1 /* 2 * linux/lib/vsprintf.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 */ 6 7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ 8 /* 9 * Wirzenius wrote this portably, Torvalds fucked it up :-) 10 */ 11 12 /* 13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com> 14 * - changed to provide snprintf and vsnprintf functions 15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> 16 * - scnprintf and vscnprintf 17 */ 18 19 #include <stdarg.h> 20 #include <linux/clk.h> 21 #include <linux/clk-provider.h> 22 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */ 23 #include <linux/types.h> 24 #include <linux/string.h> 25 #include <linux/ctype.h> 26 #include <linux/kernel.h> 27 #include <linux/kallsyms.h> 28 #include <linux/math64.h> 29 #include <linux/uaccess.h> 30 #include <linux/ioport.h> 31 #include <linux/dcache.h> 32 #include <linux/cred.h> 33 #include <linux/uuid.h> 34 #include <linux/of.h> 35 #include <net/addrconf.h> 36 #include <linux/siphash.h> 37 #include <linux/compiler.h> 38 #ifdef CONFIG_BLOCK 39 #include <linux/blkdev.h> 40 #endif 41 42 #include "../mm/internal.h" /* For the trace_print_flags arrays */ 43 44 #include <asm/page.h> /* for PAGE_SIZE */ 45 #include <asm/sections.h> /* for dereference_function_descriptor() */ 46 #include <asm/byteorder.h> /* cpu_to_le16 */ 47 48 #include <linux/string_helpers.h> 49 #include "kstrtox.h" 50 51 /** 52 * simple_strtoull - convert a string to an unsigned long long 53 * @cp: The start of the string 54 * @endp: A pointer to the end of the parsed string will be placed here 55 * @base: The number base to use 56 * 57 * This function is obsolete. Please use kstrtoull instead. 58 */ 59 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 60 { 61 unsigned long long result; 62 unsigned int rv; 63 64 cp = _parse_integer_fixup_radix(cp, &base); 65 rv = _parse_integer(cp, base, &result); 66 /* FIXME */ 67 cp += (rv & ~KSTRTOX_OVERFLOW); 68 69 if (endp) 70 *endp = (char *)cp; 71 72 return result; 73 } 74 EXPORT_SYMBOL(simple_strtoull); 75 76 /** 77 * simple_strtoul - convert a string to an unsigned long 78 * @cp: The start of the string 79 * @endp: A pointer to the end of the parsed string will be placed here 80 * @base: The number base to use 81 * 82 * This function is obsolete. Please use kstrtoul instead. 83 */ 84 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 85 { 86 return simple_strtoull(cp, endp, base); 87 } 88 EXPORT_SYMBOL(simple_strtoul); 89 90 /** 91 * simple_strtol - convert a string to a signed long 92 * @cp: The start of the string 93 * @endp: A pointer to the end of the parsed string will be placed here 94 * @base: The number base to use 95 * 96 * This function is obsolete. Please use kstrtol instead. 97 */ 98 long simple_strtol(const char *cp, char **endp, unsigned int base) 99 { 100 if (*cp == '-') 101 return -simple_strtoul(cp + 1, endp, base); 102 103 return simple_strtoul(cp, endp, base); 104 } 105 EXPORT_SYMBOL(simple_strtol); 106 107 /** 108 * simple_strtoll - convert a string to a signed long long 109 * @cp: The start of the string 110 * @endp: A pointer to the end of the parsed string will be placed here 111 * @base: The number base to use 112 * 113 * This function is obsolete. Please use kstrtoll instead. 114 */ 115 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 116 { 117 if (*cp == '-') 118 return -simple_strtoull(cp + 1, endp, base); 119 120 return simple_strtoull(cp, endp, base); 121 } 122 EXPORT_SYMBOL(simple_strtoll); 123 124 static noinline_for_stack 125 int skip_atoi(const char **s) 126 { 127 int i = 0; 128 129 do { 130 i = i*10 + *((*s)++) - '0'; 131 } while (isdigit(**s)); 132 133 return i; 134 } 135 136 /* 137 * Decimal conversion is by far the most typical, and is used for 138 * /proc and /sys data. This directly impacts e.g. top performance 139 * with many processes running. We optimize it for speed by emitting 140 * two characters at a time, using a 200 byte lookup table. This 141 * roughly halves the number of multiplications compared to computing 142 * the digits one at a time. Implementation strongly inspired by the 143 * previous version, which in turn used ideas described at 144 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 145 * from the author, Douglas W. Jones). 146 * 147 * It turns out there is precisely one 26 bit fixed-point 148 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 149 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 150 * range happens to be somewhat larger (x <= 1073741898), but that's 151 * irrelevant for our purpose. 152 * 153 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 154 * need a 32x32->64 bit multiply, so we simply use the same constant. 155 * 156 * For dividing a number in the range [100, 10^4-1] by 100, there are 157 * several options. The simplest is (x * 0x147b) >> 19, which is valid 158 * for all x <= 43698. 159 */ 160 161 static const u16 decpair[100] = { 162 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 163 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 164 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 165 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 166 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 167 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 168 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 169 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 170 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 171 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 172 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 173 #undef _ 174 }; 175 176 /* 177 * This will print a single '0' even if r == 0, since we would 178 * immediately jump to out_r where two 0s would be written but only 179 * one of them accounted for in buf. This is needed by ip4_string 180 * below. All other callers pass a non-zero value of r. 181 */ 182 static noinline_for_stack 183 char *put_dec_trunc8(char *buf, unsigned r) 184 { 185 unsigned q; 186 187 /* 1 <= r < 10^8 */ 188 if (r < 100) 189 goto out_r; 190 191 /* 100 <= r < 10^8 */ 192 q = (r * (u64)0x28f5c29) >> 32; 193 *((u16 *)buf) = decpair[r - 100*q]; 194 buf += 2; 195 196 /* 1 <= q < 10^6 */ 197 if (q < 100) 198 goto out_q; 199 200 /* 100 <= q < 10^6 */ 201 r = (q * (u64)0x28f5c29) >> 32; 202 *((u16 *)buf) = decpair[q - 100*r]; 203 buf += 2; 204 205 /* 1 <= r < 10^4 */ 206 if (r < 100) 207 goto out_r; 208 209 /* 100 <= r < 10^4 */ 210 q = (r * 0x147b) >> 19; 211 *((u16 *)buf) = decpair[r - 100*q]; 212 buf += 2; 213 out_q: 214 /* 1 <= q < 100 */ 215 r = q; 216 out_r: 217 /* 1 <= r < 100 */ 218 *((u16 *)buf) = decpair[r]; 219 buf += r < 10 ? 1 : 2; 220 return buf; 221 } 222 223 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 224 static noinline_for_stack 225 char *put_dec_full8(char *buf, unsigned r) 226 { 227 unsigned q; 228 229 /* 0 <= r < 10^8 */ 230 q = (r * (u64)0x28f5c29) >> 32; 231 *((u16 *)buf) = decpair[r - 100*q]; 232 buf += 2; 233 234 /* 0 <= q < 10^6 */ 235 r = (q * (u64)0x28f5c29) >> 32; 236 *((u16 *)buf) = decpair[q - 100*r]; 237 buf += 2; 238 239 /* 0 <= r < 10^4 */ 240 q = (r * 0x147b) >> 19; 241 *((u16 *)buf) = decpair[r - 100*q]; 242 buf += 2; 243 244 /* 0 <= q < 100 */ 245 *((u16 *)buf) = decpair[q]; 246 buf += 2; 247 return buf; 248 } 249 250 static noinline_for_stack 251 char *put_dec(char *buf, unsigned long long n) 252 { 253 if (n >= 100*1000*1000) 254 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 255 /* 1 <= n <= 1.6e11 */ 256 if (n >= 100*1000*1000) 257 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 258 /* 1 <= n < 1e8 */ 259 return put_dec_trunc8(buf, n); 260 } 261 262 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 263 264 static void 265 put_dec_full4(char *buf, unsigned r) 266 { 267 unsigned q; 268 269 /* 0 <= r < 10^4 */ 270 q = (r * 0x147b) >> 19; 271 *((u16 *)buf) = decpair[r - 100*q]; 272 buf += 2; 273 /* 0 <= q < 100 */ 274 *((u16 *)buf) = decpair[q]; 275 } 276 277 /* 278 * Call put_dec_full4 on x % 10000, return x / 10000. 279 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 280 * holds for all x < 1,128,869,999. The largest value this 281 * helper will ever be asked to convert is 1,125,520,955. 282 * (second call in the put_dec code, assuming n is all-ones). 283 */ 284 static noinline_for_stack 285 unsigned put_dec_helper4(char *buf, unsigned x) 286 { 287 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 288 289 put_dec_full4(buf, x - q * 10000); 290 return q; 291 } 292 293 /* Based on code by Douglas W. Jones found at 294 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 295 * (with permission from the author). 296 * Performs no 64-bit division and hence should be fast on 32-bit machines. 297 */ 298 static 299 char *put_dec(char *buf, unsigned long long n) 300 { 301 uint32_t d3, d2, d1, q, h; 302 303 if (n < 100*1000*1000) 304 return put_dec_trunc8(buf, n); 305 306 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 307 h = (n >> 32); 308 d2 = (h ) & 0xffff; 309 d3 = (h >> 16); /* implicit "& 0xffff" */ 310 311 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 312 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 313 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 314 q = put_dec_helper4(buf, q); 315 316 q += 7671 * d3 + 9496 * d2 + 6 * d1; 317 q = put_dec_helper4(buf+4, q); 318 319 q += 4749 * d3 + 42 * d2; 320 q = put_dec_helper4(buf+8, q); 321 322 q += 281 * d3; 323 buf += 12; 324 if (q) 325 buf = put_dec_trunc8(buf, q); 326 else while (buf[-1] == '0') 327 --buf; 328 329 return buf; 330 } 331 332 #endif 333 334 /* 335 * Convert passed number to decimal string. 336 * Returns the length of string. On buffer overflow, returns 0. 337 * 338 * If speed is not important, use snprintf(). It's easy to read the code. 339 */ 340 int num_to_str(char *buf, int size, unsigned long long num) 341 { 342 /* put_dec requires 2-byte alignment of the buffer. */ 343 char tmp[sizeof(num) * 3] __aligned(2); 344 int idx, len; 345 346 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 347 if (num <= 9) { 348 tmp[0] = '0' + num; 349 len = 1; 350 } else { 351 len = put_dec(tmp, num) - tmp; 352 } 353 354 if (len > size) 355 return 0; 356 for (idx = 0; idx < len; ++idx) 357 buf[idx] = tmp[len - idx - 1]; 358 return len; 359 } 360 361 #define SIGN 1 /* unsigned/signed, must be 1 */ 362 #define LEFT 2 /* left justified */ 363 #define PLUS 4 /* show plus */ 364 #define SPACE 8 /* space if plus */ 365 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 366 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 367 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 368 369 enum format_type { 370 FORMAT_TYPE_NONE, /* Just a string part */ 371 FORMAT_TYPE_WIDTH, 372 FORMAT_TYPE_PRECISION, 373 FORMAT_TYPE_CHAR, 374 FORMAT_TYPE_STR, 375 FORMAT_TYPE_PTR, 376 FORMAT_TYPE_PERCENT_CHAR, 377 FORMAT_TYPE_INVALID, 378 FORMAT_TYPE_LONG_LONG, 379 FORMAT_TYPE_ULONG, 380 FORMAT_TYPE_LONG, 381 FORMAT_TYPE_UBYTE, 382 FORMAT_TYPE_BYTE, 383 FORMAT_TYPE_USHORT, 384 FORMAT_TYPE_SHORT, 385 FORMAT_TYPE_UINT, 386 FORMAT_TYPE_INT, 387 FORMAT_TYPE_SIZE_T, 388 FORMAT_TYPE_PTRDIFF 389 }; 390 391 struct printf_spec { 392 unsigned int type:8; /* format_type enum */ 393 signed int field_width:24; /* width of output field */ 394 unsigned int flags:8; /* flags to number() */ 395 unsigned int base:8; /* number base, 8, 10 or 16 only */ 396 signed int precision:16; /* # of digits/chars */ 397 } __packed; 398 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 399 #define PRECISION_MAX ((1 << 15) - 1) 400 401 static noinline_for_stack 402 char *number(char *buf, char *end, unsigned long long num, 403 struct printf_spec spec) 404 { 405 /* put_dec requires 2-byte alignment of the buffer. */ 406 char tmp[3 * sizeof(num)] __aligned(2); 407 char sign; 408 char locase; 409 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 410 int i; 411 bool is_zero = num == 0LL; 412 int field_width = spec.field_width; 413 int precision = spec.precision; 414 415 BUILD_BUG_ON(sizeof(struct printf_spec) != 8); 416 417 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 418 * produces same digits or (maybe lowercased) letters */ 419 locase = (spec.flags & SMALL); 420 if (spec.flags & LEFT) 421 spec.flags &= ~ZEROPAD; 422 sign = 0; 423 if (spec.flags & SIGN) { 424 if ((signed long long)num < 0) { 425 sign = '-'; 426 num = -(signed long long)num; 427 field_width--; 428 } else if (spec.flags & PLUS) { 429 sign = '+'; 430 field_width--; 431 } else if (spec.flags & SPACE) { 432 sign = ' '; 433 field_width--; 434 } 435 } 436 if (need_pfx) { 437 if (spec.base == 16) 438 field_width -= 2; 439 else if (!is_zero) 440 field_width--; 441 } 442 443 /* generate full string in tmp[], in reverse order */ 444 i = 0; 445 if (num < spec.base) 446 tmp[i++] = hex_asc_upper[num] | locase; 447 else if (spec.base != 10) { /* 8 or 16 */ 448 int mask = spec.base - 1; 449 int shift = 3; 450 451 if (spec.base == 16) 452 shift = 4; 453 do { 454 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 455 num >>= shift; 456 } while (num); 457 } else { /* base 10 */ 458 i = put_dec(tmp, num) - tmp; 459 } 460 461 /* printing 100 using %2d gives "100", not "00" */ 462 if (i > precision) 463 precision = i; 464 /* leading space padding */ 465 field_width -= precision; 466 if (!(spec.flags & (ZEROPAD | LEFT))) { 467 while (--field_width >= 0) { 468 if (buf < end) 469 *buf = ' '; 470 ++buf; 471 } 472 } 473 /* sign */ 474 if (sign) { 475 if (buf < end) 476 *buf = sign; 477 ++buf; 478 } 479 /* "0x" / "0" prefix */ 480 if (need_pfx) { 481 if (spec.base == 16 || !is_zero) { 482 if (buf < end) 483 *buf = '0'; 484 ++buf; 485 } 486 if (spec.base == 16) { 487 if (buf < end) 488 *buf = ('X' | locase); 489 ++buf; 490 } 491 } 492 /* zero or space padding */ 493 if (!(spec.flags & LEFT)) { 494 char c = ' ' + (spec.flags & ZEROPAD); 495 BUILD_BUG_ON(' ' + ZEROPAD != '0'); 496 while (--field_width >= 0) { 497 if (buf < end) 498 *buf = c; 499 ++buf; 500 } 501 } 502 /* hmm even more zero padding? */ 503 while (i <= --precision) { 504 if (buf < end) 505 *buf = '0'; 506 ++buf; 507 } 508 /* actual digits of result */ 509 while (--i >= 0) { 510 if (buf < end) 511 *buf = tmp[i]; 512 ++buf; 513 } 514 /* trailing space padding */ 515 while (--field_width >= 0) { 516 if (buf < end) 517 *buf = ' '; 518 ++buf; 519 } 520 521 return buf; 522 } 523 524 static noinline_for_stack 525 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 526 { 527 struct printf_spec spec; 528 529 spec.type = FORMAT_TYPE_PTR; 530 spec.field_width = 2 + 2 * size; /* 0x + hex */ 531 spec.flags = SPECIAL | SMALL | ZEROPAD; 532 spec.base = 16; 533 spec.precision = -1; 534 535 return number(buf, end, num, spec); 536 } 537 538 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 539 { 540 size_t size; 541 if (buf >= end) /* nowhere to put anything */ 542 return; 543 size = end - buf; 544 if (size <= spaces) { 545 memset(buf, ' ', size); 546 return; 547 } 548 if (len) { 549 if (len > size - spaces) 550 len = size - spaces; 551 memmove(buf + spaces, buf, len); 552 } 553 memset(buf, ' ', spaces); 554 } 555 556 /* 557 * Handle field width padding for a string. 558 * @buf: current buffer position 559 * @n: length of string 560 * @end: end of output buffer 561 * @spec: for field width and flags 562 * Returns: new buffer position after padding. 563 */ 564 static noinline_for_stack 565 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 566 { 567 unsigned spaces; 568 569 if (likely(n >= spec.field_width)) 570 return buf; 571 /* we want to pad the sucker */ 572 spaces = spec.field_width - n; 573 if (!(spec.flags & LEFT)) { 574 move_right(buf - n, end, n, spaces); 575 return buf + spaces; 576 } 577 while (spaces--) { 578 if (buf < end) 579 *buf = ' '; 580 ++buf; 581 } 582 return buf; 583 } 584 585 static noinline_for_stack 586 char *string(char *buf, char *end, const char *s, struct printf_spec spec) 587 { 588 int len = 0; 589 size_t lim = spec.precision; 590 591 if ((unsigned long)s < PAGE_SIZE) 592 s = "(null)"; 593 594 while (lim--) { 595 char c = *s++; 596 if (!c) 597 break; 598 if (buf < end) 599 *buf = c; 600 ++buf; 601 ++len; 602 } 603 return widen_string(buf, len, end, spec); 604 } 605 606 static noinline_for_stack 607 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 608 const char *fmt) 609 { 610 const char *array[4], *s; 611 const struct dentry *p; 612 int depth; 613 int i, n; 614 615 switch (fmt[1]) { 616 case '2': case '3': case '4': 617 depth = fmt[1] - '0'; 618 break; 619 default: 620 depth = 1; 621 } 622 623 rcu_read_lock(); 624 for (i = 0; i < depth; i++, d = p) { 625 p = READ_ONCE(d->d_parent); 626 array[i] = READ_ONCE(d->d_name.name); 627 if (p == d) { 628 if (i) 629 array[i] = ""; 630 i++; 631 break; 632 } 633 } 634 s = array[--i]; 635 for (n = 0; n != spec.precision; n++, buf++) { 636 char c = *s++; 637 if (!c) { 638 if (!i) 639 break; 640 c = '/'; 641 s = array[--i]; 642 } 643 if (buf < end) 644 *buf = c; 645 } 646 rcu_read_unlock(); 647 return widen_string(buf, n, end, spec); 648 } 649 650 #ifdef CONFIG_BLOCK 651 static noinline_for_stack 652 char *bdev_name(char *buf, char *end, struct block_device *bdev, 653 struct printf_spec spec, const char *fmt) 654 { 655 struct gendisk *hd = bdev->bd_disk; 656 657 buf = string(buf, end, hd->disk_name, spec); 658 if (bdev->bd_part->partno) { 659 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 660 if (buf < end) 661 *buf = 'p'; 662 buf++; 663 } 664 buf = number(buf, end, bdev->bd_part->partno, spec); 665 } 666 return buf; 667 } 668 #endif 669 670 static noinline_for_stack 671 char *symbol_string(char *buf, char *end, void *ptr, 672 struct printf_spec spec, const char *fmt) 673 { 674 unsigned long value; 675 #ifdef CONFIG_KALLSYMS 676 char sym[KSYM_SYMBOL_LEN]; 677 #endif 678 679 if (fmt[1] == 'R') 680 ptr = __builtin_extract_return_addr(ptr); 681 value = (unsigned long)ptr; 682 683 #ifdef CONFIG_KALLSYMS 684 if (*fmt == 'B') 685 sprint_backtrace(sym, value); 686 else if (*fmt != 'f' && *fmt != 's') 687 sprint_symbol(sym, value); 688 else 689 sprint_symbol_no_offset(sym, value); 690 691 return string(buf, end, sym, spec); 692 #else 693 return special_hex_number(buf, end, value, sizeof(void *)); 694 #endif 695 } 696 697 static noinline_for_stack 698 char *resource_string(char *buf, char *end, struct resource *res, 699 struct printf_spec spec, const char *fmt) 700 { 701 #ifndef IO_RSRC_PRINTK_SIZE 702 #define IO_RSRC_PRINTK_SIZE 6 703 #endif 704 705 #ifndef MEM_RSRC_PRINTK_SIZE 706 #define MEM_RSRC_PRINTK_SIZE 10 707 #endif 708 static const struct printf_spec io_spec = { 709 .base = 16, 710 .field_width = IO_RSRC_PRINTK_SIZE, 711 .precision = -1, 712 .flags = SPECIAL | SMALL | ZEROPAD, 713 }; 714 static const struct printf_spec mem_spec = { 715 .base = 16, 716 .field_width = MEM_RSRC_PRINTK_SIZE, 717 .precision = -1, 718 .flags = SPECIAL | SMALL | ZEROPAD, 719 }; 720 static const struct printf_spec bus_spec = { 721 .base = 16, 722 .field_width = 2, 723 .precision = -1, 724 .flags = SMALL | ZEROPAD, 725 }; 726 static const struct printf_spec dec_spec = { 727 .base = 10, 728 .precision = -1, 729 .flags = 0, 730 }; 731 static const struct printf_spec str_spec = { 732 .field_width = -1, 733 .precision = 10, 734 .flags = LEFT, 735 }; 736 static const struct printf_spec flag_spec = { 737 .base = 16, 738 .precision = -1, 739 .flags = SPECIAL | SMALL, 740 }; 741 742 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 743 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 744 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 745 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 746 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 747 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 748 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 749 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 750 751 char *p = sym, *pend = sym + sizeof(sym); 752 int decode = (fmt[0] == 'R') ? 1 : 0; 753 const struct printf_spec *specp; 754 755 *p++ = '['; 756 if (res->flags & IORESOURCE_IO) { 757 p = string(p, pend, "io ", str_spec); 758 specp = &io_spec; 759 } else if (res->flags & IORESOURCE_MEM) { 760 p = string(p, pend, "mem ", str_spec); 761 specp = &mem_spec; 762 } else if (res->flags & IORESOURCE_IRQ) { 763 p = string(p, pend, "irq ", str_spec); 764 specp = &dec_spec; 765 } else if (res->flags & IORESOURCE_DMA) { 766 p = string(p, pend, "dma ", str_spec); 767 specp = &dec_spec; 768 } else if (res->flags & IORESOURCE_BUS) { 769 p = string(p, pend, "bus ", str_spec); 770 specp = &bus_spec; 771 } else { 772 p = string(p, pend, "??? ", str_spec); 773 specp = &mem_spec; 774 decode = 0; 775 } 776 if (decode && res->flags & IORESOURCE_UNSET) { 777 p = string(p, pend, "size ", str_spec); 778 p = number(p, pend, resource_size(res), *specp); 779 } else { 780 p = number(p, pend, res->start, *specp); 781 if (res->start != res->end) { 782 *p++ = '-'; 783 p = number(p, pend, res->end, *specp); 784 } 785 } 786 if (decode) { 787 if (res->flags & IORESOURCE_MEM_64) 788 p = string(p, pend, " 64bit", str_spec); 789 if (res->flags & IORESOURCE_PREFETCH) 790 p = string(p, pend, " pref", str_spec); 791 if (res->flags & IORESOURCE_WINDOW) 792 p = string(p, pend, " window", str_spec); 793 if (res->flags & IORESOURCE_DISABLED) 794 p = string(p, pend, " disabled", str_spec); 795 } else { 796 p = string(p, pend, " flags ", str_spec); 797 p = number(p, pend, res->flags, flag_spec); 798 } 799 *p++ = ']'; 800 *p = '\0'; 801 802 return string(buf, end, sym, spec); 803 } 804 805 static noinline_for_stack 806 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 807 const char *fmt) 808 { 809 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 810 negative value, fallback to the default */ 811 char separator; 812 813 if (spec.field_width == 0) 814 /* nothing to print */ 815 return buf; 816 817 if (ZERO_OR_NULL_PTR(addr)) 818 /* NULL pointer */ 819 return string(buf, end, NULL, spec); 820 821 switch (fmt[1]) { 822 case 'C': 823 separator = ':'; 824 break; 825 case 'D': 826 separator = '-'; 827 break; 828 case 'N': 829 separator = 0; 830 break; 831 default: 832 separator = ' '; 833 break; 834 } 835 836 if (spec.field_width > 0) 837 len = min_t(int, spec.field_width, 64); 838 839 for (i = 0; i < len; ++i) { 840 if (buf < end) 841 *buf = hex_asc_hi(addr[i]); 842 ++buf; 843 if (buf < end) 844 *buf = hex_asc_lo(addr[i]); 845 ++buf; 846 847 if (separator && i != len - 1) { 848 if (buf < end) 849 *buf = separator; 850 ++buf; 851 } 852 } 853 854 return buf; 855 } 856 857 static noinline_for_stack 858 char *bitmap_string(char *buf, char *end, unsigned long *bitmap, 859 struct printf_spec spec, const char *fmt) 860 { 861 const int CHUNKSZ = 32; 862 int nr_bits = max_t(int, spec.field_width, 0); 863 int i, chunksz; 864 bool first = true; 865 866 /* reused to print numbers */ 867 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 868 869 chunksz = nr_bits & (CHUNKSZ - 1); 870 if (chunksz == 0) 871 chunksz = CHUNKSZ; 872 873 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 874 for (; i >= 0; i -= CHUNKSZ) { 875 u32 chunkmask, val; 876 int word, bit; 877 878 chunkmask = ((1ULL << chunksz) - 1); 879 word = i / BITS_PER_LONG; 880 bit = i % BITS_PER_LONG; 881 val = (bitmap[word] >> bit) & chunkmask; 882 883 if (!first) { 884 if (buf < end) 885 *buf = ','; 886 buf++; 887 } 888 first = false; 889 890 spec.field_width = DIV_ROUND_UP(chunksz, 4); 891 buf = number(buf, end, val, spec); 892 893 chunksz = CHUNKSZ; 894 } 895 return buf; 896 } 897 898 static noinline_for_stack 899 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap, 900 struct printf_spec spec, const char *fmt) 901 { 902 int nr_bits = max_t(int, spec.field_width, 0); 903 /* current bit is 'cur', most recently seen range is [rbot, rtop] */ 904 int cur, rbot, rtop; 905 bool first = true; 906 907 /* reused to print numbers */ 908 spec = (struct printf_spec){ .base = 10 }; 909 910 rbot = cur = find_first_bit(bitmap, nr_bits); 911 while (cur < nr_bits) { 912 rtop = cur; 913 cur = find_next_bit(bitmap, nr_bits, cur + 1); 914 if (cur < nr_bits && cur <= rtop + 1) 915 continue; 916 917 if (!first) { 918 if (buf < end) 919 *buf = ','; 920 buf++; 921 } 922 first = false; 923 924 buf = number(buf, end, rbot, spec); 925 if (rbot < rtop) { 926 if (buf < end) 927 *buf = '-'; 928 buf++; 929 930 buf = number(buf, end, rtop, spec); 931 } 932 933 rbot = cur; 934 } 935 return buf; 936 } 937 938 static noinline_for_stack 939 char *mac_address_string(char *buf, char *end, u8 *addr, 940 struct printf_spec spec, const char *fmt) 941 { 942 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 943 char *p = mac_addr; 944 int i; 945 char separator; 946 bool reversed = false; 947 948 switch (fmt[1]) { 949 case 'F': 950 separator = '-'; 951 break; 952 953 case 'R': 954 reversed = true; 955 /* fall through */ 956 957 default: 958 separator = ':'; 959 break; 960 } 961 962 for (i = 0; i < 6; i++) { 963 if (reversed) 964 p = hex_byte_pack(p, addr[5 - i]); 965 else 966 p = hex_byte_pack(p, addr[i]); 967 968 if (fmt[0] == 'M' && i != 5) 969 *p++ = separator; 970 } 971 *p = '\0'; 972 973 return string(buf, end, mac_addr, spec); 974 } 975 976 static noinline_for_stack 977 char *ip4_string(char *p, const u8 *addr, const char *fmt) 978 { 979 int i; 980 bool leading_zeros = (fmt[0] == 'i'); 981 int index; 982 int step; 983 984 switch (fmt[2]) { 985 case 'h': 986 #ifdef __BIG_ENDIAN 987 index = 0; 988 step = 1; 989 #else 990 index = 3; 991 step = -1; 992 #endif 993 break; 994 case 'l': 995 index = 3; 996 step = -1; 997 break; 998 case 'n': 999 case 'b': 1000 default: 1001 index = 0; 1002 step = 1; 1003 break; 1004 } 1005 for (i = 0; i < 4; i++) { 1006 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1007 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1008 if (leading_zeros) { 1009 if (digits < 3) 1010 *p++ = '0'; 1011 if (digits < 2) 1012 *p++ = '0'; 1013 } 1014 /* reverse the digits in the quad */ 1015 while (digits--) 1016 *p++ = temp[digits]; 1017 if (i < 3) 1018 *p++ = '.'; 1019 index += step; 1020 } 1021 *p = '\0'; 1022 1023 return p; 1024 } 1025 1026 static noinline_for_stack 1027 char *ip6_compressed_string(char *p, const char *addr) 1028 { 1029 int i, j, range; 1030 unsigned char zerolength[8]; 1031 int longest = 1; 1032 int colonpos = -1; 1033 u16 word; 1034 u8 hi, lo; 1035 bool needcolon = false; 1036 bool useIPv4; 1037 struct in6_addr in6; 1038 1039 memcpy(&in6, addr, sizeof(struct in6_addr)); 1040 1041 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1042 1043 memset(zerolength, 0, sizeof(zerolength)); 1044 1045 if (useIPv4) 1046 range = 6; 1047 else 1048 range = 8; 1049 1050 /* find position of longest 0 run */ 1051 for (i = 0; i < range; i++) { 1052 for (j = i; j < range; j++) { 1053 if (in6.s6_addr16[j] != 0) 1054 break; 1055 zerolength[i]++; 1056 } 1057 } 1058 for (i = 0; i < range; i++) { 1059 if (zerolength[i] > longest) { 1060 longest = zerolength[i]; 1061 colonpos = i; 1062 } 1063 } 1064 if (longest == 1) /* don't compress a single 0 */ 1065 colonpos = -1; 1066 1067 /* emit address */ 1068 for (i = 0; i < range; i++) { 1069 if (i == colonpos) { 1070 if (needcolon || i == 0) 1071 *p++ = ':'; 1072 *p++ = ':'; 1073 needcolon = false; 1074 i += longest - 1; 1075 continue; 1076 } 1077 if (needcolon) { 1078 *p++ = ':'; 1079 needcolon = false; 1080 } 1081 /* hex u16 without leading 0s */ 1082 word = ntohs(in6.s6_addr16[i]); 1083 hi = word >> 8; 1084 lo = word & 0xff; 1085 if (hi) { 1086 if (hi > 0x0f) 1087 p = hex_byte_pack(p, hi); 1088 else 1089 *p++ = hex_asc_lo(hi); 1090 p = hex_byte_pack(p, lo); 1091 } 1092 else if (lo > 0x0f) 1093 p = hex_byte_pack(p, lo); 1094 else 1095 *p++ = hex_asc_lo(lo); 1096 needcolon = true; 1097 } 1098 1099 if (useIPv4) { 1100 if (needcolon) 1101 *p++ = ':'; 1102 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1103 } 1104 *p = '\0'; 1105 1106 return p; 1107 } 1108 1109 static noinline_for_stack 1110 char *ip6_string(char *p, const char *addr, const char *fmt) 1111 { 1112 int i; 1113 1114 for (i = 0; i < 8; i++) { 1115 p = hex_byte_pack(p, *addr++); 1116 p = hex_byte_pack(p, *addr++); 1117 if (fmt[0] == 'I' && i != 7) 1118 *p++ = ':'; 1119 } 1120 *p = '\0'; 1121 1122 return p; 1123 } 1124 1125 static noinline_for_stack 1126 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1127 struct printf_spec spec, const char *fmt) 1128 { 1129 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1130 1131 if (fmt[0] == 'I' && fmt[2] == 'c') 1132 ip6_compressed_string(ip6_addr, addr); 1133 else 1134 ip6_string(ip6_addr, addr, fmt); 1135 1136 return string(buf, end, ip6_addr, spec); 1137 } 1138 1139 static noinline_for_stack 1140 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1141 struct printf_spec spec, const char *fmt) 1142 { 1143 char ip4_addr[sizeof("255.255.255.255")]; 1144 1145 ip4_string(ip4_addr, addr, fmt); 1146 1147 return string(buf, end, ip4_addr, spec); 1148 } 1149 1150 static noinline_for_stack 1151 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1152 struct printf_spec spec, const char *fmt) 1153 { 1154 bool have_p = false, have_s = false, have_f = false, have_c = false; 1155 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1156 sizeof(":12345") + sizeof("/123456789") + 1157 sizeof("%1234567890")]; 1158 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1159 const u8 *addr = (const u8 *) &sa->sin6_addr; 1160 char fmt6[2] = { fmt[0], '6' }; 1161 u8 off = 0; 1162 1163 fmt++; 1164 while (isalpha(*++fmt)) { 1165 switch (*fmt) { 1166 case 'p': 1167 have_p = true; 1168 break; 1169 case 'f': 1170 have_f = true; 1171 break; 1172 case 's': 1173 have_s = true; 1174 break; 1175 case 'c': 1176 have_c = true; 1177 break; 1178 } 1179 } 1180 1181 if (have_p || have_s || have_f) { 1182 *p = '['; 1183 off = 1; 1184 } 1185 1186 if (fmt6[0] == 'I' && have_c) 1187 p = ip6_compressed_string(ip6_addr + off, addr); 1188 else 1189 p = ip6_string(ip6_addr + off, addr, fmt6); 1190 1191 if (have_p || have_s || have_f) 1192 *p++ = ']'; 1193 1194 if (have_p) { 1195 *p++ = ':'; 1196 p = number(p, pend, ntohs(sa->sin6_port), spec); 1197 } 1198 if (have_f) { 1199 *p++ = '/'; 1200 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1201 IPV6_FLOWINFO_MASK), spec); 1202 } 1203 if (have_s) { 1204 *p++ = '%'; 1205 p = number(p, pend, sa->sin6_scope_id, spec); 1206 } 1207 *p = '\0'; 1208 1209 return string(buf, end, ip6_addr, spec); 1210 } 1211 1212 static noinline_for_stack 1213 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1214 struct printf_spec spec, const char *fmt) 1215 { 1216 bool have_p = false; 1217 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1218 char *pend = ip4_addr + sizeof(ip4_addr); 1219 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1220 char fmt4[3] = { fmt[0], '4', 0 }; 1221 1222 fmt++; 1223 while (isalpha(*++fmt)) { 1224 switch (*fmt) { 1225 case 'p': 1226 have_p = true; 1227 break; 1228 case 'h': 1229 case 'l': 1230 case 'n': 1231 case 'b': 1232 fmt4[2] = *fmt; 1233 break; 1234 } 1235 } 1236 1237 p = ip4_string(ip4_addr, addr, fmt4); 1238 if (have_p) { 1239 *p++ = ':'; 1240 p = number(p, pend, ntohs(sa->sin_port), spec); 1241 } 1242 *p = '\0'; 1243 1244 return string(buf, end, ip4_addr, spec); 1245 } 1246 1247 static noinline_for_stack 1248 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1249 const char *fmt) 1250 { 1251 bool found = true; 1252 int count = 1; 1253 unsigned int flags = 0; 1254 int len; 1255 1256 if (spec.field_width == 0) 1257 return buf; /* nothing to print */ 1258 1259 if (ZERO_OR_NULL_PTR(addr)) 1260 return string(buf, end, NULL, spec); /* NULL pointer */ 1261 1262 1263 do { 1264 switch (fmt[count++]) { 1265 case 'a': 1266 flags |= ESCAPE_ANY; 1267 break; 1268 case 'c': 1269 flags |= ESCAPE_SPECIAL; 1270 break; 1271 case 'h': 1272 flags |= ESCAPE_HEX; 1273 break; 1274 case 'n': 1275 flags |= ESCAPE_NULL; 1276 break; 1277 case 'o': 1278 flags |= ESCAPE_OCTAL; 1279 break; 1280 case 'p': 1281 flags |= ESCAPE_NP; 1282 break; 1283 case 's': 1284 flags |= ESCAPE_SPACE; 1285 break; 1286 default: 1287 found = false; 1288 break; 1289 } 1290 } while (found); 1291 1292 if (!flags) 1293 flags = ESCAPE_ANY_NP; 1294 1295 len = spec.field_width < 0 ? 1 : spec.field_width; 1296 1297 /* 1298 * string_escape_mem() writes as many characters as it can to 1299 * the given buffer, and returns the total size of the output 1300 * had the buffer been big enough. 1301 */ 1302 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1303 1304 return buf; 1305 } 1306 1307 static noinline_for_stack 1308 char *uuid_string(char *buf, char *end, const u8 *addr, 1309 struct printf_spec spec, const char *fmt) 1310 { 1311 char uuid[UUID_STRING_LEN + 1]; 1312 char *p = uuid; 1313 int i; 1314 const u8 *index = uuid_index; 1315 bool uc = false; 1316 1317 switch (*(++fmt)) { 1318 case 'L': 1319 uc = true; /* fall-through */ 1320 case 'l': 1321 index = guid_index; 1322 break; 1323 case 'B': 1324 uc = true; 1325 break; 1326 } 1327 1328 for (i = 0; i < 16; i++) { 1329 if (uc) 1330 p = hex_byte_pack_upper(p, addr[index[i]]); 1331 else 1332 p = hex_byte_pack(p, addr[index[i]]); 1333 switch (i) { 1334 case 3: 1335 case 5: 1336 case 7: 1337 case 9: 1338 *p++ = '-'; 1339 break; 1340 } 1341 } 1342 1343 *p = 0; 1344 1345 return string(buf, end, uuid, spec); 1346 } 1347 1348 int kptr_restrict __read_mostly; 1349 1350 static noinline_for_stack 1351 char *restricted_pointer(char *buf, char *end, const void *ptr, 1352 struct printf_spec spec) 1353 { 1354 spec.base = 16; 1355 spec.flags |= SMALL; 1356 if (spec.field_width == -1) { 1357 spec.field_width = 2 * sizeof(ptr); 1358 spec.flags |= ZEROPAD; 1359 } 1360 1361 switch (kptr_restrict) { 1362 case 0: 1363 /* Always print %pK values */ 1364 break; 1365 case 1: { 1366 const struct cred *cred; 1367 1368 /* 1369 * kptr_restrict==1 cannot be used in IRQ context 1370 * because its test for CAP_SYSLOG would be meaningless. 1371 */ 1372 if (in_irq() || in_serving_softirq() || in_nmi()) 1373 return string(buf, end, "pK-error", spec); 1374 1375 /* 1376 * Only print the real pointer value if the current 1377 * process has CAP_SYSLOG and is running with the 1378 * same credentials it started with. This is because 1379 * access to files is checked at open() time, but %pK 1380 * checks permission at read() time. We don't want to 1381 * leak pointer values if a binary opens a file using 1382 * %pK and then elevates privileges before reading it. 1383 */ 1384 cred = current_cred(); 1385 if (!has_capability_noaudit(current, CAP_SYSLOG) || 1386 !uid_eq(cred->euid, cred->uid) || 1387 !gid_eq(cred->egid, cred->gid)) 1388 ptr = NULL; 1389 break; 1390 } 1391 case 2: 1392 default: 1393 /* Always print 0's for %pK */ 1394 ptr = NULL; 1395 break; 1396 } 1397 1398 return number(buf, end, (unsigned long)ptr, spec); 1399 } 1400 1401 static noinline_for_stack 1402 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt) 1403 { 1404 unsigned long long num; 1405 int size; 1406 1407 switch (fmt[1]) { 1408 case 'F': 1409 num = *(const netdev_features_t *)addr; 1410 size = sizeof(netdev_features_t); 1411 break; 1412 default: 1413 num = (unsigned long)addr; 1414 size = sizeof(unsigned long); 1415 break; 1416 } 1417 1418 return special_hex_number(buf, end, num, size); 1419 } 1420 1421 static noinline_for_stack 1422 char *address_val(char *buf, char *end, const void *addr, const char *fmt) 1423 { 1424 unsigned long long num; 1425 int size; 1426 1427 switch (fmt[1]) { 1428 case 'd': 1429 num = *(const dma_addr_t *)addr; 1430 size = sizeof(dma_addr_t); 1431 break; 1432 case 'p': 1433 default: 1434 num = *(const phys_addr_t *)addr; 1435 size = sizeof(phys_addr_t); 1436 break; 1437 } 1438 1439 return special_hex_number(buf, end, num, size); 1440 } 1441 1442 static noinline_for_stack 1443 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1444 const char *fmt) 1445 { 1446 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk) 1447 return string(buf, end, NULL, spec); 1448 1449 switch (fmt[1]) { 1450 case 'r': 1451 return number(buf, end, clk_get_rate(clk), spec); 1452 1453 case 'n': 1454 default: 1455 #ifdef CONFIG_COMMON_CLK 1456 return string(buf, end, __clk_get_name(clk), spec); 1457 #else 1458 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long)); 1459 #endif 1460 } 1461 } 1462 1463 static 1464 char *format_flags(char *buf, char *end, unsigned long flags, 1465 const struct trace_print_flags *names) 1466 { 1467 unsigned long mask; 1468 const struct printf_spec strspec = { 1469 .field_width = -1, 1470 .precision = -1, 1471 }; 1472 const struct printf_spec numspec = { 1473 .flags = SPECIAL|SMALL, 1474 .field_width = -1, 1475 .precision = -1, 1476 .base = 16, 1477 }; 1478 1479 for ( ; flags && names->name; names++) { 1480 mask = names->mask; 1481 if ((flags & mask) != mask) 1482 continue; 1483 1484 buf = string(buf, end, names->name, strspec); 1485 1486 flags &= ~mask; 1487 if (flags) { 1488 if (buf < end) 1489 *buf = '|'; 1490 buf++; 1491 } 1492 } 1493 1494 if (flags) 1495 buf = number(buf, end, flags, numspec); 1496 1497 return buf; 1498 } 1499 1500 static noinline_for_stack 1501 char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt) 1502 { 1503 unsigned long flags; 1504 const struct trace_print_flags *names; 1505 1506 switch (fmt[1]) { 1507 case 'p': 1508 flags = *(unsigned long *)flags_ptr; 1509 /* Remove zone id */ 1510 flags &= (1UL << NR_PAGEFLAGS) - 1; 1511 names = pageflag_names; 1512 break; 1513 case 'v': 1514 flags = *(unsigned long *)flags_ptr; 1515 names = vmaflag_names; 1516 break; 1517 case 'g': 1518 flags = *(gfp_t *)flags_ptr; 1519 names = gfpflag_names; 1520 break; 1521 default: 1522 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]); 1523 return buf; 1524 } 1525 1526 return format_flags(buf, end, flags, names); 1527 } 1528 1529 static const char *device_node_name_for_depth(const struct device_node *np, int depth) 1530 { 1531 for ( ; np && depth; depth--) 1532 np = np->parent; 1533 1534 return kbasename(np->full_name); 1535 } 1536 1537 static noinline_for_stack 1538 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end) 1539 { 1540 int depth; 1541 const struct device_node *parent = np->parent; 1542 static const struct printf_spec strspec = { 1543 .field_width = -1, 1544 .precision = -1, 1545 }; 1546 1547 /* special case for root node */ 1548 if (!parent) 1549 return string(buf, end, "/", strspec); 1550 1551 for (depth = 0; parent->parent; depth++) 1552 parent = parent->parent; 1553 1554 for ( ; depth >= 0; depth--) { 1555 buf = string(buf, end, "/", strspec); 1556 buf = string(buf, end, device_node_name_for_depth(np, depth), 1557 strspec); 1558 } 1559 return buf; 1560 } 1561 1562 static noinline_for_stack 1563 char *device_node_string(char *buf, char *end, struct device_node *dn, 1564 struct printf_spec spec, const char *fmt) 1565 { 1566 char tbuf[sizeof("xxxx") + 1]; 1567 const char *p; 1568 int ret; 1569 char *buf_start = buf; 1570 struct property *prop; 1571 bool has_mult, pass; 1572 static const struct printf_spec num_spec = { 1573 .flags = SMALL, 1574 .field_width = -1, 1575 .precision = -1, 1576 .base = 10, 1577 }; 1578 1579 struct printf_spec str_spec = spec; 1580 str_spec.field_width = -1; 1581 1582 if (!IS_ENABLED(CONFIG_OF)) 1583 return string(buf, end, "(!OF)", spec); 1584 1585 if ((unsigned long)dn < PAGE_SIZE) 1586 return string(buf, end, "(null)", spec); 1587 1588 /* simple case without anything any more format specifiers */ 1589 fmt++; 1590 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 1591 fmt = "f"; 1592 1593 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 1594 if (pass) { 1595 if (buf < end) 1596 *buf = ':'; 1597 buf++; 1598 } 1599 1600 switch (*fmt) { 1601 case 'f': /* full_name */ 1602 buf = device_node_gen_full_name(dn, buf, end); 1603 break; 1604 case 'n': /* name */ 1605 buf = string(buf, end, dn->name, str_spec); 1606 break; 1607 case 'p': /* phandle */ 1608 buf = number(buf, end, (unsigned int)dn->phandle, num_spec); 1609 break; 1610 case 'P': /* path-spec */ 1611 p = kbasename(of_node_full_name(dn)); 1612 if (!p[1]) 1613 p = "/"; 1614 buf = string(buf, end, p, str_spec); 1615 break; 1616 case 'F': /* flags */ 1617 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 1618 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 1619 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 1620 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 1621 tbuf[4] = 0; 1622 buf = string(buf, end, tbuf, str_spec); 1623 break; 1624 case 'c': /* major compatible string */ 1625 ret = of_property_read_string(dn, "compatible", &p); 1626 if (!ret) 1627 buf = string(buf, end, p, str_spec); 1628 break; 1629 case 'C': /* full compatible string */ 1630 has_mult = false; 1631 of_property_for_each_string(dn, "compatible", prop, p) { 1632 if (has_mult) 1633 buf = string(buf, end, ",", str_spec); 1634 buf = string(buf, end, "\"", str_spec); 1635 buf = string(buf, end, p, str_spec); 1636 buf = string(buf, end, "\"", str_spec); 1637 1638 has_mult = true; 1639 } 1640 break; 1641 default: 1642 break; 1643 } 1644 } 1645 1646 return widen_string(buf, buf - buf_start, end, spec); 1647 } 1648 1649 static noinline_for_stack 1650 char *pointer_string(char *buf, char *end, const void *ptr, 1651 struct printf_spec spec) 1652 { 1653 spec.base = 16; 1654 spec.flags |= SMALL; 1655 if (spec.field_width == -1) { 1656 spec.field_width = 2 * sizeof(ptr); 1657 spec.flags |= ZEROPAD; 1658 } 1659 1660 return number(buf, end, (unsigned long int)ptr, spec); 1661 } 1662 1663 static bool have_filled_random_ptr_key __read_mostly; 1664 static siphash_key_t ptr_key __read_mostly; 1665 1666 static void fill_random_ptr_key(struct random_ready_callback *unused) 1667 { 1668 get_random_bytes(&ptr_key, sizeof(ptr_key)); 1669 /* 1670 * have_filled_random_ptr_key==true is dependent on get_random_bytes(). 1671 * ptr_to_id() needs to see have_filled_random_ptr_key==true 1672 * after get_random_bytes() returns. 1673 */ 1674 smp_mb(); 1675 WRITE_ONCE(have_filled_random_ptr_key, true); 1676 } 1677 1678 static struct random_ready_callback random_ready = { 1679 .func = fill_random_ptr_key 1680 }; 1681 1682 static int __init initialize_ptr_random(void) 1683 { 1684 int ret = add_random_ready_callback(&random_ready); 1685 1686 if (!ret) { 1687 return 0; 1688 } else if (ret == -EALREADY) { 1689 fill_random_ptr_key(&random_ready); 1690 return 0; 1691 } 1692 1693 return ret; 1694 } 1695 early_initcall(initialize_ptr_random); 1696 1697 /* Maps a pointer to a 32 bit unique identifier. */ 1698 static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec) 1699 { 1700 unsigned long hashval; 1701 const int default_width = 2 * sizeof(ptr); 1702 1703 if (unlikely(!have_filled_random_ptr_key)) { 1704 spec.field_width = default_width; 1705 /* string length must be less than default_width */ 1706 return string(buf, end, "(ptrval)", spec); 1707 } 1708 1709 #ifdef CONFIG_64BIT 1710 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 1711 /* 1712 * Mask off the first 32 bits, this makes explicit that we have 1713 * modified the address (and 32 bits is plenty for a unique ID). 1714 */ 1715 hashval = hashval & 0xffffffff; 1716 #else 1717 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 1718 #endif 1719 1720 spec.flags |= SMALL; 1721 if (spec.field_width == -1) { 1722 spec.field_width = default_width; 1723 spec.flags |= ZEROPAD; 1724 } 1725 spec.base = 16; 1726 1727 return number(buf, end, hashval, spec); 1728 } 1729 1730 /* 1731 * Show a '%p' thing. A kernel extension is that the '%p' is followed 1732 * by an extra set of alphanumeric characters that are extended format 1733 * specifiers. 1734 * 1735 * Please update scripts/checkpatch.pl when adding/removing conversion 1736 * characters. (Search for "check for vsprintf extension"). 1737 * 1738 * Right now we handle: 1739 * 1740 * - 'F' For symbolic function descriptor pointers with offset 1741 * - 'f' For simple symbolic function names without offset 1742 * - 'S' For symbolic direct pointers with offset 1743 * - 's' For symbolic direct pointers without offset 1744 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation 1745 * - 'B' For backtraced symbolic direct pointers with offset 1746 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 1747 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 1748 * - 'b[l]' For a bitmap, the number of bits is determined by the field 1749 * width which must be explicitly specified either as part of the 1750 * format string '%32b[l]' or through '%*b[l]', [l] selects 1751 * range-list format instead of hex format 1752 * - 'M' For a 6-byte MAC address, it prints the address in the 1753 * usual colon-separated hex notation 1754 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 1755 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 1756 * with a dash-separated hex notation 1757 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 1758 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 1759 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 1760 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 1761 * [S][pfs] 1762 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 1763 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 1764 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 1765 * IPv6 omits the colons (01020304...0f) 1766 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 1767 * [S][pfs] 1768 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 1769 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 1770 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 1771 * - 'I[6S]c' for IPv6 addresses printed as specified by 1772 * http://tools.ietf.org/html/rfc5952 1773 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 1774 * of the following flags (see string_escape_mem() for the 1775 * details): 1776 * a - ESCAPE_ANY 1777 * c - ESCAPE_SPECIAL 1778 * h - ESCAPE_HEX 1779 * n - ESCAPE_NULL 1780 * o - ESCAPE_OCTAL 1781 * p - ESCAPE_NP 1782 * s - ESCAPE_SPACE 1783 * By default ESCAPE_ANY_NP is used. 1784 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 1785 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 1786 * Options for %pU are: 1787 * b big endian lower case hex (default) 1788 * B big endian UPPER case hex 1789 * l little endian lower case hex 1790 * L little endian UPPER case hex 1791 * big endian output byte order is: 1792 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 1793 * little endian output byte order is: 1794 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 1795 * - 'V' For a struct va_format which contains a format string * and va_list *, 1796 * call vsnprintf(->format, *->va_list). 1797 * Implements a "recursive vsnprintf". 1798 * Do not use this feature without some mechanism to verify the 1799 * correctness of the format string and va_list arguments. 1800 * - 'K' For a kernel pointer that should be hidden from unprivileged users 1801 * - 'NF' For a netdev_features_t 1802 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 1803 * a certain separator (' ' by default): 1804 * C colon 1805 * D dash 1806 * N no separator 1807 * The maximum supported length is 64 bytes of the input. Consider 1808 * to use print_hex_dump() for the larger input. 1809 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 1810 * (default assumed to be phys_addr_t, passed by reference) 1811 * - 'd[234]' For a dentry name (optionally 2-4 last components) 1812 * - 'D[234]' Same as 'd' but for a struct file 1813 * - 'g' For block_device name (gendisk + partition number) 1814 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 1815 * (legacy clock framework) of the clock 1816 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 1817 * (legacy clock framework) of the clock 1818 * - 'Cr' For a clock, it prints the current rate of the clock 1819 * - 'G' For flags to be printed as a collection of symbolic strings that would 1820 * construct the specific value. Supported flags given by option: 1821 * p page flags (see struct page) given as pointer to unsigned long 1822 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 1823 * v vma flags (VM_*) given as pointer to unsigned long 1824 * - 'O' For a kobject based struct. Must be one of the following: 1825 * - 'OF[fnpPcCF]' For a device tree object 1826 * Without any optional arguments prints the full_name 1827 * f device node full_name 1828 * n device node name 1829 * p device node phandle 1830 * P device node path spec (name + @unit) 1831 * F device node flags 1832 * c major compatible string 1833 * C full compatible string 1834 * 1835 * - 'x' For printing the address. Equivalent to "%lx". 1836 * 1837 * ** When making changes please also update: 1838 * Documentation/core-api/printk-formats.rst 1839 * 1840 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 1841 * function pointers are really function descriptors, which contain a 1842 * pointer to the real address. 1843 * 1844 * Note: The default behaviour (unadorned %p) is to hash the address, 1845 * rendering it useful as a unique identifier. 1846 */ 1847 static noinline_for_stack 1848 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 1849 struct printf_spec spec) 1850 { 1851 const int default_width = 2 * sizeof(void *); 1852 1853 if (!ptr && *fmt != 'K') { 1854 /* 1855 * Print (null) with the same width as a pointer so it makes 1856 * tabular output look nice. 1857 */ 1858 if (spec.field_width == -1) 1859 spec.field_width = default_width; 1860 return string(buf, end, "(null)", spec); 1861 } 1862 1863 switch (*fmt) { 1864 case 'F': 1865 case 'f': 1866 ptr = dereference_function_descriptor(ptr); 1867 /* Fallthrough */ 1868 case 'S': 1869 case 's': 1870 case 'B': 1871 return symbol_string(buf, end, ptr, spec, fmt); 1872 case 'R': 1873 case 'r': 1874 return resource_string(buf, end, ptr, spec, fmt); 1875 case 'h': 1876 return hex_string(buf, end, ptr, spec, fmt); 1877 case 'b': 1878 switch (fmt[1]) { 1879 case 'l': 1880 return bitmap_list_string(buf, end, ptr, spec, fmt); 1881 default: 1882 return bitmap_string(buf, end, ptr, spec, fmt); 1883 } 1884 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 1885 case 'm': /* Contiguous: 000102030405 */ 1886 /* [mM]F (FDDI) */ 1887 /* [mM]R (Reverse order; Bluetooth) */ 1888 return mac_address_string(buf, end, ptr, spec, fmt); 1889 case 'I': /* Formatted IP supported 1890 * 4: 1.2.3.4 1891 * 6: 0001:0203:...:0708 1892 * 6c: 1::708 or 1::1.2.3.4 1893 */ 1894 case 'i': /* Contiguous: 1895 * 4: 001.002.003.004 1896 * 6: 000102...0f 1897 */ 1898 switch (fmt[1]) { 1899 case '6': 1900 return ip6_addr_string(buf, end, ptr, spec, fmt); 1901 case '4': 1902 return ip4_addr_string(buf, end, ptr, spec, fmt); 1903 case 'S': { 1904 const union { 1905 struct sockaddr raw; 1906 struct sockaddr_in v4; 1907 struct sockaddr_in6 v6; 1908 } *sa = ptr; 1909 1910 switch (sa->raw.sa_family) { 1911 case AF_INET: 1912 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1913 case AF_INET6: 1914 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1915 default: 1916 return string(buf, end, "(invalid address)", spec); 1917 }} 1918 } 1919 break; 1920 case 'E': 1921 return escaped_string(buf, end, ptr, spec, fmt); 1922 case 'U': 1923 return uuid_string(buf, end, ptr, spec, fmt); 1924 case 'V': 1925 { 1926 va_list va; 1927 1928 va_copy(va, *((struct va_format *)ptr)->va); 1929 buf += vsnprintf(buf, end > buf ? end - buf : 0, 1930 ((struct va_format *)ptr)->fmt, va); 1931 va_end(va); 1932 return buf; 1933 } 1934 case 'K': 1935 if (!kptr_restrict) 1936 break; 1937 return restricted_pointer(buf, end, ptr, spec); 1938 case 'N': 1939 return netdev_bits(buf, end, ptr, fmt); 1940 case 'a': 1941 return address_val(buf, end, ptr, fmt); 1942 case 'd': 1943 return dentry_name(buf, end, ptr, spec, fmt); 1944 case 'C': 1945 return clock(buf, end, ptr, spec, fmt); 1946 case 'D': 1947 return dentry_name(buf, end, 1948 ((const struct file *)ptr)->f_path.dentry, 1949 spec, fmt); 1950 #ifdef CONFIG_BLOCK 1951 case 'g': 1952 return bdev_name(buf, end, ptr, spec, fmt); 1953 #endif 1954 1955 case 'G': 1956 return flags_string(buf, end, ptr, fmt); 1957 case 'O': 1958 switch (fmt[1]) { 1959 case 'F': 1960 return device_node_string(buf, end, ptr, spec, fmt + 1); 1961 } 1962 case 'x': 1963 return pointer_string(buf, end, ptr, spec); 1964 } 1965 1966 /* default is to _not_ leak addresses, hash before printing */ 1967 return ptr_to_id(buf, end, ptr, spec); 1968 } 1969 1970 /* 1971 * Helper function to decode printf style format. 1972 * Each call decode a token from the format and return the 1973 * number of characters read (or likely the delta where it wants 1974 * to go on the next call). 1975 * The decoded token is returned through the parameters 1976 * 1977 * 'h', 'l', or 'L' for integer fields 1978 * 'z' support added 23/7/1999 S.H. 1979 * 'z' changed to 'Z' --davidm 1/25/99 1980 * 'Z' changed to 'z' --adobriyan 2017-01-25 1981 * 't' added for ptrdiff_t 1982 * 1983 * @fmt: the format string 1984 * @type of the token returned 1985 * @flags: various flags such as +, -, # tokens.. 1986 * @field_width: overwritten width 1987 * @base: base of the number (octal, hex, ...) 1988 * @precision: precision of a number 1989 * @qualifier: qualifier of a number (long, size_t, ...) 1990 */ 1991 static noinline_for_stack 1992 int format_decode(const char *fmt, struct printf_spec *spec) 1993 { 1994 const char *start = fmt; 1995 char qualifier; 1996 1997 /* we finished early by reading the field width */ 1998 if (spec->type == FORMAT_TYPE_WIDTH) { 1999 if (spec->field_width < 0) { 2000 spec->field_width = -spec->field_width; 2001 spec->flags |= LEFT; 2002 } 2003 spec->type = FORMAT_TYPE_NONE; 2004 goto precision; 2005 } 2006 2007 /* we finished early by reading the precision */ 2008 if (spec->type == FORMAT_TYPE_PRECISION) { 2009 if (spec->precision < 0) 2010 spec->precision = 0; 2011 2012 spec->type = FORMAT_TYPE_NONE; 2013 goto qualifier; 2014 } 2015 2016 /* By default */ 2017 spec->type = FORMAT_TYPE_NONE; 2018 2019 for (; *fmt ; ++fmt) { 2020 if (*fmt == '%') 2021 break; 2022 } 2023 2024 /* Return the current non-format string */ 2025 if (fmt != start || !*fmt) 2026 return fmt - start; 2027 2028 /* Process flags */ 2029 spec->flags = 0; 2030 2031 while (1) { /* this also skips first '%' */ 2032 bool found = true; 2033 2034 ++fmt; 2035 2036 switch (*fmt) { 2037 case '-': spec->flags |= LEFT; break; 2038 case '+': spec->flags |= PLUS; break; 2039 case ' ': spec->flags |= SPACE; break; 2040 case '#': spec->flags |= SPECIAL; break; 2041 case '0': spec->flags |= ZEROPAD; break; 2042 default: found = false; 2043 } 2044 2045 if (!found) 2046 break; 2047 } 2048 2049 /* get field width */ 2050 spec->field_width = -1; 2051 2052 if (isdigit(*fmt)) 2053 spec->field_width = skip_atoi(&fmt); 2054 else if (*fmt == '*') { 2055 /* it's the next argument */ 2056 spec->type = FORMAT_TYPE_WIDTH; 2057 return ++fmt - start; 2058 } 2059 2060 precision: 2061 /* get the precision */ 2062 spec->precision = -1; 2063 if (*fmt == '.') { 2064 ++fmt; 2065 if (isdigit(*fmt)) { 2066 spec->precision = skip_atoi(&fmt); 2067 if (spec->precision < 0) 2068 spec->precision = 0; 2069 } else if (*fmt == '*') { 2070 /* it's the next argument */ 2071 spec->type = FORMAT_TYPE_PRECISION; 2072 return ++fmt - start; 2073 } 2074 } 2075 2076 qualifier: 2077 /* get the conversion qualifier */ 2078 qualifier = 0; 2079 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2080 *fmt == 'z' || *fmt == 't') { 2081 qualifier = *fmt++; 2082 if (unlikely(qualifier == *fmt)) { 2083 if (qualifier == 'l') { 2084 qualifier = 'L'; 2085 ++fmt; 2086 } else if (qualifier == 'h') { 2087 qualifier = 'H'; 2088 ++fmt; 2089 } 2090 } 2091 } 2092 2093 /* default base */ 2094 spec->base = 10; 2095 switch (*fmt) { 2096 case 'c': 2097 spec->type = FORMAT_TYPE_CHAR; 2098 return ++fmt - start; 2099 2100 case 's': 2101 spec->type = FORMAT_TYPE_STR; 2102 return ++fmt - start; 2103 2104 case 'p': 2105 spec->type = FORMAT_TYPE_PTR; 2106 return ++fmt - start; 2107 2108 case '%': 2109 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2110 return ++fmt - start; 2111 2112 /* integer number formats - set up the flags and "break" */ 2113 case 'o': 2114 spec->base = 8; 2115 break; 2116 2117 case 'x': 2118 spec->flags |= SMALL; 2119 2120 case 'X': 2121 spec->base = 16; 2122 break; 2123 2124 case 'd': 2125 case 'i': 2126 spec->flags |= SIGN; 2127 case 'u': 2128 break; 2129 2130 case 'n': 2131 /* 2132 * Since %n poses a greater security risk than 2133 * utility, treat it as any other invalid or 2134 * unsupported format specifier. 2135 */ 2136 /* Fall-through */ 2137 2138 default: 2139 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2140 spec->type = FORMAT_TYPE_INVALID; 2141 return fmt - start; 2142 } 2143 2144 if (qualifier == 'L') 2145 spec->type = FORMAT_TYPE_LONG_LONG; 2146 else if (qualifier == 'l') { 2147 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2148 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2149 } else if (qualifier == 'z') { 2150 spec->type = FORMAT_TYPE_SIZE_T; 2151 } else if (qualifier == 't') { 2152 spec->type = FORMAT_TYPE_PTRDIFF; 2153 } else if (qualifier == 'H') { 2154 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2155 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2156 } else if (qualifier == 'h') { 2157 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2158 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2159 } else { 2160 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2161 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2162 } 2163 2164 return ++fmt - start; 2165 } 2166 2167 static void 2168 set_field_width(struct printf_spec *spec, int width) 2169 { 2170 spec->field_width = width; 2171 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2172 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2173 } 2174 } 2175 2176 static void 2177 set_precision(struct printf_spec *spec, int prec) 2178 { 2179 spec->precision = prec; 2180 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2181 spec->precision = clamp(prec, 0, PRECISION_MAX); 2182 } 2183 } 2184 2185 /** 2186 * vsnprintf - Format a string and place it in a buffer 2187 * @buf: The buffer to place the result into 2188 * @size: The size of the buffer, including the trailing null space 2189 * @fmt: The format string to use 2190 * @args: Arguments for the format string 2191 * 2192 * This function generally follows C99 vsnprintf, but has some 2193 * extensions and a few limitations: 2194 * 2195 * - ``%n`` is unsupported 2196 * - ``%p*`` is handled by pointer() 2197 * 2198 * See pointer() or Documentation/core-api/printk-formats.rst for more 2199 * extensive description. 2200 * 2201 * **Please update the documentation in both places when making changes** 2202 * 2203 * The return value is the number of characters which would 2204 * be generated for the given input, excluding the trailing 2205 * '\0', as per ISO C99. If you want to have the exact 2206 * number of characters written into @buf as return value 2207 * (not including the trailing '\0'), use vscnprintf(). If the 2208 * return is greater than or equal to @size, the resulting 2209 * string is truncated. 2210 * 2211 * If you're not already dealing with a va_list consider using snprintf(). 2212 */ 2213 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2214 { 2215 unsigned long long num; 2216 char *str, *end; 2217 struct printf_spec spec = {0}; 2218 2219 /* Reject out-of-range values early. Large positive sizes are 2220 used for unknown buffer sizes. */ 2221 if (WARN_ON_ONCE(size > INT_MAX)) 2222 return 0; 2223 2224 str = buf; 2225 end = buf + size; 2226 2227 /* Make sure end is always >= buf */ 2228 if (end < buf) { 2229 end = ((void *)-1); 2230 size = end - buf; 2231 } 2232 2233 while (*fmt) { 2234 const char *old_fmt = fmt; 2235 int read = format_decode(fmt, &spec); 2236 2237 fmt += read; 2238 2239 switch (spec.type) { 2240 case FORMAT_TYPE_NONE: { 2241 int copy = read; 2242 if (str < end) { 2243 if (copy > end - str) 2244 copy = end - str; 2245 memcpy(str, old_fmt, copy); 2246 } 2247 str += read; 2248 break; 2249 } 2250 2251 case FORMAT_TYPE_WIDTH: 2252 set_field_width(&spec, va_arg(args, int)); 2253 break; 2254 2255 case FORMAT_TYPE_PRECISION: 2256 set_precision(&spec, va_arg(args, int)); 2257 break; 2258 2259 case FORMAT_TYPE_CHAR: { 2260 char c; 2261 2262 if (!(spec.flags & LEFT)) { 2263 while (--spec.field_width > 0) { 2264 if (str < end) 2265 *str = ' '; 2266 ++str; 2267 2268 } 2269 } 2270 c = (unsigned char) va_arg(args, int); 2271 if (str < end) 2272 *str = c; 2273 ++str; 2274 while (--spec.field_width > 0) { 2275 if (str < end) 2276 *str = ' '; 2277 ++str; 2278 } 2279 break; 2280 } 2281 2282 case FORMAT_TYPE_STR: 2283 str = string(str, end, va_arg(args, char *), spec); 2284 break; 2285 2286 case FORMAT_TYPE_PTR: 2287 str = pointer(fmt, str, end, va_arg(args, void *), 2288 spec); 2289 while (isalnum(*fmt)) 2290 fmt++; 2291 break; 2292 2293 case FORMAT_TYPE_PERCENT_CHAR: 2294 if (str < end) 2295 *str = '%'; 2296 ++str; 2297 break; 2298 2299 case FORMAT_TYPE_INVALID: 2300 /* 2301 * Presumably the arguments passed gcc's type 2302 * checking, but there is no safe or sane way 2303 * for us to continue parsing the format and 2304 * fetching from the va_list; the remaining 2305 * specifiers and arguments would be out of 2306 * sync. 2307 */ 2308 goto out; 2309 2310 default: 2311 switch (spec.type) { 2312 case FORMAT_TYPE_LONG_LONG: 2313 num = va_arg(args, long long); 2314 break; 2315 case FORMAT_TYPE_ULONG: 2316 num = va_arg(args, unsigned long); 2317 break; 2318 case FORMAT_TYPE_LONG: 2319 num = va_arg(args, long); 2320 break; 2321 case FORMAT_TYPE_SIZE_T: 2322 if (spec.flags & SIGN) 2323 num = va_arg(args, ssize_t); 2324 else 2325 num = va_arg(args, size_t); 2326 break; 2327 case FORMAT_TYPE_PTRDIFF: 2328 num = va_arg(args, ptrdiff_t); 2329 break; 2330 case FORMAT_TYPE_UBYTE: 2331 num = (unsigned char) va_arg(args, int); 2332 break; 2333 case FORMAT_TYPE_BYTE: 2334 num = (signed char) va_arg(args, int); 2335 break; 2336 case FORMAT_TYPE_USHORT: 2337 num = (unsigned short) va_arg(args, int); 2338 break; 2339 case FORMAT_TYPE_SHORT: 2340 num = (short) va_arg(args, int); 2341 break; 2342 case FORMAT_TYPE_INT: 2343 num = (int) va_arg(args, int); 2344 break; 2345 default: 2346 num = va_arg(args, unsigned int); 2347 } 2348 2349 str = number(str, end, num, spec); 2350 } 2351 } 2352 2353 out: 2354 if (size > 0) { 2355 if (str < end) 2356 *str = '\0'; 2357 else 2358 end[-1] = '\0'; 2359 } 2360 2361 /* the trailing null byte doesn't count towards the total */ 2362 return str-buf; 2363 2364 } 2365 EXPORT_SYMBOL(vsnprintf); 2366 2367 /** 2368 * vscnprintf - Format a string and place it in a buffer 2369 * @buf: The buffer to place the result into 2370 * @size: The size of the buffer, including the trailing null space 2371 * @fmt: The format string to use 2372 * @args: Arguments for the format string 2373 * 2374 * The return value is the number of characters which have been written into 2375 * the @buf not including the trailing '\0'. If @size is == 0 the function 2376 * returns 0. 2377 * 2378 * If you're not already dealing with a va_list consider using scnprintf(). 2379 * 2380 * See the vsnprintf() documentation for format string extensions over C99. 2381 */ 2382 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2383 { 2384 int i; 2385 2386 i = vsnprintf(buf, size, fmt, args); 2387 2388 if (likely(i < size)) 2389 return i; 2390 if (size != 0) 2391 return size - 1; 2392 return 0; 2393 } 2394 EXPORT_SYMBOL(vscnprintf); 2395 2396 /** 2397 * snprintf - Format a string and place it in a buffer 2398 * @buf: The buffer to place the result into 2399 * @size: The size of the buffer, including the trailing null space 2400 * @fmt: The format string to use 2401 * @...: Arguments for the format string 2402 * 2403 * The return value is the number of characters which would be 2404 * generated for the given input, excluding the trailing null, 2405 * as per ISO C99. If the return is greater than or equal to 2406 * @size, the resulting string is truncated. 2407 * 2408 * See the vsnprintf() documentation for format string extensions over C99. 2409 */ 2410 int snprintf(char *buf, size_t size, const char *fmt, ...) 2411 { 2412 va_list args; 2413 int i; 2414 2415 va_start(args, fmt); 2416 i = vsnprintf(buf, size, fmt, args); 2417 va_end(args); 2418 2419 return i; 2420 } 2421 EXPORT_SYMBOL(snprintf); 2422 2423 /** 2424 * scnprintf - Format a string and place it in a buffer 2425 * @buf: The buffer to place the result into 2426 * @size: The size of the buffer, including the trailing null space 2427 * @fmt: The format string to use 2428 * @...: Arguments for the format string 2429 * 2430 * The return value is the number of characters written into @buf not including 2431 * the trailing '\0'. If @size is == 0 the function returns 0. 2432 */ 2433 2434 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2435 { 2436 va_list args; 2437 int i; 2438 2439 va_start(args, fmt); 2440 i = vscnprintf(buf, size, fmt, args); 2441 va_end(args); 2442 2443 return i; 2444 } 2445 EXPORT_SYMBOL(scnprintf); 2446 2447 /** 2448 * vsprintf - Format a string and place it in a buffer 2449 * @buf: The buffer to place the result into 2450 * @fmt: The format string to use 2451 * @args: Arguments for the format string 2452 * 2453 * The function returns the number of characters written 2454 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2455 * buffer overflows. 2456 * 2457 * If you're not already dealing with a va_list consider using sprintf(). 2458 * 2459 * See the vsnprintf() documentation for format string extensions over C99. 2460 */ 2461 int vsprintf(char *buf, const char *fmt, va_list args) 2462 { 2463 return vsnprintf(buf, INT_MAX, fmt, args); 2464 } 2465 EXPORT_SYMBOL(vsprintf); 2466 2467 /** 2468 * sprintf - Format a string and place it in a buffer 2469 * @buf: The buffer to place the result into 2470 * @fmt: The format string to use 2471 * @...: Arguments for the format string 2472 * 2473 * The function returns the number of characters written 2474 * into @buf. Use snprintf() or scnprintf() in order to avoid 2475 * buffer overflows. 2476 * 2477 * See the vsnprintf() documentation for format string extensions over C99. 2478 */ 2479 int sprintf(char *buf, const char *fmt, ...) 2480 { 2481 va_list args; 2482 int i; 2483 2484 va_start(args, fmt); 2485 i = vsnprintf(buf, INT_MAX, fmt, args); 2486 va_end(args); 2487 2488 return i; 2489 } 2490 EXPORT_SYMBOL(sprintf); 2491 2492 #ifdef CONFIG_BINARY_PRINTF 2493 /* 2494 * bprintf service: 2495 * vbin_printf() - VA arguments to binary data 2496 * bstr_printf() - Binary data to text string 2497 */ 2498 2499 /** 2500 * vbin_printf - Parse a format string and place args' binary value in a buffer 2501 * @bin_buf: The buffer to place args' binary value 2502 * @size: The size of the buffer(by words(32bits), not characters) 2503 * @fmt: The format string to use 2504 * @args: Arguments for the format string 2505 * 2506 * The format follows C99 vsnprintf, except %n is ignored, and its argument 2507 * is skipped. 2508 * 2509 * The return value is the number of words(32bits) which would be generated for 2510 * the given input. 2511 * 2512 * NOTE: 2513 * If the return value is greater than @size, the resulting bin_buf is NOT 2514 * valid for bstr_printf(). 2515 */ 2516 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 2517 { 2518 struct printf_spec spec = {0}; 2519 char *str, *end; 2520 2521 str = (char *)bin_buf; 2522 end = (char *)(bin_buf + size); 2523 2524 #define save_arg(type) \ 2525 do { \ 2526 if (sizeof(type) == 8) { \ 2527 unsigned long long value; \ 2528 str = PTR_ALIGN(str, sizeof(u32)); \ 2529 value = va_arg(args, unsigned long long); \ 2530 if (str + sizeof(type) <= end) { \ 2531 *(u32 *)str = *(u32 *)&value; \ 2532 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 2533 } \ 2534 } else { \ 2535 unsigned long value; \ 2536 str = PTR_ALIGN(str, sizeof(type)); \ 2537 value = va_arg(args, int); \ 2538 if (str + sizeof(type) <= end) \ 2539 *(typeof(type) *)str = (type)value; \ 2540 } \ 2541 str += sizeof(type); \ 2542 } while (0) 2543 2544 while (*fmt) { 2545 int read = format_decode(fmt, &spec); 2546 2547 fmt += read; 2548 2549 switch (spec.type) { 2550 case FORMAT_TYPE_NONE: 2551 case FORMAT_TYPE_PERCENT_CHAR: 2552 break; 2553 case FORMAT_TYPE_INVALID: 2554 goto out; 2555 2556 case FORMAT_TYPE_WIDTH: 2557 case FORMAT_TYPE_PRECISION: 2558 save_arg(int); 2559 break; 2560 2561 case FORMAT_TYPE_CHAR: 2562 save_arg(char); 2563 break; 2564 2565 case FORMAT_TYPE_STR: { 2566 const char *save_str = va_arg(args, char *); 2567 size_t len; 2568 2569 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 2570 || (unsigned long)save_str < PAGE_SIZE) 2571 save_str = "(null)"; 2572 len = strlen(save_str) + 1; 2573 if (str + len < end) 2574 memcpy(str, save_str, len); 2575 str += len; 2576 break; 2577 } 2578 2579 case FORMAT_TYPE_PTR: 2580 save_arg(void *); 2581 /* skip all alphanumeric pointer suffixes */ 2582 while (isalnum(*fmt)) 2583 fmt++; 2584 break; 2585 2586 default: 2587 switch (spec.type) { 2588 2589 case FORMAT_TYPE_LONG_LONG: 2590 save_arg(long long); 2591 break; 2592 case FORMAT_TYPE_ULONG: 2593 case FORMAT_TYPE_LONG: 2594 save_arg(unsigned long); 2595 break; 2596 case FORMAT_TYPE_SIZE_T: 2597 save_arg(size_t); 2598 break; 2599 case FORMAT_TYPE_PTRDIFF: 2600 save_arg(ptrdiff_t); 2601 break; 2602 case FORMAT_TYPE_UBYTE: 2603 case FORMAT_TYPE_BYTE: 2604 save_arg(char); 2605 break; 2606 case FORMAT_TYPE_USHORT: 2607 case FORMAT_TYPE_SHORT: 2608 save_arg(short); 2609 break; 2610 default: 2611 save_arg(int); 2612 } 2613 } 2614 } 2615 2616 out: 2617 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 2618 #undef save_arg 2619 } 2620 EXPORT_SYMBOL_GPL(vbin_printf); 2621 2622 /** 2623 * bstr_printf - Format a string from binary arguments and place it in a buffer 2624 * @buf: The buffer to place the result into 2625 * @size: The size of the buffer, including the trailing null space 2626 * @fmt: The format string to use 2627 * @bin_buf: Binary arguments for the format string 2628 * 2629 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 2630 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 2631 * a binary buffer that generated by vbin_printf. 2632 * 2633 * The format follows C99 vsnprintf, but has some extensions: 2634 * see vsnprintf comment for details. 2635 * 2636 * The return value is the number of characters which would 2637 * be generated for the given input, excluding the trailing 2638 * '\0', as per ISO C99. If you want to have the exact 2639 * number of characters written into @buf as return value 2640 * (not including the trailing '\0'), use vscnprintf(). If the 2641 * return is greater than or equal to @size, the resulting 2642 * string is truncated. 2643 */ 2644 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 2645 { 2646 struct printf_spec spec = {0}; 2647 char *str, *end; 2648 const char *args = (const char *)bin_buf; 2649 2650 if (WARN_ON_ONCE(size > INT_MAX)) 2651 return 0; 2652 2653 str = buf; 2654 end = buf + size; 2655 2656 #define get_arg(type) \ 2657 ({ \ 2658 typeof(type) value; \ 2659 if (sizeof(type) == 8) { \ 2660 args = PTR_ALIGN(args, sizeof(u32)); \ 2661 *(u32 *)&value = *(u32 *)args; \ 2662 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 2663 } else { \ 2664 args = PTR_ALIGN(args, sizeof(type)); \ 2665 value = *(typeof(type) *)args; \ 2666 } \ 2667 args += sizeof(type); \ 2668 value; \ 2669 }) 2670 2671 /* Make sure end is always >= buf */ 2672 if (end < buf) { 2673 end = ((void *)-1); 2674 size = end - buf; 2675 } 2676 2677 while (*fmt) { 2678 const char *old_fmt = fmt; 2679 int read = format_decode(fmt, &spec); 2680 2681 fmt += read; 2682 2683 switch (spec.type) { 2684 case FORMAT_TYPE_NONE: { 2685 int copy = read; 2686 if (str < end) { 2687 if (copy > end - str) 2688 copy = end - str; 2689 memcpy(str, old_fmt, copy); 2690 } 2691 str += read; 2692 break; 2693 } 2694 2695 case FORMAT_TYPE_WIDTH: 2696 set_field_width(&spec, get_arg(int)); 2697 break; 2698 2699 case FORMAT_TYPE_PRECISION: 2700 set_precision(&spec, get_arg(int)); 2701 break; 2702 2703 case FORMAT_TYPE_CHAR: { 2704 char c; 2705 2706 if (!(spec.flags & LEFT)) { 2707 while (--spec.field_width > 0) { 2708 if (str < end) 2709 *str = ' '; 2710 ++str; 2711 } 2712 } 2713 c = (unsigned char) get_arg(char); 2714 if (str < end) 2715 *str = c; 2716 ++str; 2717 while (--spec.field_width > 0) { 2718 if (str < end) 2719 *str = ' '; 2720 ++str; 2721 } 2722 break; 2723 } 2724 2725 case FORMAT_TYPE_STR: { 2726 const char *str_arg = args; 2727 args += strlen(str_arg) + 1; 2728 str = string(str, end, (char *)str_arg, spec); 2729 break; 2730 } 2731 2732 case FORMAT_TYPE_PTR: 2733 str = pointer(fmt, str, end, get_arg(void *), spec); 2734 while (isalnum(*fmt)) 2735 fmt++; 2736 break; 2737 2738 case FORMAT_TYPE_PERCENT_CHAR: 2739 if (str < end) 2740 *str = '%'; 2741 ++str; 2742 break; 2743 2744 case FORMAT_TYPE_INVALID: 2745 goto out; 2746 2747 default: { 2748 unsigned long long num; 2749 2750 switch (spec.type) { 2751 2752 case FORMAT_TYPE_LONG_LONG: 2753 num = get_arg(long long); 2754 break; 2755 case FORMAT_TYPE_ULONG: 2756 case FORMAT_TYPE_LONG: 2757 num = get_arg(unsigned long); 2758 break; 2759 case FORMAT_TYPE_SIZE_T: 2760 num = get_arg(size_t); 2761 break; 2762 case FORMAT_TYPE_PTRDIFF: 2763 num = get_arg(ptrdiff_t); 2764 break; 2765 case FORMAT_TYPE_UBYTE: 2766 num = get_arg(unsigned char); 2767 break; 2768 case FORMAT_TYPE_BYTE: 2769 num = get_arg(signed char); 2770 break; 2771 case FORMAT_TYPE_USHORT: 2772 num = get_arg(unsigned short); 2773 break; 2774 case FORMAT_TYPE_SHORT: 2775 num = get_arg(short); 2776 break; 2777 case FORMAT_TYPE_UINT: 2778 num = get_arg(unsigned int); 2779 break; 2780 default: 2781 num = get_arg(int); 2782 } 2783 2784 str = number(str, end, num, spec); 2785 } /* default: */ 2786 } /* switch(spec.type) */ 2787 } /* while(*fmt) */ 2788 2789 out: 2790 if (size > 0) { 2791 if (str < end) 2792 *str = '\0'; 2793 else 2794 end[-1] = '\0'; 2795 } 2796 2797 #undef get_arg 2798 2799 /* the trailing null byte doesn't count towards the total */ 2800 return str - buf; 2801 } 2802 EXPORT_SYMBOL_GPL(bstr_printf); 2803 2804 /** 2805 * bprintf - Parse a format string and place args' binary value in a buffer 2806 * @bin_buf: The buffer to place args' binary value 2807 * @size: The size of the buffer(by words(32bits), not characters) 2808 * @fmt: The format string to use 2809 * @...: Arguments for the format string 2810 * 2811 * The function returns the number of words(u32) written 2812 * into @bin_buf. 2813 */ 2814 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 2815 { 2816 va_list args; 2817 int ret; 2818 2819 va_start(args, fmt); 2820 ret = vbin_printf(bin_buf, size, fmt, args); 2821 va_end(args); 2822 2823 return ret; 2824 } 2825 EXPORT_SYMBOL_GPL(bprintf); 2826 2827 #endif /* CONFIG_BINARY_PRINTF */ 2828 2829 /** 2830 * vsscanf - Unformat a buffer into a list of arguments 2831 * @buf: input buffer 2832 * @fmt: format of buffer 2833 * @args: arguments 2834 */ 2835 int vsscanf(const char *buf, const char *fmt, va_list args) 2836 { 2837 const char *str = buf; 2838 char *next; 2839 char digit; 2840 int num = 0; 2841 u8 qualifier; 2842 unsigned int base; 2843 union { 2844 long long s; 2845 unsigned long long u; 2846 } val; 2847 s16 field_width; 2848 bool is_sign; 2849 2850 while (*fmt) { 2851 /* skip any white space in format */ 2852 /* white space in format matchs any amount of 2853 * white space, including none, in the input. 2854 */ 2855 if (isspace(*fmt)) { 2856 fmt = skip_spaces(++fmt); 2857 str = skip_spaces(str); 2858 } 2859 2860 /* anything that is not a conversion must match exactly */ 2861 if (*fmt != '%' && *fmt) { 2862 if (*fmt++ != *str++) 2863 break; 2864 continue; 2865 } 2866 2867 if (!*fmt) 2868 break; 2869 ++fmt; 2870 2871 /* skip this conversion. 2872 * advance both strings to next white space 2873 */ 2874 if (*fmt == '*') { 2875 if (!*str) 2876 break; 2877 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 2878 /* '%*[' not yet supported, invalid format */ 2879 if (*fmt == '[') 2880 return num; 2881 fmt++; 2882 } 2883 while (!isspace(*str) && *str) 2884 str++; 2885 continue; 2886 } 2887 2888 /* get field width */ 2889 field_width = -1; 2890 if (isdigit(*fmt)) { 2891 field_width = skip_atoi(&fmt); 2892 if (field_width <= 0) 2893 break; 2894 } 2895 2896 /* get conversion qualifier */ 2897 qualifier = -1; 2898 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2899 *fmt == 'z') { 2900 qualifier = *fmt++; 2901 if (unlikely(qualifier == *fmt)) { 2902 if (qualifier == 'h') { 2903 qualifier = 'H'; 2904 fmt++; 2905 } else if (qualifier == 'l') { 2906 qualifier = 'L'; 2907 fmt++; 2908 } 2909 } 2910 } 2911 2912 if (!*fmt) 2913 break; 2914 2915 if (*fmt == 'n') { 2916 /* return number of characters read so far */ 2917 *va_arg(args, int *) = str - buf; 2918 ++fmt; 2919 continue; 2920 } 2921 2922 if (!*str) 2923 break; 2924 2925 base = 10; 2926 is_sign = false; 2927 2928 switch (*fmt++) { 2929 case 'c': 2930 { 2931 char *s = (char *)va_arg(args, char*); 2932 if (field_width == -1) 2933 field_width = 1; 2934 do { 2935 *s++ = *str++; 2936 } while (--field_width > 0 && *str); 2937 num++; 2938 } 2939 continue; 2940 case 's': 2941 { 2942 char *s = (char *)va_arg(args, char *); 2943 if (field_width == -1) 2944 field_width = SHRT_MAX; 2945 /* first, skip leading white space in buffer */ 2946 str = skip_spaces(str); 2947 2948 /* now copy until next white space */ 2949 while (*str && !isspace(*str) && field_width--) 2950 *s++ = *str++; 2951 *s = '\0'; 2952 num++; 2953 } 2954 continue; 2955 /* 2956 * Warning: This implementation of the '[' conversion specifier 2957 * deviates from its glibc counterpart in the following ways: 2958 * (1) It does NOT support ranges i.e. '-' is NOT a special 2959 * character 2960 * (2) It cannot match the closing bracket ']' itself 2961 * (3) A field width is required 2962 * (4) '%*[' (discard matching input) is currently not supported 2963 * 2964 * Example usage: 2965 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 2966 * buf1, buf2, buf3); 2967 * if (ret < 3) 2968 * // etc.. 2969 */ 2970 case '[': 2971 { 2972 char *s = (char *)va_arg(args, char *); 2973 DECLARE_BITMAP(set, 256) = {0}; 2974 unsigned int len = 0; 2975 bool negate = (*fmt == '^'); 2976 2977 /* field width is required */ 2978 if (field_width == -1) 2979 return num; 2980 2981 if (negate) 2982 ++fmt; 2983 2984 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 2985 set_bit((u8)*fmt, set); 2986 2987 /* no ']' or no character set found */ 2988 if (!*fmt || !len) 2989 return num; 2990 ++fmt; 2991 2992 if (negate) { 2993 bitmap_complement(set, set, 256); 2994 /* exclude null '\0' byte */ 2995 clear_bit(0, set); 2996 } 2997 2998 /* match must be non-empty */ 2999 if (!test_bit((u8)*str, set)) 3000 return num; 3001 3002 while (test_bit((u8)*str, set) && field_width--) 3003 *s++ = *str++; 3004 *s = '\0'; 3005 ++num; 3006 } 3007 continue; 3008 case 'o': 3009 base = 8; 3010 break; 3011 case 'x': 3012 case 'X': 3013 base = 16; 3014 break; 3015 case 'i': 3016 base = 0; 3017 case 'd': 3018 is_sign = true; 3019 case 'u': 3020 break; 3021 case '%': 3022 /* looking for '%' in str */ 3023 if (*str++ != '%') 3024 return num; 3025 continue; 3026 default: 3027 /* invalid format; stop here */ 3028 return num; 3029 } 3030 3031 /* have some sort of integer conversion. 3032 * first, skip white space in buffer. 3033 */ 3034 str = skip_spaces(str); 3035 3036 digit = *str; 3037 if (is_sign && digit == '-') 3038 digit = *(str + 1); 3039 3040 if (!digit 3041 || (base == 16 && !isxdigit(digit)) 3042 || (base == 10 && !isdigit(digit)) 3043 || (base == 8 && (!isdigit(digit) || digit > '7')) 3044 || (base == 0 && !isdigit(digit))) 3045 break; 3046 3047 if (is_sign) 3048 val.s = qualifier != 'L' ? 3049 simple_strtol(str, &next, base) : 3050 simple_strtoll(str, &next, base); 3051 else 3052 val.u = qualifier != 'L' ? 3053 simple_strtoul(str, &next, base) : 3054 simple_strtoull(str, &next, base); 3055 3056 if (field_width > 0 && next - str > field_width) { 3057 if (base == 0) 3058 _parse_integer_fixup_radix(str, &base); 3059 while (next - str > field_width) { 3060 if (is_sign) 3061 val.s = div_s64(val.s, base); 3062 else 3063 val.u = div_u64(val.u, base); 3064 --next; 3065 } 3066 } 3067 3068 switch (qualifier) { 3069 case 'H': /* that's 'hh' in format */ 3070 if (is_sign) 3071 *va_arg(args, signed char *) = val.s; 3072 else 3073 *va_arg(args, unsigned char *) = val.u; 3074 break; 3075 case 'h': 3076 if (is_sign) 3077 *va_arg(args, short *) = val.s; 3078 else 3079 *va_arg(args, unsigned short *) = val.u; 3080 break; 3081 case 'l': 3082 if (is_sign) 3083 *va_arg(args, long *) = val.s; 3084 else 3085 *va_arg(args, unsigned long *) = val.u; 3086 break; 3087 case 'L': 3088 if (is_sign) 3089 *va_arg(args, long long *) = val.s; 3090 else 3091 *va_arg(args, unsigned long long *) = val.u; 3092 break; 3093 case 'z': 3094 *va_arg(args, size_t *) = val.u; 3095 break; 3096 default: 3097 if (is_sign) 3098 *va_arg(args, int *) = val.s; 3099 else 3100 *va_arg(args, unsigned int *) = val.u; 3101 break; 3102 } 3103 num++; 3104 3105 if (!next) 3106 break; 3107 str = next; 3108 } 3109 3110 return num; 3111 } 3112 EXPORT_SYMBOL(vsscanf); 3113 3114 /** 3115 * sscanf - Unformat a buffer into a list of arguments 3116 * @buf: input buffer 3117 * @fmt: formatting of buffer 3118 * @...: resulting arguments 3119 */ 3120 int sscanf(const char *buf, const char *fmt, ...) 3121 { 3122 va_list args; 3123 int i; 3124 3125 va_start(args, fmt); 3126 i = vsscanf(buf, fmt, args); 3127 va_end(args); 3128 3129 return i; 3130 } 3131 EXPORT_SYMBOL(sscanf); 3132