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vsprintf.c
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linux-6.19.14/lib/vsprintf.c
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/sprintf.h> 38#include <linux/time.h> 39#include <linux/uuid.h> 40#include <linux/of.h> 41#include <net/addrconf.h> 42#include <linux/siphash.h> 43#include <linux/compiler.h> 44#include <linux/property.h> 45#include <linux/notifier.h> 46#ifdef CONFIG_BLOCK 47#include <linux/blkdev.h> 48#endif 49 50#include "../mm/internal.h" /* For the trace_print_flags arrays */ 51 52#include <asm/page.h> /* for PAGE_SIZE */ 53#include <asm/byteorder.h> /* cpu_to_le16 */ 54#include <linux/unaligned.h> 55 56#include <linux/string_helpers.h> 57#include "kstrtox.h" 58 59/* Disable pointer hashing if requested */ 60bool no_hash_pointers __ro_after_init; 61EXPORT_SYMBOL_GPL(no_hash_pointers); 62 63/* 64 * Hashed pointers policy selected by "hash_pointers=..." boot param 65 * 66 * `auto` - Hashed pointers enabled unless disabled by slub_debug_enabled=true 67 * `always` - Hashed pointers enabled unconditionally 68 * `never` - Hashed pointers disabled unconditionally 69 */ 70enum hash_pointers_policy { 71 HASH_PTR_AUTO = 0, 72 HASH_PTR_ALWAYS, 73 HASH_PTR_NEVER 74}; 75static enum hash_pointers_policy hash_pointers_mode __initdata; 76 77noinline 78static unsigned long long simple_strntoull(const char *startp, char **endp, unsigned int base, size_t max_chars) 79{ 80 const char *cp; 81 unsigned long long result = 0ULL; 82 size_t prefix_chars; 83 unsigned int rv; 84 85 cp = _parse_integer_fixup_radix(startp, &base); 86 prefix_chars = cp - startp; 87 if (prefix_chars < max_chars) { 88 rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); 89 /* FIXME */ 90 cp += (rv & ~KSTRTOX_OVERFLOW); 91 } else { 92 /* Field too short for prefix + digit, skip over without converting */ 93 cp = startp + max_chars; 94 } 95 96 if (endp) 97 *endp = (char *)cp; 98 99 return result; 100} 101 102/** 103 * simple_strtoull - convert a string to an unsigned long long 104 * @cp: The start of the string 105 * @endp: A pointer to the end of the parsed string will be placed here 106 * @base: The number base to use 107 * 108 * This function has caveats. Please use kstrtoull instead. 109 */ 110noinline 111unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 112{ 113 return simple_strntoull(cp, endp, base, INT_MAX); 114} 115EXPORT_SYMBOL(simple_strtoull); 116 117/** 118 * simple_strtoul - convert a string to an unsigned long 119 * @cp: The start of the string 120 * @endp: A pointer to the end of the parsed string will be placed here 121 * @base: The number base to use 122 * 123 * This function has caveats. Please use kstrtoul instead. 124 */ 125unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 126{ 127 return simple_strtoull(cp, endp, base); 128} 129EXPORT_SYMBOL(simple_strtoul); 130 131unsigned long simple_strntoul(const char *cp, char **endp, unsigned int base, 132 size_t max_chars) 133{ 134 return simple_strntoull(cp, endp, base, max_chars); 135} 136EXPORT_SYMBOL(simple_strntoul); 137 138/** 139 * simple_strtol - convert a string to a signed long 140 * @cp: The start of the string 141 * @endp: A pointer to the end of the parsed string will be placed here 142 * @base: The number base to use 143 * 144 * This function has caveats. Please use kstrtol instead. 145 */ 146long simple_strtol(const char *cp, char **endp, unsigned int base) 147{ 148 if (*cp == '-') 149 return -simple_strtoul(cp + 1, endp, base); 150 151 return simple_strtoul(cp, endp, base); 152} 153EXPORT_SYMBOL(simple_strtol); 154 155noinline 156static long long simple_strntoll(const char *cp, char **endp, unsigned int base, size_t max_chars) 157{ 158 /* 159 * simple_strntoull() safely handles receiving max_chars==0 in the 160 * case cp[0] == '-' && max_chars == 1. 161 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 162 * and the content of *cp is irrelevant. 163 */ 164 if (*cp == '-' && max_chars > 0) 165 return -simple_strntoull(cp + 1, endp, base, max_chars - 1); 166 167 return simple_strntoull(cp, endp, base, max_chars); 168} 169 170/** 171 * simple_strtoll - convert a string to a signed long long 172 * @cp: The start of the string 173 * @endp: A pointer to the end of the parsed string will be placed here 174 * @base: The number base to use 175 * 176 * This function has caveats. Please use kstrtoll instead. 177 */ 178long long simple_strtoll(const char *cp, char **endp, unsigned int base) 179{ 180 return simple_strntoll(cp, endp, base, INT_MAX); 181} 182EXPORT_SYMBOL(simple_strtoll); 183 184static inline int skip_atoi(const char **s) 185{ 186 int i = 0; 187 188 do { 189 i = i*10 + *((*s)++) - '0'; 190 } while (isdigit(**s)); 191 192 return i; 193} 194 195/* 196 * Decimal conversion is by far the most typical, and is used for 197 * /proc and /sys data. This directly impacts e.g. top performance 198 * with many processes running. We optimize it for speed by emitting 199 * two characters at a time, using a 200 byte lookup table. This 200 * roughly halves the number of multiplications compared to computing 201 * the digits one at a time. Implementation strongly inspired by the 202 * previous version, which in turn used ideas described at 203 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 204 * from the author, Douglas W. Jones). 205 * 206 * It turns out there is precisely one 26 bit fixed-point 207 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 208 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 209 * range happens to be somewhat larger (x <= 1073741898), but that's 210 * irrelevant for our purpose. 211 * 212 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 213 * need a 32x32->64 bit multiply, so we simply use the same constant. 214 * 215 * For dividing a number in the range [100, 10^4-1] by 100, there are 216 * several options. The simplest is (x * 0x147b) >> 19, which is valid 217 * for all x <= 43698. 218 */ 219 220static const u16 decpair[100] = { 221#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 222 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 223 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 224 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 225 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 226 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 227 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 228 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 229 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 230 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 231 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 232#undef _ 233}; 234 235/* 236 * This will print a single '0' even if r == 0, since we would 237 * immediately jump to out_r where two 0s would be written but only 238 * one of them accounted for in buf. This is needed by ip4_string 239 * below. All other callers pass a non-zero value of r. 240*/ 241static noinline_for_stack 242char *put_dec_trunc8(char *buf, unsigned r) 243{ 244 unsigned q; 245 246 /* 1 <= r < 10^8 */ 247 if (r < 100) 248 goto out_r; 249 250 /* 100 <= r < 10^8 */ 251 q = (r * (u64)0x28f5c29) >> 32; 252 *((u16 *)buf) = decpair[r - 100*q]; 253 buf += 2; 254 255 /* 1 <= q < 10^6 */ 256 if (q < 100) 257 goto out_q; 258 259 /* 100 <= q < 10^6 */ 260 r = (q * (u64)0x28f5c29) >> 32; 261 *((u16 *)buf) = decpair[q - 100*r]; 262 buf += 2; 263 264 /* 1 <= r < 10^4 */ 265 if (r < 100) 266 goto out_r; 267 268 /* 100 <= r < 10^4 */ 269 q = (r * 0x147b) >> 19; 270 *((u16 *)buf) = decpair[r - 100*q]; 271 buf += 2; 272out_q: 273 /* 1 <= q < 100 */ 274 r = q; 275out_r: 276 /* 1 <= r < 100 */ 277 *((u16 *)buf) = decpair[r]; 278 buf += r < 10 ? 1 : 2; 279 return buf; 280} 281 282#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 283static noinline_for_stack 284char *put_dec_full8(char *buf, unsigned r) 285{ 286 unsigned q; 287 288 /* 0 <= r < 10^8 */ 289 q = (r * (u64)0x28f5c29) >> 32; 290 *((u16 *)buf) = decpair[r - 100*q]; 291 buf += 2; 292 293 /* 0 <= q < 10^6 */ 294 r = (q * (u64)0x28f5c29) >> 32; 295 *((u16 *)buf) = decpair[q - 100*r]; 296 buf += 2; 297 298 /* 0 <= r < 10^4 */ 299 q = (r * 0x147b) >> 19; 300 *((u16 *)buf) = decpair[r - 100*q]; 301 buf += 2; 302 303 /* 0 <= q < 100 */ 304 *((u16 *)buf) = decpair[q]; 305 buf += 2; 306 return buf; 307} 308 309static noinline_for_stack 310char *put_dec(char *buf, unsigned long long n) 311{ 312 if (n >= 100*1000*1000) 313 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 314 /* 1 <= n <= 1.6e11 */ 315 if (n >= 100*1000*1000) 316 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 317 /* 1 <= n < 1e8 */ 318 return put_dec_trunc8(buf, n); 319} 320 321#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 322 323static void 324put_dec_full4(char *buf, unsigned r) 325{ 326 unsigned q; 327 328 /* 0 <= r < 10^4 */ 329 q = (r * 0x147b) >> 19; 330 *((u16 *)buf) = decpair[r - 100*q]; 331 buf += 2; 332 /* 0 <= q < 100 */ 333 *((u16 *)buf) = decpair[q]; 334} 335 336/* 337 * Call put_dec_full4 on x % 10000, return x / 10000. 338 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 339 * holds for all x < 1,128,869,999. The largest value this 340 * helper will ever be asked to convert is 1,125,520,955. 341 * (second call in the put_dec code, assuming n is all-ones). 342 */ 343static noinline_for_stack 344unsigned put_dec_helper4(char *buf, unsigned x) 345{ 346 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 347 348 put_dec_full4(buf, x - q * 10000); 349 return q; 350} 351 352/* Based on code by Douglas W. Jones found at 353 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 354 * (with permission from the author). 355 * Performs no 64-bit division and hence should be fast on 32-bit machines. 356 */ 357static 358char *put_dec(char *buf, unsigned long long n) 359{ 360 uint32_t d3, d2, d1, q, h; 361 362 if (n < 100*1000*1000) 363 return put_dec_trunc8(buf, n); 364 365 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 366 h = (n >> 32); 367 d2 = (h ) & 0xffff; 368 d3 = (h >> 16); /* implicit "& 0xffff" */ 369 370 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 371 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 372 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 373 q = put_dec_helper4(buf, q); 374 375 q += 7671 * d3 + 9496 * d2 + 6 * d1; 376 q = put_dec_helper4(buf+4, q); 377 378 q += 4749 * d3 + 42 * d2; 379 q = put_dec_helper4(buf+8, q); 380 381 q += 281 * d3; 382 buf += 12; 383 if (q) 384 buf = put_dec_trunc8(buf, q); 385 else while (buf[-1] == '0') 386 --buf; 387 388 return buf; 389} 390 391#endif 392 393/* 394 * Convert passed number to decimal string. 395 * Returns the length of string. On buffer overflow, returns 0. 396 * 397 * If speed is not important, use snprintf(). It's easy to read the code. 398 */ 399int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 400{ 401 /* put_dec requires 2-byte alignment of the buffer. */ 402 char tmp[sizeof(num) * 3] __aligned(2); 403 int idx, len; 404 405 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 406 if (num <= 9) { 407 tmp[0] = '0' + num; 408 len = 1; 409 } else { 410 len = put_dec(tmp, num) - tmp; 411 } 412 413 if (len > size || width > size) 414 return 0; 415 416 if (width > len) { 417 width = width - len; 418 for (idx = 0; idx < width; idx++) 419 buf[idx] = ' '; 420 } else { 421 width = 0; 422 } 423 424 for (idx = 0; idx < len; ++idx) 425 buf[idx + width] = tmp[len - idx - 1]; 426 427 return len + width; 428} 429 430#define SIGN 1 /* unsigned/signed */ 431#define LEFT 2 /* left justified */ 432#define PLUS 4 /* show plus */ 433#define SPACE 8 /* space if plus */ 434#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 435#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 436#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 437 438static_assert(ZEROPAD == ('0' - ' ')); 439static_assert(SMALL == ('a' ^ 'A')); 440 441enum format_state { 442 FORMAT_STATE_NONE, /* Just a string part */ 443 FORMAT_STATE_NUM, 444 FORMAT_STATE_WIDTH, 445 FORMAT_STATE_PRECISION, 446 FORMAT_STATE_CHAR, 447 FORMAT_STATE_STR, 448 FORMAT_STATE_PTR, 449 FORMAT_STATE_PERCENT_CHAR, 450 FORMAT_STATE_INVALID, 451}; 452 453struct printf_spec { 454 unsigned char flags; /* flags to number() */ 455 unsigned char base; /* number base, 8, 10 or 16 only */ 456 short precision; /* # of digits/chars */ 457 int field_width; /* width of output field */ 458} __packed; 459static_assert(sizeof(struct printf_spec) == 8); 460 461#define FIELD_WIDTH_MAX ((1 << 23) - 1) 462#define PRECISION_MAX ((1 << 15) - 1) 463 464static noinline_for_stack 465char *number(char *buf, char *end, unsigned long long num, 466 struct printf_spec spec) 467{ 468 /* put_dec requires 2-byte alignment of the buffer. */ 469 char tmp[3 * sizeof(num)] __aligned(2); 470 char sign; 471 char locase; 472 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 473 int i; 474 bool is_zero = num == 0LL; 475 int field_width = spec.field_width; 476 int precision = spec.precision; 477 478 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 479 * produces same digits or (maybe lowercased) letters */ 480 locase = (spec.flags & SMALL); 481 if (spec.flags & LEFT) 482 spec.flags &= ~ZEROPAD; 483 sign = 0; 484 if (spec.flags & SIGN) { 485 if ((signed long long)num < 0) { 486 sign = '-'; 487 num = -(signed long long)num; 488 field_width--; 489 } else if (spec.flags & PLUS) { 490 sign = '+'; 491 field_width--; 492 } else if (spec.flags & SPACE) { 493 sign = ' '; 494 field_width--; 495 } 496 } 497 if (need_pfx) { 498 if (spec.base == 16) 499 field_width -= 2; 500 else if (!is_zero) 501 field_width--; 502 } 503 504 /* generate full string in tmp[], in reverse order */ 505 i = 0; 506 if (num < spec.base) 507 tmp[i++] = hex_asc_upper[num] | locase; 508 else if (spec.base != 10) { /* 8 or 16 */ 509 int mask = spec.base - 1; 510 int shift = 3; 511 512 if (spec.base == 16) 513 shift = 4; 514 do { 515 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 516 num >>= shift; 517 } while (num); 518 } else { /* base 10 */ 519 i = put_dec(tmp, num) - tmp; 520 } 521 522 /* printing 100 using %2d gives "100", not "00" */ 523 if (i > precision) 524 precision = i; 525 /* leading space padding */ 526 field_width -= precision; 527 if (!(spec.flags & (ZEROPAD | LEFT))) { 528 while (--field_width >= 0) { 529 if (buf < end) 530 *buf = ' '; 531 ++buf; 532 } 533 } 534 /* sign */ 535 if (sign) { 536 if (buf < end) 537 *buf = sign; 538 ++buf; 539 } 540 /* "0x" / "0" prefix */ 541 if (need_pfx) { 542 if (spec.base == 16 || !is_zero) { 543 if (buf < end) 544 *buf = '0'; 545 ++buf; 546 } 547 if (spec.base == 16) { 548 if (buf < end) 549 *buf = ('X' | locase); 550 ++buf; 551 } 552 } 553 /* zero or space padding */ 554 if (!(spec.flags & LEFT)) { 555 char c = ' ' + (spec.flags & ZEROPAD); 556 557 while (--field_width >= 0) { 558 if (buf < end) 559 *buf = c; 560 ++buf; 561 } 562 } 563 /* hmm even more zero padding? */ 564 while (i <= --precision) { 565 if (buf < end) 566 *buf = '0'; 567 ++buf; 568 } 569 /* actual digits of result */ 570 while (--i >= 0) { 571 if (buf < end) 572 *buf = tmp[i]; 573 ++buf; 574 } 575 /* trailing space padding */ 576 while (--field_width >= 0) { 577 if (buf < end) 578 *buf = ' '; 579 ++buf; 580 } 581 582 return buf; 583} 584 585#define special_hex_spec(size) \ 586(struct printf_spec) { \ 587 .field_width = 2 + 2 * (size), /* 0x + hex */ \ 588 .flags = SPECIAL | SMALL | ZEROPAD, \ 589 .base = 16, \ 590 .precision = -1, \ 591} 592 593static noinline_for_stack 594char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 595{ 596 return number(buf, end, num, special_hex_spec(size)); 597} 598 599static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 600{ 601 size_t size; 602 if (buf >= end) /* nowhere to put anything */ 603 return; 604 size = end - buf; 605 if (size <= spaces) { 606 memset(buf, ' ', size); 607 return; 608 } 609 if (len) { 610 if (len > size - spaces) 611 len = size - spaces; 612 memmove(buf + spaces, buf, len); 613 } 614 memset(buf, ' ', spaces); 615} 616 617/* 618 * Handle field width padding for a string. 619 * @buf: current buffer position 620 * @n: length of string 621 * @end: end of output buffer 622 * @spec: for field width and flags 623 * Returns: new buffer position after padding. 624 */ 625static noinline_for_stack 626char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 627{ 628 unsigned spaces; 629 630 if (likely(n >= spec.field_width)) 631 return buf; 632 /* we want to pad the sucker */ 633 spaces = spec.field_width - n; 634 if (!(spec.flags & LEFT)) { 635 move_right(buf - n, end, n, spaces); 636 return buf + spaces; 637 } 638 while (spaces--) { 639 if (buf < end) 640 *buf = ' '; 641 ++buf; 642 } 643 return buf; 644} 645 646/* Handle string from a well known address. */ 647static char *string_nocheck(char *buf, char *end, const char *s, 648 struct printf_spec spec) 649{ 650 int len = 0; 651 int lim = spec.precision; 652 653 while (lim--) { 654 char c = *s++; 655 if (!c) 656 break; 657 if (buf < end) 658 *buf = c; 659 ++buf; 660 ++len; 661 } 662 return widen_string(buf, len, end, spec); 663} 664 665static char *err_ptr(char *buf, char *end, void *ptr, 666 struct printf_spec spec) 667{ 668 int err = PTR_ERR(ptr); 669 const char *sym = errname(err); 670 671 if (sym) 672 return string_nocheck(buf, end, sym, spec); 673 674 /* 675 * Somebody passed ERR_PTR(-1234) or some other non-existing 676 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 677 * printing it as its decimal representation. 678 */ 679 spec.flags |= SIGN; 680 spec.base = 10; 681 return number(buf, end, err, spec); 682} 683 684/* Be careful: error messages must fit into the given buffer. */ 685static char *error_string(char *buf, char *end, const char *s, 686 struct printf_spec spec) 687{ 688 /* 689 * Hard limit to avoid a completely insane messages. It actually 690 * works pretty well because most error messages are in 691 * the many pointer format modifiers. 692 */ 693 if (spec.precision == -1) 694 spec.precision = 2 * sizeof(void *); 695 696 return string_nocheck(buf, end, s, spec); 697} 698 699/* 700 * Do not call any complex external code here. Nested printk()/vsprintf() 701 * might cause infinite loops. Failures might break printk() and would 702 * be hard to debug. 703 */ 704static const char *check_pointer_msg(const void *ptr) 705{ 706 if (!ptr) 707 return "(null)"; 708 709 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 710 return "(efault)"; 711 712 return NULL; 713} 714 715static int check_pointer(char **buf, char *end, const void *ptr, 716 struct printf_spec spec) 717{ 718 const char *err_msg; 719 720 err_msg = check_pointer_msg(ptr); 721 if (err_msg) { 722 *buf = error_string(*buf, end, err_msg, spec); 723 return -EFAULT; 724 } 725 726 return 0; 727} 728 729static noinline_for_stack 730char *string(char *buf, char *end, const char *s, 731 struct printf_spec spec) 732{ 733 if (check_pointer(&buf, end, s, spec)) 734 return buf; 735 736 return string_nocheck(buf, end, s, spec); 737} 738 739static char *pointer_string(char *buf, char *end, 740 const void *ptr, 741 struct printf_spec spec) 742{ 743 spec.base = 16; 744 spec.flags |= SMALL; 745 if (spec.field_width == -1) { 746 spec.field_width = 2 * sizeof(ptr); 747 spec.flags |= ZEROPAD; 748 } 749 750 return number(buf, end, (unsigned long int)ptr, spec); 751} 752 753/* Make pointers available for printing early in the boot sequence. */ 754static int debug_boot_weak_hash __ro_after_init; 755 756static int __init debug_boot_weak_hash_enable(char *str) 757{ 758 debug_boot_weak_hash = 1; 759 pr_info("debug_boot_weak_hash enabled\n"); 760 return 0; 761} 762early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 763 764static bool filled_random_ptr_key __read_mostly; 765static siphash_key_t ptr_key __read_mostly; 766 767static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) 768{ 769 get_random_bytes(&ptr_key, sizeof(ptr_key)); 770 771 /* Pairs with smp_rmb() before reading ptr_key. */ 772 smp_wmb(); 773 WRITE_ONCE(filled_random_ptr_key, true); 774 return NOTIFY_DONE; 775} 776 777static int __init vsprintf_init_hashval(void) 778{ 779 static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; 780 execute_with_initialized_rng(&fill_ptr_key_nb); 781 return 0; 782} 783subsys_initcall(vsprintf_init_hashval) 784 785/* Maps a pointer to a 32 bit unique identifier. */ 786static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 787{ 788 unsigned long hashval; 789 790 if (!READ_ONCE(filled_random_ptr_key)) 791 return -EBUSY; 792 793 /* Pairs with smp_wmb() after writing ptr_key. */ 794 smp_rmb(); 795 796#ifdef CONFIG_64BIT 797 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 798 /* 799 * Mask off the first 32 bits, this makes explicit that we have 800 * modified the address (and 32 bits is plenty for a unique ID). 801 */ 802 hashval = hashval & 0xffffffff; 803#else 804 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 805#endif 806 *hashval_out = hashval; 807 return 0; 808} 809 810int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 811{ 812 return __ptr_to_hashval(ptr, hashval_out); 813} 814 815static char *ptr_to_id(char *buf, char *end, const void *ptr, 816 struct printf_spec spec) 817{ 818 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 819 unsigned long hashval; 820 int ret; 821 822 /* 823 * Print the real pointer value for NULL and error pointers, 824 * as they are not actual addresses. 825 */ 826 if (IS_ERR_OR_NULL(ptr)) 827 return pointer_string(buf, end, ptr, spec); 828 829 /* When debugging early boot use non-cryptographically secure hash. */ 830 if (unlikely(debug_boot_weak_hash)) { 831 hashval = hash_long((unsigned long)ptr, 32); 832 return pointer_string(buf, end, (const void *)hashval, spec); 833 } 834 835 ret = __ptr_to_hashval(ptr, &hashval); 836 if (ret) { 837 spec.field_width = 2 * sizeof(ptr); 838 /* string length must be less than default_width */ 839 return error_string(buf, end, str, spec); 840 } 841 842 return pointer_string(buf, end, (const void *)hashval, spec); 843} 844 845static char *default_pointer(char *buf, char *end, const void *ptr, 846 struct printf_spec spec) 847{ 848 /* 849 * default is to _not_ leak addresses, so hash before printing, 850 * unless no_hash_pointers is specified on the command line. 851 */ 852 if (unlikely(no_hash_pointers)) 853 return pointer_string(buf, end, ptr, spec); 854 855 return ptr_to_id(buf, end, ptr, spec); 856} 857 858int kptr_restrict __read_mostly; 859 860static noinline_for_stack 861char *restricted_pointer(char *buf, char *end, const void *ptr, 862 struct printf_spec spec) 863{ 864 switch (kptr_restrict) { 865 case 0: 866 /* Handle as %p, hash and do _not_ leak addresses. */ 867 return default_pointer(buf, end, ptr, spec); 868 case 1: { 869 const struct cred *cred; 870 871 /* 872 * kptr_restrict==1 cannot be used in IRQ context 873 * because its test for CAP_SYSLOG would be meaningless. 874 */ 875 if (in_hardirq() || in_serving_softirq() || in_nmi()) { 876 if (spec.field_width == -1) 877 spec.field_width = 2 * sizeof(ptr); 878 return error_string(buf, end, "pK-error", spec); 879 } 880 881 /* 882 * Only print the real pointer value if the current 883 * process has CAP_SYSLOG and is running with the 884 * same credentials it started with. This is because 885 * access to files is checked at open() time, but %pK 886 * checks permission at read() time. We don't want to 887 * leak pointer values if a binary opens a file using 888 * %pK and then elevates privileges before reading it. 889 */ 890 cred = current_cred(); 891 if (!has_capability_noaudit(current, CAP_SYSLOG) || 892 !uid_eq(cred->euid, cred->uid) || 893 !gid_eq(cred->egid, cred->gid)) 894 ptr = NULL; 895 break; 896 } 897 case 2: 898 default: 899 /* Always print 0's for %pK */ 900 ptr = NULL; 901 break; 902 } 903 904 return pointer_string(buf, end, ptr, spec); 905} 906 907static noinline_for_stack 908char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 909 const char *fmt) 910{ 911 const char *array[4], *s; 912 const struct dentry *p; 913 int depth; 914 int i, n; 915 916 switch (fmt[1]) { 917 case '2': case '3': case '4': 918 depth = fmt[1] - '0'; 919 break; 920 default: 921 depth = 1; 922 } 923 924 rcu_read_lock(); 925 for (i = 0; i < depth; i++, d = p) { 926 if (check_pointer(&buf, end, d, spec)) { 927 rcu_read_unlock(); 928 return buf; 929 } 930 931 p = READ_ONCE(d->d_parent); 932 array[i] = READ_ONCE(d->d_name.name); 933 if (p == d) { 934 if (i) 935 array[i] = ""; 936 i++; 937 break; 938 } 939 } 940 s = array[--i]; 941 for (n = 0; n != spec.precision; n++, buf++) { 942 char c = *s++; 943 if (!c) { 944 if (!i) 945 break; 946 c = '/'; 947 s = array[--i]; 948 } 949 if (buf < end) 950 *buf = c; 951 } 952 rcu_read_unlock(); 953 return widen_string(buf, n, end, spec); 954} 955 956static noinline_for_stack 957char *file_dentry_name(char *buf, char *end, const struct file *f, 958 struct printf_spec spec, const char *fmt) 959{ 960 if (check_pointer(&buf, end, f, spec)) 961 return buf; 962 963 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 964} 965#ifdef CONFIG_BLOCK 966static noinline_for_stack 967char *bdev_name(char *buf, char *end, struct block_device *bdev, 968 struct printf_spec spec, const char *fmt) 969{ 970 struct gendisk *hd; 971 972 if (check_pointer(&buf, end, bdev, spec)) 973 return buf; 974 975 hd = bdev->bd_disk; 976 buf = string(buf, end, hd->disk_name, spec); 977 if (bdev_is_partition(bdev)) { 978 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 979 if (buf < end) 980 *buf = 'p'; 981 buf++; 982 } 983 buf = number(buf, end, bdev_partno(bdev), spec); 984 } 985 return buf; 986} 987#endif 988 989static noinline_for_stack 990char *symbol_string(char *buf, char *end, void *ptr, 991 struct printf_spec spec, const char *fmt) 992{ 993 unsigned long value; 994#ifdef CONFIG_KALLSYMS 995 char sym[KSYM_SYMBOL_LEN]; 996#endif 997 998 if (fmt[1] == 'R') 999 ptr = __builtin_extract_return_addr(ptr); 1000 value = (unsigned long)ptr; 1001 1002#ifdef CONFIG_KALLSYMS 1003 if (*fmt == 'B' && fmt[1] == 'b') 1004 sprint_backtrace_build_id(sym, value); 1005 else if (*fmt == 'B') 1006 sprint_backtrace(sym, value); 1007 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 1008 sprint_symbol_build_id(sym, value); 1009 else if (*fmt != 's') 1010 sprint_symbol(sym, value); 1011 else 1012 sprint_symbol_no_offset(sym, value); 1013 1014 return string_nocheck(buf, end, sym, spec); 1015#else 1016 return special_hex_number(buf, end, value, sizeof(void *)); 1017#endif 1018} 1019 1020static const struct printf_spec default_str_spec = { 1021 .field_width = -1, 1022 .precision = -1, 1023}; 1024 1025static const struct printf_spec default_flag_spec = { 1026 .base = 16, 1027 .precision = -1, 1028 .flags = SPECIAL | SMALL, 1029}; 1030 1031static const struct printf_spec default_dec_spec = { 1032 .base = 10, 1033 .precision = -1, 1034}; 1035 1036static const struct printf_spec default_dec02_spec = { 1037 .base = 10, 1038 .field_width = 2, 1039 .precision = -1, 1040 .flags = ZEROPAD, 1041}; 1042 1043static const struct printf_spec default_dec04_spec = { 1044 .base = 10, 1045 .field_width = 4, 1046 .precision = -1, 1047 .flags = ZEROPAD, 1048}; 1049 1050static noinline_for_stack 1051char *hex_range(char *buf, char *end, u64 start_val, u64 end_val, 1052 struct printf_spec spec) 1053{ 1054 buf = number(buf, end, start_val, spec); 1055 if (start_val == end_val) 1056 return buf; 1057 1058 if (buf < end) 1059 *buf = '-'; 1060 ++buf; 1061 return number(buf, end, end_val, spec); 1062} 1063 1064static noinline_for_stack 1065char *resource_string(char *buf, char *end, struct resource *res, 1066 struct printf_spec spec, const char *fmt) 1067{ 1068#ifndef IO_RSRC_PRINTK_SIZE 1069#define IO_RSRC_PRINTK_SIZE 6 1070#endif 1071 1072#ifndef MEM_RSRC_PRINTK_SIZE 1073#define MEM_RSRC_PRINTK_SIZE 10 1074#endif 1075 static const struct printf_spec io_spec = { 1076 .base = 16, 1077 .field_width = IO_RSRC_PRINTK_SIZE, 1078 .precision = -1, 1079 .flags = SPECIAL | SMALL | ZEROPAD, 1080 }; 1081 static const struct printf_spec mem_spec = { 1082 .base = 16, 1083 .field_width = MEM_RSRC_PRINTK_SIZE, 1084 .precision = -1, 1085 .flags = SPECIAL | SMALL | ZEROPAD, 1086 }; 1087 static const struct printf_spec bus_spec = { 1088 .base = 16, 1089 .field_width = 2, 1090 .precision = -1, 1091 .flags = SMALL | ZEROPAD, 1092 }; 1093 static const struct printf_spec str_spec = { 1094 .field_width = -1, 1095 .precision = 10, 1096 .flags = LEFT, 1097 }; 1098 1099 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1100 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1101#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1102#define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1103#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1104#define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1105 char sym[MAX(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1106 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1107 1108 char *p = sym, *pend = sym + sizeof(sym); 1109 int decode = (fmt[0] == 'R') ? 1 : 0; 1110 const struct printf_spec *specp; 1111 1112 if (check_pointer(&buf, end, res, spec)) 1113 return buf; 1114 1115 *p++ = '['; 1116 if (res->flags & IORESOURCE_IO) { 1117 p = string_nocheck(p, pend, "io ", str_spec); 1118 specp = &io_spec; 1119 } else if (res->flags & IORESOURCE_MEM) { 1120 p = string_nocheck(p, pend, "mem ", str_spec); 1121 specp = &mem_spec; 1122 } else if (res->flags & IORESOURCE_IRQ) { 1123 p = string_nocheck(p, pend, "irq ", str_spec); 1124 specp = &default_dec_spec; 1125 } else if (res->flags & IORESOURCE_DMA) { 1126 p = string_nocheck(p, pend, "dma ", str_spec); 1127 specp = &default_dec_spec; 1128 } else if (res->flags & IORESOURCE_BUS) { 1129 p = string_nocheck(p, pend, "bus ", str_spec); 1130 specp = &bus_spec; 1131 } else { 1132 p = string_nocheck(p, pend, "??? ", str_spec); 1133 specp = &mem_spec; 1134 decode = 0; 1135 } 1136 if (decode && res->flags & IORESOURCE_UNSET) { 1137 p = string_nocheck(p, pend, "size ", str_spec); 1138 p = number(p, pend, resource_size(res), *specp); 1139 } else { 1140 p = hex_range(p, pend, res->start, res->end, *specp); 1141 } 1142 if (decode) { 1143 if (res->flags & IORESOURCE_MEM_64) 1144 p = string_nocheck(p, pend, " 64bit", str_spec); 1145 if (res->flags & IORESOURCE_PREFETCH) 1146 p = string_nocheck(p, pend, " pref", str_spec); 1147 if (res->flags & IORESOURCE_WINDOW) 1148 p = string_nocheck(p, pend, " window", str_spec); 1149 if (res->flags & IORESOURCE_DISABLED) 1150 p = string_nocheck(p, pend, " disabled", str_spec); 1151 } else { 1152 p = string_nocheck(p, pend, " flags ", str_spec); 1153 p = number(p, pend, res->flags, default_flag_spec); 1154 } 1155 *p++ = ']'; 1156 *p = '\0'; 1157 1158 return string_nocheck(buf, end, sym, spec); 1159} 1160 1161static noinline_for_stack 1162char *range_string(char *buf, char *end, const struct range *range, 1163 struct printf_spec spec, const char *fmt) 1164{ 1165 char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")]; 1166 char *p = sym, *pend = sym + sizeof(sym); 1167 1168 if (check_pointer(&buf, end, range, spec)) 1169 return buf; 1170 1171 p = string_nocheck(p, pend, "[range ", default_str_spec); 1172 p = hex_range(p, pend, range->start, range->end, special_hex_spec(sizeof(range->start))); 1173 *p++ = ']'; 1174 *p = '\0'; 1175 1176 return string_nocheck(buf, end, sym, spec); 1177} 1178 1179static noinline_for_stack 1180char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1181 const char *fmt) 1182{ 1183 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1184 negative value, fallback to the default */ 1185 char separator; 1186 1187 if (spec.field_width == 0) 1188 /* nothing to print */ 1189 return buf; 1190 1191 if (check_pointer(&buf, end, addr, spec)) 1192 return buf; 1193 1194 switch (fmt[1]) { 1195 case 'C': 1196 separator = ':'; 1197 break; 1198 case 'D': 1199 separator = '-'; 1200 break; 1201 case 'N': 1202 separator = 0; 1203 break; 1204 default: 1205 separator = ' '; 1206 break; 1207 } 1208 1209 if (spec.field_width > 0) 1210 len = min_t(int, spec.field_width, 64); 1211 1212 for (i = 0; i < len; ++i) { 1213 if (buf < end) 1214 *buf = hex_asc_hi(addr[i]); 1215 ++buf; 1216 if (buf < end) 1217 *buf = hex_asc_lo(addr[i]); 1218 ++buf; 1219 1220 if (separator && i != len - 1) { 1221 if (buf < end) 1222 *buf = separator; 1223 ++buf; 1224 } 1225 } 1226 1227 return buf; 1228} 1229 1230static noinline_for_stack 1231char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, 1232 struct printf_spec spec, const char *fmt) 1233{ 1234 const int CHUNKSZ = 32; 1235 int nr_bits = max_t(int, spec.field_width, 0); 1236 int i, chunksz; 1237 bool first = true; 1238 1239 if (check_pointer(&buf, end, bitmap, spec)) 1240 return buf; 1241 1242 /* reused to print numbers */ 1243 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1244 1245 chunksz = nr_bits & (CHUNKSZ - 1); 1246 if (chunksz == 0) 1247 chunksz = CHUNKSZ; 1248 1249 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1250 for (; i >= 0; i -= CHUNKSZ) { 1251 u32 chunkmask, val; 1252 int word, bit; 1253 1254 chunkmask = ((1ULL << chunksz) - 1); 1255 word = i / BITS_PER_LONG; 1256 bit = i % BITS_PER_LONG; 1257 val = (bitmap[word] >> bit) & chunkmask; 1258 1259 if (!first) { 1260 if (buf < end) 1261 *buf = ','; 1262 buf++; 1263 } 1264 first = false; 1265 1266 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1267 buf = number(buf, end, val, spec); 1268 1269 chunksz = CHUNKSZ; 1270 } 1271 return buf; 1272} 1273 1274static noinline_for_stack 1275char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, 1276 struct printf_spec spec, const char *fmt) 1277{ 1278 int nr_bits = max_t(int, spec.field_width, 0); 1279 bool first = true; 1280 int rbot, rtop; 1281 1282 if (check_pointer(&buf, end, bitmap, spec)) 1283 return buf; 1284 1285 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1286 if (!first) { 1287 if (buf < end) 1288 *buf = ','; 1289 buf++; 1290 } 1291 first = false; 1292 1293 buf = number(buf, end, rbot, default_dec_spec); 1294 if (rtop == rbot + 1) 1295 continue; 1296 1297 if (buf < end) 1298 *buf = '-'; 1299 buf = number(++buf, end, rtop - 1, default_dec_spec); 1300 } 1301 return buf; 1302} 1303 1304static noinline_for_stack 1305char *mac_address_string(char *buf, char *end, u8 *addr, 1306 struct printf_spec spec, const char *fmt) 1307{ 1308 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1309 char *p = mac_addr; 1310 int i; 1311 char separator; 1312 bool reversed = false; 1313 1314 if (check_pointer(&buf, end, addr, spec)) 1315 return buf; 1316 1317 switch (fmt[1]) { 1318 case 'F': 1319 separator = '-'; 1320 break; 1321 1322 case 'R': 1323 reversed = true; 1324 fallthrough; 1325 1326 default: 1327 separator = ':'; 1328 break; 1329 } 1330 1331 for (i = 0; i < 6; i++) { 1332 if (reversed) 1333 p = hex_byte_pack(p, addr[5 - i]); 1334 else 1335 p = hex_byte_pack(p, addr[i]); 1336 1337 if (fmt[0] == 'M' && i != 5) 1338 *p++ = separator; 1339 } 1340 *p = '\0'; 1341 1342 return string_nocheck(buf, end, mac_addr, spec); 1343} 1344 1345static noinline_for_stack 1346char *ip4_string(char *p, const u8 *addr, const char *fmt) 1347{ 1348 int i; 1349 bool leading_zeros = (fmt[0] == 'i'); 1350 int index; 1351 int step; 1352 1353 switch (fmt[2]) { 1354 case 'h': 1355#ifdef __BIG_ENDIAN 1356 index = 0; 1357 step = 1; 1358#else 1359 index = 3; 1360 step = -1; 1361#endif 1362 break; 1363 case 'l': 1364 index = 3; 1365 step = -1; 1366 break; 1367 case 'n': 1368 case 'b': 1369 default: 1370 index = 0; 1371 step = 1; 1372 break; 1373 } 1374 for (i = 0; i < 4; i++) { 1375 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1376 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1377 if (leading_zeros) { 1378 if (digits < 3) 1379 *p++ = '0'; 1380 if (digits < 2) 1381 *p++ = '0'; 1382 } 1383 /* reverse the digits in the quad */ 1384 while (digits--) 1385 *p++ = temp[digits]; 1386 if (i < 3) 1387 *p++ = '.'; 1388 index += step; 1389 } 1390 *p = '\0'; 1391 1392 return p; 1393} 1394 1395static noinline_for_stack 1396char *ip6_compressed_string(char *p, const char *addr) 1397{ 1398 int i, j, range; 1399 unsigned char zerolength[8]; 1400 int longest = 1; 1401 int colonpos = -1; 1402 u16 word; 1403 u8 hi, lo; 1404 bool needcolon = false; 1405 bool useIPv4; 1406 struct in6_addr in6; 1407 1408 memcpy(&in6, addr, sizeof(struct in6_addr)); 1409 1410 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1411 1412 memset(zerolength, 0, sizeof(zerolength)); 1413 1414 if (useIPv4) 1415 range = 6; 1416 else 1417 range = 8; 1418 1419 /* find position of longest 0 run */ 1420 for (i = 0; i < range; i++) { 1421 for (j = i; j < range; j++) { 1422 if (in6.s6_addr16[j] != 0) 1423 break; 1424 zerolength[i]++; 1425 } 1426 } 1427 for (i = 0; i < range; i++) { 1428 if (zerolength[i] > longest) { 1429 longest = zerolength[i]; 1430 colonpos = i; 1431 } 1432 } 1433 if (longest == 1) /* don't compress a single 0 */ 1434 colonpos = -1; 1435 1436 /* emit address */ 1437 for (i = 0; i < range; i++) { 1438 if (i == colonpos) { 1439 if (needcolon || i == 0) 1440 *p++ = ':'; 1441 *p++ = ':'; 1442 needcolon = false; 1443 i += longest - 1; 1444 continue; 1445 } 1446 if (needcolon) { 1447 *p++ = ':'; 1448 needcolon = false; 1449 } 1450 /* hex u16 without leading 0s */ 1451 word = ntohs(in6.s6_addr16[i]); 1452 hi = word >> 8; 1453 lo = word & 0xff; 1454 if (hi) { 1455 if (hi > 0x0f) 1456 p = hex_byte_pack(p, hi); 1457 else 1458 *p++ = hex_asc_lo(hi); 1459 p = hex_byte_pack(p, lo); 1460 } 1461 else if (lo > 0x0f) 1462 p = hex_byte_pack(p, lo); 1463 else 1464 *p++ = hex_asc_lo(lo); 1465 needcolon = true; 1466 } 1467 1468 if (useIPv4) { 1469 if (needcolon) 1470 *p++ = ':'; 1471 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1472 } 1473 *p = '\0'; 1474 1475 return p; 1476} 1477 1478static noinline_for_stack 1479char *ip6_string(char *p, const char *addr, const char *fmt) 1480{ 1481 int i; 1482 1483 for (i = 0; i < 8; i++) { 1484 p = hex_byte_pack(p, *addr++); 1485 p = hex_byte_pack(p, *addr++); 1486 if (fmt[0] == 'I' && i != 7) 1487 *p++ = ':'; 1488 } 1489 *p = '\0'; 1490 1491 return p; 1492} 1493 1494static noinline_for_stack 1495char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1496 struct printf_spec spec, const char *fmt) 1497{ 1498 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1499 1500 if (fmt[0] == 'I' && fmt[2] == 'c') 1501 ip6_compressed_string(ip6_addr, addr); 1502 else 1503 ip6_string(ip6_addr, addr, fmt); 1504 1505 return string_nocheck(buf, end, ip6_addr, spec); 1506} 1507 1508static noinline_for_stack 1509char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1510 struct printf_spec spec, const char *fmt) 1511{ 1512 char ip4_addr[sizeof("255.255.255.255")]; 1513 1514 ip4_string(ip4_addr, addr, fmt); 1515 1516 return string_nocheck(buf, end, ip4_addr, spec); 1517} 1518 1519static noinline_for_stack 1520char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1521 struct printf_spec spec, const char *fmt) 1522{ 1523 bool have_p = false, have_s = false, have_f = false, have_c = false; 1524 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1525 sizeof(":12345") + sizeof("/123456789") + 1526 sizeof("%1234567890")]; 1527 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1528 const u8 *addr = (const u8 *) &sa->sin6_addr; 1529 char fmt6[2] = { fmt[0], '6' }; 1530 u8 off = 0; 1531 1532 fmt++; 1533 while (isalpha(*++fmt)) { 1534 switch (*fmt) { 1535 case 'p': 1536 have_p = true; 1537 break; 1538 case 'f': 1539 have_f = true; 1540 break; 1541 case 's': 1542 have_s = true; 1543 break; 1544 case 'c': 1545 have_c = true; 1546 break; 1547 } 1548 } 1549 1550 if (have_p || have_s || have_f) { 1551 *p = '['; 1552 off = 1; 1553 } 1554 1555 if (fmt6[0] == 'I' && have_c) 1556 p = ip6_compressed_string(ip6_addr + off, addr); 1557 else 1558 p = ip6_string(ip6_addr + off, addr, fmt6); 1559 1560 if (have_p || have_s || have_f) 1561 *p++ = ']'; 1562 1563 if (have_p) { 1564 *p++ = ':'; 1565 p = number(p, pend, ntohs(sa->sin6_port), spec); 1566 } 1567 if (have_f) { 1568 *p++ = '/'; 1569 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1570 IPV6_FLOWINFO_MASK), spec); 1571 } 1572 if (have_s) { 1573 *p++ = '%'; 1574 p = number(p, pend, sa->sin6_scope_id, spec); 1575 } 1576 *p = '\0'; 1577 1578 return string_nocheck(buf, end, ip6_addr, spec); 1579} 1580 1581static noinline_for_stack 1582char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1583 struct printf_spec spec, const char *fmt) 1584{ 1585 bool have_p = false; 1586 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1587 char *pend = ip4_addr + sizeof(ip4_addr); 1588 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1589 char fmt4[3] = { fmt[0], '4', 0 }; 1590 1591 fmt++; 1592 while (isalpha(*++fmt)) { 1593 switch (*fmt) { 1594 case 'p': 1595 have_p = true; 1596 break; 1597 case 'h': 1598 case 'l': 1599 case 'n': 1600 case 'b': 1601 fmt4[2] = *fmt; 1602 break; 1603 } 1604 } 1605 1606 p = ip4_string(ip4_addr, addr, fmt4); 1607 if (have_p) { 1608 *p++ = ':'; 1609 p = number(p, pend, ntohs(sa->sin_port), spec); 1610 } 1611 *p = '\0'; 1612 1613 return string_nocheck(buf, end, ip4_addr, spec); 1614} 1615 1616static noinline_for_stack 1617char *ip_addr_string(char *buf, char *end, const void *ptr, 1618 struct printf_spec spec, const char *fmt) 1619{ 1620 char *err_fmt_msg; 1621 1622 if (check_pointer(&buf, end, ptr, spec)) 1623 return buf; 1624 1625 switch (fmt[1]) { 1626 case '6': 1627 return ip6_addr_string(buf, end, ptr, spec, fmt); 1628 case '4': 1629 return ip4_addr_string(buf, end, ptr, spec, fmt); 1630 case 'S': { 1631 const union { 1632 struct sockaddr raw; 1633 struct sockaddr_in v4; 1634 struct sockaddr_in6 v6; 1635 } *sa = ptr; 1636 1637 switch (sa->raw.sa_family) { 1638 case AF_INET: 1639 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1640 case AF_INET6: 1641 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1642 default: 1643 return error_string(buf, end, "(einval)", spec); 1644 }} 1645 } 1646 1647 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1648 return error_string(buf, end, err_fmt_msg, spec); 1649} 1650 1651static noinline_for_stack 1652char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1653 const char *fmt) 1654{ 1655 bool found = true; 1656 int count = 1; 1657 unsigned int flags = 0; 1658 int len; 1659 1660 if (spec.field_width == 0) 1661 return buf; /* nothing to print */ 1662 1663 if (check_pointer(&buf, end, addr, spec)) 1664 return buf; 1665 1666 do { 1667 switch (fmt[count++]) { 1668 case 'a': 1669 flags |= ESCAPE_ANY; 1670 break; 1671 case 'c': 1672 flags |= ESCAPE_SPECIAL; 1673 break; 1674 case 'h': 1675 flags |= ESCAPE_HEX; 1676 break; 1677 case 'n': 1678 flags |= ESCAPE_NULL; 1679 break; 1680 case 'o': 1681 flags |= ESCAPE_OCTAL; 1682 break; 1683 case 'p': 1684 flags |= ESCAPE_NP; 1685 break; 1686 case 's': 1687 flags |= ESCAPE_SPACE; 1688 break; 1689 default: 1690 found = false; 1691 break; 1692 } 1693 } while (found); 1694 1695 if (!flags) 1696 flags = ESCAPE_ANY_NP; 1697 1698 len = spec.field_width < 0 ? 1 : spec.field_width; 1699 1700 /* 1701 * string_escape_mem() writes as many characters as it can to 1702 * the given buffer, and returns the total size of the output 1703 * had the buffer been big enough. 1704 */ 1705 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1706 1707 return buf; 1708} 1709 1710__diag_push(); 1711__diag_ignore(GCC, all, "-Wsuggest-attribute=format", 1712 "Not a valid __printf() conversion candidate."); 1713static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1714 struct printf_spec spec) 1715{ 1716 va_list va; 1717 1718 if (check_pointer(&buf, end, va_fmt, spec)) 1719 return buf; 1720 1721 va_copy(va, *va_fmt->va); 1722 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1723 va_end(va); 1724 1725 return buf; 1726} 1727__diag_pop(); 1728 1729static noinline_for_stack 1730char *uuid_string(char *buf, char *end, const u8 *addr, 1731 struct printf_spec spec, const char *fmt) 1732{ 1733 char uuid[UUID_STRING_LEN + 1]; 1734 char *p = uuid; 1735 int i; 1736 const u8 *index = uuid_index; 1737 bool uc = false; 1738 1739 if (check_pointer(&buf, end, addr, spec)) 1740 return buf; 1741 1742 switch (*(++fmt)) { 1743 case 'L': 1744 uc = true; 1745 fallthrough; 1746 case 'l': 1747 index = guid_index; 1748 break; 1749 case 'B': 1750 uc = true; 1751 break; 1752 } 1753 1754 for (i = 0; i < 16; i++) { 1755 if (uc) 1756 p = hex_byte_pack_upper(p, addr[index[i]]); 1757 else 1758 p = hex_byte_pack(p, addr[index[i]]); 1759 switch (i) { 1760 case 3: 1761 case 5: 1762 case 7: 1763 case 9: 1764 *p++ = '-'; 1765 break; 1766 } 1767 } 1768 1769 *p = 0; 1770 1771 return string_nocheck(buf, end, uuid, spec); 1772} 1773 1774static noinline_for_stack 1775char *netdev_bits(char *buf, char *end, const void *addr, 1776 struct printf_spec spec, const char *fmt) 1777{ 1778 unsigned long long num; 1779 int size; 1780 1781 if (check_pointer(&buf, end, addr, spec)) 1782 return buf; 1783 1784 switch (fmt[1]) { 1785 case 'F': 1786 num = *(const netdev_features_t *)addr; 1787 size = sizeof(netdev_features_t); 1788 break; 1789 default: 1790 return error_string(buf, end, "(%pN?)", spec); 1791 } 1792 1793 return special_hex_number(buf, end, num, size); 1794} 1795 1796static noinline_for_stack 1797char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1798 struct printf_spec spec, const char *fmt) 1799{ 1800 char output[sizeof("0123 little-endian (0x01234567)")]; 1801 char *p = output; 1802 unsigned int i; 1803 bool pixel_fmt = false; 1804 u32 orig, val; 1805 1806 if (fmt[1] != 'c') 1807 return error_string(buf, end, "(%p4?)", spec); 1808 1809 if (check_pointer(&buf, end, fourcc, spec)) 1810 return buf; 1811 1812 orig = get_unaligned(fourcc); 1813 switch (fmt[2]) { 1814 case 'h': 1815 if (fmt[3] == 'R') 1816 orig = swab32(orig); 1817 break; 1818 case 'l': 1819 orig = (__force u32)cpu_to_le32(orig); 1820 break; 1821 case 'b': 1822 orig = (__force u32)cpu_to_be32(orig); 1823 break; 1824 case 'c': 1825 /* Pixel formats are printed LSB-first */ 1826 pixel_fmt = true; 1827 break; 1828 default: 1829 return error_string(buf, end, "(%p4?)", spec); 1830 } 1831 1832 val = pixel_fmt ? swab32(orig & ~BIT(31)) : orig; 1833 1834 for (i = 0; i < sizeof(u32); i++) { 1835 unsigned char c = val >> ((3 - i) * 8); 1836 1837 /* Print non-control ASCII characters as-is, dot otherwise */ 1838 *p++ = isascii(c) && isprint(c) ? c : '.'; 1839 } 1840 1841 if (pixel_fmt) { 1842 *p++ = ' '; 1843 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1844 p += strlen(p); 1845 } 1846 1847 *p++ = ' '; 1848 *p++ = '('; 1849 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1850 *p++ = ')'; 1851 *p = '\0'; 1852 1853 return string(buf, end, output, spec); 1854} 1855 1856static noinline_for_stack 1857char *address_val(char *buf, char *end, const void *addr, 1858 struct printf_spec spec, const char *fmt) 1859{ 1860 unsigned long long num; 1861 int size; 1862 1863 if (check_pointer(&buf, end, addr, spec)) 1864 return buf; 1865 1866 switch (fmt[1]) { 1867 case 'd': 1868 num = *(const dma_addr_t *)addr; 1869 size = sizeof(dma_addr_t); 1870 break; 1871 case 'p': 1872 default: 1873 num = *(const phys_addr_t *)addr; 1874 size = sizeof(phys_addr_t); 1875 break; 1876 } 1877 1878 return special_hex_number(buf, end, num, size); 1879} 1880 1881static noinline_for_stack 1882char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1883{ 1884 int year = tm->tm_year + (r ? 0 : 1900); 1885 int mon = tm->tm_mon + (r ? 0 : 1); 1886 1887 buf = number(buf, end, year, default_dec04_spec); 1888 if (buf < end) 1889 *buf = '-'; 1890 buf++; 1891 1892 buf = number(buf, end, mon, default_dec02_spec); 1893 if (buf < end) 1894 *buf = '-'; 1895 buf++; 1896 1897 return number(buf, end, tm->tm_mday, default_dec02_spec); 1898} 1899 1900static noinline_for_stack 1901char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1902{ 1903 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1904 if (buf < end) 1905 *buf = ':'; 1906 buf++; 1907 1908 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1909 if (buf < end) 1910 *buf = ':'; 1911 buf++; 1912 1913 return number(buf, end, tm->tm_sec, default_dec02_spec); 1914} 1915 1916static noinline_for_stack 1917char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1918 struct printf_spec spec, const char *fmt) 1919{ 1920 bool have_t = true, have_d = true; 1921 bool raw = false, iso8601_separator = true; 1922 bool found = true; 1923 int count = 2; 1924 1925 switch (fmt[count]) { 1926 case 'd': 1927 have_t = false; 1928 count++; 1929 break; 1930 case 't': 1931 have_d = false; 1932 count++; 1933 break; 1934 } 1935 1936 do { 1937 switch (fmt[count++]) { 1938 case 'r': 1939 raw = true; 1940 break; 1941 case 's': 1942 iso8601_separator = false; 1943 break; 1944 default: 1945 found = false; 1946 break; 1947 } 1948 } while (found); 1949 1950 if (have_d) 1951 buf = date_str(buf, end, tm, raw); 1952 if (have_d && have_t) { 1953 if (buf < end) 1954 *buf = iso8601_separator ? 'T' : ' '; 1955 buf++; 1956 } 1957 if (have_t) 1958 buf = time_str(buf, end, tm, raw); 1959 1960 return buf; 1961} 1962 1963static noinline_for_stack 1964char *time64_str(char *buf, char *end, const time64_t time, 1965 struct printf_spec spec, const char *fmt) 1966{ 1967 struct rtc_time rtc_time; 1968 struct tm tm; 1969 1970 time64_to_tm(time, 0, &tm); 1971 1972 rtc_time.tm_sec = tm.tm_sec; 1973 rtc_time.tm_min = tm.tm_min; 1974 rtc_time.tm_hour = tm.tm_hour; 1975 rtc_time.tm_mday = tm.tm_mday; 1976 rtc_time.tm_mon = tm.tm_mon; 1977 rtc_time.tm_year = tm.tm_year; 1978 rtc_time.tm_wday = tm.tm_wday; 1979 rtc_time.tm_yday = tm.tm_yday; 1980 1981 rtc_time.tm_isdst = 0; 1982 1983 return rtc_str(buf, end, &rtc_time, spec, fmt); 1984} 1985 1986static noinline_for_stack 1987char *timespec64_str(char *buf, char *end, const struct timespec64 *ts, 1988 struct printf_spec spec, const char *fmt) 1989{ 1990 static const struct printf_spec default_dec09_spec = { 1991 .base = 10, 1992 .field_width = 9, 1993 .precision = -1, 1994 .flags = ZEROPAD, 1995 }; 1996 1997 if (fmt[2] == 'p') 1998 buf = number(buf, end, ts->tv_sec, default_dec_spec); 1999 else 2000 buf = time64_str(buf, end, ts->tv_sec, spec, fmt); 2001 if (buf < end) 2002 *buf = '.'; 2003 buf++; 2004 2005 return number(buf, end, ts->tv_nsec, default_dec09_spec); 2006} 2007 2008static noinline_for_stack 2009char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 2010 const char *fmt) 2011{ 2012 if (check_pointer(&buf, end, ptr, spec)) 2013 return buf; 2014 2015 switch (fmt[1]) { 2016 case 'R': 2017 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 2018 case 'S': 2019 return timespec64_str(buf, end, (const struct timespec64 *)ptr, spec, fmt); 2020 case 'T': 2021 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 2022 default: 2023 return error_string(buf, end, "(%pt?)", spec); 2024 } 2025} 2026 2027static noinline_for_stack 2028char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 2029 const char *fmt) 2030{ 2031 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 2032 return error_string(buf, end, "(%pC?)", spec); 2033 2034 if (check_pointer(&buf, end, clk, spec)) 2035 return buf; 2036 2037#ifdef CONFIG_COMMON_CLK 2038 return string(buf, end, __clk_get_name(clk), spec); 2039#else 2040 return ptr_to_id(buf, end, clk, spec); 2041#endif 2042} 2043 2044static 2045char *format_flags(char *buf, char *end, unsigned long flags, 2046 const struct trace_print_flags *names) 2047{ 2048 unsigned long mask; 2049 2050 for ( ; flags && names->name; names++) { 2051 mask = names->mask; 2052 if ((flags & mask) != mask) 2053 continue; 2054 2055 buf = string(buf, end, names->name, default_str_spec); 2056 2057 flags &= ~mask; 2058 if (flags) { 2059 if (buf < end) 2060 *buf = '|'; 2061 buf++; 2062 } 2063 } 2064 2065 if (flags) 2066 buf = number(buf, end, flags, default_flag_spec); 2067 2068 return buf; 2069} 2070 2071struct page_flags_fields { 2072 int width; 2073 int shift; 2074 int mask; 2075 const struct printf_spec *spec; 2076 const char *name; 2077}; 2078 2079static const struct page_flags_fields pff[] = { 2080 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 2081 &default_dec_spec, "section"}, 2082 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2083 &default_dec_spec, "node"}, 2084 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2085 &default_dec_spec, "zone"}, 2086 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2087 &default_flag_spec, "lastcpupid"}, 2088 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2089 &default_flag_spec, "kasantag"}, 2090}; 2091 2092static 2093char *format_page_flags(char *buf, char *end, unsigned long flags) 2094{ 2095 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2096 bool append = false; 2097 int i; 2098 2099 buf = number(buf, end, flags, default_flag_spec); 2100 if (buf < end) 2101 *buf = '('; 2102 buf++; 2103 2104 /* Page flags from the main area. */ 2105 if (main_flags) { 2106 buf = format_flags(buf, end, main_flags, pageflag_names); 2107 append = true; 2108 } 2109 2110 /* Page flags from the fields area */ 2111 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2112 /* Skip undefined fields. */ 2113 if (!pff[i].width) 2114 continue; 2115 2116 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2117 if (append) { 2118 if (buf < end) 2119 *buf = '|'; 2120 buf++; 2121 } 2122 2123 buf = string(buf, end, pff[i].name, default_str_spec); 2124 if (buf < end) 2125 *buf = '='; 2126 buf++; 2127 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2128 *pff[i].spec); 2129 2130 append = true; 2131 } 2132 if (buf < end) 2133 *buf = ')'; 2134 buf++; 2135 2136 return buf; 2137} 2138 2139static noinline_for_stack 2140char *flags_string(char *buf, char *end, void *flags_ptr, 2141 struct printf_spec spec, const char *fmt) 2142{ 2143 unsigned long flags; 2144 const struct trace_print_flags *names; 2145 2146 if (check_pointer(&buf, end, flags_ptr, spec)) 2147 return buf; 2148 2149 switch (fmt[1]) { 2150 case 'p': 2151 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2152 case 'v': 2153 flags = *(unsigned long *)flags_ptr; 2154 names = vmaflag_names; 2155 break; 2156 case 'g': 2157 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2158 names = gfpflag_names; 2159 break; 2160 default: 2161 return error_string(buf, end, "(%pG?)", spec); 2162 } 2163 2164 return format_flags(buf, end, flags, names); 2165} 2166 2167static noinline_for_stack 2168char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2169 char *end) 2170{ 2171 int depth; 2172 2173 /* Loop starting from the root node to the current node. */ 2174 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2175 /* 2176 * Only get a reference for other nodes (i.e. parent nodes). 2177 * fwnode refcount may be 0 here. 2178 */ 2179 struct fwnode_handle *__fwnode = depth ? 2180 fwnode_get_nth_parent(fwnode, depth) : fwnode; 2181 2182 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2183 default_str_spec); 2184 buf = string(buf, end, fwnode_get_name(__fwnode), 2185 default_str_spec); 2186 2187 if (depth) 2188 fwnode_handle_put(__fwnode); 2189 } 2190 2191 return buf; 2192} 2193 2194static noinline_for_stack 2195char *device_node_string(char *buf, char *end, struct device_node *dn, 2196 struct printf_spec spec, const char *fmt) 2197{ 2198 char tbuf[sizeof("xxxx") + 1]; 2199 const char *p; 2200 int ret; 2201 char *buf_start = buf; 2202 struct property *prop; 2203 bool has_mult, pass; 2204 2205 struct printf_spec str_spec = spec; 2206 str_spec.field_width = -1; 2207 2208 if (fmt[0] != 'F') 2209 return error_string(buf, end, "(%pO?)", spec); 2210 2211 if (!IS_ENABLED(CONFIG_OF)) 2212 return error_string(buf, end, "(%pOF?)", spec); 2213 2214 if (check_pointer(&buf, end, dn, spec)) 2215 return buf; 2216 2217 /* simple case without anything any more format specifiers */ 2218 fmt++; 2219 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2220 fmt = "f"; 2221 2222 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2223 int precision; 2224 if (pass) { 2225 if (buf < end) 2226 *buf = ':'; 2227 buf++; 2228 } 2229 2230 switch (*fmt) { 2231 case 'f': /* full_name */ 2232 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2233 end); 2234 break; 2235 case 'n': /* name */ 2236 p = fwnode_get_name(of_fwnode_handle(dn)); 2237 precision = str_spec.precision; 2238 str_spec.precision = strchrnul(p, '@') - p; 2239 buf = string(buf, end, p, str_spec); 2240 str_spec.precision = precision; 2241 break; 2242 case 'p': /* phandle */ 2243 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2244 break; 2245 case 'P': /* path-spec */ 2246 p = fwnode_get_name(of_fwnode_handle(dn)); 2247 if (!p[1]) 2248 p = "/"; 2249 buf = string(buf, end, p, str_spec); 2250 break; 2251 case 'F': /* flags */ 2252 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2253 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2254 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2255 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2256 tbuf[4] = 0; 2257 buf = string_nocheck(buf, end, tbuf, str_spec); 2258 break; 2259 case 'c': /* major compatible string */ 2260 ret = of_property_read_string(dn, "compatible", &p); 2261 if (!ret) 2262 buf = string(buf, end, p, str_spec); 2263 break; 2264 case 'C': /* full compatible string */ 2265 has_mult = false; 2266 of_property_for_each_string(dn, "compatible", prop, p) { 2267 if (has_mult) 2268 buf = string_nocheck(buf, end, ",", str_spec); 2269 buf = string_nocheck(buf, end, "\"", str_spec); 2270 buf = string(buf, end, p, str_spec); 2271 buf = string_nocheck(buf, end, "\"", str_spec); 2272 2273 has_mult = true; 2274 } 2275 break; 2276 default: 2277 break; 2278 } 2279 } 2280 2281 return widen_string(buf, buf - buf_start, end, spec); 2282} 2283 2284static noinline_for_stack 2285char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2286 struct printf_spec spec, const char *fmt) 2287{ 2288 struct printf_spec str_spec = spec; 2289 char *buf_start = buf; 2290 2291 str_spec.field_width = -1; 2292 2293 if (*fmt != 'w') 2294 return error_string(buf, end, "(%pf?)", spec); 2295 2296 if (check_pointer(&buf, end, fwnode, spec)) 2297 return buf; 2298 2299 fmt++; 2300 2301 switch (*fmt) { 2302 case 'P': /* name */ 2303 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2304 break; 2305 case 'f': /* full_name */ 2306 default: 2307 buf = fwnode_full_name_string(fwnode, buf, end); 2308 break; 2309 } 2310 2311 return widen_string(buf, buf - buf_start, end, spec); 2312} 2313 2314static noinline_for_stack 2315char *resource_or_range(const char *fmt, char *buf, char *end, void *ptr, 2316 struct printf_spec spec) 2317{ 2318 if (*fmt == 'r' && fmt[1] == 'a') 2319 return range_string(buf, end, ptr, spec, fmt); 2320 return resource_string(buf, end, ptr, spec, fmt); 2321} 2322 2323void __init hash_pointers_finalize(bool slub_debug) 2324{ 2325 switch (hash_pointers_mode) { 2326 case HASH_PTR_ALWAYS: 2327 no_hash_pointers = false; 2328 break; 2329 case HASH_PTR_NEVER: 2330 no_hash_pointers = true; 2331 break; 2332 case HASH_PTR_AUTO: 2333 default: 2334 no_hash_pointers = slub_debug; 2335 break; 2336 } 2337 2338 if (!no_hash_pointers) 2339 return; 2340 2341 pr_warn("**********************************************************\n"); 2342 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2343 pr_warn("** **\n"); 2344 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2345 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2346 pr_warn("** might reduce the security of your system. **\n"); 2347 pr_warn("** **\n"); 2348 pr_warn("** If you see this message and you are not debugging **\n"); 2349 pr_warn("** the kernel, report this immediately to your system **\n"); 2350 pr_warn("** administrator! **\n"); 2351 pr_warn("** **\n"); 2352 pr_warn("** Use hash_pointers=always to force this mode off **\n"); 2353 pr_warn("** **\n"); 2354 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2355 pr_warn("**********************************************************\n"); 2356} 2357 2358static int __init hash_pointers_mode_parse(char *str) 2359{ 2360 if (!str) { 2361 pr_warn("Hash pointers mode empty; falling back to auto.\n"); 2362 hash_pointers_mode = HASH_PTR_AUTO; 2363 } else if (strncmp(str, "auto", 4) == 0) { 2364 pr_info("Hash pointers mode set to auto.\n"); 2365 hash_pointers_mode = HASH_PTR_AUTO; 2366 } else if (strncmp(str, "never", 5) == 0) { 2367 pr_info("Hash pointers mode set to never.\n"); 2368 hash_pointers_mode = HASH_PTR_NEVER; 2369 } else if (strncmp(str, "always", 6) == 0) { 2370 pr_info("Hash pointers mode set to always.\n"); 2371 hash_pointers_mode = HASH_PTR_ALWAYS; 2372 } else { 2373 pr_warn("Unknown hash_pointers mode '%s' specified; assuming auto.\n", str); 2374 hash_pointers_mode = HASH_PTR_AUTO; 2375 } 2376 2377 return 0; 2378} 2379early_param("hash_pointers", hash_pointers_mode_parse); 2380 2381static int __init no_hash_pointers_enable(char *str) 2382{ 2383 return hash_pointers_mode_parse("never"); 2384} 2385early_param("no_hash_pointers", no_hash_pointers_enable); 2386 2387/* 2388 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2389 * by an extra set of alphanumeric characters that are extended format 2390 * specifiers. 2391 * 2392 * Please update scripts/checkpatch.pl when adding/removing conversion 2393 * characters. (Search for "check for vsprintf extension"). 2394 * 2395 * Right now we handle: 2396 * 2397 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2398 * - 's' For symbolic direct pointers (or function descriptors) without offset 2399 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2400 * - 'S[R]b' as above with module build ID (for use in backtraces) 2401 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2402 * %ps and %pS. Be careful when re-using these specifiers. 2403 * - 'B' For backtraced symbolic direct pointers with offset 2404 * - 'Bb' as above with module build ID (for use in backtraces) 2405 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2406 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2407 * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] 2408 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2409 * width which must be explicitly specified either as part of the 2410 * format string '%32b[l]' or through '%*b[l]', [l] selects 2411 * range-list format instead of hex format 2412 * - 'M' For a 6-byte MAC address, it prints the address in the 2413 * usual colon-separated hex notation 2414 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2415 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2416 * with a dash-separated hex notation 2417 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2418 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2419 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2420 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2421 * [S][pfs] 2422 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2423 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2424 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2425 * IPv6 omits the colons (01020304...0f) 2426 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2427 * [S][pfs] 2428 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2429 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2430 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2431 * - 'I[6S]c' for IPv6 addresses printed as specified by 2432 * https://tools.ietf.org/html/rfc5952 2433 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2434 * of the following flags (see string_escape_mem() for the 2435 * details): 2436 * a - ESCAPE_ANY 2437 * c - ESCAPE_SPECIAL 2438 * h - ESCAPE_HEX 2439 * n - ESCAPE_NULL 2440 * o - ESCAPE_OCTAL 2441 * p - ESCAPE_NP 2442 * s - ESCAPE_SPACE 2443 * By default ESCAPE_ANY_NP is used. 2444 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2445 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2446 * Options for %pU are: 2447 * b big endian lower case hex (default) 2448 * B big endian UPPER case hex 2449 * l little endian lower case hex 2450 * L little endian UPPER case hex 2451 * big endian output byte order is: 2452 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2453 * little endian output byte order is: 2454 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2455 * - 'V' For a struct va_format which contains a format string * and va_list *, 2456 * call vsnprintf(->format, *->va_list). 2457 * Implements a "recursive vsnprintf". 2458 * Do not use this feature without some mechanism to verify the 2459 * correctness of the format string and va_list arguments. 2460 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2461 * Use only for procfs, sysfs and similar files, not printk(); please 2462 * read the documentation (path below) first. 2463 * - 'NF' For a netdev_features_t 2464 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2465 * - '4c[h[R]lb]' For generic FourCC code with raw numerical value. Both are 2466 * displayed in the big-endian format. This is the opposite of V4L2 or 2467 * DRM FourCCs. 2468 * The additional specifiers define what endianness is used to load 2469 * the stored bytes. The data might be interpreted using the host, 2470 * reversed host byte order, little-endian, or big-endian. 2471 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2472 * a certain separator (' ' by default): 2473 * C colon 2474 * D dash 2475 * N no separator 2476 * The maximum supported length is 64 bytes of the input. Consider 2477 * to use print_hex_dump() for the larger input. 2478 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2479 * (default assumed to be phys_addr_t, passed by reference) 2480 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2481 * - 'D[234]' Same as 'd' but for a struct file 2482 * - 'g' For block_device name (gendisk + partition number) 2483 * - 't[RST][dt][r][s]' For time and date as represented by: 2484 * R struct rtc_time 2485 * S struct timespec64 2486 * T time64_t 2487 * - 'tSp' For time represented by struct timespec64 printed as <seconds>.<nanoseconds> 2488 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2489 * (legacy clock framework) of the clock 2490 * - 'G' For flags to be printed as a collection of symbolic strings that would 2491 * construct the specific value. Supported flags given by option: 2492 * p page flags (see struct page) given as pointer to unsigned long 2493 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2494 * v vma flags (VM_*) given as pointer to unsigned long 2495 * - 'OF[fnpPcCF]' For a device tree object 2496 * Without any optional arguments prints the full_name 2497 * f device node full_name 2498 * n device node name 2499 * p device node phandle 2500 * P device node path spec (name + @unit) 2501 * F device node flags 2502 * c major compatible string 2503 * C full compatible string 2504 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2505 * Without an option prints the full name of the node 2506 * f full name 2507 * P node name, including a possible unit address 2508 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2509 * Please read the documentation (path below) before using! 2510 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2511 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2512 * or user (u) memory to probe, and: 2513 * s a string, equivalent to "%s" on direct vsnprintf() use 2514 * 2515 * ** When making changes please also update: 2516 * Documentation/core-api/printk-formats.rst 2517 * 2518 * Note: The default behaviour (unadorned %p) is to hash the address, 2519 * rendering it useful as a unique identifier. 2520 * 2521 * There is also a '%pA' format specifier, but it is only intended to be used 2522 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2523 * See rust/kernel/print.rs for details. 2524 */ 2525static noinline_for_stack 2526char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2527 struct printf_spec spec) 2528{ 2529 switch (*fmt) { 2530 case 'S': 2531 case 's': 2532 ptr = dereference_symbol_descriptor(ptr); 2533 fallthrough; 2534 case 'B': 2535 return symbol_string(buf, end, ptr, spec, fmt); 2536 case 'R': 2537 case 'r': 2538 return resource_or_range(fmt, buf, end, ptr, spec); 2539 case 'h': 2540 return hex_string(buf, end, ptr, spec, fmt); 2541 case 'b': 2542 switch (fmt[1]) { 2543 case 'l': 2544 return bitmap_list_string(buf, end, ptr, spec, fmt); 2545 default: 2546 return bitmap_string(buf, end, ptr, spec, fmt); 2547 } 2548 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2549 case 'm': /* Contiguous: 000102030405 */ 2550 /* [mM]F (FDDI) */ 2551 /* [mM]R (Reverse order; Bluetooth) */ 2552 return mac_address_string(buf, end, ptr, spec, fmt); 2553 case 'I': /* Formatted IP supported 2554 * 4: 1.2.3.4 2555 * 6: 0001:0203:...:0708 2556 * 6c: 1::708 or 1::1.2.3.4 2557 */ 2558 case 'i': /* Contiguous: 2559 * 4: 001.002.003.004 2560 * 6: 000102...0f 2561 */ 2562 return ip_addr_string(buf, end, ptr, spec, fmt); 2563 case 'E': 2564 return escaped_string(buf, end, ptr, spec, fmt); 2565 case 'U': 2566 return uuid_string(buf, end, ptr, spec, fmt); 2567 case 'V': 2568 return va_format(buf, end, ptr, spec); 2569 case 'K': 2570 return restricted_pointer(buf, end, ptr, spec); 2571 case 'N': 2572 return netdev_bits(buf, end, ptr, spec, fmt); 2573 case '4': 2574 return fourcc_string(buf, end, ptr, spec, fmt); 2575 case 'a': 2576 return address_val(buf, end, ptr, spec, fmt); 2577 case 'd': 2578 return dentry_name(buf, end, ptr, spec, fmt); 2579 case 't': 2580 return time_and_date(buf, end, ptr, spec, fmt); 2581 case 'C': 2582 return clock(buf, end, ptr, spec, fmt); 2583 case 'D': 2584 return file_dentry_name(buf, end, ptr, spec, fmt); 2585#ifdef CONFIG_BLOCK 2586 case 'g': 2587 return bdev_name(buf, end, ptr, spec, fmt); 2588#endif 2589 2590 case 'G': 2591 return flags_string(buf, end, ptr, spec, fmt); 2592 case 'O': 2593 return device_node_string(buf, end, ptr, spec, fmt + 1); 2594 case 'f': 2595 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2596 case 'A': 2597 if (!IS_ENABLED(CONFIG_RUST)) { 2598 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2599 return error_string(buf, end, "(%pA?)", spec); 2600 } 2601 return rust_fmt_argument(buf, end, ptr); 2602 case 'x': 2603 return pointer_string(buf, end, ptr, spec); 2604 case 'e': 2605 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2606 if (!IS_ERR(ptr)) 2607 return default_pointer(buf, end, ptr, spec); 2608 return err_ptr(buf, end, ptr, spec); 2609 case 'u': 2610 case 'k': 2611 switch (fmt[1]) { 2612 case 's': 2613 return string(buf, end, ptr, spec); 2614 default: 2615 return error_string(buf, end, "(einval)", spec); 2616 } 2617 default: 2618 return default_pointer(buf, end, ptr, spec); 2619 } 2620} 2621 2622struct fmt { 2623 const char *str; 2624 unsigned char state; // enum format_state 2625 unsigned char size; // size of numbers 2626}; 2627 2628#define SPEC_CHAR(x, flag) [(x)-32] = flag 2629static unsigned char spec_flag(unsigned char c) 2630{ 2631 static const unsigned char spec_flag_array[] = { 2632 SPEC_CHAR(' ', SPACE), 2633 SPEC_CHAR('#', SPECIAL), 2634 SPEC_CHAR('+', PLUS), 2635 SPEC_CHAR('-', LEFT), 2636 SPEC_CHAR('0', ZEROPAD), 2637 }; 2638 c -= 32; 2639 return (c < sizeof(spec_flag_array)) ? spec_flag_array[c] : 0; 2640} 2641 2642/* 2643 * Helper function to decode printf style format. 2644 * Each call decode a token from the format and return the 2645 * number of characters read (or likely the delta where it wants 2646 * to go on the next call). 2647 * The decoded token is returned through the parameters 2648 * 2649 * 'h', 'l', or 'L' for integer fields 2650 * 'z' support added 23/7/1999 S.H. 2651 * 'z' changed to 'Z' --davidm 1/25/99 2652 * 'Z' changed to 'z' --adobriyan 2017-01-25 2653 * 't' added for ptrdiff_t 2654 * 2655 * @fmt: the format string 2656 * @type of the token returned 2657 * @flags: various flags such as +, -, # tokens.. 2658 * @field_width: overwritten width 2659 * @base: base of the number (octal, hex, ...) 2660 * @precision: precision of a number 2661 * @qualifier: qualifier of a number (long, size_t, ...) 2662 */ 2663static noinline_for_stack 2664struct fmt format_decode(struct fmt fmt, struct printf_spec *spec) 2665{ 2666 const char *start = fmt.str; 2667 char flag; 2668 2669 /* we finished early by reading the field width */ 2670 if (unlikely(fmt.state == FORMAT_STATE_WIDTH)) { 2671 if (spec->field_width < 0) { 2672 spec->field_width = -spec->field_width; 2673 spec->flags |= LEFT; 2674 } 2675 fmt.state = FORMAT_STATE_NONE; 2676 goto precision; 2677 } 2678 2679 /* we finished early by reading the precision */ 2680 if (unlikely(fmt.state == FORMAT_STATE_PRECISION)) { 2681 if (spec->precision < 0) 2682 spec->precision = 0; 2683 2684 fmt.state = FORMAT_STATE_NONE; 2685 goto qualifier; 2686 } 2687 2688 /* By default */ 2689 fmt.state = FORMAT_STATE_NONE; 2690 2691 for (; *fmt.str ; fmt.str++) { 2692 if (*fmt.str == '%') 2693 break; 2694 } 2695 2696 /* Return the current non-format string */ 2697 if (fmt.str != start || !*fmt.str) 2698 return fmt; 2699 2700 /* Process flags. This also skips the first '%' */ 2701 spec->flags = 0; 2702 do { 2703 /* this also skips first '%' */ 2704 flag = spec_flag(*++fmt.str); 2705 spec->flags |= flag; 2706 } while (flag); 2707 2708 /* get field width */ 2709 spec->field_width = -1; 2710 2711 if (isdigit(*fmt.str)) 2712 spec->field_width = skip_atoi(&fmt.str); 2713 else if (unlikely(*fmt.str == '*')) { 2714 /* it's the next argument */ 2715 fmt.state = FORMAT_STATE_WIDTH; 2716 fmt.str++; 2717 return fmt; 2718 } 2719 2720precision: 2721 /* get the precision */ 2722 spec->precision = -1; 2723 if (unlikely(*fmt.str == '.')) { 2724 fmt.str++; 2725 if (isdigit(*fmt.str)) { 2726 spec->precision = skip_atoi(&fmt.str); 2727 if (spec->precision < 0) 2728 spec->precision = 0; 2729 } else if (*fmt.str == '*') { 2730 /* it's the next argument */ 2731 fmt.state = FORMAT_STATE_PRECISION; 2732 fmt.str++; 2733 return fmt; 2734 } 2735 } 2736 2737qualifier: 2738 /* Set up default numeric format */ 2739 spec->base = 10; 2740 fmt.state = FORMAT_STATE_NUM; 2741 fmt.size = sizeof(int); 2742 static const struct format_state { 2743 unsigned char state; 2744 unsigned char size; 2745 unsigned char flags_or_double_size; 2746 unsigned char base; 2747 } lookup_state[256] = { 2748 // Length 2749 ['l'] = { 0, sizeof(long), sizeof(long long) }, 2750 ['L'] = { 0, sizeof(long long) }, 2751 ['h'] = { 0, sizeof(short), sizeof(char) }, 2752 ['H'] = { 0, sizeof(char) }, // Questionable historical 2753 ['z'] = { 0, sizeof(size_t) }, 2754 ['t'] = { 0, sizeof(ptrdiff_t) }, 2755 2756 // Non-numeric formats 2757 ['c'] = { FORMAT_STATE_CHAR }, 2758 ['s'] = { FORMAT_STATE_STR }, 2759 ['p'] = { FORMAT_STATE_PTR }, 2760 ['%'] = { FORMAT_STATE_PERCENT_CHAR }, 2761 2762 // Numerics 2763 ['o'] = { FORMAT_STATE_NUM, 0, 0, 8 }, 2764 ['x'] = { FORMAT_STATE_NUM, 0, SMALL, 16 }, 2765 ['X'] = { FORMAT_STATE_NUM, 0, 0, 16 }, 2766 ['d'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2767 ['i'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2768 ['u'] = { FORMAT_STATE_NUM, 0, 0, 10, }, 2769 2770 /* 2771 * Since %n poses a greater security risk than 2772 * utility, treat it as any other invalid or 2773 * unsupported format specifier. 2774 */ 2775 }; 2776 2777 const struct format_state *p = lookup_state + (u8)*fmt.str; 2778 if (p->size) { 2779 fmt.size = p->size; 2780 if (p->flags_or_double_size && fmt.str[0] == fmt.str[1]) { 2781 fmt.size = p->flags_or_double_size; 2782 fmt.str++; 2783 } 2784 fmt.str++; 2785 p = lookup_state + *fmt.str; 2786 } 2787 if (p->state) { 2788 if (p->base) 2789 spec->base = p->base; 2790 spec->flags |= p->flags_or_double_size; 2791 fmt.state = p->state; 2792 fmt.str++; 2793 return fmt; 2794 } 2795 2796 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt.str); 2797 fmt.state = FORMAT_STATE_INVALID; 2798 return fmt; 2799} 2800 2801static void 2802set_field_width(struct printf_spec *spec, int width) 2803{ 2804 spec->field_width = width; 2805 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2806 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2807 } 2808} 2809 2810static void 2811set_precision(struct printf_spec *spec, int prec) 2812{ 2813 spec->precision = prec; 2814 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2815 spec->precision = clamp(prec, 0, PRECISION_MAX); 2816 } 2817} 2818 2819/* 2820 * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate 2821 * as necessary and deal with signedness. 2822 * 2823 * 'size' is the size of the value in bytes. 2824 */ 2825static unsigned long long convert_num_spec(unsigned int val, int size, struct printf_spec spec) 2826{ 2827 unsigned int shift = 32 - size*8; 2828 2829 val <<= shift; 2830 if (!(spec.flags & SIGN)) 2831 return val >> shift; 2832 return (int)val >> shift; 2833} 2834 2835/** 2836 * vsnprintf - Format a string and place it in a buffer 2837 * @buf: The buffer to place the result into 2838 * @size: The size of the buffer, including the trailing null space 2839 * @fmt_str: The format string to use 2840 * @args: Arguments for the format string 2841 * 2842 * This function generally follows C99 vsnprintf, but has some 2843 * extensions and a few limitations: 2844 * 2845 * - ``%n`` is unsupported 2846 * - ``%p*`` is handled by pointer() 2847 * 2848 * See pointer() or Documentation/core-api/printk-formats.rst for more 2849 * extensive description. 2850 * 2851 * **Please update the documentation in both places when making changes** 2852 * 2853 * The return value is the number of characters which would 2854 * be generated for the given input, excluding the trailing 2855 * '\0', as per ISO C99. If you want to have the exact 2856 * number of characters written into @buf as return value 2857 * (not including the trailing '\0'), use vscnprintf(). If the 2858 * return is greater than or equal to @size, the resulting 2859 * string is truncated. 2860 * 2861 * If you're not already dealing with a va_list consider using snprintf(). 2862 */ 2863int vsnprintf(char *buf, size_t size, const char *fmt_str, va_list args) 2864{ 2865 char *str, *end; 2866 struct printf_spec spec = {0}; 2867 struct fmt fmt = { 2868 .str = fmt_str, 2869 .state = FORMAT_STATE_NONE, 2870 }; 2871 2872 /* Reject out-of-range values early. Large positive sizes are 2873 used for unknown buffer sizes. */ 2874 if (WARN_ON_ONCE(size > INT_MAX)) 2875 return 0; 2876 2877 str = buf; 2878 end = buf + size; 2879 2880 /* Make sure end is always >= buf */ 2881 if (end < buf) { 2882 end = ((void *)-1); 2883 size = end - buf; 2884 } 2885 2886 while (*fmt.str) { 2887 const char *old_fmt = fmt.str; 2888 2889 fmt = format_decode(fmt, &spec); 2890 2891 switch (fmt.state) { 2892 case FORMAT_STATE_NONE: { 2893 int read = fmt.str - old_fmt; 2894 if (str < end) { 2895 int copy = read; 2896 if (copy > end - str) 2897 copy = end - str; 2898 memcpy(str, old_fmt, copy); 2899 } 2900 str += read; 2901 continue; 2902 } 2903 2904 case FORMAT_STATE_NUM: { 2905 unsigned long long num; 2906 2907 if (fmt.size > sizeof(int)) 2908 num = va_arg(args, long long); 2909 else 2910 num = convert_num_spec(va_arg(args, int), fmt.size, spec); 2911 str = number(str, end, num, spec); 2912 continue; 2913 } 2914 2915 case FORMAT_STATE_WIDTH: 2916 set_field_width(&spec, va_arg(args, int)); 2917 continue; 2918 2919 case FORMAT_STATE_PRECISION: 2920 set_precision(&spec, va_arg(args, int)); 2921 continue; 2922 2923 case FORMAT_STATE_CHAR: { 2924 char c; 2925 2926 if (!(spec.flags & LEFT)) { 2927 while (--spec.field_width > 0) { 2928 if (str < end) 2929 *str = ' '; 2930 ++str; 2931 2932 } 2933 } 2934 c = (unsigned char) va_arg(args, int); 2935 if (str < end) 2936 *str = c; 2937 ++str; 2938 while (--spec.field_width > 0) { 2939 if (str < end) 2940 *str = ' '; 2941 ++str; 2942 } 2943 continue; 2944 } 2945 2946 case FORMAT_STATE_STR: 2947 str = string(str, end, va_arg(args, char *), spec); 2948 continue; 2949 2950 case FORMAT_STATE_PTR: 2951 str = pointer(fmt.str, str, end, va_arg(args, void *), 2952 spec); 2953 while (isalnum(*fmt.str)) 2954 fmt.str++; 2955 continue; 2956 2957 case FORMAT_STATE_PERCENT_CHAR: 2958 if (str < end) 2959 *str = '%'; 2960 ++str; 2961 continue; 2962 2963 default: 2964 /* 2965 * Presumably the arguments passed gcc's type 2966 * checking, but there is no safe or sane way 2967 * for us to continue parsing the format and 2968 * fetching from the va_list; the remaining 2969 * specifiers and arguments would be out of 2970 * sync. 2971 */ 2972 goto out; 2973 } 2974 } 2975 2976out: 2977 if (size > 0) { 2978 if (str < end) 2979 *str = '\0'; 2980 else 2981 end[-1] = '\0'; 2982 } 2983 2984 /* the trailing null byte doesn't count towards the total */ 2985 return str-buf; 2986 2987} 2988EXPORT_SYMBOL(vsnprintf); 2989 2990/** 2991 * vscnprintf - Format a string and place it in a buffer 2992 * @buf: The buffer to place the result into 2993 * @size: The size of the buffer, including the trailing null space 2994 * @fmt: The format string to use 2995 * @args: Arguments for the format string 2996 * 2997 * The return value is the number of characters which have been written into 2998 * the @buf not including the trailing '\0'. If @size is == 0 the function 2999 * returns 0. 3000 * 3001 * If you're not already dealing with a va_list consider using scnprintf(). 3002 * 3003 * See the vsnprintf() documentation for format string extensions over C99. 3004 */ 3005int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 3006{ 3007 int i; 3008 3009 if (unlikely(!size)) 3010 return 0; 3011 3012 i = vsnprintf(buf, size, fmt, args); 3013 3014 if (likely(i < size)) 3015 return i; 3016 3017 return size - 1; 3018} 3019EXPORT_SYMBOL(vscnprintf); 3020 3021/** 3022 * snprintf - Format a string and place it in a buffer 3023 * @buf: The buffer to place the result into 3024 * @size: The size of the buffer, including the trailing null space 3025 * @fmt: The format string to use 3026 * @...: Arguments for the format string 3027 * 3028 * The return value is the number of characters which would be 3029 * generated for the given input, excluding the trailing null, 3030 * as per ISO C99. If the return is greater than or equal to 3031 * @size, the resulting string is truncated. 3032 * 3033 * See the vsnprintf() documentation for format string extensions over C99. 3034 */ 3035int snprintf(char *buf, size_t size, const char *fmt, ...) 3036{ 3037 va_list args; 3038 int i; 3039 3040 va_start(args, fmt); 3041 i = vsnprintf(buf, size, fmt, args); 3042 va_end(args); 3043 3044 return i; 3045} 3046EXPORT_SYMBOL(snprintf); 3047 3048/** 3049 * scnprintf - Format a string and place it in a buffer 3050 * @buf: The buffer to place the result into 3051 * @size: The size of the buffer, including the trailing null space 3052 * @fmt: The format string to use 3053 * @...: Arguments for the format string 3054 * 3055 * The return value is the number of characters written into @buf not including 3056 * the trailing '\0'. If @size is == 0 the function returns 0. 3057 */ 3058 3059int scnprintf(char *buf, size_t size, const char *fmt, ...) 3060{ 3061 va_list args; 3062 int i; 3063 3064 va_start(args, fmt); 3065 i = vscnprintf(buf, size, fmt, args); 3066 va_end(args); 3067 3068 return i; 3069} 3070EXPORT_SYMBOL(scnprintf); 3071 3072/** 3073 * vsprintf - Format a string and place it in a buffer 3074 * @buf: The buffer to place the result into 3075 * @fmt: The format string to use 3076 * @args: Arguments for the format string 3077 * 3078 * The return value is the number of characters written into @buf not including 3079 * the trailing '\0'. Use vsnprintf() or vscnprintf() in order to avoid 3080 * buffer overflows. 3081 * 3082 * If you're not already dealing with a va_list consider using sprintf(). 3083 * 3084 * See the vsnprintf() documentation for format string extensions over C99. 3085 */ 3086int vsprintf(char *buf, const char *fmt, va_list args) 3087{ 3088 return vsnprintf(buf, INT_MAX, fmt, args); 3089} 3090EXPORT_SYMBOL(vsprintf); 3091 3092/** 3093 * sprintf - Format a string and place it in a buffer 3094 * @buf: The buffer to place the result into 3095 * @fmt: The format string to use 3096 * @...: Arguments for the format string 3097 * 3098 * The return value is the number of characters written into @buf not including 3099 * the trailing '\0'. Use snprintf() or scnprintf() in order to avoid 3100 * buffer overflows. 3101 * 3102 * See the vsnprintf() documentation for format string extensions over C99. 3103 */ 3104int sprintf(char *buf, const char *fmt, ...) 3105{ 3106 va_list args; 3107 int i; 3108 3109 va_start(args, fmt); 3110 i = vsnprintf(buf, INT_MAX, fmt, args); 3111 va_end(args); 3112 3113 return i; 3114} 3115EXPORT_SYMBOL(sprintf); 3116 3117#ifdef CONFIG_BINARY_PRINTF 3118/* 3119 * bprintf service: 3120 * vbin_printf() - VA arguments to binary data 3121 * bstr_printf() - Binary data to text string 3122 */ 3123 3124/** 3125 * vbin_printf - Parse a format string and place args' binary value in a buffer 3126 * @bin_buf: The buffer to place args' binary value 3127 * @size: The size of the buffer(by words(32bits), not characters) 3128 * @fmt_str: The format string to use 3129 * @args: Arguments for the format string 3130 * 3131 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3132 * is skipped. 3133 * 3134 * The return value is the number of words(32bits) which would be generated for 3135 * the given input. 3136 * 3137 * NOTE: 3138 * If the return value is greater than @size, the resulting bin_buf is NOT 3139 * valid for bstr_printf(). 3140 */ 3141int vbin_printf(u32 *bin_buf, size_t size, const char *fmt_str, va_list args) 3142{ 3143 struct fmt fmt = { 3144 .str = fmt_str, 3145 .state = FORMAT_STATE_NONE, 3146 }; 3147 struct printf_spec spec = {0}; 3148 char *str, *end; 3149 int width; 3150 3151 str = (char *)bin_buf; 3152 end = (char *)(bin_buf + size); 3153 3154#define save_arg(type) \ 3155({ \ 3156 unsigned long long value; \ 3157 if (sizeof(type) == 8) { \ 3158 unsigned long long val8; \ 3159 str = PTR_ALIGN(str, sizeof(u32)); \ 3160 val8 = va_arg(args, unsigned long long); \ 3161 if (str + sizeof(type) <= end) { \ 3162 *(u32 *)str = *(u32 *)&val8; \ 3163 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3164 } \ 3165 value = val8; \ 3166 } else { \ 3167 unsigned int val4; \ 3168 str = PTR_ALIGN(str, sizeof(type)); \ 3169 val4 = va_arg(args, int); \ 3170 if (str + sizeof(type) <= end) \ 3171 *(typeof(type) *)str = (type)(long)val4; \ 3172 value = (unsigned long long)val4; \ 3173 } \ 3174 str += sizeof(type); \ 3175 value; \ 3176}) 3177 3178 while (*fmt.str) { 3179 fmt = format_decode(fmt, &spec); 3180 3181 switch (fmt.state) { 3182 case FORMAT_STATE_NONE: 3183 case FORMAT_STATE_PERCENT_CHAR: 3184 break; 3185 case FORMAT_STATE_INVALID: 3186 goto out; 3187 3188 case FORMAT_STATE_WIDTH: 3189 case FORMAT_STATE_PRECISION: 3190 width = (int)save_arg(int); 3191 /* Pointers may require the width */ 3192 if (*fmt.str == 'p') 3193 set_field_width(&spec, width); 3194 break; 3195 3196 case FORMAT_STATE_CHAR: 3197 save_arg(char); 3198 break; 3199 3200 case FORMAT_STATE_STR: { 3201 const char *save_str = va_arg(args, char *); 3202 const char *err_msg; 3203 size_t len; 3204 3205 err_msg = check_pointer_msg(save_str); 3206 if (err_msg) 3207 save_str = err_msg; 3208 3209 len = strlen(save_str) + 1; 3210 if (str + len < end) 3211 memcpy(str, save_str, len); 3212 str += len; 3213 break; 3214 } 3215 3216 case FORMAT_STATE_PTR: 3217 /* Dereferenced pointers must be done now */ 3218 switch (*fmt.str) { 3219 /* Dereference of functions is still OK */ 3220 case 'S': 3221 case 's': 3222 case 'x': 3223 case 'K': 3224 case 'e': 3225 save_arg(void *); 3226 break; 3227 default: 3228 if (!isalnum(*fmt.str)) { 3229 save_arg(void *); 3230 break; 3231 } 3232 str = pointer(fmt.str, str, end, va_arg(args, void *), 3233 spec); 3234 if (str + 1 < end) 3235 *str++ = '\0'; 3236 else 3237 end[-1] = '\0'; /* Must be nul terminated */ 3238 } 3239 /* skip all alphanumeric pointer suffixes */ 3240 while (isalnum(*fmt.str)) 3241 fmt.str++; 3242 break; 3243 3244 case FORMAT_STATE_NUM: 3245 if (fmt.size > sizeof(int)) { 3246 save_arg(long long); 3247 } else { 3248 save_arg(int); 3249 } 3250 } 3251 } 3252 3253out: 3254 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3255#undef save_arg 3256} 3257EXPORT_SYMBOL_GPL(vbin_printf); 3258 3259/** 3260 * bstr_printf - Format a string from binary arguments and place it in a buffer 3261 * @buf: The buffer to place the result into 3262 * @size: The size of the buffer, including the trailing null space 3263 * @fmt_str: The format string to use 3264 * @bin_buf: Binary arguments for the format string 3265 * 3266 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3267 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3268 * a binary buffer that generated by vbin_printf. 3269 * 3270 * The format follows C99 vsnprintf, but has some extensions: 3271 * see vsnprintf comment for details. 3272 * 3273 * The return value is the number of characters which would 3274 * be generated for the given input, excluding the trailing 3275 * '\0', as per ISO C99. If you want to have the exact 3276 * number of characters written into @buf as return value 3277 * (not including the trailing '\0'), use vscnprintf(). If the 3278 * return is greater than or equal to @size, the resulting 3279 * string is truncated. 3280 */ 3281int bstr_printf(char *buf, size_t size, const char *fmt_str, const u32 *bin_buf) 3282{ 3283 struct fmt fmt = { 3284 .str = fmt_str, 3285 .state = FORMAT_STATE_NONE, 3286 }; 3287 struct printf_spec spec = {0}; 3288 char *str, *end; 3289 const char *args = (const char *)bin_buf; 3290 3291 if (WARN_ON_ONCE(size > INT_MAX)) 3292 return 0; 3293 3294 str = buf; 3295 end = buf + size; 3296 3297#define get_arg(type) \ 3298({ \ 3299 typeof(type) value; \ 3300 if (sizeof(type) == 8) { \ 3301 args = PTR_ALIGN(args, sizeof(u32)); \ 3302 *(u32 *)&value = *(u32 *)args; \ 3303 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3304 } else { \ 3305 args = PTR_ALIGN(args, sizeof(type)); \ 3306 value = *(typeof(type) *)args; \ 3307 } \ 3308 args += sizeof(type); \ 3309 value; \ 3310}) 3311 3312 /* Make sure end is always >= buf */ 3313 if (end < buf) { 3314 end = ((void *)-1); 3315 size = end - buf; 3316 } 3317 3318 while (*fmt.str) { 3319 const char *old_fmt = fmt.str; 3320 unsigned long long num; 3321 3322 fmt = format_decode(fmt, &spec); 3323 switch (fmt.state) { 3324 case FORMAT_STATE_NONE: { 3325 int read = fmt.str - old_fmt; 3326 if (str < end) { 3327 int copy = read; 3328 if (copy > end - str) 3329 copy = end - str; 3330 memcpy(str, old_fmt, copy); 3331 } 3332 str += read; 3333 continue; 3334 } 3335 3336 case FORMAT_STATE_WIDTH: 3337 set_field_width(&spec, get_arg(int)); 3338 continue; 3339 3340 case FORMAT_STATE_PRECISION: 3341 set_precision(&spec, get_arg(int)); 3342 continue; 3343 3344 case FORMAT_STATE_CHAR: { 3345 char c; 3346 3347 if (!(spec.flags & LEFT)) { 3348 while (--spec.field_width > 0) { 3349 if (str < end) 3350 *str = ' '; 3351 ++str; 3352 } 3353 } 3354 c = (unsigned char) get_arg(char); 3355 if (str < end) 3356 *str = c; 3357 ++str; 3358 while (--spec.field_width > 0) { 3359 if (str < end) 3360 *str = ' '; 3361 ++str; 3362 } 3363 continue; 3364 } 3365 3366 case FORMAT_STATE_STR: { 3367 const char *str_arg = args; 3368 args += strlen(str_arg) + 1; 3369 str = string(str, end, (char *)str_arg, spec); 3370 continue; 3371 } 3372 3373 case FORMAT_STATE_PTR: { 3374 bool process = false; 3375 int copy, len; 3376 /* Non function dereferences were already done */ 3377 switch (*fmt.str) { 3378 case 'S': 3379 case 's': 3380 case 'x': 3381 case 'K': 3382 case 'e': 3383 process = true; 3384 break; 3385 default: 3386 if (!isalnum(*fmt.str)) { 3387 process = true; 3388 break; 3389 } 3390 /* Pointer dereference was already processed */ 3391 if (str < end) { 3392 len = copy = strlen(args); 3393 if (copy > end - str) 3394 copy = end - str; 3395 memcpy(str, args, copy); 3396 str += len; 3397 args += len + 1; 3398 } 3399 } 3400 if (process) 3401 str = pointer(fmt.str, str, end, get_arg(void *), spec); 3402 3403 while (isalnum(*fmt.str)) 3404 fmt.str++; 3405 continue; 3406 } 3407 3408 case FORMAT_STATE_PERCENT_CHAR: 3409 if (str < end) 3410 *str = '%'; 3411 ++str; 3412 continue; 3413 3414 case FORMAT_STATE_INVALID: 3415 goto out; 3416 3417 case FORMAT_STATE_NUM: 3418 if (fmt.size > sizeof(int)) 3419 num = get_arg(long long); 3420 else 3421 num = convert_num_spec(get_arg(int), fmt.size, spec); 3422 str = number(str, end, num, spec); 3423 continue; 3424 } 3425 } /* while(*fmt.str) */ 3426 3427out: 3428 if (size > 0) { 3429 if (str < end) 3430 *str = '\0'; 3431 else 3432 end[-1] = '\0'; 3433 } 3434 3435#undef get_arg 3436 3437 /* the trailing null byte doesn't count towards the total */ 3438 return str - buf; 3439} 3440EXPORT_SYMBOL_GPL(bstr_printf); 3441 3442#endif /* CONFIG_BINARY_PRINTF */ 3443 3444/** 3445 * vsscanf - Unformat a buffer into a list of arguments 3446 * @buf: input buffer 3447 * @fmt: format of buffer 3448 * @args: arguments 3449 */ 3450int vsscanf(const char *buf, const char *fmt, va_list args) 3451{ 3452 const char *str = buf; 3453 char *next; 3454 char digit; 3455 int num = 0; 3456 u8 qualifier; 3457 unsigned int base; 3458 union { 3459 long long s; 3460 unsigned long long u; 3461 } val; 3462 s16 field_width; 3463 bool is_sign; 3464 3465 while (*fmt) { 3466 /* skip any white space in format */ 3467 /* white space in format matches any amount of 3468 * white space, including none, in the input. 3469 */ 3470 if (isspace(*fmt)) { 3471 fmt = skip_spaces(++fmt); 3472 str = skip_spaces(str); 3473 } 3474 3475 /* anything that is not a conversion must match exactly */ 3476 if (*fmt != '%' && *fmt) { 3477 if (*fmt++ != *str++) 3478 break; 3479 continue; 3480 } 3481 3482 if (!*fmt) 3483 break; 3484 ++fmt; 3485 3486 /* skip this conversion. 3487 * advance both strings to next white space 3488 */ 3489 if (*fmt == '*') { 3490 if (!*str) 3491 break; 3492 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3493 /* '%*[' not yet supported, invalid format */ 3494 if (*fmt == '[') 3495 return num; 3496 fmt++; 3497 } 3498 while (!isspace(*str) && *str) 3499 str++; 3500 continue; 3501 } 3502 3503 /* get field width */ 3504 field_width = -1; 3505 if (isdigit(*fmt)) { 3506 field_width = skip_atoi(&fmt); 3507 if (field_width <= 0) 3508 break; 3509 } 3510 3511 /* get conversion qualifier */ 3512 qualifier = -1; 3513 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3514 *fmt == 'z') { 3515 qualifier = *fmt++; 3516 if (unlikely(qualifier == *fmt)) { 3517 if (qualifier == 'h') { 3518 qualifier = 'H'; 3519 fmt++; 3520 } else if (qualifier == 'l') { 3521 qualifier = 'L'; 3522 fmt++; 3523 } 3524 } 3525 } 3526 3527 if (!*fmt) 3528 break; 3529 3530 if (*fmt == 'n') { 3531 /* return number of characters read so far */ 3532 *va_arg(args, int *) = str - buf; 3533 ++fmt; 3534 continue; 3535 } 3536 3537 if (!*str) 3538 break; 3539 3540 base = 10; 3541 is_sign = false; 3542 3543 switch (*fmt++) { 3544 case 'c': 3545 { 3546 char *s = (char *)va_arg(args, char*); 3547 if (field_width == -1) 3548 field_width = 1; 3549 do { 3550 *s++ = *str++; 3551 } while (--field_width > 0 && *str); 3552 num++; 3553 } 3554 continue; 3555 case 's': 3556 { 3557 char *s = (char *)va_arg(args, char *); 3558 if (field_width == -1) 3559 field_width = SHRT_MAX; 3560 /* first, skip leading white space in buffer */ 3561 str = skip_spaces(str); 3562 3563 /* now copy until next white space */ 3564 while (*str && !isspace(*str) && field_width--) 3565 *s++ = *str++; 3566 *s = '\0'; 3567 num++; 3568 } 3569 continue; 3570 /* 3571 * Warning: This implementation of the '[' conversion specifier 3572 * deviates from its glibc counterpart in the following ways: 3573 * (1) It does NOT support ranges i.e. '-' is NOT a special 3574 * character 3575 * (2) It cannot match the closing bracket ']' itself 3576 * (3) A field width is required 3577 * (4) '%*[' (discard matching input) is currently not supported 3578 * 3579 * Example usage: 3580 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3581 * buf1, buf2, buf3); 3582 * if (ret < 3) 3583 * // etc.. 3584 */ 3585 case '[': 3586 { 3587 char *s = (char *)va_arg(args, char *); 3588 DECLARE_BITMAP(set, 256) = {0}; 3589 unsigned int len = 0; 3590 bool negate = (*fmt == '^'); 3591 3592 /* field width is required */ 3593 if (field_width == -1) 3594 return num; 3595 3596 if (negate) 3597 ++fmt; 3598 3599 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3600 __set_bit((u8)*fmt, set); 3601 3602 /* no ']' or no character set found */ 3603 if (!*fmt || !len) 3604 return num; 3605 ++fmt; 3606 3607 if (negate) { 3608 bitmap_complement(set, set, 256); 3609 /* exclude null '\0' byte */ 3610 __clear_bit(0, set); 3611 } 3612 3613 /* match must be non-empty */ 3614 if (!test_bit((u8)*str, set)) 3615 return num; 3616 3617 while (test_bit((u8)*str, set) && field_width--) 3618 *s++ = *str++; 3619 *s = '\0'; 3620 ++num; 3621 } 3622 continue; 3623 case 'o': 3624 base = 8; 3625 break; 3626 case 'x': 3627 case 'X': 3628 base = 16; 3629 break; 3630 case 'i': 3631 base = 0; 3632 fallthrough; 3633 case 'd': 3634 is_sign = true; 3635 fallthrough; 3636 case 'u': 3637 break; 3638 case '%': 3639 /* looking for '%' in str */ 3640 if (*str++ != '%') 3641 return num; 3642 continue; 3643 default: 3644 /* invalid format; stop here */ 3645 return num; 3646 } 3647 3648 /* have some sort of integer conversion. 3649 * first, skip white space in buffer. 3650 */ 3651 str = skip_spaces(str); 3652 3653 digit = *str; 3654 if (is_sign && digit == '-') { 3655 if (field_width == 1) 3656 break; 3657 3658 digit = *(str + 1); 3659 } 3660 3661 if (!digit 3662 || (base == 16 && !isxdigit(digit)) 3663 || (base == 10 && !isdigit(digit)) 3664 || (base == 8 && !isodigit(digit)) 3665 || (base == 0 && !isdigit(digit))) 3666 break; 3667 3668 if (is_sign) 3669 val.s = simple_strntoll(str, &next, base, 3670 field_width >= 0 ? field_width : INT_MAX); 3671 else 3672 val.u = simple_strntoull(str, &next, base, 3673 field_width >= 0 ? field_width : INT_MAX); 3674 3675 switch (qualifier) { 3676 case 'H': /* that's 'hh' in format */ 3677 if (is_sign) 3678 *va_arg(args, signed char *) = val.s; 3679 else 3680 *va_arg(args, unsigned char *) = val.u; 3681 break; 3682 case 'h': 3683 if (is_sign) 3684 *va_arg(args, short *) = val.s; 3685 else 3686 *va_arg(args, unsigned short *) = val.u; 3687 break; 3688 case 'l': 3689 if (is_sign) 3690 *va_arg(args, long *) = val.s; 3691 else 3692 *va_arg(args, unsigned long *) = val.u; 3693 break; 3694 case 'L': 3695 if (is_sign) 3696 *va_arg(args, long long *) = val.s; 3697 else 3698 *va_arg(args, unsigned long long *) = val.u; 3699 break; 3700 case 'z': 3701 *va_arg(args, size_t *) = val.u; 3702 break; 3703 default: 3704 if (is_sign) 3705 *va_arg(args, int *) = val.s; 3706 else 3707 *va_arg(args, unsigned int *) = val.u; 3708 break; 3709 } 3710 num++; 3711 3712 if (!next) 3713 break; 3714 str = next; 3715 } 3716 3717 return num; 3718} 3719EXPORT_SYMBOL(vsscanf); 3720 3721/** 3722 * sscanf - Unformat a buffer into a list of arguments 3723 * @buf: input buffer 3724 * @fmt: formatting of buffer 3725 * @...: resulting arguments 3726 */ 3727int sscanf(const char *buf, const char *fmt, ...) 3728{ 3729 va_list args; 3730 int i; 3731 3732 va_start(args, fmt); 3733 i = vsscanf(buf, fmt, args); 3734 va_end(args); 3735 3736 return i; 3737} 3738EXPORT_SYMBOL(sscanf);
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