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/byteorder.h> /* cpu_to_le16 */ 46 47 #include <linux/string_helpers.h> 48 #include "kstrtox.h" 49 50 /** 51 * simple_strtoull - convert a string to an unsigned long long 52 * @cp: The start of the string 53 * @endp: A pointer to the end of the parsed string will be placed here 54 * @base: The number base to use 55 * 56 * This function is obsolete. Please use kstrtoull instead. 57 */ 58 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 59 { 60 unsigned long long result; 61 unsigned int rv; 62 63 cp = _parse_integer_fixup_radix(cp, &base); 64 rv = _parse_integer(cp, base, &result); 65 /* FIXME */ 66 cp += (rv & ~KSTRTOX_OVERFLOW); 67 68 if (endp) 69 *endp = (char *)cp; 70 71 return result; 72 } 73 EXPORT_SYMBOL(simple_strtoull); 74 75 /** 76 * simple_strtoul - convert a string to an unsigned long 77 * @cp: The start of the string 78 * @endp: A pointer to the end of the parsed string will be placed here 79 * @base: The number base to use 80 * 81 * This function is obsolete. Please use kstrtoul instead. 82 */ 83 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 84 { 85 return simple_strtoull(cp, endp, base); 86 } 87 EXPORT_SYMBOL(simple_strtoul); 88 89 /** 90 * simple_strtol - convert a string to a signed long 91 * @cp: The start of the string 92 * @endp: A pointer to the end of the parsed string will be placed here 93 * @base: The number base to use 94 * 95 * This function is obsolete. Please use kstrtol instead. 96 */ 97 long simple_strtol(const char *cp, char **endp, unsigned int base) 98 { 99 if (*cp == '-') 100 return -simple_strtoul(cp + 1, endp, base); 101 102 return simple_strtoul(cp, endp, base); 103 } 104 EXPORT_SYMBOL(simple_strtol); 105 106 /** 107 * simple_strtoll - convert a string to a signed long long 108 * @cp: The start of the string 109 * @endp: A pointer to the end of the parsed string will be placed here 110 * @base: The number base to use 111 * 112 * This function is obsolete. Please use kstrtoll instead. 113 */ 114 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 115 { 116 if (*cp == '-') 117 return -simple_strtoull(cp + 1, endp, base); 118 119 return simple_strtoull(cp, endp, base); 120 } 121 EXPORT_SYMBOL(simple_strtoll); 122 123 static noinline_for_stack 124 int skip_atoi(const char **s) 125 { 126 int i = 0; 127 128 do { 129 i = i*10 + *((*s)++) - '0'; 130 } while (isdigit(**s)); 131 132 return i; 133 } 134 135 /* 136 * Decimal conversion is by far the most typical, and is used for 137 * /proc and /sys data. This directly impacts e.g. top performance 138 * with many processes running. We optimize it for speed by emitting 139 * two characters at a time, using a 200 byte lookup table. This 140 * roughly halves the number of multiplications compared to computing 141 * the digits one at a time. Implementation strongly inspired by the 142 * previous version, which in turn used ideas described at 143 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 144 * from the author, Douglas W. Jones). 145 * 146 * It turns out there is precisely one 26 bit fixed-point 147 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 148 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 149 * range happens to be somewhat larger (x <= 1073741898), but that's 150 * irrelevant for our purpose. 151 * 152 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 153 * need a 32x32->64 bit multiply, so we simply use the same constant. 154 * 155 * For dividing a number in the range [100, 10^4-1] by 100, there are 156 * several options. The simplest is (x * 0x147b) >> 19, which is valid 157 * for all x <= 43698. 158 */ 159 160 static const u16 decpair[100] = { 161 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 162 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 163 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 164 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 165 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 166 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 167 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 168 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 169 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 170 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 171 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 172 #undef _ 173 }; 174 175 /* 176 * This will print a single '0' even if r == 0, since we would 177 * immediately jump to out_r where two 0s would be written but only 178 * one of them accounted for in buf. This is needed by ip4_string 179 * below. All other callers pass a non-zero value of r. 180 */ 181 static noinline_for_stack 182 char *put_dec_trunc8(char *buf, unsigned r) 183 { 184 unsigned q; 185 186 /* 1 <= r < 10^8 */ 187 if (r < 100) 188 goto out_r; 189 190 /* 100 <= r < 10^8 */ 191 q = (r * (u64)0x28f5c29) >> 32; 192 *((u16 *)buf) = decpair[r - 100*q]; 193 buf += 2; 194 195 /* 1 <= q < 10^6 */ 196 if (q < 100) 197 goto out_q; 198 199 /* 100 <= q < 10^6 */ 200 r = (q * (u64)0x28f5c29) >> 32; 201 *((u16 *)buf) = decpair[q - 100*r]; 202 buf += 2; 203 204 /* 1 <= r < 10^4 */ 205 if (r < 100) 206 goto out_r; 207 208 /* 100 <= r < 10^4 */ 209 q = (r * 0x147b) >> 19; 210 *((u16 *)buf) = decpair[r - 100*q]; 211 buf += 2; 212 out_q: 213 /* 1 <= q < 100 */ 214 r = q; 215 out_r: 216 /* 1 <= r < 100 */ 217 *((u16 *)buf) = decpair[r]; 218 buf += r < 10 ? 1 : 2; 219 return buf; 220 } 221 222 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 223 static noinline_for_stack 224 char *put_dec_full8(char *buf, unsigned r) 225 { 226 unsigned q; 227 228 /* 0 <= r < 10^8 */ 229 q = (r * (u64)0x28f5c29) >> 32; 230 *((u16 *)buf) = decpair[r - 100*q]; 231 buf += 2; 232 233 /* 0 <= q < 10^6 */ 234 r = (q * (u64)0x28f5c29) >> 32; 235 *((u16 *)buf) = decpair[q - 100*r]; 236 buf += 2; 237 238 /* 0 <= r < 10^4 */ 239 q = (r * 0x147b) >> 19; 240 *((u16 *)buf) = decpair[r - 100*q]; 241 buf += 2; 242 243 /* 0 <= q < 100 */ 244 *((u16 *)buf) = decpair[q]; 245 buf += 2; 246 return buf; 247 } 248 249 static noinline_for_stack 250 char *put_dec(char *buf, unsigned long long n) 251 { 252 if (n >= 100*1000*1000) 253 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 254 /* 1 <= n <= 1.6e11 */ 255 if (n >= 100*1000*1000) 256 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 257 /* 1 <= n < 1e8 */ 258 return put_dec_trunc8(buf, n); 259 } 260 261 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 262 263 static void 264 put_dec_full4(char *buf, unsigned r) 265 { 266 unsigned q; 267 268 /* 0 <= r < 10^4 */ 269 q = (r * 0x147b) >> 19; 270 *((u16 *)buf) = decpair[r - 100*q]; 271 buf += 2; 272 /* 0 <= q < 100 */ 273 *((u16 *)buf) = decpair[q]; 274 } 275 276 /* 277 * Call put_dec_full4 on x % 10000, return x / 10000. 278 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 279 * holds for all x < 1,128,869,999. The largest value this 280 * helper will ever be asked to convert is 1,125,520,955. 281 * (second call in the put_dec code, assuming n is all-ones). 282 */ 283 static noinline_for_stack 284 unsigned put_dec_helper4(char *buf, unsigned x) 285 { 286 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 287 288 put_dec_full4(buf, x - q * 10000); 289 return q; 290 } 291 292 /* Based on code by Douglas W. Jones found at 293 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 294 * (with permission from the author). 295 * Performs no 64-bit division and hence should be fast on 32-bit machines. 296 */ 297 static 298 char *put_dec(char *buf, unsigned long long n) 299 { 300 uint32_t d3, d2, d1, q, h; 301 302 if (n < 100*1000*1000) 303 return put_dec_trunc8(buf, n); 304 305 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 306 h = (n >> 32); 307 d2 = (h ) & 0xffff; 308 d3 = (h >> 16); /* implicit "& 0xffff" */ 309 310 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 311 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 312 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 313 q = put_dec_helper4(buf, q); 314 315 q += 7671 * d3 + 9496 * d2 + 6 * d1; 316 q = put_dec_helper4(buf+4, q); 317 318 q += 4749 * d3 + 42 * d2; 319 q = put_dec_helper4(buf+8, q); 320 321 q += 281 * d3; 322 buf += 12; 323 if (q) 324 buf = put_dec_trunc8(buf, q); 325 else while (buf[-1] == '0') 326 --buf; 327 328 return buf; 329 } 330 331 #endif 332 333 /* 334 * Convert passed number to decimal string. 335 * Returns the length of string. On buffer overflow, returns 0. 336 * 337 * If speed is not important, use snprintf(). It's easy to read the code. 338 */ 339 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 340 { 341 /* put_dec requires 2-byte alignment of the buffer. */ 342 char tmp[sizeof(num) * 3] __aligned(2); 343 int idx, len; 344 345 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 346 if (num <= 9) { 347 tmp[0] = '0' + num; 348 len = 1; 349 } else { 350 len = put_dec(tmp, num) - tmp; 351 } 352 353 if (len > size || width > size) 354 return 0; 355 356 if (width > len) { 357 width = width - len; 358 for (idx = 0; idx < width; idx++) 359 buf[idx] = ' '; 360 } else { 361 width = 0; 362 } 363 364 for (idx = 0; idx < len; ++idx) 365 buf[idx + width] = tmp[len - idx - 1]; 366 367 return len + width; 368 } 369 370 #define SIGN 1 /* unsigned/signed, must be 1 */ 371 #define LEFT 2 /* left justified */ 372 #define PLUS 4 /* show plus */ 373 #define SPACE 8 /* space if plus */ 374 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 375 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 376 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 377 378 enum format_type { 379 FORMAT_TYPE_NONE, /* Just a string part */ 380 FORMAT_TYPE_WIDTH, 381 FORMAT_TYPE_PRECISION, 382 FORMAT_TYPE_CHAR, 383 FORMAT_TYPE_STR, 384 FORMAT_TYPE_PTR, 385 FORMAT_TYPE_PERCENT_CHAR, 386 FORMAT_TYPE_INVALID, 387 FORMAT_TYPE_LONG_LONG, 388 FORMAT_TYPE_ULONG, 389 FORMAT_TYPE_LONG, 390 FORMAT_TYPE_UBYTE, 391 FORMAT_TYPE_BYTE, 392 FORMAT_TYPE_USHORT, 393 FORMAT_TYPE_SHORT, 394 FORMAT_TYPE_UINT, 395 FORMAT_TYPE_INT, 396 FORMAT_TYPE_SIZE_T, 397 FORMAT_TYPE_PTRDIFF 398 }; 399 400 struct printf_spec { 401 unsigned int type:8; /* format_type enum */ 402 signed int field_width:24; /* width of output field */ 403 unsigned int flags:8; /* flags to number() */ 404 unsigned int base:8; /* number base, 8, 10 or 16 only */ 405 signed int precision:16; /* # of digits/chars */ 406 } __packed; 407 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 408 #define PRECISION_MAX ((1 << 15) - 1) 409 410 static noinline_for_stack 411 char *number(char *buf, char *end, unsigned long long num, 412 struct printf_spec spec) 413 { 414 /* put_dec requires 2-byte alignment of the buffer. */ 415 char tmp[3 * sizeof(num)] __aligned(2); 416 char sign; 417 char locase; 418 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 419 int i; 420 bool is_zero = num == 0LL; 421 int field_width = spec.field_width; 422 int precision = spec.precision; 423 424 BUILD_BUG_ON(sizeof(struct printf_spec) != 8); 425 426 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 427 * produces same digits or (maybe lowercased) letters */ 428 locase = (spec.flags & SMALL); 429 if (spec.flags & LEFT) 430 spec.flags &= ~ZEROPAD; 431 sign = 0; 432 if (spec.flags & SIGN) { 433 if ((signed long long)num < 0) { 434 sign = '-'; 435 num = -(signed long long)num; 436 field_width--; 437 } else if (spec.flags & PLUS) { 438 sign = '+'; 439 field_width--; 440 } else if (spec.flags & SPACE) { 441 sign = ' '; 442 field_width--; 443 } 444 } 445 if (need_pfx) { 446 if (spec.base == 16) 447 field_width -= 2; 448 else if (!is_zero) 449 field_width--; 450 } 451 452 /* generate full string in tmp[], in reverse order */ 453 i = 0; 454 if (num < spec.base) 455 tmp[i++] = hex_asc_upper[num] | locase; 456 else if (spec.base != 10) { /* 8 or 16 */ 457 int mask = spec.base - 1; 458 int shift = 3; 459 460 if (spec.base == 16) 461 shift = 4; 462 do { 463 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 464 num >>= shift; 465 } while (num); 466 } else { /* base 10 */ 467 i = put_dec(tmp, num) - tmp; 468 } 469 470 /* printing 100 using %2d gives "100", not "00" */ 471 if (i > precision) 472 precision = i; 473 /* leading space padding */ 474 field_width -= precision; 475 if (!(spec.flags & (ZEROPAD | LEFT))) { 476 while (--field_width >= 0) { 477 if (buf < end) 478 *buf = ' '; 479 ++buf; 480 } 481 } 482 /* sign */ 483 if (sign) { 484 if (buf < end) 485 *buf = sign; 486 ++buf; 487 } 488 /* "0x" / "0" prefix */ 489 if (need_pfx) { 490 if (spec.base == 16 || !is_zero) { 491 if (buf < end) 492 *buf = '0'; 493 ++buf; 494 } 495 if (spec.base == 16) { 496 if (buf < end) 497 *buf = ('X' | locase); 498 ++buf; 499 } 500 } 501 /* zero or space padding */ 502 if (!(spec.flags & LEFT)) { 503 char c = ' ' + (spec.flags & ZEROPAD); 504 BUILD_BUG_ON(' ' + ZEROPAD != '0'); 505 while (--field_width >= 0) { 506 if (buf < end) 507 *buf = c; 508 ++buf; 509 } 510 } 511 /* hmm even more zero padding? */ 512 while (i <= --precision) { 513 if (buf < end) 514 *buf = '0'; 515 ++buf; 516 } 517 /* actual digits of result */ 518 while (--i >= 0) { 519 if (buf < end) 520 *buf = tmp[i]; 521 ++buf; 522 } 523 /* trailing space padding */ 524 while (--field_width >= 0) { 525 if (buf < end) 526 *buf = ' '; 527 ++buf; 528 } 529 530 return buf; 531 } 532 533 static noinline_for_stack 534 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 535 { 536 struct printf_spec spec; 537 538 spec.type = FORMAT_TYPE_PTR; 539 spec.field_width = 2 + 2 * size; /* 0x + hex */ 540 spec.flags = SPECIAL | SMALL | ZEROPAD; 541 spec.base = 16; 542 spec.precision = -1; 543 544 return number(buf, end, num, spec); 545 } 546 547 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 548 { 549 size_t size; 550 if (buf >= end) /* nowhere to put anything */ 551 return; 552 size = end - buf; 553 if (size <= spaces) { 554 memset(buf, ' ', size); 555 return; 556 } 557 if (len) { 558 if (len > size - spaces) 559 len = size - spaces; 560 memmove(buf + spaces, buf, len); 561 } 562 memset(buf, ' ', spaces); 563 } 564 565 /* 566 * Handle field width padding for a string. 567 * @buf: current buffer position 568 * @n: length of string 569 * @end: end of output buffer 570 * @spec: for field width and flags 571 * Returns: new buffer position after padding. 572 */ 573 static noinline_for_stack 574 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 575 { 576 unsigned spaces; 577 578 if (likely(n >= spec.field_width)) 579 return buf; 580 /* we want to pad the sucker */ 581 spaces = spec.field_width - n; 582 if (!(spec.flags & LEFT)) { 583 move_right(buf - n, end, n, spaces); 584 return buf + spaces; 585 } 586 while (spaces--) { 587 if (buf < end) 588 *buf = ' '; 589 ++buf; 590 } 591 return buf; 592 } 593 594 static noinline_for_stack 595 char *string(char *buf, char *end, const char *s, struct printf_spec spec) 596 { 597 int len = 0; 598 size_t lim = spec.precision; 599 600 if ((unsigned long)s < PAGE_SIZE) 601 s = "(null)"; 602 603 while (lim--) { 604 char c = *s++; 605 if (!c) 606 break; 607 if (buf < end) 608 *buf = c; 609 ++buf; 610 ++len; 611 } 612 return widen_string(buf, len, end, spec); 613 } 614 615 static noinline_for_stack 616 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 617 const char *fmt) 618 { 619 const char *array[4], *s; 620 const struct dentry *p; 621 int depth; 622 int i, n; 623 624 switch (fmt[1]) { 625 case '2': case '3': case '4': 626 depth = fmt[1] - '0'; 627 break; 628 default: 629 depth = 1; 630 } 631 632 rcu_read_lock(); 633 for (i = 0; i < depth; i++, d = p) { 634 p = READ_ONCE(d->d_parent); 635 array[i] = READ_ONCE(d->d_name.name); 636 if (p == d) { 637 if (i) 638 array[i] = ""; 639 i++; 640 break; 641 } 642 } 643 s = array[--i]; 644 for (n = 0; n != spec.precision; n++, buf++) { 645 char c = *s++; 646 if (!c) { 647 if (!i) 648 break; 649 c = '/'; 650 s = array[--i]; 651 } 652 if (buf < end) 653 *buf = c; 654 } 655 rcu_read_unlock(); 656 return widen_string(buf, n, end, spec); 657 } 658 659 #ifdef CONFIG_BLOCK 660 static noinline_for_stack 661 char *bdev_name(char *buf, char *end, struct block_device *bdev, 662 struct printf_spec spec, const char *fmt) 663 { 664 struct gendisk *hd = bdev->bd_disk; 665 666 buf = string(buf, end, hd->disk_name, spec); 667 if (bdev->bd_part->partno) { 668 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 669 if (buf < end) 670 *buf = 'p'; 671 buf++; 672 } 673 buf = number(buf, end, bdev->bd_part->partno, spec); 674 } 675 return buf; 676 } 677 #endif 678 679 static noinline_for_stack 680 char *symbol_string(char *buf, char *end, void *ptr, 681 struct printf_spec spec, const char *fmt) 682 { 683 unsigned long value; 684 #ifdef CONFIG_KALLSYMS 685 char sym[KSYM_SYMBOL_LEN]; 686 #endif 687 688 if (fmt[1] == 'R') 689 ptr = __builtin_extract_return_addr(ptr); 690 value = (unsigned long)ptr; 691 692 #ifdef CONFIG_KALLSYMS 693 if (*fmt == 'B') 694 sprint_backtrace(sym, value); 695 else if (*fmt != 'f' && *fmt != 's') 696 sprint_symbol(sym, value); 697 else 698 sprint_symbol_no_offset(sym, value); 699 700 return string(buf, end, sym, spec); 701 #else 702 return special_hex_number(buf, end, value, sizeof(void *)); 703 #endif 704 } 705 706 static const struct printf_spec default_str_spec = { 707 .field_width = -1, 708 .precision = -1, 709 }; 710 711 static const struct printf_spec default_flag_spec = { 712 .base = 16, 713 .precision = -1, 714 .flags = SPECIAL | SMALL, 715 }; 716 717 static const struct printf_spec default_dec_spec = { 718 .base = 10, 719 .precision = -1, 720 }; 721 722 static noinline_for_stack 723 char *resource_string(char *buf, char *end, struct resource *res, 724 struct printf_spec spec, const char *fmt) 725 { 726 #ifndef IO_RSRC_PRINTK_SIZE 727 #define IO_RSRC_PRINTK_SIZE 6 728 #endif 729 730 #ifndef MEM_RSRC_PRINTK_SIZE 731 #define MEM_RSRC_PRINTK_SIZE 10 732 #endif 733 static const struct printf_spec io_spec = { 734 .base = 16, 735 .field_width = IO_RSRC_PRINTK_SIZE, 736 .precision = -1, 737 .flags = SPECIAL | SMALL | ZEROPAD, 738 }; 739 static const struct printf_spec mem_spec = { 740 .base = 16, 741 .field_width = MEM_RSRC_PRINTK_SIZE, 742 .precision = -1, 743 .flags = SPECIAL | SMALL | ZEROPAD, 744 }; 745 static const struct printf_spec bus_spec = { 746 .base = 16, 747 .field_width = 2, 748 .precision = -1, 749 .flags = SMALL | ZEROPAD, 750 }; 751 static const struct printf_spec str_spec = { 752 .field_width = -1, 753 .precision = 10, 754 .flags = LEFT, 755 }; 756 757 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 758 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 759 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 760 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 761 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 762 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 763 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 764 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 765 766 char *p = sym, *pend = sym + sizeof(sym); 767 int decode = (fmt[0] == 'R') ? 1 : 0; 768 const struct printf_spec *specp; 769 770 *p++ = '['; 771 if (res->flags & IORESOURCE_IO) { 772 p = string(p, pend, "io ", str_spec); 773 specp = &io_spec; 774 } else if (res->flags & IORESOURCE_MEM) { 775 p = string(p, pend, "mem ", str_spec); 776 specp = &mem_spec; 777 } else if (res->flags & IORESOURCE_IRQ) { 778 p = string(p, pend, "irq ", str_spec); 779 specp = &default_dec_spec; 780 } else if (res->flags & IORESOURCE_DMA) { 781 p = string(p, pend, "dma ", str_spec); 782 specp = &default_dec_spec; 783 } else if (res->flags & IORESOURCE_BUS) { 784 p = string(p, pend, "bus ", str_spec); 785 specp = &bus_spec; 786 } else { 787 p = string(p, pend, "??? ", str_spec); 788 specp = &mem_spec; 789 decode = 0; 790 } 791 if (decode && res->flags & IORESOURCE_UNSET) { 792 p = string(p, pend, "size ", str_spec); 793 p = number(p, pend, resource_size(res), *specp); 794 } else { 795 p = number(p, pend, res->start, *specp); 796 if (res->start != res->end) { 797 *p++ = '-'; 798 p = number(p, pend, res->end, *specp); 799 } 800 } 801 if (decode) { 802 if (res->flags & IORESOURCE_MEM_64) 803 p = string(p, pend, " 64bit", str_spec); 804 if (res->flags & IORESOURCE_PREFETCH) 805 p = string(p, pend, " pref", str_spec); 806 if (res->flags & IORESOURCE_WINDOW) 807 p = string(p, pend, " window", str_spec); 808 if (res->flags & IORESOURCE_DISABLED) 809 p = string(p, pend, " disabled", str_spec); 810 } else { 811 p = string(p, pend, " flags ", str_spec); 812 p = number(p, pend, res->flags, default_flag_spec); 813 } 814 *p++ = ']'; 815 *p = '\0'; 816 817 return string(buf, end, sym, spec); 818 } 819 820 static noinline_for_stack 821 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 822 const char *fmt) 823 { 824 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 825 negative value, fallback to the default */ 826 char separator; 827 828 if (spec.field_width == 0) 829 /* nothing to print */ 830 return buf; 831 832 if (ZERO_OR_NULL_PTR(addr)) 833 /* NULL pointer */ 834 return string(buf, end, NULL, spec); 835 836 switch (fmt[1]) { 837 case 'C': 838 separator = ':'; 839 break; 840 case 'D': 841 separator = '-'; 842 break; 843 case 'N': 844 separator = 0; 845 break; 846 default: 847 separator = ' '; 848 break; 849 } 850 851 if (spec.field_width > 0) 852 len = min_t(int, spec.field_width, 64); 853 854 for (i = 0; i < len; ++i) { 855 if (buf < end) 856 *buf = hex_asc_hi(addr[i]); 857 ++buf; 858 if (buf < end) 859 *buf = hex_asc_lo(addr[i]); 860 ++buf; 861 862 if (separator && i != len - 1) { 863 if (buf < end) 864 *buf = separator; 865 ++buf; 866 } 867 } 868 869 return buf; 870 } 871 872 static noinline_for_stack 873 char *bitmap_string(char *buf, char *end, unsigned long *bitmap, 874 struct printf_spec spec, const char *fmt) 875 { 876 const int CHUNKSZ = 32; 877 int nr_bits = max_t(int, spec.field_width, 0); 878 int i, chunksz; 879 bool first = true; 880 881 /* reused to print numbers */ 882 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 883 884 chunksz = nr_bits & (CHUNKSZ - 1); 885 if (chunksz == 0) 886 chunksz = CHUNKSZ; 887 888 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 889 for (; i >= 0; i -= CHUNKSZ) { 890 u32 chunkmask, val; 891 int word, bit; 892 893 chunkmask = ((1ULL << chunksz) - 1); 894 word = i / BITS_PER_LONG; 895 bit = i % BITS_PER_LONG; 896 val = (bitmap[word] >> bit) & chunkmask; 897 898 if (!first) { 899 if (buf < end) 900 *buf = ','; 901 buf++; 902 } 903 first = false; 904 905 spec.field_width = DIV_ROUND_UP(chunksz, 4); 906 buf = number(buf, end, val, spec); 907 908 chunksz = CHUNKSZ; 909 } 910 return buf; 911 } 912 913 static noinline_for_stack 914 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap, 915 struct printf_spec spec, const char *fmt) 916 { 917 int nr_bits = max_t(int, spec.field_width, 0); 918 /* current bit is 'cur', most recently seen range is [rbot, rtop] */ 919 int cur, rbot, rtop; 920 bool first = true; 921 922 rbot = cur = find_first_bit(bitmap, nr_bits); 923 while (cur < nr_bits) { 924 rtop = cur; 925 cur = find_next_bit(bitmap, nr_bits, cur + 1); 926 if (cur < nr_bits && cur <= rtop + 1) 927 continue; 928 929 if (!first) { 930 if (buf < end) 931 *buf = ','; 932 buf++; 933 } 934 first = false; 935 936 buf = number(buf, end, rbot, default_dec_spec); 937 if (rbot < rtop) { 938 if (buf < end) 939 *buf = '-'; 940 buf++; 941 942 buf = number(buf, end, rtop, default_dec_spec); 943 } 944 945 rbot = cur; 946 } 947 return buf; 948 } 949 950 static noinline_for_stack 951 char *mac_address_string(char *buf, char *end, u8 *addr, 952 struct printf_spec spec, const char *fmt) 953 { 954 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 955 char *p = mac_addr; 956 int i; 957 char separator; 958 bool reversed = false; 959 960 switch (fmt[1]) { 961 case 'F': 962 separator = '-'; 963 break; 964 965 case 'R': 966 reversed = true; 967 /* fall through */ 968 969 default: 970 separator = ':'; 971 break; 972 } 973 974 for (i = 0; i < 6; i++) { 975 if (reversed) 976 p = hex_byte_pack(p, addr[5 - i]); 977 else 978 p = hex_byte_pack(p, addr[i]); 979 980 if (fmt[0] == 'M' && i != 5) 981 *p++ = separator; 982 } 983 *p = '\0'; 984 985 return string(buf, end, mac_addr, spec); 986 } 987 988 static noinline_for_stack 989 char *ip4_string(char *p, const u8 *addr, const char *fmt) 990 { 991 int i; 992 bool leading_zeros = (fmt[0] == 'i'); 993 int index; 994 int step; 995 996 switch (fmt[2]) { 997 case 'h': 998 #ifdef __BIG_ENDIAN 999 index = 0; 1000 step = 1; 1001 #else 1002 index = 3; 1003 step = -1; 1004 #endif 1005 break; 1006 case 'l': 1007 index = 3; 1008 step = -1; 1009 break; 1010 case 'n': 1011 case 'b': 1012 default: 1013 index = 0; 1014 step = 1; 1015 break; 1016 } 1017 for (i = 0; i < 4; i++) { 1018 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1019 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1020 if (leading_zeros) { 1021 if (digits < 3) 1022 *p++ = '0'; 1023 if (digits < 2) 1024 *p++ = '0'; 1025 } 1026 /* reverse the digits in the quad */ 1027 while (digits--) 1028 *p++ = temp[digits]; 1029 if (i < 3) 1030 *p++ = '.'; 1031 index += step; 1032 } 1033 *p = '\0'; 1034 1035 return p; 1036 } 1037 1038 static noinline_for_stack 1039 char *ip6_compressed_string(char *p, const char *addr) 1040 { 1041 int i, j, range; 1042 unsigned char zerolength[8]; 1043 int longest = 1; 1044 int colonpos = -1; 1045 u16 word; 1046 u8 hi, lo; 1047 bool needcolon = false; 1048 bool useIPv4; 1049 struct in6_addr in6; 1050 1051 memcpy(&in6, addr, sizeof(struct in6_addr)); 1052 1053 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1054 1055 memset(zerolength, 0, sizeof(zerolength)); 1056 1057 if (useIPv4) 1058 range = 6; 1059 else 1060 range = 8; 1061 1062 /* find position of longest 0 run */ 1063 for (i = 0; i < range; i++) { 1064 for (j = i; j < range; j++) { 1065 if (in6.s6_addr16[j] != 0) 1066 break; 1067 zerolength[i]++; 1068 } 1069 } 1070 for (i = 0; i < range; i++) { 1071 if (zerolength[i] > longest) { 1072 longest = zerolength[i]; 1073 colonpos = i; 1074 } 1075 } 1076 if (longest == 1) /* don't compress a single 0 */ 1077 colonpos = -1; 1078 1079 /* emit address */ 1080 for (i = 0; i < range; i++) { 1081 if (i == colonpos) { 1082 if (needcolon || i == 0) 1083 *p++ = ':'; 1084 *p++ = ':'; 1085 needcolon = false; 1086 i += longest - 1; 1087 continue; 1088 } 1089 if (needcolon) { 1090 *p++ = ':'; 1091 needcolon = false; 1092 } 1093 /* hex u16 without leading 0s */ 1094 word = ntohs(in6.s6_addr16[i]); 1095 hi = word >> 8; 1096 lo = word & 0xff; 1097 if (hi) { 1098 if (hi > 0x0f) 1099 p = hex_byte_pack(p, hi); 1100 else 1101 *p++ = hex_asc_lo(hi); 1102 p = hex_byte_pack(p, lo); 1103 } 1104 else if (lo > 0x0f) 1105 p = hex_byte_pack(p, lo); 1106 else 1107 *p++ = hex_asc_lo(lo); 1108 needcolon = true; 1109 } 1110 1111 if (useIPv4) { 1112 if (needcolon) 1113 *p++ = ':'; 1114 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1115 } 1116 *p = '\0'; 1117 1118 return p; 1119 } 1120 1121 static noinline_for_stack 1122 char *ip6_string(char *p, const char *addr, const char *fmt) 1123 { 1124 int i; 1125 1126 for (i = 0; i < 8; i++) { 1127 p = hex_byte_pack(p, *addr++); 1128 p = hex_byte_pack(p, *addr++); 1129 if (fmt[0] == 'I' && i != 7) 1130 *p++ = ':'; 1131 } 1132 *p = '\0'; 1133 1134 return p; 1135 } 1136 1137 static noinline_for_stack 1138 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1139 struct printf_spec spec, const char *fmt) 1140 { 1141 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1142 1143 if (fmt[0] == 'I' && fmt[2] == 'c') 1144 ip6_compressed_string(ip6_addr, addr); 1145 else 1146 ip6_string(ip6_addr, addr, fmt); 1147 1148 return string(buf, end, ip6_addr, spec); 1149 } 1150 1151 static noinline_for_stack 1152 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1153 struct printf_spec spec, const char *fmt) 1154 { 1155 char ip4_addr[sizeof("255.255.255.255")]; 1156 1157 ip4_string(ip4_addr, addr, fmt); 1158 1159 return string(buf, end, ip4_addr, spec); 1160 } 1161 1162 static noinline_for_stack 1163 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1164 struct printf_spec spec, const char *fmt) 1165 { 1166 bool have_p = false, have_s = false, have_f = false, have_c = false; 1167 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1168 sizeof(":12345") + sizeof("/123456789") + 1169 sizeof("%1234567890")]; 1170 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1171 const u8 *addr = (const u8 *) &sa->sin6_addr; 1172 char fmt6[2] = { fmt[0], '6' }; 1173 u8 off = 0; 1174 1175 fmt++; 1176 while (isalpha(*++fmt)) { 1177 switch (*fmt) { 1178 case 'p': 1179 have_p = true; 1180 break; 1181 case 'f': 1182 have_f = true; 1183 break; 1184 case 's': 1185 have_s = true; 1186 break; 1187 case 'c': 1188 have_c = true; 1189 break; 1190 } 1191 } 1192 1193 if (have_p || have_s || have_f) { 1194 *p = '['; 1195 off = 1; 1196 } 1197 1198 if (fmt6[0] == 'I' && have_c) 1199 p = ip6_compressed_string(ip6_addr + off, addr); 1200 else 1201 p = ip6_string(ip6_addr + off, addr, fmt6); 1202 1203 if (have_p || have_s || have_f) 1204 *p++ = ']'; 1205 1206 if (have_p) { 1207 *p++ = ':'; 1208 p = number(p, pend, ntohs(sa->sin6_port), spec); 1209 } 1210 if (have_f) { 1211 *p++ = '/'; 1212 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1213 IPV6_FLOWINFO_MASK), spec); 1214 } 1215 if (have_s) { 1216 *p++ = '%'; 1217 p = number(p, pend, sa->sin6_scope_id, spec); 1218 } 1219 *p = '\0'; 1220 1221 return string(buf, end, ip6_addr, spec); 1222 } 1223 1224 static noinline_for_stack 1225 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1226 struct printf_spec spec, const char *fmt) 1227 { 1228 bool have_p = false; 1229 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1230 char *pend = ip4_addr + sizeof(ip4_addr); 1231 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1232 char fmt4[3] = { fmt[0], '4', 0 }; 1233 1234 fmt++; 1235 while (isalpha(*++fmt)) { 1236 switch (*fmt) { 1237 case 'p': 1238 have_p = true; 1239 break; 1240 case 'h': 1241 case 'l': 1242 case 'n': 1243 case 'b': 1244 fmt4[2] = *fmt; 1245 break; 1246 } 1247 } 1248 1249 p = ip4_string(ip4_addr, addr, fmt4); 1250 if (have_p) { 1251 *p++ = ':'; 1252 p = number(p, pend, ntohs(sa->sin_port), spec); 1253 } 1254 *p = '\0'; 1255 1256 return string(buf, end, ip4_addr, spec); 1257 } 1258 1259 static noinline_for_stack 1260 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1261 const char *fmt) 1262 { 1263 bool found = true; 1264 int count = 1; 1265 unsigned int flags = 0; 1266 int len; 1267 1268 if (spec.field_width == 0) 1269 return buf; /* nothing to print */ 1270 1271 if (ZERO_OR_NULL_PTR(addr)) 1272 return string(buf, end, NULL, spec); /* NULL pointer */ 1273 1274 1275 do { 1276 switch (fmt[count++]) { 1277 case 'a': 1278 flags |= ESCAPE_ANY; 1279 break; 1280 case 'c': 1281 flags |= ESCAPE_SPECIAL; 1282 break; 1283 case 'h': 1284 flags |= ESCAPE_HEX; 1285 break; 1286 case 'n': 1287 flags |= ESCAPE_NULL; 1288 break; 1289 case 'o': 1290 flags |= ESCAPE_OCTAL; 1291 break; 1292 case 'p': 1293 flags |= ESCAPE_NP; 1294 break; 1295 case 's': 1296 flags |= ESCAPE_SPACE; 1297 break; 1298 default: 1299 found = false; 1300 break; 1301 } 1302 } while (found); 1303 1304 if (!flags) 1305 flags = ESCAPE_ANY_NP; 1306 1307 len = spec.field_width < 0 ? 1 : spec.field_width; 1308 1309 /* 1310 * string_escape_mem() writes as many characters as it can to 1311 * the given buffer, and returns the total size of the output 1312 * had the buffer been big enough. 1313 */ 1314 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1315 1316 return buf; 1317 } 1318 1319 static noinline_for_stack 1320 char *uuid_string(char *buf, char *end, const u8 *addr, 1321 struct printf_spec spec, const char *fmt) 1322 { 1323 char uuid[UUID_STRING_LEN + 1]; 1324 char *p = uuid; 1325 int i; 1326 const u8 *index = uuid_index; 1327 bool uc = false; 1328 1329 switch (*(++fmt)) { 1330 case 'L': 1331 uc = true; /* fall-through */ 1332 case 'l': 1333 index = guid_index; 1334 break; 1335 case 'B': 1336 uc = true; 1337 break; 1338 } 1339 1340 for (i = 0; i < 16; i++) { 1341 if (uc) 1342 p = hex_byte_pack_upper(p, addr[index[i]]); 1343 else 1344 p = hex_byte_pack(p, addr[index[i]]); 1345 switch (i) { 1346 case 3: 1347 case 5: 1348 case 7: 1349 case 9: 1350 *p++ = '-'; 1351 break; 1352 } 1353 } 1354 1355 *p = 0; 1356 1357 return string(buf, end, uuid, spec); 1358 } 1359 1360 static noinline_for_stack 1361 char *pointer_string(char *buf, char *end, const void *ptr, 1362 struct printf_spec spec) 1363 { 1364 spec.base = 16; 1365 spec.flags |= SMALL; 1366 if (spec.field_width == -1) { 1367 spec.field_width = 2 * sizeof(ptr); 1368 spec.flags |= ZEROPAD; 1369 } 1370 1371 return number(buf, end, (unsigned long int)ptr, spec); 1372 } 1373 1374 int kptr_restrict __read_mostly; 1375 1376 static noinline_for_stack 1377 char *restricted_pointer(char *buf, char *end, const void *ptr, 1378 struct printf_spec spec) 1379 { 1380 switch (kptr_restrict) { 1381 case 0: 1382 /* Always print %pK values */ 1383 break; 1384 case 1: { 1385 const struct cred *cred; 1386 1387 /* 1388 * kptr_restrict==1 cannot be used in IRQ context 1389 * because its test for CAP_SYSLOG would be meaningless. 1390 */ 1391 if (in_irq() || in_serving_softirq() || in_nmi()) { 1392 if (spec.field_width == -1) 1393 spec.field_width = 2 * sizeof(ptr); 1394 return string(buf, end, "pK-error", spec); 1395 } 1396 1397 /* 1398 * Only print the real pointer value if the current 1399 * process has CAP_SYSLOG and is running with the 1400 * same credentials it started with. This is because 1401 * access to files is checked at open() time, but %pK 1402 * checks permission at read() time. We don't want to 1403 * leak pointer values if a binary opens a file using 1404 * %pK and then elevates privileges before reading it. 1405 */ 1406 cred = current_cred(); 1407 if (!has_capability_noaudit(current, CAP_SYSLOG) || 1408 !uid_eq(cred->euid, cred->uid) || 1409 !gid_eq(cred->egid, cred->gid)) 1410 ptr = NULL; 1411 break; 1412 } 1413 case 2: 1414 default: 1415 /* Always print 0's for %pK */ 1416 ptr = NULL; 1417 break; 1418 } 1419 1420 return pointer_string(buf, end, ptr, spec); 1421 } 1422 1423 static noinline_for_stack 1424 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt) 1425 { 1426 unsigned long long num; 1427 int size; 1428 1429 switch (fmt[1]) { 1430 case 'F': 1431 num = *(const netdev_features_t *)addr; 1432 size = sizeof(netdev_features_t); 1433 break; 1434 default: 1435 num = (unsigned long)addr; 1436 size = sizeof(unsigned long); 1437 break; 1438 } 1439 1440 return special_hex_number(buf, end, num, size); 1441 } 1442 1443 static noinline_for_stack 1444 char *address_val(char *buf, char *end, const void *addr, const char *fmt) 1445 { 1446 unsigned long long num; 1447 int size; 1448 1449 switch (fmt[1]) { 1450 case 'd': 1451 num = *(const dma_addr_t *)addr; 1452 size = sizeof(dma_addr_t); 1453 break; 1454 case 'p': 1455 default: 1456 num = *(const phys_addr_t *)addr; 1457 size = sizeof(phys_addr_t); 1458 break; 1459 } 1460 1461 return special_hex_number(buf, end, num, size); 1462 } 1463 1464 static noinline_for_stack 1465 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1466 const char *fmt) 1467 { 1468 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk) 1469 return string(buf, end, NULL, spec); 1470 1471 switch (fmt[1]) { 1472 case 'n': 1473 default: 1474 #ifdef CONFIG_COMMON_CLK 1475 return string(buf, end, __clk_get_name(clk), spec); 1476 #else 1477 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long)); 1478 #endif 1479 } 1480 } 1481 1482 static 1483 char *format_flags(char *buf, char *end, unsigned long flags, 1484 const struct trace_print_flags *names) 1485 { 1486 unsigned long mask; 1487 1488 for ( ; flags && names->name; names++) { 1489 mask = names->mask; 1490 if ((flags & mask) != mask) 1491 continue; 1492 1493 buf = string(buf, end, names->name, default_str_spec); 1494 1495 flags &= ~mask; 1496 if (flags) { 1497 if (buf < end) 1498 *buf = '|'; 1499 buf++; 1500 } 1501 } 1502 1503 if (flags) 1504 buf = number(buf, end, flags, default_flag_spec); 1505 1506 return buf; 1507 } 1508 1509 static noinline_for_stack 1510 char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt) 1511 { 1512 unsigned long flags; 1513 const struct trace_print_flags *names; 1514 1515 switch (fmt[1]) { 1516 case 'p': 1517 flags = *(unsigned long *)flags_ptr; 1518 /* Remove zone id */ 1519 flags &= (1UL << NR_PAGEFLAGS) - 1; 1520 names = pageflag_names; 1521 break; 1522 case 'v': 1523 flags = *(unsigned long *)flags_ptr; 1524 names = vmaflag_names; 1525 break; 1526 case 'g': 1527 flags = *(gfp_t *)flags_ptr; 1528 names = gfpflag_names; 1529 break; 1530 default: 1531 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]); 1532 return buf; 1533 } 1534 1535 return format_flags(buf, end, flags, names); 1536 } 1537 1538 static const char *device_node_name_for_depth(const struct device_node *np, int depth) 1539 { 1540 for ( ; np && depth; depth--) 1541 np = np->parent; 1542 1543 return kbasename(np->full_name); 1544 } 1545 1546 static noinline_for_stack 1547 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end) 1548 { 1549 int depth; 1550 const struct device_node *parent = np->parent; 1551 1552 /* special case for root node */ 1553 if (!parent) 1554 return string(buf, end, "/", default_str_spec); 1555 1556 for (depth = 0; parent->parent; depth++) 1557 parent = parent->parent; 1558 1559 for ( ; depth >= 0; depth--) { 1560 buf = string(buf, end, "/", default_str_spec); 1561 buf = string(buf, end, device_node_name_for_depth(np, depth), 1562 default_str_spec); 1563 } 1564 return buf; 1565 } 1566 1567 static noinline_for_stack 1568 char *device_node_string(char *buf, char *end, struct device_node *dn, 1569 struct printf_spec spec, const char *fmt) 1570 { 1571 char tbuf[sizeof("xxxx") + 1]; 1572 const char *p; 1573 int ret; 1574 char *buf_start = buf; 1575 struct property *prop; 1576 bool has_mult, pass; 1577 static const struct printf_spec num_spec = { 1578 .flags = SMALL, 1579 .field_width = -1, 1580 .precision = -1, 1581 .base = 10, 1582 }; 1583 1584 struct printf_spec str_spec = spec; 1585 str_spec.field_width = -1; 1586 1587 if (!IS_ENABLED(CONFIG_OF)) 1588 return string(buf, end, "(!OF)", spec); 1589 1590 if ((unsigned long)dn < PAGE_SIZE) 1591 return string(buf, end, "(null)", spec); 1592 1593 /* simple case without anything any more format specifiers */ 1594 fmt++; 1595 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 1596 fmt = "f"; 1597 1598 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 1599 if (pass) { 1600 if (buf < end) 1601 *buf = ':'; 1602 buf++; 1603 } 1604 1605 switch (*fmt) { 1606 case 'f': /* full_name */ 1607 buf = device_node_gen_full_name(dn, buf, end); 1608 break; 1609 case 'n': /* name */ 1610 buf = string(buf, end, dn->name, str_spec); 1611 break; 1612 case 'p': /* phandle */ 1613 buf = number(buf, end, (unsigned int)dn->phandle, num_spec); 1614 break; 1615 case 'P': /* path-spec */ 1616 p = kbasename(of_node_full_name(dn)); 1617 if (!p[1]) 1618 p = "/"; 1619 buf = string(buf, end, p, str_spec); 1620 break; 1621 case 'F': /* flags */ 1622 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 1623 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 1624 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 1625 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 1626 tbuf[4] = 0; 1627 buf = string(buf, end, tbuf, str_spec); 1628 break; 1629 case 'c': /* major compatible string */ 1630 ret = of_property_read_string(dn, "compatible", &p); 1631 if (!ret) 1632 buf = string(buf, end, p, str_spec); 1633 break; 1634 case 'C': /* full compatible string */ 1635 has_mult = false; 1636 of_property_for_each_string(dn, "compatible", prop, p) { 1637 if (has_mult) 1638 buf = string(buf, end, ",", str_spec); 1639 buf = string(buf, end, "\"", str_spec); 1640 buf = string(buf, end, p, str_spec); 1641 buf = string(buf, end, "\"", str_spec); 1642 1643 has_mult = true; 1644 } 1645 break; 1646 default: 1647 break; 1648 } 1649 } 1650 1651 return widen_string(buf, buf - buf_start, end, spec); 1652 } 1653 1654 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key); 1655 static siphash_key_t ptr_key __read_mostly; 1656 1657 static void enable_ptr_key_workfn(struct work_struct *work) 1658 { 1659 get_random_bytes(&ptr_key, sizeof(ptr_key)); 1660 /* Needs to run from preemptible context */ 1661 static_branch_disable(¬_filled_random_ptr_key); 1662 } 1663 1664 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); 1665 1666 static void fill_random_ptr_key(struct random_ready_callback *unused) 1667 { 1668 /* This may be in an interrupt handler. */ 1669 queue_work(system_unbound_wq, &enable_ptr_key_work); 1670 } 1671 1672 static struct random_ready_callback random_ready = { 1673 .func = fill_random_ptr_key 1674 }; 1675 1676 static int __init initialize_ptr_random(void) 1677 { 1678 int ret = add_random_ready_callback(&random_ready); 1679 1680 if (!ret) { 1681 return 0; 1682 } else if (ret == -EALREADY) { 1683 /* This is in preemptible context */ 1684 enable_ptr_key_workfn(&enable_ptr_key_work); 1685 return 0; 1686 } 1687 1688 return ret; 1689 } 1690 early_initcall(initialize_ptr_random); 1691 1692 /* Maps a pointer to a 32 bit unique identifier. */ 1693 static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec) 1694 { 1695 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 1696 unsigned long hashval; 1697 1698 if (static_branch_unlikely(¬_filled_random_ptr_key)) { 1699 spec.field_width = 2 * sizeof(ptr); 1700 /* string length must be less than default_width */ 1701 return string(buf, end, str, spec); 1702 } 1703 1704 #ifdef CONFIG_64BIT 1705 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 1706 /* 1707 * Mask off the first 32 bits, this makes explicit that we have 1708 * modified the address (and 32 bits is plenty for a unique ID). 1709 */ 1710 hashval = hashval & 0xffffffff; 1711 #else 1712 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 1713 #endif 1714 return pointer_string(buf, end, (const void *)hashval, spec); 1715 } 1716 1717 /* 1718 * Show a '%p' thing. A kernel extension is that the '%p' is followed 1719 * by an extra set of alphanumeric characters that are extended format 1720 * specifiers. 1721 * 1722 * Please update scripts/checkpatch.pl when adding/removing conversion 1723 * characters. (Search for "check for vsprintf extension"). 1724 * 1725 * Right now we handle: 1726 * 1727 * - 'S' For symbolic direct pointers (or function descriptors) with offset 1728 * - 's' For symbolic direct pointers (or function descriptors) without offset 1729 * - 'F' Same as 'S' 1730 * - 'f' Same as 's' 1731 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation 1732 * - 'B' For backtraced symbolic direct pointers with offset 1733 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 1734 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 1735 * - 'b[l]' For a bitmap, the number of bits is determined by the field 1736 * width which must be explicitly specified either as part of the 1737 * format string '%32b[l]' or through '%*b[l]', [l] selects 1738 * range-list format instead of hex format 1739 * - 'M' For a 6-byte MAC address, it prints the address in the 1740 * usual colon-separated hex notation 1741 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 1742 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 1743 * with a dash-separated hex notation 1744 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 1745 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 1746 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 1747 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 1748 * [S][pfs] 1749 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 1750 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 1751 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 1752 * IPv6 omits the colons (01020304...0f) 1753 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 1754 * [S][pfs] 1755 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 1756 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 1757 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 1758 * - 'I[6S]c' for IPv6 addresses printed as specified by 1759 * http://tools.ietf.org/html/rfc5952 1760 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 1761 * of the following flags (see string_escape_mem() for the 1762 * details): 1763 * a - ESCAPE_ANY 1764 * c - ESCAPE_SPECIAL 1765 * h - ESCAPE_HEX 1766 * n - ESCAPE_NULL 1767 * o - ESCAPE_OCTAL 1768 * p - ESCAPE_NP 1769 * s - ESCAPE_SPACE 1770 * By default ESCAPE_ANY_NP is used. 1771 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 1772 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 1773 * Options for %pU are: 1774 * b big endian lower case hex (default) 1775 * B big endian UPPER case hex 1776 * l little endian lower case hex 1777 * L little endian UPPER case hex 1778 * big endian output byte order is: 1779 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 1780 * little endian output byte order is: 1781 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 1782 * - 'V' For a struct va_format which contains a format string * and va_list *, 1783 * call vsnprintf(->format, *->va_list). 1784 * Implements a "recursive vsnprintf". 1785 * Do not use this feature without some mechanism to verify the 1786 * correctness of the format string and va_list arguments. 1787 * - 'K' For a kernel pointer that should be hidden from unprivileged users 1788 * - 'NF' For a netdev_features_t 1789 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 1790 * a certain separator (' ' by default): 1791 * C colon 1792 * D dash 1793 * N no separator 1794 * The maximum supported length is 64 bytes of the input. Consider 1795 * to use print_hex_dump() for the larger input. 1796 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 1797 * (default assumed to be phys_addr_t, passed by reference) 1798 * - 'd[234]' For a dentry name (optionally 2-4 last components) 1799 * - 'D[234]' Same as 'd' but for a struct file 1800 * - 'g' For block_device name (gendisk + partition number) 1801 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 1802 * (legacy clock framework) of the clock 1803 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 1804 * (legacy clock framework) of the clock 1805 * - 'Cr' For a clock, it prints the current rate of the clock 1806 * - 'G' For flags to be printed as a collection of symbolic strings that would 1807 * construct the specific value. Supported flags given by option: 1808 * p page flags (see struct page) given as pointer to unsigned long 1809 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 1810 * v vma flags (VM_*) given as pointer to unsigned long 1811 * - 'O' For a kobject based struct. Must be one of the following: 1812 * - 'OF[fnpPcCF]' For a device tree object 1813 * Without any optional arguments prints the full_name 1814 * f device node full_name 1815 * n device node name 1816 * p device node phandle 1817 * P device node path spec (name + @unit) 1818 * F device node flags 1819 * c major compatible string 1820 * C full compatible string 1821 * 1822 * - 'x' For printing the address. Equivalent to "%lx". 1823 * 1824 * ** When making changes please also update: 1825 * Documentation/core-api/printk-formats.rst 1826 * 1827 * Note: The default behaviour (unadorned %p) is to hash the address, 1828 * rendering it useful as a unique identifier. 1829 */ 1830 static noinline_for_stack 1831 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 1832 struct printf_spec spec) 1833 { 1834 const int default_width = 2 * sizeof(void *); 1835 1836 if (!ptr && *fmt != 'K' && *fmt != 'x') { 1837 /* 1838 * Print (null) with the same width as a pointer so it makes 1839 * tabular output look nice. 1840 */ 1841 if (spec.field_width == -1) 1842 spec.field_width = default_width; 1843 return string(buf, end, "(null)", spec); 1844 } 1845 1846 switch (*fmt) { 1847 case 'F': 1848 case 'f': 1849 case 'S': 1850 case 's': 1851 ptr = dereference_symbol_descriptor(ptr); 1852 /* Fallthrough */ 1853 case 'B': 1854 return symbol_string(buf, end, ptr, spec, fmt); 1855 case 'R': 1856 case 'r': 1857 return resource_string(buf, end, ptr, spec, fmt); 1858 case 'h': 1859 return hex_string(buf, end, ptr, spec, fmt); 1860 case 'b': 1861 switch (fmt[1]) { 1862 case 'l': 1863 return bitmap_list_string(buf, end, ptr, spec, fmt); 1864 default: 1865 return bitmap_string(buf, end, ptr, spec, fmt); 1866 } 1867 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 1868 case 'm': /* Contiguous: 000102030405 */ 1869 /* [mM]F (FDDI) */ 1870 /* [mM]R (Reverse order; Bluetooth) */ 1871 return mac_address_string(buf, end, ptr, spec, fmt); 1872 case 'I': /* Formatted IP supported 1873 * 4: 1.2.3.4 1874 * 6: 0001:0203:...:0708 1875 * 6c: 1::708 or 1::1.2.3.4 1876 */ 1877 case 'i': /* Contiguous: 1878 * 4: 001.002.003.004 1879 * 6: 000102...0f 1880 */ 1881 switch (fmt[1]) { 1882 case '6': 1883 return ip6_addr_string(buf, end, ptr, spec, fmt); 1884 case '4': 1885 return ip4_addr_string(buf, end, ptr, spec, fmt); 1886 case 'S': { 1887 const union { 1888 struct sockaddr raw; 1889 struct sockaddr_in v4; 1890 struct sockaddr_in6 v6; 1891 } *sa = ptr; 1892 1893 switch (sa->raw.sa_family) { 1894 case AF_INET: 1895 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1896 case AF_INET6: 1897 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1898 default: 1899 return string(buf, end, "(invalid address)", spec); 1900 }} 1901 } 1902 break; 1903 case 'E': 1904 return escaped_string(buf, end, ptr, spec, fmt); 1905 case 'U': 1906 return uuid_string(buf, end, ptr, spec, fmt); 1907 case 'V': 1908 { 1909 va_list va; 1910 1911 va_copy(va, *((struct va_format *)ptr)->va); 1912 buf += vsnprintf(buf, end > buf ? end - buf : 0, 1913 ((struct va_format *)ptr)->fmt, va); 1914 va_end(va); 1915 return buf; 1916 } 1917 case 'K': 1918 if (!kptr_restrict) 1919 break; 1920 return restricted_pointer(buf, end, ptr, spec); 1921 case 'N': 1922 return netdev_bits(buf, end, ptr, fmt); 1923 case 'a': 1924 return address_val(buf, end, ptr, fmt); 1925 case 'd': 1926 return dentry_name(buf, end, ptr, spec, fmt); 1927 case 'C': 1928 return clock(buf, end, ptr, spec, fmt); 1929 case 'D': 1930 return dentry_name(buf, end, 1931 ((const struct file *)ptr)->f_path.dentry, 1932 spec, fmt); 1933 #ifdef CONFIG_BLOCK 1934 case 'g': 1935 return bdev_name(buf, end, ptr, spec, fmt); 1936 #endif 1937 1938 case 'G': 1939 return flags_string(buf, end, ptr, fmt); 1940 case 'O': 1941 switch (fmt[1]) { 1942 case 'F': 1943 return device_node_string(buf, end, ptr, spec, fmt + 1); 1944 } 1945 case 'x': 1946 return pointer_string(buf, end, ptr, spec); 1947 } 1948 1949 /* default is to _not_ leak addresses, hash before printing */ 1950 return ptr_to_id(buf, end, ptr, spec); 1951 } 1952 1953 /* 1954 * Helper function to decode printf style format. 1955 * Each call decode a token from the format and return the 1956 * number of characters read (or likely the delta where it wants 1957 * to go on the next call). 1958 * The decoded token is returned through the parameters 1959 * 1960 * 'h', 'l', or 'L' for integer fields 1961 * 'z' support added 23/7/1999 S.H. 1962 * 'z' changed to 'Z' --davidm 1/25/99 1963 * 'Z' changed to 'z' --adobriyan 2017-01-25 1964 * 't' added for ptrdiff_t 1965 * 1966 * @fmt: the format string 1967 * @type of the token returned 1968 * @flags: various flags such as +, -, # tokens.. 1969 * @field_width: overwritten width 1970 * @base: base of the number (octal, hex, ...) 1971 * @precision: precision of a number 1972 * @qualifier: qualifier of a number (long, size_t, ...) 1973 */ 1974 static noinline_for_stack 1975 int format_decode(const char *fmt, struct printf_spec *spec) 1976 { 1977 const char *start = fmt; 1978 char qualifier; 1979 1980 /* we finished early by reading the field width */ 1981 if (spec->type == FORMAT_TYPE_WIDTH) { 1982 if (spec->field_width < 0) { 1983 spec->field_width = -spec->field_width; 1984 spec->flags |= LEFT; 1985 } 1986 spec->type = FORMAT_TYPE_NONE; 1987 goto precision; 1988 } 1989 1990 /* we finished early by reading the precision */ 1991 if (spec->type == FORMAT_TYPE_PRECISION) { 1992 if (spec->precision < 0) 1993 spec->precision = 0; 1994 1995 spec->type = FORMAT_TYPE_NONE; 1996 goto qualifier; 1997 } 1998 1999 /* By default */ 2000 spec->type = FORMAT_TYPE_NONE; 2001 2002 for (; *fmt ; ++fmt) { 2003 if (*fmt == '%') 2004 break; 2005 } 2006 2007 /* Return the current non-format string */ 2008 if (fmt != start || !*fmt) 2009 return fmt - start; 2010 2011 /* Process flags */ 2012 spec->flags = 0; 2013 2014 while (1) { /* this also skips first '%' */ 2015 bool found = true; 2016 2017 ++fmt; 2018 2019 switch (*fmt) { 2020 case '-': spec->flags |= LEFT; break; 2021 case '+': spec->flags |= PLUS; break; 2022 case ' ': spec->flags |= SPACE; break; 2023 case '#': spec->flags |= SPECIAL; break; 2024 case '0': spec->flags |= ZEROPAD; break; 2025 default: found = false; 2026 } 2027 2028 if (!found) 2029 break; 2030 } 2031 2032 /* get field width */ 2033 spec->field_width = -1; 2034 2035 if (isdigit(*fmt)) 2036 spec->field_width = skip_atoi(&fmt); 2037 else if (*fmt == '*') { 2038 /* it's the next argument */ 2039 spec->type = FORMAT_TYPE_WIDTH; 2040 return ++fmt - start; 2041 } 2042 2043 precision: 2044 /* get the precision */ 2045 spec->precision = -1; 2046 if (*fmt == '.') { 2047 ++fmt; 2048 if (isdigit(*fmt)) { 2049 spec->precision = skip_atoi(&fmt); 2050 if (spec->precision < 0) 2051 spec->precision = 0; 2052 } else if (*fmt == '*') { 2053 /* it's the next argument */ 2054 spec->type = FORMAT_TYPE_PRECISION; 2055 return ++fmt - start; 2056 } 2057 } 2058 2059 qualifier: 2060 /* get the conversion qualifier */ 2061 qualifier = 0; 2062 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2063 *fmt == 'z' || *fmt == 't') { 2064 qualifier = *fmt++; 2065 if (unlikely(qualifier == *fmt)) { 2066 if (qualifier == 'l') { 2067 qualifier = 'L'; 2068 ++fmt; 2069 } else if (qualifier == 'h') { 2070 qualifier = 'H'; 2071 ++fmt; 2072 } 2073 } 2074 } 2075 2076 /* default base */ 2077 spec->base = 10; 2078 switch (*fmt) { 2079 case 'c': 2080 spec->type = FORMAT_TYPE_CHAR; 2081 return ++fmt - start; 2082 2083 case 's': 2084 spec->type = FORMAT_TYPE_STR; 2085 return ++fmt - start; 2086 2087 case 'p': 2088 spec->type = FORMAT_TYPE_PTR; 2089 return ++fmt - start; 2090 2091 case '%': 2092 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2093 return ++fmt - start; 2094 2095 /* integer number formats - set up the flags and "break" */ 2096 case 'o': 2097 spec->base = 8; 2098 break; 2099 2100 case 'x': 2101 spec->flags |= SMALL; 2102 /* fall through */ 2103 2104 case 'X': 2105 spec->base = 16; 2106 break; 2107 2108 case 'd': 2109 case 'i': 2110 spec->flags |= SIGN; 2111 case 'u': 2112 break; 2113 2114 case 'n': 2115 /* 2116 * Since %n poses a greater security risk than 2117 * utility, treat it as any other invalid or 2118 * unsupported format specifier. 2119 */ 2120 /* Fall-through */ 2121 2122 default: 2123 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2124 spec->type = FORMAT_TYPE_INVALID; 2125 return fmt - start; 2126 } 2127 2128 if (qualifier == 'L') 2129 spec->type = FORMAT_TYPE_LONG_LONG; 2130 else if (qualifier == 'l') { 2131 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2132 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2133 } else if (qualifier == 'z') { 2134 spec->type = FORMAT_TYPE_SIZE_T; 2135 } else if (qualifier == 't') { 2136 spec->type = FORMAT_TYPE_PTRDIFF; 2137 } else if (qualifier == 'H') { 2138 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2139 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2140 } else if (qualifier == 'h') { 2141 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2142 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2143 } else { 2144 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2145 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2146 } 2147 2148 return ++fmt - start; 2149 } 2150 2151 static void 2152 set_field_width(struct printf_spec *spec, int width) 2153 { 2154 spec->field_width = width; 2155 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2156 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2157 } 2158 } 2159 2160 static void 2161 set_precision(struct printf_spec *spec, int prec) 2162 { 2163 spec->precision = prec; 2164 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2165 spec->precision = clamp(prec, 0, PRECISION_MAX); 2166 } 2167 } 2168 2169 /** 2170 * vsnprintf - Format a string and place it in a buffer 2171 * @buf: The buffer to place the result into 2172 * @size: The size of the buffer, including the trailing null space 2173 * @fmt: The format string to use 2174 * @args: Arguments for the format string 2175 * 2176 * This function generally follows C99 vsnprintf, but has some 2177 * extensions and a few limitations: 2178 * 2179 * - ``%n`` is unsupported 2180 * - ``%p*`` is handled by pointer() 2181 * 2182 * See pointer() or Documentation/core-api/printk-formats.rst for more 2183 * extensive description. 2184 * 2185 * **Please update the documentation in both places when making changes** 2186 * 2187 * The return value is the number of characters which would 2188 * be generated for the given input, excluding the trailing 2189 * '\0', as per ISO C99. If you want to have the exact 2190 * number of characters written into @buf as return value 2191 * (not including the trailing '\0'), use vscnprintf(). If the 2192 * return is greater than or equal to @size, the resulting 2193 * string is truncated. 2194 * 2195 * If you're not already dealing with a va_list consider using snprintf(). 2196 */ 2197 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2198 { 2199 unsigned long long num; 2200 char *str, *end; 2201 struct printf_spec spec = {0}; 2202 2203 /* Reject out-of-range values early. Large positive sizes are 2204 used for unknown buffer sizes. */ 2205 if (WARN_ON_ONCE(size > INT_MAX)) 2206 return 0; 2207 2208 str = buf; 2209 end = buf + size; 2210 2211 /* Make sure end is always >= buf */ 2212 if (end < buf) { 2213 end = ((void *)-1); 2214 size = end - buf; 2215 } 2216 2217 while (*fmt) { 2218 const char *old_fmt = fmt; 2219 int read = format_decode(fmt, &spec); 2220 2221 fmt += read; 2222 2223 switch (spec.type) { 2224 case FORMAT_TYPE_NONE: { 2225 int copy = read; 2226 if (str < end) { 2227 if (copy > end - str) 2228 copy = end - str; 2229 memcpy(str, old_fmt, copy); 2230 } 2231 str += read; 2232 break; 2233 } 2234 2235 case FORMAT_TYPE_WIDTH: 2236 set_field_width(&spec, va_arg(args, int)); 2237 break; 2238 2239 case FORMAT_TYPE_PRECISION: 2240 set_precision(&spec, va_arg(args, int)); 2241 break; 2242 2243 case FORMAT_TYPE_CHAR: { 2244 char c; 2245 2246 if (!(spec.flags & LEFT)) { 2247 while (--spec.field_width > 0) { 2248 if (str < end) 2249 *str = ' '; 2250 ++str; 2251 2252 } 2253 } 2254 c = (unsigned char) va_arg(args, int); 2255 if (str < end) 2256 *str = c; 2257 ++str; 2258 while (--spec.field_width > 0) { 2259 if (str < end) 2260 *str = ' '; 2261 ++str; 2262 } 2263 break; 2264 } 2265 2266 case FORMAT_TYPE_STR: 2267 str = string(str, end, va_arg(args, char *), spec); 2268 break; 2269 2270 case FORMAT_TYPE_PTR: 2271 str = pointer(fmt, str, end, va_arg(args, void *), 2272 spec); 2273 while (isalnum(*fmt)) 2274 fmt++; 2275 break; 2276 2277 case FORMAT_TYPE_PERCENT_CHAR: 2278 if (str < end) 2279 *str = '%'; 2280 ++str; 2281 break; 2282 2283 case FORMAT_TYPE_INVALID: 2284 /* 2285 * Presumably the arguments passed gcc's type 2286 * checking, but there is no safe or sane way 2287 * for us to continue parsing the format and 2288 * fetching from the va_list; the remaining 2289 * specifiers and arguments would be out of 2290 * sync. 2291 */ 2292 goto out; 2293 2294 default: 2295 switch (spec.type) { 2296 case FORMAT_TYPE_LONG_LONG: 2297 num = va_arg(args, long long); 2298 break; 2299 case FORMAT_TYPE_ULONG: 2300 num = va_arg(args, unsigned long); 2301 break; 2302 case FORMAT_TYPE_LONG: 2303 num = va_arg(args, long); 2304 break; 2305 case FORMAT_TYPE_SIZE_T: 2306 if (spec.flags & SIGN) 2307 num = va_arg(args, ssize_t); 2308 else 2309 num = va_arg(args, size_t); 2310 break; 2311 case FORMAT_TYPE_PTRDIFF: 2312 num = va_arg(args, ptrdiff_t); 2313 break; 2314 case FORMAT_TYPE_UBYTE: 2315 num = (unsigned char) va_arg(args, int); 2316 break; 2317 case FORMAT_TYPE_BYTE: 2318 num = (signed char) va_arg(args, int); 2319 break; 2320 case FORMAT_TYPE_USHORT: 2321 num = (unsigned short) va_arg(args, int); 2322 break; 2323 case FORMAT_TYPE_SHORT: 2324 num = (short) va_arg(args, int); 2325 break; 2326 case FORMAT_TYPE_INT: 2327 num = (int) va_arg(args, int); 2328 break; 2329 default: 2330 num = va_arg(args, unsigned int); 2331 } 2332 2333 str = number(str, end, num, spec); 2334 } 2335 } 2336 2337 out: 2338 if (size > 0) { 2339 if (str < end) 2340 *str = '\0'; 2341 else 2342 end[-1] = '\0'; 2343 } 2344 2345 /* the trailing null byte doesn't count towards the total */ 2346 return str-buf; 2347 2348 } 2349 EXPORT_SYMBOL(vsnprintf); 2350 2351 /** 2352 * vscnprintf - Format a string and place it in a buffer 2353 * @buf: The buffer to place the result into 2354 * @size: The size of the buffer, including the trailing null space 2355 * @fmt: The format string to use 2356 * @args: Arguments for the format string 2357 * 2358 * The return value is the number of characters which have been written into 2359 * the @buf not including the trailing '\0'. If @size is == 0 the function 2360 * returns 0. 2361 * 2362 * If you're not already dealing with a va_list consider using scnprintf(). 2363 * 2364 * See the vsnprintf() documentation for format string extensions over C99. 2365 */ 2366 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2367 { 2368 int i; 2369 2370 i = vsnprintf(buf, size, fmt, args); 2371 2372 if (likely(i < size)) 2373 return i; 2374 if (size != 0) 2375 return size - 1; 2376 return 0; 2377 } 2378 EXPORT_SYMBOL(vscnprintf); 2379 2380 /** 2381 * snprintf - Format a string and place it in a buffer 2382 * @buf: The buffer to place the result into 2383 * @size: The size of the buffer, including the trailing null space 2384 * @fmt: The format string to use 2385 * @...: Arguments for the format string 2386 * 2387 * The return value is the number of characters which would be 2388 * generated for the given input, excluding the trailing null, 2389 * as per ISO C99. If the return is greater than or equal to 2390 * @size, the resulting string is truncated. 2391 * 2392 * See the vsnprintf() documentation for format string extensions over C99. 2393 */ 2394 int snprintf(char *buf, size_t size, const char *fmt, ...) 2395 { 2396 va_list args; 2397 int i; 2398 2399 va_start(args, fmt); 2400 i = vsnprintf(buf, size, fmt, args); 2401 va_end(args); 2402 2403 return i; 2404 } 2405 EXPORT_SYMBOL(snprintf); 2406 2407 /** 2408 * scnprintf - Format a string and place it in a buffer 2409 * @buf: The buffer to place the result into 2410 * @size: The size of the buffer, including the trailing null space 2411 * @fmt: The format string to use 2412 * @...: Arguments for the format string 2413 * 2414 * The return value is the number of characters written into @buf not including 2415 * the trailing '\0'. If @size is == 0 the function returns 0. 2416 */ 2417 2418 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2419 { 2420 va_list args; 2421 int i; 2422 2423 va_start(args, fmt); 2424 i = vscnprintf(buf, size, fmt, args); 2425 va_end(args); 2426 2427 return i; 2428 } 2429 EXPORT_SYMBOL(scnprintf); 2430 2431 /** 2432 * vsprintf - Format a string and place it in a buffer 2433 * @buf: The buffer to place the result into 2434 * @fmt: The format string to use 2435 * @args: Arguments for the format string 2436 * 2437 * The function returns the number of characters written 2438 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2439 * buffer overflows. 2440 * 2441 * If you're not already dealing with a va_list consider using sprintf(). 2442 * 2443 * See the vsnprintf() documentation for format string extensions over C99. 2444 */ 2445 int vsprintf(char *buf, const char *fmt, va_list args) 2446 { 2447 return vsnprintf(buf, INT_MAX, fmt, args); 2448 } 2449 EXPORT_SYMBOL(vsprintf); 2450 2451 /** 2452 * sprintf - Format a string and place it in a buffer 2453 * @buf: The buffer to place the result into 2454 * @fmt: The format string to use 2455 * @...: Arguments for the format string 2456 * 2457 * The function returns the number of characters written 2458 * into @buf. Use snprintf() or scnprintf() in order to avoid 2459 * buffer overflows. 2460 * 2461 * See the vsnprintf() documentation for format string extensions over C99. 2462 */ 2463 int sprintf(char *buf, const char *fmt, ...) 2464 { 2465 va_list args; 2466 int i; 2467 2468 va_start(args, fmt); 2469 i = vsnprintf(buf, INT_MAX, fmt, args); 2470 va_end(args); 2471 2472 return i; 2473 } 2474 EXPORT_SYMBOL(sprintf); 2475 2476 #ifdef CONFIG_BINARY_PRINTF 2477 /* 2478 * bprintf service: 2479 * vbin_printf() - VA arguments to binary data 2480 * bstr_printf() - Binary data to text string 2481 */ 2482 2483 /** 2484 * vbin_printf - Parse a format string and place args' binary value in a buffer 2485 * @bin_buf: The buffer to place args' binary value 2486 * @size: The size of the buffer(by words(32bits), not characters) 2487 * @fmt: The format string to use 2488 * @args: Arguments for the format string 2489 * 2490 * The format follows C99 vsnprintf, except %n is ignored, and its argument 2491 * is skipped. 2492 * 2493 * The return value is the number of words(32bits) which would be generated for 2494 * the given input. 2495 * 2496 * NOTE: 2497 * If the return value is greater than @size, the resulting bin_buf is NOT 2498 * valid for bstr_printf(). 2499 */ 2500 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 2501 { 2502 struct printf_spec spec = {0}; 2503 char *str, *end; 2504 int width; 2505 2506 str = (char *)bin_buf; 2507 end = (char *)(bin_buf + size); 2508 2509 #define save_arg(type) \ 2510 ({ \ 2511 unsigned long long value; \ 2512 if (sizeof(type) == 8) { \ 2513 unsigned long long val8; \ 2514 str = PTR_ALIGN(str, sizeof(u32)); \ 2515 val8 = va_arg(args, unsigned long long); \ 2516 if (str + sizeof(type) <= end) { \ 2517 *(u32 *)str = *(u32 *)&val8; \ 2518 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 2519 } \ 2520 value = val8; \ 2521 } else { \ 2522 unsigned int val4; \ 2523 str = PTR_ALIGN(str, sizeof(type)); \ 2524 val4 = va_arg(args, int); \ 2525 if (str + sizeof(type) <= end) \ 2526 *(typeof(type) *)str = (type)(long)val4; \ 2527 value = (unsigned long long)val4; \ 2528 } \ 2529 str += sizeof(type); \ 2530 value; \ 2531 }) 2532 2533 while (*fmt) { 2534 int read = format_decode(fmt, &spec); 2535 2536 fmt += read; 2537 2538 switch (spec.type) { 2539 case FORMAT_TYPE_NONE: 2540 case FORMAT_TYPE_PERCENT_CHAR: 2541 break; 2542 case FORMAT_TYPE_INVALID: 2543 goto out; 2544 2545 case FORMAT_TYPE_WIDTH: 2546 case FORMAT_TYPE_PRECISION: 2547 width = (int)save_arg(int); 2548 /* Pointers may require the width */ 2549 if (*fmt == 'p') 2550 set_field_width(&spec, width); 2551 break; 2552 2553 case FORMAT_TYPE_CHAR: 2554 save_arg(char); 2555 break; 2556 2557 case FORMAT_TYPE_STR: { 2558 const char *save_str = va_arg(args, char *); 2559 size_t len; 2560 2561 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 2562 || (unsigned long)save_str < PAGE_SIZE) 2563 save_str = "(null)"; 2564 len = strlen(save_str) + 1; 2565 if (str + len < end) 2566 memcpy(str, save_str, len); 2567 str += len; 2568 break; 2569 } 2570 2571 case FORMAT_TYPE_PTR: 2572 /* Dereferenced pointers must be done now */ 2573 switch (*fmt) { 2574 /* Dereference of functions is still OK */ 2575 case 'S': 2576 case 's': 2577 case 'F': 2578 case 'f': 2579 case 'x': 2580 case 'K': 2581 save_arg(void *); 2582 break; 2583 default: 2584 if (!isalnum(*fmt)) { 2585 save_arg(void *); 2586 break; 2587 } 2588 str = pointer(fmt, str, end, va_arg(args, void *), 2589 spec); 2590 if (str + 1 < end) 2591 *str++ = '\0'; 2592 else 2593 end[-1] = '\0'; /* Must be nul terminated */ 2594 } 2595 /* skip all alphanumeric pointer suffixes */ 2596 while (isalnum(*fmt)) 2597 fmt++; 2598 break; 2599 2600 default: 2601 switch (spec.type) { 2602 2603 case FORMAT_TYPE_LONG_LONG: 2604 save_arg(long long); 2605 break; 2606 case FORMAT_TYPE_ULONG: 2607 case FORMAT_TYPE_LONG: 2608 save_arg(unsigned long); 2609 break; 2610 case FORMAT_TYPE_SIZE_T: 2611 save_arg(size_t); 2612 break; 2613 case FORMAT_TYPE_PTRDIFF: 2614 save_arg(ptrdiff_t); 2615 break; 2616 case FORMAT_TYPE_UBYTE: 2617 case FORMAT_TYPE_BYTE: 2618 save_arg(char); 2619 break; 2620 case FORMAT_TYPE_USHORT: 2621 case FORMAT_TYPE_SHORT: 2622 save_arg(short); 2623 break; 2624 default: 2625 save_arg(int); 2626 } 2627 } 2628 } 2629 2630 out: 2631 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 2632 #undef save_arg 2633 } 2634 EXPORT_SYMBOL_GPL(vbin_printf); 2635 2636 /** 2637 * bstr_printf - Format a string from binary arguments and place it in a buffer 2638 * @buf: The buffer to place the result into 2639 * @size: The size of the buffer, including the trailing null space 2640 * @fmt: The format string to use 2641 * @bin_buf: Binary arguments for the format string 2642 * 2643 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 2644 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 2645 * a binary buffer that generated by vbin_printf. 2646 * 2647 * The format follows C99 vsnprintf, but has some extensions: 2648 * see vsnprintf comment for details. 2649 * 2650 * The return value is the number of characters which would 2651 * be generated for the given input, excluding the trailing 2652 * '\0', as per ISO C99. If you want to have the exact 2653 * number of characters written into @buf as return value 2654 * (not including the trailing '\0'), use vscnprintf(). If the 2655 * return is greater than or equal to @size, the resulting 2656 * string is truncated. 2657 */ 2658 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 2659 { 2660 struct printf_spec spec = {0}; 2661 char *str, *end; 2662 const char *args = (const char *)bin_buf; 2663 2664 if (WARN_ON_ONCE(size > INT_MAX)) 2665 return 0; 2666 2667 str = buf; 2668 end = buf + size; 2669 2670 #define get_arg(type) \ 2671 ({ \ 2672 typeof(type) value; \ 2673 if (sizeof(type) == 8) { \ 2674 args = PTR_ALIGN(args, sizeof(u32)); \ 2675 *(u32 *)&value = *(u32 *)args; \ 2676 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 2677 } else { \ 2678 args = PTR_ALIGN(args, sizeof(type)); \ 2679 value = *(typeof(type) *)args; \ 2680 } \ 2681 args += sizeof(type); \ 2682 value; \ 2683 }) 2684 2685 /* Make sure end is always >= buf */ 2686 if (end < buf) { 2687 end = ((void *)-1); 2688 size = end - buf; 2689 } 2690 2691 while (*fmt) { 2692 const char *old_fmt = fmt; 2693 int read = format_decode(fmt, &spec); 2694 2695 fmt += read; 2696 2697 switch (spec.type) { 2698 case FORMAT_TYPE_NONE: { 2699 int copy = read; 2700 if (str < end) { 2701 if (copy > end - str) 2702 copy = end - str; 2703 memcpy(str, old_fmt, copy); 2704 } 2705 str += read; 2706 break; 2707 } 2708 2709 case FORMAT_TYPE_WIDTH: 2710 set_field_width(&spec, get_arg(int)); 2711 break; 2712 2713 case FORMAT_TYPE_PRECISION: 2714 set_precision(&spec, get_arg(int)); 2715 break; 2716 2717 case FORMAT_TYPE_CHAR: { 2718 char c; 2719 2720 if (!(spec.flags & LEFT)) { 2721 while (--spec.field_width > 0) { 2722 if (str < end) 2723 *str = ' '; 2724 ++str; 2725 } 2726 } 2727 c = (unsigned char) get_arg(char); 2728 if (str < end) 2729 *str = c; 2730 ++str; 2731 while (--spec.field_width > 0) { 2732 if (str < end) 2733 *str = ' '; 2734 ++str; 2735 } 2736 break; 2737 } 2738 2739 case FORMAT_TYPE_STR: { 2740 const char *str_arg = args; 2741 args += strlen(str_arg) + 1; 2742 str = string(str, end, (char *)str_arg, spec); 2743 break; 2744 } 2745 2746 case FORMAT_TYPE_PTR: { 2747 bool process = false; 2748 int copy, len; 2749 /* Non function dereferences were already done */ 2750 switch (*fmt) { 2751 case 'S': 2752 case 's': 2753 case 'F': 2754 case 'f': 2755 case 'x': 2756 case 'K': 2757 process = true; 2758 break; 2759 default: 2760 if (!isalnum(*fmt)) { 2761 process = true; 2762 break; 2763 } 2764 /* Pointer dereference was already processed */ 2765 if (str < end) { 2766 len = copy = strlen(args); 2767 if (copy > end - str) 2768 copy = end - str; 2769 memcpy(str, args, copy); 2770 str += len; 2771 args += len; 2772 } 2773 } 2774 if (process) 2775 str = pointer(fmt, str, end, get_arg(void *), spec); 2776 2777 while (isalnum(*fmt)) 2778 fmt++; 2779 break; 2780 } 2781 2782 case FORMAT_TYPE_PERCENT_CHAR: 2783 if (str < end) 2784 *str = '%'; 2785 ++str; 2786 break; 2787 2788 case FORMAT_TYPE_INVALID: 2789 goto out; 2790 2791 default: { 2792 unsigned long long num; 2793 2794 switch (spec.type) { 2795 2796 case FORMAT_TYPE_LONG_LONG: 2797 num = get_arg(long long); 2798 break; 2799 case FORMAT_TYPE_ULONG: 2800 case FORMAT_TYPE_LONG: 2801 num = get_arg(unsigned long); 2802 break; 2803 case FORMAT_TYPE_SIZE_T: 2804 num = get_arg(size_t); 2805 break; 2806 case FORMAT_TYPE_PTRDIFF: 2807 num = get_arg(ptrdiff_t); 2808 break; 2809 case FORMAT_TYPE_UBYTE: 2810 num = get_arg(unsigned char); 2811 break; 2812 case FORMAT_TYPE_BYTE: 2813 num = get_arg(signed char); 2814 break; 2815 case FORMAT_TYPE_USHORT: 2816 num = get_arg(unsigned short); 2817 break; 2818 case FORMAT_TYPE_SHORT: 2819 num = get_arg(short); 2820 break; 2821 case FORMAT_TYPE_UINT: 2822 num = get_arg(unsigned int); 2823 break; 2824 default: 2825 num = get_arg(int); 2826 } 2827 2828 str = number(str, end, num, spec); 2829 } /* default: */ 2830 } /* switch(spec.type) */ 2831 } /* while(*fmt) */ 2832 2833 out: 2834 if (size > 0) { 2835 if (str < end) 2836 *str = '\0'; 2837 else 2838 end[-1] = '\0'; 2839 } 2840 2841 #undef get_arg 2842 2843 /* the trailing null byte doesn't count towards the total */ 2844 return str - buf; 2845 } 2846 EXPORT_SYMBOL_GPL(bstr_printf); 2847 2848 /** 2849 * bprintf - Parse a format string and place args' binary value in a buffer 2850 * @bin_buf: The buffer to place args' binary value 2851 * @size: The size of the buffer(by words(32bits), not characters) 2852 * @fmt: The format string to use 2853 * @...: Arguments for the format string 2854 * 2855 * The function returns the number of words(u32) written 2856 * into @bin_buf. 2857 */ 2858 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 2859 { 2860 va_list args; 2861 int ret; 2862 2863 va_start(args, fmt); 2864 ret = vbin_printf(bin_buf, size, fmt, args); 2865 va_end(args); 2866 2867 return ret; 2868 } 2869 EXPORT_SYMBOL_GPL(bprintf); 2870 2871 #endif /* CONFIG_BINARY_PRINTF */ 2872 2873 /** 2874 * vsscanf - Unformat a buffer into a list of arguments 2875 * @buf: input buffer 2876 * @fmt: format of buffer 2877 * @args: arguments 2878 */ 2879 int vsscanf(const char *buf, const char *fmt, va_list args) 2880 { 2881 const char *str = buf; 2882 char *next; 2883 char digit; 2884 int num = 0; 2885 u8 qualifier; 2886 unsigned int base; 2887 union { 2888 long long s; 2889 unsigned long long u; 2890 } val; 2891 s16 field_width; 2892 bool is_sign; 2893 2894 while (*fmt) { 2895 /* skip any white space in format */ 2896 /* white space in format matchs any amount of 2897 * white space, including none, in the input. 2898 */ 2899 if (isspace(*fmt)) { 2900 fmt = skip_spaces(++fmt); 2901 str = skip_spaces(str); 2902 } 2903 2904 /* anything that is not a conversion must match exactly */ 2905 if (*fmt != '%' && *fmt) { 2906 if (*fmt++ != *str++) 2907 break; 2908 continue; 2909 } 2910 2911 if (!*fmt) 2912 break; 2913 ++fmt; 2914 2915 /* skip this conversion. 2916 * advance both strings to next white space 2917 */ 2918 if (*fmt == '*') { 2919 if (!*str) 2920 break; 2921 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 2922 /* '%*[' not yet supported, invalid format */ 2923 if (*fmt == '[') 2924 return num; 2925 fmt++; 2926 } 2927 while (!isspace(*str) && *str) 2928 str++; 2929 continue; 2930 } 2931 2932 /* get field width */ 2933 field_width = -1; 2934 if (isdigit(*fmt)) { 2935 field_width = skip_atoi(&fmt); 2936 if (field_width <= 0) 2937 break; 2938 } 2939 2940 /* get conversion qualifier */ 2941 qualifier = -1; 2942 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2943 *fmt == 'z') { 2944 qualifier = *fmt++; 2945 if (unlikely(qualifier == *fmt)) { 2946 if (qualifier == 'h') { 2947 qualifier = 'H'; 2948 fmt++; 2949 } else if (qualifier == 'l') { 2950 qualifier = 'L'; 2951 fmt++; 2952 } 2953 } 2954 } 2955 2956 if (!*fmt) 2957 break; 2958 2959 if (*fmt == 'n') { 2960 /* return number of characters read so far */ 2961 *va_arg(args, int *) = str - buf; 2962 ++fmt; 2963 continue; 2964 } 2965 2966 if (!*str) 2967 break; 2968 2969 base = 10; 2970 is_sign = false; 2971 2972 switch (*fmt++) { 2973 case 'c': 2974 { 2975 char *s = (char *)va_arg(args, char*); 2976 if (field_width == -1) 2977 field_width = 1; 2978 do { 2979 *s++ = *str++; 2980 } while (--field_width > 0 && *str); 2981 num++; 2982 } 2983 continue; 2984 case 's': 2985 { 2986 char *s = (char *)va_arg(args, char *); 2987 if (field_width == -1) 2988 field_width = SHRT_MAX; 2989 /* first, skip leading white space in buffer */ 2990 str = skip_spaces(str); 2991 2992 /* now copy until next white space */ 2993 while (*str && !isspace(*str) && field_width--) 2994 *s++ = *str++; 2995 *s = '\0'; 2996 num++; 2997 } 2998 continue; 2999 /* 3000 * Warning: This implementation of the '[' conversion specifier 3001 * deviates from its glibc counterpart in the following ways: 3002 * (1) It does NOT support ranges i.e. '-' is NOT a special 3003 * character 3004 * (2) It cannot match the closing bracket ']' itself 3005 * (3) A field width is required 3006 * (4) '%*[' (discard matching input) is currently not supported 3007 * 3008 * Example usage: 3009 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3010 * buf1, buf2, buf3); 3011 * if (ret < 3) 3012 * // etc.. 3013 */ 3014 case '[': 3015 { 3016 char *s = (char *)va_arg(args, char *); 3017 DECLARE_BITMAP(set, 256) = {0}; 3018 unsigned int len = 0; 3019 bool negate = (*fmt == '^'); 3020 3021 /* field width is required */ 3022 if (field_width == -1) 3023 return num; 3024 3025 if (negate) 3026 ++fmt; 3027 3028 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3029 set_bit((u8)*fmt, set); 3030 3031 /* no ']' or no character set found */ 3032 if (!*fmt || !len) 3033 return num; 3034 ++fmt; 3035 3036 if (negate) { 3037 bitmap_complement(set, set, 256); 3038 /* exclude null '\0' byte */ 3039 clear_bit(0, set); 3040 } 3041 3042 /* match must be non-empty */ 3043 if (!test_bit((u8)*str, set)) 3044 return num; 3045 3046 while (test_bit((u8)*str, set) && field_width--) 3047 *s++ = *str++; 3048 *s = '\0'; 3049 ++num; 3050 } 3051 continue; 3052 case 'o': 3053 base = 8; 3054 break; 3055 case 'x': 3056 case 'X': 3057 base = 16; 3058 break; 3059 case 'i': 3060 base = 0; 3061 /* fall through */ 3062 case 'd': 3063 is_sign = true; 3064 /* fall through */ 3065 case 'u': 3066 break; 3067 case '%': 3068 /* looking for '%' in str */ 3069 if (*str++ != '%') 3070 return num; 3071 continue; 3072 default: 3073 /* invalid format; stop here */ 3074 return num; 3075 } 3076 3077 /* have some sort of integer conversion. 3078 * first, skip white space in buffer. 3079 */ 3080 str = skip_spaces(str); 3081 3082 digit = *str; 3083 if (is_sign && digit == '-') 3084 digit = *(str + 1); 3085 3086 if (!digit 3087 || (base == 16 && !isxdigit(digit)) 3088 || (base == 10 && !isdigit(digit)) 3089 || (base == 8 && (!isdigit(digit) || digit > '7')) 3090 || (base == 0 && !isdigit(digit))) 3091 break; 3092 3093 if (is_sign) 3094 val.s = qualifier != 'L' ? 3095 simple_strtol(str, &next, base) : 3096 simple_strtoll(str, &next, base); 3097 else 3098 val.u = qualifier != 'L' ? 3099 simple_strtoul(str, &next, base) : 3100 simple_strtoull(str, &next, base); 3101 3102 if (field_width > 0 && next - str > field_width) { 3103 if (base == 0) 3104 _parse_integer_fixup_radix(str, &base); 3105 while (next - str > field_width) { 3106 if (is_sign) 3107 val.s = div_s64(val.s, base); 3108 else 3109 val.u = div_u64(val.u, base); 3110 --next; 3111 } 3112 } 3113 3114 switch (qualifier) { 3115 case 'H': /* that's 'hh' in format */ 3116 if (is_sign) 3117 *va_arg(args, signed char *) = val.s; 3118 else 3119 *va_arg(args, unsigned char *) = val.u; 3120 break; 3121 case 'h': 3122 if (is_sign) 3123 *va_arg(args, short *) = val.s; 3124 else 3125 *va_arg(args, unsigned short *) = val.u; 3126 break; 3127 case 'l': 3128 if (is_sign) 3129 *va_arg(args, long *) = val.s; 3130 else 3131 *va_arg(args, unsigned long *) = val.u; 3132 break; 3133 case 'L': 3134 if (is_sign) 3135 *va_arg(args, long long *) = val.s; 3136 else 3137 *va_arg(args, unsigned long long *) = val.u; 3138 break; 3139 case 'z': 3140 *va_arg(args, size_t *) = val.u; 3141 break; 3142 default: 3143 if (is_sign) 3144 *va_arg(args, int *) = val.s; 3145 else 3146 *va_arg(args, unsigned int *) = val.u; 3147 break; 3148 } 3149 num++; 3150 3151 if (!next) 3152 break; 3153 str = next; 3154 } 3155 3156 return num; 3157 } 3158 EXPORT_SYMBOL(vsscanf); 3159 3160 /** 3161 * sscanf - Unformat a buffer into a list of arguments 3162 * @buf: input buffer 3163 * @fmt: formatting of buffer 3164 * @...: resulting arguments 3165 */ 3166 int sscanf(const char *buf, const char *fmt, ...) 3167 { 3168 va_list args; 3169 int i; 3170 3171 va_start(args, fmt); 3172 i = vsscanf(buf, fmt, args); 3173 va_end(args); 3174 3175 return i; 3176 } 3177 EXPORT_SYMBOL(sscanf); 3178