1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/lib/vsprintf.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 */ 7 8 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ 9 /* 10 * Wirzenius wrote this portably, Torvalds fucked it up :-) 11 */ 12 13 /* 14 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com> 15 * - changed to provide snprintf and vsnprintf functions 16 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> 17 * - scnprintf and vscnprintf 18 */ 19 20 #include <linux/stdarg.h> 21 #include <linux/build_bug.h> 22 #include <linux/clk.h> 23 #include <linux/clk-provider.h> 24 #include <linux/errname.h> 25 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */ 26 #include <linux/types.h> 27 #include <linux/string.h> 28 #include <linux/ctype.h> 29 #include <linux/kernel.h> 30 #include <linux/kallsyms.h> 31 #include <linux/math64.h> 32 #include <linux/uaccess.h> 33 #include <linux/ioport.h> 34 #include <linux/dcache.h> 35 #include <linux/cred.h> 36 #include <linux/rtc.h> 37 #include <linux/sprintf.h> 38 #include <linux/time.h> 39 #include <linux/uuid.h> 40 #include <linux/of.h> 41 #include <net/addrconf.h> 42 #include <linux/siphash.h> 43 #include <linux/compiler.h> 44 #include <linux/property.h> 45 #include <linux/notifier.h> 46 #ifdef CONFIG_BLOCK 47 #include <linux/blkdev.h> 48 #endif 49 50 #include "../mm/internal.h" /* For the trace_print_flags arrays */ 51 52 #include <asm/page.h> /* for PAGE_SIZE */ 53 #include <asm/byteorder.h> /* cpu_to_le16 */ 54 #include <asm/unaligned.h> 55 56 #include <linux/string_helpers.h> 57 #include "kstrtox.h" 58 59 /* Disable pointer hashing if requested */ 60 bool no_hash_pointers __ro_after_init; 61 EXPORT_SYMBOL_GPL(no_hash_pointers); 62 simple_strntoull(const char * startp,size_t max_chars,char ** endp,unsigned int base)63 static noinline unsigned long long simple_strntoull(const char *startp, size_t max_chars, char **endp, unsigned int base) 64 { 65 const char *cp; 66 unsigned long long result = 0ULL; 67 size_t prefix_chars; 68 unsigned int rv; 69 70 cp = _parse_integer_fixup_radix(startp, &base); 71 prefix_chars = cp - startp; 72 if (prefix_chars < max_chars) { 73 rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); 74 /* FIXME */ 75 cp += (rv & ~KSTRTOX_OVERFLOW); 76 } else { 77 /* Field too short for prefix + digit, skip over without converting */ 78 cp = startp + max_chars; 79 } 80 81 if (endp) 82 *endp = (char *)cp; 83 84 return result; 85 } 86 87 /** 88 * simple_strtoull - convert a string to an unsigned long long 89 * @cp: The start of the string 90 * @endp: A pointer to the end of the parsed string will be placed here 91 * @base: The number base to use 92 * 93 * This function has caveats. Please use kstrtoull instead. 94 */ 95 noinline simple_strtoull(const char * cp,char ** endp,unsigned int base)96 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 97 { 98 return simple_strntoull(cp, INT_MAX, endp, base); 99 } 100 EXPORT_SYMBOL(simple_strtoull); 101 102 /** 103 * simple_strtoul - convert a string to an unsigned long 104 * @cp: The start of the string 105 * @endp: A pointer to the end of the parsed string will be placed here 106 * @base: The number base to use 107 * 108 * This function has caveats. Please use kstrtoul instead. 109 */ simple_strtoul(const char * cp,char ** endp,unsigned int base)110 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 111 { 112 return simple_strtoull(cp, endp, base); 113 } 114 EXPORT_SYMBOL(simple_strtoul); 115 116 /** 117 * simple_strtol - convert a string to a signed long 118 * @cp: The start of the string 119 * @endp: A pointer to the end of the parsed string will be placed here 120 * @base: The number base to use 121 * 122 * This function has caveats. Please use kstrtol instead. 123 */ simple_strtol(const char * cp,char ** endp,unsigned int base)124 long simple_strtol(const char *cp, char **endp, unsigned int base) 125 { 126 if (*cp == '-') 127 return -simple_strtoul(cp + 1, endp, base); 128 129 return simple_strtoul(cp, endp, base); 130 } 131 EXPORT_SYMBOL(simple_strtol); 132 simple_strntoll(const char * cp,size_t max_chars,char ** endp,unsigned int base)133 static long long simple_strntoll(const char *cp, size_t max_chars, char **endp, 134 unsigned int base) 135 { 136 /* 137 * simple_strntoull() safely handles receiving max_chars==0 in the 138 * case cp[0] == '-' && max_chars == 1. 139 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 140 * and the content of *cp is irrelevant. 141 */ 142 if (*cp == '-' && max_chars > 0) 143 return -simple_strntoull(cp + 1, max_chars - 1, endp, base); 144 145 return simple_strntoull(cp, max_chars, endp, base); 146 } 147 148 /** 149 * simple_strtoll - convert a string to a signed long long 150 * @cp: The start of the string 151 * @endp: A pointer to the end of the parsed string will be placed here 152 * @base: The number base to use 153 * 154 * This function has caveats. Please use kstrtoll instead. 155 */ simple_strtoll(const char * cp,char ** endp,unsigned int base)156 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 157 { 158 return simple_strntoll(cp, INT_MAX, endp, base); 159 } 160 EXPORT_SYMBOL(simple_strtoll); 161 162 static noinline_for_stack skip_atoi(const char ** s)163 int skip_atoi(const char **s) 164 { 165 int i = 0; 166 167 do { 168 i = i*10 + *((*s)++) - '0'; 169 } while (isdigit(**s)); 170 171 return i; 172 } 173 174 /* 175 * Decimal conversion is by far the most typical, and is used for 176 * /proc and /sys data. This directly impacts e.g. top performance 177 * with many processes running. We optimize it for speed by emitting 178 * two characters at a time, using a 200 byte lookup table. This 179 * roughly halves the number of multiplications compared to computing 180 * the digits one at a time. Implementation strongly inspired by the 181 * previous version, which in turn used ideas described at 182 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 183 * from the author, Douglas W. Jones). 184 * 185 * It turns out there is precisely one 26 bit fixed-point 186 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 187 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 188 * range happens to be somewhat larger (x <= 1073741898), but that's 189 * irrelevant for our purpose. 190 * 191 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 192 * need a 32x32->64 bit multiply, so we simply use the same constant. 193 * 194 * For dividing a number in the range [100, 10^4-1] by 100, there are 195 * several options. The simplest is (x * 0x147b) >> 19, which is valid 196 * for all x <= 43698. 197 */ 198 199 static const u16 decpair[100] = { 200 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 201 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 202 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 203 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 204 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 205 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 206 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 207 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 208 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 209 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 210 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 211 #undef _ 212 }; 213 214 /* 215 * This will print a single '0' even if r == 0, since we would 216 * immediately jump to out_r where two 0s would be written but only 217 * one of them accounted for in buf. This is needed by ip4_string 218 * below. All other callers pass a non-zero value of r. 219 */ 220 static noinline_for_stack put_dec_trunc8(char * buf,unsigned r)221 char *put_dec_trunc8(char *buf, unsigned r) 222 { 223 unsigned q; 224 225 /* 1 <= r < 10^8 */ 226 if (r < 100) 227 goto out_r; 228 229 /* 100 <= r < 10^8 */ 230 q = (r * (u64)0x28f5c29) >> 32; 231 *((u16 *)buf) = decpair[r - 100*q]; 232 buf += 2; 233 234 /* 1 <= q < 10^6 */ 235 if (q < 100) 236 goto out_q; 237 238 /* 100 <= q < 10^6 */ 239 r = (q * (u64)0x28f5c29) >> 32; 240 *((u16 *)buf) = decpair[q - 100*r]; 241 buf += 2; 242 243 /* 1 <= r < 10^4 */ 244 if (r < 100) 245 goto out_r; 246 247 /* 100 <= r < 10^4 */ 248 q = (r * 0x147b) >> 19; 249 *((u16 *)buf) = decpair[r - 100*q]; 250 buf += 2; 251 out_q: 252 /* 1 <= q < 100 */ 253 r = q; 254 out_r: 255 /* 1 <= r < 100 */ 256 *((u16 *)buf) = decpair[r]; 257 buf += r < 10 ? 1 : 2; 258 return buf; 259 } 260 261 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 262 static noinline_for_stack put_dec_full8(char * buf,unsigned r)263 char *put_dec_full8(char *buf, unsigned r) 264 { 265 unsigned q; 266 267 /* 0 <= r < 10^8 */ 268 q = (r * (u64)0x28f5c29) >> 32; 269 *((u16 *)buf) = decpair[r - 100*q]; 270 buf += 2; 271 272 /* 0 <= q < 10^6 */ 273 r = (q * (u64)0x28f5c29) >> 32; 274 *((u16 *)buf) = decpair[q - 100*r]; 275 buf += 2; 276 277 /* 0 <= r < 10^4 */ 278 q = (r * 0x147b) >> 19; 279 *((u16 *)buf) = decpair[r - 100*q]; 280 buf += 2; 281 282 /* 0 <= q < 100 */ 283 *((u16 *)buf) = decpair[q]; 284 buf += 2; 285 return buf; 286 } 287 288 static noinline_for_stack put_dec(char * buf,unsigned long long n)289 char *put_dec(char *buf, unsigned long long n) 290 { 291 if (n >= 100*1000*1000) 292 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 293 /* 1 <= n <= 1.6e11 */ 294 if (n >= 100*1000*1000) 295 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 296 /* 1 <= n < 1e8 */ 297 return put_dec_trunc8(buf, n); 298 } 299 300 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 301 302 static void put_dec_full4(char * buf,unsigned r)303 put_dec_full4(char *buf, unsigned r) 304 { 305 unsigned q; 306 307 /* 0 <= r < 10^4 */ 308 q = (r * 0x147b) >> 19; 309 *((u16 *)buf) = decpair[r - 100*q]; 310 buf += 2; 311 /* 0 <= q < 100 */ 312 *((u16 *)buf) = decpair[q]; 313 } 314 315 /* 316 * Call put_dec_full4 on x % 10000, return x / 10000. 317 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 318 * holds for all x < 1,128,869,999. The largest value this 319 * helper will ever be asked to convert is 1,125,520,955. 320 * (second call in the put_dec code, assuming n is all-ones). 321 */ 322 static noinline_for_stack put_dec_helper4(char * buf,unsigned x)323 unsigned put_dec_helper4(char *buf, unsigned x) 324 { 325 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 326 327 put_dec_full4(buf, x - q * 10000); 328 return q; 329 } 330 331 /* Based on code by Douglas W. Jones found at 332 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 333 * (with permission from the author). 334 * Performs no 64-bit division and hence should be fast on 32-bit machines. 335 */ 336 static put_dec(char * buf,unsigned long long n)337 char *put_dec(char *buf, unsigned long long n) 338 { 339 uint32_t d3, d2, d1, q, h; 340 341 if (n < 100*1000*1000) 342 return put_dec_trunc8(buf, n); 343 344 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 345 h = (n >> 32); 346 d2 = (h ) & 0xffff; 347 d3 = (h >> 16); /* implicit "& 0xffff" */ 348 349 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 350 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 351 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 352 q = put_dec_helper4(buf, q); 353 354 q += 7671 * d3 + 9496 * d2 + 6 * d1; 355 q = put_dec_helper4(buf+4, q); 356 357 q += 4749 * d3 + 42 * d2; 358 q = put_dec_helper4(buf+8, q); 359 360 q += 281 * d3; 361 buf += 12; 362 if (q) 363 buf = put_dec_trunc8(buf, q); 364 else while (buf[-1] == '0') 365 --buf; 366 367 return buf; 368 } 369 370 #endif 371 372 /* 373 * Convert passed number to decimal string. 374 * Returns the length of string. On buffer overflow, returns 0. 375 * 376 * If speed is not important, use snprintf(). It's easy to read the code. 377 */ num_to_str(char * buf,int size,unsigned long long num,unsigned int width)378 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 379 { 380 /* put_dec requires 2-byte alignment of the buffer. */ 381 char tmp[sizeof(num) * 3] __aligned(2); 382 int idx, len; 383 384 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 385 if (num <= 9) { 386 tmp[0] = '0' + num; 387 len = 1; 388 } else { 389 len = put_dec(tmp, num) - tmp; 390 } 391 392 if (len > size || width > size) 393 return 0; 394 395 if (width > len) { 396 width = width - len; 397 for (idx = 0; idx < width; idx++) 398 buf[idx] = ' '; 399 } else { 400 width = 0; 401 } 402 403 for (idx = 0; idx < len; ++idx) 404 buf[idx + width] = tmp[len - idx - 1]; 405 406 return len + width; 407 } 408 409 #define SIGN 1 /* unsigned/signed, must be 1 */ 410 #define LEFT 2 /* left justified */ 411 #define PLUS 4 /* show plus */ 412 #define SPACE 8 /* space if plus */ 413 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 414 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 415 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 416 417 static_assert(SIGN == 1); 418 static_assert(ZEROPAD == ('0' - ' ')); 419 static_assert(SMALL == ('a' ^ 'A')); 420 421 enum format_type { 422 FORMAT_TYPE_NONE, /* Just a string part */ 423 FORMAT_TYPE_WIDTH, 424 FORMAT_TYPE_PRECISION, 425 FORMAT_TYPE_CHAR, 426 FORMAT_TYPE_STR, 427 FORMAT_TYPE_PTR, 428 FORMAT_TYPE_PERCENT_CHAR, 429 FORMAT_TYPE_INVALID, 430 FORMAT_TYPE_LONG_LONG, 431 FORMAT_TYPE_ULONG, 432 FORMAT_TYPE_LONG, 433 FORMAT_TYPE_UBYTE, 434 FORMAT_TYPE_BYTE, 435 FORMAT_TYPE_USHORT, 436 FORMAT_TYPE_SHORT, 437 FORMAT_TYPE_UINT, 438 FORMAT_TYPE_INT, 439 FORMAT_TYPE_SIZE_T, 440 FORMAT_TYPE_PTRDIFF 441 }; 442 443 struct printf_spec { 444 unsigned int type:8; /* format_type enum */ 445 signed int field_width:24; /* width of output field */ 446 unsigned int flags:8; /* flags to number() */ 447 unsigned int base:8; /* number base, 8, 10 or 16 only */ 448 signed int precision:16; /* # of digits/chars */ 449 } __packed; 450 static_assert(sizeof(struct printf_spec) == 8); 451 452 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 453 #define PRECISION_MAX ((1 << 15) - 1) 454 455 static noinline_for_stack number(char * buf,char * end,unsigned long long num,struct printf_spec spec)456 char *number(char *buf, char *end, unsigned long long num, 457 struct printf_spec spec) 458 { 459 /* put_dec requires 2-byte alignment of the buffer. */ 460 char tmp[3 * sizeof(num)] __aligned(2); 461 char sign; 462 char locase; 463 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 464 int i; 465 bool is_zero = num == 0LL; 466 int field_width = spec.field_width; 467 int precision = spec.precision; 468 469 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 470 * produces same digits or (maybe lowercased) letters */ 471 locase = (spec.flags & SMALL); 472 if (spec.flags & LEFT) 473 spec.flags &= ~ZEROPAD; 474 sign = 0; 475 if (spec.flags & SIGN) { 476 if ((signed long long)num < 0) { 477 sign = '-'; 478 num = -(signed long long)num; 479 field_width--; 480 } else if (spec.flags & PLUS) { 481 sign = '+'; 482 field_width--; 483 } else if (spec.flags & SPACE) { 484 sign = ' '; 485 field_width--; 486 } 487 } 488 if (need_pfx) { 489 if (spec.base == 16) 490 field_width -= 2; 491 else if (!is_zero) 492 field_width--; 493 } 494 495 /* generate full string in tmp[], in reverse order */ 496 i = 0; 497 if (num < spec.base) 498 tmp[i++] = hex_asc_upper[num] | locase; 499 else if (spec.base != 10) { /* 8 or 16 */ 500 int mask = spec.base - 1; 501 int shift = 3; 502 503 if (spec.base == 16) 504 shift = 4; 505 do { 506 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 507 num >>= shift; 508 } while (num); 509 } else { /* base 10 */ 510 i = put_dec(tmp, num) - tmp; 511 } 512 513 /* printing 100 using %2d gives "100", not "00" */ 514 if (i > precision) 515 precision = i; 516 /* leading space padding */ 517 field_width -= precision; 518 if (!(spec.flags & (ZEROPAD | LEFT))) { 519 while (--field_width >= 0) { 520 if (buf < end) 521 *buf = ' '; 522 ++buf; 523 } 524 } 525 /* sign */ 526 if (sign) { 527 if (buf < end) 528 *buf = sign; 529 ++buf; 530 } 531 /* "0x" / "0" prefix */ 532 if (need_pfx) { 533 if (spec.base == 16 || !is_zero) { 534 if (buf < end) 535 *buf = '0'; 536 ++buf; 537 } 538 if (spec.base == 16) { 539 if (buf < end) 540 *buf = ('X' | locase); 541 ++buf; 542 } 543 } 544 /* zero or space padding */ 545 if (!(spec.flags & LEFT)) { 546 char c = ' ' + (spec.flags & ZEROPAD); 547 548 while (--field_width >= 0) { 549 if (buf < end) 550 *buf = c; 551 ++buf; 552 } 553 } 554 /* hmm even more zero padding? */ 555 while (i <= --precision) { 556 if (buf < end) 557 *buf = '0'; 558 ++buf; 559 } 560 /* actual digits of result */ 561 while (--i >= 0) { 562 if (buf < end) 563 *buf = tmp[i]; 564 ++buf; 565 } 566 /* trailing space padding */ 567 while (--field_width >= 0) { 568 if (buf < end) 569 *buf = ' '; 570 ++buf; 571 } 572 573 return buf; 574 } 575 576 static noinline_for_stack special_hex_number(char * buf,char * end,unsigned long long num,int size)577 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 578 { 579 struct printf_spec spec; 580 581 spec.type = FORMAT_TYPE_PTR; 582 spec.field_width = 2 + 2 * size; /* 0x + hex */ 583 spec.flags = SPECIAL | SMALL | ZEROPAD; 584 spec.base = 16; 585 spec.precision = -1; 586 587 return number(buf, end, num, spec); 588 } 589 move_right(char * buf,char * end,unsigned len,unsigned spaces)590 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 591 { 592 size_t size; 593 if (buf >= end) /* nowhere to put anything */ 594 return; 595 size = end - buf; 596 if (size <= spaces) { 597 memset(buf, ' ', size); 598 return; 599 } 600 if (len) { 601 if (len > size - spaces) 602 len = size - spaces; 603 memmove(buf + spaces, buf, len); 604 } 605 memset(buf, ' ', spaces); 606 } 607 608 /* 609 * Handle field width padding for a string. 610 * @buf: current buffer position 611 * @n: length of string 612 * @end: end of output buffer 613 * @spec: for field width and flags 614 * Returns: new buffer position after padding. 615 */ 616 static noinline_for_stack widen_string(char * buf,int n,char * end,struct printf_spec spec)617 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 618 { 619 unsigned spaces; 620 621 if (likely(n >= spec.field_width)) 622 return buf; 623 /* we want to pad the sucker */ 624 spaces = spec.field_width - n; 625 if (!(spec.flags & LEFT)) { 626 move_right(buf - n, end, n, spaces); 627 return buf + spaces; 628 } 629 while (spaces--) { 630 if (buf < end) 631 *buf = ' '; 632 ++buf; 633 } 634 return buf; 635 } 636 637 /* Handle string from a well known address. */ string_nocheck(char * buf,char * end,const char * s,struct printf_spec spec)638 static char *string_nocheck(char *buf, char *end, const char *s, 639 struct printf_spec spec) 640 { 641 int len = 0; 642 int lim = spec.precision; 643 644 while (lim--) { 645 char c = *s++; 646 if (!c) 647 break; 648 if (buf < end) 649 *buf = c; 650 ++buf; 651 ++len; 652 } 653 return widen_string(buf, len, end, spec); 654 } 655 err_ptr(char * buf,char * end,void * ptr,struct printf_spec spec)656 static char *err_ptr(char *buf, char *end, void *ptr, 657 struct printf_spec spec) 658 { 659 int err = PTR_ERR(ptr); 660 const char *sym = errname(err); 661 662 if (sym) 663 return string_nocheck(buf, end, sym, spec); 664 665 /* 666 * Somebody passed ERR_PTR(-1234) or some other non-existing 667 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 668 * printing it as its decimal representation. 669 */ 670 spec.flags |= SIGN; 671 spec.base = 10; 672 return number(buf, end, err, spec); 673 } 674 675 /* Be careful: error messages must fit into the given buffer. */ error_string(char * buf,char * end,const char * s,struct printf_spec spec)676 static char *error_string(char *buf, char *end, const char *s, 677 struct printf_spec spec) 678 { 679 /* 680 * Hard limit to avoid a completely insane messages. It actually 681 * works pretty well because most error messages are in 682 * the many pointer format modifiers. 683 */ 684 if (spec.precision == -1) 685 spec.precision = 2 * sizeof(void *); 686 687 return string_nocheck(buf, end, s, spec); 688 } 689 690 /* 691 * Do not call any complex external code here. Nested printk()/vsprintf() 692 * might cause infinite loops. Failures might break printk() and would 693 * be hard to debug. 694 */ check_pointer_msg(const void * ptr)695 static const char *check_pointer_msg(const void *ptr) 696 { 697 if (!ptr) 698 return "(null)"; 699 700 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 701 return "(efault)"; 702 703 return NULL; 704 } 705 check_pointer(char ** buf,char * end,const void * ptr,struct printf_spec spec)706 static int check_pointer(char **buf, char *end, const void *ptr, 707 struct printf_spec spec) 708 { 709 const char *err_msg; 710 711 err_msg = check_pointer_msg(ptr); 712 if (err_msg) { 713 *buf = error_string(*buf, end, err_msg, spec); 714 return -EFAULT; 715 } 716 717 return 0; 718 } 719 720 static noinline_for_stack string(char * buf,char * end,const char * s,struct printf_spec spec)721 char *string(char *buf, char *end, const char *s, 722 struct printf_spec spec) 723 { 724 if (check_pointer(&buf, end, s, spec)) 725 return buf; 726 727 return string_nocheck(buf, end, s, spec); 728 } 729 pointer_string(char * buf,char * end,const void * ptr,struct printf_spec spec)730 static char *pointer_string(char *buf, char *end, 731 const void *ptr, 732 struct printf_spec spec) 733 { 734 spec.base = 16; 735 spec.flags |= SMALL; 736 if (spec.field_width == -1) { 737 spec.field_width = 2 * sizeof(ptr); 738 spec.flags |= ZEROPAD; 739 } 740 741 return number(buf, end, (unsigned long int)ptr, spec); 742 } 743 744 /* Make pointers available for printing early in the boot sequence. */ 745 static int debug_boot_weak_hash __ro_after_init; 746 debug_boot_weak_hash_enable(char * str)747 static int __init debug_boot_weak_hash_enable(char *str) 748 { 749 debug_boot_weak_hash = 1; 750 pr_info("debug_boot_weak_hash enabled\n"); 751 return 0; 752 } 753 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 754 755 static bool filled_random_ptr_key __read_mostly; 756 static siphash_key_t ptr_key __read_mostly; 757 fill_ptr_key(struct notifier_block * nb,unsigned long action,void * data)758 static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) 759 { 760 get_random_bytes(&ptr_key, sizeof(ptr_key)); 761 762 /* Pairs with smp_rmb() before reading ptr_key. */ 763 smp_wmb(); 764 WRITE_ONCE(filled_random_ptr_key, true); 765 return NOTIFY_DONE; 766 } 767 vsprintf_init_hashval(void)768 static int __init vsprintf_init_hashval(void) 769 { 770 static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; 771 execute_with_initialized_rng(&fill_ptr_key_nb); 772 return 0; 773 } subsys_initcall(vsprintf_init_hashval)774 subsys_initcall(vsprintf_init_hashval) 775 776 /* Maps a pointer to a 32 bit unique identifier. */ 777 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 778 { 779 unsigned long hashval; 780 781 if (!READ_ONCE(filled_random_ptr_key)) 782 return -EBUSY; 783 784 /* Pairs with smp_wmb() after writing ptr_key. */ 785 smp_rmb(); 786 787 #ifdef CONFIG_64BIT 788 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 789 /* 790 * Mask off the first 32 bits, this makes explicit that we have 791 * modified the address (and 32 bits is plenty for a unique ID). 792 */ 793 hashval = hashval & 0xffffffff; 794 #else 795 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 796 #endif 797 *hashval_out = hashval; 798 return 0; 799 } 800 ptr_to_hashval(const void * ptr,unsigned long * hashval_out)801 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 802 { 803 return __ptr_to_hashval(ptr, hashval_out); 804 } 805 ptr_to_id(char * buf,char * end,const void * ptr,struct printf_spec spec)806 static char *ptr_to_id(char *buf, char *end, const void *ptr, 807 struct printf_spec spec) 808 { 809 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 810 unsigned long hashval; 811 int ret; 812 813 /* 814 * Print the real pointer value for NULL and error pointers, 815 * as they are not actual addresses. 816 */ 817 if (IS_ERR_OR_NULL(ptr)) 818 return pointer_string(buf, end, ptr, spec); 819 820 /* When debugging early boot use non-cryptographically secure hash. */ 821 if (unlikely(debug_boot_weak_hash)) { 822 hashval = hash_long((unsigned long)ptr, 32); 823 return pointer_string(buf, end, (const void *)hashval, spec); 824 } 825 826 ret = __ptr_to_hashval(ptr, &hashval); 827 if (ret) { 828 spec.field_width = 2 * sizeof(ptr); 829 /* string length must be less than default_width */ 830 return error_string(buf, end, str, spec); 831 } 832 833 return pointer_string(buf, end, (const void *)hashval, spec); 834 } 835 default_pointer(char * buf,char * end,const void * ptr,struct printf_spec spec)836 static char *default_pointer(char *buf, char *end, const void *ptr, 837 struct printf_spec spec) 838 { 839 /* 840 * default is to _not_ leak addresses, so hash before printing, 841 * unless no_hash_pointers is specified on the command line. 842 */ 843 if (unlikely(no_hash_pointers)) 844 return pointer_string(buf, end, ptr, spec); 845 846 return ptr_to_id(buf, end, ptr, spec); 847 } 848 849 int kptr_restrict __read_mostly; 850 851 static noinline_for_stack restricted_pointer(char * buf,char * end,const void * ptr,struct printf_spec spec)852 char *restricted_pointer(char *buf, char *end, const void *ptr, 853 struct printf_spec spec) 854 { 855 switch (kptr_restrict) { 856 case 0: 857 /* Handle as %p, hash and do _not_ leak addresses. */ 858 return default_pointer(buf, end, ptr, spec); 859 case 1: { 860 const struct cred *cred; 861 862 /* 863 * kptr_restrict==1 cannot be used in IRQ context 864 * because its test for CAP_SYSLOG would be meaningless. 865 */ 866 if (in_hardirq() || in_serving_softirq() || in_nmi()) { 867 if (spec.field_width == -1) 868 spec.field_width = 2 * sizeof(ptr); 869 return error_string(buf, end, "pK-error", spec); 870 } 871 872 /* 873 * Only print the real pointer value if the current 874 * process has CAP_SYSLOG and is running with the 875 * same credentials it started with. This is because 876 * access to files is checked at open() time, but %pK 877 * checks permission at read() time. We don't want to 878 * leak pointer values if a binary opens a file using 879 * %pK and then elevates privileges before reading it. 880 */ 881 cred = current_cred(); 882 if (!has_capability_noaudit(current, CAP_SYSLOG) || 883 !uid_eq(cred->euid, cred->uid) || 884 !gid_eq(cred->egid, cred->gid)) 885 ptr = NULL; 886 break; 887 } 888 case 2: 889 default: 890 /* Always print 0's for %pK */ 891 ptr = NULL; 892 break; 893 } 894 895 return pointer_string(buf, end, ptr, spec); 896 } 897 898 static noinline_for_stack dentry_name(char * buf,char * end,const struct dentry * d,struct printf_spec spec,const char * fmt)899 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 900 const char *fmt) 901 { 902 const char *array[4], *s; 903 const struct dentry *p; 904 int depth; 905 int i, n; 906 907 switch (fmt[1]) { 908 case '2': case '3': case '4': 909 depth = fmt[1] - '0'; 910 break; 911 default: 912 depth = 1; 913 } 914 915 rcu_read_lock(); 916 for (i = 0; i < depth; i++, d = p) { 917 if (check_pointer(&buf, end, d, spec)) { 918 rcu_read_unlock(); 919 return buf; 920 } 921 922 p = READ_ONCE(d->d_parent); 923 array[i] = READ_ONCE(d->d_name.name); 924 if (p == d) { 925 if (i) 926 array[i] = ""; 927 i++; 928 break; 929 } 930 } 931 s = array[--i]; 932 for (n = 0; n != spec.precision; n++, buf++) { 933 char c = *s++; 934 if (!c) { 935 if (!i) 936 break; 937 c = '/'; 938 s = array[--i]; 939 } 940 if (buf < end) 941 *buf = c; 942 } 943 rcu_read_unlock(); 944 return widen_string(buf, n, end, spec); 945 } 946 947 static noinline_for_stack file_dentry_name(char * buf,char * end,const struct file * f,struct printf_spec spec,const char * fmt)948 char *file_dentry_name(char *buf, char *end, const struct file *f, 949 struct printf_spec spec, const char *fmt) 950 { 951 if (check_pointer(&buf, end, f, spec)) 952 return buf; 953 954 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 955 } 956 #ifdef CONFIG_BLOCK 957 static noinline_for_stack bdev_name(char * buf,char * end,struct block_device * bdev,struct printf_spec spec,const char * fmt)958 char *bdev_name(char *buf, char *end, struct block_device *bdev, 959 struct printf_spec spec, const char *fmt) 960 { 961 struct gendisk *hd; 962 963 if (check_pointer(&buf, end, bdev, spec)) 964 return buf; 965 966 hd = bdev->bd_disk; 967 buf = string(buf, end, hd->disk_name, spec); 968 if (bdev->bd_partno) { 969 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 970 if (buf < end) 971 *buf = 'p'; 972 buf++; 973 } 974 buf = number(buf, end, bdev->bd_partno, spec); 975 } 976 return buf; 977 } 978 #endif 979 980 static noinline_for_stack symbol_string(char * buf,char * end,void * ptr,struct printf_spec spec,const char * fmt)981 char *symbol_string(char *buf, char *end, void *ptr, 982 struct printf_spec spec, const char *fmt) 983 { 984 unsigned long value; 985 #ifdef CONFIG_KALLSYMS 986 char sym[KSYM_SYMBOL_LEN]; 987 #endif 988 989 if (fmt[1] == 'R') 990 ptr = __builtin_extract_return_addr(ptr); 991 value = (unsigned long)ptr; 992 993 #ifdef CONFIG_KALLSYMS 994 if (*fmt == 'B' && fmt[1] == 'b') 995 sprint_backtrace_build_id(sym, value); 996 else if (*fmt == 'B') 997 sprint_backtrace(sym, value); 998 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 999 sprint_symbol_build_id(sym, value); 1000 else if (*fmt != 's') 1001 sprint_symbol(sym, value); 1002 else 1003 sprint_symbol_no_offset(sym, value); 1004 1005 return string_nocheck(buf, end, sym, spec); 1006 #else 1007 return special_hex_number(buf, end, value, sizeof(void *)); 1008 #endif 1009 } 1010 1011 static const struct printf_spec default_str_spec = { 1012 .field_width = -1, 1013 .precision = -1, 1014 }; 1015 1016 static const struct printf_spec default_flag_spec = { 1017 .base = 16, 1018 .precision = -1, 1019 .flags = SPECIAL | SMALL, 1020 }; 1021 1022 static const struct printf_spec default_dec_spec = { 1023 .base = 10, 1024 .precision = -1, 1025 }; 1026 1027 static const struct printf_spec default_dec02_spec = { 1028 .base = 10, 1029 .field_width = 2, 1030 .precision = -1, 1031 .flags = ZEROPAD, 1032 }; 1033 1034 static const struct printf_spec default_dec04_spec = { 1035 .base = 10, 1036 .field_width = 4, 1037 .precision = -1, 1038 .flags = ZEROPAD, 1039 }; 1040 1041 static noinline_for_stack resource_string(char * buf,char * end,struct resource * res,struct printf_spec spec,const char * fmt)1042 char *resource_string(char *buf, char *end, struct resource *res, 1043 struct printf_spec spec, const char *fmt) 1044 { 1045 #ifndef IO_RSRC_PRINTK_SIZE 1046 #define IO_RSRC_PRINTK_SIZE 6 1047 #endif 1048 1049 #ifndef MEM_RSRC_PRINTK_SIZE 1050 #define MEM_RSRC_PRINTK_SIZE 10 1051 #endif 1052 static const struct printf_spec io_spec = { 1053 .base = 16, 1054 .field_width = IO_RSRC_PRINTK_SIZE, 1055 .precision = -1, 1056 .flags = SPECIAL | SMALL | ZEROPAD, 1057 }; 1058 static const struct printf_spec mem_spec = { 1059 .base = 16, 1060 .field_width = MEM_RSRC_PRINTK_SIZE, 1061 .precision = -1, 1062 .flags = SPECIAL | SMALL | ZEROPAD, 1063 }; 1064 static const struct printf_spec bus_spec = { 1065 .base = 16, 1066 .field_width = 2, 1067 .precision = -1, 1068 .flags = SMALL | ZEROPAD, 1069 }; 1070 static const struct printf_spec str_spec = { 1071 .field_width = -1, 1072 .precision = 10, 1073 .flags = LEFT, 1074 }; 1075 1076 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1077 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1078 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1079 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1080 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1081 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1082 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1083 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1084 1085 char *p = sym, *pend = sym + sizeof(sym); 1086 int decode = (fmt[0] == 'R') ? 1 : 0; 1087 const struct printf_spec *specp; 1088 1089 if (check_pointer(&buf, end, res, spec)) 1090 return buf; 1091 1092 *p++ = '['; 1093 if (res->flags & IORESOURCE_IO) { 1094 p = string_nocheck(p, pend, "io ", str_spec); 1095 specp = &io_spec; 1096 } else if (res->flags & IORESOURCE_MEM) { 1097 p = string_nocheck(p, pend, "mem ", str_spec); 1098 specp = &mem_spec; 1099 } else if (res->flags & IORESOURCE_IRQ) { 1100 p = string_nocheck(p, pend, "irq ", str_spec); 1101 specp = &default_dec_spec; 1102 } else if (res->flags & IORESOURCE_DMA) { 1103 p = string_nocheck(p, pend, "dma ", str_spec); 1104 specp = &default_dec_spec; 1105 } else if (res->flags & IORESOURCE_BUS) { 1106 p = string_nocheck(p, pend, "bus ", str_spec); 1107 specp = &bus_spec; 1108 } else { 1109 p = string_nocheck(p, pend, "??? ", str_spec); 1110 specp = &mem_spec; 1111 decode = 0; 1112 } 1113 if (decode && res->flags & IORESOURCE_UNSET) { 1114 p = string_nocheck(p, pend, "size ", str_spec); 1115 p = number(p, pend, resource_size(res), *specp); 1116 } else { 1117 p = number(p, pend, res->start, *specp); 1118 if (res->start != res->end) { 1119 *p++ = '-'; 1120 p = number(p, pend, res->end, *specp); 1121 } 1122 } 1123 if (decode) { 1124 if (res->flags & IORESOURCE_MEM_64) 1125 p = string_nocheck(p, pend, " 64bit", str_spec); 1126 if (res->flags & IORESOURCE_PREFETCH) 1127 p = string_nocheck(p, pend, " pref", str_spec); 1128 if (res->flags & IORESOURCE_WINDOW) 1129 p = string_nocheck(p, pend, " window", str_spec); 1130 if (res->flags & IORESOURCE_DISABLED) 1131 p = string_nocheck(p, pend, " disabled", str_spec); 1132 } else { 1133 p = string_nocheck(p, pend, " flags ", str_spec); 1134 p = number(p, pend, res->flags, default_flag_spec); 1135 } 1136 *p++ = ']'; 1137 *p = '\0'; 1138 1139 return string_nocheck(buf, end, sym, spec); 1140 } 1141 1142 static noinline_for_stack hex_string(char * buf,char * end,u8 * addr,struct printf_spec spec,const char * fmt)1143 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1144 const char *fmt) 1145 { 1146 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1147 negative value, fallback to the default */ 1148 char separator; 1149 1150 if (spec.field_width == 0) 1151 /* nothing to print */ 1152 return buf; 1153 1154 if (check_pointer(&buf, end, addr, spec)) 1155 return buf; 1156 1157 switch (fmt[1]) { 1158 case 'C': 1159 separator = ':'; 1160 break; 1161 case 'D': 1162 separator = '-'; 1163 break; 1164 case 'N': 1165 separator = 0; 1166 break; 1167 default: 1168 separator = ' '; 1169 break; 1170 } 1171 1172 if (spec.field_width > 0) 1173 len = min_t(int, spec.field_width, 64); 1174 1175 for (i = 0; i < len; ++i) { 1176 if (buf < end) 1177 *buf = hex_asc_hi(addr[i]); 1178 ++buf; 1179 if (buf < end) 1180 *buf = hex_asc_lo(addr[i]); 1181 ++buf; 1182 1183 if (separator && i != len - 1) { 1184 if (buf < end) 1185 *buf = separator; 1186 ++buf; 1187 } 1188 } 1189 1190 return buf; 1191 } 1192 1193 static noinline_for_stack bitmap_string(char * buf,char * end,const unsigned long * bitmap,struct printf_spec spec,const char * fmt)1194 char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, 1195 struct printf_spec spec, const char *fmt) 1196 { 1197 const int CHUNKSZ = 32; 1198 int nr_bits = max_t(int, spec.field_width, 0); 1199 int i, chunksz; 1200 bool first = true; 1201 1202 if (check_pointer(&buf, end, bitmap, spec)) 1203 return buf; 1204 1205 /* reused to print numbers */ 1206 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1207 1208 chunksz = nr_bits & (CHUNKSZ - 1); 1209 if (chunksz == 0) 1210 chunksz = CHUNKSZ; 1211 1212 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1213 for (; i >= 0; i -= CHUNKSZ) { 1214 u32 chunkmask, val; 1215 int word, bit; 1216 1217 chunkmask = ((1ULL << chunksz) - 1); 1218 word = i / BITS_PER_LONG; 1219 bit = i % BITS_PER_LONG; 1220 val = (bitmap[word] >> bit) & chunkmask; 1221 1222 if (!first) { 1223 if (buf < end) 1224 *buf = ','; 1225 buf++; 1226 } 1227 first = false; 1228 1229 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1230 buf = number(buf, end, val, spec); 1231 1232 chunksz = CHUNKSZ; 1233 } 1234 return buf; 1235 } 1236 1237 static noinline_for_stack bitmap_list_string(char * buf,char * end,const unsigned long * bitmap,struct printf_spec spec,const char * fmt)1238 char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, 1239 struct printf_spec spec, const char *fmt) 1240 { 1241 int nr_bits = max_t(int, spec.field_width, 0); 1242 bool first = true; 1243 int rbot, rtop; 1244 1245 if (check_pointer(&buf, end, bitmap, spec)) 1246 return buf; 1247 1248 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1249 if (!first) { 1250 if (buf < end) 1251 *buf = ','; 1252 buf++; 1253 } 1254 first = false; 1255 1256 buf = number(buf, end, rbot, default_dec_spec); 1257 if (rtop == rbot + 1) 1258 continue; 1259 1260 if (buf < end) 1261 *buf = '-'; 1262 buf = number(++buf, end, rtop - 1, default_dec_spec); 1263 } 1264 return buf; 1265 } 1266 1267 static noinline_for_stack mac_address_string(char * buf,char * end,u8 * addr,struct printf_spec spec,const char * fmt)1268 char *mac_address_string(char *buf, char *end, u8 *addr, 1269 struct printf_spec spec, const char *fmt) 1270 { 1271 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1272 char *p = mac_addr; 1273 int i; 1274 char separator; 1275 bool reversed = false; 1276 1277 if (check_pointer(&buf, end, addr, spec)) 1278 return buf; 1279 1280 switch (fmt[1]) { 1281 case 'F': 1282 separator = '-'; 1283 break; 1284 1285 case 'R': 1286 reversed = true; 1287 fallthrough; 1288 1289 default: 1290 separator = ':'; 1291 break; 1292 } 1293 1294 for (i = 0; i < 6; i++) { 1295 if (reversed) 1296 p = hex_byte_pack(p, addr[5 - i]); 1297 else 1298 p = hex_byte_pack(p, addr[i]); 1299 1300 if (fmt[0] == 'M' && i != 5) 1301 *p++ = separator; 1302 } 1303 *p = '\0'; 1304 1305 return string_nocheck(buf, end, mac_addr, spec); 1306 } 1307 1308 static noinline_for_stack ip4_string(char * p,const u8 * addr,const char * fmt)1309 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1310 { 1311 int i; 1312 bool leading_zeros = (fmt[0] == 'i'); 1313 int index; 1314 int step; 1315 1316 switch (fmt[2]) { 1317 case 'h': 1318 #ifdef __BIG_ENDIAN 1319 index = 0; 1320 step = 1; 1321 #else 1322 index = 3; 1323 step = -1; 1324 #endif 1325 break; 1326 case 'l': 1327 index = 3; 1328 step = -1; 1329 break; 1330 case 'n': 1331 case 'b': 1332 default: 1333 index = 0; 1334 step = 1; 1335 break; 1336 } 1337 for (i = 0; i < 4; i++) { 1338 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1339 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1340 if (leading_zeros) { 1341 if (digits < 3) 1342 *p++ = '0'; 1343 if (digits < 2) 1344 *p++ = '0'; 1345 } 1346 /* reverse the digits in the quad */ 1347 while (digits--) 1348 *p++ = temp[digits]; 1349 if (i < 3) 1350 *p++ = '.'; 1351 index += step; 1352 } 1353 *p = '\0'; 1354 1355 return p; 1356 } 1357 1358 static noinline_for_stack ip6_compressed_string(char * p,const char * addr)1359 char *ip6_compressed_string(char *p, const char *addr) 1360 { 1361 int i, j, range; 1362 unsigned char zerolength[8]; 1363 int longest = 1; 1364 int colonpos = -1; 1365 u16 word; 1366 u8 hi, lo; 1367 bool needcolon = false; 1368 bool useIPv4; 1369 struct in6_addr in6; 1370 1371 memcpy(&in6, addr, sizeof(struct in6_addr)); 1372 1373 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1374 1375 memset(zerolength, 0, sizeof(zerolength)); 1376 1377 if (useIPv4) 1378 range = 6; 1379 else 1380 range = 8; 1381 1382 /* find position of longest 0 run */ 1383 for (i = 0; i < range; i++) { 1384 for (j = i; j < range; j++) { 1385 if (in6.s6_addr16[j] != 0) 1386 break; 1387 zerolength[i]++; 1388 } 1389 } 1390 for (i = 0; i < range; i++) { 1391 if (zerolength[i] > longest) { 1392 longest = zerolength[i]; 1393 colonpos = i; 1394 } 1395 } 1396 if (longest == 1) /* don't compress a single 0 */ 1397 colonpos = -1; 1398 1399 /* emit address */ 1400 for (i = 0; i < range; i++) { 1401 if (i == colonpos) { 1402 if (needcolon || i == 0) 1403 *p++ = ':'; 1404 *p++ = ':'; 1405 needcolon = false; 1406 i += longest - 1; 1407 continue; 1408 } 1409 if (needcolon) { 1410 *p++ = ':'; 1411 needcolon = false; 1412 } 1413 /* hex u16 without leading 0s */ 1414 word = ntohs(in6.s6_addr16[i]); 1415 hi = word >> 8; 1416 lo = word & 0xff; 1417 if (hi) { 1418 if (hi > 0x0f) 1419 p = hex_byte_pack(p, hi); 1420 else 1421 *p++ = hex_asc_lo(hi); 1422 p = hex_byte_pack(p, lo); 1423 } 1424 else if (lo > 0x0f) 1425 p = hex_byte_pack(p, lo); 1426 else 1427 *p++ = hex_asc_lo(lo); 1428 needcolon = true; 1429 } 1430 1431 if (useIPv4) { 1432 if (needcolon) 1433 *p++ = ':'; 1434 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1435 } 1436 *p = '\0'; 1437 1438 return p; 1439 } 1440 1441 static noinline_for_stack ip6_string(char * p,const char * addr,const char * fmt)1442 char *ip6_string(char *p, const char *addr, const char *fmt) 1443 { 1444 int i; 1445 1446 for (i = 0; i < 8; i++) { 1447 p = hex_byte_pack(p, *addr++); 1448 p = hex_byte_pack(p, *addr++); 1449 if (fmt[0] == 'I' && i != 7) 1450 *p++ = ':'; 1451 } 1452 *p = '\0'; 1453 1454 return p; 1455 } 1456 1457 static noinline_for_stack ip6_addr_string(char * buf,char * end,const u8 * addr,struct printf_spec spec,const char * fmt)1458 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1459 struct printf_spec spec, const char *fmt) 1460 { 1461 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1462 1463 if (fmt[0] == 'I' && fmt[2] == 'c') 1464 ip6_compressed_string(ip6_addr, addr); 1465 else 1466 ip6_string(ip6_addr, addr, fmt); 1467 1468 return string_nocheck(buf, end, ip6_addr, spec); 1469 } 1470 1471 static noinline_for_stack ip4_addr_string(char * buf,char * end,const u8 * addr,struct printf_spec spec,const char * fmt)1472 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1473 struct printf_spec spec, const char *fmt) 1474 { 1475 char ip4_addr[sizeof("255.255.255.255")]; 1476 1477 ip4_string(ip4_addr, addr, fmt); 1478 1479 return string_nocheck(buf, end, ip4_addr, spec); 1480 } 1481 1482 static noinline_for_stack ip6_addr_string_sa(char * buf,char * end,const struct sockaddr_in6 * sa,struct printf_spec spec,const char * fmt)1483 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1484 struct printf_spec spec, const char *fmt) 1485 { 1486 bool have_p = false, have_s = false, have_f = false, have_c = false; 1487 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1488 sizeof(":12345") + sizeof("/123456789") + 1489 sizeof("%1234567890")]; 1490 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1491 const u8 *addr = (const u8 *) &sa->sin6_addr; 1492 char fmt6[2] = { fmt[0], '6' }; 1493 u8 off = 0; 1494 1495 fmt++; 1496 while (isalpha(*++fmt)) { 1497 switch (*fmt) { 1498 case 'p': 1499 have_p = true; 1500 break; 1501 case 'f': 1502 have_f = true; 1503 break; 1504 case 's': 1505 have_s = true; 1506 break; 1507 case 'c': 1508 have_c = true; 1509 break; 1510 } 1511 } 1512 1513 if (have_p || have_s || have_f) { 1514 *p = '['; 1515 off = 1; 1516 } 1517 1518 if (fmt6[0] == 'I' && have_c) 1519 p = ip6_compressed_string(ip6_addr + off, addr); 1520 else 1521 p = ip6_string(ip6_addr + off, addr, fmt6); 1522 1523 if (have_p || have_s || have_f) 1524 *p++ = ']'; 1525 1526 if (have_p) { 1527 *p++ = ':'; 1528 p = number(p, pend, ntohs(sa->sin6_port), spec); 1529 } 1530 if (have_f) { 1531 *p++ = '/'; 1532 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1533 IPV6_FLOWINFO_MASK), spec); 1534 } 1535 if (have_s) { 1536 *p++ = '%'; 1537 p = number(p, pend, sa->sin6_scope_id, spec); 1538 } 1539 *p = '\0'; 1540 1541 return string_nocheck(buf, end, ip6_addr, spec); 1542 } 1543 1544 static noinline_for_stack ip4_addr_string_sa(char * buf,char * end,const struct sockaddr_in * sa,struct printf_spec spec,const char * fmt)1545 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1546 struct printf_spec spec, const char *fmt) 1547 { 1548 bool have_p = false; 1549 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1550 char *pend = ip4_addr + sizeof(ip4_addr); 1551 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1552 char fmt4[3] = { fmt[0], '4', 0 }; 1553 1554 fmt++; 1555 while (isalpha(*++fmt)) { 1556 switch (*fmt) { 1557 case 'p': 1558 have_p = true; 1559 break; 1560 case 'h': 1561 case 'l': 1562 case 'n': 1563 case 'b': 1564 fmt4[2] = *fmt; 1565 break; 1566 } 1567 } 1568 1569 p = ip4_string(ip4_addr, addr, fmt4); 1570 if (have_p) { 1571 *p++ = ':'; 1572 p = number(p, pend, ntohs(sa->sin_port), spec); 1573 } 1574 *p = '\0'; 1575 1576 return string_nocheck(buf, end, ip4_addr, spec); 1577 } 1578 1579 static noinline_for_stack ip_addr_string(char * buf,char * end,const void * ptr,struct printf_spec spec,const char * fmt)1580 char *ip_addr_string(char *buf, char *end, const void *ptr, 1581 struct printf_spec spec, const char *fmt) 1582 { 1583 char *err_fmt_msg; 1584 1585 if (check_pointer(&buf, end, ptr, spec)) 1586 return buf; 1587 1588 switch (fmt[1]) { 1589 case '6': 1590 return ip6_addr_string(buf, end, ptr, spec, fmt); 1591 case '4': 1592 return ip4_addr_string(buf, end, ptr, spec, fmt); 1593 case 'S': { 1594 const union { 1595 struct sockaddr raw; 1596 struct sockaddr_in v4; 1597 struct sockaddr_in6 v6; 1598 } *sa = ptr; 1599 1600 switch (sa->raw.sa_family) { 1601 case AF_INET: 1602 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1603 case AF_INET6: 1604 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1605 default: 1606 return error_string(buf, end, "(einval)", spec); 1607 }} 1608 } 1609 1610 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1611 return error_string(buf, end, err_fmt_msg, spec); 1612 } 1613 1614 static noinline_for_stack escaped_string(char * buf,char * end,u8 * addr,struct printf_spec spec,const char * fmt)1615 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1616 const char *fmt) 1617 { 1618 bool found = true; 1619 int count = 1; 1620 unsigned int flags = 0; 1621 int len; 1622 1623 if (spec.field_width == 0) 1624 return buf; /* nothing to print */ 1625 1626 if (check_pointer(&buf, end, addr, spec)) 1627 return buf; 1628 1629 do { 1630 switch (fmt[count++]) { 1631 case 'a': 1632 flags |= ESCAPE_ANY; 1633 break; 1634 case 'c': 1635 flags |= ESCAPE_SPECIAL; 1636 break; 1637 case 'h': 1638 flags |= ESCAPE_HEX; 1639 break; 1640 case 'n': 1641 flags |= ESCAPE_NULL; 1642 break; 1643 case 'o': 1644 flags |= ESCAPE_OCTAL; 1645 break; 1646 case 'p': 1647 flags |= ESCAPE_NP; 1648 break; 1649 case 's': 1650 flags |= ESCAPE_SPACE; 1651 break; 1652 default: 1653 found = false; 1654 break; 1655 } 1656 } while (found); 1657 1658 if (!flags) 1659 flags = ESCAPE_ANY_NP; 1660 1661 len = spec.field_width < 0 ? 1 : spec.field_width; 1662 1663 /* 1664 * string_escape_mem() writes as many characters as it can to 1665 * the given buffer, and returns the total size of the output 1666 * had the buffer been big enough. 1667 */ 1668 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1669 1670 return buf; 1671 } 1672 va_format(char * buf,char * end,struct va_format * va_fmt,struct printf_spec spec,const char * fmt)1673 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1674 struct printf_spec spec, const char *fmt) 1675 { 1676 va_list va; 1677 1678 if (check_pointer(&buf, end, va_fmt, spec)) 1679 return buf; 1680 1681 va_copy(va, *va_fmt->va); 1682 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1683 va_end(va); 1684 1685 return buf; 1686 } 1687 1688 static noinline_for_stack uuid_string(char * buf,char * end,const u8 * addr,struct printf_spec spec,const char * fmt)1689 char *uuid_string(char *buf, char *end, const u8 *addr, 1690 struct printf_spec spec, const char *fmt) 1691 { 1692 char uuid[UUID_STRING_LEN + 1]; 1693 char *p = uuid; 1694 int i; 1695 const u8 *index = uuid_index; 1696 bool uc = false; 1697 1698 if (check_pointer(&buf, end, addr, spec)) 1699 return buf; 1700 1701 switch (*(++fmt)) { 1702 case 'L': 1703 uc = true; 1704 fallthrough; 1705 case 'l': 1706 index = guid_index; 1707 break; 1708 case 'B': 1709 uc = true; 1710 break; 1711 } 1712 1713 for (i = 0; i < 16; i++) { 1714 if (uc) 1715 p = hex_byte_pack_upper(p, addr[index[i]]); 1716 else 1717 p = hex_byte_pack(p, addr[index[i]]); 1718 switch (i) { 1719 case 3: 1720 case 5: 1721 case 7: 1722 case 9: 1723 *p++ = '-'; 1724 break; 1725 } 1726 } 1727 1728 *p = 0; 1729 1730 return string_nocheck(buf, end, uuid, spec); 1731 } 1732 1733 static noinline_for_stack netdev_bits(char * buf,char * end,const void * addr,struct printf_spec spec,const char * fmt)1734 char *netdev_bits(char *buf, char *end, const void *addr, 1735 struct printf_spec spec, const char *fmt) 1736 { 1737 unsigned long long num; 1738 int size; 1739 1740 if (check_pointer(&buf, end, addr, spec)) 1741 return buf; 1742 1743 switch (fmt[1]) { 1744 case 'F': 1745 num = *(const netdev_features_t *)addr; 1746 size = sizeof(netdev_features_t); 1747 break; 1748 default: 1749 return error_string(buf, end, "(%pN?)", spec); 1750 } 1751 1752 return special_hex_number(buf, end, num, size); 1753 } 1754 1755 static noinline_for_stack fourcc_string(char * buf,char * end,const u32 * fourcc,struct printf_spec spec,const char * fmt)1756 char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1757 struct printf_spec spec, const char *fmt) 1758 { 1759 char output[sizeof("0123 little-endian (0x01234567)")]; 1760 char *p = output; 1761 unsigned int i; 1762 u32 orig, val; 1763 1764 if (fmt[1] != 'c' || fmt[2] != 'c') 1765 return error_string(buf, end, "(%p4?)", spec); 1766 1767 if (check_pointer(&buf, end, fourcc, spec)) 1768 return buf; 1769 1770 orig = get_unaligned(fourcc); 1771 val = orig & ~BIT(31); 1772 1773 for (i = 0; i < sizeof(u32); i++) { 1774 unsigned char c = val >> (i * 8); 1775 1776 /* Print non-control ASCII characters as-is, dot otherwise */ 1777 *p++ = isascii(c) && isprint(c) ? c : '.'; 1778 } 1779 1780 *p++ = ' '; 1781 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1782 p += strlen(p); 1783 1784 *p++ = ' '; 1785 *p++ = '('; 1786 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1787 *p++ = ')'; 1788 *p = '\0'; 1789 1790 return string(buf, end, output, spec); 1791 } 1792 1793 static noinline_for_stack address_val(char * buf,char * end,const void * addr,struct printf_spec spec,const char * fmt)1794 char *address_val(char *buf, char *end, const void *addr, 1795 struct printf_spec spec, const char *fmt) 1796 { 1797 unsigned long long num; 1798 int size; 1799 1800 if (check_pointer(&buf, end, addr, spec)) 1801 return buf; 1802 1803 switch (fmt[1]) { 1804 case 'd': 1805 num = *(const dma_addr_t *)addr; 1806 size = sizeof(dma_addr_t); 1807 break; 1808 case 'p': 1809 default: 1810 num = *(const phys_addr_t *)addr; 1811 size = sizeof(phys_addr_t); 1812 break; 1813 } 1814 1815 return special_hex_number(buf, end, num, size); 1816 } 1817 1818 static noinline_for_stack date_str(char * buf,char * end,const struct rtc_time * tm,bool r)1819 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1820 { 1821 int year = tm->tm_year + (r ? 0 : 1900); 1822 int mon = tm->tm_mon + (r ? 0 : 1); 1823 1824 buf = number(buf, end, year, default_dec04_spec); 1825 if (buf < end) 1826 *buf = '-'; 1827 buf++; 1828 1829 buf = number(buf, end, mon, default_dec02_spec); 1830 if (buf < end) 1831 *buf = '-'; 1832 buf++; 1833 1834 return number(buf, end, tm->tm_mday, default_dec02_spec); 1835 } 1836 1837 static noinline_for_stack time_str(char * buf,char * end,const struct rtc_time * tm,bool r)1838 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1839 { 1840 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1841 if (buf < end) 1842 *buf = ':'; 1843 buf++; 1844 1845 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1846 if (buf < end) 1847 *buf = ':'; 1848 buf++; 1849 1850 return number(buf, end, tm->tm_sec, default_dec02_spec); 1851 } 1852 1853 static noinline_for_stack rtc_str(char * buf,char * end,const struct rtc_time * tm,struct printf_spec spec,const char * fmt)1854 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1855 struct printf_spec spec, const char *fmt) 1856 { 1857 bool have_t = true, have_d = true; 1858 bool raw = false, iso8601_separator = true; 1859 bool found = true; 1860 int count = 2; 1861 1862 if (check_pointer(&buf, end, tm, spec)) 1863 return buf; 1864 1865 switch (fmt[count]) { 1866 case 'd': 1867 have_t = false; 1868 count++; 1869 break; 1870 case 't': 1871 have_d = false; 1872 count++; 1873 break; 1874 } 1875 1876 do { 1877 switch (fmt[count++]) { 1878 case 'r': 1879 raw = true; 1880 break; 1881 case 's': 1882 iso8601_separator = false; 1883 break; 1884 default: 1885 found = false; 1886 break; 1887 } 1888 } while (found); 1889 1890 if (have_d) 1891 buf = date_str(buf, end, tm, raw); 1892 if (have_d && have_t) { 1893 if (buf < end) 1894 *buf = iso8601_separator ? 'T' : ' '; 1895 buf++; 1896 } 1897 if (have_t) 1898 buf = time_str(buf, end, tm, raw); 1899 1900 return buf; 1901 } 1902 1903 static noinline_for_stack time64_str(char * buf,char * end,const time64_t time,struct printf_spec spec,const char * fmt)1904 char *time64_str(char *buf, char *end, const time64_t time, 1905 struct printf_spec spec, const char *fmt) 1906 { 1907 struct rtc_time rtc_time; 1908 struct tm tm; 1909 1910 time64_to_tm(time, 0, &tm); 1911 1912 rtc_time.tm_sec = tm.tm_sec; 1913 rtc_time.tm_min = tm.tm_min; 1914 rtc_time.tm_hour = tm.tm_hour; 1915 rtc_time.tm_mday = tm.tm_mday; 1916 rtc_time.tm_mon = tm.tm_mon; 1917 rtc_time.tm_year = tm.tm_year; 1918 rtc_time.tm_wday = tm.tm_wday; 1919 rtc_time.tm_yday = tm.tm_yday; 1920 1921 rtc_time.tm_isdst = 0; 1922 1923 return rtc_str(buf, end, &rtc_time, spec, fmt); 1924 } 1925 1926 static noinline_for_stack time_and_date(char * buf,char * end,void * ptr,struct printf_spec spec,const char * fmt)1927 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1928 const char *fmt) 1929 { 1930 switch (fmt[1]) { 1931 case 'R': 1932 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1933 case 'T': 1934 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 1935 default: 1936 return error_string(buf, end, "(%pt?)", spec); 1937 } 1938 } 1939 1940 static noinline_for_stack clock(char * buf,char * end,struct clk * clk,struct printf_spec spec,const char * fmt)1941 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1942 const char *fmt) 1943 { 1944 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1945 return error_string(buf, end, "(%pC?)", spec); 1946 1947 if (check_pointer(&buf, end, clk, spec)) 1948 return buf; 1949 1950 switch (fmt[1]) { 1951 case 'n': 1952 default: 1953 #ifdef CONFIG_COMMON_CLK 1954 return string(buf, end, __clk_get_name(clk), spec); 1955 #else 1956 return ptr_to_id(buf, end, clk, spec); 1957 #endif 1958 } 1959 } 1960 1961 static format_flags(char * buf,char * end,unsigned long flags,const struct trace_print_flags * names)1962 char *format_flags(char *buf, char *end, unsigned long flags, 1963 const struct trace_print_flags *names) 1964 { 1965 unsigned long mask; 1966 1967 for ( ; flags && names->name; names++) { 1968 mask = names->mask; 1969 if ((flags & mask) != mask) 1970 continue; 1971 1972 buf = string(buf, end, names->name, default_str_spec); 1973 1974 flags &= ~mask; 1975 if (flags) { 1976 if (buf < end) 1977 *buf = '|'; 1978 buf++; 1979 } 1980 } 1981 1982 if (flags) 1983 buf = number(buf, end, flags, default_flag_spec); 1984 1985 return buf; 1986 } 1987 1988 struct page_flags_fields { 1989 int width; 1990 int shift; 1991 int mask; 1992 const struct printf_spec *spec; 1993 const char *name; 1994 }; 1995 1996 static const struct page_flags_fields pff[] = { 1997 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 1998 &default_dec_spec, "section"}, 1999 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2000 &default_dec_spec, "node"}, 2001 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2002 &default_dec_spec, "zone"}, 2003 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2004 &default_flag_spec, "lastcpupid"}, 2005 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2006 &default_flag_spec, "kasantag"}, 2007 }; 2008 2009 static format_page_flags(char * buf,char * end,unsigned long flags)2010 char *format_page_flags(char *buf, char *end, unsigned long flags) 2011 { 2012 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2013 bool append = false; 2014 int i; 2015 2016 buf = number(buf, end, flags, default_flag_spec); 2017 if (buf < end) 2018 *buf = '('; 2019 buf++; 2020 2021 /* Page flags from the main area. */ 2022 if (main_flags) { 2023 buf = format_flags(buf, end, main_flags, pageflag_names); 2024 append = true; 2025 } 2026 2027 /* Page flags from the fields area */ 2028 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2029 /* Skip undefined fields. */ 2030 if (!pff[i].width) 2031 continue; 2032 2033 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2034 if (append) { 2035 if (buf < end) 2036 *buf = '|'; 2037 buf++; 2038 } 2039 2040 buf = string(buf, end, pff[i].name, default_str_spec); 2041 if (buf < end) 2042 *buf = '='; 2043 buf++; 2044 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2045 *pff[i].spec); 2046 2047 append = true; 2048 } 2049 if (buf < end) 2050 *buf = ')'; 2051 buf++; 2052 2053 return buf; 2054 } 2055 2056 static format_page_type(char * buf,char * end,unsigned int page_type)2057 char *format_page_type(char *buf, char *end, unsigned int page_type) 2058 { 2059 buf = number(buf, end, page_type, default_flag_spec); 2060 2061 if (buf < end) 2062 *buf = '('; 2063 buf++; 2064 2065 if (page_type_has_type(page_type)) 2066 buf = format_flags(buf, end, ~page_type, pagetype_names); 2067 2068 if (buf < end) 2069 *buf = ')'; 2070 buf++; 2071 2072 return buf; 2073 } 2074 2075 static noinline_for_stack flags_string(char * buf,char * end,void * flags_ptr,struct printf_spec spec,const char * fmt)2076 char *flags_string(char *buf, char *end, void *flags_ptr, 2077 struct printf_spec spec, const char *fmt) 2078 { 2079 unsigned long flags; 2080 const struct trace_print_flags *names; 2081 2082 if (check_pointer(&buf, end, flags_ptr, spec)) 2083 return buf; 2084 2085 switch (fmt[1]) { 2086 case 'p': 2087 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2088 case 't': 2089 return format_page_type(buf, end, *(unsigned int *)flags_ptr); 2090 case 'v': 2091 flags = *(unsigned long *)flags_ptr; 2092 names = vmaflag_names; 2093 break; 2094 case 'g': 2095 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2096 names = gfpflag_names; 2097 break; 2098 default: 2099 return error_string(buf, end, "(%pG?)", spec); 2100 } 2101 2102 return format_flags(buf, end, flags, names); 2103 } 2104 2105 static noinline_for_stack fwnode_full_name_string(struct fwnode_handle * fwnode,char * buf,char * end)2106 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2107 char *end) 2108 { 2109 int depth; 2110 2111 /* Loop starting from the root node to the current node. */ 2112 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2113 /* 2114 * Only get a reference for other nodes (i.e. parent nodes). 2115 * fwnode refcount may be 0 here. 2116 */ 2117 struct fwnode_handle *__fwnode = depth ? 2118 fwnode_get_nth_parent(fwnode, depth) : fwnode; 2119 2120 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2121 default_str_spec); 2122 buf = string(buf, end, fwnode_get_name(__fwnode), 2123 default_str_spec); 2124 2125 if (depth) 2126 fwnode_handle_put(__fwnode); 2127 } 2128 2129 return buf; 2130 } 2131 2132 static noinline_for_stack device_node_string(char * buf,char * end,struct device_node * dn,struct printf_spec spec,const char * fmt)2133 char *device_node_string(char *buf, char *end, struct device_node *dn, 2134 struct printf_spec spec, const char *fmt) 2135 { 2136 char tbuf[sizeof("xxxx") + 1]; 2137 const char *p; 2138 int ret; 2139 char *buf_start = buf; 2140 struct property *prop; 2141 bool has_mult, pass; 2142 2143 struct printf_spec str_spec = spec; 2144 str_spec.field_width = -1; 2145 2146 if (fmt[0] != 'F') 2147 return error_string(buf, end, "(%pO?)", spec); 2148 2149 if (!IS_ENABLED(CONFIG_OF)) 2150 return error_string(buf, end, "(%pOF?)", spec); 2151 2152 if (check_pointer(&buf, end, dn, spec)) 2153 return buf; 2154 2155 /* simple case without anything any more format specifiers */ 2156 fmt++; 2157 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2158 fmt = "f"; 2159 2160 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2161 int precision; 2162 if (pass) { 2163 if (buf < end) 2164 *buf = ':'; 2165 buf++; 2166 } 2167 2168 switch (*fmt) { 2169 case 'f': /* full_name */ 2170 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2171 end); 2172 break; 2173 case 'n': /* name */ 2174 p = fwnode_get_name(of_fwnode_handle(dn)); 2175 precision = str_spec.precision; 2176 str_spec.precision = strchrnul(p, '@') - p; 2177 buf = string(buf, end, p, str_spec); 2178 str_spec.precision = precision; 2179 break; 2180 case 'p': /* phandle */ 2181 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2182 break; 2183 case 'P': /* path-spec */ 2184 p = fwnode_get_name(of_fwnode_handle(dn)); 2185 if (!p[1]) 2186 p = "/"; 2187 buf = string(buf, end, p, str_spec); 2188 break; 2189 case 'F': /* flags */ 2190 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2191 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2192 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2193 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2194 tbuf[4] = 0; 2195 buf = string_nocheck(buf, end, tbuf, str_spec); 2196 break; 2197 case 'c': /* major compatible string */ 2198 ret = of_property_read_string(dn, "compatible", &p); 2199 if (!ret) 2200 buf = string(buf, end, p, str_spec); 2201 break; 2202 case 'C': /* full compatible string */ 2203 has_mult = false; 2204 of_property_for_each_string(dn, "compatible", prop, p) { 2205 if (has_mult) 2206 buf = string_nocheck(buf, end, ",", str_spec); 2207 buf = string_nocheck(buf, end, "\"", str_spec); 2208 buf = string(buf, end, p, str_spec); 2209 buf = string_nocheck(buf, end, "\"", str_spec); 2210 2211 has_mult = true; 2212 } 2213 break; 2214 default: 2215 break; 2216 } 2217 } 2218 2219 return widen_string(buf, buf - buf_start, end, spec); 2220 } 2221 2222 static noinline_for_stack fwnode_string(char * buf,char * end,struct fwnode_handle * fwnode,struct printf_spec spec,const char * fmt)2223 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2224 struct printf_spec spec, const char *fmt) 2225 { 2226 struct printf_spec str_spec = spec; 2227 char *buf_start = buf; 2228 2229 str_spec.field_width = -1; 2230 2231 if (*fmt != 'w') 2232 return error_string(buf, end, "(%pf?)", spec); 2233 2234 if (check_pointer(&buf, end, fwnode, spec)) 2235 return buf; 2236 2237 fmt++; 2238 2239 switch (*fmt) { 2240 case 'P': /* name */ 2241 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2242 break; 2243 case 'f': /* full_name */ 2244 default: 2245 buf = fwnode_full_name_string(fwnode, buf, end); 2246 break; 2247 } 2248 2249 return widen_string(buf, buf - buf_start, end, spec); 2250 } 2251 no_hash_pointers_enable(char * str)2252 int __init no_hash_pointers_enable(char *str) 2253 { 2254 if (no_hash_pointers) 2255 return 0; 2256 2257 no_hash_pointers = true; 2258 2259 pr_warn("**********************************************************\n"); 2260 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2261 pr_warn("** **\n"); 2262 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2263 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2264 pr_warn("** might reduce the security of your system. **\n"); 2265 pr_warn("** **\n"); 2266 pr_warn("** If you see this message and you are not debugging **\n"); 2267 pr_warn("** the kernel, report this immediately to your system **\n"); 2268 pr_warn("** administrator! **\n"); 2269 pr_warn("** **\n"); 2270 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2271 pr_warn("**********************************************************\n"); 2272 2273 return 0; 2274 } 2275 early_param("no_hash_pointers", no_hash_pointers_enable); 2276 2277 /* Used for Rust formatting ('%pA'). */ 2278 char *rust_fmt_argument(char *buf, char *end, void *ptr); 2279 2280 /* 2281 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2282 * by an extra set of alphanumeric characters that are extended format 2283 * specifiers. 2284 * 2285 * Please update scripts/checkpatch.pl when adding/removing conversion 2286 * characters. (Search for "check for vsprintf extension"). 2287 * 2288 * Right now we handle: 2289 * 2290 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2291 * - 's' For symbolic direct pointers (or function descriptors) without offset 2292 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2293 * - 'S[R]b' as above with module build ID (for use in backtraces) 2294 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2295 * %ps and %pS. Be careful when re-using these specifiers. 2296 * - 'B' For backtraced symbolic direct pointers with offset 2297 * - 'Bb' as above with module build ID (for use in backtraces) 2298 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2299 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2300 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2301 * width which must be explicitly specified either as part of the 2302 * format string '%32b[l]' or through '%*b[l]', [l] selects 2303 * range-list format instead of hex format 2304 * - 'M' For a 6-byte MAC address, it prints the address in the 2305 * usual colon-separated hex notation 2306 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2307 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2308 * with a dash-separated hex notation 2309 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2310 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2311 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2312 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2313 * [S][pfs] 2314 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2315 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2316 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2317 * IPv6 omits the colons (01020304...0f) 2318 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2319 * [S][pfs] 2320 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2321 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2322 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2323 * - 'I[6S]c' for IPv6 addresses printed as specified by 2324 * https://tools.ietf.org/html/rfc5952 2325 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2326 * of the following flags (see string_escape_mem() for the 2327 * details): 2328 * a - ESCAPE_ANY 2329 * c - ESCAPE_SPECIAL 2330 * h - ESCAPE_HEX 2331 * n - ESCAPE_NULL 2332 * o - ESCAPE_OCTAL 2333 * p - ESCAPE_NP 2334 * s - ESCAPE_SPACE 2335 * By default ESCAPE_ANY_NP is used. 2336 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2337 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2338 * Options for %pU are: 2339 * b big endian lower case hex (default) 2340 * B big endian UPPER case hex 2341 * l little endian lower case hex 2342 * L little endian UPPER case hex 2343 * big endian output byte order is: 2344 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2345 * little endian output byte order is: 2346 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2347 * - 'V' For a struct va_format which contains a format string * and va_list *, 2348 * call vsnprintf(->format, *->va_list). 2349 * Implements a "recursive vsnprintf". 2350 * Do not use this feature without some mechanism to verify the 2351 * correctness of the format string and va_list arguments. 2352 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2353 * Use only for procfs, sysfs and similar files, not printk(); please 2354 * read the documentation (path below) first. 2355 * - 'NF' For a netdev_features_t 2356 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2357 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2358 * a certain separator (' ' by default): 2359 * C colon 2360 * D dash 2361 * N no separator 2362 * The maximum supported length is 64 bytes of the input. Consider 2363 * to use print_hex_dump() for the larger input. 2364 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2365 * (default assumed to be phys_addr_t, passed by reference) 2366 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2367 * - 'D[234]' Same as 'd' but for a struct file 2368 * - 'g' For block_device name (gendisk + partition number) 2369 * - 't[RT][dt][r][s]' For time and date as represented by: 2370 * R struct rtc_time 2371 * T time64_t 2372 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2373 * (legacy clock framework) of the clock 2374 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2375 * (legacy clock framework) of the clock 2376 * - 'G' For flags to be printed as a collection of symbolic strings that would 2377 * construct the specific value. Supported flags given by option: 2378 * p page flags (see struct page) given as pointer to unsigned long 2379 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2380 * v vma flags (VM_*) given as pointer to unsigned long 2381 * - 'OF[fnpPcCF]' For a device tree object 2382 * Without any optional arguments prints the full_name 2383 * f device node full_name 2384 * n device node name 2385 * p device node phandle 2386 * P device node path spec (name + @unit) 2387 * F device node flags 2388 * c major compatible string 2389 * C full compatible string 2390 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2391 * Without an option prints the full name of the node 2392 * f full name 2393 * P node name, including a possible unit address 2394 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2395 * Please read the documentation (path below) before using! 2396 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2397 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2398 * or user (u) memory to probe, and: 2399 * s a string, equivalent to "%s" on direct vsnprintf() use 2400 * 2401 * ** When making changes please also update: 2402 * Documentation/core-api/printk-formats.rst 2403 * 2404 * Note: The default behaviour (unadorned %p) is to hash the address, 2405 * rendering it useful as a unique identifier. 2406 * 2407 * There is also a '%pA' format specifier, but it is only intended to be used 2408 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2409 * See rust/kernel/print.rs for details. 2410 */ 2411 static noinline_for_stack pointer(const char * fmt,char * buf,char * end,void * ptr,struct printf_spec spec)2412 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2413 struct printf_spec spec) 2414 { 2415 switch (*fmt) { 2416 case 'S': 2417 case 's': 2418 ptr = dereference_symbol_descriptor(ptr); 2419 fallthrough; 2420 case 'B': 2421 return symbol_string(buf, end, ptr, spec, fmt); 2422 case 'R': 2423 case 'r': 2424 return resource_string(buf, end, ptr, spec, fmt); 2425 case 'h': 2426 return hex_string(buf, end, ptr, spec, fmt); 2427 case 'b': 2428 switch (fmt[1]) { 2429 case 'l': 2430 return bitmap_list_string(buf, end, ptr, spec, fmt); 2431 default: 2432 return bitmap_string(buf, end, ptr, spec, fmt); 2433 } 2434 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2435 case 'm': /* Contiguous: 000102030405 */ 2436 /* [mM]F (FDDI) */ 2437 /* [mM]R (Reverse order; Bluetooth) */ 2438 return mac_address_string(buf, end, ptr, spec, fmt); 2439 case 'I': /* Formatted IP supported 2440 * 4: 1.2.3.4 2441 * 6: 0001:0203:...:0708 2442 * 6c: 1::708 or 1::1.2.3.4 2443 */ 2444 case 'i': /* Contiguous: 2445 * 4: 001.002.003.004 2446 * 6: 000102...0f 2447 */ 2448 return ip_addr_string(buf, end, ptr, spec, fmt); 2449 case 'E': 2450 return escaped_string(buf, end, ptr, spec, fmt); 2451 case 'U': 2452 return uuid_string(buf, end, ptr, spec, fmt); 2453 case 'V': 2454 return va_format(buf, end, ptr, spec, fmt); 2455 case 'K': 2456 return restricted_pointer(buf, end, ptr, spec); 2457 case 'N': 2458 return netdev_bits(buf, end, ptr, spec, fmt); 2459 case '4': 2460 return fourcc_string(buf, end, ptr, spec, fmt); 2461 case 'a': 2462 return address_val(buf, end, ptr, spec, fmt); 2463 case 'd': 2464 return dentry_name(buf, end, ptr, spec, fmt); 2465 case 't': 2466 return time_and_date(buf, end, ptr, spec, fmt); 2467 case 'C': 2468 return clock(buf, end, ptr, spec, fmt); 2469 case 'D': 2470 return file_dentry_name(buf, end, ptr, spec, fmt); 2471 #ifdef CONFIG_BLOCK 2472 case 'g': 2473 return bdev_name(buf, end, ptr, spec, fmt); 2474 #endif 2475 2476 case 'G': 2477 return flags_string(buf, end, ptr, spec, fmt); 2478 case 'O': 2479 return device_node_string(buf, end, ptr, spec, fmt + 1); 2480 case 'f': 2481 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2482 case 'A': 2483 if (!IS_ENABLED(CONFIG_RUST)) { 2484 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2485 return error_string(buf, end, "(%pA?)", spec); 2486 } 2487 return rust_fmt_argument(buf, end, ptr); 2488 case 'x': 2489 return pointer_string(buf, end, ptr, spec); 2490 case 'e': 2491 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2492 if (!IS_ERR(ptr)) 2493 return default_pointer(buf, end, ptr, spec); 2494 return err_ptr(buf, end, ptr, spec); 2495 case 'u': 2496 case 'k': 2497 switch (fmt[1]) { 2498 case 's': 2499 return string(buf, end, ptr, spec); 2500 default: 2501 return error_string(buf, end, "(einval)", spec); 2502 } 2503 default: 2504 return default_pointer(buf, end, ptr, spec); 2505 } 2506 } 2507 2508 /* 2509 * Helper function to decode printf style format. 2510 * Each call decode a token from the format and return the 2511 * number of characters read (or likely the delta where it wants 2512 * to go on the next call). 2513 * The decoded token is returned through the parameters 2514 * 2515 * 'h', 'l', or 'L' for integer fields 2516 * 'z' support added 23/7/1999 S.H. 2517 * 'z' changed to 'Z' --davidm 1/25/99 2518 * 'Z' changed to 'z' --adobriyan 2017-01-25 2519 * 't' added for ptrdiff_t 2520 * 2521 * @fmt: the format string 2522 * @type of the token returned 2523 * @flags: various flags such as +, -, # tokens.. 2524 * @field_width: overwritten width 2525 * @base: base of the number (octal, hex, ...) 2526 * @precision: precision of a number 2527 * @qualifier: qualifier of a number (long, size_t, ...) 2528 */ 2529 static noinline_for_stack format_decode(const char * fmt,struct printf_spec * spec)2530 int format_decode(const char *fmt, struct printf_spec *spec) 2531 { 2532 const char *start = fmt; 2533 char qualifier; 2534 2535 /* we finished early by reading the field width */ 2536 if (spec->type == FORMAT_TYPE_WIDTH) { 2537 if (spec->field_width < 0) { 2538 spec->field_width = -spec->field_width; 2539 spec->flags |= LEFT; 2540 } 2541 spec->type = FORMAT_TYPE_NONE; 2542 goto precision; 2543 } 2544 2545 /* we finished early by reading the precision */ 2546 if (spec->type == FORMAT_TYPE_PRECISION) { 2547 if (spec->precision < 0) 2548 spec->precision = 0; 2549 2550 spec->type = FORMAT_TYPE_NONE; 2551 goto qualifier; 2552 } 2553 2554 /* By default */ 2555 spec->type = FORMAT_TYPE_NONE; 2556 2557 for (; *fmt ; ++fmt) { 2558 if (*fmt == '%') 2559 break; 2560 } 2561 2562 /* Return the current non-format string */ 2563 if (fmt != start || !*fmt) 2564 return fmt - start; 2565 2566 /* Process flags */ 2567 spec->flags = 0; 2568 2569 while (1) { /* this also skips first '%' */ 2570 bool found = true; 2571 2572 ++fmt; 2573 2574 switch (*fmt) { 2575 case '-': spec->flags |= LEFT; break; 2576 case '+': spec->flags |= PLUS; break; 2577 case ' ': spec->flags |= SPACE; break; 2578 case '#': spec->flags |= SPECIAL; break; 2579 case '0': spec->flags |= ZEROPAD; break; 2580 default: found = false; 2581 } 2582 2583 if (!found) 2584 break; 2585 } 2586 2587 /* get field width */ 2588 spec->field_width = -1; 2589 2590 if (isdigit(*fmt)) 2591 spec->field_width = skip_atoi(&fmt); 2592 else if (*fmt == '*') { 2593 /* it's the next argument */ 2594 spec->type = FORMAT_TYPE_WIDTH; 2595 return ++fmt - start; 2596 } 2597 2598 precision: 2599 /* get the precision */ 2600 spec->precision = -1; 2601 if (*fmt == '.') { 2602 ++fmt; 2603 if (isdigit(*fmt)) { 2604 spec->precision = skip_atoi(&fmt); 2605 if (spec->precision < 0) 2606 spec->precision = 0; 2607 } else if (*fmt == '*') { 2608 /* it's the next argument */ 2609 spec->type = FORMAT_TYPE_PRECISION; 2610 return ++fmt - start; 2611 } 2612 } 2613 2614 qualifier: 2615 /* get the conversion qualifier */ 2616 qualifier = 0; 2617 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2618 *fmt == 'z' || *fmt == 't') { 2619 qualifier = *fmt++; 2620 if (unlikely(qualifier == *fmt)) { 2621 if (qualifier == 'l') { 2622 qualifier = 'L'; 2623 ++fmt; 2624 } else if (qualifier == 'h') { 2625 qualifier = 'H'; 2626 ++fmt; 2627 } 2628 } 2629 } 2630 2631 /* default base */ 2632 spec->base = 10; 2633 switch (*fmt) { 2634 case 'c': 2635 spec->type = FORMAT_TYPE_CHAR; 2636 return ++fmt - start; 2637 2638 case 's': 2639 spec->type = FORMAT_TYPE_STR; 2640 return ++fmt - start; 2641 2642 case 'p': 2643 spec->type = FORMAT_TYPE_PTR; 2644 return ++fmt - start; 2645 2646 case '%': 2647 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2648 return ++fmt - start; 2649 2650 /* integer number formats - set up the flags and "break" */ 2651 case 'o': 2652 spec->base = 8; 2653 break; 2654 2655 case 'x': 2656 spec->flags |= SMALL; 2657 fallthrough; 2658 2659 case 'X': 2660 spec->base = 16; 2661 break; 2662 2663 case 'd': 2664 case 'i': 2665 spec->flags |= SIGN; 2666 break; 2667 case 'u': 2668 break; 2669 2670 case 'n': 2671 /* 2672 * Since %n poses a greater security risk than 2673 * utility, treat it as any other invalid or 2674 * unsupported format specifier. 2675 */ 2676 fallthrough; 2677 2678 default: 2679 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2680 spec->type = FORMAT_TYPE_INVALID; 2681 return fmt - start; 2682 } 2683 2684 if (qualifier == 'L') 2685 spec->type = FORMAT_TYPE_LONG_LONG; 2686 else if (qualifier == 'l') { 2687 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2688 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2689 } else if (qualifier == 'z') { 2690 spec->type = FORMAT_TYPE_SIZE_T; 2691 } else if (qualifier == 't') { 2692 spec->type = FORMAT_TYPE_PTRDIFF; 2693 } else if (qualifier == 'H') { 2694 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2695 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2696 } else if (qualifier == 'h') { 2697 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2698 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2699 } else { 2700 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2701 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2702 } 2703 2704 return ++fmt - start; 2705 } 2706 2707 static void set_field_width(struct printf_spec * spec,int width)2708 set_field_width(struct printf_spec *spec, int width) 2709 { 2710 spec->field_width = width; 2711 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2712 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2713 } 2714 } 2715 2716 static void set_precision(struct printf_spec * spec,int prec)2717 set_precision(struct printf_spec *spec, int prec) 2718 { 2719 spec->precision = prec; 2720 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2721 spec->precision = clamp(prec, 0, PRECISION_MAX); 2722 } 2723 } 2724 2725 /** 2726 * vsnprintf - Format a string and place it in a buffer 2727 * @buf: The buffer to place the result into 2728 * @size: The size of the buffer, including the trailing null space 2729 * @fmt: The format string to use 2730 * @args: Arguments for the format string 2731 * 2732 * This function generally follows C99 vsnprintf, but has some 2733 * extensions and a few limitations: 2734 * 2735 * - ``%n`` is unsupported 2736 * - ``%p*`` is handled by pointer() 2737 * 2738 * See pointer() or Documentation/core-api/printk-formats.rst for more 2739 * extensive description. 2740 * 2741 * **Please update the documentation in both places when making changes** 2742 * 2743 * The return value is the number of characters which would 2744 * be generated for the given input, excluding the trailing 2745 * '\0', as per ISO C99. If you want to have the exact 2746 * number of characters written into @buf as return value 2747 * (not including the trailing '\0'), use vscnprintf(). If the 2748 * return is greater than or equal to @size, the resulting 2749 * string is truncated. 2750 * 2751 * If you're not already dealing with a va_list consider using snprintf(). 2752 */ vsnprintf(char * buf,size_t size,const char * fmt,va_list args)2753 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2754 { 2755 unsigned long long num; 2756 char *str, *end; 2757 struct printf_spec spec = {0}; 2758 2759 /* Reject out-of-range values early. Large positive sizes are 2760 used for unknown buffer sizes. */ 2761 if (WARN_ON_ONCE(size > INT_MAX)) 2762 return 0; 2763 2764 str = buf; 2765 end = buf + size; 2766 2767 /* Make sure end is always >= buf */ 2768 if (end < buf) { 2769 end = ((void *)-1); 2770 size = end - buf; 2771 } 2772 2773 while (*fmt) { 2774 const char *old_fmt = fmt; 2775 int read = format_decode(fmt, &spec); 2776 2777 fmt += read; 2778 2779 switch (spec.type) { 2780 case FORMAT_TYPE_NONE: { 2781 int copy = read; 2782 if (str < end) { 2783 if (copy > end - str) 2784 copy = end - str; 2785 memcpy(str, old_fmt, copy); 2786 } 2787 str += read; 2788 break; 2789 } 2790 2791 case FORMAT_TYPE_WIDTH: 2792 set_field_width(&spec, va_arg(args, int)); 2793 break; 2794 2795 case FORMAT_TYPE_PRECISION: 2796 set_precision(&spec, va_arg(args, int)); 2797 break; 2798 2799 case FORMAT_TYPE_CHAR: { 2800 char c; 2801 2802 if (!(spec.flags & LEFT)) { 2803 while (--spec.field_width > 0) { 2804 if (str < end) 2805 *str = ' '; 2806 ++str; 2807 2808 } 2809 } 2810 c = (unsigned char) va_arg(args, int); 2811 if (str < end) 2812 *str = c; 2813 ++str; 2814 while (--spec.field_width > 0) { 2815 if (str < end) 2816 *str = ' '; 2817 ++str; 2818 } 2819 break; 2820 } 2821 2822 case FORMAT_TYPE_STR: 2823 str = string(str, end, va_arg(args, char *), spec); 2824 break; 2825 2826 case FORMAT_TYPE_PTR: 2827 str = pointer(fmt, str, end, va_arg(args, void *), 2828 spec); 2829 while (isalnum(*fmt)) 2830 fmt++; 2831 break; 2832 2833 case FORMAT_TYPE_PERCENT_CHAR: 2834 if (str < end) 2835 *str = '%'; 2836 ++str; 2837 break; 2838 2839 case FORMAT_TYPE_INVALID: 2840 /* 2841 * Presumably the arguments passed gcc's type 2842 * checking, but there is no safe or sane way 2843 * for us to continue parsing the format and 2844 * fetching from the va_list; the remaining 2845 * specifiers and arguments would be out of 2846 * sync. 2847 */ 2848 goto out; 2849 2850 default: 2851 switch (spec.type) { 2852 case FORMAT_TYPE_LONG_LONG: 2853 num = va_arg(args, long long); 2854 break; 2855 case FORMAT_TYPE_ULONG: 2856 num = va_arg(args, unsigned long); 2857 break; 2858 case FORMAT_TYPE_LONG: 2859 num = va_arg(args, long); 2860 break; 2861 case FORMAT_TYPE_SIZE_T: 2862 if (spec.flags & SIGN) 2863 num = va_arg(args, ssize_t); 2864 else 2865 num = va_arg(args, size_t); 2866 break; 2867 case FORMAT_TYPE_PTRDIFF: 2868 num = va_arg(args, ptrdiff_t); 2869 break; 2870 case FORMAT_TYPE_UBYTE: 2871 num = (unsigned char) va_arg(args, int); 2872 break; 2873 case FORMAT_TYPE_BYTE: 2874 num = (signed char) va_arg(args, int); 2875 break; 2876 case FORMAT_TYPE_USHORT: 2877 num = (unsigned short) va_arg(args, int); 2878 break; 2879 case FORMAT_TYPE_SHORT: 2880 num = (short) va_arg(args, int); 2881 break; 2882 case FORMAT_TYPE_INT: 2883 num = (int) va_arg(args, int); 2884 break; 2885 default: 2886 num = va_arg(args, unsigned int); 2887 } 2888 2889 str = number(str, end, num, spec); 2890 } 2891 } 2892 2893 out: 2894 if (size > 0) { 2895 if (str < end) 2896 *str = '\0'; 2897 else 2898 end[-1] = '\0'; 2899 } 2900 2901 /* the trailing null byte doesn't count towards the total */ 2902 return str-buf; 2903 2904 } 2905 EXPORT_SYMBOL(vsnprintf); 2906 2907 /** 2908 * vscnprintf - Format a string and place it in a buffer 2909 * @buf: The buffer to place the result into 2910 * @size: The size of the buffer, including the trailing null space 2911 * @fmt: The format string to use 2912 * @args: Arguments for the format string 2913 * 2914 * The return value is the number of characters which have been written into 2915 * the @buf not including the trailing '\0'. If @size is == 0 the function 2916 * returns 0. 2917 * 2918 * If you're not already dealing with a va_list consider using scnprintf(). 2919 * 2920 * See the vsnprintf() documentation for format string extensions over C99. 2921 */ vscnprintf(char * buf,size_t size,const char * fmt,va_list args)2922 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2923 { 2924 int i; 2925 2926 if (unlikely(!size)) 2927 return 0; 2928 2929 i = vsnprintf(buf, size, fmt, args); 2930 2931 if (likely(i < size)) 2932 return i; 2933 2934 return size - 1; 2935 } 2936 EXPORT_SYMBOL(vscnprintf); 2937 2938 /** 2939 * snprintf - Format a string and place it in a buffer 2940 * @buf: The buffer to place the result into 2941 * @size: The size of the buffer, including the trailing null space 2942 * @fmt: The format string to use 2943 * @...: Arguments for the format string 2944 * 2945 * The return value is the number of characters which would be 2946 * generated for the given input, excluding the trailing null, 2947 * as per ISO C99. If the return is greater than or equal to 2948 * @size, the resulting string is truncated. 2949 * 2950 * See the vsnprintf() documentation for format string extensions over C99. 2951 */ snprintf(char * buf,size_t size,const char * fmt,...)2952 int snprintf(char *buf, size_t size, const char *fmt, ...) 2953 { 2954 va_list args; 2955 int i; 2956 2957 va_start(args, fmt); 2958 i = vsnprintf(buf, size, fmt, args); 2959 va_end(args); 2960 2961 return i; 2962 } 2963 EXPORT_SYMBOL(snprintf); 2964 2965 /** 2966 * scnprintf - Format a string and place it in a buffer 2967 * @buf: The buffer to place the result into 2968 * @size: The size of the buffer, including the trailing null space 2969 * @fmt: The format string to use 2970 * @...: Arguments for the format string 2971 * 2972 * The return value is the number of characters written into @buf not including 2973 * the trailing '\0'. If @size is == 0 the function returns 0. 2974 */ 2975 scnprintf(char * buf,size_t size,const char * fmt,...)2976 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2977 { 2978 va_list args; 2979 int i; 2980 2981 va_start(args, fmt); 2982 i = vscnprintf(buf, size, fmt, args); 2983 va_end(args); 2984 2985 return i; 2986 } 2987 EXPORT_SYMBOL(scnprintf); 2988 2989 /** 2990 * vsprintf - Format a string and place it in a buffer 2991 * @buf: The buffer to place the result into 2992 * @fmt: The format string to use 2993 * @args: Arguments for the format string 2994 * 2995 * The function returns the number of characters written 2996 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2997 * buffer overflows. 2998 * 2999 * If you're not already dealing with a va_list consider using sprintf(). 3000 * 3001 * See the vsnprintf() documentation for format string extensions over C99. 3002 */ vsprintf(char * buf,const char * fmt,va_list args)3003 int vsprintf(char *buf, const char *fmt, va_list args) 3004 { 3005 return vsnprintf(buf, INT_MAX, fmt, args); 3006 } 3007 EXPORT_SYMBOL(vsprintf); 3008 3009 /** 3010 * sprintf - Format a string and place it in a buffer 3011 * @buf: The buffer to place the result into 3012 * @fmt: The format string to use 3013 * @...: Arguments for the format string 3014 * 3015 * The function returns the number of characters written 3016 * into @buf. Use snprintf() or scnprintf() in order to avoid 3017 * buffer overflows. 3018 * 3019 * See the vsnprintf() documentation for format string extensions over C99. 3020 */ sprintf(char * buf,const char * fmt,...)3021 int sprintf(char *buf, const char *fmt, ...) 3022 { 3023 va_list args; 3024 int i; 3025 3026 va_start(args, fmt); 3027 i = vsnprintf(buf, INT_MAX, fmt, args); 3028 va_end(args); 3029 3030 return i; 3031 } 3032 EXPORT_SYMBOL(sprintf); 3033 3034 #ifdef CONFIG_BINARY_PRINTF 3035 /* 3036 * bprintf service: 3037 * vbin_printf() - VA arguments to binary data 3038 * bstr_printf() - Binary data to text string 3039 */ 3040 3041 /** 3042 * vbin_printf - Parse a format string and place args' binary value in a buffer 3043 * @bin_buf: The buffer to place args' binary value 3044 * @size: The size of the buffer(by words(32bits), not characters) 3045 * @fmt: The format string to use 3046 * @args: Arguments for the format string 3047 * 3048 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3049 * is skipped. 3050 * 3051 * The return value is the number of words(32bits) which would be generated for 3052 * the given input. 3053 * 3054 * NOTE: 3055 * If the return value is greater than @size, the resulting bin_buf is NOT 3056 * valid for bstr_printf(). 3057 */ vbin_printf(u32 * bin_buf,size_t size,const char * fmt,va_list args)3058 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 3059 { 3060 struct printf_spec spec = {0}; 3061 char *str, *end; 3062 int width; 3063 3064 str = (char *)bin_buf; 3065 end = (char *)(bin_buf + size); 3066 3067 #define save_arg(type) \ 3068 ({ \ 3069 unsigned long long value; \ 3070 if (sizeof(type) == 8) { \ 3071 unsigned long long val8; \ 3072 str = PTR_ALIGN(str, sizeof(u32)); \ 3073 val8 = va_arg(args, unsigned long long); \ 3074 if (str + sizeof(type) <= end) { \ 3075 *(u32 *)str = *(u32 *)&val8; \ 3076 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3077 } \ 3078 value = val8; \ 3079 } else { \ 3080 unsigned int val4; \ 3081 str = PTR_ALIGN(str, sizeof(type)); \ 3082 val4 = va_arg(args, int); \ 3083 if (str + sizeof(type) <= end) \ 3084 *(typeof(type) *)str = (type)(long)val4; \ 3085 value = (unsigned long long)val4; \ 3086 } \ 3087 str += sizeof(type); \ 3088 value; \ 3089 }) 3090 3091 while (*fmt) { 3092 int read = format_decode(fmt, &spec); 3093 3094 fmt += read; 3095 3096 switch (spec.type) { 3097 case FORMAT_TYPE_NONE: 3098 case FORMAT_TYPE_PERCENT_CHAR: 3099 break; 3100 case FORMAT_TYPE_INVALID: 3101 goto out; 3102 3103 case FORMAT_TYPE_WIDTH: 3104 case FORMAT_TYPE_PRECISION: 3105 width = (int)save_arg(int); 3106 /* Pointers may require the width */ 3107 if (*fmt == 'p') 3108 set_field_width(&spec, width); 3109 break; 3110 3111 case FORMAT_TYPE_CHAR: 3112 save_arg(char); 3113 break; 3114 3115 case FORMAT_TYPE_STR: { 3116 const char *save_str = va_arg(args, char *); 3117 const char *err_msg; 3118 size_t len; 3119 3120 err_msg = check_pointer_msg(save_str); 3121 if (err_msg) 3122 save_str = err_msg; 3123 3124 len = strlen(save_str) + 1; 3125 if (str + len < end) 3126 memcpy(str, save_str, len); 3127 str += len; 3128 break; 3129 } 3130 3131 case FORMAT_TYPE_PTR: 3132 /* Dereferenced pointers must be done now */ 3133 switch (*fmt) { 3134 /* Dereference of functions is still OK */ 3135 case 'S': 3136 case 's': 3137 case 'x': 3138 case 'K': 3139 case 'e': 3140 save_arg(void *); 3141 break; 3142 default: 3143 if (!isalnum(*fmt)) { 3144 save_arg(void *); 3145 break; 3146 } 3147 str = pointer(fmt, str, end, va_arg(args, void *), 3148 spec); 3149 if (str + 1 < end) 3150 *str++ = '\0'; 3151 else 3152 end[-1] = '\0'; /* Must be nul terminated */ 3153 } 3154 /* skip all alphanumeric pointer suffixes */ 3155 while (isalnum(*fmt)) 3156 fmt++; 3157 break; 3158 3159 default: 3160 switch (spec.type) { 3161 3162 case FORMAT_TYPE_LONG_LONG: 3163 save_arg(long long); 3164 break; 3165 case FORMAT_TYPE_ULONG: 3166 case FORMAT_TYPE_LONG: 3167 save_arg(unsigned long); 3168 break; 3169 case FORMAT_TYPE_SIZE_T: 3170 save_arg(size_t); 3171 break; 3172 case FORMAT_TYPE_PTRDIFF: 3173 save_arg(ptrdiff_t); 3174 break; 3175 case FORMAT_TYPE_UBYTE: 3176 case FORMAT_TYPE_BYTE: 3177 save_arg(char); 3178 break; 3179 case FORMAT_TYPE_USHORT: 3180 case FORMAT_TYPE_SHORT: 3181 save_arg(short); 3182 break; 3183 default: 3184 save_arg(int); 3185 } 3186 } 3187 } 3188 3189 out: 3190 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3191 #undef save_arg 3192 } 3193 EXPORT_SYMBOL_GPL(vbin_printf); 3194 3195 /** 3196 * bstr_printf - Format a string from binary arguments and place it in a buffer 3197 * @buf: The buffer to place the result into 3198 * @size: The size of the buffer, including the trailing null space 3199 * @fmt: The format string to use 3200 * @bin_buf: Binary arguments for the format string 3201 * 3202 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3203 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3204 * a binary buffer that generated by vbin_printf. 3205 * 3206 * The format follows C99 vsnprintf, but has some extensions: 3207 * see vsnprintf comment for details. 3208 * 3209 * The return value is the number of characters which would 3210 * be generated for the given input, excluding the trailing 3211 * '\0', as per ISO C99. If you want to have the exact 3212 * number of characters written into @buf as return value 3213 * (not including the trailing '\0'), use vscnprintf(). If the 3214 * return is greater than or equal to @size, the resulting 3215 * string is truncated. 3216 */ bstr_printf(char * buf,size_t size,const char * fmt,const u32 * bin_buf)3217 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 3218 { 3219 struct printf_spec spec = {0}; 3220 char *str, *end; 3221 const char *args = (const char *)bin_buf; 3222 3223 if (WARN_ON_ONCE(size > INT_MAX)) 3224 return 0; 3225 3226 str = buf; 3227 end = buf + size; 3228 3229 #define get_arg(type) \ 3230 ({ \ 3231 typeof(type) value; \ 3232 if (sizeof(type) == 8) { \ 3233 args = PTR_ALIGN(args, sizeof(u32)); \ 3234 *(u32 *)&value = *(u32 *)args; \ 3235 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3236 } else { \ 3237 args = PTR_ALIGN(args, sizeof(type)); \ 3238 value = *(typeof(type) *)args; \ 3239 } \ 3240 args += sizeof(type); \ 3241 value; \ 3242 }) 3243 3244 /* Make sure end is always >= buf */ 3245 if (end < buf) { 3246 end = ((void *)-1); 3247 size = end - buf; 3248 } 3249 3250 while (*fmt) { 3251 const char *old_fmt = fmt; 3252 int read = format_decode(fmt, &spec); 3253 3254 fmt += read; 3255 3256 switch (spec.type) { 3257 case FORMAT_TYPE_NONE: { 3258 int copy = read; 3259 if (str < end) { 3260 if (copy > end - str) 3261 copy = end - str; 3262 memcpy(str, old_fmt, copy); 3263 } 3264 str += read; 3265 break; 3266 } 3267 3268 case FORMAT_TYPE_WIDTH: 3269 set_field_width(&spec, get_arg(int)); 3270 break; 3271 3272 case FORMAT_TYPE_PRECISION: 3273 set_precision(&spec, get_arg(int)); 3274 break; 3275 3276 case FORMAT_TYPE_CHAR: { 3277 char c; 3278 3279 if (!(spec.flags & LEFT)) { 3280 while (--spec.field_width > 0) { 3281 if (str < end) 3282 *str = ' '; 3283 ++str; 3284 } 3285 } 3286 c = (unsigned char) get_arg(char); 3287 if (str < end) 3288 *str = c; 3289 ++str; 3290 while (--spec.field_width > 0) { 3291 if (str < end) 3292 *str = ' '; 3293 ++str; 3294 } 3295 break; 3296 } 3297 3298 case FORMAT_TYPE_STR: { 3299 const char *str_arg = args; 3300 args += strlen(str_arg) + 1; 3301 str = string(str, end, (char *)str_arg, spec); 3302 break; 3303 } 3304 3305 case FORMAT_TYPE_PTR: { 3306 bool process = false; 3307 int copy, len; 3308 /* Non function dereferences were already done */ 3309 switch (*fmt) { 3310 case 'S': 3311 case 's': 3312 case 'x': 3313 case 'K': 3314 case 'e': 3315 process = true; 3316 break; 3317 default: 3318 if (!isalnum(*fmt)) { 3319 process = true; 3320 break; 3321 } 3322 /* Pointer dereference was already processed */ 3323 if (str < end) { 3324 len = copy = strlen(args); 3325 if (copy > end - str) 3326 copy = end - str; 3327 memcpy(str, args, copy); 3328 str += len; 3329 args += len + 1; 3330 } 3331 } 3332 if (process) 3333 str = pointer(fmt, str, end, get_arg(void *), spec); 3334 3335 while (isalnum(*fmt)) 3336 fmt++; 3337 break; 3338 } 3339 3340 case FORMAT_TYPE_PERCENT_CHAR: 3341 if (str < end) 3342 *str = '%'; 3343 ++str; 3344 break; 3345 3346 case FORMAT_TYPE_INVALID: 3347 goto out; 3348 3349 default: { 3350 unsigned long long num; 3351 3352 switch (spec.type) { 3353 3354 case FORMAT_TYPE_LONG_LONG: 3355 num = get_arg(long long); 3356 break; 3357 case FORMAT_TYPE_ULONG: 3358 case FORMAT_TYPE_LONG: 3359 num = get_arg(unsigned long); 3360 break; 3361 case FORMAT_TYPE_SIZE_T: 3362 num = get_arg(size_t); 3363 break; 3364 case FORMAT_TYPE_PTRDIFF: 3365 num = get_arg(ptrdiff_t); 3366 break; 3367 case FORMAT_TYPE_UBYTE: 3368 num = get_arg(unsigned char); 3369 break; 3370 case FORMAT_TYPE_BYTE: 3371 num = get_arg(signed char); 3372 break; 3373 case FORMAT_TYPE_USHORT: 3374 num = get_arg(unsigned short); 3375 break; 3376 case FORMAT_TYPE_SHORT: 3377 num = get_arg(short); 3378 break; 3379 case FORMAT_TYPE_UINT: 3380 num = get_arg(unsigned int); 3381 break; 3382 default: 3383 num = get_arg(int); 3384 } 3385 3386 str = number(str, end, num, spec); 3387 } /* default: */ 3388 } /* switch(spec.type) */ 3389 } /* while(*fmt) */ 3390 3391 out: 3392 if (size > 0) { 3393 if (str < end) 3394 *str = '\0'; 3395 else 3396 end[-1] = '\0'; 3397 } 3398 3399 #undef get_arg 3400 3401 /* the trailing null byte doesn't count towards the total */ 3402 return str - buf; 3403 } 3404 EXPORT_SYMBOL_GPL(bstr_printf); 3405 3406 /** 3407 * bprintf - Parse a format string and place args' binary value in a buffer 3408 * @bin_buf: The buffer to place args' binary value 3409 * @size: The size of the buffer(by words(32bits), not characters) 3410 * @fmt: The format string to use 3411 * @...: Arguments for the format string 3412 * 3413 * The function returns the number of words(u32) written 3414 * into @bin_buf. 3415 */ bprintf(u32 * bin_buf,size_t size,const char * fmt,...)3416 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 3417 { 3418 va_list args; 3419 int ret; 3420 3421 va_start(args, fmt); 3422 ret = vbin_printf(bin_buf, size, fmt, args); 3423 va_end(args); 3424 3425 return ret; 3426 } 3427 EXPORT_SYMBOL_GPL(bprintf); 3428 3429 #endif /* CONFIG_BINARY_PRINTF */ 3430 3431 /** 3432 * vsscanf - Unformat a buffer into a list of arguments 3433 * @buf: input buffer 3434 * @fmt: format of buffer 3435 * @args: arguments 3436 */ vsscanf(const char * buf,const char * fmt,va_list args)3437 int vsscanf(const char *buf, const char *fmt, va_list args) 3438 { 3439 const char *str = buf; 3440 char *next; 3441 char digit; 3442 int num = 0; 3443 u8 qualifier; 3444 unsigned int base; 3445 union { 3446 long long s; 3447 unsigned long long u; 3448 } val; 3449 s16 field_width; 3450 bool is_sign; 3451 3452 while (*fmt) { 3453 /* skip any white space in format */ 3454 /* white space in format matches any amount of 3455 * white space, including none, in the input. 3456 */ 3457 if (isspace(*fmt)) { 3458 fmt = skip_spaces(++fmt); 3459 str = skip_spaces(str); 3460 } 3461 3462 /* anything that is not a conversion must match exactly */ 3463 if (*fmt != '%' && *fmt) { 3464 if (*fmt++ != *str++) 3465 break; 3466 continue; 3467 } 3468 3469 if (!*fmt) 3470 break; 3471 ++fmt; 3472 3473 /* skip this conversion. 3474 * advance both strings to next white space 3475 */ 3476 if (*fmt == '*') { 3477 if (!*str) 3478 break; 3479 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3480 /* '%*[' not yet supported, invalid format */ 3481 if (*fmt == '[') 3482 return num; 3483 fmt++; 3484 } 3485 while (!isspace(*str) && *str) 3486 str++; 3487 continue; 3488 } 3489 3490 /* get field width */ 3491 field_width = -1; 3492 if (isdigit(*fmt)) { 3493 field_width = skip_atoi(&fmt); 3494 if (field_width <= 0) 3495 break; 3496 } 3497 3498 /* get conversion qualifier */ 3499 qualifier = -1; 3500 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3501 *fmt == 'z') { 3502 qualifier = *fmt++; 3503 if (unlikely(qualifier == *fmt)) { 3504 if (qualifier == 'h') { 3505 qualifier = 'H'; 3506 fmt++; 3507 } else if (qualifier == 'l') { 3508 qualifier = 'L'; 3509 fmt++; 3510 } 3511 } 3512 } 3513 3514 if (!*fmt) 3515 break; 3516 3517 if (*fmt == 'n') { 3518 /* return number of characters read so far */ 3519 *va_arg(args, int *) = str - buf; 3520 ++fmt; 3521 continue; 3522 } 3523 3524 if (!*str) 3525 break; 3526 3527 base = 10; 3528 is_sign = false; 3529 3530 switch (*fmt++) { 3531 case 'c': 3532 { 3533 char *s = (char *)va_arg(args, char*); 3534 if (field_width == -1) 3535 field_width = 1; 3536 do { 3537 *s++ = *str++; 3538 } while (--field_width > 0 && *str); 3539 num++; 3540 } 3541 continue; 3542 case 's': 3543 { 3544 char *s = (char *)va_arg(args, char *); 3545 if (field_width == -1) 3546 field_width = SHRT_MAX; 3547 /* first, skip leading white space in buffer */ 3548 str = skip_spaces(str); 3549 3550 /* now copy until next white space */ 3551 while (*str && !isspace(*str) && field_width--) 3552 *s++ = *str++; 3553 *s = '\0'; 3554 num++; 3555 } 3556 continue; 3557 /* 3558 * Warning: This implementation of the '[' conversion specifier 3559 * deviates from its glibc counterpart in the following ways: 3560 * (1) It does NOT support ranges i.e. '-' is NOT a special 3561 * character 3562 * (2) It cannot match the closing bracket ']' itself 3563 * (3) A field width is required 3564 * (4) '%*[' (discard matching input) is currently not supported 3565 * 3566 * Example usage: 3567 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3568 * buf1, buf2, buf3); 3569 * if (ret < 3) 3570 * // etc.. 3571 */ 3572 case '[': 3573 { 3574 char *s = (char *)va_arg(args, char *); 3575 DECLARE_BITMAP(set, 256) = {0}; 3576 unsigned int len = 0; 3577 bool negate = (*fmt == '^'); 3578 3579 /* field width is required */ 3580 if (field_width == -1) 3581 return num; 3582 3583 if (negate) 3584 ++fmt; 3585 3586 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3587 __set_bit((u8)*fmt, set); 3588 3589 /* no ']' or no character set found */ 3590 if (!*fmt || !len) 3591 return num; 3592 ++fmt; 3593 3594 if (negate) { 3595 bitmap_complement(set, set, 256); 3596 /* exclude null '\0' byte */ 3597 __clear_bit(0, set); 3598 } 3599 3600 /* match must be non-empty */ 3601 if (!test_bit((u8)*str, set)) 3602 return num; 3603 3604 while (test_bit((u8)*str, set) && field_width--) 3605 *s++ = *str++; 3606 *s = '\0'; 3607 ++num; 3608 } 3609 continue; 3610 case 'o': 3611 base = 8; 3612 break; 3613 case 'x': 3614 case 'X': 3615 base = 16; 3616 break; 3617 case 'i': 3618 base = 0; 3619 fallthrough; 3620 case 'd': 3621 is_sign = true; 3622 fallthrough; 3623 case 'u': 3624 break; 3625 case '%': 3626 /* looking for '%' in str */ 3627 if (*str++ != '%') 3628 return num; 3629 continue; 3630 default: 3631 /* invalid format; stop here */ 3632 return num; 3633 } 3634 3635 /* have some sort of integer conversion. 3636 * first, skip white space in buffer. 3637 */ 3638 str = skip_spaces(str); 3639 3640 digit = *str; 3641 if (is_sign && digit == '-') { 3642 if (field_width == 1) 3643 break; 3644 3645 digit = *(str + 1); 3646 } 3647 3648 if (!digit 3649 || (base == 16 && !isxdigit(digit)) 3650 || (base == 10 && !isdigit(digit)) 3651 || (base == 8 && !isodigit(digit)) 3652 || (base == 0 && !isdigit(digit))) 3653 break; 3654 3655 if (is_sign) 3656 val.s = simple_strntoll(str, 3657 field_width >= 0 ? field_width : INT_MAX, 3658 &next, base); 3659 else 3660 val.u = simple_strntoull(str, 3661 field_width >= 0 ? field_width : INT_MAX, 3662 &next, base); 3663 3664 switch (qualifier) { 3665 case 'H': /* that's 'hh' in format */ 3666 if (is_sign) 3667 *va_arg(args, signed char *) = val.s; 3668 else 3669 *va_arg(args, unsigned char *) = val.u; 3670 break; 3671 case 'h': 3672 if (is_sign) 3673 *va_arg(args, short *) = val.s; 3674 else 3675 *va_arg(args, unsigned short *) = val.u; 3676 break; 3677 case 'l': 3678 if (is_sign) 3679 *va_arg(args, long *) = val.s; 3680 else 3681 *va_arg(args, unsigned long *) = val.u; 3682 break; 3683 case 'L': 3684 if (is_sign) 3685 *va_arg(args, long long *) = val.s; 3686 else 3687 *va_arg(args, unsigned long long *) = val.u; 3688 break; 3689 case 'z': 3690 *va_arg(args, size_t *) = val.u; 3691 break; 3692 default: 3693 if (is_sign) 3694 *va_arg(args, int *) = val.s; 3695 else 3696 *va_arg(args, unsigned int *) = val.u; 3697 break; 3698 } 3699 num++; 3700 3701 if (!next) 3702 break; 3703 str = next; 3704 } 3705 3706 return num; 3707 } 3708 EXPORT_SYMBOL(vsscanf); 3709 3710 /** 3711 * sscanf - Unformat a buffer into a list of arguments 3712 * @buf: input buffer 3713 * @fmt: formatting of buffer 3714 * @...: resulting arguments 3715 */ sscanf(const char * buf,const char * fmt,...)3716 int sscanf(const char *buf, const char *fmt, ...) 3717 { 3718 va_list args; 3719 int i; 3720 3721 va_start(args, fmt); 3722 i = vsscanf(buf, fmt, args); 3723 va_end(args); 3724 3725 return i; 3726 } 3727 EXPORT_SYMBOL(sscanf); 3728