fmt, ...) 3054 { 3055 va_list args; 3056 int i; 3057 3058 va_start(args, fmt); 3059 i = vscnprintf(buf, size, fmt, args); 3060 va_end(args); 3061 3062 return i; 3063 } 3064 EXPORT_SYMBOL(scnprintf); 3065 3066 /** 3067 * vsprintf - Format a string and place it in a buffer 3068 * @buf: The buffer to place the result into 3069 * @fmt: The format string to use 3070 * @args: Arguments for the format string 3071 * 3072 * The return value is the number of characters written into @buf not including 3073 * the trailing '\0'. Use vsnprintf() or vscnprintf() in order to avoid 3074 * buffer overflows. 3075 * 3076 * If you're not already dealing with a va_list consider using sprintf(). 3077 * 3078 * See the vsnprintf() documentation for format string extensions over C99. 3079 */ 3080 int vsprintf(char *buf, const char *fmt, va_list args) 3081 { 3082 return vsnprintf(buf, INT_MAX, fmt, args); 3083 } 3084 EXPORT_SYMBOL(vsprintf); 3085 3086 /** 3087 * sprintf - Format a string and place it in a buffer 3088 * @buf: The buffer to place the result into 3089 * @fmt: The format string to use 3090 * @...: Arguments for the format string 3091 * 3092 * The return value is the number of characters written into @buf not including 3093 * the trailing '\0'. Use snprintf() or scnprintf() in order to avoid 3094 * buffer overflows. 3095 * 3096 * See the vsnprintf() documentation for format string extensions over C99. 3097 */ 3098 int sprintf(char *buf, const char *fmt, ...) 3099 { 3100 va_list args; 3101 int i; 3102 3103 va_start(args, fmt); 3104 i = vsnprintf(buf, INT_MAX, fmt, args); 3105 va_end(args); 3106 3107 return i; 3108 } 3109 EXPORT_SYMBOL(sprintf); 3110 3111 #ifdef CONFIG_BINARY_PRINTF 3112 /* 3113 * bprintf service: 3114 * vbin_printf() - VA arguments to binary data 3115 * bstr_printf() - Binary data to text string 3116 */ 3117 3118 /** 3119 * vbin_printf - Parse a format string and place args' binary value in a buffer 3120 * @bin_buf: The buffer to place args' binary value 3121 * @size: The size of the buffer(by words(32bits), not characters) 3122 * @fmt_str: The format string to use 3123 * @args: Arguments for the format string 3124 * 3125 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3126 * is skipped. 3127 * 3128 * The return value is the number of words(32bits) which would be generated for 3129 * the given input. 3130 * 3131 * NOTE: 3132 * If the return value is greater than @size, the resulting bin_buf is NOT 3133 * valid for bstr_printf(). 3134 */ 3135 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt_str, va_list args) 3136 { 3137 struct fmt fmt = { 3138 .str = fmt_str, 3139 .state = FORMAT_STATE_NONE, 3140 }; 3141 struct printf_spec spec = {0}; 3142 char *str, *end; 3143 int width; 3144 3145 str = (char *)bin_buf; 3146 end = (char *)(bin_buf + size); 3147 3148 #define save_arg(type) \ 3149 ({ \ 3150 unsigned long long value; \ 3151 if (sizeof(type) == 8) { \ 3152 unsigned long long val8; \ 3153 str = PTR_ALIGN(str, sizeof(u32)); \ 3154 val8 = va_arg(args, unsigned long long); \ 3155 if (str + sizeof(type) <= end) { \ 3156 *(u32 *)str = *(u32 *)&val8; \ 3157 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3158 } \ 3159 value = val8; \ 3160 } else { \ 3161 unsigned int val4; \ 3162 str = PTR_ALIGN(str, sizeof(type)); \ 3163 val4 = va_arg(args, int); \ 3164 if (str + sizeof(type) <= end) \ 3165 *(typeof(type) *)str = (type)(long)val4; \ 3166 value = (unsigned long long)val4; \ 3167 } \ 3168 str += sizeof(type); \ 3169 value; \ 3170 }) 3171 3172 while (*fmt.str) { 3173 fmt = format_decode(fmt, &spec); 3174 3175 switch (fmt.state) { 3176 case FORMAT_STATE_NONE: 3177 case FORMAT_STATE_PERCENT_CHAR: 3178 break; 3179 case FORMAT_STATE_INVALID: 3180 goto out; 3181 3182 case FORMAT_STATE_WIDTH: 3183 case FORMAT_STATE_PRECISION: 3184 width = (int)save_arg(int); 3185 /* Pointers may require the width */ 3186 if (*fmt.str == 'p') 3187 set_field_width(&spec, width); 3188 break; 3189 3190 case FORMAT_STATE_CHAR: 3191 save_arg(char); 3192 break; 3193 3194 case FORMAT_STATE_STR: { 3195 const char *save_str = va_arg(args, char *); 3196 const char *err_msg; 3197 size_t len; 3198 3199 err_msg = check_pointer_msg(save_str); 3200 if (err_msg) 3201 save_str = err_msg; 3202 3203 len = strlen(save_str) + 1; 3204 if (str + len < end) 3205 memcpy(str, save_str, len); 3206 str += len; 3207 break; 3208 } 3209 3210 case FORMAT_STATE_PTR: 3211 /* Dereferenced pointers must be done now */ 3212 switch (*fmt.str) { 3213 /* Dereference of functions is still OK */ 3214 case 'S': 3215 case 's': 3216 case 'x': 3217 case 'K': 3218 case 'e': 3219 save_arg(void *); 3220 break; 3221 default: 3222 if (!isalnum(*fmt.str)) { 3223 save_arg(void *); 3224 break; 3225 } 3226 str = pointer(fmt.str, str, end, va_arg(args, void *), 3227 spec); 3228 if (str + 1 < end) 3229 *str++ = '\0'; 3230 else 3231 end[-1] = '\0'; /* Must be nul terminated */ 3232 } 3233 /* skip all alphanumeric pointer suffixes */ 3234 while (isalnum(*fmt.str)) 3235 fmt.str++; 3236 break; 3237 3238 case FORMAT_STATE_NUM: 3239 if (fmt.size > sizeof(int)) { 3240 save_arg(long long); 3241 } else { 3242 save_arg(int); 3243 } 3244 } 3245 } 3246 3247 out: 3248 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3249 #undef save_arg 3250 } 3251 EXPORT_SYMBOL_GPL(vbin_printf); 3252 3253 /** 3254 * bstr_printf - Format a string from binary arguments and place it in a buffer 3255 * @buf: The buffer to place the result into 3256 * @size: The size of the buffer, including the trailing null space 3257 * @fmt_str: The format string to use 3258 * @bin_buf: Binary arguments for the format string 3259 * 3260 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3261 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3262 * a binary buffer that generated by vbin_printf. 3263 * 3264 * The format follows C99 vsnprintf, but has some extensions: 3265 * see vsnprintf comment for details. 3266 * 3267 * The return value is the number of characters which would 3268 * be generated for the given input, excluding the trailing 3269 * '\0', as per ISO C99. If you want to have the exact 3270 * number of characters written into @buf as return value 3271 * (not including the trailing '\0'), use vscnprintf(). If the 3272 * return is greater than or equal to @size, the resulting 3273 * string is truncated. 3274 */ 3275 int bstr_printf(char *buf, size_t size, const char *fmt_str, const u32 *bin_buf) 3276 { 3277 struct fmt fmt = { 3278 .str = fmt_str, 3279 .state = FORMAT_STATE_NONE, 3280 }; 3281 struct printf_spec spec = {0}; 3282 char *str, *end; 3283 const char *args = (const char *)bin_buf; 3284 3285 if (WARN_ON_ONCE(size > INT_MAX)) 3286 return 0; 3287 3288 str = buf; 3289 end = buf + size; 3290 3291 #define get_arg(type) \ 3292 ({ \ 3293 typeof(type) value; \ 3294 if (sizeof(type) == 8) { \ 3295 args = PTR_ALIGN(args, sizeof(u32)); \ 3296 *(u32 *)&value = *(u32 *)args; \ 3297 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3298 } else { \ 3299 args = PTR_ALIGN(args, sizeof(type)); \ 3300 value = *(typeof(type) *)args; \ 3301 } \ 3302 args += sizeof(type); \ 3303 value; \ 3304 }) 3305 3306 /* Make sure end is always >= buf */ 3307 if (end < buf) { 3308 end = ((void *)-1); 3309 size = end - buf; 3310 } 3311 3312 while (*fmt.str) { 3313 const char *old_fmt = fmt.str; 3314 unsigned long long num; 3315 3316 fmt = format_decode(fmt, &spec); 3317 switch (fmt.state) { 3318 case FORMAT_STATE_NONE: { 3319 int read = fmt.str - old_fmt; 3320 if (str < end) { 3321 int copy = read; 3322 if (copy > end - str) 3323 copy = end - str; 3324 memcpy(str, old_fmt, copy); 3325 } 3326 str += read; 3327 continue; 3328 } 3329 3330 case FORMAT_STATE_WIDTH: 3331 set_field_width(&spec, get_arg(int)); 3332 continue; 3333 3334 case FORMAT_STATE_PRECISION: 3335 set_precision(&spec, get_arg(int)); 3336 continue; 3337 3338 case FORMAT_STATE_CHAR: { 3339 char c; 3340 3341 if (!(spec.flags & LEFT)) { 3342 while (--spec.field_width > 0) { 3343 if (str < end) 3344 *str = ' '; 3345 ++str; 3346 } 3347 } 3348 c = (unsigned char) get_arg(char); 3349 if (str < end) 3350 *str = c; 3351 ++str; 3352 while (--spec.field_width > 0) { 3353 if (str < end) 3354 *str = ' '; 3355 ++str; 3356 } 3357 continue; 3358 } 3359 3360 case FORMAT_STATE_STR: { 3361 const char *str_arg = args; 3362 args += strlen(str_arg) + 1; 3363 str = string(str, end, (char *)str_arg, spec); 3364 continue; 3365 } 3366 3367 case FORMAT_STATE_PTR: { 3368 bool process = false; 3369 int copy, len; 3370 /* Non function dereferences were already done */ 3371 switch (*fmt.str) { 3372 case 'S': 3373 case 's': 3374 case 'x': 3375 case 'K': 3376 case 'e': 3377 process = true; 3378 break; 3379 default: 3380 if (!isalnum(*fmt.str)) { 3381 process = true; 3382 break; 3383 } 3384 /* Pointer dereference was already processed */ 3385 if (str < end) { 3386 len = copy = strlen(args); 3387 if (copy > end - str) 3388 copy = end - str; 3389 memcpy(str, args, copy); 3390 str += len; 3391 args += len + 1; 3392 } 3393 } 3394 if (process) 3395 str = pointer(fmt.str, str, end, get_arg(void *), spec); 3396 3397 while (isalnum(*fmt.str)) 3398 fmt.str++; 3399 continue; 3400 } 3401 3402 case FORMAT_STATE_PERCENT_CHAR: 3403 if (str < end) 3404 *str = '%'; 3405 ++str; 3406 continue; 3407 3408 case FORMAT_STATE_INVALID: 3409 goto out; 3410 3411 case FORMAT_STATE_NUM: 3412 if (fmt.size > sizeof(int)) 3413 num = get_arg(long long); 3414 else 3415 num = convert_num_spec(get_arg(int), fmt.size, spec); 3416 str = number(str, end, num, spec); 3417 continue; 3418 } 3419 } /* while(*fmt.str) */ 3420 3421 out: 3422 if (size > 0) { 3423 if (str < end) 3424 *str = '\0'; 3425 else 3426 end[-1] = '\0'; 3427 } 3428 3429 #undef get_arg 3430 3431 /* the trailing null byte doesn't count towards the total */ 3432 return str - buf; 3433 } 3434 EXPORT_SYMBOL_GPL(bstr_printf); 3435 3436 #endif /* CONFIG_BINARY_PRINTF */ 3437 3438 /** 3439 * vsscanf - Unformat a buffer into a list of arguments 3440 * @buf: input buffer 3441 * @fmt: format of buffer 3442 * @args: arguments 3443 */ 3444 int vsscanf(const char *buf, const char *fmt, va_list args) 3445 { 3446 const char *str = buf; 3447 char *next; 3448 char digit; 3449 int num = 0; 3450 u8 qualifier; 3451 unsigned int base; 3452 union { 3453 long long s; 3454 unsigned long long u; 3455 } val; 3456 s16 field_width; 3457 bool is_sign; 3458 3459 while (*fmt) { 3460 /* skip any white space in format */ 3461 /* white space in format matches any amount of 3462 * white space, including none, in the input. 3463 */ 3464 if (isspace(*fmt)) { 3465 fmt = skip_spaces(++fmt); 3466 str = skip_spaces(str); 3467 } 3468 3469 /* anything that is not a conversion must match exactly */ 3470 if (*fmt != '%' && *fmt) { 3471 if (*fmt++ != *str++) 3472 break; 3473 continue; 3474 } 3475 3476 if (!*fmt) 3477 break; 3478 ++fmt; 3479 3480 /* skip this conversion. 3481 * advance both strings to next white space 3482 */ 3483 if (*fmt == '*') { 3484 if (!*str) 3485 break; 3486 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3487 /* '%*[' not yet supported, invalid format */ 3488 if (*fmt == '[') 3489 return num; 3490 fmt++; 3491 } 3492 while (!isspace(*str) && *str) 3493 str++; 3494 continue; 3495 } 3496 3497 /* get field width */ 3498 field_width = -1; 3499 if (isdigit(*fmt)) { 3500 field_width = skip_atoi(&fmt); 3501 if (field_width <= 0) 3502 break; 3503 } 3504 3505 /* get conversion qualifier */ 3506 qualifier = -1; 3507 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3508 *fmt == 'z') { 3509 qualifier = *fmt++; 3510 if (unlikely(qualifier == *fmt)) { 3511 if (qualifier == 'h') { 3512 qualifier = 'H'; 3513 fmt++; 3514 } else if (qualifier == 'l') { 3515 qualifier = 'L'; 3516 fmt++; 3517 } 3518 } 3519 } 3520 3521 if (!*fmt) 3522 break; 3523 3524 if (*fmt == 'n') { 3525 /* return number of characters read so far */ 3526 *va_arg(args, int *) = str - buf; 3527 ++fmt; 3528 continue; 3529 } 3530 3531 if (!*str) 3532 break; 3533 3534 base = 10; 3535 is_sign = false; 3536 3537 switch (*fmt++) { 3538 case 'c': 3539 { 3540 char *s = (char *)va_arg(args, char*); 3541 if (field_width == -1) 3542 field_width = 1; 3543 do { 3544 *s++ = *str++; 3545 } while (--field_width > 0 && *str); 3546 num++; 3547 } 3548 continue; 3549 case 's': 3550 { 3551 char *s = (char *)va_arg(args, char *); 3552 if (field_width == -1) 3553 field_width = SHRT_MAX; 3554 /* first, skip leading white space in buffer */ 3555 str = skip_spaces(str); 3556 3557 /* now copy until next white space */ 3558 while (*str && !isspace(*str) && field_width--) 3559 *s++ = *str++; 3560 *s = '\0'; 3561 num++; 3562 } 3563 continue; 3564 /* 3565 * Warning: This implementation of the '[' conversion specifier 3566 * deviates from its glibc counterpart in the following ways: 3567 * (1) It does NOT support ranges i.e. '-' is NOT a special 3568 * character 3569 * (2) It cannot match the closing bracket ']' itself 3570 * (3) A field width is required 3571 * (4) '%*[' (discard matching input) is currently not supported 3572 * 3573 * Example usage: 3574 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3575 * buf1, buf2, buf3); 3576 * if (ret < 3) 3577 * // etc.. 3578 */ 3579 case '[': 3580 { 3581 char *s = (char *)va_arg(args, char *); 3582 DECLARE_BITMAP(set, 256) = {0}; 3583 unsigned int len = 0; 3584 bool negate = (*fmt == '^'); 3585 3586 /* field width is required */ 3587 if (field_width == -1) 3588 return num; 3589 3590 if (negate) 3591 ++fmt; 3592 3593 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3594 __set_bit((u8)*fmt, set); 3595 3596 /* no ']' or no character set found */ 3597 if (!*fmt || !len) 3598 return num; 3599 ++fmt; 3600 3601 if (negate) { 3602 bitmap_complement(set, set, 256); 3603 /* exclude null '\0' byte */ 3604 __clear_bit(0, set); 3605 } 3606 3607 /* match must be non-empty */ 3608 if (!test_bit((u8)*str, set)) 3609 return num; 3610 3611 while (test_bit((u8)*str, set) && field_width--) 3612 *s++ = *str++; 3613 *s = '\0'; 3614 ++num; 3615 } 3616 continue; 3617 case 'o': 3618 base = 8; 3619 break; 3620 case 'x': 3621 case 'X': 3622 base = 16; 3623 break; 3624 case 'i': 3625 base = 0; 3626 fallthrough; 3627 case 'd': 3628 is_sign = true; 3629 fallthrough; 3630 case 'u': 3631 break; 3632 case '%': 3633 /* looking for '%' in str */ 3634 if (*str++ != '%') 3635 return num; 3636 continue; 3637 default: 3638 /* invalid format; stop here */ 3639 return num; 3640 } 3641 3642 /* have some sort of integer conversion. 3643 * first, skip white space in buffer. 3644 */ 3645 str = skip_spaces(str); 3646 3647 digit = *str; 3648 if (is_sign && digit == '-') { 3649 if (field_width == 1) 3650 break; 3651 3652 digit = *(str + 1); 3653 } 3654 3655 if (!digit 3656 || (base == 16 && !isxdigit(digit)) 3657 || (base == 10 && !isdigit(digit)) 3658 || (base == 8 && !isodigit(digit)) 3659 || (base == 0 && !isdigit(digit))) 3660 break; 3661 3662 if (is_sign) 3663 val.s = simple_strntoll(str, &next, base, 3664 field_width >= 0 ? field_width : INT_MAX); 3665 else 3666 val.u = simple_strntoull(str, &next, base, 3667 field_width >= 0 ? field_width : INT_MAX); 3668 3669 switch (qualifier) { 3670 case 'H': /* that's 'hh' in format */ 3671 if (is_sign) 3672 *va_arg(args, signed char *) = val.s; 3673 else 3674 *va_arg(args, unsigned char *) = val.u; 3675 break; 3676 case 'h': 3677 if (is_sign) 3678 *va_arg(args, short *) = val.s; 3679 else 3680 *va_arg(args, unsigned short *) = val.u; 3681 break; 3682 case 'l': 3683 if (is_sign) 3684 *va_arg(args, long *) = val.s; 3685 else 3686 *va_arg(args, unsigned long *) = val.u; 3687 break; 3688 case 'L': 3689 if (is_sign) 3690 *va_arg(args, long long *) = val.s; 3691 else 3692 *va_arg(args, unsigned long long *) = val.u; 3693 break; 3694 case 'z': 3695 *va_arg(args, size_t *) = val.u; 3696 break; 3697 default: 3698 if (is_sign) 3699 *va_arg(args, int *) = val.s; 3700 else 3701 *va_arg(args, unsigned int *) = val.u; 3702 break; 3703 } 3704 num++; 3705 3706 if (!next) 3707 break; 3708 str = next; 3709 } 3710 3711 return num; 3712 } 3713 EXPORT_SYMBOL(vsscanf); 3714 3715 /** 3716 * sscanf - Unformat a buffer into a list of arguments 3717 * @buf: input buffer 3718 * @fmt: formatting of buffer 3719 * @...: resulting arguments 3720 */ 3721 int sscanf(const char *buf, const char *fmt, ...) 3722 { 3723 va_list args; 3724 int i; 3725 3726 va_start(args, fmt); 3727 i = vsscanf(buf, fmt, args); 3728 va_end(args); 3729 3730 return i; 3731 } 3732 EXPORT_SYMBOL(sscanf); 3733