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pointer to the end of the parsed string will be placed here 54 * @base: The number base to use 55 * 56 * This function is obsolete.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pointer to the end of the parsed string will be placed here 79 * @base: The number base to use 80 * 81 * This function is obsolete.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 noinline_for_stack 707 char *resource_string(char *buf, char *end, struct resource *res, 708 struct printf_spec spec, const char *fmt) 709 { 710 #ifndef IO_RSRC_PRINTK_SIZE 711 #define IO_RSRC_PRINTK_SIZE 6 712 #endif 713 714 #ifndef MEM_RSRC_PRINTK_SIZE 715 #define MEM_RSRC_PRINTK_SIZE 10 716 #endif 717 static const struct printf_spec io_spec = { 718 .base = 16, 719 .field_width = IO_RSRC_PRINTK_SIZE, 720 .precision = -1, 721 .flags = SPECIAL | SMALL | ZEROPAD, 722 }; 723 static const struct printf_spec mem_spec = { 724 .base = 16, 725 .field_width = MEM_RSRC_PRINTK_SIZE, 726 .precision = -1, 727 .flags = SPECIAL | SMALL | ZEROPAD, 728 }; 729 static const struct printf_spec bus_spec = { 730 .base = 16, 731 .field_width = 2, 732 .precision = -1, 733 .flags = SMALL | ZEROPAD, 734 }; 735 static const struct printf_spec dec_spec = { 736 .base = 10, 737 .precision = -1, 738 .flags = 0, 739 }; 740 static const struct printf_spec str_spec = { 741 .field_width = -1, 742 .precision = 10, 743 .flags = LEFT, 744 }; 745 static const struct printf_spec flag_spec = { 746 .base = 16, 747 .precision = -1, 748 .flags = SPECIAL | SMALL, 749 }; 750 751 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 752 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 753 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 754 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 755 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 756 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 757 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 758 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 759 760 char *p = sym, *pend = sym + sizeof(sym); 761 int decode = (fmt[0] == 'R') ? 1 : 0; 762 const struct printf_spec *specp; 763 764 *p++ = '['; 765 if (res->flags & IORESOURCE_IO) { 766 p = string(p, pend, "io ", str_spec); 767 specp = &io_spec; 768 } else if (res->flags & IORESOURCE_MEM) { 769 p = string(p, pend, "mem ", str_spec); 770 specp = &mem_spec; 771 } else if (res->flags & IORESOURCE_IRQ) { 772 p = string(p, pend, "irq ", str_spec); 773 specp = &dec_spec; 774 } else if (res->flags & IORESOURCE_DMA) { 775 p = string(p, pend, "dma ", str_spec); 776 specp = &dec_spec; 777 } else if (res->flags & IORESOURCE_BUS) { 778 p = string(p, pend, "bus ", str_spec); 779 specp = &bus_spec; 780 } else { 781 p = string(p, pend, "??? ", str_spec); 782 specp = &mem_spec; 783 decode = 0; 784 } 785 if (decode && res->flags & IORESOURCE_UNSET) { 786 p = string(p, pend, "size ", str_spec); 787 p = number(p, pend, resource_size(res), *specp); 788 } else { 789 p = number(p, pend, res->start, *specp); 790 if (res->start != res->end) { 791 *p++ = '-'; 792 p = number(p, pend, res->end, *specp); 793 } 794 } 795 if (decode) { 796 if (res->flags & IORESOURCE_MEM_64) 797 p = string(p, pend, " 64bit", str_spec); 798 if (res->flags & IORESOURCE_PREFETCH) 799 p = string(p, pend, " pref", str_spec); 800 if (res->flags & IORESOURCE_WINDOW) 801 p = string(p, pend, " window", str_spec); 802 if (res->flags & IORESOURCE_DISABLED) 803 p = string(p, pend, " disabled", str_spec); 804 } else { 805 p = string(p, pend, " flags ", str_spec); 806 p = number(p, pend, res->flags, flag_spec); 807 } 808 *p++ = ']'; 809 *p = '\0'; 810 811 return string(buf, end, sym, spec); 812 } 813 814 static noinline_for_stack 815 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 816 const char *fmt) 817 { 818 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 819 negative value, fallback to the default */ 820 char separator; 821 822 if (spec.field_width == 0) 823 /* nothing to print */ 824 return buf; 825 826 if (ZERO_OR_NULL_PTR(addr)) 827 /* NULL pointer */ 828 return string(buf, end, NULL, spec); 829 830 switch (fmt[1]) { 831 case 'C': 832 separator = ':'; 833 break; 834 case 'D': 835 separator = '-'; 836 break; 837 case 'N': 838 separator = 0; 839 break; 840 default: 841 separator = ' '; 842 break; 843 } 844 845 if (spec.field_width > 0) 846 len = min_t(int, spec.field_width, 64); 847 848 for (i = 0; i < len; ++i) { 849 if (buf < end) 850 *buf = hex_asc_hi(addr[i]); 851 ++buf; 852 if (buf < end) 853 *buf = hex_asc_lo(addr[i]); 854 ++buf; 855 856 if (separator && i != len - 1) { 857 if (buf < end) 858 *buf = separator; 859 ++buf; 860 } 861 } 862 863 return buf; 864 } 865 866 static noinline_for_stack 867 char *bitmap_string(char *buf, char *end, unsigned long *bitmap, 868 struct printf_spec spec, const char *fmt) 869 { 870 const int CHUNKSZ = 32; 871 int nr_bits = max_t(int, spec.field_width, 0); 872 int i, chunksz; 873 bool first = true; 874 875 /* reused to print numbers */ 876 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 877 878 chunksz = nr_bits & (CHUNKSZ - 1); 879 if (chunksz == 0) 880 chunksz = CHUNKSZ; 881 882 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 883 for (; i >= 0; i -= CHUNKSZ) { 884 u32 chunkmask, val; 885 int word, bit; 886 887 chunkmask = ((1ULL << chunksz) - 1); 888 word = i / BITS_PER_LONG; 889 bit = i % BITS_PER_LONG; 890 val = (bitmap[word] >> bit) & chunkmask; 891 892 if (!first) { 893 if (buf < end) 894 *buf = ','; 895 buf++; 896 } 897 first = false; 898 899 spec.field_width = DIV_ROUND_UP(chunksz, 4); 900 buf = number(buf, end, val, spec); 901 902 chunksz = CHUNKSZ; 903 } 904 return buf; 905 } 906 907 static noinline_for_stack 908 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap, 909 struct printf_spec spec, const char *fmt) 910 { 911 int nr_bits = max_t(int, spec.field_width, 0); 912 /* current bit is 'cur', most recently seen range is [rbot, rtop] */ 913 int cur, rbot, rtop; 914 bool first = true; 915 916 /* reused to print numbers */ 917 spec = (struct printf_spec){ .base = 10 }; 918 919 rbot = cur = find_first_bit(bitmap, nr_bits); 920 while (cur < nr_bits) { 921 rtop = cur; 922 cur = find_next_bit(bitmap, nr_bits, cur + 1); 923 if (cur < nr_bits && cur <= rtop + 1) 924 continue; 925 926 if (!first) { 927 if (buf < end) 928 *buf = ','; 929 buf++; 930 } 931 first = false; 932 933 buf = number(buf, end, rbot, spec); 934 if (rbot < rtop) { 935 if (buf < end) 936 *buf = '-'; 937 buf++; 938 939 buf = number(buf, end, rtop, spec); 940 } 941 942 rbot = cur; 943 } 944 return buf; 945 } 946 947 static noinline_for_stack 948 char *mac_address_string(char *buf, char *end, u8 *addr, 949 struct printf_spec spec, const char *fmt) 950 { 951 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 952 char *p = mac_addr; 953 int i; 954 char separator; 955 bool reversed = false; 956 957 switch (fmt[1]) { 958 case 'F': 959 separator = '-'; 960 break; 961 962 case 'R': 963 reversed = true; 964 /* fall through */ 965 966 default: 967 separator = ':'; 968 break; 969 } 970 971 for (i = 0; i < 6; i++) { 972 if (reversed) 973 p = hex_byte_pack(p, addr[5 - i]); 974 else 975 p = hex_byte_pack(p, addr[i]); 976 977 if (fmt[0] == 'M' && i != 5) 978 *p++ = separator; 979 } 980 *p = '\0'; 981 982 return string(buf, end, mac_addr, spec); 983 } 984 985 static noinline_for_stack 986 char *ip4_string(char *p, const u8 *addr, const char *fmt) 987 { 988 int i; 989 bool leading_zeros = (fmt[0] == 'i'); 990 int index; 991 int step; 992 993 switch (fmt[2]) { 994 case 'h': 995 #ifdef __BIG_ENDIAN 996 index = 0; 997 step = 1; 998 #else 999 index = 3; 1000 step = -1; 1001 #endif 1002 break; 1003 case 'l': 1004 index = 3; 1005 step = -1; 1006 break; 1007 case 'n': 1008 case 'b': 1009 default: 1010 index = 0; 1011 step = 1; 1012 break; 1013 } 1014 for (i = 0; i < 4; i++) { 1015 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1016 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1017 if (leading_zeros) { 1018 if (digits < 3) 1019 *p++ = '0'; 1020 if (digits < 2) 1021 *p++ = '0'; 1022 } 1023 /* reverse the digits in the quad */ 1024 while (digits--) 1025 *p++ = temp[digits]; 1026 if (i < 3) 1027 *p++ = '.'; 1028 index += step; 1029 } 1030 *p = '\0'; 1031 1032 return p; 1033 } 1034 1035 static noinline_for_stack 1036 char *ip6_compressed_string(char *p, const char *addr) 1037 { 1038 int i, j, range; 1039 unsigned char zerolength[8]; 1040 int longest = 1; 1041 int colonpos = -1; 1042 u16 word; 1043 u8 hi, lo; 1044 bool needcolon = false; 1045 bool useIPv4; 1046 struct in6_addr in6; 1047 1048 memcpy(&in6, addr, sizeof(struct in6_addr)); 1049 1050 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1051 1052 memset(zerolength, 0, sizeof(zerolength)); 1053 1054 if (useIPv4) 1055 range = 6; 1056 else 1057 range = 8; 1058 1059 /* find position of longest 0 run */ 1060 for (i = 0; i < range; i++) { 1061 for (j = i; j < range; j++) { 1062 if (in6.s6_addr16[j] != 0) 1063 break; 1064 zerolength[i]++; 1065 } 1066 } 1067 for (i = 0; i < range; i++) { 1068 if (zerolength[i] > longest) { 1069 longest = zerolength[i]; 1070 colonpos = i; 1071 } 1072 } 1073 if (longest == 1) /* don't compress a single 0 */ 1074 colonpos = -1; 1075 1076 /* emit address */ 1077 for (i = 0; i < range; i++) { 1078 if (i == colonpos) { 1079 if (needcolon || i == 0) 1080 *p++ = ':'; 1081 *p++ = ':'; 1082 needcolon = false; 1083 i += longest - 1; 1084 continue; 1085 } 1086 if (needcolon) { 1087 *p++ = ':'; 1088 needcolon = false; 1089 } 1090 /* hex u16 without leading 0s */ 1091 word = ntohs(in6.s6_addr16[i]); 1092 hi = word >> 8; 1093 lo = word & 0xff; 1094 if (hi) { 1095 if (hi > 0x0f) 1096 p = hex_byte_pack(p, hi); 1097 else 1098 *p++ = hex_asc_lo(hi); 1099 p = hex_byte_pack(p, lo); 1100 } 1101 else if (lo > 0x0f) 1102 p = hex_byte_pack(p, lo); 1103 else 1104 *p++ = hex_asc_lo(lo); 1105 needcolon = true; 1106 } 1107 1108 if (useIPv4) { 1109 if (needcolon) 1110 *p++ = ':'; 1111 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1112 } 1113 *p = '\0'; 1114 1115 return p; 1116 } 1117 1118 static noinline_for_stack 1119 char *ip6_string(char *p, const char *addr, const char *fmt) 1120 { 1121 int i; 1122 1123 for (i = 0; i < 8; i++) { 1124 p = hex_byte_pack(p, *addr++); 1125 p = hex_byte_pack(p, *addr++); 1126 if (fmt[0] == 'I' && i != 7) 1127 *p++ = ':'; 1128 } 1129 *p = '\0'; 1130 1131 return p; 1132 } 1133 1134 static noinline_for_stack 1135 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1136 struct printf_spec spec, const char *fmt) 1137 { 1138 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1139 1140 if (fmt[0] == 'I' && fmt[2] == 'c') 1141 ip6_compressed_string(ip6_addr, addr); 1142 else 1143 ip6_string(ip6_addr, addr, fmt); 1144 1145 return string(buf, end, ip6_addr, spec); 1146 } 1147 1148 static noinline_for_stack 1149 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1150 struct printf_spec spec, const char *fmt) 1151 { 1152 char ip4_addr[sizeof("255.255.255.255")]; 1153 1154 ip4_string(ip4_addr, addr, fmt); 1155 1156 return string(buf, end, ip4_addr, spec); 1157 } 1158 1159 static noinline_for_stack 1160 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1161 struct printf_spec spec, const char *fmt) 1162 { 1163 bool have_p = false, have_s = false, have_f = false, have_c = false; 1164 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1165 sizeof(":12345") + sizeof("/123456789") + 1166 sizeof("%1234567890")]; 1167 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1168 const u8 *addr = (const u8 *) &sa->sin6_addr; 1169 char fmt6[2] = { fmt[0], '6' }; 1170 u8 off = 0; 1171 1172 fmt++; 1173 while (isalpha(*++fmt)) { 1174 switch (*fmt) { 1175 case 'p': 1176 have_p = true; 1177 break; 1178 case 'f': 1179 have_f = true; 1180 break; 1181 case 's': 1182 have_s = true; 1183 break; 1184 case 'c': 1185 have_c = true; 1186 break; 1187 } 1188 } 1189 1190 if (have_p || have_s || have_f) { 1191 *p = '['; 1192 off = 1; 1193 } 1194 1195 if (fmt6[0] == 'I' && have_c) 1196 p = ip6_compressed_string(ip6_addr + off, addr); 1197 else 1198 p = ip6_string(ip6_addr + off, addr, fmt6); 1199 1200 if (have_p || have_s || have_f) 1201 *p++ = ']'; 1202 1203 if (have_p) { 1204 *p++ = ':'; 1205 p = number(p, pend, ntohs(sa->sin6_port), spec); 1206 } 1207 if (have_f) { 1208 *p++ = '/'; 1209 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1210 IPV6_FLOWINFO_MASK), spec); 1211 } 1212 if (have_s) { 1213 *p++ = '%'; 1214 p = number(p, pend, sa->sin6_scope_id, spec); 1215 } 1216 *p = '\0'; 1217 1218 return string(buf, end, ip6_addr, spec); 1219 } 1220 1221 static noinline_for_stack 1222 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1223 struct printf_spec spec, const char *fmt) 1224 { 1225 bool have_p = false; 1226 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1227 char *pend = ip4_addr + sizeof(ip4_addr); 1228 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1229 char fmt4[3] = { fmt[0], '4', 0 }; 1230 1231 fmt++; 1232 while (isalpha(*++fmt)) { 1233 switch (*fmt) { 1234 case 'p': 1235 have_p = true; 1236 break; 1237 case 'h': 1238 case 'l': 1239 case 'n': 1240 case 'b': 1241 fmt4[2] = *fmt; 1242 break; 1243 } 1244 } 1245 1246 p = ip4_string(ip4_addr, addr, fmt4); 1247 if (have_p) { 1248 *p++ = ':'; 1249 p = number(p, pend, ntohs(sa->sin_port), spec); 1250 } 1251 *p = '\0'; 1252 1253 return string(buf, end, ip4_addr, spec); 1254 } 1255 1256 static noinline_for_stack 1257 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1258 const char *fmt) 1259 { 1260 bool found = true; 1261 int count = 1; 1262 unsigned int flags = 0; 1263 int len; 1264 1265 if (spec.field_width == 0) 1266 return buf; /* nothing to print */ 1267 1268 if (ZERO_OR_NULL_PTR(addr)) 1269 return string(buf, end, NULL, spec); /* NULL pointer */ 1270 1271 1272 do { 1273 switch (fmt[count++]) { 1274 case 'a': 1275 flags |= ESCAPE_ANY; 1276 break; 1277 case 'c': 1278 flags |= ESCAPE_SPECIAL; 1279 break; 1280 case 'h': 1281 flags |= ESCAPE_HEX; 1282 break; 1283 case 'n': 1284 flags |= ESCAPE_NULL; 1285 break; 1286 case 'o': 1287 flags |= ESCAPE_OCTAL; 1288 break; 1289 case 'p': 1290 flags |= ESCAPE_NP; 1291 break; 1292 case 's': 1293 flags |= ESCAPE_SPACE; 1294 break; 1295 default: 1296 found = false; 1297 break; 1298 } 1299 } while (found); 1300 1301 if (!flags) 1302 flags = ESCAPE_ANY_NP; 1303 1304 len = spec.field_width < 0 ? 1 : spec.field_width; 1305 1306 /* 1307 * string_escape_mem() writes as many characters as it can to 1308 * the given buffer, and returns the total size of the output 1309 * had the buffer been big enough. 1310 */ 1311 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1312 1313 return buf; 1314 } 1315 1316 static noinline_for_stack 1317 char *uuid_string(char *buf, char *end, const u8 *addr, 1318 struct printf_spec spec, const char *fmt) 1319 { 1320 char uuid[UUID_STRING_LEN + 1]; 1321 char *p = uuid; 1322 int i; 1323 const u8 *index = uuid_index; 1324 bool uc = false; 1325 1326 switch (*(++fmt)) { 1327 case 'L': 1328 uc = true; /* fall-through */ 1329 case 'l': 1330 index = guid_index; 1331 break; 1332 case 'B': 1333 uc = true; 1334 break; 1335 } 1336 1337 for (i = 0; i < 16; i++) { 1338 if (uc) 1339 p = hex_byte_pack_upper(p, addr[index[i]]); 1340 else 1341 p = hex_byte_pack(p, addr[index[i]]); 1342 switch (i) { 1343 case 3: 1344 case 5: 1345 case 7: 1346 case 9: 1347 *p++ = '-'; 1348 break; 1349 } 1350 } 1351 1352 *p = 0; 1353 1354 return string(buf, end, uuid, spec); 1355 } 1356 1357 int kptr_restrict __read_mostly; 1358 1359 static noinline_for_stack 1360 char *restricted_pointer(char *buf, char *end, const void *ptr, 1361 struct printf_spec spec) 1362 { 1363 spec.base = 16; 1364 spec.flags |= SMALL; 1365 if (spec.field_width == -1) { 1366 spec.field_width = 2 * sizeof(ptr); 1367 spec.flags |= ZEROPAD; 1368 } 1369 1370 switch (kptr_restrict) { 1371 case 0: 1372 /* Always print %pK values */ 1373 break; 1374 case 1: { 1375 const struct cred *cred; 1376 1377 /* 1378 * kptr_restrict==1 cannot be used in IRQ context 1379 * because its test for CAP_SYSLOG would be meaningless. 1380 */ 1381 if (in_irq() || in_serving_softirq() || in_nmi()) 1382 return string(buf, end, "pK-error", spec); 1383 1384 /* 1385 * Only print the real pointer value if the current 1386 * process has CAP_SYSLOG and is running with the 1387 * same credentials it started with. This is because 1388 * access to files is checked at open() time, but %pK 1389 * checks permission at read() time. We don't want to 1390 * leak pointer values if a binary opens a file using 1391 * %pK and then elevates privileges before reading it. 1392 */ 1393 cred = current_cred(); 1394 if (!has_capability_noaudit(current, CAP_SYSLOG) || 1395 !uid_eq(cred->euid, cred->uid) || 1396 !gid_eq(cred->egid, cred->gid)) 1397 ptr = NULL; 1398 break; 1399 } 1400 case 2: 1401 default: 1402 /* Always print 0's for %pK */ 1403 ptr = NULL; 1404 break; 1405 } 1406 1407 return number(buf, end, (unsigned long)ptr, spec); 1408 } 1409 1410 static noinline_for_stack 1411 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt) 1412 { 1413 unsigned long long num; 1414 int size; 1415 1416 switch (fmt[1]) { 1417 case 'F': 1418 num = *(const netdev_features_t *)addr; 1419 size = sizeof(netdev_features_t); 1420 break; 1421 default: 1422 num = (unsigned long)addr; 1423 size = sizeof(unsigned long); 1424 break; 1425 } 1426 1427 return special_hex_number(buf, end, num, size); 1428 } 1429 1430 static noinline_for_stack 1431 char *address_val(char *buf, char *end, const void *addr, const char *fmt) 1432 { 1433 unsigned long long num; 1434 int size; 1435 1436 switch (fmt[1]) { 1437 case 'd': 1438 num = *(const dma_addr_t *)addr; 1439 size = sizeof(dma_addr_t); 1440 break; 1441 case 'p': 1442 default: 1443 num = *(const phys_addr_t *)addr; 1444 size = sizeof(phys_addr_t); 1445 break; 1446 } 1447 1448 return special_hex_number(buf, end, num, size); 1449 } 1450 1451 static noinline_for_stack 1452 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1453 const char *fmt) 1454 { 1455 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk) 1456 return string(buf, end, NULL, spec); 1457 1458 switch (fmt[1]) { 1459 case 'r': 1460 return number(buf, end, clk_get_rate(clk), spec); 1461 1462 case 'n': 1463 default: 1464 #ifdef CONFIG_COMMON_CLK 1465 return string(buf, end, __clk_get_name(clk), spec); 1466 #else 1467 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long)); 1468 #endif 1469 } 1470 } 1471 1472 static 1473 char *format_flags(char *buf, char *end, unsigned long flags, 1474 const struct trace_print_flags *names) 1475 { 1476 unsigned long mask; 1477 const struct printf_spec strspec = { 1478 .field_width = -1, 1479 .precision = -1, 1480 }; 1481 const struct printf_spec numspec = { 1482 .flags = SPECIAL|SMALL, 1483 .field_width = -1, 1484 .precision = -1, 1485 .base = 16, 1486 }; 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, strspec); 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, numspec); 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 static const struct printf_spec strspec = { 1552 .field_width = -1, 1553 .precision = -1, 1554 }; 1555 1556 /* special case for root node */ 1557 if (!parent) 1558 return string(buf, end, "/", strspec); 1559 1560 for (depth = 0; parent->parent; depth++) 1561 parent = parent->parent; 1562 1563 for ( ; depth >= 0; depth--) { 1564 buf = string(buf, end, "/", strspec); 1565 buf = string(buf, end, device_node_name_for_depth(np, depth), 1566 strspec); 1567 } 1568 return buf; 1569 } 1570 1571 static noinline_for_stack 1572 char *device_node_string(char *buf, char *end, struct device_node *dn, 1573 struct printf_spec spec, const char *fmt) 1574 { 1575 char tbuf[sizeof("xxxx") + 1]; 1576 const char *p; 1577 int ret; 1578 char *buf_start = buf; 1579 struct property *prop; 1580 bool has_mult, pass; 1581 static const struct printf_spec num_spec = { 1582 .flags = SMALL, 1583 .field_width = -1, 1584 .precision = -1, 1585 .base = 10, 1586 }; 1587 1588 struct printf_spec str_spec = spec; 1589 str_spec.field_width = -1; 1590 1591 if (!IS_ENABLED(CONFIG_OF)) 1592 return string(buf, end, "(!OF)", spec); 1593 1594 if ((unsigned long)dn < PAGE_SIZE) 1595 return string(buf, end, "(null)", spec); 1596 1597 /* simple case without anything any more format specifiers */ 1598 fmt++; 1599 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 1600 fmt = "f"; 1601 1602 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 1603 if (pass) { 1604 if (buf < end) 1605 *buf = ':'; 1606 buf++; 1607 } 1608 1609 switch (*fmt) { 1610 case 'f': /* full_name */ 1611 buf = device_node_gen_full_name(dn, buf, end); 1612 break; 1613 case 'n': /* name */ 1614 buf = string(buf, end, dn->name, str_spec); 1615 break; 1616 case 'p': /* phandle */ 1617 buf = number(buf, end, (unsigned int)dn->phandle, num_spec); 1618 break; 1619 case 'P': /* path-spec */ 1620 p = kbasename(of_node_full_name(dn)); 1621 if (!p[1]) 1622 p = "/"; 1623 buf = string(buf, end, p, str_spec); 1624 break; 1625 case 'F': /* flags */ 1626 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 1627 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 1628 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 1629 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 1630 tbuf[4] = 0; 1631 buf = string(buf, end, tbuf, str_spec); 1632 break; 1633 case 'c': /* major compatible string */ 1634 ret = of_property_read_string(dn, "compatible", &p); 1635 if (!ret) 1636 buf = string(buf, end, p, str_spec); 1637 break; 1638 case 'C': /* full compatible string */ 1639 has_mult = false; 1640 of_property_for_each_string(dn, "compatible", prop, p) { 1641 if (has_mult) 1642 buf = string(buf, end, ",", str_spec); 1643 buf = string(buf, end, "\"", str_spec); 1644 buf = string(buf, end, p, str_spec); 1645 buf = string(buf, end, "\"", str_spec); 1646 1647 has_mult = true; 1648 } 1649 break; 1650 default: 1651 break; 1652 } 1653 } 1654 1655 return widen_string(buf, buf - buf_start, end, spec); 1656 } 1657 1658 static noinline_for_stack 1659 char *pointer_string(char *buf, char *end, const void *ptr, 1660 struct printf_spec spec) 1661 { 1662 spec.base = 16; 1663 spec.flags |= SMALL; 1664 if (spec.field_width == -1) { 1665 spec.field_width = 2 * sizeof(ptr); 1666 spec.flags |= ZEROPAD; 1667 } 1668 1669 return number(buf, end, (unsigned long int)ptr, spec); 1670 } 1671 1672 static bool have_filled_random_ptr_key __read_mostly; 1673 static siphash_key_t ptr_key __read_mostly; 1674 1675 static void fill_random_ptr_key(struct random_ready_callback *unused) 1676 { 1677 get_random_bytes(&ptr_key, sizeof(ptr_key)); 1678 /* 1679 * have_filled_random_ptr_key==true is dependent on get_random_bytes(). 1680 * ptr_to_id() needs to see have_filled_random_ptr_key==true 1681 * after get_random_bytes() returns. 1682 */ 1683 smp_mb(); 1684 WRITE_ONCE(have_filled_random_ptr_key, true); 1685 } 1686 1687 static struct random_ready_callback random_ready = { 1688 .func = fill_random_ptr_key 1689 }; 1690 1691 static int __init initialize_ptr_random(void) 1692 { 1693 int ret = add_random_ready_callback(&random_ready); 1694 1695 if (!ret) { 1696 return 0; 1697 } else if (ret == -EALREADY) { 1698 fill_random_ptr_key(&random_ready); 1699 return 0; 1700 } 1701 1702 return ret; 1703 } 1704 early_initcall(initialize_ptr_random); 1705 1706 /* Maps a pointer to a 32 bit unique identifier. */ 1707 static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec) 1708 { 1709 unsigned long hashval; 1710 const int default_width = 2 * sizeof(ptr); 1711 1712 if (unlikely(!have_filled_random_ptr_key)) { 1713 spec.field_width = default_width; 1714 /* string length must be less than default_width */ 1715 return string(buf, end, "(ptrval)", spec); 1716 } 1717 1718 #ifdef CONFIG_64BIT 1719 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 1720 /* 1721 * Mask off the first 32 bits, this makes explicit that we have 1722 * modified the address (and 32 bits is plenty for a unique ID). 1723 */ 1724 hashval = hashval & 0xffffffff; 1725 #else 1726 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 1727 #endif 1728 1729 spec.flags |= SMALL; 1730 if (spec.field_width == -1) { 1731 spec.field_width = default_width; 1732 spec.flags |= ZEROPAD; 1733 } 1734 spec.base = 16; 1735 1736 return number(buf, end, hashval, spec); 1737 } 1738 1739 /* 1740 * Show a '%p' thing. A kernel extension is that the '%p' is followed 1741 * by an extra set of alphanumeric characters that are extended format 1742 * specifiers. 1743 * 1744 * Please update scripts/checkpatch.pl when adding/removing conversion 1745 * characters. (Search for "check for vsprintf extension"). 1746 * 1747 * Right now we handle: 1748 * 1749 * - 'F' For symbolic function descriptor pointers with offset 1750 * - 'f' For simple symbolic function names without offset 1751 * - 'S' For symbolic direct pointers with offset 1752 * - 's' For symbolic direct pointers without offset 1753 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation 1754 * - 'B' For backtraced symbolic direct pointers with offset 1755 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 1756 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 1757 * - 'b[l]' For a bitmap, the number of bits is determined by the field 1758 * width which must be explicitly specified either as part of the 1759 * format string '%32b[l]' or through '%*b[l]', [l] selects 1760 * range-list format instead of hex format 1761 * - 'M' For a 6-byte MAC address, it prints the address in the 1762 * usual colon-separated hex notation 1763 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 1764 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 1765 * with a dash-separated hex notation 1766 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 1767 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 1768 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 1769 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 1770 * [S][pfs] 1771 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 1772 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 1773 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 1774 * IPv6 omits the colons (01020304...0f) 1775 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 1776 * [S][pfs] 1777 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 1778 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 1779 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 1780 * - 'I[6S]c' for IPv6 addresses printed as specified by 1781 * http://tools.ietf.org/html/rfc5952 1782 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 1783 * of the following flags (see string_escape_mem() for the 1784 * details): 1785 * a - ESCAPE_ANY 1786 * c - ESCAPE_SPECIAL 1787 * h - ESCAPE_HEX 1788 * n - ESCAPE_NULL 1789 * o - ESCAPE_OCTAL 1790 * p - ESCAPE_NP 1791 * s - ESCAPE_SPACE 1792 * By default ESCAPE_ANY_NP is used. 1793 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 1794 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 1795 * Options for %pU are: 1796 * b big endian lower case hex (default) 1797 * B big endian UPPER case hex 1798 * l little endian lower case hex 1799 * L little endian UPPER case hex 1800 * big endian output byte order is: 1801 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 1802 * little endian output byte order is: 1803 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 1804 * - 'V' For a struct va_format which contains a format string * and va_list *, 1805 * call vsnprintf(->format, *->va_list). 1806 * Implements a "recursive vsnprintf". 1807 * Do not use this feature without some mechanism to verify the 1808 * correctness of the format string and va_list arguments. 1809 * - 'K' For a kernel pointer that should be hidden from unprivileged users 1810 * - 'NF' For a netdev_features_t 1811 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 1812 * a certain separator (' ' by default): 1813 * C colon 1814 * D dash 1815 * N no separator 1816 * The maximum supported length is 64 bytes of the input. Consider 1817 * to use print_hex_dump() for the larger input. 1818 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 1819 * (default assumed to be phys_addr_t, passed by reference) 1820 * - 'd[234]' For a dentry name (optionally 2-4 last components) 1821 * - 'D[234]' Same as 'd' but for a struct file 1822 * - 'g' For block_device name (gendisk + partition number) 1823 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 1824 * (legacy clock framework) of the clock 1825 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 1826 * (legacy clock framework) of the clock 1827 * - 'Cr' For a clock, it prints the current rate of the clock 1828 * - 'G' For flags to be printed as a collection of symbolic strings that would 1829 * construct the specific value. Supported flags given by option: 1830 * p page flags (see struct page) given as pointer to unsigned long 1831 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 1832 * v vma flags (VM_*) given as pointer to unsigned long 1833 * - 'O' For a kobject based struct. Must be one of the following: 1834 * - 'OF[fnpPcCF]' For a device tree object 1835 * Without any optional arguments prints the full_name 1836 * f device node full_name 1837 * n device node name 1838 * p device node phandle 1839 * P device node path spec (name + @unit) 1840 * F device node flags 1841 * c major compatible string 1842 * C full compatible string 1843 * 1844 * - 'x' For printing the address. Equivalent to "%lx". 1845 * 1846 * ** When making changes please also update: 1847 * Documentation/core-api/printk-formats.rst 1848 * 1849 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 1850 * function pointers are really function descriptors, which contain a 1851 * pointer to the real address. 1852 * 1853 * Note: The default behaviour (unadorned %p) is to hash the address, 1854 * rendering it useful as a unique identifier. 1855 */ 1856 static noinline_for_stack 1857 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 1858 struct printf_spec spec) 1859 { 1860 const int default_width = 2 * sizeof(void *); 1861 1862 if (!ptr && *fmt != 'K' && *fmt != 'x') { 1863 /* 1864 * Print (null) with the same width as a pointer so it makes 1865 * tabular output look nice. 1866 */ 1867 if (spec.field_width == -1) 1868 spec.field_width = default_width; 1869 return string(buf, end, "(null)", spec); 1870 } 1871 1872 switch (*fmt) { 1873 case 'F': 1874 case 'f': 1875 case 'S': 1876 case 's': 1877 ptr = dereference_symbol_descriptor(ptr); 1878 /* Fallthrough */ 1879 case 'B': 1880 return symbol_string(buf, end, ptr, spec, fmt); 1881 case 'R': 1882 case 'r': 1883 return resource_string(buf, end, ptr, spec, fmt); 1884 case 'h': 1885 return hex_string(buf, end, ptr, spec, fmt); 1886 case 'b': 1887 switch (fmt[1]) { 1888 case 'l': 1889 return bitmap_list_string(buf, end, ptr, spec, fmt); 1890 default: 1891 return bitmap_string(buf, end, ptr, spec, fmt); 1892 } 1893 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 1894 case 'm': /* Contiguous: 000102030405 */ 1895 /* [mM]F (FDDI) */ 1896 /* [mM]R (Reverse order; Bluetooth) */ 1897 return mac_address_string(buf, end, ptr, spec, fmt); 1898 case 'I': /* Formatted IP supported 1899 * 4: 1.2.3.4 1900 * 6: 0001:0203:...:0708 1901 * 6c: 1::708 or 1::1.2.3.4 1902 */ 1903 case 'i': /* Contiguous: 1904 * 4: 001.002.003.004 1905 * 6: 000102...0f 1906 */ 1907 switch (fmt[1]) { 1908 case '6': 1909 return ip6_addr_string(buf, end, ptr, spec, fmt); 1910 case '4': 1911 return ip4_addr_string(buf, end, ptr, spec, fmt); 1912 case 'S': { 1913 const union { 1914 struct sockaddr raw; 1915 struct sockaddr_in v4; 1916 struct sockaddr_in6 v6; 1917 } *sa = ptr; 1918 1919 switch (sa->raw.sa_family) { 1920 case AF_INET: 1921 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1922 case AF_INET6: 1923 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1924 default: 1925 return string(buf, end, "(invalid address)", spec); 1926 }} 1927 } 1928 break; 1929 case 'E': 1930 return escaped_string(buf, end, ptr, spec, fmt); 1931 case 'U': 1932 return uuid_string(buf, end, ptr, spec, fmt); 1933 case 'V': 1934 { 1935 va_list va; 1936 1937 va_copy(va, *((struct va_format *)ptr)->va); 1938 buf += vsnprintf(buf, end > buf ? end - buf : 0, 1939 ((struct va_format *)ptr)->fmt, va); 1940 va_end(va); 1941 return buf; 1942 } 1943 case 'K': 1944 if (!kptr_restrict) 1945 break; 1946 return restricted_pointer(buf, end, ptr, spec); 1947 case 'N': 1948 return netdev_bits(buf, end, ptr, fmt); 1949 case 'a': 1950 return address_val(buf, end, ptr, fmt); 1951 case 'd': 1952 return dentry_name(buf, end, ptr, spec, fmt); 1953 case 'C': 1954 return clock(buf, end, ptr, spec, fmt); 1955 case 'D': 1956 return dentry_name(buf, end, 1957 ((const struct file *)ptr)->f_path.dentry, 1958 spec, fmt); 1959 #ifdef CONFIG_BLOCK 1960 case 'g': 1961 return bdev_name(buf, end, ptr, spec, fmt); 1962 #endif 1963 1964 case 'G': 1965 return flags_string(buf, end, ptr, fmt); 1966 case 'O': 1967 switch (fmt[1]) { 1968 case 'F': 1969 return device_node_string(buf, end, ptr, spec, fmt + 1); 1970 } 1971 case 'x': 1972 return pointer_string(buf, end, ptr, spec); 1973 } 1974 1975 /* default is to _not_ leak addresses, hash before printing */ 1976 return ptr_to_id(buf, end, ptr, spec); 1977 } 1978 1979 /* 1980 * Helper function to decode printf style format. 1981 * Each call decode a token from the format and return the 1982 * number of characters read (or likely the delta where it wants 1983 * to go on the next call). 1984 * The decoded token is returned through the parameters 1985 * 1986 * 'h', 'l', or 'L' for integer fields 1987 * 'z' support added 23/7/1999 S.H. 1988 * 'z' changed to 'Z' --davidm 1/25/99 1989 * 'Z' changed to 'z' --adobriyan 2017-01-25 1990 * 't' added for ptrdiff_t 1991 * 1992 * @fmt: the format string 1993 * @type of the token returned 1994 * @flags: various flags such as +, -, # tokens.. 1995 * @field_width: overwritten width 1996 * @base: base of the number (octal, hex, ...) 1997 * @precision: precision of a number 1998 * @qualifier: qualifier of a number (long, size_t, ...) 1999 */ 2000 static noinline_for_stack 2001 int format_decode(const char *fmt, struct printf_spec *spec) 2002 { 2003 const char *start = fmt; 2004 char qualifier; 2005 2006 /* we finished early by reading the field width */ 2007 if (spec->type == FORMAT_TYPE_WIDTH) { 2008 if (spec->field_width < 0) { 2009 spec->field_width = -spec->field_width; 2010 spec->flags |= LEFT; 2011 } 2012 spec->type = FORMAT_TYPE_NONE; 2013 goto precision; 2014 } 2015 2016 /* we finished early by reading the precision */ 2017 if (spec->type == FORMAT_TYPE_PRECISION) { 2018 if (spec->precision < 0) 2019 spec->precision = 0; 2020 2021 spec->type = FORMAT_TYPE_NONE; 2022 goto qualifier; 2023 } 2024 2025 /* By default */ 2026 spec->type = FORMAT_TYPE_NONE; 2027 2028 for (; *fmt ; ++fmt) { 2029 if (*fmt == '%') 2030 break; 2031 } 2032 2033 /* Return the current non-format string */ 2034 if (fmt != start || !*fmt) 2035 return fmt - start; 2036 2037 /* Process flags */ 2038 spec->flags = 0; 2039 2040 while (1) { /* this also skips first '%' */ 2041 bool found = true; 2042 2043 ++fmt; 2044 2045 switch (*fmt) { 2046 case '-': spec->flags |= LEFT; break; 2047 case '+': spec->flags |= PLUS; break; 2048 case ' ': spec->flags |= SPACE; break; 2049 case '#': spec->flags |= SPECIAL; break; 2050 case '0': spec->flags |= ZEROPAD; break; 2051 default: found = false; 2052 } 2053 2054 if (!found) 2055 break; 2056 } 2057 2058 /* get field width */ 2059 spec->field_width = -1; 2060 2061 if (isdigit(*fmt)) 2062 spec->field_width = skip_atoi(&fmt); 2063 else if (*fmt == '*') { 2064 /* it's the next argument */ 2065 spec->type = FORMAT_TYPE_WIDTH; 2066 return ++fmt - start; 2067 } 2068 2069 precision: 2070 /* get the precision */ 2071 spec->precision = -1; 2072 if (*fmt == '.') { 2073 ++fmt; 2074 if (isdigit(*fmt)) { 2075 spec->precision = skip_atoi(&fmt); 2076 if (spec->precision < 0) 2077 spec->precision = 0; 2078 } else if (*fmt == '*') { 2079 /* it's the next argument */ 2080 spec->type = FORMAT_TYPE_PRECISION; 2081 return ++fmt - start; 2082 } 2083 } 2084 2085 qualifier: 2086 /* get the conversion qualifier */ 2087 qualifier = 0; 2088 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2089 *fmt == 'z' || *fmt == 't') { 2090 qualifier = *fmt++; 2091 if (unlikely(qualifier == *fmt)) { 2092 if (qualifier == 'l') { 2093 qualifier = 'L'; 2094 ++fmt; 2095 } else if (qualifier == 'h') { 2096 qualifier = 'H'; 2097 ++fmt; 2098 } 2099 } 2100 } 2101 2102 /* default base */ 2103 spec->base = 10; 2104 switch (*fmt) { 2105 case 'c': 2106 spec->type = FORMAT_TYPE_CHAR; 2107 return ++fmt - start; 2108 2109 case 's': 2110 spec->type = FORMAT_TYPE_STR; 2111 return ++fmt - start; 2112 2113 case 'p': 2114 spec->type = FORMAT_TYPE_PTR; 2115 return ++fmt - start; 2116 2117 case '%': 2118 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2119 return ++fmt - start; 2120 2121 /* integer number formats - set up the flags and "break" */ 2122 case 'o': 2123 spec->base = 8; 2124 break; 2125 2126 case 'x': 2127 spec->flags |= SMALL; 2128 2129 case 'X': 2130 spec->base = 16; 2131 break; 2132 2133 case 'd': 2134 case 'i': 2135 spec->flags |= SIGN; 2136 case 'u': 2137 break; 2138 2139 case 'n': 2140 /* 2141 * Since %n poses a greater security risk than 2142 * utility, treat it as any other invalid or 2143 * unsupported format specifier. 2144 */ 2145 /* Fall-through */ 2146 2147 default: 2148 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2149 spec->type = FORMAT_TYPE_INVALID; 2150 return fmt - start; 2151 } 2152 2153 if (qualifier == 'L') 2154 spec->type = FORMAT_TYPE_LONG_LONG; 2155 else if (qualifier == 'l') { 2156 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2157 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2158 } else if (qualifier == 'z') { 2159 spec->type = FORMAT_TYPE_SIZE_T; 2160 } else if (qualifier == 't') { 2161 spec->type = FORMAT_TYPE_PTRDIFF; 2162 } else if (qualifier == 'H') { 2163 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2164 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2165 } else if (qualifier == 'h') { 2166 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2167 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2168 } else { 2169 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2170 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2171 } 2172 2173 return ++fmt - start; 2174 } 2175 2176 static void 2177 set_field_width(struct printf_spec *spec, int width) 2178 { 2179 spec->field_width = width; 2180 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2181 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2182 } 2183 } 2184 2185 static void 2186 set_precision(struct printf_spec *spec, int prec) 2187 { 2188 spec->precision = prec; 2189 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2190 spec->precision = clamp(prec, 0, PRECISION_MAX); 2191 } 2192 } 2193 2194 /** 2195 * vsnprintf - Format a string and place it in a buffer 2196 * @buf: The buffer to place the result into 2197 * @size: The size of the buffer, including the trailing null space 2198 * @fmt: The format string to use 2199 * @args: Arguments for the format string 2200 * 2201 * This function generally follows C99 vsnprintf, but has some 2202 * extensions and a few limitations: 2203 * 2204 * - ``%n`` is unsupported 2205 * - ``%p*`` is handled by pointer() 2206 * 2207 * See pointer() or Documentation/core-api/printk-formats.rst for more 2208 * extensive description. 2209 * 2210 * **Please update the documentation in both places when making changes** 2211 * 2212 * The return value is the number of characters which would 2213 * be generated for the given input, excluding the trailing 2214 * '\0', as per ISO C99. If you want to have the exact 2215 * number of characters written into @buf as return value 2216 * (not including the trailing '\0'), use vscnprintf(). If the 2217 * return is greater than or equal to @size, the resulting 2218 * string is truncated. 2219 * 2220 * If you're not already dealing with a va_list consider using snprintf(). 2221 */ 2222 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2223 { 2224 unsigned long long num; 2225 char *str, *end; 2226 struct printf_spec spec = {0}; 2227 2228 /* Reject out-of-range values early. Large positive sizes are 2229 used for unknown buffer sizes. */ 2230 if (WARN_ON_ONCE(size > INT_MAX)) 2231 return 0; 2232 2233 str = buf; 2234 end = buf + size; 2235 2236 /* Make sure end is always >= buf */ 2237 if (end < buf) { 2238 end = ((void *)-1); 2239 size = end - buf; 2240 } 2241 2242 while (*fmt) { 2243 const char *old_fmt = fmt; 2244 int read = format_decode(fmt, &spec); 2245 2246 fmt += read; 2247 2248 switch (spec.type) { 2249 case FORMAT_TYPE_NONE: { 2250 int copy = read; 2251 if (str < end) { 2252 if (copy > end - str) 2253 copy = end - str; 2254 memcpy(str, old_fmt, copy); 2255 } 2256 str += read; 2257 break; 2258 } 2259 2260 case FORMAT_TYPE_WIDTH: 2261 set_field_width(&spec, va_arg(args, int)); 2262 break; 2263 2264 case FORMAT_TYPE_PRECISION: 2265 set_precision(&spec, va_arg(args, int)); 2266 break; 2267 2268 case FORMAT_TYPE_CHAR: { 2269 char c; 2270 2271 if (!(spec.flags & LEFT)) { 2272 while (--spec.field_width > 0) { 2273 if (str < end) 2274 *str = ' '; 2275 ++str; 2276 2277 } 2278 } 2279 c = (unsigned char) va_arg(args, int); 2280 if (str < end) 2281 *str = c; 2282 ++str; 2283 while (--spec.field_width > 0) { 2284 if (str < end) 2285 *str = ' '; 2286 ++str; 2287 } 2288 break; 2289 } 2290 2291 case FORMAT_TYPE_STR: 2292 str = string(str, end, va_arg(args, char *), spec); 2293 break; 2294 2295 case FORMAT_TYPE_PTR: 2296 str = pointer(fmt, str, end, va_arg(args, void *), 2297 spec); 2298 while (isalnum(*fmt)) 2299 fmt++; 2300 break; 2301 2302 case FORMAT_TYPE_PERCENT_CHAR: 2303 if (str < end) 2304 *str = '%'; 2305 ++str; 2306 break; 2307 2308 case FORMAT_TYPE_INVALID: 2309 /* 2310 * Presumably the arguments passed gcc's type 2311 * checking, but there is no safe or sane way 2312 * for us to continue parsing the format and 2313 * fetching from the va_list; the remaining 2314 * specifiers and arguments would be out of 2315 * sync. 2316 */ 2317 goto out; 2318 2319 default: 2320 switch (spec.type) { 2321 case FORMAT_TYPE_LONG_LONG: 2322 num = va_arg(args, long long); 2323 break; 2324 case FORMAT_TYPE_ULONG: 2325 num = va_arg(args, unsigned long); 2326 break; 2327 case FORMAT_TYPE_LONG: 2328 num = va_arg(args, long); 2329 break; 2330 case FORMAT_TYPE_SIZE_T: 2331 if (spec.flags & SIGN) 2332 num = va_arg(args, ssize_t); 2333 else 2334 num = va_arg(args, size_t); 2335 break; 2336 case FORMAT_TYPE_PTRDIFF: 2337 num = va_arg(args, ptrdiff_t); 2338 break; 2339 case FORMAT_TYPE_UBYTE: 2340 num = (unsigned char) va_arg(args, int); 2341 break; 2342 case FORMAT_TYPE_BYTE: 2343 num = (signed char) va_arg(args, int); 2344 break; 2345 case FORMAT_TYPE_USHORT: 2346 num = (unsigned short) va_arg(args, int); 2347 break; 2348 case FORMAT_TYPE_SHORT: 2349 num = (short) va_arg(args, int); 2350 break; 2351 case FORMAT_TYPE_INT: 2352 num = (int) va_arg(args, int); 2353 break; 2354 default: 2355 num = va_arg(args, unsigned int); 2356 } 2357 2358 str = number(str, end, num, spec); 2359 } 2360 } 2361 2362 out: 2363 if (size > 0) { 2364 if (str < end) 2365 *str = '\0'; 2366 else 2367 end[-1] = '\0'; 2368 } 2369 2370 /* the trailing null byte doesn't count towards the total */ 2371 return str-buf; 2372 2373 } 2374 EXPORT_SYMBOL(vsnprintf); 2375 2376 /** 2377 * vscnprintf - Format a string and place it in a buffer 2378 * @buf: The buffer to place the result into 2379 * @size: The size of the buffer, including the trailing null space 2380 * @fmt: The format string to use 2381 * @args: Arguments for the format string 2382 * 2383 * The return value is the number of characters which have been written into 2384 * the @buf not including the trailing '\0'. If @size is == 0 the function 2385 * returns 0. 2386 * 2387 * If you're not already dealing with a va_list consider using scnprintf(). 2388 * 2389 * See the vsnprintf() documentation for format string extensions over C99. 2390 */ 2391 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2392 { 2393 int i; 2394 2395 i = vsnprintf(buf, size, fmt, args); 2396 2397 if (likely(i < size)) 2398 return i; 2399 if (size != 0) 2400 return size - 1; 2401 return 0; 2402 } 2403 EXPORT_SYMBOL(vscnprintf); 2404 2405 /** 2406 * snprintf - Format a string and place it in a buffer 2407 * @buf: The buffer to place the result into 2408 * @size: The size of the buffer, including the trailing null space 2409 * @fmt: The format string to use 2410 * @...: Arguments for the format string 2411 * 2412 * The return value is the number of characters which would be 2413 * generated for the given input, excluding the trailing null, 2414 * as per ISO C99. If the return is greater than or equal to 2415 * @size, the resulting string is truncated. 2416 * 2417 * See the vsnprintf() documentation for format string extensions over C99. 2418 */ 2419 int snprintf(char *buf, size_t size, const char *fmt, ...) 2420 { 2421 va_list args; 2422 int i; 2423 2424 va_start(args, fmt); 2425 i = vsnprintf(buf, size, fmt, args); 2426 va_end(args); 2427 2428 return i; 2429 } 2430 EXPORT_SYMBOL(snprintf); 2431 2432 /** 2433 * scnprintf - Format a string and place it in a buffer 2434 * @buf: The buffer to place the result into 2435 * @size: The size of the buffer, including the trailing null space 2436 * @fmt: The format string to use 2437 * @...: Arguments for the format string 2438 * 2439 * The return value is the number of characters written into @buf not including 2440 * the trailing '\0'. If @size is == 0 the function returns 0. 2441 */ 2442 2443 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2444 { 2445 va_list args; 2446 int i; 2447 2448 va_start(args, fmt); 2449 i = vscnprintf(buf, size, fmt, args); 2450 va_end(args); 2451 2452 return i; 2453 } 2454 EXPORT_SYMBOL(scnprintf); 2455 2456 /** 2457 * vsprintf - Format a string and place it in a buffer 2458 * @buf: The buffer to place the result into 2459 * @fmt: The format string to use 2460 * @args: Arguments for the format string 2461 * 2462 * The function returns the number of characters written 2463 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2464 * buffer overflows. 2465 * 2466 * If you're not already dealing with a va_list consider using sprintf(). 2467 * 2468 * See the vsnprintf() documentation for format string extensions over C99. 2469 */ 2470 int vsprintf(char *buf, const char *fmt, va_list args) 2471 { 2472 return vsnprintf(buf, INT_MAX, fmt, args); 2473 } 2474 EXPORT_SYMBOL(vsprintf); 2475 2476 /** 2477 * sprintf - Format a string and place it in a buffer 2478 * @buf: The buffer to place the result into 2479 * @fmt: The format string to use 2480 * @...: Arguments for the format string 2481 * 2482 * The function returns the number of characters written 2483 * into @buf. Use snprintf() or scnprintf() in order to avoid 2484 * buffer overflows. 2485 * 2486 * See the vsnprintf() documentation for format string extensions over C99. 2487 */ 2488 int sprintf(char *buf, const char *fmt, ...) 2489 { 2490 va_list args; 2491 int i; 2492 2493 va_start(args, fmt); 2494 i = vsnprintf(buf, INT_MAX, fmt, args); 2495 va_end(args); 2496 2497 return i; 2498 } 2499 EXPORT_SYMBOL(sprintf); 2500 2501 #ifdef CONFIG_BINARY_PRINTF 2502 /* 2503 * bprintf service: 2504 * vbin_printf() - VA arguments to binary data 2505 * bstr_printf() - Binary data to text string 2506 */ 2507 2508 /** 2509 * vbin_printf - Parse a format string and place args' binary value in a buffer 2510 * @bin_buf: The buffer to place args' binary value 2511 * @size: The size of the buffer(by words(32bits), not characters) 2512 * @fmt: The format string to use 2513 * @args: Arguments for the format string 2514 * 2515 * The format follows C99 vsnprintf, except %n is ignored, and its argument 2516 * is skipped. 2517 * 2518 * The return value is the number of words(32bits) which would be generated for 2519 * the given input. 2520 * 2521 * NOTE: 2522 * If the return value is greater than @size, the resulting bin_buf is NOT 2523 * valid for bstr_printf(). 2524 */ 2525 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 2526 { 2527 struct printf_spec spec = {0}; 2528 char *str, *end; 2529 int width; 2530 2531 str = (char *)bin_buf; 2532 end = (char *)(bin_buf + size); 2533 2534 #define save_arg(type) \ 2535 ({ \ 2536 unsigned long long value; \ 2537 if (sizeof(type) == 8) { \ 2538 unsigned long long val8; \ 2539 str = PTR_ALIGN(str, sizeof(u32)); \ 2540 val8 = va_arg(args, unsigned long long); \ 2541 if (str + sizeof(type) <= end) { \ 2542 *(u32 *)str = *(u32 *)&val8; \ 2543 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 2544 } \ 2545 value = val8; \ 2546 } else { \ 2547 unsigned int val4; \ 2548 str = PTR_ALIGN(str, sizeof(type)); \ 2549 val4 = va_arg(args, int); \ 2550 if (str + sizeof(type) <= end) \ 2551 *(typeof(type) *)str = (type)(long)val4; \ 2552 value = (unsigned long long)val4; \ 2553 } \ 2554 str += sizeof(type); \ 2555 value; \ 2556 }) 2557 2558 while (*fmt) { 2559 int read = format_decode(fmt, &spec); 2560 2561 fmt += read; 2562 2563 switch (spec.type) { 2564 case FORMAT_TYPE_NONE: 2565 case FORMAT_TYPE_PERCENT_CHAR: 2566 break; 2567 case FORMAT_TYPE_INVALID: 2568 goto out; 2569 2570 case FORMAT_TYPE_WIDTH: 2571 case FORMAT_TYPE_PRECISION: 2572 width = (int)save_arg(int); 2573 /* Pointers may require the width */ 2574 if (*fmt == 'p') 2575 set_field_width(&spec, width); 2576 break; 2577 2578 case FORMAT_TYPE_CHAR: 2579 save_arg(char); 2580 break; 2581 2582 case FORMAT_TYPE_STR: { 2583 const char *save_str = va_arg(args, char *); 2584 size_t len; 2585 2586 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 2587 || (unsigned long)save_str < PAGE_SIZE) 2588 save_str = "(null)"; 2589 len = strlen(save_str) + 1; 2590 if (str + len < end) 2591 memcpy(str, save_str, len); 2592 str += len; 2593 break; 2594 } 2595 2596 case FORMAT_TYPE_PTR: 2597 /* Dereferenced pointers must be done now */ 2598 switch (*fmt) { 2599 /* Dereference of functions is still OK */ 2600 case 'S': 2601 case 's': 2602 case 'F': 2603 case 'f': 2604 case 'x': 2605 case 'K': 2606 save_arg(void *); 2607 break; 2608 default: 2609 if (!isalnum(*fmt)) { 2610 save_arg(void *); 2611 break; 2612 } 2613 str = pointer(fmt, str, end, va_arg(args, void *), 2614 spec); 2615 if (str + 1 < end) 2616 *str++ = '\0'; 2617 else 2618 end[-1] = '\0'; /* Must be nul terminated */ 2619 } 2620 /* skip all alphanumeric pointer suffixes */ 2621 while (isalnum(*fmt)) 2622 fmt++; 2623 break; 2624 2625 default: 2626 switch (spec.type) { 2627 2628 case FORMAT_TYPE_LONG_LONG: 2629 save_arg(long long); 2630 break; 2631 case FORMAT_TYPE_ULONG: 2632 case FORMAT_TYPE_LONG: 2633 save_arg(unsigned long); 2634 break; 2635 case FORMAT_TYPE_SIZE_T: 2636 save_arg(size_t); 2637 break; 2638 case FORMAT_TYPE_PTRDIFF: 2639 save_arg(ptrdiff_t); 2640 break; 2641 case FORMAT_TYPE_UBYTE: 2642 case FORMAT_TYPE_BYTE: 2643 save_arg(char); 2644 break; 2645 case FORMAT_TYPE_USHORT: 2646 case FORMAT_TYPE_SHORT: 2647 save_arg(short); 2648 break; 2649 default: 2650 save_arg(int); 2651 } 2652 } 2653 } 2654 2655 out: 2656 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 2657 #undef save_arg 2658 } 2659 EXPORT_SYMBOL_GPL(vbin_printf); 2660 2661 /** 2662 * bstr_printf - Format a string from binary arguments and place it in a buffer 2663 * @buf: The buffer to place the result into 2664 * @size: The size of the buffer, including the trailing null space 2665 * @fmt: The format string to use 2666 * @bin_buf: Binary arguments for the format string 2667 * 2668 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 2669 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 2670 * a binary buffer that generated by vbin_printf. 2671 * 2672 * The format follows C99 vsnprintf, but has some extensions: 2673 * see vsnprintf comment for details. 2674 * 2675 * The return value is the number of characters which would 2676 * be generated for the given input, excluding the trailing 2677 * '\0', as per ISO C99. If you want to have the exact 2678 * number of characters written into @buf as return value 2679 * (not including the trailing '\0'), use vscnprintf(). If the 2680 * return is greater than or equal to @size, the resulting 2681 * string is truncated. 2682 */ 2683 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 2684 { 2685 struct printf_spec spec = {0}; 2686 char *str, *end; 2687 const char *args = (const char *)bin_buf; 2688 2689 if (WARN_ON_ONCE(size > INT_MAX)) 2690 return 0; 2691 2692 str = buf; 2693 end = buf + size; 2694 2695 #define get_arg(type) \ 2696 ({ \ 2697 typeof(type) value; \ 2698 if (sizeof(type) == 8) { \ 2699 args = PTR_ALIGN(args, sizeof(u32)); \ 2700 *(u32 *)&value = *(u32 *)args; \ 2701 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 2702 } else { \ 2703 args = PTR_ALIGN(args, sizeof(type)); \ 2704 value = *(typeof(type) *)args; \ 2705 } \ 2706 args += sizeof(type); \ 2707 value; \ 2708 }) 2709 2710 /* Make sure end is always >= buf */ 2711 if (end < buf) { 2712 end = ((void *)-1); 2713 size = end - buf; 2714 } 2715 2716 while (*fmt) { 2717 const char *old_fmt = fmt; 2718 int read = format_decode(fmt, &spec); 2719 2720 fmt += read; 2721 2722 switch (spec.type) { 2723 case FORMAT_TYPE_NONE: { 2724 int copy = read; 2725 if (str < end) { 2726 if (copy > end - str) 2727 copy = end - str; 2728 memcpy(str, old_fmt, copy); 2729 } 2730 str += read; 2731 break; 2732 } 2733 2734 case FORMAT_TYPE_WIDTH: 2735 set_field_width(&spec, get_arg(int)); 2736 break; 2737 2738 case FORMAT_TYPE_PRECISION: 2739 set_precision(&spec, get_arg(int)); 2740 break; 2741 2742 case FORMAT_TYPE_CHAR: { 2743 char c; 2744 2745 if (!(spec.flags & LEFT)) { 2746 while (--spec.field_width > 0) { 2747 if (str < end) 2748 *str = ' '; 2749 ++str; 2750 } 2751 } 2752 c = (unsigned char) get_arg(char); 2753 if (str < end) 2754 *str = c; 2755 ++str; 2756 while (--spec.field_width > 0) { 2757 if (str < end) 2758 *str = ' '; 2759 ++str; 2760 } 2761 break; 2762 } 2763 2764 case FORMAT_TYPE_STR: { 2765 const char *str_arg = args; 2766 args += strlen(str_arg) + 1; 2767 str = string(str, end, (char *)str_arg, spec); 2768 break; 2769 } 2770 2771 case FORMAT_TYPE_PTR: { 2772 bool process = false; 2773 int copy, len; 2774 /* Non function dereferences were already done */ 2775 switch (*fmt) { 2776 case 'S': 2777 case 's': 2778 case 'F': 2779 case 'f': 2780 case 'x': 2781 case 'K': 2782 process = true; 2783 break; 2784 default: 2785 if (!isalnum(*fmt)) { 2786 process = true; 2787 break; 2788 } 2789 /* Pointer dereference was already processed */ 2790 if (str < end) { 2791 len = copy = strlen(args); 2792 if (copy > end - str) 2793 copy = end - str; 2794 memcpy(str, args, copy); 2795 str += len; 2796 args += len; 2797 } 2798 } 2799 if (process) 2800 str = pointer(fmt, str, end, get_arg(void *), spec); 2801 2802 while (isalnum(*fmt)) 2803 fmt++; 2804 break; 2805 } 2806 2807 case FORMAT_TYPE_PERCENT_CHAR: 2808 if (str < end) 2809 *str = '%'; 2810 ++str; 2811 break; 2812 2813 case FORMAT_TYPE_INVALID: 2814 goto out; 2815 2816 default: { 2817 unsigned long long num; 2818 2819 switch (spec.type) { 2820 2821 case FORMAT_TYPE_LONG_LONG: 2822 num = get_arg(long long); 2823 break; 2824 case FORMAT_TYPE_ULONG: 2825 case FORMAT_TYPE_LONG: 2826 num = get_arg(unsigned long); 2827 break; 2828 case FORMAT_TYPE_SIZE_T: 2829 num = get_arg(size_t); 2830 break; 2831 case FORMAT_TYPE_PTRDIFF: 2832 num = get_arg(ptrdiff_t); 2833 break; 2834 case FORMAT_TYPE_UBYTE: 2835 num = get_arg(unsigned char); 2836 break; 2837 case FORMAT_TYPE_BYTE: 2838 num = get_arg(signed char); 2839 break; 2840 case FORMAT_TYPE_USHORT: 2841 num = get_arg(unsigned short); 2842 break; 2843 case FORMAT_TYPE_SHORT: 2844 num = get_arg(short); 2845 break; 2846 case FORMAT_TYPE_UINT: 2847 num = get_arg(unsigned int); 2848 break; 2849 default: 2850 num = get_arg(int); 2851 } 2852 2853 str = number(str, end, num, spec); 2854 } /* default: */ 2855 } /* switch(spec.type) */ 2856 } /* while(*fmt) */ 2857 2858 out: 2859 if (size > 0) { 2860 if (str < end) 2861 *str = '\0'; 2862 else 2863 end[-1] = '\0'; 2864 } 2865 2866 #undef get_arg 2867 2868 /* the trailing null byte doesn't count towards the total */ 2869 return str - buf; 2870 } 2871 EXPORT_SYMBOL_GPL(bstr_printf); 2872 2873 /** 2874 * bprintf - Parse a format string and place args' binary value in a buffer 2875 * @bin_buf: The buffer to place args' binary value 2876 * @size: The size of the buffer(by words(32bits), not characters) 2877 * @fmt: The format string to use 2878 * @...: Arguments for the format string 2879 * 2880 * The function returns the number of words(u32) written 2881 * into @bin_buf. 2882 */ 2883 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 2884 { 2885 va_list args; 2886 int ret; 2887 2888 va_start(args, fmt); 2889 ret = vbin_printf(bin_buf, size, fmt, args); 2890 va_end(args); 2891 2892 return ret; 2893 } 2894 EXPORT_SYMBOL_GPL(bprintf); 2895 2896 #endif /* CONFIG_BINARY_PRINTF */ 2897 2898 /** 2899 * vsscanf - Unformat a buffer into a list of arguments 2900 * @buf: input buffer 2901 * @fmt: format of buffer 2902 * @args: arguments 2903 */ 2904 int vsscanf(const char *buf, const char *fmt, va_list args) 2905 { 2906 const char *str = buf; 2907 char *next; 2908 char digit; 2909 int num = 0; 2910 u8 qualifier; 2911 unsigned int base; 2912 union { 2913 long long s; 2914 unsigned long long u; 2915 } val; 2916 s16 field_width; 2917 bool is_sign; 2918 2919 while (*fmt) { 2920 /* skip any white space in format */ 2921 /* white space in format matchs any amount of 2922 * white space, including none, in the input. 2923 */ 2924 if (isspace(*fmt)) { 2925 fmt = skip_spaces(++fmt); 2926 str = skip_spaces(str); 2927 } 2928 2929 /* anything that is not a conversion must match exactly */ 2930 if (*fmt != '%' && *fmt) { 2931 if (*fmt++ != *str++) 2932 break; 2933 continue; 2934 } 2935 2936 if (!*fmt) 2937 break; 2938 ++fmt; 2939 2940 /* skip this conversion. 2941 * advance both strings to next white space 2942 */ 2943 if (*fmt == '*') { 2944 if (!*str) 2945 break; 2946 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 2947 /* '%*[' not yet supported, invalid format */ 2948 if (*fmt == '[') 2949 return num; 2950 fmt++; 2951 } 2952 while (!isspace(*str) && *str) 2953 str++; 2954 continue; 2955 } 2956 2957 /* get field width */ 2958 field_width = -1; 2959 if (isdigit(*fmt)) { 2960 field_width = skip_atoi(&fmt); 2961 if (field_width <= 0) 2962 break; 2963 } 2964 2965 /* get conversion qualifier */ 2966 qualifier = -1; 2967 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2968 *fmt == 'z') { 2969 qualifier = *fmt++; 2970 if (unlikely(qualifier == *fmt)) { 2971 if (qualifier == 'h') { 2972 qualifier = 'H'; 2973 fmt++; 2974 } else if (qualifier == 'l') { 2975 qualifier = 'L'; 2976 fmt++; 2977 } 2978 } 2979 } 2980 2981 if (!*fmt) 2982 break; 2983 2984 if (*fmt == 'n') { 2985 /* return number of characters read so far */ 2986 *va_arg(args, int *) = str - buf; 2987 ++fmt; 2988 continue; 2989 } 2990 2991 if (!*str) 2992 break; 2993 2994 base = 10; 2995 is_sign = false; 2996 2997 switch (*fmt++) { 2998 case 'c': 2999 { 3000 char *s = (char *)va_arg(args, char*); 3001 if (field_width == -1) 3002 field_width = 1; 3003 do { 3004 *s++ = *str++; 3005 } while (--field_width > 0 && *str); 3006 num++; 3007 } 3008 continue; 3009 case 's': 3010 { 3011 char *s = (char *)va_arg(args, char *); 3012 if (field_width == -1) 3013 field_width = SHRT_MAX; 3014 /* first, skip leading white space in buffer */ 3015 str = skip_spaces(str); 3016 3017 /* now copy until next white space */ 3018 while (*str && !isspace(*str) && field_width--) 3019 *s++ = *str++; 3020 *s = '\0'; 3021 num++; 3022 } 3023 continue; 3024 /* 3025 * Warning: This implementation of the '[' conversion specifier 3026 * deviates from its glibc counterpart in the following ways: 3027 * (1) It does NOT support ranges i.e. '-' is NOT a special 3028 * character 3029 * (2) It cannot match the closing bracket ']' itself 3030 * (3) A field width is required 3031 * (4) '%*[' (discard matching input) is currently not supported 3032 * 3033 * Example usage: 3034 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3035 * buf1, buf2, buf3); 3036 * if (ret < 3) 3037 * // etc.. 3038 */ 3039 case '[': 3040 { 3041 char *s = (char *)va_arg(args, char *); 3042 DECLARE_BITMAP(set, 256) = {0}; 3043 unsigned int len = 0; 3044 bool negate = (*fmt == '^'); 3045 3046 /* field width is required */ 3047 if (field_width == -1) 3048 return num; 3049 3050 if (negate) 3051 ++fmt; 3052 3053 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3054 set_bit((u8)*fmt, set); 3055 3056 /* no ']' or no character set found */ 3057 if (!*fmt || !len) 3058 return num; 3059 ++fmt; 3060 3061 if (negate) { 3062 bitmap_complement(set, set, 256); 3063 /* exclude null '\0' byte */ 3064 clear_bit(0, set); 3065 } 3066 3067 /* match must be non-empty */ 3068 if (!test_bit((u8)*str, set)) 3069 return num; 3070 3071 while (test_bit((u8)*str, set) && field_width--) 3072 *s++ = *str++; 3073 *s = '\0'; 3074 ++num; 3075 } 3076 continue; 3077 case 'o': 3078 base = 8; 3079 break; 3080 case 'x': 3081 case 'X': 3082 base = 16; 3083 break; 3084 case 'i': 3085 base = 0; 3086 case 'd': 3087 is_sign = true; 3088 case 'u': 3089 break; 3090 case '%': 3091 /* looking for '%' in str */ 3092 if (*str++ != '%') 3093 return num; 3094 continue; 3095 default: 3096 /* invalid format; stop here */ 3097 return num; 3098 } 3099 3100 /* have some sort of integer conversion. 3101 * first, skip white space in buffer. 3102 */ 3103 str = skip_spaces(str); 3104 3105 digit = *str; 3106 if (is_sign && digit == '-') 3107 digit = *(str + 1); 3108 3109 if (!digit 3110 || (base == 16 && !isxdigit(digit)) 3111 || (base == 10 && !isdigit(digit)) 3112 || (base == 8 && (!isdigit(digit) || digit > '7')) 3113 || (base == 0 && !isdigit(digit))) 3114 break; 3115 3116 if (is_sign) 3117 val.s = qualifier != 'L' ? 3118 simple_strtol(str, &next, base) : 3119 simple_strtoll(str, &next, base); 3120 else 3121 val.u = qualifier != 'L' ? 3122 simple_strtoul(str, &next, base) : 3123 simple_strtoull(str, &next, base); 3124 3125 if (field_width > 0 && next - str > field_width) { 3126 if (base == 0) 3127 _parse_integer_fixup_radix(str, &base); 3128 while (next - str > field_width) { 3129 if (is_sign) 3130 val.s = div_s64(val.s, base); 3131 else 3132 val.u = div_u64(val.u, base); 3133 --next; 3134 } 3135 } 3136 3137 switch (qualifier) { 3138 case 'H': /* that's 'hh' in format */ 3139 if (is_sign) 3140 *va_arg(args, signed char *) = val.s; 3141 else 3142 *va_arg(args, unsigned char *) = val.u; 3143 break; 3144 case 'h': 3145 if (is_sign) 3146 *va_arg(args, short *) = val.s; 3147 else 3148 *va_arg(args, unsigned short *) = val.u; 3149 break; 3150 case 'l': 3151 if (is_sign) 3152 *va_arg(args, long *) = val.s; 3153 else 3154 *va_arg(args, unsigned long *) = val.u; 3155 break; 3156 case 'L': 3157 if (is_sign) 3158 *va_arg(args, long long *) = val.s; 3159 else 3160 *va_arg(args, unsigned long long *) = val.u; 3161 break; 3162 case 'z': 3163 *va_arg(args, size_t *) = val.u; 3164 break; 3165 default: 3166 if (is_sign) 3167 *va_arg(args, int *) = val.s; 3168 else 3169 *va_arg(args, unsigned int *) = val.u; 3170 break; 3171 } 3172 num++; 3173 3174 if (!next) 3175 break; 3176 str = next; 3177 } 3178 3179 return num; 3180 } 3181 EXPORT_SYMBOL(vsscanf); 3182 3183 /** 3184 * sscanf - Unformat a buffer into a list of arguments 3185 * @buf: input buffer 3186 * @fmt: formatting of buffer 3187 * @...: resulting arguments 3188 */ 3189 int sscanf(const char *buf, const char *fmt, ...) 3190 { 3191 va_list args; 3192 int i; 3193 3194 va_start(args, fmt); 3195 i = vsscanf(buf, fmt, args); 3196 va_end(args); 3197 3198 return i; 3199 } 3200 EXPORT_SYMBOL(sscanf); 3201