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 <linux/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 63 noinline 64 static unsigned long long simple_strntoull(const char *startp, char **endp, unsigned int base, size_t max_chars) 65 { 66 const char *cp; 67 unsigned long long result = 0ULL; 68 size_t prefix_chars; 69 unsigned int rv; 70 71 cp = _parse_integer_fixup_radix(startp, &base); 72 prefix_chars = cp - startp; 73 if (prefix_chars < max_chars) { 74 rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); 75 /* FIXME */ 76 cp += (rv & ~KSTRTOX_OVERFLOW); 77 } else { 78 /* Field too short for prefix + digit, skip over without converting */ 79 cp = startp + max_chars; 80 } 81 82 if (endp) 83 *endp = (char *)cp; 84 85 return result; 86 } 87 88 /** 89 * simple_strtoull - convert a string to an unsigned long long 90 * @cp: The start of the string 91 * @endp: A pointer to the end of the parsed string will be placed here 92 * @base: The number base to use 93 * 94 * This function has caveats. Please use kstrtoull instead. 95 */ 96 noinline 97 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 98 { 99 return simple_strntoull(cp, endp, base, INT_MAX); 100 } 101 EXPORT_SYMBOL(simple_strtoull); 102 103 /** 104 * simple_strtoul - convert a string to an unsigned long 105 * @cp: The start of the string 106 * @endp: A pointer to the end of the parsed string will be placed here 107 * @base: The number base to use 108 * 109 * This function has caveats. Please use kstrtoul instead. 110 */ 111 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 112 { 113 return simple_strtoull(cp, endp, base); 114 } 115 EXPORT_SYMBOL(simple_strtoul); 116 117 unsigned long simple_strntoul(const char *cp, char **endp, unsigned int base, 118 size_t max_chars) 119 { 120 return simple_strntoull(cp, endp, base, max_chars); 121 } 122 EXPORT_SYMBOL(simple_strntoul); 123 124 /** 125 * simple_strtol - convert a string to a signed long 126 * @cp: The start of the string 127 * @endp: A pointer to the end of the parsed string will be placed here 128 * @base: The number base to use 129 * 130 * This function has caveats. Please use kstrtol instead. 131 */ 132 long simple_strtol(const char *cp, char **endp, unsigned int base) 133 { 134 if (*cp == '-') 135 return -simple_strtoul(cp + 1, endp, base); 136 137 return simple_strtoul(cp, endp, base); 138 } 139 EXPORT_SYMBOL(simple_strtol); 140 141 noinline 142 static long long simple_strntoll(const char *cp, char **endp, unsigned int base, size_t max_chars) 143 { 144 /* 145 * simple_strntoull() safely handles receiving max_chars==0 in the 146 * case cp[0] == '-' && max_chars == 1. 147 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 148 * and the content of *cp is irrelevant. 149 */ 150 if (*cp == '-' && max_chars > 0) 151 return -simple_strntoull(cp + 1, endp, base, max_chars - 1); 152 153 return simple_strntoull(cp, endp, base, max_chars); 154 } 155 156 /** 157 * simple_strtoll - convert a string to a signed long long 158 * @cp: The start of the string 159 * @endp: A pointer to the end of the parsed string will be placed here 160 * @base: The number base to use 161 * 162 * This function has caveats. Please use kstrtoll instead. 163 */ 164 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 165 { 166 return simple_strntoll(cp, endp, base, INT_MAX); 167 } 168 EXPORT_SYMBOL(simple_strtoll); 169 170 static inline int skip_atoi(const char **s) 171 { 172 int i = 0; 173 174 do { 175 i = i*10 + *((*s)++) - '0'; 176 } while (isdigit(**s)); 177 178 return i; 179 } 180 181 /* 182 * Decimal conversion is by far the most typical, and is used for 183 * /proc and /sys data. This directly impacts e.g. top performance 184 * with many processes running. We optimize it for speed by emitting 185 * two characters at a time, using a 200 byte lookup table. This 186 * roughly halves the number of multiplications compared to computing 187 * the digits one at a time. Implementation strongly inspired by the 188 * previous version, which in turn used ideas described at 189 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 190 * from the author, Douglas W. Jones). 191 * 192 * It turns out there is precisely one 26 bit fixed-point 193 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 194 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 195 * range happens to be somewhat larger (x <= 1073741898), but that's 196 * irrelevant for our purpose. 197 * 198 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 199 * need a 32x32->64 bit multiply, so we simply use the same constant. 200 * 201 * For dividing a number in the range [100, 10^4-1] by 100, there are 202 * several options. The simplest is (x * 0x147b) >> 19, which is valid 203 * for all x <= 43698. 204 */ 205 206 static const u16 decpair[100] = { 207 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 208 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 209 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 210 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 211 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 212 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 213 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 214 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 215 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 216 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 217 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 218 #undef _ 219 }; 220 221 /* 222 * This will print a single '0' even if r == 0, since we would 223 * immediately jump to out_r where two 0s would be written but only 224 * one of them accounted for in buf. This is needed by ip4_string 225 * below. All other callers pass a non-zero value of r. 226 */ 227 static noinline_for_stack 228 char *put_dec_trunc8(char *buf, unsigned r) 229 { 230 unsigned q; 231 232 /* 1 <= r < 10^8 */ 233 if (r < 100) 234 goto out_r; 235 236 /* 100 <= r < 10^8 */ 237 q = (r * (u64)0x28f5c29) >> 32; 238 *((u16 *)buf) = decpair[r - 100*q]; 239 buf += 2; 240 241 /* 1 <= q < 10^6 */ 242 if (q < 100) 243 goto out_q; 244 245 /* 100 <= q < 10^6 */ 246 r = (q * (u64)0x28f5c29) >> 32; 247 *((u16 *)buf) = decpair[q - 100*r]; 248 buf += 2; 249 250 /* 1 <= r < 10^4 */ 251 if (r < 100) 252 goto out_r; 253 254 /* 100 <= r < 10^4 */ 255 q = (r * 0x147b) >> 19; 256 *((u16 *)buf) = decpair[r - 100*q]; 257 buf += 2; 258 out_q: 259 /* 1 <= q < 100 */ 260 r = q; 261 out_r: 262 /* 1 <= r < 100 */ 263 *((u16 *)buf) = decpair[r]; 264 buf += r < 10 ? 1 : 2; 265 return buf; 266 } 267 268 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 269 static noinline_for_stack 270 char *put_dec_full8(char *buf, unsigned r) 271 { 272 unsigned q; 273 274 /* 0 <= r < 10^8 */ 275 q = (r * (u64)0x28f5c29) >> 32; 276 *((u16 *)buf) = decpair[r - 100*q]; 277 buf += 2; 278 279 /* 0 <= q < 10^6 */ 280 r = (q * (u64)0x28f5c29) >> 32; 281 *((u16 *)buf) = decpair[q - 100*r]; 282 buf += 2; 283 284 /* 0 <= r < 10^4 */ 285 q = (r * 0x147b) >> 19; 286 *((u16 *)buf) = decpair[r - 100*q]; 287 buf += 2; 288 289 /* 0 <= q < 100 */ 290 *((u16 *)buf) = decpair[q]; 291 buf += 2; 292 return buf; 293 } 294 295 static noinline_for_stack 296 char *put_dec(char *buf, unsigned long long n) 297 { 298 if (n >= 100*1000*1000) 299 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 300 /* 1 <= n <= 1.6e11 */ 301 if (n >= 100*1000*1000) 302 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 303 /* 1 <= n < 1e8 */ 304 return put_dec_trunc8(buf, n); 305 } 306 307 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 308 309 static void 310 put_dec_full4(char *buf, unsigned r) 311 { 312 unsigned q; 313 314 /* 0 <= r < 10^4 */ 315 q = (r * 0x147b) >> 19; 316 *((u16 *)buf) = decpair[r - 100*q]; 317 buf += 2; 318 /* 0 <= q < 100 */ 319 *((u16 *)buf) = decpair[q]; 320 } 321 322 /* 323 * Call put_dec_full4 on x % 10000, return x / 10000. 324 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 325 * holds for all x < 1,128,869,999. The largest value this 326 * helper will ever be asked to convert is 1,125,520,955. 327 * (second call in the put_dec code, assuming n is all-ones). 328 */ 329 static noinline_for_stack 330 unsigned put_dec_helper4(char *buf, unsigned x) 331 { 332 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 333 334 put_dec_full4(buf, x - q * 10000); 335 return q; 336 } 337 338 /* Based on code by Douglas W. Jones found at 339 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 340 * (with permission from the author). 341 * Performs no 64-bit division and hence should be fast on 32-bit machines. 342 */ 343 static 344 char *put_dec(char *buf, unsigned long long n) 345 { 346 uint32_t d3, d2, d1, q, h; 347 348 if (n < 100*1000*1000) 349 return put_dec_trunc8(buf, n); 350 351 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 352 h = (n >> 32); 353 d2 = (h ) & 0xffff; 354 d3 = (h >> 16); /* implicit "& 0xffff" */ 355 356 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 357 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 358 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 359 q = put_dec_helper4(buf, q); 360 361 q += 7671 * d3 + 9496 * d2 + 6 * d1; 362 q = put_dec_helper4(buf+4, q); 363 364 q += 4749 * d3 + 42 * d2; 365 q = put_dec_helper4(buf+8, q); 366 367 q += 281 * d3; 368 buf += 12; 369 if (q) 370 buf = put_dec_trunc8(buf, q); 371 else while (buf[-1] == '0') 372 --buf; 373 374 return buf; 375 } 376 377 #endif 378 379 /* 380 * Convert passed number to decimal string. 381 * Returns the length of string. On buffer overflow, returns 0. 382 * 383 * If speed is not important, use snprintf(). It's easy to read the code. 384 */ 385 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 386 { 387 /* put_dec requires 2-byte alignment of the buffer. */ 388 char tmp[sizeof(num) * 3] __aligned(2); 389 int idx, len; 390 391 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 392 if (num <= 9) { 393 tmp[0] = '0' + num; 394 len = 1; 395 } else { 396 len = put_dec(tmp, num) - tmp; 397 } 398 399 if (len > size || width > size) 400 return 0; 401 402 if (width > len) { 403 width = width - len; 404 for (idx = 0; idx < width; idx++) 405 buf[idx] = ' '; 406 } else { 407 width = 0; 408 } 409 410 for (idx = 0; idx < len; ++idx) 411 buf[idx + width] = tmp[len - idx - 1]; 412 413 return len + width; 414 } 415 416 #define SIGN 1 /* unsigned/signed */ 417 #define LEFT 2 /* left justified */ 418 #define PLUS 4 /* show plus */ 419 #define SPACE 8 /* space if plus */ 420 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 421 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 422 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 423 424 static_assert(ZEROPAD == ('0' - ' ')); 425 static_assert(SMALL == ('a' ^ 'A')); 426 427 enum format_state { 428 FORMAT_STATE_NONE, /* Just a string part */ 429 FORMAT_STATE_NUM, 430 FORMAT_STATE_WIDTH, 431 FORMAT_STATE_PRECISION, 432 FORMAT_STATE_CHAR, 433 FORMAT_STATE_STR, 434 FORMAT_STATE_PTR, 435 FORMAT_STATE_PERCENT_CHAR, 436 FORMAT_STATE_INVALID, 437 }; 438 439 struct printf_spec { 440 unsigned char flags; /* flags to number() */ 441 unsigned char base; /* number base, 8, 10 or 16 only */ 442 short precision; /* # of digits/chars */ 443 int field_width; /* width of output field */ 444 } __packed; 445 static_assert(sizeof(struct printf_spec) == 8); 446 447 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 448 #define PRECISION_MAX ((1 << 15) - 1) 449 450 static noinline_for_stack 451 char *number(char *buf, char *end, unsigned long long num, 452 struct printf_spec spec) 453 { 454 /* put_dec requires 2-byte alignment of the buffer. */ 455 char tmp[3 * sizeof(num)] __aligned(2); 456 char sign; 457 char locase; 458 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 459 int i; 460 bool is_zero = num == 0LL; 461 int field_width = spec.field_width; 462 int precision = spec.precision; 463 464 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 465 * produces same digits or (maybe lowercased) letters */ 466 locase = (spec.flags & SMALL); 467 if (spec.flags & LEFT) 468 spec.flags &= ~ZEROPAD; 469 sign = 0; 470 if (spec.flags & SIGN) { 471 if ((signed long long)num < 0) { 472 sign = '-'; 473 num = -(signed long long)num; 474 field_width--; 475 } else if (spec.flags & PLUS) { 476 sign = '+'; 477 field_width--; 478 } else if (spec.flags & SPACE) { 479 sign = ' '; 480 field_width--; 481 } 482 } 483 if (need_pfx) { 484 if (spec.base == 16) 485 field_width -= 2; 486 else if (!is_zero) 487 field_width--; 488 } 489 490 /* generate full string in tmp[], in reverse order */ 491 i = 0; 492 if (num < spec.base) 493 tmp[i++] = hex_asc_upper[num] | locase; 494 else if (spec.base != 10) { /* 8 or 16 */ 495 int mask = spec.base - 1; 496 int shift = 3; 497 498 if (spec.base == 16) 499 shift = 4; 500 do { 501 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 502 num >>= shift; 503 } while (num); 504 } else { /* base 10 */ 505 i = put_dec(tmp, num) - tmp; 506 } 507 508 /* printing 100 using %2d gives "100", not "00" */ 509 if (i > precision) 510 precision = i; 511 /* leading space padding */ 512 field_width -= precision; 513 if (!(spec.flags & (ZEROPAD | LEFT))) { 514 while (--field_width >= 0) { 515 if (buf < end) 516 *buf = ' '; 517 ++buf; 518 } 519 } 520 /* sign */ 521 if (sign) { 522 if (buf < end) 523 *buf = sign; 524 ++buf; 525 } 526 /* "0x" / "0" prefix */ 527 if (need_pfx) { 528 if (spec.base == 16 || !is_zero) { 529 if (buf < end) 530 *buf = '0'; 531 ++buf; 532 } 533 if (spec.base == 16) { 534 if (buf < end) 535 *buf = ('X' | locase); 536 ++buf; 537 } 538 } 539 /* zero or space padding */ 540 if (!(spec.flags & LEFT)) { 541 char c = ' ' + (spec.flags & ZEROPAD); 542 543 while (--field_width >= 0) { 544 if (buf < end) 545 *buf = c; 546 ++buf; 547 } 548 } 549 /* hmm even more zero padding? */ 550 while (i <= --precision) { 551 if (buf < end) 552 *buf = '0'; 553 ++buf; 554 } 555 /* actual digits of result */ 556 while (--i >= 0) { 557 if (buf < end) 558 *buf = tmp[i]; 559 ++buf; 560 } 561 /* trailing space padding */ 562 while (--field_width >= 0) { 563 if (buf < end) 564 *buf = ' '; 565 ++buf; 566 } 567 568 return buf; 569 } 570 571 static noinline_for_stack 572 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 573 { 574 struct printf_spec spec; 575 576 spec.field_width = 2 + 2 * size; /* 0x + hex */ 577 spec.flags = SPECIAL | SMALL | ZEROPAD; 578 spec.base = 16; 579 spec.precision = -1; 580 581 return number(buf, end, num, spec); 582 } 583 584 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 585 { 586 size_t size; 587 if (buf >= end) /* nowhere to put anything */ 588 return; 589 size = end - buf; 590 if (size <= spaces) { 591 memset(buf, ' ', size); 592 return; 593 } 594 if (len) { 595 if (len > size - spaces) 596 len = size - spaces; 597 memmove(buf + spaces, buf, len); 598 } 599 memset(buf, ' ', spaces); 600 } 601 602 /* 603 * Handle field width padding for a string. 604 * @buf: current buffer position 605 * @n: length of string 606 * @end: end of output buffer 607 * @spec: for field width and flags 608 * Returns: new buffer position after padding. 609 */ 610 static noinline_for_stack 611 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 612 { 613 unsigned spaces; 614 615 if (likely(n >= spec.field_width)) 616 return buf; 617 /* we want to pad the sucker */ 618 spaces = spec.field_width - n; 619 if (!(spec.flags & LEFT)) { 620 move_right(buf - n, end, n, spaces); 621 return buf + spaces; 622 } 623 while (spaces--) { 624 if (buf < end) 625 *buf = ' '; 626 ++buf; 627 } 628 return buf; 629 } 630 631 /* Handle string from a well known address. */ 632 static char *string_nocheck(char *buf, char *end, const char *s, 633 struct printf_spec spec) 634 { 635 int len = 0; 636 int lim = spec.precision; 637 638 while (lim--) { 639 char c = *s++; 640 if (!c) 641 break; 642 if (buf < end) 643 *buf = c; 644 ++buf; 645 ++len; 646 } 647 return widen_string(buf, len, end, spec); 648 } 649 650 static char *err_ptr(char *buf, char *end, void *ptr, 651 struct printf_spec spec) 652 { 653 int err = PTR_ERR(ptr); 654 const char *sym = errname(err); 655 656 if (sym) 657 return string_nocheck(buf, end, sym, spec); 658 659 /* 660 * Somebody passed ERR_PTR(-1234) or some other non-existing 661 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 662 * printing it as its decimal representation. 663 */ 664 spec.flags |= SIGN; 665 spec.base = 10; 666 return number(buf, end, err, spec); 667 } 668 669 /* Be careful: error messages must fit into the given buffer. */ 670 static char *error_string(char *buf, char *end, const char *s, 671 struct printf_spec spec) 672 { 673 /* 674 * Hard limit to avoid a completely insane messages. It actually 675 * works pretty well because most error messages are in 676 * the many pointer format modifiers. 677 */ 678 if (spec.precision == -1) 679 spec.precision = 2 * sizeof(void *); 680 681 return string_nocheck(buf, end, s, spec); 682 } 683 684 /* 685 * Do not call any complex external code here. Nested printk()/vsprintf() 686 * might cause infinite loops. Failures might break printk() and would 687 * be hard to debug. 688 */ 689 static const char *check_pointer_msg(const void *ptr) 690 { 691 if (!ptr) 692 return "(null)"; 693 694 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 695 return "(efault)"; 696 697 return NULL; 698 } 699 700 static int check_pointer(char **buf, char *end, const void *ptr, 701 struct printf_spec spec) 702 { 703 const char *err_msg; 704 705 err_msg = check_pointer_msg(ptr); 706 if (err_msg) { 707 *buf = error_string(*buf, end, err_msg, spec); 708 return -EFAULT; 709 } 710 711 return 0; 712 } 713 714 static noinline_for_stack 715 char *string(char *buf, char *end, const char *s, 716 struct printf_spec spec) 717 { 718 if (check_pointer(&buf, end, s, spec)) 719 return buf; 720 721 return string_nocheck(buf, end, s, spec); 722 } 723 724 static char *pointer_string(char *buf, char *end, 725 const void *ptr, 726 struct printf_spec spec) 727 { 728 spec.base = 16; 729 spec.flags |= SMALL; 730 if (spec.field_width == -1) { 731 spec.field_width = 2 * sizeof(ptr); 732 spec.flags |= ZEROPAD; 733 } 734 735 return number(buf, end, (unsigned long int)ptr, spec); 736 } 737 738 /* Make pointers available for printing early in the boot sequence. */ 739 static int debug_boot_weak_hash __ro_after_init; 740 741 static int __init debug_boot_weak_hash_enable(char *str) 742 { 743 debug_boot_weak_hash = 1; 744 pr_info("debug_boot_weak_hash enabled\n"); 745 return 0; 746 } 747 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 748 749 static bool filled_random_ptr_key __read_mostly; 750 static siphash_key_t ptr_key __read_mostly; 751 752 static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) 753 { 754 get_random_bytes(&ptr_key, sizeof(ptr_key)); 755 756 /* Pairs with smp_rmb() before reading ptr_key. */ 757 smp_wmb(); 758 WRITE_ONCE(filled_random_ptr_key, true); 759 return NOTIFY_DONE; 760 } 761 762 static int __init vsprintf_init_hashval(void) 763 { 764 static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; 765 execute_with_initialized_rng(&fill_ptr_key_nb); 766 return 0; 767 } 768 subsys_initcall(vsprintf_init_hashval) 769 770 /* Maps a pointer to a 32 bit unique identifier. */ 771 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 772 { 773 unsigned long hashval; 774 775 if (!READ_ONCE(filled_random_ptr_key)) 776 return -EBUSY; 777 778 /* Pairs with smp_wmb() after writing ptr_key. */ 779 smp_rmb(); 780 781 #ifdef CONFIG_64BIT 782 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 783 /* 784 * Mask off the first 32 bits, this makes explicit that we have 785 * modified the address (and 32 bits is plenty for a unique ID). 786 */ 787 hashval = hashval & 0xffffffff; 788 #else 789 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 790 #endif 791 *hashval_out = hashval; 792 return 0; 793 } 794 795 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 796 { 797 return __ptr_to_hashval(ptr, hashval_out); 798 } 799 800 static char *ptr_to_id(char *buf, char *end, const void *ptr, 801 struct printf_spec spec) 802 { 803 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 804 unsigned long hashval; 805 int ret; 806 807 /* 808 * Print the real pointer value for NULL and error pointers, 809 * as they are not actual addresses. 810 */ 811 if (IS_ERR_OR_NULL(ptr)) 812 return pointer_string(buf, end, ptr, spec); 813 814 /* When debugging early boot use non-cryptographically secure hash. */ 815 if (unlikely(debug_boot_weak_hash)) { 816 hashval = hash_long((unsigned long)ptr, 32); 817 return pointer_string(buf, end, (const void *)hashval, spec); 818 } 819 820 ret = __ptr_to_hashval(ptr, &hashval); 821 if (ret) { 822 spec.field_width = 2 * sizeof(ptr); 823 /* string length must be less than default_width */ 824 return error_string(buf, end, str, spec); 825 } 826 827 return pointer_string(buf, end, (const void *)hashval, spec); 828 } 829 830 static char *default_pointer(char *buf, char *end, const void *ptr, 831 struct printf_spec spec) 832 { 833 /* 834 * default is to _not_ leak addresses, so hash before printing, 835 * unless no_hash_pointers is specified on the command line. 836 */ 837 if (unlikely(no_hash_pointers)) 838 return pointer_string(buf, end, ptr, spec); 839 840 return ptr_to_id(buf, end, ptr, spec); 841 } 842 843 int kptr_restrict __read_mostly; 844 845 static noinline_for_stack 846 char *restricted_pointer(char *buf, char *end, const void *ptr, 847 struct printf_spec spec) 848 { 849 switch (kptr_restrict) { 850 case 0: 851 /* Handle as %p, hash and do _not_ leak addresses. */ 852 return default_pointer(buf, end, ptr, spec); 853 case 1: { 854 const struct cred *cred; 855 856 /* 857 * kptr_restrict==1 cannot be used in IRQ context 858 * because its test for CAP_SYSLOG would be meaningless. 859 */ 860 if (in_hardirq() || in_serving_softirq() || in_nmi()) { 861 if (spec.field_width == -1) 862 spec.field_width = 2 * sizeof(ptr); 863 return error_string(buf, end, "pK-error", spec); 864 } 865 866 /* 867 * Only print the real pointer value if the current 868 * process has CAP_SYSLOG and is running with the 869 * same credentials it started with. This is because 870 * access to files is checked at open() time, but %pK 871 * checks permission at read() time. We don't want to 872 * leak pointer values if a binary opens a file using 873 * %pK and then elevates privileges before reading it. 874 */ 875 cred = current_cred(); 876 if (!has_capability_noaudit(current, CAP_SYSLOG) || 877 !uid_eq(cred->euid, cred->uid) || 878 !gid_eq(cred->egid, cred->gid)) 879 ptr = NULL; 880 break; 881 } 882 case 2: 883 default: 884 /* Always print 0's for %pK */ 885 ptr = NULL; 886 break; 887 } 888 889 return pointer_string(buf, end, ptr, spec); 890 } 891 892 static noinline_for_stack 893 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 894 const char *fmt) 895 { 896 const char *array[4], *s; 897 const struct dentry *p; 898 int depth; 899 int i, n; 900 901 switch (fmt[1]) { 902 case '2': case '3': case '4': 903 depth = fmt[1] - '0'; 904 break; 905 default: 906 depth = 1; 907 } 908 909 rcu_read_lock(); 910 for (i = 0; i < depth; i++, d = p) { 911 if (check_pointer(&buf, end, d, spec)) { 912 rcu_read_unlock(); 913 return buf; 914 } 915 916 p = READ_ONCE(d->d_parent); 917 array[i] = READ_ONCE(d->d_name.name); 918 if (p == d) { 919 if (i) 920 array[i] = ""; 921 i++; 922 break; 923 } 924 } 925 s = array[--i]; 926 for (n = 0; n != spec.precision; n++, buf++) { 927 char c = *s++; 928 if (!c) { 929 if (!i) 930 break; 931 c = '/'; 932 s = array[--i]; 933 } 934 if (buf < end) 935 *buf = c; 936 } 937 rcu_read_unlock(); 938 return widen_string(buf, n, end, spec); 939 } 940 941 static noinline_for_stack 942 char *file_dentry_name(char *buf, char *end, const struct file *f, 943 struct printf_spec spec, const char *fmt) 944 { 945 if (check_pointer(&buf, end, f, spec)) 946 return buf; 947 948 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 949 } 950 #ifdef CONFIG_BLOCK 951 static noinline_for_stack 952 char *bdev_name(char *buf, char *end, struct block_device *bdev, 953 struct printf_spec spec, const char *fmt) 954 { 955 struct gendisk *hd; 956 957 if (check_pointer(&buf, end, bdev, spec)) 958 return buf; 959 960 hd = bdev->bd_disk; 961 buf = string(buf, end, hd->disk_name, spec); 962 if (bdev_is_partition(bdev)) { 963 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 964 if (buf < end) 965 *buf = 'p'; 966 buf++; 967 } 968 buf = number(buf, end, bdev_partno(bdev), spec); 969 } 970 return buf; 971 } 972 #endif 973 974 static noinline_for_stack 975 char *symbol_string(char *buf, char *end, void *ptr, 976 struct printf_spec spec, const char *fmt) 977 { 978 unsigned long value; 979 #ifdef CONFIG_KALLSYMS 980 char sym[KSYM_SYMBOL_LEN]; 981 #endif 982 983 if (fmt[1] == 'R') 984 ptr = __builtin_extract_return_addr(ptr); 985 value = (unsigned long)ptr; 986 987 #ifdef CONFIG_KALLSYMS 988 if (*fmt == 'B' && fmt[1] == 'b') 989 sprint_backtrace_build_id(sym, value); 990 else if (*fmt == 'B') 991 sprint_backtrace(sym, value); 992 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 993 sprint_symbol_build_id(sym, value); 994 else if (*fmt != 's') 995 sprint_symbol(sym, value); 996 else 997 sprint_symbol_no_offset(sym, value); 998 999 return string_nocheck(buf, end, sym, spec); 1000 #else 1001 return special_hex_number(buf, end, value, sizeof(void *)); 1002 #endif 1003 } 1004 1005 static const struct printf_spec default_str_spec = { 1006 .field_width = -1, 1007 .precision = -1, 1008 }; 1009 1010 static const struct printf_spec default_flag_spec = { 1011 .base = 16, 1012 .precision = -1, 1013 .flags = SPECIAL | SMALL, 1014 }; 1015 1016 static const struct printf_spec default_dec_spec = { 1017 .base = 10, 1018 .precision = -1, 1019 }; 1020 1021 static const struct printf_spec default_dec02_spec = { 1022 .base = 10, 1023 .field_width = 2, 1024 .precision = -1, 1025 .flags = ZEROPAD, 1026 }; 1027 1028 static const struct printf_spec default_dec04_spec = { 1029 .base = 10, 1030 .field_width = 4, 1031 .precision = -1, 1032 .flags = ZEROPAD, 1033 }; 1034 1035 static noinline_for_stack 1036 char *hex_range(char *buf, char *end, u64 start_val, u64 end_val, 1037 struct printf_spec spec) 1038 { 1039 buf = number(buf, end, start_val, spec); 1040 if (start_val == end_val) 1041 return buf; 1042 1043 if (buf < end) 1044 *buf = '-'; 1045 ++buf; 1046 return number(buf, end, end_val, spec); 1047 } 1048 1049 static noinline_for_stack 1050 char *resource_string(char *buf, char *end, struct resource *res, 1051 struct printf_spec spec, const char *fmt) 1052 { 1053 #ifndef IO_RSRC_PRINTK_SIZE 1054 #define IO_RSRC_PRINTK_SIZE 6 1055 #endif 1056 1057 #ifndef MEM_RSRC_PRINTK_SIZE 1058 #define MEM_RSRC_PRINTK_SIZE 10 1059 #endif 1060 static const struct printf_spec io_spec = { 1061 .base = 16, 1062 .field_width = IO_RSRC_PRINTK_SIZE, 1063 .precision = -1, 1064 .flags = SPECIAL | SMALL | ZEROPAD, 1065 }; 1066 static const struct printf_spec mem_spec = { 1067 .base = 16, 1068 .field_width = MEM_RSRC_PRINTK_SIZE, 1069 .precision = -1, 1070 .flags = SPECIAL | SMALL | ZEROPAD, 1071 }; 1072 static const struct printf_spec bus_spec = { 1073 .base = 16, 1074 .field_width = 2, 1075 .precision = -1, 1076 .flags = SMALL | ZEROPAD, 1077 }; 1078 static const struct printf_spec str_spec = { 1079 .field_width = -1, 1080 .precision = 10, 1081 .flags = LEFT, 1082 }; 1083 1084 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1085 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1086 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1087 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1088 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1089 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1090 char sym[MAX(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1091 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1092 1093 char *p = sym, *pend = sym + sizeof(sym); 1094 int decode = (fmt[0] == 'R') ? 1 : 0; 1095 const struct printf_spec *specp; 1096 1097 if (check_pointer(&buf, end, res, spec)) 1098 return buf; 1099 1100 *p++ = '['; 1101 if (res->flags & IORESOURCE_IO) { 1102 p = string_nocheck(p, pend, "io ", str_spec); 1103 specp = &io_spec; 1104 } else if (res->flags & IORESOURCE_MEM) { 1105 p = string_nocheck(p, pend, "mem ", str_spec); 1106 specp = &mem_spec; 1107 } else if (res->flags & IORESOURCE_IRQ) { 1108 p = string_nocheck(p, pend, "irq ", str_spec); 1109 specp = &default_dec_spec; 1110 } else if (res->flags & IORESOURCE_DMA) { 1111 p = string_nocheck(p, pend, "dma ", str_spec); 1112 specp = &default_dec_spec; 1113 } else if (res->flags & IORESOURCE_BUS) { 1114 p = string_nocheck(p, pend, "bus ", str_spec); 1115 specp = &bus_spec; 1116 } else { 1117 p = string_nocheck(p, pend, "??? ", str_spec); 1118 specp = &mem_spec; 1119 decode = 0; 1120 } 1121 if (decode && res->flags & IORESOURCE_UNSET) { 1122 p = string_nocheck(p, pend, "size ", str_spec); 1123 p = number(p, pend, resource_size(res), *specp); 1124 } else { 1125 p = hex_range(p, pend, res->start, res->end, *specp); 1126 } 1127 if (decode) { 1128 if (res->flags & IORESOURCE_MEM_64) 1129 p = string_nocheck(p, pend, " 64bit", str_spec); 1130 if (res->flags & IORESOURCE_PREFETCH) 1131 p = string_nocheck(p, pend, " pref", str_spec); 1132 if (res->flags & IORESOURCE_WINDOW) 1133 p = string_nocheck(p, pend, " window", str_spec); 1134 if (res->flags & IORESOURCE_DISABLED) 1135 p = string_nocheck(p, pend, " disabled", str_spec); 1136 } else { 1137 p = string_nocheck(p, pend, " flags ", str_spec); 1138 p = number(p, pend, res->flags, default_flag_spec); 1139 } 1140 *p++ = ']'; 1141 *p = '\0'; 1142 1143 return string_nocheck(buf, end, sym, spec); 1144 } 1145 1146 static noinline_for_stack 1147 char *range_string(char *buf, char *end, const struct range *range, 1148 struct printf_spec spec, const char *fmt) 1149 { 1150 char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")]; 1151 char *p = sym, *pend = sym + sizeof(sym); 1152 1153 struct printf_spec range_spec = { 1154 .field_width = 2 + 2 * sizeof(range->start), /* 0x + 2 * 8 */ 1155 .flags = SPECIAL | SMALL | ZEROPAD, 1156 .base = 16, 1157 .precision = -1, 1158 }; 1159 1160 if (check_pointer(&buf, end, range, spec)) 1161 return buf; 1162 1163 p = string_nocheck(p, pend, "[range ", default_str_spec); 1164 p = hex_range(p, pend, range->start, range->end, range_spec); 1165 *p++ = ']'; 1166 *p = '\0'; 1167 1168 return string_nocheck(buf, end, sym, spec); 1169 } 1170 1171 static noinline_for_stack 1172 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1173 const char *fmt) 1174 { 1175 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1176 negative value, fallback to the default */ 1177 char separator; 1178 1179 if (spec.field_width == 0) 1180 /* nothing to print */ 1181 return buf; 1182 1183 if (check_pointer(&buf, end, addr, spec)) 1184 return buf; 1185 1186 switch (fmt[1]) { 1187 case 'C': 1188 separator = ':'; 1189 break; 1190 case 'D': 1191 separator = '-'; 1192 break; 1193 case 'N': 1194 separator = 0; 1195 break; 1196 default: 1197 separator = ' '; 1198 break; 1199 } 1200 1201 if (spec.field_width > 0) 1202 len = min_t(int, spec.field_width, 64); 1203 1204 for (i = 0; i < len; ++i) { 1205 if (buf < end) 1206 *buf = hex_asc_hi(addr[i]); 1207 ++buf; 1208 if (buf < end) 1209 *buf = hex_asc_lo(addr[i]); 1210 ++buf; 1211 1212 if (separator && i != len - 1) { 1213 if (buf < end) 1214 *buf = separator; 1215 ++buf; 1216 } 1217 } 1218 1219 return buf; 1220 } 1221 1222 static noinline_for_stack 1223 char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, 1224 struct printf_spec spec, const char *fmt) 1225 { 1226 const int CHUNKSZ = 32; 1227 int nr_bits = max_t(int, spec.field_width, 0); 1228 int i, chunksz; 1229 bool first = true; 1230 1231 if (check_pointer(&buf, end, bitmap, spec)) 1232 return buf; 1233 1234 /* reused to print numbers */ 1235 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1236 1237 chunksz = nr_bits & (CHUNKSZ - 1); 1238 if (chunksz == 0) 1239 chunksz = CHUNKSZ; 1240 1241 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1242 for (; i >= 0; i -= CHUNKSZ) { 1243 u32 chunkmask, val; 1244 int word, bit; 1245 1246 chunkmask = ((1ULL << chunksz) - 1); 1247 word = i / BITS_PER_LONG; 1248 bit = i % BITS_PER_LONG; 1249 val = (bitmap[word] >> bit) & chunkmask; 1250 1251 if (!first) { 1252 if (buf < end) 1253 *buf = ','; 1254 buf++; 1255 } 1256 first = false; 1257 1258 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1259 buf = number(buf, end, val, spec); 1260 1261 chunksz = CHUNKSZ; 1262 } 1263 return buf; 1264 } 1265 1266 static noinline_for_stack 1267 char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, 1268 struct printf_spec spec, const char *fmt) 1269 { 1270 int nr_bits = max_t(int, spec.field_width, 0); 1271 bool first = true; 1272 int rbot, rtop; 1273 1274 if (check_pointer(&buf, end, bitmap, spec)) 1275 return buf; 1276 1277 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1278 if (!first) { 1279 if (buf < end) 1280 *buf = ','; 1281 buf++; 1282 } 1283 first = false; 1284 1285 buf = number(buf, end, rbot, default_dec_spec); 1286 if (rtop == rbot + 1) 1287 continue; 1288 1289 if (buf < end) 1290 *buf = '-'; 1291 buf = number(++buf, end, rtop - 1, default_dec_spec); 1292 } 1293 return buf; 1294 } 1295 1296 static noinline_for_stack 1297 char *mac_address_string(char *buf, char *end, u8 *addr, 1298 struct printf_spec spec, const char *fmt) 1299 { 1300 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1301 char *p = mac_addr; 1302 int i; 1303 char separator; 1304 bool reversed = false; 1305 1306 if (check_pointer(&buf, end, addr, spec)) 1307 return buf; 1308 1309 switch (fmt[1]) { 1310 case 'F': 1311 separator = '-'; 1312 break; 1313 1314 case 'R': 1315 reversed = true; 1316 fallthrough; 1317 1318 default: 1319 separator = ':'; 1320 break; 1321 } 1322 1323 for (i = 0; i < 6; i++) { 1324 if (reversed) 1325 p = hex_byte_pack(p, addr[5 - i]); 1326 else 1327 p = hex_byte_pack(p, addr[i]); 1328 1329 if (fmt[0] == 'M' && i != 5) 1330 *p++ = separator; 1331 } 1332 *p = '\0'; 1333 1334 return string_nocheck(buf, end, mac_addr, spec); 1335 } 1336 1337 static noinline_for_stack 1338 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1339 { 1340 int i; 1341 bool leading_zeros = (fmt[0] == 'i'); 1342 int index; 1343 int step; 1344 1345 switch (fmt[2]) { 1346 case 'h': 1347 #ifdef __BIG_ENDIAN 1348 index = 0; 1349 step = 1; 1350 #else 1351 index = 3; 1352 step = -1; 1353 #endif 1354 break; 1355 case 'l': 1356 index = 3; 1357 step = -1; 1358 break; 1359 case 'n': 1360 case 'b': 1361 default: 1362 index = 0; 1363 step = 1; 1364 break; 1365 } 1366 for (i = 0; i < 4; i++) { 1367 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1368 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1369 if (leading_zeros) { 1370 if (digits < 3) 1371 *p++ = '0'; 1372 if (digits < 2) 1373 *p++ = '0'; 1374 } 1375 /* reverse the digits in the quad */ 1376 while (digits--) 1377 *p++ = temp[digits]; 1378 if (i < 3) 1379 *p++ = '.'; 1380 index += step; 1381 } 1382 *p = '\0'; 1383 1384 return p; 1385 } 1386 1387 static noinline_for_stack 1388 char *ip6_compressed_string(char *p, const char *addr) 1389 { 1390 int i, j, range; 1391 unsigned char zerolength[8]; 1392 int longest = 1; 1393 int colonpos = -1; 1394 u16 word; 1395 u8 hi, lo; 1396 bool needcolon = false; 1397 bool useIPv4; 1398 struct in6_addr in6; 1399 1400 memcpy(&in6, addr, sizeof(struct in6_addr)); 1401 1402 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1403 1404 memset(zerolength, 0, sizeof(zerolength)); 1405 1406 if (useIPv4) 1407 range = 6; 1408 else 1409 range = 8; 1410 1411 /* find position of longest 0 run */ 1412 for (i = 0; i < range; i++) { 1413 for (j = i; j < range; j++) { 1414 if (in6.s6_addr16[j] != 0) 1415 break; 1416 zerolength[i]++; 1417 } 1418 } 1419 for (i = 0; i < range; i++) { 1420 if (zerolength[i] > longest) { 1421 longest = zerolength[i]; 1422 colonpos = i; 1423 } 1424 } 1425 if (longest == 1) /* don't compress a single 0 */ 1426 colonpos = -1; 1427 1428 /* emit address */ 1429 for (i = 0; i < range; i++) { 1430 if (i == colonpos) { 1431 if (needcolon || i == 0) 1432 *p++ = ':'; 1433 *p++ = ':'; 1434 needcolon = false; 1435 i += longest - 1; 1436 continue; 1437 } 1438 if (needcolon) { 1439 *p++ = ':'; 1440 needcolon = false; 1441 } 1442 /* hex u16 without leading 0s */ 1443 word = ntohs(in6.s6_addr16[i]); 1444 hi = word >> 8; 1445 lo = word & 0xff; 1446 if (hi) { 1447 if (hi > 0x0f) 1448 p = hex_byte_pack(p, hi); 1449 else 1450 *p++ = hex_asc_lo(hi); 1451 p = hex_byte_pack(p, lo); 1452 } 1453 else if (lo > 0x0f) 1454 p = hex_byte_pack(p, lo); 1455 else 1456 *p++ = hex_asc_lo(lo); 1457 needcolon = true; 1458 } 1459 1460 if (useIPv4) { 1461 if (needcolon) 1462 *p++ = ':'; 1463 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1464 } 1465 *p = '\0'; 1466 1467 return p; 1468 } 1469 1470 static noinline_for_stack 1471 char *ip6_string(char *p, const char *addr, const char *fmt) 1472 { 1473 int i; 1474 1475 for (i = 0; i < 8; i++) { 1476 p = hex_byte_pack(p, *addr++); 1477 p = hex_byte_pack(p, *addr++); 1478 if (fmt[0] == 'I' && i != 7) 1479 *p++ = ':'; 1480 } 1481 *p = '\0'; 1482 1483 return p; 1484 } 1485 1486 static noinline_for_stack 1487 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1488 struct printf_spec spec, const char *fmt) 1489 { 1490 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1491 1492 if (fmt[0] == 'I' && fmt[2] == 'c') 1493 ip6_compressed_string(ip6_addr, addr); 1494 else 1495 ip6_string(ip6_addr, addr, fmt); 1496 1497 return string_nocheck(buf, end, ip6_addr, spec); 1498 } 1499 1500 static noinline_for_stack 1501 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1502 struct printf_spec spec, const char *fmt) 1503 { 1504 char ip4_addr[sizeof("255.255.255.255")]; 1505 1506 ip4_string(ip4_addr, addr, fmt); 1507 1508 return string_nocheck(buf, end, ip4_addr, spec); 1509 } 1510 1511 static noinline_for_stack 1512 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1513 struct printf_spec spec, const char *fmt) 1514 { 1515 bool have_p = false, have_s = false, have_f = false, have_c = false; 1516 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1517 sizeof(":12345") + sizeof("/123456789") + 1518 sizeof("%1234567890")]; 1519 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1520 const u8 *addr = (const u8 *) &sa->sin6_addr; 1521 char fmt6[2] = { fmt[0], '6' }; 1522 u8 off = 0; 1523 1524 fmt++; 1525 while (isalpha(*++fmt)) { 1526 switch (*fmt) { 1527 case 'p': 1528 have_p = true; 1529 break; 1530 case 'f': 1531 have_f = true; 1532 break; 1533 case 's': 1534 have_s = true; 1535 break; 1536 case 'c': 1537 have_c = true; 1538 break; 1539 } 1540 } 1541 1542 if (have_p || have_s || have_f) { 1543 *p = '['; 1544 off = 1; 1545 } 1546 1547 if (fmt6[0] == 'I' && have_c) 1548 p = ip6_compressed_string(ip6_addr + off, addr); 1549 else 1550 p = ip6_string(ip6_addr + off, addr, fmt6); 1551 1552 if (have_p || have_s || have_f) 1553 *p++ = ']'; 1554 1555 if (have_p) { 1556 *p++ = ':'; 1557 p = number(p, pend, ntohs(sa->sin6_port), spec); 1558 } 1559 if (have_f) { 1560 *p++ = '/'; 1561 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1562 IPV6_FLOWINFO_MASK), spec); 1563 } 1564 if (have_s) { 1565 *p++ = '%'; 1566 p = number(p, pend, sa->sin6_scope_id, spec); 1567 } 1568 *p = '\0'; 1569 1570 return string_nocheck(buf, end, ip6_addr, spec); 1571 } 1572 1573 static noinline_for_stack 1574 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1575 struct printf_spec spec, const char *fmt) 1576 { 1577 bool have_p = false; 1578 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1579 char *pend = ip4_addr + sizeof(ip4_addr); 1580 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1581 char fmt4[3] = { fmt[0], '4', 0 }; 1582 1583 fmt++; 1584 while (isalpha(*++fmt)) { 1585 switch (*fmt) { 1586 case 'p': 1587 have_p = true; 1588 break; 1589 case 'h': 1590 case 'l': 1591 case 'n': 1592 case 'b': 1593 fmt4[2] = *fmt; 1594 break; 1595 } 1596 } 1597 1598 p = ip4_string(ip4_addr, addr, fmt4); 1599 if (have_p) { 1600 *p++ = ':'; 1601 p = number(p, pend, ntohs(sa->sin_port), spec); 1602 } 1603 *p = '\0'; 1604 1605 return string_nocheck(buf, end, ip4_addr, spec); 1606 } 1607 1608 static noinline_for_stack 1609 char *ip_addr_string(char *buf, char *end, const void *ptr, 1610 struct printf_spec spec, const char *fmt) 1611 { 1612 char *err_fmt_msg; 1613 1614 if (check_pointer(&buf, end, ptr, spec)) 1615 return buf; 1616 1617 switch (fmt[1]) { 1618 case '6': 1619 return ip6_addr_string(buf, end, ptr, spec, fmt); 1620 case '4': 1621 return ip4_addr_string(buf, end, ptr, spec, fmt); 1622 case 'S': { 1623 const union { 1624 struct sockaddr raw; 1625 struct sockaddr_in v4; 1626 struct sockaddr_in6 v6; 1627 } *sa = ptr; 1628 1629 switch (sa->raw.sa_family) { 1630 case AF_INET: 1631 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1632 case AF_INET6: 1633 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1634 default: 1635 return error_string(buf, end, "(einval)", spec); 1636 }} 1637 } 1638 1639 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1640 return error_string(buf, end, err_fmt_msg, spec); 1641 } 1642 1643 static noinline_for_stack 1644 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1645 const char *fmt) 1646 { 1647 bool found = true; 1648 int count = 1; 1649 unsigned int flags = 0; 1650 int len; 1651 1652 if (spec.field_width == 0) 1653 return buf; /* nothing to print */ 1654 1655 if (check_pointer(&buf, end, addr, spec)) 1656 return buf; 1657 1658 do { 1659 switch (fmt[count++]) { 1660 case 'a': 1661 flags |= ESCAPE_ANY; 1662 break; 1663 case 'c': 1664 flags |= ESCAPE_SPECIAL; 1665 break; 1666 case 'h': 1667 flags |= ESCAPE_HEX; 1668 break; 1669 case 'n': 1670 flags |= ESCAPE_NULL; 1671 break; 1672 case 'o': 1673 flags |= ESCAPE_OCTAL; 1674 break; 1675 case 'p': 1676 flags |= ESCAPE_NP; 1677 break; 1678 case 's': 1679 flags |= ESCAPE_SPACE; 1680 break; 1681 default: 1682 found = false; 1683 break; 1684 } 1685 } while (found); 1686 1687 if (!flags) 1688 flags = ESCAPE_ANY_NP; 1689 1690 len = spec.field_width < 0 ? 1 : spec.field_width; 1691 1692 /* 1693 * string_escape_mem() writes as many characters as it can to 1694 * the given buffer, and returns the total size of the output 1695 * had the buffer been big enough. 1696 */ 1697 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1698 1699 return buf; 1700 } 1701 1702 #pragma GCC diagnostic push 1703 #ifndef __clang__ 1704 #pragma GCC diagnostic ignored "-Wsuggest-attribute=format" 1705 #endif 1706 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1707 struct printf_spec spec) 1708 { 1709 va_list va; 1710 1711 if (check_pointer(&buf, end, va_fmt, spec)) 1712 return buf; 1713 1714 va_copy(va, *va_fmt->va); 1715 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1716 va_end(va); 1717 1718 return buf; 1719 } 1720 #pragma GCC diagnostic pop 1721 1722 static noinline_for_stack 1723 char *uuid_string(char *buf, char *end, const u8 *addr, 1724 struct printf_spec spec, const char *fmt) 1725 { 1726 char uuid[UUID_STRING_LEN + 1]; 1727 char *p = uuid; 1728 int i; 1729 const u8 *index = uuid_index; 1730 bool uc = false; 1731 1732 if (check_pointer(&buf, end, addr, spec)) 1733 return buf; 1734 1735 switch (*(++fmt)) { 1736 case 'L': 1737 uc = true; 1738 fallthrough; 1739 case 'l': 1740 index = guid_index; 1741 break; 1742 case 'B': 1743 uc = true; 1744 break; 1745 } 1746 1747 for (i = 0; i < 16; i++) { 1748 if (uc) 1749 p = hex_byte_pack_upper(p, addr[index[i]]); 1750 else 1751 p = hex_byte_pack(p, addr[index[i]]); 1752 switch (i) { 1753 case 3: 1754 case 5: 1755 case 7: 1756 case 9: 1757 *p++ = '-'; 1758 break; 1759 } 1760 } 1761 1762 *p = 0; 1763 1764 return string_nocheck(buf, end, uuid, spec); 1765 } 1766 1767 static noinline_for_stack 1768 char *netdev_bits(char *buf, char *end, const void *addr, 1769 struct printf_spec spec, const char *fmt) 1770 { 1771 unsigned long long num; 1772 int size; 1773 1774 if (check_pointer(&buf, end, addr, spec)) 1775 return buf; 1776 1777 switch (fmt[1]) { 1778 case 'F': 1779 num = *(const netdev_features_t *)addr; 1780 size = sizeof(netdev_features_t); 1781 break; 1782 default: 1783 return error_string(buf, end, "(%pN?)", spec); 1784 } 1785 1786 return special_hex_number(buf, end, num, size); 1787 } 1788 1789 static noinline_for_stack 1790 char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1791 struct printf_spec spec, const char *fmt) 1792 { 1793 char output[sizeof("0123 little-endian (0x01234567)")]; 1794 char *p = output; 1795 unsigned int i; 1796 u32 orig, val; 1797 1798 if (fmt[1] != 'c' || fmt[2] != 'c') 1799 return error_string(buf, end, "(%p4?)", spec); 1800 1801 if (check_pointer(&buf, end, fourcc, spec)) 1802 return buf; 1803 1804 orig = get_unaligned(fourcc); 1805 val = orig & ~BIT(31); 1806 1807 for (i = 0; i < sizeof(u32); i++) { 1808 unsigned char c = val >> (i * 8); 1809 1810 /* Print non-control ASCII characters as-is, dot otherwise */ 1811 *p++ = isascii(c) && isprint(c) ? c : '.'; 1812 } 1813 1814 *p++ = ' '; 1815 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1816 p += strlen(p); 1817 1818 *p++ = ' '; 1819 *p++ = '('; 1820 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1821 *p++ = ')'; 1822 *p = '\0'; 1823 1824 return string(buf, end, output, spec); 1825 } 1826 1827 static noinline_for_stack 1828 char *address_val(char *buf, char *end, const void *addr, 1829 struct printf_spec spec, const char *fmt) 1830 { 1831 unsigned long long num; 1832 int size; 1833 1834 if (check_pointer(&buf, end, addr, spec)) 1835 return buf; 1836 1837 switch (fmt[1]) { 1838 case 'd': 1839 num = *(const dma_addr_t *)addr; 1840 size = sizeof(dma_addr_t); 1841 break; 1842 case 'p': 1843 default: 1844 num = *(const phys_addr_t *)addr; 1845 size = sizeof(phys_addr_t); 1846 break; 1847 } 1848 1849 return special_hex_number(buf, end, num, size); 1850 } 1851 1852 static noinline_for_stack 1853 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1854 { 1855 int year = tm->tm_year + (r ? 0 : 1900); 1856 int mon = tm->tm_mon + (r ? 0 : 1); 1857 1858 buf = number(buf, end, year, default_dec04_spec); 1859 if (buf < end) 1860 *buf = '-'; 1861 buf++; 1862 1863 buf = number(buf, end, mon, default_dec02_spec); 1864 if (buf < end) 1865 *buf = '-'; 1866 buf++; 1867 1868 return number(buf, end, tm->tm_mday, default_dec02_spec); 1869 } 1870 1871 static noinline_for_stack 1872 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1873 { 1874 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1875 if (buf < end) 1876 *buf = ':'; 1877 buf++; 1878 1879 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1880 if (buf < end) 1881 *buf = ':'; 1882 buf++; 1883 1884 return number(buf, end, tm->tm_sec, default_dec02_spec); 1885 } 1886 1887 static noinline_for_stack 1888 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1889 struct printf_spec spec, const char *fmt) 1890 { 1891 bool have_t = true, have_d = true; 1892 bool raw = false, iso8601_separator = true; 1893 bool found = true; 1894 int count = 2; 1895 1896 if (check_pointer(&buf, end, tm, spec)) 1897 return buf; 1898 1899 switch (fmt[count]) { 1900 case 'd': 1901 have_t = false; 1902 count++; 1903 break; 1904 case 't': 1905 have_d = false; 1906 count++; 1907 break; 1908 } 1909 1910 do { 1911 switch (fmt[count++]) { 1912 case 'r': 1913 raw = true; 1914 break; 1915 case 's': 1916 iso8601_separator = false; 1917 break; 1918 default: 1919 found = false; 1920 break; 1921 } 1922 } while (found); 1923 1924 if (have_d) 1925 buf = date_str(buf, end, tm, raw); 1926 if (have_d && have_t) { 1927 if (buf < end) 1928 *buf = iso8601_separator ? 'T' : ' '; 1929 buf++; 1930 } 1931 if (have_t) 1932 buf = time_str(buf, end, tm, raw); 1933 1934 return buf; 1935 } 1936 1937 static noinline_for_stack 1938 char *time64_str(char *buf, char *end, const time64_t time, 1939 struct printf_spec spec, const char *fmt) 1940 { 1941 struct rtc_time rtc_time; 1942 struct tm tm; 1943 1944 time64_to_tm(time, 0, &tm); 1945 1946 rtc_time.tm_sec = tm.tm_sec; 1947 rtc_time.tm_min = tm.tm_min; 1948 rtc_time.tm_hour = tm.tm_hour; 1949 rtc_time.tm_mday = tm.tm_mday; 1950 rtc_time.tm_mon = tm.tm_mon; 1951 rtc_time.tm_year = tm.tm_year; 1952 rtc_time.tm_wday = tm.tm_wday; 1953 rtc_time.tm_yday = tm.tm_yday; 1954 1955 rtc_time.tm_isdst = 0; 1956 1957 return rtc_str(buf, end, &rtc_time, spec, fmt); 1958 } 1959 1960 static noinline_for_stack 1961 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1962 const char *fmt) 1963 { 1964 switch (fmt[1]) { 1965 case 'R': 1966 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1967 case 'T': 1968 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 1969 default: 1970 return error_string(buf, end, "(%pt?)", spec); 1971 } 1972 } 1973 1974 static noinline_for_stack 1975 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1976 const char *fmt) 1977 { 1978 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1979 return error_string(buf, end, "(%pC?)", spec); 1980 1981 if (check_pointer(&buf, end, clk, spec)) 1982 return buf; 1983 1984 switch (fmt[1]) { 1985 case 'n': 1986 default: 1987 #ifdef CONFIG_COMMON_CLK 1988 return string(buf, end, __clk_get_name(clk), spec); 1989 #else 1990 return ptr_to_id(buf, end, clk, spec); 1991 #endif 1992 } 1993 } 1994 1995 static 1996 char *format_flags(char *buf, char *end, unsigned long flags, 1997 const struct trace_print_flags *names) 1998 { 1999 unsigned long mask; 2000 2001 for ( ; flags && names->name; names++) { 2002 mask = names->mask; 2003 if ((flags & mask) != mask) 2004 continue; 2005 2006 buf = string(buf, end, names->name, default_str_spec); 2007 2008 flags &= ~mask; 2009 if (flags) { 2010 if (buf < end) 2011 *buf = '|'; 2012 buf++; 2013 } 2014 } 2015 2016 if (flags) 2017 buf = number(buf, end, flags, default_flag_spec); 2018 2019 return buf; 2020 } 2021 2022 struct page_flags_fields { 2023 int width; 2024 int shift; 2025 int mask; 2026 const struct printf_spec *spec; 2027 const char *name; 2028 }; 2029 2030 static const struct page_flags_fields pff[] = { 2031 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 2032 &default_dec_spec, "section"}, 2033 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2034 &default_dec_spec, "node"}, 2035 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2036 &default_dec_spec, "zone"}, 2037 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2038 &default_flag_spec, "lastcpupid"}, 2039 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2040 &default_flag_spec, "kasantag"}, 2041 }; 2042 2043 static 2044 char *format_page_flags(char *buf, char *end, unsigned long flags) 2045 { 2046 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2047 bool append = false; 2048 int i; 2049 2050 buf = number(buf, end, flags, default_flag_spec); 2051 if (buf < end) 2052 *buf = '('; 2053 buf++; 2054 2055 /* Page flags from the main area. */ 2056 if (main_flags) { 2057 buf = format_flags(buf, end, main_flags, pageflag_names); 2058 append = true; 2059 } 2060 2061 /* Page flags from the fields area */ 2062 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2063 /* Skip undefined fields. */ 2064 if (!pff[i].width) 2065 continue; 2066 2067 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2068 if (append) { 2069 if (buf < end) 2070 *buf = '|'; 2071 buf++; 2072 } 2073 2074 buf = string(buf, end, pff[i].name, default_str_spec); 2075 if (buf < end) 2076 *buf = '='; 2077 buf++; 2078 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2079 *pff[i].spec); 2080 2081 append = true; 2082 } 2083 if (buf < end) 2084 *buf = ')'; 2085 buf++; 2086 2087 return buf; 2088 } 2089 2090 static noinline_for_stack 2091 char *flags_string(char *buf, char *end, void *flags_ptr, 2092 struct printf_spec spec, const char *fmt) 2093 { 2094 unsigned long flags; 2095 const struct trace_print_flags *names; 2096 2097 if (check_pointer(&buf, end, flags_ptr, spec)) 2098 return buf; 2099 2100 switch (fmt[1]) { 2101 case 'p': 2102 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2103 case 'v': 2104 flags = *(unsigned long *)flags_ptr; 2105 names = vmaflag_names; 2106 break; 2107 case 'g': 2108 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2109 names = gfpflag_names; 2110 break; 2111 default: 2112 return error_string(buf, end, "(%pG?)", spec); 2113 } 2114 2115 return format_flags(buf, end, flags, names); 2116 } 2117 2118 static noinline_for_stack 2119 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2120 char *end) 2121 { 2122 int depth; 2123 2124 /* Loop starting from the root node to the current node. */ 2125 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2126 /* 2127 * Only get a reference for other nodes (i.e. parent nodes). 2128 * fwnode refcount may be 0 here. 2129 */ 2130 struct fwnode_handle *__fwnode = depth ? 2131 fwnode_get_nth_parent(fwnode, depth) : fwnode; 2132 2133 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2134 default_str_spec); 2135 buf = string(buf, end, fwnode_get_name(__fwnode), 2136 default_str_spec); 2137 2138 if (depth) 2139 fwnode_handle_put(__fwnode); 2140 } 2141 2142 return buf; 2143 } 2144 2145 static noinline_for_stack 2146 char *device_node_string(char *buf, char *end, struct device_node *dn, 2147 struct printf_spec spec, const char *fmt) 2148 { 2149 char tbuf[sizeof("xxxx") + 1]; 2150 const char *p; 2151 int ret; 2152 char *buf_start = buf; 2153 struct property *prop; 2154 bool has_mult, pass; 2155 2156 struct printf_spec str_spec = spec; 2157 str_spec.field_width = -1; 2158 2159 if (fmt[0] != 'F') 2160 return error_string(buf, end, "(%pO?)", spec); 2161 2162 if (!IS_ENABLED(CONFIG_OF)) 2163 return error_string(buf, end, "(%pOF?)", spec); 2164 2165 if (check_pointer(&buf, end, dn, spec)) 2166 return buf; 2167 2168 /* simple case without anything any more format specifiers */ 2169 fmt++; 2170 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2171 fmt = "f"; 2172 2173 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2174 int precision; 2175 if (pass) { 2176 if (buf < end) 2177 *buf = ':'; 2178 buf++; 2179 } 2180 2181 switch (*fmt) { 2182 case 'f': /* full_name */ 2183 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2184 end); 2185 break; 2186 case 'n': /* name */ 2187 p = fwnode_get_name(of_fwnode_handle(dn)); 2188 precision = str_spec.precision; 2189 str_spec.precision = strchrnul(p, '@') - p; 2190 buf = string(buf, end, p, str_spec); 2191 str_spec.precision = precision; 2192 break; 2193 case 'p': /* phandle */ 2194 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2195 break; 2196 case 'P': /* path-spec */ 2197 p = fwnode_get_name(of_fwnode_handle(dn)); 2198 if (!p[1]) 2199 p = "/"; 2200 buf = string(buf, end, p, str_spec); 2201 break; 2202 case 'F': /* flags */ 2203 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2204 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2205 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2206 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2207 tbuf[4] = 0; 2208 buf = string_nocheck(buf, end, tbuf, str_spec); 2209 break; 2210 case 'c': /* major compatible string */ 2211 ret = of_property_read_string(dn, "compatible", &p); 2212 if (!ret) 2213 buf = string(buf, end, p, str_spec); 2214 break; 2215 case 'C': /* full compatible string */ 2216 has_mult = false; 2217 of_property_for_each_string(dn, "compatible", prop, p) { 2218 if (has_mult) 2219 buf = string_nocheck(buf, end, ",", str_spec); 2220 buf = string_nocheck(buf, end, "\"", str_spec); 2221 buf = string(buf, end, p, str_spec); 2222 buf = string_nocheck(buf, end, "\"", str_spec); 2223 2224 has_mult = true; 2225 } 2226 break; 2227 default: 2228 break; 2229 } 2230 } 2231 2232 return widen_string(buf, buf - buf_start, end, spec); 2233 } 2234 2235 static noinline_for_stack 2236 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2237 struct printf_spec spec, const char *fmt) 2238 { 2239 struct printf_spec str_spec = spec; 2240 char *buf_start = buf; 2241 2242 str_spec.field_width = -1; 2243 2244 if (*fmt != 'w') 2245 return error_string(buf, end, "(%pf?)", spec); 2246 2247 if (check_pointer(&buf, end, fwnode, spec)) 2248 return buf; 2249 2250 fmt++; 2251 2252 switch (*fmt) { 2253 case 'P': /* name */ 2254 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2255 break; 2256 case 'f': /* full_name */ 2257 default: 2258 buf = fwnode_full_name_string(fwnode, buf, end); 2259 break; 2260 } 2261 2262 return widen_string(buf, buf - buf_start, end, spec); 2263 } 2264 2265 static noinline_for_stack 2266 char *resource_or_range(const char *fmt, char *buf, char *end, void *ptr, 2267 struct printf_spec spec) 2268 { 2269 if (*fmt == 'r' && fmt[1] == 'a') 2270 return range_string(buf, end, ptr, spec, fmt); 2271 return resource_string(buf, end, ptr, spec, fmt); 2272 } 2273 2274 int __init no_hash_pointers_enable(char *str) 2275 { 2276 if (no_hash_pointers) 2277 return 0; 2278 2279 no_hash_pointers = true; 2280 2281 pr_warn("**********************************************************\n"); 2282 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2283 pr_warn("** **\n"); 2284 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2285 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2286 pr_warn("** might reduce the security of your system. **\n"); 2287 pr_warn("** **\n"); 2288 pr_warn("** If you see this message and you are not debugging **\n"); 2289 pr_warn("** the kernel, report this immediately to your system **\n"); 2290 pr_warn("** administrator! **\n"); 2291 pr_warn("** **\n"); 2292 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2293 pr_warn("**********************************************************\n"); 2294 2295 return 0; 2296 } 2297 early_param("no_hash_pointers", no_hash_pointers_enable); 2298 2299 /* 2300 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2301 * by an extra set of alphanumeric characters that are extended format 2302 * specifiers. 2303 * 2304 * Please update scripts/checkpatch.pl when adding/removing conversion 2305 * characters. (Search for "check for vsprintf extension"). 2306 * 2307 * Right now we handle: 2308 * 2309 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2310 * - 's' For symbolic direct pointers (or function descriptors) without offset 2311 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2312 * - 'S[R]b' as above with module build ID (for use in backtraces) 2313 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2314 * %ps and %pS. Be careful when re-using these specifiers. 2315 * - 'B' For backtraced symbolic direct pointers with offset 2316 * - 'Bb' as above with module build ID (for use in backtraces) 2317 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2318 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2319 * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] 2320 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2321 * width which must be explicitly specified either as part of the 2322 * format string '%32b[l]' or through '%*b[l]', [l] selects 2323 * range-list format instead of hex format 2324 * - 'M' For a 6-byte MAC address, it prints the address in the 2325 * usual colon-separated hex notation 2326 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2327 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2328 * with a dash-separated hex notation 2329 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2330 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2331 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2332 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2333 * [S][pfs] 2334 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2335 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2336 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2337 * IPv6 omits the colons (01020304...0f) 2338 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2339 * [S][pfs] 2340 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2341 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2342 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2343 * - 'I[6S]c' for IPv6 addresses printed as specified by 2344 * https://tools.ietf.org/html/rfc5952 2345 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2346 * of the following flags (see string_escape_mem() for the 2347 * details): 2348 * a - ESCAPE_ANY 2349 * c - ESCAPE_SPECIAL 2350 * h - ESCAPE_HEX 2351 * n - ESCAPE_NULL 2352 * o - ESCAPE_OCTAL 2353 * p - ESCAPE_NP 2354 * s - ESCAPE_SPACE 2355 * By default ESCAPE_ANY_NP is used. 2356 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2357 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2358 * Options for %pU are: 2359 * b big endian lower case hex (default) 2360 * B big endian UPPER case hex 2361 * l little endian lower case hex 2362 * L little endian UPPER case hex 2363 * big endian output byte order is: 2364 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2365 * little endian output byte order is: 2366 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2367 * - 'V' For a struct va_format which contains a format string * and va_list *, 2368 * call vsnprintf(->format, *->va_list). 2369 * Implements a "recursive vsnprintf". 2370 * Do not use this feature without some mechanism to verify the 2371 * correctness of the format string and va_list arguments. 2372 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2373 * Use only for procfs, sysfs and similar files, not printk(); please 2374 * read the documentation (path below) first. 2375 * - 'NF' For a netdev_features_t 2376 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2377 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2378 * a certain separator (' ' by default): 2379 * C colon 2380 * D dash 2381 * N no separator 2382 * The maximum supported length is 64 bytes of the input. Consider 2383 * to use print_hex_dump() for the larger input. 2384 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2385 * (default assumed to be phys_addr_t, passed by reference) 2386 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2387 * - 'D[234]' Same as 'd' but for a struct file 2388 * - 'g' For block_device name (gendisk + partition number) 2389 * - 't[RT][dt][r][s]' For time and date as represented by: 2390 * R struct rtc_time 2391 * T time64_t 2392 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2393 * (legacy clock framework) of the clock 2394 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2395 * (legacy clock framework) of the clock 2396 * - 'G' For flags to be printed as a collection of symbolic strings that would 2397 * construct the specific value. Supported flags given by option: 2398 * p page flags (see struct page) given as pointer to unsigned long 2399 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2400 * v vma flags (VM_*) given as pointer to unsigned long 2401 * - 'OF[fnpPcCF]' For a device tree object 2402 * Without any optional arguments prints the full_name 2403 * f device node full_name 2404 * n device node name 2405 * p device node phandle 2406 * P device node path spec (name + @unit) 2407 * F device node flags 2408 * c major compatible string 2409 * C full compatible string 2410 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2411 * Without an option prints the full name of the node 2412 * f full name 2413 * P node name, including a possible unit address 2414 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2415 * Please read the documentation (path below) before using! 2416 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2417 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2418 * or user (u) memory to probe, and: 2419 * s a string, equivalent to "%s" on direct vsnprintf() use 2420 * 2421 * ** When making changes please also update: 2422 * Documentation/core-api/printk-formats.rst 2423 * 2424 * Note: The default behaviour (unadorned %p) is to hash the address, 2425 * rendering it useful as a unique identifier. 2426 * 2427 * There is also a '%pA' format specifier, but it is only intended to be used 2428 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2429 * See rust/kernel/print.rs for details. 2430 */ 2431 static noinline_for_stack 2432 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2433 struct printf_spec spec) 2434 { 2435 switch (*fmt) { 2436 case 'S': 2437 case 's': 2438 ptr = dereference_symbol_descriptor(ptr); 2439 fallthrough; 2440 case 'B': 2441 return symbol_string(buf, end, ptr, spec, fmt); 2442 case 'R': 2443 case 'r': 2444 return resource_or_range(fmt, buf, end, ptr, spec); 2445 case 'h': 2446 return hex_string(buf, end, ptr, spec, fmt); 2447 case 'b': 2448 switch (fmt[1]) { 2449 case 'l': 2450 return bitmap_list_string(buf, end, ptr, spec, fmt); 2451 default: 2452 return bitmap_string(buf, end, ptr, spec, fmt); 2453 } 2454 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2455 case 'm': /* Contiguous: 000102030405 */ 2456 /* [mM]F (FDDI) */ 2457 /* [mM]R (Reverse order; Bluetooth) */ 2458 return mac_address_string(buf, end, ptr, spec, fmt); 2459 case 'I': /* Formatted IP supported 2460 * 4: 1.2.3.4 2461 * 6: 0001:0203:...:0708 2462 * 6c: 1::708 or 1::1.2.3.4 2463 */ 2464 case 'i': /* Contiguous: 2465 * 4: 001.002.003.004 2466 * 6: 000102...0f 2467 */ 2468 return ip_addr_string(buf, end, ptr, spec, fmt); 2469 case 'E': 2470 return escaped_string(buf, end, ptr, spec, fmt); 2471 case 'U': 2472 return uuid_string(buf, end, ptr, spec, fmt); 2473 case 'V': 2474 return va_format(buf, end, ptr, spec); 2475 case 'K': 2476 return restricted_pointer(buf, end, ptr, spec); 2477 case 'N': 2478 return netdev_bits(buf, end, ptr, spec, fmt); 2479 case '4': 2480 return fourcc_string(buf, end, ptr, spec, fmt); 2481 case 'a': 2482 return address_val(buf, end, ptr, spec, fmt); 2483 case 'd': 2484 return dentry_name(buf, end, ptr, spec, fmt); 2485 case 't': 2486 return time_and_date(buf, end, ptr, spec, fmt); 2487 case 'C': 2488 return clock(buf, end, ptr, spec, fmt); 2489 case 'D': 2490 return file_dentry_name(buf, end, ptr, spec, fmt); 2491 #ifdef CONFIG_BLOCK 2492 case 'g': 2493 return bdev_name(buf, end, ptr, spec, fmt); 2494 #endif 2495 2496 case 'G': 2497 return flags_string(buf, end, ptr, spec, fmt); 2498 case 'O': 2499 return device_node_string(buf, end, ptr, spec, fmt + 1); 2500 case 'f': 2501 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2502 case 'A': 2503 if (!IS_ENABLED(CONFIG_RUST)) { 2504 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2505 return error_string(buf, end, "(%pA?)", spec); 2506 } 2507 return rust_fmt_argument(buf, end, ptr); 2508 case 'x': 2509 return pointer_string(buf, end, ptr, spec); 2510 case 'e': 2511 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2512 if (!IS_ERR(ptr)) 2513 return default_pointer(buf, end, ptr, spec); 2514 return err_ptr(buf, end, ptr, spec); 2515 case 'u': 2516 case 'k': 2517 switch (fmt[1]) { 2518 case 's': 2519 return string(buf, end, ptr, spec); 2520 default: 2521 return error_string(buf, end, "(einval)", spec); 2522 } 2523 default: 2524 return default_pointer(buf, end, ptr, spec); 2525 } 2526 } 2527 2528 struct fmt { 2529 const char *str; 2530 unsigned char state; // enum format_state 2531 unsigned char size; // size of numbers 2532 }; 2533 2534 #define SPEC_CHAR(x, flag) [(x)-32] = flag 2535 static unsigned char spec_flag(unsigned char c) 2536 { 2537 static const unsigned char spec_flag_array[] = { 2538 SPEC_CHAR(' ', SPACE), 2539 SPEC_CHAR('#', SPECIAL), 2540 SPEC_CHAR('+', PLUS), 2541 SPEC_CHAR('-', LEFT), 2542 SPEC_CHAR('0', ZEROPAD), 2543 }; 2544 c -= 32; 2545 return (c < sizeof(spec_flag_array)) ? spec_flag_array[c] : 0; 2546 } 2547 2548 /* 2549 * Helper function to decode printf style format. 2550 * Each call decode a token from the format and return the 2551 * number of characters read (or likely the delta where it wants 2552 * to go on the next call). 2553 * The decoded token is returned through the parameters 2554 * 2555 * 'h', 'l', or 'L' for integer fields 2556 * 'z' support added 23/7/1999 S.H. 2557 * 'z' changed to 'Z' --davidm 1/25/99 2558 * 'Z' changed to 'z' --adobriyan 2017-01-25 2559 * 't' added for ptrdiff_t 2560 * 2561 * @fmt: the format string 2562 * @type of the token returned 2563 * @flags: various flags such as +, -, # tokens.. 2564 * @field_width: overwritten width 2565 * @base: base of the number (octal, hex, ...) 2566 * @precision: precision of a number 2567 * @qualifier: qualifier of a number (long, size_t, ...) 2568 */ 2569 static noinline_for_stack 2570 struct fmt format_decode(struct fmt fmt, struct printf_spec *spec) 2571 { 2572 const char *start = fmt.str; 2573 char flag; 2574 2575 /* we finished early by reading the field width */ 2576 if (unlikely(fmt.state == FORMAT_STATE_WIDTH)) { 2577 if (spec->field_width < 0) { 2578 spec->field_width = -spec->field_width; 2579 spec->flags |= LEFT; 2580 } 2581 fmt.state = FORMAT_STATE_NONE; 2582 goto precision; 2583 } 2584 2585 /* we finished early by reading the precision */ 2586 if (unlikely(fmt.state == FORMAT_STATE_PRECISION)) { 2587 if (spec->precision < 0) 2588 spec->precision = 0; 2589 2590 fmt.state = FORMAT_STATE_NONE; 2591 goto qualifier; 2592 } 2593 2594 /* By default */ 2595 fmt.state = FORMAT_STATE_NONE; 2596 2597 for (; *fmt.str ; fmt.str++) { 2598 if (*fmt.str == '%') 2599 break; 2600 } 2601 2602 /* Return the current non-format string */ 2603 if (fmt.str != start || !*fmt.str) 2604 return fmt; 2605 2606 /* Process flags. This also skips the first '%' */ 2607 spec->flags = 0; 2608 do { 2609 /* this also skips first '%' */ 2610 flag = spec_flag(*++fmt.str); 2611 spec->flags |= flag; 2612 } while (flag); 2613 2614 /* get field width */ 2615 spec->field_width = -1; 2616 2617 if (isdigit(*fmt.str)) 2618 spec->field_width = skip_atoi(&fmt.str); 2619 else if (unlikely(*fmt.str == '*')) { 2620 /* it's the next argument */ 2621 fmt.state = FORMAT_STATE_WIDTH; 2622 fmt.str++; 2623 return fmt; 2624 } 2625 2626 precision: 2627 /* get the precision */ 2628 spec->precision = -1; 2629 if (unlikely(*fmt.str == '.')) { 2630 fmt.str++; 2631 if (isdigit(*fmt.str)) { 2632 spec->precision = skip_atoi(&fmt.str); 2633 if (spec->precision < 0) 2634 spec->precision = 0; 2635 } else if (*fmt.str == '*') { 2636 /* it's the next argument */ 2637 fmt.state = FORMAT_STATE_PRECISION; 2638 fmt.str++; 2639 return fmt; 2640 } 2641 } 2642 2643 qualifier: 2644 /* Set up default numeric format */ 2645 spec->base = 10; 2646 fmt.state = FORMAT_STATE_NUM; 2647 fmt.size = sizeof(int); 2648 static const struct format_state { 2649 unsigned char state; 2650 unsigned char size; 2651 unsigned char flags_or_double_size; 2652 unsigned char base; 2653 } lookup_state[256] = { 2654 // Length 2655 ['l'] = { 0, sizeof(long), sizeof(long long) }, 2656 ['L'] = { 0, sizeof(long long) }, 2657 ['h'] = { 0, sizeof(short), sizeof(char) }, 2658 ['H'] = { 0, sizeof(char) }, // Questionable historical 2659 ['z'] = { 0, sizeof(size_t) }, 2660 ['t'] = { 0, sizeof(ptrdiff_t) }, 2661 2662 // Non-numeric formats 2663 ['c'] = { FORMAT_STATE_CHAR }, 2664 ['s'] = { FORMAT_STATE_STR }, 2665 ['p'] = { FORMAT_STATE_PTR }, 2666 ['%'] = { FORMAT_STATE_PERCENT_CHAR }, 2667 2668 // Numerics 2669 ['o'] = { FORMAT_STATE_NUM, 0, 0, 8 }, 2670 ['x'] = { FORMAT_STATE_NUM, 0, SMALL, 16 }, 2671 ['X'] = { FORMAT_STATE_NUM, 0, 0, 16 }, 2672 ['d'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2673 ['i'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2674 ['u'] = { FORMAT_STATE_NUM, 0, 0, 10, }, 2675 2676 /* 2677 * Since %n poses a greater security risk than 2678 * utility, treat it as any other invalid or 2679 * unsupported format specifier. 2680 */ 2681 }; 2682 2683 const struct format_state *p = lookup_state + (u8)*fmt.str; 2684 if (p->size) { 2685 fmt.size = p->size; 2686 if (p->flags_or_double_size && fmt.str[0] == fmt.str[1]) { 2687 fmt.size = p->flags_or_double_size; 2688 fmt.str++; 2689 } 2690 fmt.str++; 2691 p = lookup_state + *fmt.str; 2692 } 2693 if (p->state) { 2694 if (p->base) 2695 spec->base = p->base; 2696 spec->flags |= p->flags_or_double_size; 2697 fmt.state = p->state; 2698 fmt.str++; 2699 return fmt; 2700 } 2701 2702 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt.str); 2703 fmt.state = FORMAT_STATE_INVALID; 2704 return fmt; 2705 } 2706 2707 static void 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 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 * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate 2727 * as necessary and deal with signedness. 2728 * 2729 * 'size' is the size of the value in bytes. 2730 */ 2731 static unsigned long long convert_num_spec(unsigned int val, int size, struct printf_spec spec) 2732 { 2733 unsigned int shift = 32 - size*8; 2734 2735 val <<= shift; 2736 if (!(spec.flags & SIGN)) 2737 return val >> shift; 2738 return (int)val >> shift; 2739 } 2740 2741 /** 2742 * vsnprintf - Format a string and place it in a buffer 2743 * @buf: The buffer to place the result into 2744 * @size: The size of the buffer, including the trailing null space 2745 * @fmt_str: The format string to use 2746 * @args: Arguments for the format string 2747 * 2748 * This function generally follows C99 vsnprintf, but has some 2749 * extensions and a few limitations: 2750 * 2751 * - ``%n`` is unsupported 2752 * - ``%p*`` is handled by pointer() 2753 * 2754 * See pointer() or Documentation/core-api/printk-formats.rst for more 2755 * extensive description. 2756 * 2757 * **Please update the documentation in both places when making changes** 2758 * 2759 * The return value is the number of characters which would 2760 * be generated for the given input, excluding the trailing 2761 * '\0', as per ISO C99. If you want to have the exact 2762 * number of characters written into @buf as return value 2763 * (not including the trailing '\0'), use vscnprintf(). If the 2764 * return is greater than or equal to @size, the resulting 2765 * string is truncated. 2766 * 2767 * If you're not already dealing with a va_list consider using snprintf(). 2768 */ 2769 int vsnprintf(char *buf, size_t size, const char *fmt_str, va_list args) 2770 { 2771 char *str, *end; 2772 struct printf_spec spec = {0}; 2773 struct fmt fmt = { 2774 .str = fmt_str, 2775 .state = FORMAT_STATE_NONE, 2776 }; 2777 2778 /* Reject out-of-range values early. Large positive sizes are 2779 used for unknown buffer sizes. */ 2780 if (WARN_ON_ONCE(size > INT_MAX)) 2781 return 0; 2782 2783 str = buf; 2784 end = buf + size; 2785 2786 /* Make sure end is always >= buf */ 2787 if (end < buf) { 2788 end = ((void *)-1); 2789 size = end - buf; 2790 } 2791 2792 while (*fmt.str) { 2793 const char *old_fmt = fmt.str; 2794 2795 fmt = format_decode(fmt, &spec); 2796 2797 switch (fmt.state) { 2798 case FORMAT_STATE_NONE: { 2799 int read = fmt.str - old_fmt; 2800 if (str < end) { 2801 int copy = read; 2802 if (copy > end - str) 2803 copy = end - str; 2804 memcpy(str, old_fmt, copy); 2805 } 2806 str += read; 2807 continue; 2808 } 2809 2810 case FORMAT_STATE_NUM: { 2811 unsigned long long num; 2812 if (fmt.size <= sizeof(int)) 2813 num = convert_num_spec(va_arg(args, int), fmt.size, spec); 2814 else 2815 num = va_arg(args, long long); 2816 str = number(str, end, num, spec); 2817 continue; 2818 } 2819 2820 case FORMAT_STATE_WIDTH: 2821 set_field_width(&spec, va_arg(args, int)); 2822 continue; 2823 2824 case FORMAT_STATE_PRECISION: 2825 set_precision(&spec, va_arg(args, int)); 2826 continue; 2827 2828 case FORMAT_STATE_CHAR: { 2829 char c; 2830 2831 if (!(spec.flags & LEFT)) { 2832 while (--spec.field_width > 0) { 2833 if (str < end) 2834 *str = ' '; 2835 ++str; 2836 2837 } 2838 } 2839 c = (unsigned char) va_arg(args, int); 2840 if (str < end) 2841 *str = c; 2842 ++str; 2843 while (--spec.field_width > 0) { 2844 if (str < end) 2845 *str = ' '; 2846 ++str; 2847 } 2848 continue; 2849 } 2850 2851 case FORMAT_STATE_STR: 2852 str = string(str, end, va_arg(args, char *), spec); 2853 continue; 2854 2855 case FORMAT_STATE_PTR: 2856 str = pointer(fmt.str, str, end, va_arg(args, void *), 2857 spec); 2858 while (isalnum(*fmt.str)) 2859 fmt.str++; 2860 continue; 2861 2862 case FORMAT_STATE_PERCENT_CHAR: 2863 if (str < end) 2864 *str = '%'; 2865 ++str; 2866 continue; 2867 2868 default: 2869 /* 2870 * Presumably the arguments passed gcc's type 2871 * checking, but there is no safe or sane way 2872 * for us to continue parsing the format and 2873 * fetching from the va_list; the remaining 2874 * specifiers and arguments would be out of 2875 * sync. 2876 */ 2877 goto out; 2878 } 2879 } 2880 2881 out: 2882 if (size > 0) { 2883 if (str < end) 2884 *str = '\0'; 2885 else 2886 end[-1] = '\0'; 2887 } 2888 2889 /* the trailing null byte doesn't count towards the total */ 2890 return str-buf; 2891 2892 } 2893 EXPORT_SYMBOL(vsnprintf); 2894 2895 /** 2896 * vscnprintf - Format a string and place it in a buffer 2897 * @buf: The buffer to place the result into 2898 * @size: The size of the buffer, including the trailing null space 2899 * @fmt: The format string to use 2900 * @args: Arguments for the format string 2901 * 2902 * The return value is the number of characters which have been written into 2903 * the @buf not including the trailing '\0'. If @size is == 0 the function 2904 * returns 0. 2905 * 2906 * If you're not already dealing with a va_list consider using scnprintf(). 2907 * 2908 * See the vsnprintf() documentation for format string extensions over C99. 2909 */ 2910 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2911 { 2912 int i; 2913 2914 if (unlikely(!size)) 2915 return 0; 2916 2917 i = vsnprintf(buf, size, fmt, args); 2918 2919 if (likely(i < size)) 2920 return i; 2921 2922 return size - 1; 2923 } 2924 EXPORT_SYMBOL(vscnprintf); 2925 2926 /** 2927 * snprintf - Format a string and place it in a buffer 2928 * @buf: The buffer to place the result into 2929 * @size: The size of the buffer, including the trailing null space 2930 * @fmt: The format string to use 2931 * @...: Arguments for the format string 2932 * 2933 * The return value is the number of characters which would be 2934 * generated for the given input, excluding the trailing null, 2935 * as per ISO C99. If the return is greater than or equal to 2936 * @size, the resulting string is truncated. 2937 * 2938 * See the vsnprintf() documentation for format string extensions over C99. 2939 */ 2940 int snprintf(char *buf, size_t size, const char *fmt, ...) 2941 { 2942 va_list args; 2943 int i; 2944 2945 va_start(args, fmt); 2946 i = vsnprintf(buf, size, fmt, args); 2947 va_end(args); 2948 2949 return i; 2950 } 2951 EXPORT_SYMBOL(snprintf); 2952 2953 /** 2954 * scnprintf - Format a string and place it in a buffer 2955 * @buf: The buffer to place the result into 2956 * @size: The size of the buffer, including the trailing null space 2957 * @fmt: The format string to use 2958 * @...: Arguments for the format string 2959 * 2960 * The return value is the number of characters written into @buf not including 2961 * the trailing '\0'. If @size is == 0 the function returns 0. 2962 */ 2963 2964 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2965 { 2966 va_list args; 2967 int i; 2968 2969 va_start(args, fmt); 2970 i = vscnprintf(buf, size, fmt, args); 2971 va_end(args); 2972 2973 return i; 2974 } 2975 EXPORT_SYMBOL(scnprintf); 2976 2977 /** 2978 * vsprintf - Format a string and place it in a buffer 2979 * @buf: The buffer to place the result into 2980 * @fmt: The format string to use 2981 * @args: Arguments for the format string 2982 * 2983 * The function returns the number of characters written 2984 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2985 * buffer overflows. 2986 * 2987 * If you're not already dealing with a va_list consider using sprintf(). 2988 * 2989 * See the vsnprintf() documentation for format string extensions over C99. 2990 */ 2991 int vsprintf(char *buf, const char *fmt, va_list args) 2992 { 2993 return vsnprintf(buf, INT_MAX, fmt, args); 2994 } 2995 EXPORT_SYMBOL(vsprintf); 2996 2997 /** 2998 * sprintf - Format a string and place it in a buffer 2999 * @buf: The buffer to place the result into 3000 * @fmt: The format string to use 3001 * @...: Arguments for the format string 3002 * 3003 * The function returns the number of characters written 3004 * into @buf. Use snprintf() or scnprintf() in order to avoid 3005 * buffer overflows. 3006 * 3007 * See the vsnprintf() documentation for format string extensions over C99. 3008 */ 3009 int sprintf(char *buf, const char *fmt, ...) 3010 { 3011 va_list args; 3012 int i; 3013 3014 va_start(args, fmt); 3015 i = vsnprintf(buf, INT_MAX, fmt, args); 3016 va_end(args); 3017 3018 return i; 3019 } 3020 EXPORT_SYMBOL(sprintf); 3021 3022 #ifdef CONFIG_BINARY_PRINTF 3023 /* 3024 * bprintf service: 3025 * vbin_printf() - VA arguments to binary data 3026 * bstr_printf() - Binary data to text string 3027 */ 3028 3029 /** 3030 * vbin_printf - Parse a format string and place args' binary value in a buffer 3031 * @bin_buf: The buffer to place args' binary value 3032 * @size: The size of the buffer(by words(32bits), not characters) 3033 * @fmt_str: The format string to use 3034 * @args: Arguments for the format string 3035 * 3036 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3037 * is skipped. 3038 * 3039 * The return value is the number of words(32bits) which would be generated for 3040 * the given input. 3041 * 3042 * NOTE: 3043 * If the return value is greater than @size, the resulting bin_buf is NOT 3044 * valid for bstr_printf(). 3045 */ 3046 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt_str, va_list args) 3047 { 3048 struct fmt fmt = { 3049 .str = fmt_str, 3050 .state = FORMAT_STATE_NONE, 3051 }; 3052 struct printf_spec spec = {0}; 3053 char *str, *end; 3054 int width; 3055 3056 str = (char *)bin_buf; 3057 end = (char *)(bin_buf + size); 3058 3059 #define save_arg(type) \ 3060 ({ \ 3061 unsigned long long value; \ 3062 if (sizeof(type) == 8) { \ 3063 unsigned long long val8; \ 3064 str = PTR_ALIGN(str, sizeof(u32)); \ 3065 val8 = va_arg(args, unsigned long long); \ 3066 if (str + sizeof(type) <= end) { \ 3067 *(u32 *)str = *(u32 *)&val8; \ 3068 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3069 } \ 3070 value = val8; \ 3071 } else { \ 3072 unsigned int val4; \ 3073 str = PTR_ALIGN(str, sizeof(type)); \ 3074 val4 = va_arg(args, int); \ 3075 if (str + sizeof(type) <= end) \ 3076 *(typeof(type) *)str = (type)(long)val4; \ 3077 value = (unsigned long long)val4; \ 3078 } \ 3079 str += sizeof(type); \ 3080 value; \ 3081 }) 3082 3083 while (*fmt.str) { 3084 fmt = format_decode(fmt, &spec); 3085 3086 switch (fmt.state) { 3087 case FORMAT_STATE_NONE: 3088 case FORMAT_STATE_PERCENT_CHAR: 3089 break; 3090 case FORMAT_STATE_INVALID: 3091 goto out; 3092 3093 case FORMAT_STATE_WIDTH: 3094 case FORMAT_STATE_PRECISION: 3095 width = (int)save_arg(int); 3096 /* Pointers may require the width */ 3097 if (*fmt.str == 'p') 3098 set_field_width(&spec, width); 3099 break; 3100 3101 case FORMAT_STATE_CHAR: 3102 save_arg(char); 3103 break; 3104 3105 case FORMAT_STATE_STR: { 3106 const char *save_str = va_arg(args, char *); 3107 const char *err_msg; 3108 size_t len; 3109 3110 err_msg = check_pointer_msg(save_str); 3111 if (err_msg) 3112 save_str = err_msg; 3113 3114 len = strlen(save_str) + 1; 3115 if (str + len < end) 3116 memcpy(str, save_str, len); 3117 str += len; 3118 break; 3119 } 3120 3121 case FORMAT_STATE_PTR: 3122 /* Dereferenced pointers must be done now */ 3123 switch (*fmt.str) { 3124 /* Dereference of functions is still OK */ 3125 case 'S': 3126 case 's': 3127 case 'x': 3128 case 'K': 3129 case 'e': 3130 save_arg(void *); 3131 break; 3132 default: 3133 if (!isalnum(*fmt.str)) { 3134 save_arg(void *); 3135 break; 3136 } 3137 str = pointer(fmt.str, str, end, va_arg(args, void *), 3138 spec); 3139 if (str + 1 < end) 3140 *str++ = '\0'; 3141 else 3142 end[-1] = '\0'; /* Must be nul terminated */ 3143 } 3144 /* skip all alphanumeric pointer suffixes */ 3145 while (isalnum(*fmt.str)) 3146 fmt.str++; 3147 break; 3148 3149 case FORMAT_STATE_NUM: 3150 if (fmt.size > sizeof(int)) { 3151 save_arg(long long); 3152 } else { 3153 save_arg(int); 3154 } 3155 } 3156 } 3157 3158 out: 3159 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3160 #undef save_arg 3161 } 3162 EXPORT_SYMBOL_GPL(vbin_printf); 3163 3164 /** 3165 * bstr_printf - Format a string from binary arguments and place it in a buffer 3166 * @buf: The buffer to place the result into 3167 * @size: The size of the buffer, including the trailing null space 3168 * @fmt_str: The format string to use 3169 * @bin_buf: Binary arguments for the format string 3170 * 3171 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3172 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3173 * a binary buffer that generated by vbin_printf. 3174 * 3175 * The format follows C99 vsnprintf, but has some extensions: 3176 * see vsnprintf comment for details. 3177 * 3178 * The return value is the number of characters which would 3179 * be generated for the given input, excluding the trailing 3180 * '\0', as per ISO C99. If you want to have the exact 3181 * number of characters written into @buf as return value 3182 * (not including the trailing '\0'), use vscnprintf(). If the 3183 * return is greater than or equal to @size, the resulting 3184 * string is truncated. 3185 */ 3186 int bstr_printf(char *buf, size_t size, const char *fmt_str, const u32 *bin_buf) 3187 { 3188 struct fmt fmt = { 3189 .str = fmt_str, 3190 .state = FORMAT_STATE_NONE, 3191 }; 3192 struct printf_spec spec = {0}; 3193 char *str, *end; 3194 const char *args = (const char *)bin_buf; 3195 3196 if (WARN_ON_ONCE(size > INT_MAX)) 3197 return 0; 3198 3199 str = buf; 3200 end = buf + size; 3201 3202 #define get_arg(type) \ 3203 ({ \ 3204 typeof(type) value; \ 3205 if (sizeof(type) == 8) { \ 3206 args = PTR_ALIGN(args, sizeof(u32)); \ 3207 *(u32 *)&value = *(u32 *)args; \ 3208 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3209 } else { \ 3210 args = PTR_ALIGN(args, sizeof(type)); \ 3211 value = *(typeof(type) *)args; \ 3212 } \ 3213 args += sizeof(type); \ 3214 value; \ 3215 }) 3216 3217 /* Make sure end is always >= buf */ 3218 if (end < buf) { 3219 end = ((void *)-1); 3220 size = end - buf; 3221 } 3222 3223 while (*fmt.str) { 3224 const char *old_fmt = fmt.str; 3225 unsigned long long num; 3226 3227 fmt = format_decode(fmt, &spec); 3228 switch (fmt.state) { 3229 case FORMAT_STATE_NONE: { 3230 int read = fmt.str - old_fmt; 3231 if (str < end) { 3232 int copy = read; 3233 if (copy > end - str) 3234 copy = end - str; 3235 memcpy(str, old_fmt, copy); 3236 } 3237 str += read; 3238 continue; 3239 } 3240 3241 case FORMAT_STATE_WIDTH: 3242 set_field_width(&spec, get_arg(int)); 3243 continue; 3244 3245 case FORMAT_STATE_PRECISION: 3246 set_precision(&spec, get_arg(int)); 3247 continue; 3248 3249 case FORMAT_STATE_CHAR: { 3250 char c; 3251 3252 if (!(spec.flags & LEFT)) { 3253 while (--spec.field_width > 0) { 3254 if (str < end) 3255 *str = ' '; 3256 ++str; 3257 } 3258 } 3259 c = (unsigned char) get_arg(char); 3260 if (str < end) 3261 *str = c; 3262 ++str; 3263 while (--spec.field_width > 0) { 3264 if (str < end) 3265 *str = ' '; 3266 ++str; 3267 } 3268 continue; 3269 } 3270 3271 case FORMAT_STATE_STR: { 3272 const char *str_arg = args; 3273 args += strlen(str_arg) + 1; 3274 str = string(str, end, (char *)str_arg, spec); 3275 continue; 3276 } 3277 3278 case FORMAT_STATE_PTR: { 3279 bool process = false; 3280 int copy, len; 3281 /* Non function dereferences were already done */ 3282 switch (*fmt.str) { 3283 case 'S': 3284 case 's': 3285 case 'x': 3286 case 'K': 3287 case 'e': 3288 process = true; 3289 break; 3290 default: 3291 if (!isalnum(*fmt.str)) { 3292 process = true; 3293 break; 3294 } 3295 /* Pointer dereference was already processed */ 3296 if (str < end) { 3297 len = copy = strlen(args); 3298 if (copy > end - str) 3299 copy = end - str; 3300 memcpy(str, args, copy); 3301 str += len; 3302 args += len + 1; 3303 } 3304 } 3305 if (process) 3306 str = pointer(fmt.str, str, end, get_arg(void *), spec); 3307 3308 while (isalnum(*fmt.str)) 3309 fmt.str++; 3310 continue; 3311 } 3312 3313 case FORMAT_STATE_PERCENT_CHAR: 3314 if (str < end) 3315 *str = '%'; 3316 ++str; 3317 continue; 3318 3319 case FORMAT_STATE_INVALID: 3320 goto out; 3321 3322 case FORMAT_STATE_NUM: 3323 if (fmt.size > sizeof(int)) { 3324 num = get_arg(long long); 3325 } else { 3326 num = convert_num_spec(get_arg(int), fmt.size, spec); 3327 } 3328 str = number(str, end, num, spec); 3329 continue; 3330 } 3331 } /* while(*fmt.str) */ 3332 3333 out: 3334 if (size > 0) { 3335 if (str < end) 3336 *str = '\0'; 3337 else 3338 end[-1] = '\0'; 3339 } 3340 3341 #undef get_arg 3342 3343 /* the trailing null byte doesn't count towards the total */ 3344 return str - buf; 3345 } 3346 EXPORT_SYMBOL_GPL(bstr_printf); 3347 3348 #endif /* CONFIG_BINARY_PRINTF */ 3349 3350 /** 3351 * vsscanf - Unformat a buffer into a list of arguments 3352 * @buf: input buffer 3353 * @fmt: format of buffer 3354 * @args: arguments 3355 */ 3356 int vsscanf(const char *buf, const char *fmt, va_list args) 3357 { 3358 const char *str = buf; 3359 char *next; 3360 char digit; 3361 int num = 0; 3362 u8 qualifier; 3363 unsigned int base; 3364 union { 3365 long long s; 3366 unsigned long long u; 3367 } val; 3368 s16 field_width; 3369 bool is_sign; 3370 3371 while (*fmt) { 3372 /* skip any white space in format */ 3373 /* white space in format matches any amount of 3374 * white space, including none, in the input. 3375 */ 3376 if (isspace(*fmt)) { 3377 fmt = skip_spaces(++fmt); 3378 str = skip_spaces(str); 3379 } 3380 3381 /* anything that is not a conversion must match exactly */ 3382 if (*fmt != '%' && *fmt) { 3383 if (*fmt++ != *str++) 3384 break; 3385 continue; 3386 } 3387 3388 if (!*fmt) 3389 break; 3390 ++fmt; 3391 3392 /* skip this conversion. 3393 * advance both strings to next white space 3394 */ 3395 if (*fmt == '*') { 3396 if (!*str) 3397 break; 3398 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3399 /* '%*[' not yet supported, invalid format */ 3400 if (*fmt == '[') 3401 return num; 3402 fmt++; 3403 } 3404 while (!isspace(*str) && *str) 3405 str++; 3406 continue; 3407 } 3408 3409 /* get field width */ 3410 field_width = -1; 3411 if (isdigit(*fmt)) { 3412 field_width = skip_atoi(&fmt); 3413 if (field_width <= 0) 3414 break; 3415 } 3416 3417 /* get conversion qualifier */ 3418 qualifier = -1; 3419 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3420 *fmt == 'z') { 3421 qualifier = *fmt++; 3422 if (unlikely(qualifier == *fmt)) { 3423 if (qualifier == 'h') { 3424 qualifier = 'H'; 3425 fmt++; 3426 } else if (qualifier == 'l') { 3427 qualifier = 'L'; 3428 fmt++; 3429 } 3430 } 3431 } 3432 3433 if (!*fmt) 3434 break; 3435 3436 if (*fmt == 'n') { 3437 /* return number of characters read so far */ 3438 *va_arg(args, int *) = str - buf; 3439 ++fmt; 3440 continue; 3441 } 3442 3443 if (!*str) 3444 break; 3445 3446 base = 10; 3447 is_sign = false; 3448 3449 switch (*fmt++) { 3450 case 'c': 3451 { 3452 char *s = (char *)va_arg(args, char*); 3453 if (field_width == -1) 3454 field_width = 1; 3455 do { 3456 *s++ = *str++; 3457 } while (--field_width > 0 && *str); 3458 num++; 3459 } 3460 continue; 3461 case 's': 3462 { 3463 char *s = (char *)va_arg(args, char *); 3464 if (field_width == -1) 3465 field_width = SHRT_MAX; 3466 /* first, skip leading white space in buffer */ 3467 str = skip_spaces(str); 3468 3469 /* now copy until next white space */ 3470 while (*str && !isspace(*str) && field_width--) 3471 *s++ = *str++; 3472 *s = '\0'; 3473 num++; 3474 } 3475 continue; 3476 /* 3477 * Warning: This implementation of the '[' conversion specifier 3478 * deviates from its glibc counterpart in the following ways: 3479 * (1) It does NOT support ranges i.e. '-' is NOT a special 3480 * character 3481 * (2) It cannot match the closing bracket ']' itself 3482 * (3) A field width is required 3483 * (4) '%*[' (discard matching input) is currently not supported 3484 * 3485 * Example usage: 3486 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3487 * buf1, buf2, buf3); 3488 * if (ret < 3) 3489 * // etc.. 3490 */ 3491 case '[': 3492 { 3493 char *s = (char *)va_arg(args, char *); 3494 DECLARE_BITMAP(set, 256) = {0}; 3495 unsigned int len = 0; 3496 bool negate = (*fmt == '^'); 3497 3498 /* field width is required */ 3499 if (field_width == -1) 3500 return num; 3501 3502 if (negate) 3503 ++fmt; 3504 3505 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3506 __set_bit((u8)*fmt, set); 3507 3508 /* no ']' or no character set found */ 3509 if (!*fmt || !len) 3510 return num; 3511 ++fmt; 3512 3513 if (negate) { 3514 bitmap_complement(set, set, 256); 3515 /* exclude null '\0' byte */ 3516 __clear_bit(0, set); 3517 } 3518 3519 /* match must be non-empty */ 3520 if (!test_bit((u8)*str, set)) 3521 return num; 3522 3523 while (test_bit((u8)*str, set) && field_width--) 3524 *s++ = *str++; 3525 *s = '\0'; 3526 ++num; 3527 } 3528 continue; 3529 case 'o': 3530 base = 8; 3531 break; 3532 case 'x': 3533 case 'X': 3534 base = 16; 3535 break; 3536 case 'i': 3537 base = 0; 3538 fallthrough; 3539 case 'd': 3540 is_sign = true; 3541 fallthrough; 3542 case 'u': 3543 break; 3544 case '%': 3545 /* looking for '%' in str */ 3546 if (*str++ != '%') 3547 return num; 3548 continue; 3549 default: 3550 /* invalid format; stop here */ 3551 return num; 3552 } 3553 3554 /* have some sort of integer conversion. 3555 * first, skip white space in buffer. 3556 */ 3557 str = skip_spaces(str); 3558 3559 digit = *str; 3560 if (is_sign && digit == '-') { 3561 if (field_width == 1) 3562 break; 3563 3564 digit = *(str + 1); 3565 } 3566 3567 if (!digit 3568 || (base == 16 && !isxdigit(digit)) 3569 || (base == 10 && !isdigit(digit)) 3570 || (base == 8 && !isodigit(digit)) 3571 || (base == 0 && !isdigit(digit))) 3572 break; 3573 3574 if (is_sign) 3575 val.s = simple_strntoll(str, &next, base, 3576 field_width >= 0 ? field_width : INT_MAX); 3577 else 3578 val.u = simple_strntoull(str, &next, base, 3579 field_width >= 0 ? field_width : INT_MAX); 3580 3581 switch (qualifier) { 3582 case 'H': /* that's 'hh' in format */ 3583 if (is_sign) 3584 *va_arg(args, signed char *) = val.s; 3585 else 3586 *va_arg(args, unsigned char *) = val.u; 3587 break; 3588 case 'h': 3589 if (is_sign) 3590 *va_arg(args, short *) = val.s; 3591 else 3592 *va_arg(args, unsigned short *) = val.u; 3593 break; 3594 case 'l': 3595 if (is_sign) 3596 *va_arg(args, long *) = val.s; 3597 else 3598 *va_arg(args, unsigned long *) = val.u; 3599 break; 3600 case 'L': 3601 if (is_sign) 3602 *va_arg(args, long long *) = val.s; 3603 else 3604 *va_arg(args, unsigned long long *) = val.u; 3605 break; 3606 case 'z': 3607 *va_arg(args, size_t *) = val.u; 3608 break; 3609 default: 3610 if (is_sign) 3611 *va_arg(args, int *) = val.s; 3612 else 3613 *va_arg(args, unsigned int *) = val.u; 3614 break; 3615 } 3616 num++; 3617 3618 if (!next) 3619 break; 3620 str = next; 3621 } 3622 3623 return num; 3624 } 3625 EXPORT_SYMBOL(vsscanf); 3626 3627 /** 3628 * sscanf - Unformat a buffer into a list of arguments 3629 * @buf: input buffer 3630 * @fmt: formatting of buffer 3631 * @...: resulting arguments 3632 */ 3633 int sscanf(const char *buf, const char *fmt, ...) 3634 { 3635 va_list args; 3636 int i; 3637 3638 va_start(args, fmt); 3639 i = vsscanf(buf, fmt, args); 3640 va_end(args); 3641 3642 return i; 3643 } 3644 EXPORT_SYMBOL(sscanf); 3645