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