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