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 <stdarg.h> 21#include <linux/build_bug.h> 22#include <linux/clk.h> 23#include <linux/clk-provider.h> 24#include <linux/errname.h> 25#include <linux/module.h> /* for KSYM_SYMBOL_LEN */ 26#include <linux/types.h> 27#include <linux/string.h> 28#include <linux/ctype.h> 29#include <linux/kernel.h> 30#include <linux/kallsyms.h> 31#include <linux/math64.h> 32#include <linux/uaccess.h> 33#include <linux/ioport.h> 34#include <linux/dcache.h> 35#include <linux/cred.h> 36#include <linux/rtc.h> 37#include <linux/time.h> 38#include <linux/uuid.h> 39#include <linux/of.h> 40#include <net/addrconf.h> 41#include <linux/siphash.h> 42#include <linux/compiler.h> 43#include <linux/property.h> 44#ifdef CONFIG_BLOCK 45#include <linux/blkdev.h> 46#endif 47 48#include "../mm/internal.h" /* For the trace_print_flags arrays */ 49 50#include <asm/page.h> /* for PAGE_SIZE */ 51#include <asm/byteorder.h> /* cpu_to_le16 */ 52 53#include <linux/string_helpers.h> 54#include "kstrtox.h" 55 56static unsigned long long simple_strntoull(const char *startp, size_t max_chars, 57 char **endp, unsigned int base) 58{ 59 const char *cp; 60 unsigned long long result = 0ULL; 61 size_t prefix_chars; 62 unsigned int rv; 63 64 cp = _parse_integer_fixup_radix(startp, &base); 65 prefix_chars = cp - startp; 66 if (prefix_chars < max_chars) { 67 rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); 68 /* FIXME */ 69 cp += (rv & ~KSTRTOX_OVERFLOW); 70 } else { 71 /* Field too short for prefix + digit, skip over without converting */ 72 cp = startp + max_chars; 73 } 74 75 if (endp) 76 *endp = (char *)cp; 77 78 return result; 79} 80 81/** 82 * simple_strtoull - convert a string to an unsigned long long 83 * @cp: The start of the string 84 * @endp: A pointer to the end of the parsed string will be placed here 85 * @base: The number base to use 86 * 87 * This function has caveats. Please use kstrtoull instead. 88 */ 89unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 90{ 91 return simple_strntoull(cp, INT_MAX, endp, base); 92} 93EXPORT_SYMBOL(simple_strtoull); 94 95/** 96 * simple_strtoul - convert a string to an unsigned long 97 * @cp: The start of the string 98 * @endp: A pointer to the end of the parsed string will be placed here 99 * @base: The number base to use 100 * 101 * This function has caveats. Please use kstrtoul instead. 102 */ 103unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 104{ 105 return simple_strtoull(cp, endp, base); 106} 107EXPORT_SYMBOL(simple_strtoul); 108 109/** 110 * simple_strtol - convert a string to a signed long 111 * @cp: The start of the string 112 * @endp: A pointer to the end of the parsed string will be placed here 113 * @base: The number base to use 114 * 115 * This function has caveats. Please use kstrtol instead. 116 */ 117long simple_strtol(const char *cp, char **endp, unsigned int base) 118{ 119 if (*cp == '-') 120 return -simple_strtoul(cp + 1, endp, base); 121 122 return simple_strtoul(cp, endp, base); 123} 124EXPORT_SYMBOL(simple_strtol); 125 126static long long simple_strntoll(const char *cp, size_t max_chars, char **endp, 127 unsigned int base) 128{ 129 /* 130 * simple_strntoull() safely handles receiving max_chars==0 in the 131 * case cp[0] == '-' && max_chars == 1. 132 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 133 * and the content of *cp is irrelevant. 134 */ 135 if (*cp == '-' && max_chars > 0) 136 return -simple_strntoull(cp + 1, max_chars - 1, endp, base); 137 138 return simple_strntoull(cp, max_chars, endp, base); 139} 140 141/** 142 * simple_strtoll - convert a string to a signed long long 143 * @cp: The start of the string 144 * @endp: A pointer to the end of the parsed string will be placed here 145 * @base: The number base to use 146 * 147 * This function has caveats. Please use kstrtoll instead. 148 */ 149long long simple_strtoll(const char *cp, char **endp, unsigned int base) 150{ 151 return simple_strntoll(cp, INT_MAX, endp, base); 152} 153EXPORT_SYMBOL(simple_strtoll); 154 155static noinline_for_stack 156int skip_atoi(const char **s) 157{ 158 int i = 0; 159 160 do { 161 i = i*10 + *((*s)++) - '0'; 162 } while (isdigit(**s)); 163 164 return i; 165} 166 167/* 168 * Decimal conversion is by far the most typical, and is used for 169 * /proc and /sys data. This directly impacts e.g. top performance 170 * with many processes running. We optimize it for speed by emitting 171 * two characters at a time, using a 200 byte lookup table. This 172 * roughly halves the number of multiplications compared to computing 173 * the digits one at a time. Implementation strongly inspired by the 174 * previous version, which in turn used ideas described at 175 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 176 * from the author, Douglas W. Jones). 177 * 178 * It turns out there is precisely one 26 bit fixed-point 179 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 180 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 181 * range happens to be somewhat larger (x <= 1073741898), but that's 182 * irrelevant for our purpose. 183 * 184 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 185 * need a 32x32->64 bit multiply, so we simply use the same constant. 186 * 187 * For dividing a number in the range [100, 10^4-1] by 100, there are 188 * several options. The simplest is (x * 0x147b) >> 19, which is valid 189 * for all x <= 43698. 190 */ 191 192static const u16 decpair[100] = { 193#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 194 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 195 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 196 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 197 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 198 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 199 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 200 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 201 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 202 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 203 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 204#undef _ 205}; 206 207/* 208 * This will print a single '0' even if r == 0, since we would 209 * immediately jump to out_r where two 0s would be written but only 210 * one of them accounted for in buf. This is needed by ip4_string 211 * below. All other callers pass a non-zero value of r. 212*/ 213static noinline_for_stack 214char *put_dec_trunc8(char *buf, unsigned r) 215{ 216 unsigned q; 217 218 /* 1 <= r < 10^8 */ 219 if (r < 100) 220 goto out_r; 221 222 /* 100 <= r < 10^8 */ 223 q = (r * (u64)0x28f5c29) >> 32; 224 *((u16 *)buf) = decpair[r - 100*q]; 225 buf += 2; 226 227 /* 1 <= q < 10^6 */ 228 if (q < 100) 229 goto out_q; 230 231 /* 100 <= q < 10^6 */ 232 r = (q * (u64)0x28f5c29) >> 32; 233 *((u16 *)buf) = decpair[q - 100*r]; 234 buf += 2; 235 236 /* 1 <= r < 10^4 */ 237 if (r < 100) 238 goto out_r; 239 240 /* 100 <= r < 10^4 */ 241 q = (r * 0x147b) >> 19; 242 *((u16 *)buf) = decpair[r - 100*q]; 243 buf += 2; 244out_q: 245 /* 1 <= q < 100 */ 246 r = q; 247out_r: 248 /* 1 <= r < 100 */ 249 *((u16 *)buf) = decpair[r]; 250 buf += r < 10 ? 1 : 2; 251 return buf; 252} 253 254#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 255static noinline_for_stack 256char *put_dec_full8(char *buf, unsigned r) 257{ 258 unsigned q; 259 260 /* 0 <= r < 10^8 */ 261 q = (r * (u64)0x28f5c29) >> 32; 262 *((u16 *)buf) = decpair[r - 100*q]; 263 buf += 2; 264 265 /* 0 <= q < 10^6 */ 266 r = (q * (u64)0x28f5c29) >> 32; 267 *((u16 *)buf) = decpair[q - 100*r]; 268 buf += 2; 269 270 /* 0 <= r < 10^4 */ 271 q = (r * 0x147b) >> 19; 272 *((u16 *)buf) = decpair[r - 100*q]; 273 buf += 2; 274 275 /* 0 <= q < 100 */ 276 *((u16 *)buf) = decpair[q]; 277 buf += 2; 278 return buf; 279} 280 281static noinline_for_stack 282char *put_dec(char *buf, unsigned long long n) 283{ 284 if (n >= 100*1000*1000) 285 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 286 /* 1 <= n <= 1.6e11 */ 287 if (n >= 100*1000*1000) 288 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 289 /* 1 <= n < 1e8 */ 290 return put_dec_trunc8(buf, n); 291} 292 293#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 294 295static void 296put_dec_full4(char *buf, unsigned r) 297{ 298 unsigned q; 299 300 /* 0 <= r < 10^4 */ 301 q = (r * 0x147b) >> 19; 302 *((u16 *)buf) = decpair[r - 100*q]; 303 buf += 2; 304 /* 0 <= q < 100 */ 305 *((u16 *)buf) = decpair[q]; 306} 307 308/* 309 * Call put_dec_full4 on x % 10000, return x / 10000. 310 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 311 * holds for all x < 1,128,869,999. The largest value this 312 * helper will ever be asked to convert is 1,125,520,955. 313 * (second call in the put_dec code, assuming n is all-ones). 314 */ 315static noinline_for_stack 316unsigned put_dec_helper4(char *buf, unsigned x) 317{ 318 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 319 320 put_dec_full4(buf, x - q * 10000); 321 return q; 322} 323 324/* Based on code by Douglas W. Jones found at 325 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 326 * (with permission from the author). 327 * Performs no 64-bit division and hence should be fast on 32-bit machines. 328 */ 329static 330char *put_dec(char *buf, unsigned long long n) 331{ 332 uint32_t d3, d2, d1, q, h; 333 334 if (n < 100*1000*1000) 335 return put_dec_trunc8(buf, n); 336 337 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 338 h = (n >> 32); 339 d2 = (h ) & 0xffff; 340 d3 = (h >> 16); /* implicit "& 0xffff" */ 341 342 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 343 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 344 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 345 q = put_dec_helper4(buf, q); 346 347 q += 7671 * d3 + 9496 * d2 + 6 * d1; 348 q = put_dec_helper4(buf+4, q); 349 350 q += 4749 * d3 + 42 * d2; 351 q = put_dec_helper4(buf+8, q); 352 353 q += 281 * d3; 354 buf += 12; 355 if (q) 356 buf = put_dec_trunc8(buf, q); 357 else while (buf[-1] == '0') 358 --buf; 359 360 return buf; 361} 362 363#endif 364 365/* 366 * Convert passed number to decimal string. 367 * Returns the length of string. On buffer overflow, returns 0. 368 * 369 * If speed is not important, use snprintf(). It's easy to read the code. 370 */ 371int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 372{ 373 /* put_dec requires 2-byte alignment of the buffer. */ 374 char tmp[sizeof(num) * 3] __aligned(2); 375 int idx, len; 376 377 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 378 if (num <= 9) { 379 tmp[0] = '0' + num; 380 len = 1; 381 } else { 382 len = put_dec(tmp, num) - tmp; 383 } 384 385 if (len > size || width > size) 386 return 0; 387 388 if (width > len) { 389 width = width - len; 390 for (idx = 0; idx < width; idx++) 391 buf[idx] = ' '; 392 } else { 393 width = 0; 394 } 395 396 for (idx = 0; idx < len; ++idx) 397 buf[idx + width] = tmp[len - idx - 1]; 398 399 return len + width; 400} 401 402#define SIGN 1 /* unsigned/signed, must be 1 */ 403#define LEFT 2 /* left justified */ 404#define PLUS 4 /* show plus */ 405#define SPACE 8 /* space if plus */ 406#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 407#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 408#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 409 410static_assert(ZEROPAD == ('0' - ' ')); 411static_assert(SMALL == ' '); 412 413enum format_type { 414 FORMAT_TYPE_NONE, /* Just a string part */ 415 FORMAT_TYPE_WIDTH, 416 FORMAT_TYPE_PRECISION, 417 FORMAT_TYPE_CHAR, 418 FORMAT_TYPE_STR, 419 FORMAT_TYPE_PTR, 420 FORMAT_TYPE_PERCENT_CHAR, 421 FORMAT_TYPE_INVALID, 422 FORMAT_TYPE_LONG_LONG, 423 FORMAT_TYPE_ULONG, 424 FORMAT_TYPE_LONG, 425 FORMAT_TYPE_UBYTE, 426 FORMAT_TYPE_BYTE, 427 FORMAT_TYPE_USHORT, 428 FORMAT_TYPE_SHORT, 429 FORMAT_TYPE_UINT, 430 FORMAT_TYPE_INT, 431 FORMAT_TYPE_SIZE_T, 432 FORMAT_TYPE_PTRDIFF 433}; 434 435struct printf_spec { 436 unsigned int type:8; /* format_type enum */ 437 signed int field_width:24; /* width of output field */ 438 unsigned int flags:8; /* flags to number() */ 439 unsigned int base:8; /* number base, 8, 10 or 16 only */ 440 signed int precision:16; /* # of digits/chars */ 441} __packed; 442static_assert(sizeof(struct printf_spec) == 8); 443 444#define FIELD_WIDTH_MAX ((1 << 23) - 1) 445#define PRECISION_MAX ((1 << 15) - 1) 446 447static noinline_for_stack 448char *number(char *buf, char *end, unsigned long long num, 449 struct printf_spec spec) 450{ 451 /* put_dec requires 2-byte alignment of the buffer. */ 452 char tmp[3 * sizeof(num)] __aligned(2); 453 char sign; 454 char locase; 455 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 456 int i; 457 bool is_zero = num == 0LL; 458 int field_width = spec.field_width; 459 int precision = spec.precision; 460 461 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 462 * produces same digits or (maybe lowercased) letters */ 463 locase = (spec.flags & SMALL); 464 if (spec.flags & LEFT) 465 spec.flags &= ~ZEROPAD; 466 sign = 0; 467 if (spec.flags & SIGN) { 468 if ((signed long long)num < 0) { 469 sign = '-'; 470 num = -(signed long long)num; 471 field_width--; 472 } else if (spec.flags & PLUS) { 473 sign = '+'; 474 field_width--; 475 } else if (spec.flags & SPACE) { 476 sign = ' '; 477 field_width--; 478 } 479 } 480 if (need_pfx) { 481 if (spec.base == 16) 482 field_width -= 2; 483 else if (!is_zero) 484 field_width--; 485 } 486 487 /* generate full string in tmp[], in reverse order */ 488 i = 0; 489 if (num < spec.base) 490 tmp[i++] = hex_asc_upper[num] | locase; 491 else if (spec.base != 10) { /* 8 or 16 */ 492 int mask = spec.base - 1; 493 int shift = 3; 494 495 if (spec.base == 16) 496 shift = 4; 497 do { 498 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 499 num >>= shift; 500 } while (num); 501 } else { /* base 10 */ 502 i = put_dec(tmp, num) - tmp; 503 } 504 505 /* printing 100 using %2d gives "100", not "00" */ 506 if (i > precision) 507 precision = i; 508 /* leading space padding */ 509 field_width -= precision; 510 if (!(spec.flags & (ZEROPAD | LEFT))) { 511 while (--field_width >= 0) { 512 if (buf < end) 513 *buf = ' '; 514 ++buf; 515 } 516 } 517 /* sign */ 518 if (sign) { 519 if (buf < end) 520 *buf = sign; 521 ++buf; 522 } 523 /* "0x" / "0" prefix */ 524 if (need_pfx) { 525 if (spec.base == 16 || !is_zero) { 526 if (buf < end) 527 *buf = '0'; 528 ++buf; 529 } 530 if (spec.base == 16) { 531 if (buf < end) 532 *buf = ('X' | locase); 533 ++buf; 534 } 535 } 536 /* zero or space padding */ 537 if (!(spec.flags & LEFT)) { 538 char c = ' ' + (spec.flags & ZEROPAD); 539 540 while (--field_width >= 0) { 541 if (buf < end) 542 *buf = c; 543 ++buf; 544 } 545 } 546 /* hmm even more zero padding? */ 547 while (i <= --precision) { 548 if (buf < end) 549 *buf = '0'; 550 ++buf; 551 } 552 /* actual digits of result */ 553 while (--i >= 0) { 554 if (buf < end) 555 *buf = tmp[i]; 556 ++buf; 557 } 558 /* trailing space padding */ 559 while (--field_width >= 0) { 560 if (buf < end) 561 *buf = ' '; 562 ++buf; 563 } 564 565 return buf; 566} 567 568static noinline_for_stack 569char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 570{ 571 struct printf_spec spec; 572 573 spec.type = FORMAT_TYPE_PTR; 574 spec.field_width = 2 + 2 * size; /* 0x + hex */ 575 spec.flags = SPECIAL | SMALL | ZEROPAD; 576 spec.base = 16; 577 spec.precision = -1; 578 579 return number(buf, end, num, spec); 580} 581 582static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 583{ 584 size_t size; 585 if (buf >= end) /* nowhere to put anything */ 586 return; 587 size = end - buf; 588 if (size <= spaces) { 589 memset(buf, ' ', size); 590 return; 591 } 592 if (len) { 593 if (len > size - spaces) 594 len = size - spaces; 595 memmove(buf + spaces, buf, len); 596 } 597 memset(buf, ' ', spaces); 598} 599 600/* 601 * Handle field width padding for a string. 602 * @buf: current buffer position 603 * @n: length of string 604 * @end: end of output buffer 605 * @spec: for field width and flags 606 * Returns: new buffer position after padding. 607 */ 608static noinline_for_stack 609char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 610{ 611 unsigned spaces; 612 613 if (likely(n >= spec.field_width)) 614 return buf; 615 /* we want to pad the sucker */ 616 spaces = spec.field_width - n; 617 if (!(spec.flags & LEFT)) { 618 move_right(buf - n, end, n, spaces); 619 return buf + spaces; 620 } 621 while (spaces--) { 622 if (buf < end) 623 *buf = ' '; 624 ++buf; 625 } 626 return buf; 627} 628 629/* Handle string from a well known address. */ 630static char *string_nocheck(char *buf, char *end, const char *s, 631 struct printf_spec spec) 632{ 633 int len = 0; 634 int lim = spec.precision; 635 636 while (lim--) { 637 char c = *s++; 638 if (!c) 639 break; 640 if (buf < end) 641 *buf = c; 642 ++buf; 643 ++len; 644 } 645 return widen_string(buf, len, end, spec); 646} 647 648static char *err_ptr(char *buf, char *end, void *ptr, 649 struct printf_spec spec) 650{ 651 int err = PTR_ERR(ptr); 652 const char *sym = errname(err); 653 654 if (sym) 655 return string_nocheck(buf, end, sym, spec); 656 657 /* 658 * Somebody passed ERR_PTR(-1234) or some other non-existing 659 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 660 * printing it as its decimal representation. 661 */ 662 spec.flags |= SIGN; 663 spec.base = 10; 664 return number(buf, end, err, spec); 665} 666 667/* Be careful: error messages must fit into the given buffer. */ 668static char *error_string(char *buf, char *end, const char *s, 669 struct printf_spec spec) 670{ 671 /* 672 * Hard limit to avoid a completely insane messages. It actually 673 * works pretty well because most error messages are in 674 * the many pointer format modifiers. 675 */ 676 if (spec.precision == -1) 677 spec.precision = 2 * sizeof(void *); 678 679 return string_nocheck(buf, end, s, spec); 680} 681 682/* 683 * Do not call any complex external code here. Nested printk()/vsprintf() 684 * might cause infinite loops. Failures might break printk() and would 685 * be hard to debug. 686 */ 687static const char *check_pointer_msg(const void *ptr) 688{ 689 if (!ptr) 690 return "(null)"; 691 692 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 693 return "(efault)"; 694 695 return NULL; 696} 697 698static int check_pointer(char **buf, char *end, const void *ptr, 699 struct printf_spec spec) 700{ 701 const char *err_msg; 702 703 err_msg = check_pointer_msg(ptr); 704 if (err_msg) { 705 *buf = error_string(*buf, end, err_msg, spec); 706 return -EFAULT; 707 } 708 709 return 0; 710} 711 712static noinline_for_stack 713char *string(char *buf, char *end, const char *s, 714 struct printf_spec spec) 715{ 716 if (check_pointer(&buf, end, s, spec)) 717 return buf; 718 719 return string_nocheck(buf, end, s, spec); 720} 721 722static char *pointer_string(char *buf, char *end, 723 const void *ptr, 724 struct printf_spec spec) 725{ 726 spec.base = 16; 727 spec.flags |= SMALL; 728 if (spec.field_width == -1) { 729 spec.field_width = 2 * sizeof(ptr); 730 spec.flags |= ZEROPAD; 731 } 732 733 return number(buf, end, (unsigned long int)ptr, spec); 734} 735 736/* Make pointers available for printing early in the boot sequence. */ 737static int debug_boot_weak_hash __ro_after_init; 738 739static int __init debug_boot_weak_hash_enable(char *str) 740{ 741 debug_boot_weak_hash = 1; 742 pr_info("debug_boot_weak_hash enabled\n"); 743 return 0; 744} 745early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 746 747static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key); 748static siphash_key_t ptr_key __read_mostly; 749 750static void enable_ptr_key_workfn(struct work_struct *work) 751{ 752 get_random_bytes(&ptr_key, sizeof(ptr_key)); 753 /* Needs to run from preemptible context */ 754 static_branch_disable(¬_filled_random_ptr_key); 755} 756 757static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); 758 759static int fill_random_ptr_key(struct notifier_block *nb, 760 unsigned long action, void *data) 761{ 762 /* This may be in an interrupt handler. */ 763 queue_work(system_unbound_wq, &enable_ptr_key_work); 764 return 0; 765} 766 767static struct notifier_block random_ready = { 768 .notifier_call = fill_random_ptr_key 769}; 770 771static int __init initialize_ptr_random(void) 772{ 773 int key_size = sizeof(ptr_key); 774 int ret; 775 776 /* Use hw RNG if available. */ 777 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) { 778 static_branch_disable(¬_filled_random_ptr_key); 779 return 0; 780 } 781 782 ret = register_random_ready_notifier(&random_ready); 783 if (!ret) { 784 return 0; 785 } else if (ret == -EALREADY) { 786 /* This is in preemptible context */ 787 enable_ptr_key_workfn(&enable_ptr_key_work); 788 return 0; 789 } 790 791 return ret; 792} 793early_initcall(initialize_ptr_random); 794 795/* Maps a pointer to a 32 bit unique identifier. */ 796static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 797{ 798 unsigned long hashval; 799 800 if (static_branch_unlikely(¬_filled_random_ptr_key)) 801 return -EAGAIN; 802 803#ifdef CONFIG_64BIT 804 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 805 /* 806 * Mask off the first 32 bits, this makes explicit that we have 807 * modified the address (and 32 bits is plenty for a unique ID). 808 */ 809 hashval = hashval & 0xffffffff; 810#else 811 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 812#endif 813 *hashval_out = hashval; 814 return 0; 815} 816 817int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 818{ 819 return __ptr_to_hashval(ptr, hashval_out); 820} 821 822static char *ptr_to_id(char *buf, char *end, const void *ptr, 823 struct printf_spec spec) 824{ 825 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 826 unsigned long hashval; 827 int ret; 828 829 /* 830 * Print the real pointer value for NULL and error pointers, 831 * as they are not actual addresses. 832 */ 833 if (IS_ERR_OR_NULL(ptr)) 834 return pointer_string(buf, end, ptr, spec); 835 836 /* When debugging early boot use non-cryptographically secure hash. */ 837 if (unlikely(debug_boot_weak_hash)) { 838 hashval = hash_long((unsigned long)ptr, 32); 839 return pointer_string(buf, end, (const void *)hashval, spec); 840 } 841 842 ret = __ptr_to_hashval(ptr, &hashval); 843 if (ret) { 844 spec.field_width = 2 * sizeof(ptr); 845 /* string length must be less than default_width */ 846 return error_string(buf, end, str, spec); 847 } 848 849 return pointer_string(buf, end, (const void *)hashval, spec); 850} 851 852int kptr_restrict __read_mostly; 853 854static noinline_for_stack 855char *restricted_pointer(char *buf, char *end, const void *ptr, 856 struct printf_spec spec) 857{ 858 switch (kptr_restrict) { 859 case 0: 860 /* Handle as %p, hash and do _not_ leak addresses. */ 861 return ptr_to_id(buf, end, ptr, spec); 862 case 1: { 863 const struct cred *cred; 864 865 /* 866 * kptr_restrict==1 cannot be used in IRQ context 867 * because its test for CAP_SYSLOG would be meaningless. 868 */ 869 if (in_irq() || in_serving_softirq() || in_nmi()) { 870 if (spec.field_width == -1) 871 spec.field_width = 2 * sizeof(ptr); 872 return error_string(buf, end, "pK-error", spec); 873 } 874 875 /* 876 * Only print the real pointer value if the current 877 * process has CAP_SYSLOG and is running with the 878 * same credentials it started with. This is because 879 * access to files is checked at open() time, but %pK 880 * checks permission at read() time. We don't want to 881 * leak pointer values if a binary opens a file using 882 * %pK and then elevates privileges before reading it. 883 */ 884 cred = current_cred(); 885 if (!has_capability_noaudit(current, CAP_SYSLOG) || 886 !uid_eq(cred->euid, cred->uid) || 887 !gid_eq(cred->egid, cred->gid)) 888 ptr = NULL; 889 break; 890 } 891 case 2: 892 default: 893 /* Always print 0's for %pK */ 894 ptr = NULL; 895 break; 896 } 897 898 return pointer_string(buf, end, ptr, spec); 899} 900 901static noinline_for_stack 902char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 903 const char *fmt) 904{ 905 const char *array[4], *s; 906 const struct dentry *p; 907 int depth; 908 int i, n; 909 910 switch (fmt[1]) { 911 case '2': case '3': case '4': 912 depth = fmt[1] - '0'; 913 break; 914 default: 915 depth = 1; 916 } 917 918 rcu_read_lock(); 919 for (i = 0; i < depth; i++, d = p) { 920 if (check_pointer(&buf, end, d, spec)) { 921 rcu_read_unlock(); 922 return buf; 923 } 924 925 p = READ_ONCE(d->d_parent); 926 array[i] = READ_ONCE(d->d_name.name); 927 if (p == d) { 928 if (i) 929 array[i] = ""; 930 i++; 931 break; 932 } 933 } 934 s = array[--i]; 935 for (n = 0; n != spec.precision; n++, buf++) { 936 char c = *s++; 937 if (!c) { 938 if (!i) 939 break; 940 c = '/'; 941 s = array[--i]; 942 } 943 if (buf < end) 944 *buf = c; 945 } 946 rcu_read_unlock(); 947 return widen_string(buf, n, end, spec); 948} 949 950static noinline_for_stack 951char *file_dentry_name(char *buf, char *end, const struct file *f, 952 struct printf_spec spec, const char *fmt) 953{ 954 if (check_pointer(&buf, end, f, spec)) 955 return buf; 956 957 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 958} 959#ifdef CONFIG_BLOCK 960static noinline_for_stack 961char *bdev_name(char *buf, char *end, struct block_device *bdev, 962 struct printf_spec spec, const char *fmt) 963{ 964 struct gendisk *hd; 965 966 if (check_pointer(&buf, end, bdev, spec)) 967 return buf; 968 969 hd = bdev->bd_disk; 970 buf = string(buf, end, hd->disk_name, spec); 971 if (bdev->bd_partno) { 972 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 973 if (buf < end) 974 *buf = 'p'; 975 buf++; 976 } 977 buf = number(buf, end, bdev->bd_partno, spec); 978 } 979 return buf; 980} 981#endif 982 983static noinline_for_stack 984char *symbol_string(char *buf, char *end, void *ptr, 985 struct printf_spec spec, const char *fmt) 986{ 987 unsigned long value; 988#ifdef CONFIG_KALLSYMS 989 char sym[KSYM_SYMBOL_LEN]; 990#endif 991 992 if (fmt[1] == 'R') 993 ptr = __builtin_extract_return_addr(ptr); 994 value = (unsigned long)ptr; 995 996#ifdef CONFIG_KALLSYMS 997 if (*fmt == 'B') 998 sprint_backtrace(sym, value); 999 else if (*fmt != 's') 1000 sprint_symbol(sym, value); 1001 else 1002 sprint_symbol_no_offset(sym, value); 1003 1004 return string_nocheck(buf, end, sym, spec); 1005#else 1006 return special_hex_number(buf, end, value, sizeof(void *)); 1007#endif 1008} 1009 1010static const struct printf_spec default_str_spec = { 1011 .field_width = -1, 1012 .precision = -1, 1013}; 1014 1015static const struct printf_spec default_flag_spec = { 1016 .base = 16, 1017 .precision = -1, 1018 .flags = SPECIAL | SMALL, 1019}; 1020 1021static const struct printf_spec default_dec_spec = { 1022 .base = 10, 1023 .precision = -1, 1024}; 1025 1026static const struct printf_spec default_dec02_spec = { 1027 .base = 10, 1028 .field_width = 2, 1029 .precision = -1, 1030 .flags = ZEROPAD, 1031}; 1032 1033static const struct printf_spec default_dec04_spec = { 1034 .base = 10, 1035 .field_width = 4, 1036 .precision = -1, 1037 .flags = ZEROPAD, 1038}; 1039 1040static noinline_for_stack 1041char *resource_string(char *buf, char *end, struct resource *res, 1042 struct printf_spec spec, const char *fmt) 1043{ 1044#ifndef IO_RSRC_PRINTK_SIZE 1045#define IO_RSRC_PRINTK_SIZE 6 1046#endif 1047 1048#ifndef MEM_RSRC_PRINTK_SIZE 1049#define MEM_RSRC_PRINTK_SIZE 10 1050#endif 1051 static const struct printf_spec io_spec = { 1052 .base = 16, 1053 .field_width = IO_RSRC_PRINTK_SIZE, 1054 .precision = -1, 1055 .flags = SPECIAL | SMALL | ZEROPAD, 1056 }; 1057 static const struct printf_spec mem_spec = { 1058 .base = 16, 1059 .field_width = MEM_RSRC_PRINTK_SIZE, 1060 .precision = -1, 1061 .flags = SPECIAL | SMALL | ZEROPAD, 1062 }; 1063 static const struct printf_spec bus_spec = { 1064 .base = 16, 1065 .field_width = 2, 1066 .precision = -1, 1067 .flags = SMALL | ZEROPAD, 1068 }; 1069 static const struct printf_spec str_spec = { 1070 .field_width = -1, 1071 .precision = 10, 1072 .flags = LEFT, 1073 }; 1074 1075 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1076 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1077#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1078#define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1079#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1080#define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1081 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1082 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1083 1084 char *p = sym, *pend = sym + sizeof(sym); 1085 int decode = (fmt[0] == 'R') ? 1 : 0; 1086 const struct printf_spec *specp; 1087 1088 if (check_pointer(&buf, end, res, spec)) 1089 return buf; 1090 1091 *p++ = '['; 1092 if (res->flags & IORESOURCE_IO) { 1093 p = string_nocheck(p, pend, "io ", str_spec); 1094 specp = &io_spec; 1095 } else if (res->flags & IORESOURCE_MEM) { 1096 p = string_nocheck(p, pend, "mem ", str_spec); 1097 specp = &mem_spec; 1098 } else if (res->flags & IORESOURCE_IRQ) { 1099 p = string_nocheck(p, pend, "irq ", str_spec); 1100 specp = &default_dec_spec; 1101 } else if (res->flags & IORESOURCE_DMA) { 1102 p = string_nocheck(p, pend, "dma ", str_spec); 1103 specp = &default_dec_spec; 1104 } else if (res->flags & IORESOURCE_BUS) { 1105 p = string_nocheck(p, pend, "bus ", str_spec); 1106 specp = &bus_spec; 1107 } else { 1108 p = string_nocheck(p, pend, "??? ", str_spec); 1109 specp = &mem_spec; 1110 decode = 0; 1111 } 1112 if (decode && res->flags & IORESOURCE_UNSET) { 1113 p = string_nocheck(p, pend, "size ", str_spec); 1114 p = number(p, pend, resource_size(res), *specp); 1115 } else { 1116 p = number(p, pend, res->start, *specp); 1117 if (res->start != res->end) { 1118 *p++ = '-'; 1119 p = number(p, pend, res->end, *specp); 1120 } 1121 } 1122 if (decode) { 1123 if (res->flags & IORESOURCE_MEM_64) 1124 p = string_nocheck(p, pend, " 64bit", str_spec); 1125 if (res->flags & IORESOURCE_PREFETCH) 1126 p = string_nocheck(p, pend, " pref", str_spec); 1127 if (res->flags & IORESOURCE_WINDOW) 1128 p = string_nocheck(p, pend, " window", str_spec); 1129 if (res->flags & IORESOURCE_DISABLED) 1130 p = string_nocheck(p, pend, " disabled", str_spec); 1131 } else { 1132 p = string_nocheck(p, pend, " flags ", str_spec); 1133 p = number(p, pend, res->flags, default_flag_spec); 1134 } 1135 *p++ = ']'; 1136 *p = '\0'; 1137 1138 return string_nocheck(buf, end, sym, spec); 1139} 1140 1141static noinline_for_stack 1142char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1143 const char *fmt) 1144{ 1145 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1146 negative value, fallback to the default */ 1147 char separator; 1148 1149 if (spec.field_width == 0) 1150 /* nothing to print */ 1151 return buf; 1152 1153 if (check_pointer(&buf, end, addr, spec)) 1154 return buf; 1155 1156 switch (fmt[1]) { 1157 case 'C': 1158 separator = ':'; 1159 break; 1160 case 'D': 1161 separator = '-'; 1162 break; 1163 case 'N': 1164 separator = 0; 1165 break; 1166 default: 1167 separator = ' '; 1168 break; 1169 } 1170 1171 if (spec.field_width > 0) 1172 len = min_t(int, spec.field_width, 64); 1173 1174 for (i = 0; i < len; ++i) { 1175 if (buf < end) 1176 *buf = hex_asc_hi(addr[i]); 1177 ++buf; 1178 if (buf < end) 1179 *buf = hex_asc_lo(addr[i]); 1180 ++buf; 1181 1182 if (separator && i != len - 1) { 1183 if (buf < end) 1184 *buf = separator; 1185 ++buf; 1186 } 1187 } 1188 1189 return buf; 1190} 1191 1192static noinline_for_stack 1193char *bitmap_string(char *buf, char *end, unsigned long *bitmap, 1194 struct printf_spec spec, const char *fmt) 1195{ 1196 const int CHUNKSZ = 32; 1197 int nr_bits = max_t(int, spec.field_width, 0); 1198 int i, chunksz; 1199 bool first = true; 1200 1201 if (check_pointer(&buf, end, bitmap, spec)) 1202 return buf; 1203 1204 /* reused to print numbers */ 1205 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1206 1207 chunksz = nr_bits & (CHUNKSZ - 1); 1208 if (chunksz == 0) 1209 chunksz = CHUNKSZ; 1210 1211 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1212 for (; i >= 0; i -= CHUNKSZ) { 1213 u32 chunkmask, val; 1214 int word, bit; 1215 1216 chunkmask = ((1ULL << chunksz) - 1); 1217 word = i / BITS_PER_LONG; 1218 bit = i % BITS_PER_LONG; 1219 val = (bitmap[word] >> bit) & chunkmask; 1220 1221 if (!first) { 1222 if (buf < end) 1223 *buf = ','; 1224 buf++; 1225 } 1226 first = false; 1227 1228 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1229 buf = number(buf, end, val, spec); 1230 1231 chunksz = CHUNKSZ; 1232 } 1233 return buf; 1234} 1235 1236static noinline_for_stack 1237char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap, 1238 struct printf_spec spec, const char *fmt) 1239{ 1240 int nr_bits = max_t(int, spec.field_width, 0); 1241 /* current bit is 'cur', most recently seen range is [rbot, rtop] */ 1242 int cur, rbot, rtop; 1243 bool first = true; 1244 1245 if (check_pointer(&buf, end, bitmap, spec)) 1246 return buf; 1247 1248 rbot = cur = find_first_bit(bitmap, nr_bits); 1249 while (cur < nr_bits) { 1250 rtop = cur; 1251 cur = find_next_bit(bitmap, nr_bits, cur + 1); 1252 if (cur < nr_bits && cur <= rtop + 1) 1253 continue; 1254 1255 if (!first) { 1256 if (buf < end) 1257 *buf = ','; 1258 buf++; 1259 } 1260 first = false; 1261 1262 buf = number(buf, end, rbot, default_dec_spec); 1263 if (rbot < rtop) { 1264 if (buf < end) 1265 *buf = '-'; 1266 buf++; 1267 1268 buf = number(buf, end, rtop, default_dec_spec); 1269 } 1270 1271 rbot = cur; 1272 } 1273 return buf; 1274} 1275 1276static noinline_for_stack 1277char *mac_address_string(char *buf, char *end, u8 *addr, 1278 struct printf_spec spec, const char *fmt) 1279{ 1280 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1281 char *p = mac_addr; 1282 int i; 1283 char separator; 1284 bool reversed = false; 1285 1286 if (check_pointer(&buf, end, addr, spec)) 1287 return buf; 1288 1289 switch (fmt[1]) { 1290 case 'F': 1291 separator = '-'; 1292 break; 1293 1294 case 'R': 1295 reversed = true; 1296 /* fall through */ 1297 1298 default: 1299 separator = ':'; 1300 break; 1301 } 1302 1303 for (i = 0; i < 6; i++) { 1304 if (reversed) 1305 p = hex_byte_pack(p, addr[5 - i]); 1306 else 1307 p = hex_byte_pack(p, addr[i]); 1308 1309 if (fmt[0] == 'M' && i != 5) 1310 *p++ = separator; 1311 } 1312 *p = '\0'; 1313 1314 return string_nocheck(buf, end, mac_addr, spec); 1315} 1316 1317static noinline_for_stack 1318char *ip4_string(char *p, const u8 *addr, const char *fmt) 1319{ 1320 int i; 1321 bool leading_zeros = (fmt[0] == 'i'); 1322 int index; 1323 int step; 1324 1325 switch (fmt[2]) { 1326 case 'h': 1327#ifdef __BIG_ENDIAN 1328 index = 0; 1329 step = 1; 1330#else 1331 index = 3; 1332 step = -1; 1333#endif 1334 break; 1335 case 'l': 1336 index = 3; 1337 step = -1; 1338 break; 1339 case 'n': 1340 case 'b': 1341 default: 1342 index = 0; 1343 step = 1; 1344 break; 1345 } 1346 for (i = 0; i < 4; i++) { 1347 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1348 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1349 if (leading_zeros) { 1350 if (digits < 3) 1351 *p++ = '0'; 1352 if (digits < 2) 1353 *p++ = '0'; 1354 } 1355 /* reverse the digits in the quad */ 1356 while (digits--) 1357 *p++ = temp[digits]; 1358 if (i < 3) 1359 *p++ = '.'; 1360 index += step; 1361 } 1362 *p = '\0'; 1363 1364 return p; 1365} 1366 1367static noinline_for_stack 1368char *ip6_compressed_string(char *p, const char *addr) 1369{ 1370 int i, j, range; 1371 unsigned char zerolength[8]; 1372 int longest = 1; 1373 int colonpos = -1; 1374 u16 word; 1375 u8 hi, lo; 1376 bool needcolon = false; 1377 bool useIPv4; 1378 struct in6_addr in6; 1379 1380 memcpy(&in6, addr, sizeof(struct in6_addr)); 1381 1382 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1383 1384 memset(zerolength, 0, sizeof(zerolength)); 1385 1386 if (useIPv4) 1387 range = 6; 1388 else 1389 range = 8; 1390 1391 /* find position of longest 0 run */ 1392 for (i = 0; i < range; i++) { 1393 for (j = i; j < range; j++) { 1394 if (in6.s6_addr16[j] != 0) 1395 break; 1396 zerolength[i]++; 1397 } 1398 } 1399 for (i = 0; i < range; i++) { 1400 if (zerolength[i] > longest) { 1401 longest = zerolength[i]; 1402 colonpos = i; 1403 } 1404 } 1405 if (longest == 1) /* don't compress a single 0 */ 1406 colonpos = -1; 1407 1408 /* emit address */ 1409 for (i = 0; i < range; i++) { 1410 if (i == colonpos) { 1411 if (needcolon || i == 0) 1412 *p++ = ':'; 1413 *p++ = ':'; 1414 needcolon = false; 1415 i += longest - 1; 1416 continue; 1417 } 1418 if (needcolon) { 1419 *p++ = ':'; 1420 needcolon = false; 1421 } 1422 /* hex u16 without leading 0s */ 1423 word = ntohs(in6.s6_addr16[i]); 1424 hi = word >> 8; 1425 lo = word & 0xff; 1426 if (hi) { 1427 if (hi > 0x0f) 1428 p = hex_byte_pack(p, hi); 1429 else 1430 *p++ = hex_asc_lo(hi); 1431 p = hex_byte_pack(p, lo); 1432 } 1433 else if (lo > 0x0f) 1434 p = hex_byte_pack(p, lo); 1435 else 1436 *p++ = hex_asc_lo(lo); 1437 needcolon = true; 1438 } 1439 1440 if (useIPv4) { 1441 if (needcolon) 1442 *p++ = ':'; 1443 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1444 } 1445 *p = '\0'; 1446 1447 return p; 1448} 1449 1450static noinline_for_stack 1451char *ip6_string(char *p, const char *addr, const char *fmt) 1452{ 1453 int i; 1454 1455 for (i = 0; i < 8; i++) { 1456 p = hex_byte_pack(p, *addr++); 1457 p = hex_byte_pack(p, *addr++); 1458 if (fmt[0] == 'I' && i != 7) 1459 *p++ = ':'; 1460 } 1461 *p = '\0'; 1462 1463 return p; 1464} 1465 1466static noinline_for_stack 1467char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1468 struct printf_spec spec, const char *fmt) 1469{ 1470 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1471 1472 if (fmt[0] == 'I' && fmt[2] == 'c') 1473 ip6_compressed_string(ip6_addr, addr); 1474 else 1475 ip6_string(ip6_addr, addr, fmt); 1476 1477 return string_nocheck(buf, end, ip6_addr, spec); 1478} 1479 1480static noinline_for_stack 1481char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1482 struct printf_spec spec, const char *fmt) 1483{ 1484 char ip4_addr[sizeof("255.255.255.255")]; 1485 1486 ip4_string(ip4_addr, addr, fmt); 1487 1488 return string_nocheck(buf, end, ip4_addr, spec); 1489} 1490 1491static noinline_for_stack 1492char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1493 struct printf_spec spec, const char *fmt) 1494{ 1495 bool have_p = false, have_s = false, have_f = false, have_c = false; 1496 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1497 sizeof(":12345") + sizeof("/123456789") + 1498 sizeof("%1234567890")]; 1499 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1500 const u8 *addr = (const u8 *) &sa->sin6_addr; 1501 char fmt6[2] = { fmt[0], '6' }; 1502 u8 off = 0; 1503 1504 fmt++; 1505 while (isalpha(*++fmt)) { 1506 switch (*fmt) { 1507 case 'p': 1508 have_p = true; 1509 break; 1510 case 'f': 1511 have_f = true; 1512 break; 1513 case 's': 1514 have_s = true; 1515 break; 1516 case 'c': 1517 have_c = true; 1518 break; 1519 } 1520 } 1521 1522 if (have_p || have_s || have_f) { 1523 *p = '['; 1524 off = 1; 1525 } 1526 1527 if (fmt6[0] == 'I' && have_c) 1528 p = ip6_compressed_string(ip6_addr + off, addr); 1529 else 1530 p = ip6_string(ip6_addr + off, addr, fmt6); 1531 1532 if (have_p || have_s || have_f) 1533 *p++ = ']'; 1534 1535 if (have_p) { 1536 *p++ = ':'; 1537 p = number(p, pend, ntohs(sa->sin6_port), spec); 1538 } 1539 if (have_f) { 1540 *p++ = '/'; 1541 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1542 IPV6_FLOWINFO_MASK), spec); 1543 } 1544 if (have_s) { 1545 *p++ = '%'; 1546 p = number(p, pend, sa->sin6_scope_id, spec); 1547 } 1548 *p = '\0'; 1549 1550 return string_nocheck(buf, end, ip6_addr, spec); 1551} 1552 1553static noinline_for_stack 1554char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1555 struct printf_spec spec, const char *fmt) 1556{ 1557 bool have_p = false; 1558 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1559 char *pend = ip4_addr + sizeof(ip4_addr); 1560 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1561 char fmt4[3] = { fmt[0], '4', 0 }; 1562 1563 fmt++; 1564 while (isalpha(*++fmt)) { 1565 switch (*fmt) { 1566 case 'p': 1567 have_p = true; 1568 break; 1569 case 'h': 1570 case 'l': 1571 case 'n': 1572 case 'b': 1573 fmt4[2] = *fmt; 1574 break; 1575 } 1576 } 1577 1578 p = ip4_string(ip4_addr, addr, fmt4); 1579 if (have_p) { 1580 *p++ = ':'; 1581 p = number(p, pend, ntohs(sa->sin_port), spec); 1582 } 1583 *p = '\0'; 1584 1585 return string_nocheck(buf, end, ip4_addr, spec); 1586} 1587 1588static noinline_for_stack 1589char *ip_addr_string(char *buf, char *end, const void *ptr, 1590 struct printf_spec spec, const char *fmt) 1591{ 1592 char *err_fmt_msg; 1593 1594 if (check_pointer(&buf, end, ptr, spec)) 1595 return buf; 1596 1597 switch (fmt[1]) { 1598 case '6': 1599 return ip6_addr_string(buf, end, ptr, spec, fmt); 1600 case '4': 1601 return ip4_addr_string(buf, end, ptr, spec, fmt); 1602 case 'S': { 1603 const union { 1604 struct sockaddr raw; 1605 struct sockaddr_in v4; 1606 struct sockaddr_in6 v6; 1607 } *sa = ptr; 1608 1609 switch (sa->raw.sa_family) { 1610 case AF_INET: 1611 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1612 case AF_INET6: 1613 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1614 default: 1615 return error_string(buf, end, "(einval)", spec); 1616 }} 1617 } 1618 1619 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1620 return error_string(buf, end, err_fmt_msg, spec); 1621} 1622 1623static noinline_for_stack 1624char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1625 const char *fmt) 1626{ 1627 bool found = true; 1628 int count = 1; 1629 unsigned int flags = 0; 1630 int len; 1631 1632 if (spec.field_width == 0) 1633 return buf; /* nothing to print */ 1634 1635 if (check_pointer(&buf, end, addr, spec)) 1636 return buf; 1637 1638 do { 1639 switch (fmt[count++]) { 1640 case 'a': 1641 flags |= ESCAPE_ANY; 1642 break; 1643 case 'c': 1644 flags |= ESCAPE_SPECIAL; 1645 break; 1646 case 'h': 1647 flags |= ESCAPE_HEX; 1648 break; 1649 case 'n': 1650 flags |= ESCAPE_NULL; 1651 break; 1652 case 'o': 1653 flags |= ESCAPE_OCTAL; 1654 break; 1655 case 'p': 1656 flags |= ESCAPE_NP; 1657 break; 1658 case 's': 1659 flags |= ESCAPE_SPACE; 1660 break; 1661 default: 1662 found = false; 1663 break; 1664 } 1665 } while (found); 1666 1667 if (!flags) 1668 flags = ESCAPE_ANY_NP; 1669 1670 len = spec.field_width < 0 ? 1 : spec.field_width; 1671 1672 /* 1673 * string_escape_mem() writes as many characters as it can to 1674 * the given buffer, and returns the total size of the output 1675 * had the buffer been big enough. 1676 */ 1677 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1678 1679 return buf; 1680} 1681 1682static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1683 struct printf_spec spec, const char *fmt) 1684{ 1685 va_list va; 1686 1687 if (check_pointer(&buf, end, va_fmt, spec)) 1688 return buf; 1689 1690 va_copy(va, *va_fmt->va); 1691 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1692 va_end(va); 1693 1694 return buf; 1695} 1696 1697static noinline_for_stack 1698char *uuid_string(char *buf, char *end, const u8 *addr, 1699 struct printf_spec spec, const char *fmt) 1700{ 1701 char uuid[UUID_STRING_LEN + 1]; 1702 char *p = uuid; 1703 int i; 1704 const u8 *index = uuid_index; 1705 bool uc = false; 1706 1707 if (check_pointer(&buf, end, addr, spec)) 1708 return buf; 1709 1710 switch (*(++fmt)) { 1711 case 'L': 1712 uc = true; 1713 /* fall through */ 1714 case 'l': 1715 index = guid_index; 1716 break; 1717 case 'B': 1718 uc = true; 1719 break; 1720 } 1721 1722 for (i = 0; i < 16; i++) { 1723 if (uc) 1724 p = hex_byte_pack_upper(p, addr[index[i]]); 1725 else 1726 p = hex_byte_pack(p, addr[index[i]]); 1727 switch (i) { 1728 case 3: 1729 case 5: 1730 case 7: 1731 case 9: 1732 *p++ = '-'; 1733 break; 1734 } 1735 } 1736 1737 *p = 0; 1738 1739 return string_nocheck(buf, end, uuid, spec); 1740} 1741 1742static noinline_for_stack 1743char *netdev_bits(char *buf, char *end, const void *addr, 1744 struct printf_spec spec, const char *fmt) 1745{ 1746 unsigned long long num; 1747 int size; 1748 1749 if (check_pointer(&buf, end, addr, spec)) 1750 return buf; 1751 1752 switch (fmt[1]) { 1753 case 'F': 1754 num = *(const netdev_features_t *)addr; 1755 size = sizeof(netdev_features_t); 1756 break; 1757 default: 1758 return error_string(buf, end, "(%pN?)", spec); 1759 } 1760 1761 return special_hex_number(buf, end, num, size); 1762} 1763 1764static noinline_for_stack 1765char *address_val(char *buf, char *end, const void *addr, 1766 struct printf_spec spec, const char *fmt) 1767{ 1768 unsigned long long num; 1769 int size; 1770 1771 if (check_pointer(&buf, end, addr, spec)) 1772 return buf; 1773 1774 switch (fmt[1]) { 1775 case 'd': 1776 num = *(const dma_addr_t *)addr; 1777 size = sizeof(dma_addr_t); 1778 break; 1779 case 'p': 1780 default: 1781 num = *(const phys_addr_t *)addr; 1782 size = sizeof(phys_addr_t); 1783 break; 1784 } 1785 1786 return special_hex_number(buf, end, num, size); 1787} 1788 1789static noinline_for_stack 1790char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1791{ 1792 int year = tm->tm_year + (r ? 0 : 1900); 1793 int mon = tm->tm_mon + (r ? 0 : 1); 1794 1795 buf = number(buf, end, year, default_dec04_spec); 1796 if (buf < end) 1797 *buf = '-'; 1798 buf++; 1799 1800 buf = number(buf, end, mon, default_dec02_spec); 1801 if (buf < end) 1802 *buf = '-'; 1803 buf++; 1804 1805 return number(buf, end, tm->tm_mday, default_dec02_spec); 1806} 1807 1808static noinline_for_stack 1809char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1810{ 1811 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1812 if (buf < end) 1813 *buf = ':'; 1814 buf++; 1815 1816 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1817 if (buf < end) 1818 *buf = ':'; 1819 buf++; 1820 1821 return number(buf, end, tm->tm_sec, default_dec02_spec); 1822} 1823 1824static noinline_for_stack 1825char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1826 struct printf_spec spec, const char *fmt) 1827{ 1828 bool have_t = true, have_d = true; 1829 bool raw = false; 1830 int count = 2; 1831 1832 if (check_pointer(&buf, end, tm, spec)) 1833 return buf; 1834 1835 switch (fmt[count]) { 1836 case 'd': 1837 have_t = false; 1838 count++; 1839 break; 1840 case 't': 1841 have_d = false; 1842 count++; 1843 break; 1844 } 1845 1846 raw = fmt[count] == 'r'; 1847 1848 if (have_d) 1849 buf = date_str(buf, end, tm, raw); 1850 if (have_d && have_t) { 1851 /* Respect ISO 8601 */ 1852 if (buf < end) 1853 *buf = 'T'; 1854 buf++; 1855 } 1856 if (have_t) 1857 buf = time_str(buf, end, tm, raw); 1858 1859 return buf; 1860} 1861 1862static noinline_for_stack 1863char *time64_str(char *buf, char *end, const time64_t time, 1864 struct printf_spec spec, const char *fmt) 1865{ 1866 struct rtc_time rtc_time; 1867 struct tm tm; 1868 1869 time64_to_tm(time, 0, &tm); 1870 1871 rtc_time.tm_sec = tm.tm_sec; 1872 rtc_time.tm_min = tm.tm_min; 1873 rtc_time.tm_hour = tm.tm_hour; 1874 rtc_time.tm_mday = tm.tm_mday; 1875 rtc_time.tm_mon = tm.tm_mon; 1876 rtc_time.tm_year = tm.tm_year; 1877 rtc_time.tm_wday = tm.tm_wday; 1878 rtc_time.tm_yday = tm.tm_yday; 1879 1880 rtc_time.tm_isdst = 0; 1881 1882 return rtc_str(buf, end, &rtc_time, spec, fmt); 1883} 1884 1885static noinline_for_stack 1886char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1887 const char *fmt) 1888{ 1889 switch (fmt[1]) { 1890 case 'R': 1891 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1892 case 'T': 1893 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 1894 default: 1895 return error_string(buf, end, "(%pt?)", spec); 1896 } 1897} 1898 1899static noinline_for_stack 1900char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1901 const char *fmt) 1902{ 1903 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1904 return error_string(buf, end, "(%pC?)", spec); 1905 1906 if (check_pointer(&buf, end, clk, spec)) 1907 return buf; 1908 1909 switch (fmt[1]) { 1910 case 'n': 1911 default: 1912#ifdef CONFIG_COMMON_CLK 1913 return string(buf, end, __clk_get_name(clk), spec); 1914#else 1915 return ptr_to_id(buf, end, clk, spec); 1916#endif 1917 } 1918} 1919 1920static 1921char *format_flags(char *buf, char *end, unsigned long flags, 1922 const struct trace_print_flags *names) 1923{ 1924 unsigned long mask; 1925 1926 for ( ; flags && names->name; names++) { 1927 mask = names->mask; 1928 if ((flags & mask) != mask) 1929 continue; 1930 1931 buf = string(buf, end, names->name, default_str_spec); 1932 1933 flags &= ~mask; 1934 if (flags) { 1935 if (buf < end) 1936 *buf = '|'; 1937 buf++; 1938 } 1939 } 1940 1941 if (flags) 1942 buf = number(buf, end, flags, default_flag_spec); 1943 1944 return buf; 1945} 1946 1947static noinline_for_stack 1948char *flags_string(char *buf, char *end, void *flags_ptr, 1949 struct printf_spec spec, const char *fmt) 1950{ 1951 unsigned long flags; 1952 const struct trace_print_flags *names; 1953 1954 if (check_pointer(&buf, end, flags_ptr, spec)) 1955 return buf; 1956 1957 switch (fmt[1]) { 1958 case 'p': 1959 flags = *(unsigned long *)flags_ptr; 1960 /* Remove zone id */ 1961 flags &= (1UL << NR_PAGEFLAGS) - 1; 1962 names = pageflag_names; 1963 break; 1964 case 'v': 1965 flags = *(unsigned long *)flags_ptr; 1966 names = vmaflag_names; 1967 break; 1968 case 'g': 1969 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 1970 names = gfpflag_names; 1971 break; 1972 default: 1973 return error_string(buf, end, "(%pG?)", spec); 1974 } 1975 1976 return format_flags(buf, end, flags, names); 1977} 1978 1979static noinline_for_stack 1980char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 1981 char *end) 1982{ 1983 int depth; 1984 1985 /* Loop starting from the root node to the current node. */ 1986 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 1987 /* 1988 * Only get a reference for other nodes (i.e. parent nodes). 1989 * fwnode refcount may be 0 here. 1990 */ 1991 struct fwnode_handle *__fwnode = depth ? 1992 fwnode_get_nth_parent(fwnode, depth) : fwnode; 1993 1994 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 1995 default_str_spec); 1996 buf = string(buf, end, fwnode_get_name(__fwnode), 1997 default_str_spec); 1998 1999 if (depth) 2000 fwnode_handle_put(__fwnode); 2001 } 2002 2003 return buf; 2004} 2005 2006static noinline_for_stack 2007char *device_node_string(char *buf, char *end, struct device_node *dn, 2008 struct printf_spec spec, const char *fmt) 2009{ 2010 char tbuf[sizeof("xxxx") + 1]; 2011 const char *p; 2012 int ret; 2013 char *buf_start = buf; 2014 struct property *prop; 2015 bool has_mult, pass; 2016 2017 struct printf_spec str_spec = spec; 2018 str_spec.field_width = -1; 2019 2020 if (fmt[0] != 'F') 2021 return error_string(buf, end, "(%pO?)", spec); 2022 2023 if (!IS_ENABLED(CONFIG_OF)) 2024 return error_string(buf, end, "(%pOF?)", spec); 2025 2026 if (check_pointer(&buf, end, dn, spec)) 2027 return buf; 2028 2029 /* simple case without anything any more format specifiers */ 2030 fmt++; 2031 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2032 fmt = "f"; 2033 2034 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2035 int precision; 2036 if (pass) { 2037 if (buf < end) 2038 *buf = ':'; 2039 buf++; 2040 } 2041 2042 switch (*fmt) { 2043 case 'f': /* full_name */ 2044 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2045 end); 2046 break; 2047 case 'n': /* name */ 2048 p = fwnode_get_name(of_fwnode_handle(dn)); 2049 precision = str_spec.precision; 2050 str_spec.precision = strchrnul(p, '@') - p; 2051 buf = string(buf, end, p, str_spec); 2052 str_spec.precision = precision; 2053 break; 2054 case 'p': /* phandle */ 2055 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2056 break; 2057 case 'P': /* path-spec */ 2058 p = fwnode_get_name(of_fwnode_handle(dn)); 2059 if (!p[1]) 2060 p = "/"; 2061 buf = string(buf, end, p, str_spec); 2062 break; 2063 case 'F': /* flags */ 2064 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2065 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2066 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2067 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2068 tbuf[4] = 0; 2069 buf = string_nocheck(buf, end, tbuf, str_spec); 2070 break; 2071 case 'c': /* major compatible string */ 2072 ret = of_property_read_string(dn, "compatible", &p); 2073 if (!ret) 2074 buf = string(buf, end, p, str_spec); 2075 break; 2076 case 'C': /* full compatible string */ 2077 has_mult = false; 2078 of_property_for_each_string(dn, "compatible", prop, p) { 2079 if (has_mult) 2080 buf = string_nocheck(buf, end, ",", str_spec); 2081 buf = string_nocheck(buf, end, "\"", str_spec); 2082 buf = string(buf, end, p, str_spec); 2083 buf = string_nocheck(buf, end, "\"", str_spec); 2084 2085 has_mult = true; 2086 } 2087 break; 2088 default: 2089 break; 2090 } 2091 } 2092 2093 return widen_string(buf, buf - buf_start, end, spec); 2094} 2095 2096static noinline_for_stack 2097char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2098 struct printf_spec spec, const char *fmt) 2099{ 2100 struct printf_spec str_spec = spec; 2101 char *buf_start = buf; 2102 2103 str_spec.field_width = -1; 2104 2105 if (*fmt != 'w') 2106 return error_string(buf, end, "(%pf?)", spec); 2107 2108 if (check_pointer(&buf, end, fwnode, spec)) 2109 return buf; 2110 2111 fmt++; 2112 2113 switch (*fmt) { 2114 case 'P': /* name */ 2115 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2116 break; 2117 case 'f': /* full_name */ 2118 default: 2119 buf = fwnode_full_name_string(fwnode, buf, end); 2120 break; 2121 } 2122 2123 return widen_string(buf, buf - buf_start, end, spec); 2124} 2125 2126/* 2127 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2128 * by an extra set of alphanumeric characters that are extended format 2129 * specifiers. 2130 * 2131 * Please update scripts/checkpatch.pl when adding/removing conversion 2132 * characters. (Search for "check for vsprintf extension"). 2133 * 2134 * Right now we handle: 2135 * 2136 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2137 * - 's' For symbolic direct pointers (or function descriptors) without offset 2138 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2139 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2140 * %ps and %pS. Be careful when re-using these specifiers. 2141 * - 'B' For backtraced symbolic direct pointers with offset 2142 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2143 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2144 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2145 * width which must be explicitly specified either as part of the 2146 * format string '%32b[l]' or through '%*b[l]', [l] selects 2147 * range-list format instead of hex format 2148 * - 'M' For a 6-byte MAC address, it prints the address in the 2149 * usual colon-separated hex notation 2150 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2151 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2152 * with a dash-separated hex notation 2153 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2154 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2155 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2156 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2157 * [S][pfs] 2158 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2159 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2160 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2161 * IPv6 omits the colons (01020304...0f) 2162 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2163 * [S][pfs] 2164 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2165 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2166 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2167 * - 'I[6S]c' for IPv6 addresses printed as specified by 2168 * https://tools.ietf.org/html/rfc5952 2169 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2170 * of the following flags (see string_escape_mem() for the 2171 * details): 2172 * a - ESCAPE_ANY 2173 * c - ESCAPE_SPECIAL 2174 * h - ESCAPE_HEX 2175 * n - ESCAPE_NULL 2176 * o - ESCAPE_OCTAL 2177 * p - ESCAPE_NP 2178 * s - ESCAPE_SPACE 2179 * By default ESCAPE_ANY_NP is used. 2180 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2181 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2182 * Options for %pU are: 2183 * b big endian lower case hex (default) 2184 * B big endian UPPER case hex 2185 * l little endian lower case hex 2186 * L little endian UPPER case hex 2187 * big endian output byte order is: 2188 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2189 * little endian output byte order is: 2190 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2191 * - 'V' For a struct va_format which contains a format string * and va_list *, 2192 * call vsnprintf(->format, *->va_list). 2193 * Implements a "recursive vsnprintf". 2194 * Do not use this feature without some mechanism to verify the 2195 * correctness of the format string and va_list arguments. 2196 * - 'K' For a kernel pointer that should be hidden from unprivileged users 2197 * - 'NF' For a netdev_features_t 2198 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2199 * a certain separator (' ' by default): 2200 * C colon 2201 * D dash 2202 * N no separator 2203 * The maximum supported length is 64 bytes of the input. Consider 2204 * to use print_hex_dump() for the larger input. 2205 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2206 * (default assumed to be phys_addr_t, passed by reference) 2207 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2208 * - 'D[234]' Same as 'd' but for a struct file 2209 * - 'g' For block_device name (gendisk + partition number) 2210 * - 't[RT][dt][r]' For time and date as represented by: 2211 * R struct rtc_time 2212 * T time64_t 2213 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2214 * (legacy clock framework) of the clock 2215 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2216 * (legacy clock framework) of the clock 2217 * - 'G' For flags to be printed as a collection of symbolic strings that would 2218 * construct the specific value. Supported flags given by option: 2219 * p page flags (see struct page) given as pointer to unsigned long 2220 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2221 * v vma flags (VM_*) given as pointer to unsigned long 2222 * - 'OF[fnpPcCF]' For a device tree object 2223 * Without any optional arguments prints the full_name 2224 * f device node full_name 2225 * n device node name 2226 * p device node phandle 2227 * P device node path spec (name + @unit) 2228 * F device node flags 2229 * c major compatible string 2230 * C full compatible string 2231 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2232 * Without an option prints the full name of the node 2233 * f full name 2234 * P node name, including a possible unit address 2235 * - 'x' For printing the address. Equivalent to "%lx". 2236 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2237 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2238 * or user (u) memory to probe, and: 2239 * s a string, equivalent to "%s" on direct vsnprintf() use 2240 * 2241 * ** When making changes please also update: 2242 * Documentation/core-api/printk-formats.rst 2243 * 2244 * Note: The default behaviour (unadorned %p) is to hash the address, 2245 * rendering it useful as a unique identifier. 2246 */ 2247static noinline_for_stack 2248char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2249 struct printf_spec spec) 2250{ 2251 switch (*fmt) { 2252 case 'S': 2253 case 's': 2254 ptr = dereference_symbol_descriptor(ptr); 2255 /* fall through */ 2256 case 'B': 2257 return symbol_string(buf, end, ptr, spec, fmt); 2258 case 'R': 2259 case 'r': 2260 return resource_string(buf, end, ptr, spec, fmt); 2261 case 'h': 2262 return hex_string(buf, end, ptr, spec, fmt); 2263 case 'b': 2264 switch (fmt[1]) { 2265 case 'l': 2266 return bitmap_list_string(buf, end, ptr, spec, fmt); 2267 default: 2268 return bitmap_string(buf, end, ptr, spec, fmt); 2269 } 2270 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2271 case 'm': /* Contiguous: 000102030405 */ 2272 /* [mM]F (FDDI) */ 2273 /* [mM]R (Reverse order; Bluetooth) */ 2274 return mac_address_string(buf, end, ptr, spec, fmt); 2275 case 'I': /* Formatted IP supported 2276 * 4: 1.2.3.4 2277 * 6: 0001:0203:...:0708 2278 * 6c: 1::708 or 1::1.2.3.4 2279 */ 2280 case 'i': /* Contiguous: 2281 * 4: 001.002.003.004 2282 * 6: 000102...0f 2283 */ 2284 return ip_addr_string(buf, end, ptr, spec, fmt); 2285 case 'E': 2286 return escaped_string(buf, end, ptr, spec, fmt); 2287 case 'U': 2288 return uuid_string(buf, end, ptr, spec, fmt); 2289 case 'V': 2290 return va_format(buf, end, ptr, spec, fmt); 2291 case 'K': 2292 return restricted_pointer(buf, end, ptr, spec); 2293 case 'N': 2294 return netdev_bits(buf, end, ptr, spec, fmt); 2295 case 'a': 2296 return address_val(buf, end, ptr, spec, fmt); 2297 case 'd': 2298 return dentry_name(buf, end, ptr, spec, fmt); 2299 case 't': 2300 return time_and_date(buf, end, ptr, spec, fmt); 2301 case 'C': 2302 return clock(buf, end, ptr, spec, fmt); 2303 case 'D': 2304 return file_dentry_name(buf, end, ptr, spec, fmt); 2305#ifdef CONFIG_BLOCK 2306 case 'g': 2307 return bdev_name(buf, end, ptr, spec, fmt); 2308#endif 2309 2310 case 'G': 2311 return flags_string(buf, end, ptr, spec, fmt); 2312 case 'O': 2313 return device_node_string(buf, end, ptr, spec, fmt + 1); 2314 case 'f': 2315 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2316 case 'x': 2317 return pointer_string(buf, end, ptr, spec); 2318 case 'e': 2319 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2320 if (!IS_ERR(ptr)) 2321 break; 2322 return err_ptr(buf, end, ptr, spec); 2323 case 'u': 2324 case 'k': 2325 switch (fmt[1]) { 2326 case 's': 2327 return string(buf, end, ptr, spec); 2328 default: 2329 return error_string(buf, end, "(einval)", spec); 2330 } 2331 } 2332 2333 /* default is to _not_ leak addresses, hash before printing */ 2334 return ptr_to_id(buf, end, ptr, spec); 2335} 2336 2337/* 2338 * Helper function to decode printf style format. 2339 * Each call decode a token from the format and return the 2340 * number of characters read (or likely the delta where it wants 2341 * to go on the next call). 2342 * The decoded token is returned through the parameters 2343 * 2344 * 'h', 'l', or 'L' for integer fields 2345 * 'z' support added 23/7/1999 S.H. 2346 * 'z' changed to 'Z' --davidm 1/25/99 2347 * 'Z' changed to 'z' --adobriyan 2017-01-25 2348 * 't' added for ptrdiff_t 2349 * 2350 * @fmt: the format string 2351 * @type of the token returned 2352 * @flags: various flags such as +, -, # tokens.. 2353 * @field_width: overwritten width 2354 * @base: base of the number (octal, hex, ...) 2355 * @precision: precision of a number 2356 * @qualifier: qualifier of a number (long, size_t, ...) 2357 */ 2358static noinline_for_stack 2359int format_decode(const char *fmt, struct printf_spec *spec) 2360{ 2361 const char *start = fmt; 2362 char qualifier; 2363 2364 /* we finished early by reading the field width */ 2365 if (spec->type == FORMAT_TYPE_WIDTH) { 2366 if (spec->field_width < 0) { 2367 spec->field_width = -spec->field_width; 2368 spec->flags |= LEFT; 2369 } 2370 spec->type = FORMAT_TYPE_NONE; 2371 goto precision; 2372 } 2373 2374 /* we finished early by reading the precision */ 2375 if (spec->type == FORMAT_TYPE_PRECISION) { 2376 if (spec->precision < 0) 2377 spec->precision = 0; 2378 2379 spec->type = FORMAT_TYPE_NONE; 2380 goto qualifier; 2381 } 2382 2383 /* By default */ 2384 spec->type = FORMAT_TYPE_NONE; 2385 2386 for (; *fmt ; ++fmt) { 2387 if (*fmt == '%') 2388 break; 2389 } 2390 2391 /* Return the current non-format string */ 2392 if (fmt != start || !*fmt) 2393 return fmt - start; 2394 2395 /* Process flags */ 2396 spec->flags = 0; 2397 2398 while (1) { /* this also skips first '%' */ 2399 bool found = true; 2400 2401 ++fmt; 2402 2403 switch (*fmt) { 2404 case '-': spec->flags |= LEFT; break; 2405 case '+': spec->flags |= PLUS; break; 2406 case ' ': spec->flags |= SPACE; break; 2407 case '#': spec->flags |= SPECIAL; break; 2408 case '0': spec->flags |= ZEROPAD; break; 2409 default: found = false; 2410 } 2411 2412 if (!found) 2413 break; 2414 } 2415 2416 /* get field width */ 2417 spec->field_width = -1; 2418 2419 if (isdigit(*fmt)) 2420 spec->field_width = skip_atoi(&fmt); 2421 else if (*fmt == '*') { 2422 /* it's the next argument */ 2423 spec->type = FORMAT_TYPE_WIDTH; 2424 return ++fmt - start; 2425 } 2426 2427precision: 2428 /* get the precision */ 2429 spec->precision = -1; 2430 if (*fmt == '.') { 2431 ++fmt; 2432 if (isdigit(*fmt)) { 2433 spec->precision = skip_atoi(&fmt); 2434 if (spec->precision < 0) 2435 spec->precision = 0; 2436 } else if (*fmt == '*') { 2437 /* it's the next argument */ 2438 spec->type = FORMAT_TYPE_PRECISION; 2439 return ++fmt - start; 2440 } 2441 } 2442 2443qualifier: 2444 /* get the conversion qualifier */ 2445 qualifier = 0; 2446 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2447 *fmt == 'z' || *fmt == 't') { 2448 qualifier = *fmt++; 2449 if (unlikely(qualifier == *fmt)) { 2450 if (qualifier == 'l') { 2451 qualifier = 'L'; 2452 ++fmt; 2453 } else if (qualifier == 'h') { 2454 qualifier = 'H'; 2455 ++fmt; 2456 } 2457 } 2458 } 2459 2460 /* default base */ 2461 spec->base = 10; 2462 switch (*fmt) { 2463 case 'c': 2464 spec->type = FORMAT_TYPE_CHAR; 2465 return ++fmt - start; 2466 2467 case 's': 2468 spec->type = FORMAT_TYPE_STR; 2469 return ++fmt - start; 2470 2471 case 'p': 2472 spec->type = FORMAT_TYPE_PTR; 2473 return ++fmt - start; 2474 2475 case '%': 2476 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2477 return ++fmt - start; 2478 2479 /* integer number formats - set up the flags and "break" */ 2480 case 'o': 2481 spec->base = 8; 2482 break; 2483 2484 case 'x': 2485 spec->flags |= SMALL; 2486 /* fall through */ 2487 2488 case 'X': 2489 spec->base = 16; 2490 break; 2491 2492 case 'd': 2493 case 'i': 2494 spec->flags |= SIGN; 2495 case 'u': 2496 break; 2497 2498 case 'n': 2499 /* 2500 * Since %n poses a greater security risk than 2501 * utility, treat it as any other invalid or 2502 * unsupported format specifier. 2503 */ 2504 /* fall through */ 2505 2506 default: 2507 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2508 spec->type = FORMAT_TYPE_INVALID; 2509 return fmt - start; 2510 } 2511 2512 if (qualifier == 'L') 2513 spec->type = FORMAT_TYPE_LONG_LONG; 2514 else if (qualifier == 'l') { 2515 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2516 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2517 } else if (qualifier == 'z') { 2518 spec->type = FORMAT_TYPE_SIZE_T; 2519 } else if (qualifier == 't') { 2520 spec->type = FORMAT_TYPE_PTRDIFF; 2521 } else if (qualifier == 'H') { 2522 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2523 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2524 } else if (qualifier == 'h') { 2525 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2526 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2527 } else { 2528 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2529 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2530 } 2531 2532 return ++fmt - start; 2533} 2534 2535static void 2536set_field_width(struct printf_spec *spec, int width) 2537{ 2538 spec->field_width = width; 2539 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2540 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2541 } 2542} 2543 2544static void 2545set_precision(struct printf_spec *spec, int prec) 2546{ 2547 spec->precision = prec; 2548 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2549 spec->precision = clamp(prec, 0, PRECISION_MAX); 2550 } 2551} 2552 2553/** 2554 * vsnprintf - Format a string and place it in a buffer 2555 * @buf: The buffer to place the result into 2556 * @size: The size of the buffer, including the trailing null space 2557 * @fmt: The format string to use 2558 * @args: Arguments for the format string 2559 * 2560 * This function generally follows C99 vsnprintf, but has some 2561 * extensions and a few limitations: 2562 * 2563 * - ``%n`` is unsupported 2564 * - ``%p*`` is handled by pointer() 2565 * 2566 * See pointer() or Documentation/core-api/printk-formats.rst for more 2567 * extensive description. 2568 * 2569 * **Please update the documentation in both places when making changes** 2570 * 2571 * The return value is the number of characters which would 2572 * be generated for the given input, excluding the trailing 2573 * '\0', as per ISO C99. If you want to have the exact 2574 * number of characters written into @buf as return value 2575 * (not including the trailing '\0'), use vscnprintf(). If the 2576 * return is greater than or equal to @size, the resulting 2577 * string is truncated. 2578 * 2579 * If you're not already dealing with a va_list consider using snprintf(). 2580 */ 2581int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2582{ 2583 unsigned long long num; 2584 char *str, *end; 2585 struct printf_spec spec = {0}; 2586 2587 /* Reject out-of-range values early. Large positive sizes are 2588 used for unknown buffer sizes. */ 2589 if (WARN_ON_ONCE(size > INT_MAX)) 2590 return 0; 2591 2592 str = buf; 2593 end = buf + size; 2594 2595 /* Make sure end is always >= buf */ 2596 if (end < buf) { 2597 end = ((void *)-1); 2598 size = end - buf; 2599 } 2600 2601 while (*fmt) { 2602 const char *old_fmt = fmt; 2603 int read = format_decode(fmt, &spec); 2604 2605 fmt += read; 2606 2607 switch (spec.type) { 2608 case FORMAT_TYPE_NONE: { 2609 int copy = read; 2610 if (str < end) { 2611 if (copy > end - str) 2612 copy = end - str; 2613 memcpy(str, old_fmt, copy); 2614 } 2615 str += read; 2616 break; 2617 } 2618 2619 case FORMAT_TYPE_WIDTH: 2620 set_field_width(&spec, va_arg(args, int)); 2621 break; 2622 2623 case FORMAT_TYPE_PRECISION: 2624 set_precision(&spec, va_arg(args, int)); 2625 break; 2626 2627 case FORMAT_TYPE_CHAR: { 2628 char c; 2629 2630 if (!(spec.flags & LEFT)) { 2631 while (--spec.field_width > 0) { 2632 if (str < end) 2633 *str = ' '; 2634 ++str; 2635 2636 } 2637 } 2638 c = (unsigned char) va_arg(args, int); 2639 if (str < end) 2640 *str = c; 2641 ++str; 2642 while (--spec.field_width > 0) { 2643 if (str < end) 2644 *str = ' '; 2645 ++str; 2646 } 2647 break; 2648 } 2649 2650 case FORMAT_TYPE_STR: 2651 str = string(str, end, va_arg(args, char *), spec); 2652 break; 2653 2654 case FORMAT_TYPE_PTR: 2655 str = pointer(fmt, str, end, va_arg(args, void *), 2656 spec); 2657 while (isalnum(*fmt)) 2658 fmt++; 2659 break; 2660 2661 case FORMAT_TYPE_PERCENT_CHAR: 2662 if (str < end) 2663 *str = '%'; 2664 ++str; 2665 break; 2666 2667 case FORMAT_TYPE_INVALID: 2668 /* 2669 * Presumably the arguments passed gcc's type 2670 * checking, but there is no safe or sane way 2671 * for us to continue parsing the format and 2672 * fetching from the va_list; the remaining 2673 * specifiers and arguments would be out of 2674 * sync. 2675 */ 2676 goto out; 2677 2678 default: 2679 switch (spec.type) { 2680 case FORMAT_TYPE_LONG_LONG: 2681 num = va_arg(args, long long); 2682 break; 2683 case FORMAT_TYPE_ULONG: 2684 num = va_arg(args, unsigned long); 2685 break; 2686 case FORMAT_TYPE_LONG: 2687 num = va_arg(args, long); 2688 break; 2689 case FORMAT_TYPE_SIZE_T: 2690 if (spec.flags & SIGN) 2691 num = va_arg(args, ssize_t); 2692 else 2693 num = va_arg(args, size_t); 2694 break; 2695 case FORMAT_TYPE_PTRDIFF: 2696 num = va_arg(args, ptrdiff_t); 2697 break; 2698 case FORMAT_TYPE_UBYTE: 2699 num = (unsigned char) va_arg(args, int); 2700 break; 2701 case FORMAT_TYPE_BYTE: 2702 num = (signed char) va_arg(args, int); 2703 break; 2704 case FORMAT_TYPE_USHORT: 2705 num = (unsigned short) va_arg(args, int); 2706 break; 2707 case FORMAT_TYPE_SHORT: 2708 num = (short) va_arg(args, int); 2709 break; 2710 case FORMAT_TYPE_INT: 2711 num = (int) va_arg(args, int); 2712 break; 2713 default: 2714 num = va_arg(args, unsigned int); 2715 } 2716 2717 str = number(str, end, num, spec); 2718 } 2719 } 2720 2721out: 2722 if (size > 0) { 2723 if (str < end) 2724 *str = '\0'; 2725 else 2726 end[-1] = '\0'; 2727 } 2728 2729 /* the trailing null byte doesn't count towards the total */ 2730 return str-buf; 2731 2732} 2733EXPORT_SYMBOL(vsnprintf); 2734 2735/** 2736 * vscnprintf - Format a string and place it in a buffer 2737 * @buf: The buffer to place the result into 2738 * @size: The size of the buffer, including the trailing null space 2739 * @fmt: The format string to use 2740 * @args: Arguments for the format string 2741 * 2742 * The return value is the number of characters which have been written into 2743 * the @buf not including the trailing '\0'. If @size is == 0 the function 2744 * returns 0. 2745 * 2746 * If you're not already dealing with a va_list consider using scnprintf(). 2747 * 2748 * See the vsnprintf() documentation for format string extensions over C99. 2749 */ 2750int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2751{ 2752 int i; 2753 2754 i = vsnprintf(buf, size, fmt, args); 2755 2756 if (likely(i < size)) 2757 return i; 2758 if (size != 0) 2759 return size - 1; 2760 return 0; 2761} 2762EXPORT_SYMBOL(vscnprintf); 2763 2764/** 2765 * snprintf - Format a string and place it in a buffer 2766 * @buf: The buffer to place the result into 2767 * @size: The size of the buffer, including the trailing null space 2768 * @fmt: The format string to use 2769 * @...: Arguments for the format string 2770 * 2771 * The return value is the number of characters which would be 2772 * generated for the given input, excluding the trailing null, 2773 * as per ISO C99. If the return is greater than or equal to 2774 * @size, the resulting string is truncated. 2775 * 2776 * See the vsnprintf() documentation for format string extensions over C99. 2777 */ 2778int snprintf(char *buf, size_t size, const char *fmt, ...) 2779{ 2780 va_list args; 2781 int i; 2782 2783 va_start(args, fmt); 2784 i = vsnprintf(buf, size, fmt, args); 2785 va_end(args); 2786 2787 return i; 2788} 2789EXPORT_SYMBOL(snprintf); 2790 2791/** 2792 * scnprintf - Format a string and place it in a buffer 2793 * @buf: The buffer to place the result into 2794 * @size: The size of the buffer, including the trailing null space 2795 * @fmt: The format string to use 2796 * @...: Arguments for the format string 2797 * 2798 * The return value is the number of characters written into @buf not including 2799 * the trailing '\0'. If @size is == 0 the function returns 0. 2800 */ 2801 2802int scnprintf(char *buf, size_t size, const char *fmt, ...) 2803{ 2804 va_list args; 2805 int i; 2806 2807 va_start(args, fmt); 2808 i = vscnprintf(buf, size, fmt, args); 2809 va_end(args); 2810 2811 return i; 2812} 2813EXPORT_SYMBOL(scnprintf); 2814 2815/** 2816 * vsprintf - Format a string and place it in a buffer 2817 * @buf: The buffer to place the result into 2818 * @fmt: The format string to use 2819 * @args: Arguments for the format string 2820 * 2821 * The function returns the number of characters written 2822 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2823 * buffer overflows. 2824 * 2825 * If you're not already dealing with a va_list consider using sprintf(). 2826 * 2827 * See the vsnprintf() documentation for format string extensions over C99. 2828 */ 2829int vsprintf(char *buf, const char *fmt, va_list args) 2830{ 2831 return vsnprintf(buf, INT_MAX, fmt, args); 2832} 2833EXPORT_SYMBOL(vsprintf); 2834 2835/** 2836 * sprintf - Format a string and place it in a buffer 2837 * @buf: The buffer to place the result into 2838 * @fmt: The format string to use 2839 * @...: Arguments for the format string 2840 * 2841 * The function returns the number of characters written 2842 * into @buf. Use snprintf() or scnprintf() in order to avoid 2843 * buffer overflows. 2844 * 2845 * See the vsnprintf() documentation for format string extensions over C99. 2846 */ 2847int sprintf(char *buf, const char *fmt, ...) 2848{ 2849 va_list args; 2850 int i; 2851 2852 va_start(args, fmt); 2853 i = vsnprintf(buf, INT_MAX, fmt, args); 2854 va_end(args); 2855 2856 return i; 2857} 2858EXPORT_SYMBOL(sprintf); 2859 2860#ifdef CONFIG_BINARY_PRINTF 2861/* 2862 * bprintf service: 2863 * vbin_printf() - VA arguments to binary data 2864 * bstr_printf() - Binary data to text string 2865 */ 2866 2867/** 2868 * vbin_printf - Parse a format string and place args' binary value in a buffer 2869 * @bin_buf: The buffer to place args' binary value 2870 * @size: The size of the buffer(by words(32bits), not characters) 2871 * @fmt: The format string to use 2872 * @args: Arguments for the format string 2873 * 2874 * The format follows C99 vsnprintf, except %n is ignored, and its argument 2875 * is skipped. 2876 * 2877 * The return value is the number of words(32bits) which would be generated for 2878 * the given input. 2879 * 2880 * NOTE: 2881 * If the return value is greater than @size, the resulting bin_buf is NOT 2882 * valid for bstr_printf(). 2883 */ 2884int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 2885{ 2886 struct printf_spec spec = {0}; 2887 char *str, *end; 2888 int width; 2889 2890 str = (char *)bin_buf; 2891 end = (char *)(bin_buf + size); 2892 2893#define save_arg(type) \ 2894({ \ 2895 unsigned long long value; \ 2896 if (sizeof(type) == 8) { \ 2897 unsigned long long val8; \ 2898 str = PTR_ALIGN(str, sizeof(u32)); \ 2899 val8 = va_arg(args, unsigned long long); \ 2900 if (str + sizeof(type) <= end) { \ 2901 *(u32 *)str = *(u32 *)&val8; \ 2902 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 2903 } \ 2904 value = val8; \ 2905 } else { \ 2906 unsigned int val4; \ 2907 str = PTR_ALIGN(str, sizeof(type)); \ 2908 val4 = va_arg(args, int); \ 2909 if (str + sizeof(type) <= end) \ 2910 *(typeof(type) *)str = (type)(long)val4; \ 2911 value = (unsigned long long)val4; \ 2912 } \ 2913 str += sizeof(type); \ 2914 value; \ 2915}) 2916 2917 while (*fmt) { 2918 int read = format_decode(fmt, &spec); 2919 2920 fmt += read; 2921 2922 switch (spec.type) { 2923 case FORMAT_TYPE_NONE: 2924 case FORMAT_TYPE_PERCENT_CHAR: 2925 break; 2926 case FORMAT_TYPE_INVALID: 2927 goto out; 2928 2929 case FORMAT_TYPE_WIDTH: 2930 case FORMAT_TYPE_PRECISION: 2931 width = (int)save_arg(int); 2932 /* Pointers may require the width */ 2933 if (*fmt == 'p') 2934 set_field_width(&spec, width); 2935 break; 2936 2937 case FORMAT_TYPE_CHAR: 2938 save_arg(char); 2939 break; 2940 2941 case FORMAT_TYPE_STR: { 2942 const char *save_str = va_arg(args, char *); 2943 const char *err_msg; 2944 size_t len; 2945 2946 err_msg = check_pointer_msg(save_str); 2947 if (err_msg) 2948 save_str = err_msg; 2949 2950 len = strlen(save_str) + 1; 2951 if (str + len < end) 2952 memcpy(str, save_str, len); 2953 str += len; 2954 break; 2955 } 2956 2957 case FORMAT_TYPE_PTR: 2958 /* Dereferenced pointers must be done now */ 2959 switch (*fmt) { 2960 /* Dereference of functions is still OK */ 2961 case 'S': 2962 case 's': 2963 case 'x': 2964 case 'K': 2965 case 'e': 2966 save_arg(void *); 2967 break; 2968 default: 2969 if (!isalnum(*fmt)) { 2970 save_arg(void *); 2971 break; 2972 } 2973 str = pointer(fmt, str, end, va_arg(args, void *), 2974 spec); 2975 if (str + 1 < end) 2976 *str++ = '\0'; 2977 else 2978 end[-1] = '\0'; /* Must be nul terminated */ 2979 } 2980 /* skip all alphanumeric pointer suffixes */ 2981 while (isalnum(*fmt)) 2982 fmt++; 2983 break; 2984 2985 default: 2986 switch (spec.type) { 2987 2988 case FORMAT_TYPE_LONG_LONG: 2989 save_arg(long long); 2990 break; 2991 case FORMAT_TYPE_ULONG: 2992 case FORMAT_TYPE_LONG: 2993 save_arg(unsigned long); 2994 break; 2995 case FORMAT_TYPE_SIZE_T: 2996 save_arg(size_t); 2997 break; 2998 case FORMAT_TYPE_PTRDIFF: 2999 save_arg(ptrdiff_t); 3000 break; 3001 case FORMAT_TYPE_UBYTE: 3002 case FORMAT_TYPE_BYTE: 3003 save_arg(char); 3004 break; 3005 case FORMAT_TYPE_USHORT: 3006 case FORMAT_TYPE_SHORT: 3007 save_arg(short); 3008 break; 3009 default: 3010 save_arg(int); 3011 } 3012 } 3013 } 3014 3015out: 3016 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3017#undef save_arg 3018} 3019EXPORT_SYMBOL_GPL(vbin_printf); 3020 3021/** 3022 * bstr_printf - Format a string from binary arguments 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 * @bin_buf: Binary arguments for the format string 3027 * 3028 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3029 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3030 * a binary buffer that generated by vbin_printf. 3031 * 3032 * The format follows C99 vsnprintf, but has some extensions: 3033 * see vsnprintf comment for details. 3034 * 3035 * The return value is the number of characters which would 3036 * be generated for the given input, excluding the trailing 3037 * '\0', as per ISO C99. If you want to have the exact 3038 * number of characters written into @buf as return value 3039 * (not including the trailing '\0'), use vscnprintf(). If the 3040 * return is greater than or equal to @size, the resulting 3041 * string is truncated. 3042 */ 3043int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 3044{ 3045 struct printf_spec spec = {0}; 3046 char *str, *end; 3047 const char *args = (const char *)bin_buf; 3048 3049 if (WARN_ON_ONCE(size > INT_MAX)) 3050 return 0; 3051 3052 str = buf; 3053 end = buf + size; 3054 3055#define get_arg(type) \ 3056({ \ 3057 typeof(type) value; \ 3058 if (sizeof(type) == 8) { \ 3059 args = PTR_ALIGN(args, sizeof(u32)); \ 3060 *(u32 *)&value = *(u32 *)args; \ 3061 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3062 } else { \ 3063 args = PTR_ALIGN(args, sizeof(type)); \ 3064 value = *(typeof(type) *)args; \ 3065 } \ 3066 args += sizeof(type); \ 3067 value; \ 3068}) 3069 3070 /* Make sure end is always >= buf */ 3071 if (end < buf) { 3072 end = ((void *)-1); 3073 size = end - buf; 3074 } 3075 3076 while (*fmt) { 3077 const char *old_fmt = fmt; 3078 int read = format_decode(fmt, &spec); 3079 3080 fmt += read; 3081 3082 switch (spec.type) { 3083 case FORMAT_TYPE_NONE: { 3084 int copy = read; 3085 if (str < end) { 3086 if (copy > end - str) 3087 copy = end - str; 3088 memcpy(str, old_fmt, copy); 3089 } 3090 str += read; 3091 break; 3092 } 3093 3094 case FORMAT_TYPE_WIDTH: 3095 set_field_width(&spec, get_arg(int)); 3096 break; 3097 3098 case FORMAT_TYPE_PRECISION: 3099 set_precision(&spec, get_arg(int)); 3100 break; 3101 3102 case FORMAT_TYPE_CHAR: { 3103 char c; 3104 3105 if (!(spec.flags & LEFT)) { 3106 while (--spec.field_width > 0) { 3107 if (str < end) 3108 *str = ' '; 3109 ++str; 3110 } 3111 } 3112 c = (unsigned char) get_arg(char); 3113 if (str < end) 3114 *str = c; 3115 ++str; 3116 while (--spec.field_width > 0) { 3117 if (str < end) 3118 *str = ' '; 3119 ++str; 3120 } 3121 break; 3122 } 3123 3124 case FORMAT_TYPE_STR: { 3125 const char *str_arg = args; 3126 args += strlen(str_arg) + 1; 3127 str = string(str, end, (char *)str_arg, spec); 3128 break; 3129 } 3130 3131 case FORMAT_TYPE_PTR: { 3132 bool process = false; 3133 int copy, len; 3134 /* Non function dereferences were already done */ 3135 switch (*fmt) { 3136 case 'S': 3137 case 's': 3138 case 'x': 3139 case 'K': 3140 case 'e': 3141 process = true; 3142 break; 3143 default: 3144 if (!isalnum(*fmt)) { 3145 process = true; 3146 break; 3147 } 3148 /* Pointer dereference was already processed */ 3149 if (str < end) { 3150 len = copy = strlen(args); 3151 if (copy > end - str) 3152 copy = end - str; 3153 memcpy(str, args, copy); 3154 str += len; 3155 args += len + 1; 3156 } 3157 } 3158 if (process) 3159 str = pointer(fmt, str, end, get_arg(void *), spec); 3160 3161 while (isalnum(*fmt)) 3162 fmt++; 3163 break; 3164 } 3165 3166 case FORMAT_TYPE_PERCENT_CHAR: 3167 if (str < end) 3168 *str = '%'; 3169 ++str; 3170 break; 3171 3172 case FORMAT_TYPE_INVALID: 3173 goto out; 3174 3175 default: { 3176 unsigned long long num; 3177 3178 switch (spec.type) { 3179 3180 case FORMAT_TYPE_LONG_LONG: 3181 num = get_arg(long long); 3182 break; 3183 case FORMAT_TYPE_ULONG: 3184 case FORMAT_TYPE_LONG: 3185 num = get_arg(unsigned long); 3186 break; 3187 case FORMAT_TYPE_SIZE_T: 3188 num = get_arg(size_t); 3189 break; 3190 case FORMAT_TYPE_PTRDIFF: 3191 num = get_arg(ptrdiff_t); 3192 break; 3193 case FORMAT_TYPE_UBYTE: 3194 num = get_arg(unsigned char); 3195 break; 3196 case FORMAT_TYPE_BYTE: 3197 num = get_arg(signed char); 3198 break; 3199 case FORMAT_TYPE_USHORT: 3200 num = get_arg(unsigned short); 3201 break; 3202 case FORMAT_TYPE_SHORT: 3203 num = get_arg(short); 3204 break; 3205 case FORMAT_TYPE_UINT: 3206 num = get_arg(unsigned int); 3207 break; 3208 default: 3209 num = get_arg(int); 3210 } 3211 3212 str = number(str, end, num, spec); 3213 } /* default: */ 3214 } /* switch(spec.type) */ 3215 } /* while(*fmt) */ 3216 3217out: 3218 if (size > 0) { 3219 if (str < end) 3220 *str = '\0'; 3221 else 3222 end[-1] = '\0'; 3223 } 3224 3225#undef get_arg 3226 3227 /* the trailing null byte doesn't count towards the total */ 3228 return str - buf; 3229} 3230EXPORT_SYMBOL_GPL(bstr_printf); 3231 3232/** 3233 * bprintf - Parse a format string and place args' binary value in a buffer 3234 * @bin_buf: The buffer to place args' binary value 3235 * @size: The size of the buffer(by words(32bits), not characters) 3236 * @fmt: The format string to use 3237 * @...: Arguments for the format string 3238 * 3239 * The function returns the number of words(u32) written 3240 * into @bin_buf. 3241 */ 3242int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 3243{ 3244 va_list args; 3245 int ret; 3246 3247 va_start(args, fmt); 3248 ret = vbin_printf(bin_buf, size, fmt, args); 3249 va_end(args); 3250 3251 return ret; 3252} 3253EXPORT_SYMBOL_GPL(bprintf); 3254 3255#endif /* CONFIG_BINARY_PRINTF */ 3256 3257/** 3258 * vsscanf - Unformat a buffer into a list of arguments 3259 * @buf: input buffer 3260 * @fmt: format of buffer 3261 * @args: arguments 3262 */ 3263int vsscanf(const char *buf, const char *fmt, va_list args) 3264{ 3265 const char *str = buf; 3266 char *next; 3267 char digit; 3268 int num = 0; 3269 u8 qualifier; 3270 unsigned int base; 3271 union { 3272 long long s; 3273 unsigned long long u; 3274 } val; 3275 s16 field_width; 3276 bool is_sign; 3277 3278 while (*fmt) { 3279 /* skip any white space in format */ 3280 /* white space in format matchs any amount of 3281 * white space, including none, in the input. 3282 */ 3283 if (isspace(*fmt)) { 3284 fmt = skip_spaces(++fmt); 3285 str = skip_spaces(str); 3286 } 3287 3288 /* anything that is not a conversion must match exactly */ 3289 if (*fmt != '%' && *fmt) { 3290 if (*fmt++ != *str++) 3291 break; 3292 continue; 3293 } 3294 3295 if (!*fmt) 3296 break; 3297 ++fmt; 3298 3299 /* skip this conversion. 3300 * advance both strings to next white space 3301 */ 3302 if (*fmt == '*') { 3303 if (!*str) 3304 break; 3305 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3306 /* '%*[' not yet supported, invalid format */ 3307 if (*fmt == '[') 3308 return num; 3309 fmt++; 3310 } 3311 while (!isspace(*str) && *str) 3312 str++; 3313 continue; 3314 } 3315 3316 /* get field width */ 3317 field_width = -1; 3318 if (isdigit(*fmt)) { 3319 field_width = skip_atoi(&fmt); 3320 if (field_width <= 0) 3321 break; 3322 } 3323 3324 /* get conversion qualifier */ 3325 qualifier = -1; 3326 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3327 *fmt == 'z') { 3328 qualifier = *fmt++; 3329 if (unlikely(qualifier == *fmt)) { 3330 if (qualifier == 'h') { 3331 qualifier = 'H'; 3332 fmt++; 3333 } else if (qualifier == 'l') { 3334 qualifier = 'L'; 3335 fmt++; 3336 } 3337 } 3338 } 3339 3340 if (!*fmt) 3341 break; 3342 3343 if (*fmt == 'n') { 3344 /* return number of characters read so far */ 3345 *va_arg(args, int *) = str - buf; 3346 ++fmt; 3347 continue; 3348 } 3349 3350 if (!*str) 3351 break; 3352 3353 base = 10; 3354 is_sign = false; 3355 3356 switch (*fmt++) { 3357 case 'c': 3358 { 3359 char *s = (char *)va_arg(args, char*); 3360 if (field_width == -1) 3361 field_width = 1; 3362 do { 3363 *s++ = *str++; 3364 } while (--field_width > 0 && *str); 3365 num++; 3366 } 3367 continue; 3368 case 's': 3369 { 3370 char *s = (char *)va_arg(args, char *); 3371 if (field_width == -1) 3372 field_width = SHRT_MAX; 3373 /* first, skip leading white space in buffer */ 3374 str = skip_spaces(str); 3375 3376 /* now copy until next white space */ 3377 while (*str && !isspace(*str) && field_width--) 3378 *s++ = *str++; 3379 *s = '\0'; 3380 num++; 3381 } 3382 continue; 3383 /* 3384 * Warning: This implementation of the '[' conversion specifier 3385 * deviates from its glibc counterpart in the following ways: 3386 * (1) It does NOT support ranges i.e. '-' is NOT a special 3387 * character 3388 * (2) It cannot match the closing bracket ']' itself 3389 * (3) A field width is required 3390 * (4) '%*[' (discard matching input) is currently not supported 3391 * 3392 * Example usage: 3393 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3394 * buf1, buf2, buf3); 3395 * if (ret < 3) 3396 * // etc.. 3397 */ 3398 case '[': 3399 { 3400 char *s = (char *)va_arg(args, char *); 3401 DECLARE_BITMAP(set, 256) = {0}; 3402 unsigned int len = 0; 3403 bool negate = (*fmt == '^'); 3404 3405 /* field width is required */ 3406 if (field_width == -1) 3407 return num; 3408 3409 if (negate) 3410 ++fmt; 3411 3412 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3413 set_bit((u8)*fmt, set); 3414 3415 /* no ']' or no character set found */ 3416 if (!*fmt || !len) 3417 return num; 3418 ++fmt; 3419 3420 if (negate) { 3421 bitmap_complement(set, set, 256); 3422 /* exclude null '\0' byte */ 3423 clear_bit(0, set); 3424 } 3425 3426 /* match must be non-empty */ 3427 if (!test_bit((u8)*str, set)) 3428 return num; 3429 3430 while (test_bit((u8)*str, set) && field_width--) 3431 *s++ = *str++; 3432 *s = '\0'; 3433 ++num; 3434 } 3435 continue; 3436 case 'o': 3437 base = 8; 3438 break; 3439 case 'x': 3440 case 'X': 3441 base = 16; 3442 break; 3443 case 'i': 3444 base = 0; 3445 /* fall through */ 3446 case 'd': 3447 is_sign = true; 3448 /* fall through */ 3449 case 'u': 3450 break; 3451 case '%': 3452 /* looking for '%' in str */ 3453 if (*str++ != '%') 3454 return num; 3455 continue; 3456 default: 3457 /* invalid format; stop here */ 3458 return num; 3459 } 3460 3461 /* have some sort of integer conversion. 3462 * first, skip white space in buffer. 3463 */ 3464 str = skip_spaces(str); 3465 3466 digit = *str; 3467 if (is_sign && digit == '-') 3468 digit = *(str + 1); 3469 3470 if (!digit 3471 || (base == 16 && !isxdigit(digit)) 3472 || (base == 10 && !isdigit(digit)) 3473 || (base == 8 && (!isdigit(digit) || digit > '7')) 3474 || (base == 0 && !isdigit(digit))) 3475 break; 3476 3477 if (is_sign) 3478 val.s = simple_strntoll(str, 3479 field_width >= 0 ? field_width : INT_MAX, 3480 &next, base); 3481 else 3482 val.u = simple_strntoull(str, 3483 field_width >= 0 ? field_width : INT_MAX, 3484 &next, base); 3485 3486 switch (qualifier) { 3487 case 'H': /* that's 'hh' in format */ 3488 if (is_sign) 3489 *va_arg(args, signed char *) = val.s; 3490 else 3491 *va_arg(args, unsigned char *) = val.u; 3492 break; 3493 case 'h': 3494 if (is_sign) 3495 *va_arg(args, short *) = val.s; 3496 else 3497 *va_arg(args, unsigned short *) = val.u; 3498 break; 3499 case 'l': 3500 if (is_sign) 3501 *va_arg(args, long *) = val.s; 3502 else 3503 *va_arg(args, unsigned long *) = val.u; 3504 break; 3505 case 'L': 3506 if (is_sign) 3507 *va_arg(args, long long *) = val.s; 3508 else 3509 *va_arg(args, unsigned long long *) = val.u; 3510 break; 3511 case 'z': 3512 *va_arg(args, size_t *) = val.u; 3513 break; 3514 default: 3515 if (is_sign) 3516 *va_arg(args, int *) = val.s; 3517 else 3518 *va_arg(args, unsigned int *) = val.u; 3519 break; 3520 } 3521 num++; 3522 3523 if (!next) 3524 break; 3525 str = next; 3526 } 3527 3528 return num; 3529} 3530EXPORT_SYMBOL(vsscanf); 3531 3532/** 3533 * sscanf - Unformat a buffer into a list of arguments 3534 * @buf: input buffer 3535 * @fmt: formatting of buffer 3536 * @...: resulting arguments 3537 */ 3538int sscanf(const char *buf, const char *fmt, ...) 3539{ 3540 va_list args; 3541 int i; 3542 3543 va_start(args, fmt); 3544 i = vsscanf(buf, fmt, args); 3545 va_end(args); 3546 3547 return i; 3548} 3549EXPORT_SYMBOL(sscanf); 3550