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 DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key); 754 static siphash_key_t ptr_key __read_mostly; 755 756 static void enable_ptr_key_workfn(struct work_struct *work) 757 { 758 get_random_bytes(&ptr_key, sizeof(ptr_key)); 759 /* Needs to run from preemptible context */ 760 static_branch_disable(¬_filled_random_ptr_key); 761 } 762 763 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); 764 765 static int fill_random_ptr_key(struct notifier_block *nb, 766 unsigned long action, void *data) 767 { 768 /* This may be in an interrupt handler. */ 769 queue_work(system_unbound_wq, &enable_ptr_key_work); 770 return 0; 771 } 772 773 static struct notifier_block random_ready = { 774 .notifier_call = fill_random_ptr_key 775 }; 776 777 static int __init initialize_ptr_random(void) 778 { 779 int key_size = sizeof(ptr_key); 780 int ret; 781 782 /* Use hw RNG if available. */ 783 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) { 784 static_branch_disable(¬_filled_random_ptr_key); 785 return 0; 786 } 787 788 ret = register_random_ready_notifier(&random_ready); 789 if (!ret) { 790 return 0; 791 } else if (ret == -EALREADY) { 792 /* This is in preemptible context */ 793 enable_ptr_key_workfn(&enable_ptr_key_work); 794 return 0; 795 } 796 797 return ret; 798 } 799 early_initcall(initialize_ptr_random); 800 801 /* Maps a pointer to a 32 bit unique identifier. */ 802 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 803 { 804 unsigned long hashval; 805 806 if (static_branch_unlikely(¬_filled_random_ptr_key)) 807 return -EAGAIN; 808 809 #ifdef CONFIG_64BIT 810 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 811 /* 812 * Mask off the first 32 bits, this makes explicit that we have 813 * modified the address (and 32 bits is plenty for a unique ID). 814 */ 815 hashval = hashval & 0xffffffff; 816 #else 817 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 818 #endif 819 *hashval_out = hashval; 820 return 0; 821 } 822 823 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 824 { 825 return __ptr_to_hashval(ptr, hashval_out); 826 } 827 828 static char *ptr_to_id(char *buf, char *end, const void *ptr, 829 struct printf_spec spec) 830 { 831 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 832 unsigned long hashval; 833 int ret; 834 835 /* 836 * Print the real pointer value for NULL and error pointers, 837 * as they are not actual addresses. 838 */ 839 if (IS_ERR_OR_NULL(ptr)) 840 return pointer_string(buf, end, ptr, spec); 841 842 /* When debugging early boot use non-cryptographically secure hash. */ 843 if (unlikely(debug_boot_weak_hash)) { 844 hashval = hash_long((unsigned long)ptr, 32); 845 return pointer_string(buf, end, (const void *)hashval, spec); 846 } 847 848 ret = __ptr_to_hashval(ptr, &hashval); 849 if (ret) { 850 spec.field_width = 2 * sizeof(ptr); 851 /* string length must be less than default_width */ 852 return error_string(buf, end, str, spec); 853 } 854 855 return pointer_string(buf, end, (const void *)hashval, spec); 856 } 857 858 static char *default_pointer(char *buf, char *end, const void *ptr, 859 struct printf_spec spec) 860 { 861 /* 862 * default is to _not_ leak addresses, so hash before printing, 863 * unless no_hash_pointers is specified on the command line. 864 */ 865 if (unlikely(no_hash_pointers)) 866 return pointer_string(buf, end, ptr, spec); 867 868 return ptr_to_id(buf, end, ptr, spec); 869 } 870 871 int kptr_restrict __read_mostly; 872 873 static noinline_for_stack 874 char *restricted_pointer(char *buf, char *end, const void *ptr, 875 struct printf_spec spec) 876 { 877 switch (kptr_restrict) { 878 case 0: 879 /* Handle as %p, hash and do _not_ leak addresses. */ 880 return default_pointer(buf, end, ptr, spec); 881 case 1: { 882 const struct cred *cred; 883 884 /* 885 * kptr_restrict==1 cannot be used in IRQ context 886 * because its test for CAP_SYSLOG would be meaningless. 887 */ 888 if (in_irq() || in_serving_softirq() || in_nmi()) { 889 if (spec.field_width == -1) 890 spec.field_width = 2 * sizeof(ptr); 891 return error_string(buf, end, "pK-error", spec); 892 } 893 894 /* 895 * Only print the real pointer value if the current 896 * process has CAP_SYSLOG and is running with the 897 * same credentials it started with. This is because 898 * access to files is checked at open() time, but %pK 899 * checks permission at read() time. We don't want to 900 * leak pointer values if a binary opens a file using 901 * %pK and then elevates privileges before reading it. 902 */ 903 cred = current_cred(); 904 if (!has_capability_noaudit(current, CAP_SYSLOG) || 905 !uid_eq(cred->euid, cred->uid) || 906 !gid_eq(cred->egid, cred->gid)) 907 ptr = NULL; 908 break; 909 } 910 case 2: 911 default: 912 /* Always print 0's for %pK */ 913 ptr = NULL; 914 break; 915 } 916 917 return pointer_string(buf, end, ptr, spec); 918 } 919 920 static noinline_for_stack 921 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 922 const char *fmt) 923 { 924 const char *array[4], *s; 925 const struct dentry *p; 926 int depth; 927 int i, n; 928 929 switch (fmt[1]) { 930 case '2': case '3': case '4': 931 depth = fmt[1] - '0'; 932 break; 933 default: 934 depth = 1; 935 } 936 937 rcu_read_lock(); 938 for (i = 0; i < depth; i++, d = p) { 939 if (check_pointer(&buf, end, d, spec)) { 940 rcu_read_unlock(); 941 return buf; 942 } 943 944 p = READ_ONCE(d->d_parent); 945 array[i] = READ_ONCE(d->d_name.name); 946 if (p == d) { 947 if (i) 948 array[i] = ""; 949 i++; 950 break; 951 } 952 } 953 s = array[--i]; 954 for (n = 0; n != spec.precision; n++, buf++) { 955 char c = *s++; 956 if (!c) { 957 if (!i) 958 break; 959 c = '/'; 960 s = array[--i]; 961 } 962 if (buf < end) 963 *buf = c; 964 } 965 rcu_read_unlock(); 966 return widen_string(buf, n, end, spec); 967 } 968 969 static noinline_for_stack 970 char *file_dentry_name(char *buf, char *end, const struct file *f, 971 struct printf_spec spec, const char *fmt) 972 { 973 if (check_pointer(&buf, end, f, spec)) 974 return buf; 975 976 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 977 } 978 #ifdef CONFIG_BLOCK 979 static noinline_for_stack 980 char *bdev_name(char *buf, char *end, struct block_device *bdev, 981 struct printf_spec spec, const char *fmt) 982 { 983 struct gendisk *hd; 984 985 if (check_pointer(&buf, end, bdev, spec)) 986 return buf; 987 988 hd = bdev->bd_disk; 989 buf = string(buf, end, hd->disk_name, spec); 990 if (bdev->bd_partno) { 991 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 992 if (buf < end) 993 *buf = 'p'; 994 buf++; 995 } 996 buf = number(buf, end, bdev->bd_partno, spec); 997 } 998 return buf; 999 } 1000 #endif 1001 1002 static noinline_for_stack 1003 char *symbol_string(char *buf, char *end, void *ptr, 1004 struct printf_spec spec, const char *fmt) 1005 { 1006 unsigned long value; 1007 #ifdef CONFIG_KALLSYMS 1008 char sym[KSYM_SYMBOL_LEN]; 1009 #endif 1010 1011 if (fmt[1] == 'R') 1012 ptr = __builtin_extract_return_addr(ptr); 1013 value = (unsigned long)ptr; 1014 1015 #ifdef CONFIG_KALLSYMS 1016 if (*fmt == 'B' && fmt[1] == 'b') 1017 sprint_backtrace_build_id(sym, value); 1018 else if (*fmt == 'B') 1019 sprint_backtrace(sym, value); 1020 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 1021 sprint_symbol_build_id(sym, value); 1022 else if (*fmt != 's') 1023 sprint_symbol(sym, value); 1024 else 1025 sprint_symbol_no_offset(sym, value); 1026 1027 return string_nocheck(buf, end, sym, spec); 1028 #else 1029 return special_hex_number(buf, end, value, sizeof(void *)); 1030 #endif 1031 } 1032 1033 static const struct printf_spec default_str_spec = { 1034 .field_width = -1, 1035 .precision = -1, 1036 }; 1037 1038 static const struct printf_spec default_flag_spec = { 1039 .base = 16, 1040 .precision = -1, 1041 .flags = SPECIAL | SMALL, 1042 }; 1043 1044 static const struct printf_spec default_dec_spec = { 1045 .base = 10, 1046 .precision = -1, 1047 }; 1048 1049 static const struct printf_spec default_dec02_spec = { 1050 .base = 10, 1051 .field_width = 2, 1052 .precision = -1, 1053 .flags = ZEROPAD, 1054 }; 1055 1056 static const struct printf_spec default_dec04_spec = { 1057 .base = 10, 1058 .field_width = 4, 1059 .precision = -1, 1060 .flags = ZEROPAD, 1061 }; 1062 1063 static noinline_for_stack 1064 char *resource_string(char *buf, char *end, struct resource *res, 1065 struct printf_spec spec, const char *fmt) 1066 { 1067 #ifndef IO_RSRC_PRINTK_SIZE 1068 #define IO_RSRC_PRINTK_SIZE 6 1069 #endif 1070 1071 #ifndef MEM_RSRC_PRINTK_SIZE 1072 #define MEM_RSRC_PRINTK_SIZE 10 1073 #endif 1074 static const struct printf_spec io_spec = { 1075 .base = 16, 1076 .field_width = IO_RSRC_PRINTK_SIZE, 1077 .precision = -1, 1078 .flags = SPECIAL | SMALL | ZEROPAD, 1079 }; 1080 static const struct printf_spec mem_spec = { 1081 .base = 16, 1082 .field_width = MEM_RSRC_PRINTK_SIZE, 1083 .precision = -1, 1084 .flags = SPECIAL | SMALL | ZEROPAD, 1085 }; 1086 static const struct printf_spec bus_spec = { 1087 .base = 16, 1088 .field_width = 2, 1089 .precision = -1, 1090 .flags = SMALL | ZEROPAD, 1091 }; 1092 static const struct printf_spec str_spec = { 1093 .field_width = -1, 1094 .precision = 10, 1095 .flags = LEFT, 1096 }; 1097 1098 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1099 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1100 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1101 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1102 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1103 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1104 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1105 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1106 1107 char *p = sym, *pend = sym + sizeof(sym); 1108 int decode = (fmt[0] == 'R') ? 1 : 0; 1109 const struct printf_spec *specp; 1110 1111 if (check_pointer(&buf, end, res, spec)) 1112 return buf; 1113 1114 *p++ = '['; 1115 if (res->flags & IORESOURCE_IO) { 1116 p = string_nocheck(p, pend, "io ", str_spec); 1117 specp = &io_spec; 1118 } else if (res->flags & IORESOURCE_MEM) { 1119 p = string_nocheck(p, pend, "mem ", str_spec); 1120 specp = &mem_spec; 1121 } else if (res->flags & IORESOURCE_IRQ) { 1122 p = string_nocheck(p, pend, "irq ", str_spec); 1123 specp = &default_dec_spec; 1124 } else if (res->flags & IORESOURCE_DMA) { 1125 p = string_nocheck(p, pend, "dma ", str_spec); 1126 specp = &default_dec_spec; 1127 } else if (res->flags & IORESOURCE_BUS) { 1128 p = string_nocheck(p, pend, "bus ", str_spec); 1129 specp = &bus_spec; 1130 } else { 1131 p = string_nocheck(p, pend, "??? ", str_spec); 1132 specp = &mem_spec; 1133 decode = 0; 1134 } 1135 if (decode && res->flags & IORESOURCE_UNSET) { 1136 p = string_nocheck(p, pend, "size ", str_spec); 1137 p = number(p, pend, resource_size(res), *specp); 1138 } else { 1139 p = number(p, pend, res->start, *specp); 1140 if (res->start != res->end) { 1141 *p++ = '-'; 1142 p = number(p, pend, res->end, *specp); 1143 } 1144 } 1145 if (decode) { 1146 if (res->flags & IORESOURCE_MEM_64) 1147 p = string_nocheck(p, pend, " 64bit", str_spec); 1148 if (res->flags & IORESOURCE_PREFETCH) 1149 p = string_nocheck(p, pend, " pref", str_spec); 1150 if (res->flags & IORESOURCE_WINDOW) 1151 p = string_nocheck(p, pend, " window", str_spec); 1152 if (res->flags & IORESOURCE_DISABLED) 1153 p = string_nocheck(p, pend, " disabled", str_spec); 1154 } else { 1155 p = string_nocheck(p, pend, " flags ", str_spec); 1156 p = number(p, pend, res->flags, default_flag_spec); 1157 } 1158 *p++ = ']'; 1159 *p = '\0'; 1160 1161 return string_nocheck(buf, end, sym, spec); 1162 } 1163 1164 static noinline_for_stack 1165 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1166 const char *fmt) 1167 { 1168 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1169 negative value, fallback to the default */ 1170 char separator; 1171 1172 if (spec.field_width == 0) 1173 /* nothing to print */ 1174 return buf; 1175 1176 if (check_pointer(&buf, end, addr, spec)) 1177 return buf; 1178 1179 switch (fmt[1]) { 1180 case 'C': 1181 separator = ':'; 1182 break; 1183 case 'D': 1184 separator = '-'; 1185 break; 1186 case 'N': 1187 separator = 0; 1188 break; 1189 default: 1190 separator = ' '; 1191 break; 1192 } 1193 1194 if (spec.field_width > 0) 1195 len = min_t(int, spec.field_width, 64); 1196 1197 for (i = 0; i < len; ++i) { 1198 if (buf < end) 1199 *buf = hex_asc_hi(addr[i]); 1200 ++buf; 1201 if (buf < end) 1202 *buf = hex_asc_lo(addr[i]); 1203 ++buf; 1204 1205 if (separator && i != len - 1) { 1206 if (buf < end) 1207 *buf = separator; 1208 ++buf; 1209 } 1210 } 1211 1212 return buf; 1213 } 1214 1215 static noinline_for_stack 1216 char *bitmap_string(char *buf, char *end, unsigned long *bitmap, 1217 struct printf_spec spec, const char *fmt) 1218 { 1219 const int CHUNKSZ = 32; 1220 int nr_bits = max_t(int, spec.field_width, 0); 1221 int i, chunksz; 1222 bool first = true; 1223 1224 if (check_pointer(&buf, end, bitmap, spec)) 1225 return buf; 1226 1227 /* reused to print numbers */ 1228 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1229 1230 chunksz = nr_bits & (CHUNKSZ - 1); 1231 if (chunksz == 0) 1232 chunksz = CHUNKSZ; 1233 1234 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1235 for (; i >= 0; i -= CHUNKSZ) { 1236 u32 chunkmask, val; 1237 int word, bit; 1238 1239 chunkmask = ((1ULL << chunksz) - 1); 1240 word = i / BITS_PER_LONG; 1241 bit = i % BITS_PER_LONG; 1242 val = (bitmap[word] >> bit) & chunkmask; 1243 1244 if (!first) { 1245 if (buf < end) 1246 *buf = ','; 1247 buf++; 1248 } 1249 first = false; 1250 1251 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1252 buf = number(buf, end, val, spec); 1253 1254 chunksz = CHUNKSZ; 1255 } 1256 return buf; 1257 } 1258 1259 static noinline_for_stack 1260 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap, 1261 struct printf_spec spec, const char *fmt) 1262 { 1263 int nr_bits = max_t(int, spec.field_width, 0); 1264 bool first = true; 1265 int rbot, rtop; 1266 1267 if (check_pointer(&buf, end, bitmap, spec)) 1268 return buf; 1269 1270 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1271 if (!first) { 1272 if (buf < end) 1273 *buf = ','; 1274 buf++; 1275 } 1276 first = false; 1277 1278 buf = number(buf, end, rbot, default_dec_spec); 1279 if (rtop == rbot + 1) 1280 continue; 1281 1282 if (buf < end) 1283 *buf = '-'; 1284 buf = number(++buf, end, rtop - 1, default_dec_spec); 1285 } 1286 return buf; 1287 } 1288 1289 static noinline_for_stack 1290 char *mac_address_string(char *buf, char *end, u8 *addr, 1291 struct printf_spec spec, const char *fmt) 1292 { 1293 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1294 char *p = mac_addr; 1295 int i; 1296 char separator; 1297 bool reversed = false; 1298 1299 if (check_pointer(&buf, end, addr, spec)) 1300 return buf; 1301 1302 switch (fmt[1]) { 1303 case 'F': 1304 separator = '-'; 1305 break; 1306 1307 case 'R': 1308 reversed = true; 1309 fallthrough; 1310 1311 default: 1312 separator = ':'; 1313 break; 1314 } 1315 1316 for (i = 0; i < 6; i++) { 1317 if (reversed) 1318 p = hex_byte_pack(p, addr[5 - i]); 1319 else 1320 p = hex_byte_pack(p, addr[i]); 1321 1322 if (fmt[0] == 'M' && i != 5) 1323 *p++ = separator; 1324 } 1325 *p = '\0'; 1326 1327 return string_nocheck(buf, end, mac_addr, spec); 1328 } 1329 1330 static noinline_for_stack 1331 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1332 { 1333 int i; 1334 bool leading_zeros = (fmt[0] == 'i'); 1335 int index; 1336 int step; 1337 1338 switch (fmt[2]) { 1339 case 'h': 1340 #ifdef __BIG_ENDIAN 1341 index = 0; 1342 step = 1; 1343 #else 1344 index = 3; 1345 step = -1; 1346 #endif 1347 break; 1348 case 'l': 1349 index = 3; 1350 step = -1; 1351 break; 1352 case 'n': 1353 case 'b': 1354 default: 1355 index = 0; 1356 step = 1; 1357 break; 1358 } 1359 for (i = 0; i < 4; i++) { 1360 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1361 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1362 if (leading_zeros) { 1363 if (digits < 3) 1364 *p++ = '0'; 1365 if (digits < 2) 1366 *p++ = '0'; 1367 } 1368 /* reverse the digits in the quad */ 1369 while (digits--) 1370 *p++ = temp[digits]; 1371 if (i < 3) 1372 *p++ = '.'; 1373 index += step; 1374 } 1375 *p = '\0'; 1376 1377 return p; 1378 } 1379 1380 static noinline_for_stack 1381 char *ip6_compressed_string(char *p, const char *addr) 1382 { 1383 int i, j, range; 1384 unsigned char zerolength[8]; 1385 int longest = 1; 1386 int colonpos = -1; 1387 u16 word; 1388 u8 hi, lo; 1389 bool needcolon = false; 1390 bool useIPv4; 1391 struct in6_addr in6; 1392 1393 memcpy(&in6, addr, sizeof(struct in6_addr)); 1394 1395 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1396 1397 memset(zerolength, 0, sizeof(zerolength)); 1398 1399 if (useIPv4) 1400 range = 6; 1401 else 1402 range = 8; 1403 1404 /* find position of longest 0 run */ 1405 for (i = 0; i < range; i++) { 1406 for (j = i; j < range; j++) { 1407 if (in6.s6_addr16[j] != 0) 1408 break; 1409 zerolength[i]++; 1410 } 1411 } 1412 for (i = 0; i < range; i++) { 1413 if (zerolength[i] > longest) { 1414 longest = zerolength[i]; 1415 colonpos = i; 1416 } 1417 } 1418 if (longest == 1) /* don't compress a single 0 */ 1419 colonpos = -1; 1420 1421 /* emit address */ 1422 for (i = 0; i < range; i++) { 1423 if (i == colonpos) { 1424 if (needcolon || i == 0) 1425 *p++ = ':'; 1426 *p++ = ':'; 1427 needcolon = false; 1428 i += longest - 1; 1429 continue; 1430 } 1431 if (needcolon) { 1432 *p++ = ':'; 1433 needcolon = false; 1434 } 1435 /* hex u16 without leading 0s */ 1436 word = ntohs(in6.s6_addr16[i]); 1437 hi = word >> 8; 1438 lo = word & 0xff; 1439 if (hi) { 1440 if (hi > 0x0f) 1441 p = hex_byte_pack(p, hi); 1442 else 1443 *p++ = hex_asc_lo(hi); 1444 p = hex_byte_pack(p, lo); 1445 } 1446 else if (lo > 0x0f) 1447 p = hex_byte_pack(p, lo); 1448 else 1449 *p++ = hex_asc_lo(lo); 1450 needcolon = true; 1451 } 1452 1453 if (useIPv4) { 1454 if (needcolon) 1455 *p++ = ':'; 1456 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1457 } 1458 *p = '\0'; 1459 1460 return p; 1461 } 1462 1463 static noinline_for_stack 1464 char *ip6_string(char *p, const char *addr, const char *fmt) 1465 { 1466 int i; 1467 1468 for (i = 0; i < 8; i++) { 1469 p = hex_byte_pack(p, *addr++); 1470 p = hex_byte_pack(p, *addr++); 1471 if (fmt[0] == 'I' && i != 7) 1472 *p++ = ':'; 1473 } 1474 *p = '\0'; 1475 1476 return p; 1477 } 1478 1479 static noinline_for_stack 1480 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1481 struct printf_spec spec, const char *fmt) 1482 { 1483 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1484 1485 if (fmt[0] == 'I' && fmt[2] == 'c') 1486 ip6_compressed_string(ip6_addr, addr); 1487 else 1488 ip6_string(ip6_addr, addr, fmt); 1489 1490 return string_nocheck(buf, end, ip6_addr, spec); 1491 } 1492 1493 static noinline_for_stack 1494 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1495 struct printf_spec spec, const char *fmt) 1496 { 1497 char ip4_addr[sizeof("255.255.255.255")]; 1498 1499 ip4_string(ip4_addr, addr, fmt); 1500 1501 return string_nocheck(buf, end, ip4_addr, spec); 1502 } 1503 1504 static noinline_for_stack 1505 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1506 struct printf_spec spec, const char *fmt) 1507 { 1508 bool have_p = false, have_s = false, have_f = false, have_c = false; 1509 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1510 sizeof(":12345") + sizeof("/123456789") + 1511 sizeof("%1234567890")]; 1512 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1513 const u8 *addr = (const u8 *) &sa->sin6_addr; 1514 char fmt6[2] = { fmt[0], '6' }; 1515 u8 off = 0; 1516 1517 fmt++; 1518 while (isalpha(*++fmt)) { 1519 switch (*fmt) { 1520 case 'p': 1521 have_p = true; 1522 break; 1523 case 'f': 1524 have_f = true; 1525 break; 1526 case 's': 1527 have_s = true; 1528 break; 1529 case 'c': 1530 have_c = true; 1531 break; 1532 } 1533 } 1534 1535 if (have_p || have_s || have_f) { 1536 *p = '['; 1537 off = 1; 1538 } 1539 1540 if (fmt6[0] == 'I' && have_c) 1541 p = ip6_compressed_string(ip6_addr + off, addr); 1542 else 1543 p = ip6_string(ip6_addr + off, addr, fmt6); 1544 1545 if (have_p || have_s || have_f) 1546 *p++ = ']'; 1547 1548 if (have_p) { 1549 *p++ = ':'; 1550 p = number(p, pend, ntohs(sa->sin6_port), spec); 1551 } 1552 if (have_f) { 1553 *p++ = '/'; 1554 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1555 IPV6_FLOWINFO_MASK), spec); 1556 } 1557 if (have_s) { 1558 *p++ = '%'; 1559 p = number(p, pend, sa->sin6_scope_id, spec); 1560 } 1561 *p = '\0'; 1562 1563 return string_nocheck(buf, end, ip6_addr, spec); 1564 } 1565 1566 static noinline_for_stack 1567 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1568 struct printf_spec spec, const char *fmt) 1569 { 1570 bool have_p = false; 1571 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1572 char *pend = ip4_addr + sizeof(ip4_addr); 1573 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1574 char fmt4[3] = { fmt[0], '4', 0 }; 1575 1576 fmt++; 1577 while (isalpha(*++fmt)) { 1578 switch (*fmt) { 1579 case 'p': 1580 have_p = true; 1581 break; 1582 case 'h': 1583 case 'l': 1584 case 'n': 1585 case 'b': 1586 fmt4[2] = *fmt; 1587 break; 1588 } 1589 } 1590 1591 p = ip4_string(ip4_addr, addr, fmt4); 1592 if (have_p) { 1593 *p++ = ':'; 1594 p = number(p, pend, ntohs(sa->sin_port), spec); 1595 } 1596 *p = '\0'; 1597 1598 return string_nocheck(buf, end, ip4_addr, spec); 1599 } 1600 1601 static noinline_for_stack 1602 char *ip_addr_string(char *buf, char *end, const void *ptr, 1603 struct printf_spec spec, const char *fmt) 1604 { 1605 char *err_fmt_msg; 1606 1607 if (check_pointer(&buf, end, ptr, spec)) 1608 return buf; 1609 1610 switch (fmt[1]) { 1611 case '6': 1612 return ip6_addr_string(buf, end, ptr, spec, fmt); 1613 case '4': 1614 return ip4_addr_string(buf, end, ptr, spec, fmt); 1615 case 'S': { 1616 const union { 1617 struct sockaddr raw; 1618 struct sockaddr_in v4; 1619 struct sockaddr_in6 v6; 1620 } *sa = ptr; 1621 1622 switch (sa->raw.sa_family) { 1623 case AF_INET: 1624 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1625 case AF_INET6: 1626 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1627 default: 1628 return error_string(buf, end, "(einval)", spec); 1629 }} 1630 } 1631 1632 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1633 return error_string(buf, end, err_fmt_msg, spec); 1634 } 1635 1636 static noinline_for_stack 1637 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1638 const char *fmt) 1639 { 1640 bool found = true; 1641 int count = 1; 1642 unsigned int flags = 0; 1643 int len; 1644 1645 if (spec.field_width == 0) 1646 return buf; /* nothing to print */ 1647 1648 if (check_pointer(&buf, end, addr, spec)) 1649 return buf; 1650 1651 do { 1652 switch (fmt[count++]) { 1653 case 'a': 1654 flags |= ESCAPE_ANY; 1655 break; 1656 case 'c': 1657 flags |= ESCAPE_SPECIAL; 1658 break; 1659 case 'h': 1660 flags |= ESCAPE_HEX; 1661 break; 1662 case 'n': 1663 flags |= ESCAPE_NULL; 1664 break; 1665 case 'o': 1666 flags |= ESCAPE_OCTAL; 1667 break; 1668 case 'p': 1669 flags |= ESCAPE_NP; 1670 break; 1671 case 's': 1672 flags |= ESCAPE_SPACE; 1673 break; 1674 default: 1675 found = false; 1676 break; 1677 } 1678 } while (found); 1679 1680 if (!flags) 1681 flags = ESCAPE_ANY_NP; 1682 1683 len = spec.field_width < 0 ? 1 : spec.field_width; 1684 1685 /* 1686 * string_escape_mem() writes as many characters as it can to 1687 * the given buffer, and returns the total size of the output 1688 * had the buffer been big enough. 1689 */ 1690 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1691 1692 return buf; 1693 } 1694 1695 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1696 struct printf_spec spec, const char *fmt) 1697 { 1698 va_list va; 1699 1700 if (check_pointer(&buf, end, va_fmt, spec)) 1701 return buf; 1702 1703 va_copy(va, *va_fmt->va); 1704 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1705 va_end(va); 1706 1707 return buf; 1708 } 1709 1710 static noinline_for_stack 1711 char *uuid_string(char *buf, char *end, const u8 *addr, 1712 struct printf_spec spec, const char *fmt) 1713 { 1714 char uuid[UUID_STRING_LEN + 1]; 1715 char *p = uuid; 1716 int i; 1717 const u8 *index = uuid_index; 1718 bool uc = false; 1719 1720 if (check_pointer(&buf, end, addr, spec)) 1721 return buf; 1722 1723 switch (*(++fmt)) { 1724 case 'L': 1725 uc = true; 1726 fallthrough; 1727 case 'l': 1728 index = guid_index; 1729 break; 1730 case 'B': 1731 uc = true; 1732 break; 1733 } 1734 1735 for (i = 0; i < 16; i++) { 1736 if (uc) 1737 p = hex_byte_pack_upper(p, addr[index[i]]); 1738 else 1739 p = hex_byte_pack(p, addr[index[i]]); 1740 switch (i) { 1741 case 3: 1742 case 5: 1743 case 7: 1744 case 9: 1745 *p++ = '-'; 1746 break; 1747 } 1748 } 1749 1750 *p = 0; 1751 1752 return string_nocheck(buf, end, uuid, spec); 1753 } 1754 1755 static noinline_for_stack 1756 char *netdev_bits(char *buf, char *end, const void *addr, 1757 struct printf_spec spec, const char *fmt) 1758 { 1759 unsigned long long num; 1760 int size; 1761 1762 if (check_pointer(&buf, end, addr, spec)) 1763 return buf; 1764 1765 switch (fmt[1]) { 1766 case 'F': 1767 num = *(const netdev_features_t *)addr; 1768 size = sizeof(netdev_features_t); 1769 break; 1770 default: 1771 return error_string(buf, end, "(%pN?)", spec); 1772 } 1773 1774 return special_hex_number(buf, end, num, size); 1775 } 1776 1777 static noinline_for_stack 1778 char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1779 struct printf_spec spec, const char *fmt) 1780 { 1781 char output[sizeof("0123 little-endian (0x01234567)")]; 1782 char *p = output; 1783 unsigned int i; 1784 u32 orig, val; 1785 1786 if (fmt[1] != 'c' || fmt[2] != 'c') 1787 return error_string(buf, end, "(%p4?)", spec); 1788 1789 if (check_pointer(&buf, end, fourcc, spec)) 1790 return buf; 1791 1792 orig = get_unaligned(fourcc); 1793 val = orig & ~BIT(31); 1794 1795 for (i = 0; i < sizeof(u32); i++) { 1796 unsigned char c = val >> (i * 8); 1797 1798 /* Print non-control ASCII characters as-is, dot otherwise */ 1799 *p++ = isascii(c) && isprint(c) ? c : '.'; 1800 } 1801 1802 *p++ = ' '; 1803 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1804 p += strlen(p); 1805 1806 *p++ = ' '; 1807 *p++ = '('; 1808 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1809 *p++ = ')'; 1810 *p = '\0'; 1811 1812 return string(buf, end, output, spec); 1813 } 1814 1815 static noinline_for_stack 1816 char *address_val(char *buf, char *end, const void *addr, 1817 struct printf_spec spec, const char *fmt) 1818 { 1819 unsigned long long num; 1820 int size; 1821 1822 if (check_pointer(&buf, end, addr, spec)) 1823 return buf; 1824 1825 switch (fmt[1]) { 1826 case 'd': 1827 num = *(const dma_addr_t *)addr; 1828 size = sizeof(dma_addr_t); 1829 break; 1830 case 'p': 1831 default: 1832 num = *(const phys_addr_t *)addr; 1833 size = sizeof(phys_addr_t); 1834 break; 1835 } 1836 1837 return special_hex_number(buf, end, num, size); 1838 } 1839 1840 static noinline_for_stack 1841 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1842 { 1843 int year = tm->tm_year + (r ? 0 : 1900); 1844 int mon = tm->tm_mon + (r ? 0 : 1); 1845 1846 buf = number(buf, end, year, default_dec04_spec); 1847 if (buf < end) 1848 *buf = '-'; 1849 buf++; 1850 1851 buf = number(buf, end, mon, default_dec02_spec); 1852 if (buf < end) 1853 *buf = '-'; 1854 buf++; 1855 1856 return number(buf, end, tm->tm_mday, default_dec02_spec); 1857 } 1858 1859 static noinline_for_stack 1860 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1861 { 1862 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1863 if (buf < end) 1864 *buf = ':'; 1865 buf++; 1866 1867 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1868 if (buf < end) 1869 *buf = ':'; 1870 buf++; 1871 1872 return number(buf, end, tm->tm_sec, default_dec02_spec); 1873 } 1874 1875 static noinline_for_stack 1876 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1877 struct printf_spec spec, const char *fmt) 1878 { 1879 bool have_t = true, have_d = true; 1880 bool raw = false, iso8601_separator = true; 1881 bool found = true; 1882 int count = 2; 1883 1884 if (check_pointer(&buf, end, tm, spec)) 1885 return buf; 1886 1887 switch (fmt[count]) { 1888 case 'd': 1889 have_t = false; 1890 count++; 1891 break; 1892 case 't': 1893 have_d = false; 1894 count++; 1895 break; 1896 } 1897 1898 do { 1899 switch (fmt[count++]) { 1900 case 'r': 1901 raw = true; 1902 break; 1903 case 's': 1904 iso8601_separator = false; 1905 break; 1906 default: 1907 found = false; 1908 break; 1909 } 1910 } while (found); 1911 1912 if (have_d) 1913 buf = date_str(buf, end, tm, raw); 1914 if (have_d && have_t) { 1915 if (buf < end) 1916 *buf = iso8601_separator ? 'T' : ' '; 1917 buf++; 1918 } 1919 if (have_t) 1920 buf = time_str(buf, end, tm, raw); 1921 1922 return buf; 1923 } 1924 1925 static noinline_for_stack 1926 char *time64_str(char *buf, char *end, const time64_t time, 1927 struct printf_spec spec, const char *fmt) 1928 { 1929 struct rtc_time rtc_time; 1930 struct tm tm; 1931 1932 time64_to_tm(time, 0, &tm); 1933 1934 rtc_time.tm_sec = tm.tm_sec; 1935 rtc_time.tm_min = tm.tm_min; 1936 rtc_time.tm_hour = tm.tm_hour; 1937 rtc_time.tm_mday = tm.tm_mday; 1938 rtc_time.tm_mon = tm.tm_mon; 1939 rtc_time.tm_year = tm.tm_year; 1940 rtc_time.tm_wday = tm.tm_wday; 1941 rtc_time.tm_yday = tm.tm_yday; 1942 1943 rtc_time.tm_isdst = 0; 1944 1945 return rtc_str(buf, end, &rtc_time, spec, fmt); 1946 } 1947 1948 static noinline_for_stack 1949 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1950 const char *fmt) 1951 { 1952 switch (fmt[1]) { 1953 case 'R': 1954 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1955 case 'T': 1956 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 1957 default: 1958 return error_string(buf, end, "(%pt?)", spec); 1959 } 1960 } 1961 1962 static noinline_for_stack 1963 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1964 const char *fmt) 1965 { 1966 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1967 return error_string(buf, end, "(%pC?)", spec); 1968 1969 if (check_pointer(&buf, end, clk, spec)) 1970 return buf; 1971 1972 switch (fmt[1]) { 1973 case 'n': 1974 default: 1975 #ifdef CONFIG_COMMON_CLK 1976 return string(buf, end, __clk_get_name(clk), spec); 1977 #else 1978 return ptr_to_id(buf, end, clk, spec); 1979 #endif 1980 } 1981 } 1982 1983 static 1984 char *format_flags(char *buf, char *end, unsigned long flags, 1985 const struct trace_print_flags *names) 1986 { 1987 unsigned long mask; 1988 1989 for ( ; flags && names->name; names++) { 1990 mask = names->mask; 1991 if ((flags & mask) != mask) 1992 continue; 1993 1994 buf = string(buf, end, names->name, default_str_spec); 1995 1996 flags &= ~mask; 1997 if (flags) { 1998 if (buf < end) 1999 *buf = '|'; 2000 buf++; 2001 } 2002 } 2003 2004 if (flags) 2005 buf = number(buf, end, flags, default_flag_spec); 2006 2007 return buf; 2008 } 2009 2010 struct page_flags_fields { 2011 int width; 2012 int shift; 2013 int mask; 2014 const struct printf_spec *spec; 2015 const char *name; 2016 }; 2017 2018 static const struct page_flags_fields pff[] = { 2019 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 2020 &default_dec_spec, "section"}, 2021 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2022 &default_dec_spec, "node"}, 2023 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2024 &default_dec_spec, "zone"}, 2025 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2026 &default_flag_spec, "lastcpupid"}, 2027 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2028 &default_flag_spec, "kasantag"}, 2029 }; 2030 2031 static 2032 char *format_page_flags(char *buf, char *end, unsigned long flags) 2033 { 2034 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2035 bool append = false; 2036 int i; 2037 2038 buf = number(buf, end, flags, default_flag_spec); 2039 if (buf < end) 2040 *buf = '('; 2041 buf++; 2042 2043 /* Page flags from the main area. */ 2044 if (main_flags) { 2045 buf = format_flags(buf, end, main_flags, pageflag_names); 2046 append = true; 2047 } 2048 2049 /* Page flags from the fields area */ 2050 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2051 /* Skip undefined fields. */ 2052 if (!pff[i].width) 2053 continue; 2054 2055 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2056 if (append) { 2057 if (buf < end) 2058 *buf = '|'; 2059 buf++; 2060 } 2061 2062 buf = string(buf, end, pff[i].name, default_str_spec); 2063 if (buf < end) 2064 *buf = '='; 2065 buf++; 2066 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2067 *pff[i].spec); 2068 2069 append = true; 2070 } 2071 if (buf < end) 2072 *buf = ')'; 2073 buf++; 2074 2075 return buf; 2076 } 2077 2078 static noinline_for_stack 2079 char *flags_string(char *buf, char *end, void *flags_ptr, 2080 struct printf_spec spec, const char *fmt) 2081 { 2082 unsigned long flags; 2083 const struct trace_print_flags *names; 2084 2085 if (check_pointer(&buf, end, flags_ptr, spec)) 2086 return buf; 2087 2088 switch (fmt[1]) { 2089 case 'p': 2090 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2091 case 'v': 2092 flags = *(unsigned long *)flags_ptr; 2093 names = vmaflag_names; 2094 break; 2095 case 'g': 2096 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2097 names = gfpflag_names; 2098 break; 2099 default: 2100 return error_string(buf, end, "(%pG?)", spec); 2101 } 2102 2103 return format_flags(buf, end, flags, names); 2104 } 2105 2106 static noinline_for_stack 2107 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2108 char *end) 2109 { 2110 int depth; 2111 2112 /* Loop starting from the root node to the current node. */ 2113 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2114 struct fwnode_handle *__fwnode = 2115 fwnode_get_nth_parent(fwnode, depth); 2116 2117 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2118 default_str_spec); 2119 buf = string(buf, end, fwnode_get_name(__fwnode), 2120 default_str_spec); 2121 2122 fwnode_handle_put(__fwnode); 2123 } 2124 2125 return buf; 2126 } 2127 2128 static noinline_for_stack 2129 char *device_node_string(char *buf, char *end, struct device_node *dn, 2130 struct printf_spec spec, const char *fmt) 2131 { 2132 char tbuf[sizeof("xxxx") + 1]; 2133 const char *p; 2134 int ret; 2135 char *buf_start = buf; 2136 struct property *prop; 2137 bool has_mult, pass; 2138 2139 struct printf_spec str_spec = spec; 2140 str_spec.field_width = -1; 2141 2142 if (fmt[0] != 'F') 2143 return error_string(buf, end, "(%pO?)", spec); 2144 2145 if (!IS_ENABLED(CONFIG_OF)) 2146 return error_string(buf, end, "(%pOF?)", spec); 2147 2148 if (check_pointer(&buf, end, dn, spec)) 2149 return buf; 2150 2151 /* simple case without anything any more format specifiers */ 2152 fmt++; 2153 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2154 fmt = "f"; 2155 2156 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2157 int precision; 2158 if (pass) { 2159 if (buf < end) 2160 *buf = ':'; 2161 buf++; 2162 } 2163 2164 switch (*fmt) { 2165 case 'f': /* full_name */ 2166 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2167 end); 2168 break; 2169 case 'n': /* name */ 2170 p = fwnode_get_name(of_fwnode_handle(dn)); 2171 precision = str_spec.precision; 2172 str_spec.precision = strchrnul(p, '@') - p; 2173 buf = string(buf, end, p, str_spec); 2174 str_spec.precision = precision; 2175 break; 2176 case 'p': /* phandle */ 2177 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2178 break; 2179 case 'P': /* path-spec */ 2180 p = fwnode_get_name(of_fwnode_handle(dn)); 2181 if (!p[1]) 2182 p = "/"; 2183 buf = string(buf, end, p, str_spec); 2184 break; 2185 case 'F': /* flags */ 2186 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2187 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2188 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2189 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2190 tbuf[4] = 0; 2191 buf = string_nocheck(buf, end, tbuf, str_spec); 2192 break; 2193 case 'c': /* major compatible string */ 2194 ret = of_property_read_string(dn, "compatible", &p); 2195 if (!ret) 2196 buf = string(buf, end, p, str_spec); 2197 break; 2198 case 'C': /* full compatible string */ 2199 has_mult = false; 2200 of_property_for_each_string(dn, "compatible", prop, p) { 2201 if (has_mult) 2202 buf = string_nocheck(buf, end, ",", str_spec); 2203 buf = string_nocheck(buf, end, "\"", str_spec); 2204 buf = string(buf, end, p, str_spec); 2205 buf = string_nocheck(buf, end, "\"", str_spec); 2206 2207 has_mult = true; 2208 } 2209 break; 2210 default: 2211 break; 2212 } 2213 } 2214 2215 return widen_string(buf, buf - buf_start, end, spec); 2216 } 2217 2218 static noinline_for_stack 2219 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2220 struct printf_spec spec, const char *fmt) 2221 { 2222 struct printf_spec str_spec = spec; 2223 char *buf_start = buf; 2224 2225 str_spec.field_width = -1; 2226 2227 if (*fmt != 'w') 2228 return error_string(buf, end, "(%pf?)", spec); 2229 2230 if (check_pointer(&buf, end, fwnode, spec)) 2231 return buf; 2232 2233 fmt++; 2234 2235 switch (*fmt) { 2236 case 'P': /* name */ 2237 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2238 break; 2239 case 'f': /* full_name */ 2240 default: 2241 buf = fwnode_full_name_string(fwnode, buf, end); 2242 break; 2243 } 2244 2245 return widen_string(buf, buf - buf_start, end, spec); 2246 } 2247 2248 int __init no_hash_pointers_enable(char *str) 2249 { 2250 if (no_hash_pointers) 2251 return 0; 2252 2253 no_hash_pointers = true; 2254 2255 pr_warn("**********************************************************\n"); 2256 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2257 pr_warn("** **\n"); 2258 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2259 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2260 pr_warn("** might reduce the security of your system. **\n"); 2261 pr_warn("** **\n"); 2262 pr_warn("** If you see this message and you are not debugging **\n"); 2263 pr_warn("** the kernel, report this immediately to your system **\n"); 2264 pr_warn("** administrator! **\n"); 2265 pr_warn("** **\n"); 2266 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2267 pr_warn("**********************************************************\n"); 2268 2269 return 0; 2270 } 2271 early_param("no_hash_pointers", no_hash_pointers_enable); 2272 2273 /* 2274 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2275 * by an extra set of alphanumeric characters that are extended format 2276 * specifiers. 2277 * 2278 * Please update scripts/checkpatch.pl when adding/removing conversion 2279 * characters. (Search for "check for vsprintf extension"). 2280 * 2281 * Right now we handle: 2282 * 2283 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2284 * - 's' For symbolic direct pointers (or function descriptors) without offset 2285 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2286 * - 'S[R]b' as above with module build ID (for use in backtraces) 2287 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2288 * %ps and %pS. Be careful when re-using these specifiers. 2289 * - 'B' For backtraced symbolic direct pointers with offset 2290 * - 'Bb' as above with module build ID (for use in backtraces) 2291 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2292 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2293 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2294 * width which must be explicitly specified either as part of the 2295 * format string '%32b[l]' or through '%*b[l]', [l] selects 2296 * range-list format instead of hex format 2297 * - 'M' For a 6-byte MAC address, it prints the address in the 2298 * usual colon-separated hex notation 2299 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2300 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2301 * with a dash-separated hex notation 2302 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2303 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2304 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2305 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2306 * [S][pfs] 2307 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2308 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2309 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2310 * IPv6 omits the colons (01020304...0f) 2311 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2312 * [S][pfs] 2313 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2314 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2315 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2316 * - 'I[6S]c' for IPv6 addresses printed as specified by 2317 * https://tools.ietf.org/html/rfc5952 2318 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2319 * of the following flags (see string_escape_mem() for the 2320 * details): 2321 * a - ESCAPE_ANY 2322 * c - ESCAPE_SPECIAL 2323 * h - ESCAPE_HEX 2324 * n - ESCAPE_NULL 2325 * o - ESCAPE_OCTAL 2326 * p - ESCAPE_NP 2327 * s - ESCAPE_SPACE 2328 * By default ESCAPE_ANY_NP is used. 2329 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2330 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2331 * Options for %pU are: 2332 * b big endian lower case hex (default) 2333 * B big endian UPPER case hex 2334 * l little endian lower case hex 2335 * L little endian UPPER case hex 2336 * big endian output byte order is: 2337 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2338 * little endian output byte order is: 2339 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2340 * - 'V' For a struct va_format which contains a format string * and va_list *, 2341 * call vsnprintf(->format, *->va_list). 2342 * Implements a "recursive vsnprintf". 2343 * Do not use this feature without some mechanism to verify the 2344 * correctness of the format string and va_list arguments. 2345 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2346 * Use only for procfs, sysfs and similar files, not printk(); please 2347 * read the documentation (path below) first. 2348 * - 'NF' For a netdev_features_t 2349 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2350 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2351 * a certain separator (' ' by default): 2352 * C colon 2353 * D dash 2354 * N no separator 2355 * The maximum supported length is 64 bytes of the input. Consider 2356 * to use print_hex_dump() for the larger input. 2357 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2358 * (default assumed to be phys_addr_t, passed by reference) 2359 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2360 * - 'D[234]' Same as 'd' but for a struct file 2361 * - 'g' For block_device name (gendisk + partition number) 2362 * - 't[RT][dt][r][s]' For time and date as represented by: 2363 * R struct rtc_time 2364 * T time64_t 2365 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2366 * (legacy clock framework) of the clock 2367 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2368 * (legacy clock framework) of the clock 2369 * - 'G' For flags to be printed as a collection of symbolic strings that would 2370 * construct the specific value. Supported flags given by option: 2371 * p page flags (see struct page) given as pointer to unsigned long 2372 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2373 * v vma flags (VM_*) given as pointer to unsigned long 2374 * - 'OF[fnpPcCF]' For a device tree object 2375 * Without any optional arguments prints the full_name 2376 * f device node full_name 2377 * n device node name 2378 * p device node phandle 2379 * P device node path spec (name + @unit) 2380 * F device node flags 2381 * c major compatible string 2382 * C full compatible string 2383 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2384 * Without an option prints the full name of the node 2385 * f full name 2386 * P node name, including a possible unit address 2387 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2388 * Please read the documentation (path below) before using! 2389 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2390 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2391 * or user (u) memory to probe, and: 2392 * s a string, equivalent to "%s" on direct vsnprintf() use 2393 * 2394 * ** When making changes please also update: 2395 * Documentation/core-api/printk-formats.rst 2396 * 2397 * Note: The default behaviour (unadorned %p) is to hash the address, 2398 * rendering it useful as a unique identifier. 2399 */ 2400 static noinline_for_stack 2401 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2402 struct printf_spec spec) 2403 { 2404 switch (*fmt) { 2405 case 'S': 2406 case 's': 2407 ptr = dereference_symbol_descriptor(ptr); 2408 fallthrough; 2409 case 'B': 2410 return symbol_string(buf, end, ptr, spec, fmt); 2411 case 'R': 2412 case 'r': 2413 return resource_string(buf, end, ptr, spec, fmt); 2414 case 'h': 2415 return hex_string(buf, end, ptr, spec, fmt); 2416 case 'b': 2417 switch (fmt[1]) { 2418 case 'l': 2419 return bitmap_list_string(buf, end, ptr, spec, fmt); 2420 default: 2421 return bitmap_string(buf, end, ptr, spec, fmt); 2422 } 2423 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2424 case 'm': /* Contiguous: 000102030405 */ 2425 /* [mM]F (FDDI) */ 2426 /* [mM]R (Reverse order; Bluetooth) */ 2427 return mac_address_string(buf, end, ptr, spec, fmt); 2428 case 'I': /* Formatted IP supported 2429 * 4: 1.2.3.4 2430 * 6: 0001:0203:...:0708 2431 * 6c: 1::708 or 1::1.2.3.4 2432 */ 2433 case 'i': /* Contiguous: 2434 * 4: 001.002.003.004 2435 * 6: 000102...0f 2436 */ 2437 return ip_addr_string(buf, end, ptr, spec, fmt); 2438 case 'E': 2439 return escaped_string(buf, end, ptr, spec, fmt); 2440 case 'U': 2441 return uuid_string(buf, end, ptr, spec, fmt); 2442 case 'V': 2443 return va_format(buf, end, ptr, spec, fmt); 2444 case 'K': 2445 return restricted_pointer(buf, end, ptr, spec); 2446 case 'N': 2447 return netdev_bits(buf, end, ptr, spec, fmt); 2448 case '4': 2449 return fourcc_string(buf, end, ptr, spec, fmt); 2450 case 'a': 2451 return address_val(buf, end, ptr, spec, fmt); 2452 case 'd': 2453 return dentry_name(buf, end, ptr, spec, fmt); 2454 case 't': 2455 return time_and_date(buf, end, ptr, spec, fmt); 2456 case 'C': 2457 return clock(buf, end, ptr, spec, fmt); 2458 case 'D': 2459 return file_dentry_name(buf, end, ptr, spec, fmt); 2460 #ifdef CONFIG_BLOCK 2461 case 'g': 2462 return bdev_name(buf, end, ptr, spec, fmt); 2463 #endif 2464 2465 case 'G': 2466 return flags_string(buf, end, ptr, spec, fmt); 2467 case 'O': 2468 return device_node_string(buf, end, ptr, spec, fmt + 1); 2469 case 'f': 2470 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2471 case 'x': 2472 return pointer_string(buf, end, ptr, spec); 2473 case 'e': 2474 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2475 if (!IS_ERR(ptr)) 2476 return default_pointer(buf, end, ptr, spec); 2477 return err_ptr(buf, end, ptr, spec); 2478 case 'u': 2479 case 'k': 2480 switch (fmt[1]) { 2481 case 's': 2482 return string(buf, end, ptr, spec); 2483 default: 2484 return error_string(buf, end, "(einval)", spec); 2485 } 2486 default: 2487 return default_pointer(buf, end, ptr, spec); 2488 } 2489 } 2490 2491 /* 2492 * Helper function to decode printf style format. 2493 * Each call decode a token from the format and return the 2494 * number of characters read (or likely the delta where it wants 2495 * to go on the next call). 2496 * The decoded token is returned through the parameters 2497 * 2498 * 'h', 'l', or 'L' for integer fields 2499 * 'z' support added 23/7/1999 S.H. 2500 * 'z' changed to 'Z' --davidm 1/25/99 2501 * 'Z' changed to 'z' --adobriyan 2017-01-25 2502 * 't' added for ptrdiff_t 2503 * 2504 * @fmt: the format string 2505 * @type of the token returned 2506 * @flags: various flags such as +, -, # tokens.. 2507 * @field_width: overwritten width 2508 * @base: base of the number (octal, hex, ...) 2509 * @precision: precision of a number 2510 * @qualifier: qualifier of a number (long, size_t, ...) 2511 */ 2512 static noinline_for_stack 2513 int format_decode(const char *fmt, struct printf_spec *spec) 2514 { 2515 const char *start = fmt; 2516 char qualifier; 2517 2518 /* we finished early by reading the field width */ 2519 if (spec->type == FORMAT_TYPE_WIDTH) { 2520 if (spec->field_width < 0) { 2521 spec->field_width = -spec->field_width; 2522 spec->flags |= LEFT; 2523 } 2524 spec->type = FORMAT_TYPE_NONE; 2525 goto precision; 2526 } 2527 2528 /* we finished early by reading the precision */ 2529 if (spec->type == FORMAT_TYPE_PRECISION) { 2530 if (spec->precision < 0) 2531 spec->precision = 0; 2532 2533 spec->type = FORMAT_TYPE_NONE; 2534 goto qualifier; 2535 } 2536 2537 /* By default */ 2538 spec->type = FORMAT_TYPE_NONE; 2539 2540 for (; *fmt ; ++fmt) { 2541 if (*fmt == '%') 2542 break; 2543 } 2544 2545 /* Return the current non-format string */ 2546 if (fmt != start || !*fmt) 2547 return fmt - start; 2548 2549 /* Process flags */ 2550 spec->flags = 0; 2551 2552 while (1) { /* this also skips first '%' */ 2553 bool found = true; 2554 2555 ++fmt; 2556 2557 switch (*fmt) { 2558 case '-': spec->flags |= LEFT; break; 2559 case '+': spec->flags |= PLUS; break; 2560 case ' ': spec->flags |= SPACE; break; 2561 case '#': spec->flags |= SPECIAL; break; 2562 case '0': spec->flags |= ZEROPAD; break; 2563 default: found = false; 2564 } 2565 2566 if (!found) 2567 break; 2568 } 2569 2570 /* get field width */ 2571 spec->field_width = -1; 2572 2573 if (isdigit(*fmt)) 2574 spec->field_width = skip_atoi(&fmt); 2575 else if (*fmt == '*') { 2576 /* it's the next argument */ 2577 spec->type = FORMAT_TYPE_WIDTH; 2578 return ++fmt - start; 2579 } 2580 2581 precision: 2582 /* get the precision */ 2583 spec->precision = -1; 2584 if (*fmt == '.') { 2585 ++fmt; 2586 if (isdigit(*fmt)) { 2587 spec->precision = skip_atoi(&fmt); 2588 if (spec->precision < 0) 2589 spec->precision = 0; 2590 } else if (*fmt == '*') { 2591 /* it's the next argument */ 2592 spec->type = FORMAT_TYPE_PRECISION; 2593 return ++fmt - start; 2594 } 2595 } 2596 2597 qualifier: 2598 /* get the conversion qualifier */ 2599 qualifier = 0; 2600 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2601 *fmt == 'z' || *fmt == 't') { 2602 qualifier = *fmt++; 2603 if (unlikely(qualifier == *fmt)) { 2604 if (qualifier == 'l') { 2605 qualifier = 'L'; 2606 ++fmt; 2607 } else if (qualifier == 'h') { 2608 qualifier = 'H'; 2609 ++fmt; 2610 } 2611 } 2612 } 2613 2614 /* default base */ 2615 spec->base = 10; 2616 switch (*fmt) { 2617 case 'c': 2618 spec->type = FORMAT_TYPE_CHAR; 2619 return ++fmt - start; 2620 2621 case 's': 2622 spec->type = FORMAT_TYPE_STR; 2623 return ++fmt - start; 2624 2625 case 'p': 2626 spec->type = FORMAT_TYPE_PTR; 2627 return ++fmt - start; 2628 2629 case '%': 2630 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2631 return ++fmt - start; 2632 2633 /* integer number formats - set up the flags and "break" */ 2634 case 'o': 2635 spec->base = 8; 2636 break; 2637 2638 case 'x': 2639 spec->flags |= SMALL; 2640 fallthrough; 2641 2642 case 'X': 2643 spec->base = 16; 2644 break; 2645 2646 case 'd': 2647 case 'i': 2648 spec->flags |= SIGN; 2649 break; 2650 case 'u': 2651 break; 2652 2653 case 'n': 2654 /* 2655 * Since %n poses a greater security risk than 2656 * utility, treat it as any other invalid or 2657 * unsupported format specifier. 2658 */ 2659 fallthrough; 2660 2661 default: 2662 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2663 spec->type = FORMAT_TYPE_INVALID; 2664 return fmt - start; 2665 } 2666 2667 if (qualifier == 'L') 2668 spec->type = FORMAT_TYPE_LONG_LONG; 2669 else if (qualifier == 'l') { 2670 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2671 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2672 } else if (qualifier == 'z') { 2673 spec->type = FORMAT_TYPE_SIZE_T; 2674 } else if (qualifier == 't') { 2675 spec->type = FORMAT_TYPE_PTRDIFF; 2676 } else if (qualifier == 'H') { 2677 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2678 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2679 } else if (qualifier == 'h') { 2680 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2681 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2682 } else { 2683 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2684 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2685 } 2686 2687 return ++fmt - start; 2688 } 2689 2690 static void 2691 set_field_width(struct printf_spec *spec, int width) 2692 { 2693 spec->field_width = width; 2694 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2695 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2696 } 2697 } 2698 2699 static void 2700 set_precision(struct printf_spec *spec, int prec) 2701 { 2702 spec->precision = prec; 2703 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2704 spec->precision = clamp(prec, 0, PRECISION_MAX); 2705 } 2706 } 2707 2708 /** 2709 * vsnprintf - Format a string and place it in a buffer 2710 * @buf: The buffer to place the result into 2711 * @size: The size of the buffer, including the trailing null space 2712 * @fmt: The format string to use 2713 * @args: Arguments for the format string 2714 * 2715 * This function generally follows C99 vsnprintf, but has some 2716 * extensions and a few limitations: 2717 * 2718 * - ``%n`` is unsupported 2719 * - ``%p*`` is handled by pointer() 2720 * 2721 * See pointer() or Documentation/core-api/printk-formats.rst for more 2722 * extensive description. 2723 * 2724 * **Please update the documentation in both places when making changes** 2725 * 2726 * The return value is the number of characters which would 2727 * be generated for the given input, excluding the trailing 2728 * '\0', as per ISO C99. If you want to have the exact 2729 * number of characters written into @buf as return value 2730 * (not including the trailing '\0'), use vscnprintf(). If the 2731 * return is greater than or equal to @size, the resulting 2732 * string is truncated. 2733 * 2734 * If you're not already dealing with a va_list consider using snprintf(). 2735 */ 2736 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2737 { 2738 unsigned long long num; 2739 char *str, *end; 2740 struct printf_spec spec = {0}; 2741 2742 /* Reject out-of-range values early. Large positive sizes are 2743 used for unknown buffer sizes. */ 2744 if (WARN_ON_ONCE(size > INT_MAX)) 2745 return 0; 2746 2747 str = buf; 2748 end = buf + size; 2749 2750 /* Make sure end is always >= buf */ 2751 if (end < buf) { 2752 end = ((void *)-1); 2753 size = end - buf; 2754 } 2755 2756 while (*fmt) { 2757 const char *old_fmt = fmt; 2758 int read = format_decode(fmt, &spec); 2759 2760 fmt += read; 2761 2762 switch (spec.type) { 2763 case FORMAT_TYPE_NONE: { 2764 int copy = read; 2765 if (str < end) { 2766 if (copy > end - str) 2767 copy = end - str; 2768 memcpy(str, old_fmt, copy); 2769 } 2770 str += read; 2771 break; 2772 } 2773 2774 case FORMAT_TYPE_WIDTH: 2775 set_field_width(&spec, va_arg(args, int)); 2776 break; 2777 2778 case FORMAT_TYPE_PRECISION: 2779 set_precision(&spec, va_arg(args, int)); 2780 break; 2781 2782 case FORMAT_TYPE_CHAR: { 2783 char c; 2784 2785 if (!(spec.flags & LEFT)) { 2786 while (--spec.field_width > 0) { 2787 if (str < end) 2788 *str = ' '; 2789 ++str; 2790 2791 } 2792 } 2793 c = (unsigned char) va_arg(args, int); 2794 if (str < end) 2795 *str = c; 2796 ++str; 2797 while (--spec.field_width > 0) { 2798 if (str < end) 2799 *str = ' '; 2800 ++str; 2801 } 2802 break; 2803 } 2804 2805 case FORMAT_TYPE_STR: 2806 str = string(str, end, va_arg(args, char *), spec); 2807 break; 2808 2809 case FORMAT_TYPE_PTR: 2810 str = pointer(fmt, str, end, va_arg(args, void *), 2811 spec); 2812 while (isalnum(*fmt)) 2813 fmt++; 2814 break; 2815 2816 case FORMAT_TYPE_PERCENT_CHAR: 2817 if (str < end) 2818 *str = '%'; 2819 ++str; 2820 break; 2821 2822 case FORMAT_TYPE_INVALID: 2823 /* 2824 * Presumably the arguments passed gcc's type 2825 * checking, but there is no safe or sane way 2826 * for us to continue parsing the format and 2827 * fetching from the va_list; the remaining 2828 * specifiers and arguments would be out of 2829 * sync. 2830 */ 2831 goto out; 2832 2833 default: 2834 switch (spec.type) { 2835 case FORMAT_TYPE_LONG_LONG: 2836 num = va_arg(args, long long); 2837 break; 2838 case FORMAT_TYPE_ULONG: 2839 num = va_arg(args, unsigned long); 2840 break; 2841 case FORMAT_TYPE_LONG: 2842 num = va_arg(args, long); 2843 break; 2844 case FORMAT_TYPE_SIZE_T: 2845 if (spec.flags & SIGN) 2846 num = va_arg(args, ssize_t); 2847 else 2848 num = va_arg(args, size_t); 2849 break; 2850 case FORMAT_TYPE_PTRDIFF: 2851 num = va_arg(args, ptrdiff_t); 2852 break; 2853 case FORMAT_TYPE_UBYTE: 2854 num = (unsigned char) va_arg(args, int); 2855 break; 2856 case FORMAT_TYPE_BYTE: 2857 num = (signed char) va_arg(args, int); 2858 break; 2859 case FORMAT_TYPE_USHORT: 2860 num = (unsigned short) va_arg(args, int); 2861 break; 2862 case FORMAT_TYPE_SHORT: 2863 num = (short) va_arg(args, int); 2864 break; 2865 case FORMAT_TYPE_INT: 2866 num = (int) va_arg(args, int); 2867 break; 2868 default: 2869 num = va_arg(args, unsigned int); 2870 } 2871 2872 str = number(str, end, num, spec); 2873 } 2874 } 2875 2876 out: 2877 if (size > 0) { 2878 if (str < end) 2879 *str = '\0'; 2880 else 2881 end[-1] = '\0'; 2882 } 2883 2884 /* the trailing null byte doesn't count towards the total */ 2885 return str-buf; 2886 2887 } 2888 EXPORT_SYMBOL(vsnprintf); 2889 2890 /** 2891 * vscnprintf - Format a string and place it in a buffer 2892 * @buf: The buffer to place the result into 2893 * @size: The size of the buffer, including the trailing null space 2894 * @fmt: The format string to use 2895 * @args: Arguments for the format string 2896 * 2897 * The return value is the number of characters which have been written into 2898 * the @buf not including the trailing '\0'. If @size is == 0 the function 2899 * returns 0. 2900 * 2901 * If you're not already dealing with a va_list consider using scnprintf(). 2902 * 2903 * See the vsnprintf() documentation for format string extensions over C99. 2904 */ 2905 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2906 { 2907 int i; 2908 2909 if (unlikely(!size)) 2910 return 0; 2911 2912 i = vsnprintf(buf, size, fmt, args); 2913 2914 if (likely(i < size)) 2915 return i; 2916 2917 return size - 1; 2918 } 2919 EXPORT_SYMBOL(vscnprintf); 2920 2921 /** 2922 * snprintf - Format a string and place it in a buffer 2923 * @buf: The buffer to place the result into 2924 * @size: The size of the buffer, including the trailing null space 2925 * @fmt: The format string to use 2926 * @...: Arguments for the format string 2927 * 2928 * The return value is the number of characters which would be 2929 * generated for the given input, excluding the trailing null, 2930 * as per ISO C99. If the return is greater than or equal to 2931 * @size, the resulting string is truncated. 2932 * 2933 * See the vsnprintf() documentation for format string extensions over C99. 2934 */ 2935 int snprintf(char *buf, size_t size, const char *fmt, ...) 2936 { 2937 va_list args; 2938 int i; 2939 2940 va_start(args, fmt); 2941 i = vsnprintf(buf, size, fmt, args); 2942 va_end(args); 2943 2944 return i; 2945 } 2946 EXPORT_SYMBOL(snprintf); 2947 2948 /** 2949 * scnprintf - Format a string and place it in a buffer 2950 * @buf: The buffer to place the result into 2951 * @size: The size of the buffer, including the trailing null space 2952 * @fmt: The format string to use 2953 * @...: Arguments for the format string 2954 * 2955 * The return value is the number of characters written into @buf not including 2956 * the trailing '\0'. If @size is == 0 the function returns 0. 2957 */ 2958 2959 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2960 { 2961 va_list args; 2962 int i; 2963 2964 va_start(args, fmt); 2965 i = vscnprintf(buf, size, fmt, args); 2966 va_end(args); 2967 2968 return i; 2969 } 2970 EXPORT_SYMBOL(scnprintf); 2971 2972 /** 2973 * vsprintf - Format a string and place it in a buffer 2974 * @buf: The buffer to place the result into 2975 * @fmt: The format string to use 2976 * @args: Arguments for the format string 2977 * 2978 * The function returns the number of characters written 2979 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2980 * buffer overflows. 2981 * 2982 * If you're not already dealing with a va_list consider using sprintf(). 2983 * 2984 * See the vsnprintf() documentation for format string extensions over C99. 2985 */ 2986 int vsprintf(char *buf, const char *fmt, va_list args) 2987 { 2988 return vsnprintf(buf, INT_MAX, fmt, args); 2989 } 2990 EXPORT_SYMBOL(vsprintf); 2991 2992 /** 2993 * sprintf - Format a string and place it in a buffer 2994 * @buf: The buffer to place the result into 2995 * @fmt: The format string to use 2996 * @...: Arguments for the format string 2997 * 2998 * The function returns the number of characters written 2999 * into @buf. Use snprintf() or scnprintf() in order to avoid 3000 * buffer overflows. 3001 * 3002 * See the vsnprintf() documentation for format string extensions over C99. 3003 */ 3004 int sprintf(char *buf, const char *fmt, ...) 3005 { 3006 va_list args; 3007 int i; 3008 3009 va_start(args, fmt); 3010 i = vsnprintf(buf, INT_MAX, fmt, args); 3011 va_end(args); 3012 3013 return i; 3014 } 3015 EXPORT_SYMBOL(sprintf); 3016 3017 #ifdef CONFIG_BINARY_PRINTF 3018 /* 3019 * bprintf service: 3020 * vbin_printf() - VA arguments to binary data 3021 * bstr_printf() - Binary data to text string 3022 */ 3023 3024 /** 3025 * vbin_printf - Parse a format string and place args' binary value in a buffer 3026 * @bin_buf: The buffer to place args' binary value 3027 * @size: The size of the buffer(by words(32bits), not characters) 3028 * @fmt: The format string to use 3029 * @args: Arguments for the format string 3030 * 3031 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3032 * is skipped. 3033 * 3034 * The return value is the number of words(32bits) which would be generated for 3035 * the given input. 3036 * 3037 * NOTE: 3038 * If the return value is greater than @size, the resulting bin_buf is NOT 3039 * valid for bstr_printf(). 3040 */ 3041 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 3042 { 3043 struct printf_spec spec = {0}; 3044 char *str, *end; 3045 int width; 3046 3047 str = (char *)bin_buf; 3048 end = (char *)(bin_buf + size); 3049 3050 #define save_arg(type) \ 3051 ({ \ 3052 unsigned long long value; \ 3053 if (sizeof(type) == 8) { \ 3054 unsigned long long val8; \ 3055 str = PTR_ALIGN(str, sizeof(u32)); \ 3056 val8 = va_arg(args, unsigned long long); \ 3057 if (str + sizeof(type) <= end) { \ 3058 *(u32 *)str = *(u32 *)&val8; \ 3059 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3060 } \ 3061 value = val8; \ 3062 } else { \ 3063 unsigned int val4; \ 3064 str = PTR_ALIGN(str, sizeof(type)); \ 3065 val4 = va_arg(args, int); \ 3066 if (str + sizeof(type) <= end) \ 3067 *(typeof(type) *)str = (type)(long)val4; \ 3068 value = (unsigned long long)val4; \ 3069 } \ 3070 str += sizeof(type); \ 3071 value; \ 3072 }) 3073 3074 while (*fmt) { 3075 int read = format_decode(fmt, &spec); 3076 3077 fmt += read; 3078 3079 switch (spec.type) { 3080 case FORMAT_TYPE_NONE: 3081 case FORMAT_TYPE_PERCENT_CHAR: 3082 break; 3083 case FORMAT_TYPE_INVALID: 3084 goto out; 3085 3086 case FORMAT_TYPE_WIDTH: 3087 case FORMAT_TYPE_PRECISION: 3088 width = (int)save_arg(int); 3089 /* Pointers may require the width */ 3090 if (*fmt == 'p') 3091 set_field_width(&spec, width); 3092 break; 3093 3094 case FORMAT_TYPE_CHAR: 3095 save_arg(char); 3096 break; 3097 3098 case FORMAT_TYPE_STR: { 3099 const char *save_str = va_arg(args, char *); 3100 const char *err_msg; 3101 size_t len; 3102 3103 err_msg = check_pointer_msg(save_str); 3104 if (err_msg) 3105 save_str = err_msg; 3106 3107 len = strlen(save_str) + 1; 3108 if (str + len < end) 3109 memcpy(str, save_str, len); 3110 str += len; 3111 break; 3112 } 3113 3114 case FORMAT_TYPE_PTR: 3115 /* Dereferenced pointers must be done now */ 3116 switch (*fmt) { 3117 /* Dereference of functions is still OK */ 3118 case 'S': 3119 case 's': 3120 case 'x': 3121 case 'K': 3122 case 'e': 3123 save_arg(void *); 3124 break; 3125 default: 3126 if (!isalnum(*fmt)) { 3127 save_arg(void *); 3128 break; 3129 } 3130 str = pointer(fmt, str, end, va_arg(args, void *), 3131 spec); 3132 if (str + 1 < end) 3133 *str++ = '\0'; 3134 else 3135 end[-1] = '\0'; /* Must be nul terminated */ 3136 } 3137 /* skip all alphanumeric pointer suffixes */ 3138 while (isalnum(*fmt)) 3139 fmt++; 3140 break; 3141 3142 default: 3143 switch (spec.type) { 3144 3145 case FORMAT_TYPE_LONG_LONG: 3146 save_arg(long long); 3147 break; 3148 case FORMAT_TYPE_ULONG: 3149 case FORMAT_TYPE_LONG: 3150 save_arg(unsigned long); 3151 break; 3152 case FORMAT_TYPE_SIZE_T: 3153 save_arg(size_t); 3154 break; 3155 case FORMAT_TYPE_PTRDIFF: 3156 save_arg(ptrdiff_t); 3157 break; 3158 case FORMAT_TYPE_UBYTE: 3159 case FORMAT_TYPE_BYTE: 3160 save_arg(char); 3161 break; 3162 case FORMAT_TYPE_USHORT: 3163 case FORMAT_TYPE_SHORT: 3164 save_arg(short); 3165 break; 3166 default: 3167 save_arg(int); 3168 } 3169 } 3170 } 3171 3172 out: 3173 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3174 #undef save_arg 3175 } 3176 EXPORT_SYMBOL_GPL(vbin_printf); 3177 3178 /** 3179 * bstr_printf - Format a string from binary arguments and place it in a buffer 3180 * @buf: The buffer to place the result into 3181 * @size: The size of the buffer, including the trailing null space 3182 * @fmt: The format string to use 3183 * @bin_buf: Binary arguments for the format string 3184 * 3185 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3186 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3187 * a binary buffer that generated by vbin_printf. 3188 * 3189 * The format follows C99 vsnprintf, but has some extensions: 3190 * see vsnprintf comment for details. 3191 * 3192 * The return value is the number of characters which would 3193 * be generated for the given input, excluding the trailing 3194 * '\0', as per ISO C99. If you want to have the exact 3195 * number of characters written into @buf as return value 3196 * (not including the trailing '\0'), use vscnprintf(). If the 3197 * return is greater than or equal to @size, the resulting 3198 * string is truncated. 3199 */ 3200 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 3201 { 3202 struct printf_spec spec = {0}; 3203 char *str, *end; 3204 const char *args = (const char *)bin_buf; 3205 3206 if (WARN_ON_ONCE(size > INT_MAX)) 3207 return 0; 3208 3209 str = buf; 3210 end = buf + size; 3211 3212 #define get_arg(type) \ 3213 ({ \ 3214 typeof(type) value; \ 3215 if (sizeof(type) == 8) { \ 3216 args = PTR_ALIGN(args, sizeof(u32)); \ 3217 *(u32 *)&value = *(u32 *)args; \ 3218 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3219 } else { \ 3220 args = PTR_ALIGN(args, sizeof(type)); \ 3221 value = *(typeof(type) *)args; \ 3222 } \ 3223 args += sizeof(type); \ 3224 value; \ 3225 }) 3226 3227 /* Make sure end is always >= buf */ 3228 if (end < buf) { 3229 end = ((void *)-1); 3230 size = end - buf; 3231 } 3232 3233 while (*fmt) { 3234 const char *old_fmt = fmt; 3235 int read = format_decode(fmt, &spec); 3236 3237 fmt += read; 3238 3239 switch (spec.type) { 3240 case FORMAT_TYPE_NONE: { 3241 int copy = read; 3242 if (str < end) { 3243 if (copy > end - str) 3244 copy = end - str; 3245 memcpy(str, old_fmt, copy); 3246 } 3247 str += read; 3248 break; 3249 } 3250 3251 case FORMAT_TYPE_WIDTH: 3252 set_field_width(&spec, get_arg(int)); 3253 break; 3254 3255 case FORMAT_TYPE_PRECISION: 3256 set_precision(&spec, get_arg(int)); 3257 break; 3258 3259 case FORMAT_TYPE_CHAR: { 3260 char c; 3261 3262 if (!(spec.flags & LEFT)) { 3263 while (--spec.field_width > 0) { 3264 if (str < end) 3265 *str = ' '; 3266 ++str; 3267 } 3268 } 3269 c = (unsigned char) get_arg(char); 3270 if (str < end) 3271 *str = c; 3272 ++str; 3273 while (--spec.field_width > 0) { 3274 if (str < end) 3275 *str = ' '; 3276 ++str; 3277 } 3278 break; 3279 } 3280 3281 case FORMAT_TYPE_STR: { 3282 const char *str_arg = args; 3283 args += strlen(str_arg) + 1; 3284 str = string(str, end, (char *)str_arg, spec); 3285 break; 3286 } 3287 3288 case FORMAT_TYPE_PTR: { 3289 bool process = false; 3290 int copy, len; 3291 /* Non function dereferences were already done */ 3292 switch (*fmt) { 3293 case 'S': 3294 case 's': 3295 case 'x': 3296 case 'K': 3297 case 'e': 3298 process = true; 3299 break; 3300 default: 3301 if (!isalnum(*fmt)) { 3302 process = true; 3303 break; 3304 } 3305 /* Pointer dereference was already processed */ 3306 if (str < end) { 3307 len = copy = strlen(args); 3308 if (copy > end - str) 3309 copy = end - str; 3310 memcpy(str, args, copy); 3311 str += len; 3312 args += len + 1; 3313 } 3314 } 3315 if (process) 3316 str = pointer(fmt, str, end, get_arg(void *), spec); 3317 3318 while (isalnum(*fmt)) 3319 fmt++; 3320 break; 3321 } 3322 3323 case FORMAT_TYPE_PERCENT_CHAR: 3324 if (str < end) 3325 *str = '%'; 3326 ++str; 3327 break; 3328 3329 case FORMAT_TYPE_INVALID: 3330 goto out; 3331 3332 default: { 3333 unsigned long long num; 3334 3335 switch (spec.type) { 3336 3337 case FORMAT_TYPE_LONG_LONG: 3338 num = get_arg(long long); 3339 break; 3340 case FORMAT_TYPE_ULONG: 3341 case FORMAT_TYPE_LONG: 3342 num = get_arg(unsigned long); 3343 break; 3344 case FORMAT_TYPE_SIZE_T: 3345 num = get_arg(size_t); 3346 break; 3347 case FORMAT_TYPE_PTRDIFF: 3348 num = get_arg(ptrdiff_t); 3349 break; 3350 case FORMAT_TYPE_UBYTE: 3351 num = get_arg(unsigned char); 3352 break; 3353 case FORMAT_TYPE_BYTE: 3354 num = get_arg(signed char); 3355 break; 3356 case FORMAT_TYPE_USHORT: 3357 num = get_arg(unsigned short); 3358 break; 3359 case FORMAT_TYPE_SHORT: 3360 num = get_arg(short); 3361 break; 3362 case FORMAT_TYPE_UINT: 3363 num = get_arg(unsigned int); 3364 break; 3365 default: 3366 num = get_arg(int); 3367 } 3368 3369 str = number(str, end, num, spec); 3370 } /* default: */ 3371 } /* switch(spec.type) */ 3372 } /* while(*fmt) */ 3373 3374 out: 3375 if (size > 0) { 3376 if (str < end) 3377 *str = '\0'; 3378 else 3379 end[-1] = '\0'; 3380 } 3381 3382 #undef get_arg 3383 3384 /* the trailing null byte doesn't count towards the total */ 3385 return str - buf; 3386 } 3387 EXPORT_SYMBOL_GPL(bstr_printf); 3388 3389 /** 3390 * bprintf - Parse a format string and place args' binary value in a buffer 3391 * @bin_buf: The buffer to place args' binary value 3392 * @size: The size of the buffer(by words(32bits), not characters) 3393 * @fmt: The format string to use 3394 * @...: Arguments for the format string 3395 * 3396 * The function returns the number of words(u32) written 3397 * into @bin_buf. 3398 */ 3399 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 3400 { 3401 va_list args; 3402 int ret; 3403 3404 va_start(args, fmt); 3405 ret = vbin_printf(bin_buf, size, fmt, args); 3406 va_end(args); 3407 3408 return ret; 3409 } 3410 EXPORT_SYMBOL_GPL(bprintf); 3411 3412 #endif /* CONFIG_BINARY_PRINTF */ 3413 3414 /** 3415 * vsscanf - Unformat a buffer into a list of arguments 3416 * @buf: input buffer 3417 * @fmt: format of buffer 3418 * @args: arguments 3419 */ 3420 int vsscanf(const char *buf, const char *fmt, va_list args) 3421 { 3422 const char *str = buf; 3423 char *next; 3424 char digit; 3425 int num = 0; 3426 u8 qualifier; 3427 unsigned int base; 3428 union { 3429 long long s; 3430 unsigned long long u; 3431 } val; 3432 s16 field_width; 3433 bool is_sign; 3434 3435 while (*fmt) { 3436 /* skip any white space in format */ 3437 /* white space in format matches any amount of 3438 * white space, including none, in the input. 3439 */ 3440 if (isspace(*fmt)) { 3441 fmt = skip_spaces(++fmt); 3442 str = skip_spaces(str); 3443 } 3444 3445 /* anything that is not a conversion must match exactly */ 3446 if (*fmt != '%' && *fmt) { 3447 if (*fmt++ != *str++) 3448 break; 3449 continue; 3450 } 3451 3452 if (!*fmt) 3453 break; 3454 ++fmt; 3455 3456 /* skip this conversion. 3457 * advance both strings to next white space 3458 */ 3459 if (*fmt == '*') { 3460 if (!*str) 3461 break; 3462 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3463 /* '%*[' not yet supported, invalid format */ 3464 if (*fmt == '[') 3465 return num; 3466 fmt++; 3467 } 3468 while (!isspace(*str) && *str) 3469 str++; 3470 continue; 3471 } 3472 3473 /* get field width */ 3474 field_width = -1; 3475 if (isdigit(*fmt)) { 3476 field_width = skip_atoi(&fmt); 3477 if (field_width <= 0) 3478 break; 3479 } 3480 3481 /* get conversion qualifier */ 3482 qualifier = -1; 3483 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3484 *fmt == 'z') { 3485 qualifier = *fmt++; 3486 if (unlikely(qualifier == *fmt)) { 3487 if (qualifier == 'h') { 3488 qualifier = 'H'; 3489 fmt++; 3490 } else if (qualifier == 'l') { 3491 qualifier = 'L'; 3492 fmt++; 3493 } 3494 } 3495 } 3496 3497 if (!*fmt) 3498 break; 3499 3500 if (*fmt == 'n') { 3501 /* return number of characters read so far */ 3502 *va_arg(args, int *) = str - buf; 3503 ++fmt; 3504 continue; 3505 } 3506 3507 if (!*str) 3508 break; 3509 3510 base = 10; 3511 is_sign = false; 3512 3513 switch (*fmt++) { 3514 case 'c': 3515 { 3516 char *s = (char *)va_arg(args, char*); 3517 if (field_width == -1) 3518 field_width = 1; 3519 do { 3520 *s++ = *str++; 3521 } while (--field_width > 0 && *str); 3522 num++; 3523 } 3524 continue; 3525 case 's': 3526 { 3527 char *s = (char *)va_arg(args, char *); 3528 if (field_width == -1) 3529 field_width = SHRT_MAX; 3530 /* first, skip leading white space in buffer */ 3531 str = skip_spaces(str); 3532 3533 /* now copy until next white space */ 3534 while (*str && !isspace(*str) && field_width--) 3535 *s++ = *str++; 3536 *s = '\0'; 3537 num++; 3538 } 3539 continue; 3540 /* 3541 * Warning: This implementation of the '[' conversion specifier 3542 * deviates from its glibc counterpart in the following ways: 3543 * (1) It does NOT support ranges i.e. '-' is NOT a special 3544 * character 3545 * (2) It cannot match the closing bracket ']' itself 3546 * (3) A field width is required 3547 * (4) '%*[' (discard matching input) is currently not supported 3548 * 3549 * Example usage: 3550 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3551 * buf1, buf2, buf3); 3552 * if (ret < 3) 3553 * // etc.. 3554 */ 3555 case '[': 3556 { 3557 char *s = (char *)va_arg(args, char *); 3558 DECLARE_BITMAP(set, 256) = {0}; 3559 unsigned int len = 0; 3560 bool negate = (*fmt == '^'); 3561 3562 /* field width is required */ 3563 if (field_width == -1) 3564 return num; 3565 3566 if (negate) 3567 ++fmt; 3568 3569 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3570 __set_bit((u8)*fmt, set); 3571 3572 /* no ']' or no character set found */ 3573 if (!*fmt || !len) 3574 return num; 3575 ++fmt; 3576 3577 if (negate) { 3578 bitmap_complement(set, set, 256); 3579 /* exclude null '\0' byte */ 3580 __clear_bit(0, set); 3581 } 3582 3583 /* match must be non-empty */ 3584 if (!test_bit((u8)*str, set)) 3585 return num; 3586 3587 while (test_bit((u8)*str, set) && field_width--) 3588 *s++ = *str++; 3589 *s = '\0'; 3590 ++num; 3591 } 3592 continue; 3593 case 'o': 3594 base = 8; 3595 break; 3596 case 'x': 3597 case 'X': 3598 base = 16; 3599 break; 3600 case 'i': 3601 base = 0; 3602 fallthrough; 3603 case 'd': 3604 is_sign = true; 3605 fallthrough; 3606 case 'u': 3607 break; 3608 case '%': 3609 /* looking for '%' in str */ 3610 if (*str++ != '%') 3611 return num; 3612 continue; 3613 default: 3614 /* invalid format; stop here */ 3615 return num; 3616 } 3617 3618 /* have some sort of integer conversion. 3619 * first, skip white space in buffer. 3620 */ 3621 str = skip_spaces(str); 3622 3623 digit = *str; 3624 if (is_sign && digit == '-') { 3625 if (field_width == 1) 3626 break; 3627 3628 digit = *(str + 1); 3629 } 3630 3631 if (!digit 3632 || (base == 16 && !isxdigit(digit)) 3633 || (base == 10 && !isdigit(digit)) 3634 || (base == 8 && (!isdigit(digit) || digit > '7')) 3635 || (base == 0 && !isdigit(digit))) 3636 break; 3637 3638 if (is_sign) 3639 val.s = simple_strntoll(str, 3640 field_width >= 0 ? field_width : INT_MAX, 3641 &next, base); 3642 else 3643 val.u = simple_strntoull(str, 3644 field_width >= 0 ? field_width : INT_MAX, 3645 &next, base); 3646 3647 switch (qualifier) { 3648 case 'H': /* that's 'hh' in format */ 3649 if (is_sign) 3650 *va_arg(args, signed char *) = val.s; 3651 else 3652 *va_arg(args, unsigned char *) = val.u; 3653 break; 3654 case 'h': 3655 if (is_sign) 3656 *va_arg(args, short *) = val.s; 3657 else 3658 *va_arg(args, unsigned short *) = val.u; 3659 break; 3660 case 'l': 3661 if (is_sign) 3662 *va_arg(args, long *) = val.s; 3663 else 3664 *va_arg(args, unsigned long *) = val.u; 3665 break; 3666 case 'L': 3667 if (is_sign) 3668 *va_arg(args, long long *) = val.s; 3669 else 3670 *va_arg(args, unsigned long long *) = val.u; 3671 break; 3672 case 'z': 3673 *va_arg(args, size_t *) = val.u; 3674 break; 3675 default: 3676 if (is_sign) 3677 *va_arg(args, int *) = val.s; 3678 else 3679 *va_arg(args, unsigned int *) = val.u; 3680 break; 3681 } 3682 num++; 3683 3684 if (!next) 3685 break; 3686 str = next; 3687 } 3688 3689 return num; 3690 } 3691 EXPORT_SYMBOL(vsscanf); 3692 3693 /** 3694 * sscanf - Unformat a buffer into a list of arguments 3695 * @buf: input buffer 3696 * @fmt: formatting of buffer 3697 * @...: resulting arguments 3698 */ 3699 int sscanf(const char *buf, const char *fmt, ...) 3700 { 3701 va_list args; 3702 int i; 3703 3704 va_start(args, fmt); 3705 i = vsscanf(buf, fmt, args); 3706 va_end(args); 3707 3708 return i; 3709 } 3710 EXPORT_SYMBOL(sscanf); 3711