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 #ifdef CONFIG_COMMON_CLK 1985 return string(buf, end, __clk_get_name(clk), spec); 1986 #else 1987 return ptr_to_id(buf, end, clk, spec); 1988 #endif 1989 } 1990 1991 static 1992 char *format_flags(char *buf, char *end, unsigned long flags, 1993 const struct trace_print_flags *names) 1994 { 1995 unsigned long mask; 1996 1997 for ( ; flags && names->name; names++) { 1998 mask = names->mask; 1999 if ((flags & mask) != mask) 2000 continue; 2001 2002 buf = string(buf, end, names->name, default_str_spec); 2003 2004 flags &= ~mask; 2005 if (flags) { 2006 if (buf < end) 2007 *buf = '|'; 2008 buf++; 2009 } 2010 } 2011 2012 if (flags) 2013 buf = number(buf, end, flags, default_flag_spec); 2014 2015 return buf; 2016 } 2017 2018 struct page_flags_fields { 2019 int width; 2020 int shift; 2021 int mask; 2022 const struct printf_spec *spec; 2023 const char *name; 2024 }; 2025 2026 static const struct page_flags_fields pff[] = { 2027 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 2028 &default_dec_spec, "section"}, 2029 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2030 &default_dec_spec, "node"}, 2031 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2032 &default_dec_spec, "zone"}, 2033 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2034 &default_flag_spec, "lastcpupid"}, 2035 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2036 &default_flag_spec, "kasantag"}, 2037 }; 2038 2039 static 2040 char *format_page_flags(char *buf, char *end, unsigned long flags) 2041 { 2042 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2043 bool append = false; 2044 int i; 2045 2046 buf = number(buf, end, flags, default_flag_spec); 2047 if (buf < end) 2048 *buf = '('; 2049 buf++; 2050 2051 /* Page flags from the main area. */ 2052 if (main_flags) { 2053 buf = format_flags(buf, end, main_flags, pageflag_names); 2054 append = true; 2055 } 2056 2057 /* Page flags from the fields area */ 2058 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2059 /* Skip undefined fields. */ 2060 if (!pff[i].width) 2061 continue; 2062 2063 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2064 if (append) { 2065 if (buf < end) 2066 *buf = '|'; 2067 buf++; 2068 } 2069 2070 buf = string(buf, end, pff[i].name, default_str_spec); 2071 if (buf < end) 2072 *buf = '='; 2073 buf++; 2074 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2075 *pff[i].spec); 2076 2077 append = true; 2078 } 2079 if (buf < end) 2080 *buf = ')'; 2081 buf++; 2082 2083 return buf; 2084 } 2085 2086 static noinline_for_stack 2087 char *flags_string(char *buf, char *end, void *flags_ptr, 2088 struct printf_spec spec, const char *fmt) 2089 { 2090 unsigned long flags; 2091 const struct trace_print_flags *names; 2092 2093 if (check_pointer(&buf, end, flags_ptr, spec)) 2094 return buf; 2095 2096 switch (fmt[1]) { 2097 case 'p': 2098 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2099 case 'v': 2100 flags = *(unsigned long *)flags_ptr; 2101 names = vmaflag_names; 2102 break; 2103 case 'g': 2104 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2105 names = gfpflag_names; 2106 break; 2107 default: 2108 return error_string(buf, end, "(%pG?)", spec); 2109 } 2110 2111 return format_flags(buf, end, flags, names); 2112 } 2113 2114 static noinline_for_stack 2115 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2116 char *end) 2117 { 2118 int depth; 2119 2120 /* Loop starting from the root node to the current node. */ 2121 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2122 /* 2123 * Only get a reference for other nodes (i.e. parent nodes). 2124 * fwnode refcount may be 0 here. 2125 */ 2126 struct fwnode_handle *__fwnode = depth ? 2127 fwnode_get_nth_parent(fwnode, depth) : fwnode; 2128 2129 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2130 default_str_spec); 2131 buf = string(buf, end, fwnode_get_name(__fwnode), 2132 default_str_spec); 2133 2134 if (depth) 2135 fwnode_handle_put(__fwnode); 2136 } 2137 2138 return buf; 2139 } 2140 2141 static noinline_for_stack 2142 char *device_node_string(char *buf, char *end, struct device_node *dn, 2143 struct printf_spec spec, const char *fmt) 2144 { 2145 char tbuf[sizeof("xxxx") + 1]; 2146 const char *p; 2147 int ret; 2148 char *buf_start = buf; 2149 struct property *prop; 2150 bool has_mult, pass; 2151 2152 struct printf_spec str_spec = spec; 2153 str_spec.field_width = -1; 2154 2155 if (fmt[0] != 'F') 2156 return error_string(buf, end, "(%pO?)", spec); 2157 2158 if (!IS_ENABLED(CONFIG_OF)) 2159 return error_string(buf, end, "(%pOF?)", spec); 2160 2161 if (check_pointer(&buf, end, dn, spec)) 2162 return buf; 2163 2164 /* simple case without anything any more format specifiers */ 2165 fmt++; 2166 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2167 fmt = "f"; 2168 2169 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2170 int precision; 2171 if (pass) { 2172 if (buf < end) 2173 *buf = ':'; 2174 buf++; 2175 } 2176 2177 switch (*fmt) { 2178 case 'f': /* full_name */ 2179 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2180 end); 2181 break; 2182 case 'n': /* name */ 2183 p = fwnode_get_name(of_fwnode_handle(dn)); 2184 precision = str_spec.precision; 2185 str_spec.precision = strchrnul(p, '@') - p; 2186 buf = string(buf, end, p, str_spec); 2187 str_spec.precision = precision; 2188 break; 2189 case 'p': /* phandle */ 2190 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2191 break; 2192 case 'P': /* path-spec */ 2193 p = fwnode_get_name(of_fwnode_handle(dn)); 2194 if (!p[1]) 2195 p = "/"; 2196 buf = string(buf, end, p, str_spec); 2197 break; 2198 case 'F': /* flags */ 2199 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2200 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2201 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2202 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2203 tbuf[4] = 0; 2204 buf = string_nocheck(buf, end, tbuf, str_spec); 2205 break; 2206 case 'c': /* major compatible string */ 2207 ret = of_property_read_string(dn, "compatible", &p); 2208 if (!ret) 2209 buf = string(buf, end, p, str_spec); 2210 break; 2211 case 'C': /* full compatible string */ 2212 has_mult = false; 2213 of_property_for_each_string(dn, "compatible", prop, p) { 2214 if (has_mult) 2215 buf = string_nocheck(buf, end, ",", str_spec); 2216 buf = string_nocheck(buf, end, "\"", str_spec); 2217 buf = string(buf, end, p, str_spec); 2218 buf = string_nocheck(buf, end, "\"", str_spec); 2219 2220 has_mult = true; 2221 } 2222 break; 2223 default: 2224 break; 2225 } 2226 } 2227 2228 return widen_string(buf, buf - buf_start, end, spec); 2229 } 2230 2231 static noinline_for_stack 2232 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2233 struct printf_spec spec, const char *fmt) 2234 { 2235 struct printf_spec str_spec = spec; 2236 char *buf_start = buf; 2237 2238 str_spec.field_width = -1; 2239 2240 if (*fmt != 'w') 2241 return error_string(buf, end, "(%pf?)", spec); 2242 2243 if (check_pointer(&buf, end, fwnode, spec)) 2244 return buf; 2245 2246 fmt++; 2247 2248 switch (*fmt) { 2249 case 'P': /* name */ 2250 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2251 break; 2252 case 'f': /* full_name */ 2253 default: 2254 buf = fwnode_full_name_string(fwnode, buf, end); 2255 break; 2256 } 2257 2258 return widen_string(buf, buf - buf_start, end, spec); 2259 } 2260 2261 static noinline_for_stack 2262 char *resource_or_range(const char *fmt, char *buf, char *end, void *ptr, 2263 struct printf_spec spec) 2264 { 2265 if (*fmt == 'r' && fmt[1] == 'a') 2266 return range_string(buf, end, ptr, spec, fmt); 2267 return resource_string(buf, end, ptr, spec, fmt); 2268 } 2269 2270 int __init no_hash_pointers_enable(char *str) 2271 { 2272 if (no_hash_pointers) 2273 return 0; 2274 2275 no_hash_pointers = true; 2276 2277 pr_warn("**********************************************************\n"); 2278 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2279 pr_warn("** **\n"); 2280 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2281 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2282 pr_warn("** might reduce the security of your system. **\n"); 2283 pr_warn("** **\n"); 2284 pr_warn("** If you see this message and you are not debugging **\n"); 2285 pr_warn("** the kernel, report this immediately to your system **\n"); 2286 pr_warn("** administrator! **\n"); 2287 pr_warn("** **\n"); 2288 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2289 pr_warn("**********************************************************\n"); 2290 2291 return 0; 2292 } 2293 early_param("no_hash_pointers", no_hash_pointers_enable); 2294 2295 /* 2296 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2297 * by an extra set of alphanumeric characters that are extended format 2298 * specifiers. 2299 * 2300 * Please update scripts/checkpatch.pl when adding/removing conversion 2301 * characters. (Search for "check for vsprintf extension"). 2302 * 2303 * Right now we handle: 2304 * 2305 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2306 * - 's' For symbolic direct pointers (or function descriptors) without offset 2307 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2308 * - 'S[R]b' as above with module build ID (for use in backtraces) 2309 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2310 * %ps and %pS. Be careful when re-using these specifiers. 2311 * - 'B' For backtraced symbolic direct pointers with offset 2312 * - 'Bb' as above with module build ID (for use in backtraces) 2313 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2314 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2315 * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] 2316 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2317 * width which must be explicitly specified either as part of the 2318 * format string '%32b[l]' or through '%*b[l]', [l] selects 2319 * range-list format instead of hex format 2320 * - 'M' For a 6-byte MAC address, it prints the address in the 2321 * usual colon-separated hex notation 2322 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2323 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2324 * with a dash-separated hex notation 2325 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2326 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2327 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2328 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2329 * [S][pfs] 2330 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2331 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2332 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2333 * IPv6 omits the colons (01020304...0f) 2334 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2335 * [S][pfs] 2336 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2337 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2338 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2339 * - 'I[6S]c' for IPv6 addresses printed as specified by 2340 * https://tools.ietf.org/html/rfc5952 2341 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2342 * of the following flags (see string_escape_mem() for the 2343 * details): 2344 * a - ESCAPE_ANY 2345 * c - ESCAPE_SPECIAL 2346 * h - ESCAPE_HEX 2347 * n - ESCAPE_NULL 2348 * o - ESCAPE_OCTAL 2349 * p - ESCAPE_NP 2350 * s - ESCAPE_SPACE 2351 * By default ESCAPE_ANY_NP is used. 2352 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2353 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2354 * Options for %pU are: 2355 * b big endian lower case hex (default) 2356 * B big endian UPPER case hex 2357 * l little endian lower case hex 2358 * L little endian UPPER case hex 2359 * big endian output byte order is: 2360 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2361 * little endian output byte order is: 2362 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2363 * - 'V' For a struct va_format which contains a format string * and va_list *, 2364 * call vsnprintf(->format, *->va_list). 2365 * Implements a "recursive vsnprintf". 2366 * Do not use this feature without some mechanism to verify the 2367 * correctness of the format string and va_list arguments. 2368 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2369 * Use only for procfs, sysfs and similar files, not printk(); please 2370 * read the documentation (path below) first. 2371 * - 'NF' For a netdev_features_t 2372 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2373 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2374 * a certain separator (' ' by default): 2375 * C colon 2376 * D dash 2377 * N no separator 2378 * The maximum supported length is 64 bytes of the input. Consider 2379 * to use print_hex_dump() for the larger input. 2380 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2381 * (default assumed to be phys_addr_t, passed by reference) 2382 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2383 * - 'D[234]' Same as 'd' but for a struct file 2384 * - 'g' For block_device name (gendisk + partition number) 2385 * - 't[RT][dt][r][s]' For time and date as represented by: 2386 * R struct rtc_time 2387 * T time64_t 2388 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2389 * (legacy clock framework) of the clock 2390 * - 'G' For flags to be printed as a collection of symbolic strings that would 2391 * construct the specific value. Supported flags given by option: 2392 * p page flags (see struct page) given as pointer to unsigned long 2393 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2394 * v vma flags (VM_*) given as pointer to unsigned long 2395 * - 'OF[fnpPcCF]' For a device tree object 2396 * Without any optional arguments prints the full_name 2397 * f device node full_name 2398 * n device node name 2399 * p device node phandle 2400 * P device node path spec (name + @unit) 2401 * F device node flags 2402 * c major compatible string 2403 * C full compatible string 2404 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2405 * Without an option prints the full name of the node 2406 * f full name 2407 * P node name, including a possible unit address 2408 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2409 * Please read the documentation (path below) before using! 2410 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2411 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2412 * or user (u) memory to probe, and: 2413 * s a string, equivalent to "%s" on direct vsnprintf() use 2414 * 2415 * ** When making changes please also update: 2416 * Documentation/core-api/printk-formats.rst 2417 * 2418 * Note: The default behaviour (unadorned %p) is to hash the address, 2419 * rendering it useful as a unique identifier. 2420 * 2421 * There is also a '%pA' format specifier, but it is only intended to be used 2422 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2423 * See rust/kernel/print.rs for details. 2424 */ 2425 static noinline_for_stack 2426 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2427 struct printf_spec spec) 2428 { 2429 switch (*fmt) { 2430 case 'S': 2431 case 's': 2432 ptr = dereference_symbol_descriptor(ptr); 2433 fallthrough; 2434 case 'B': 2435 return symbol_string(buf, end, ptr, spec, fmt); 2436 case 'R': 2437 case 'r': 2438 return resource_or_range(fmt, buf, end, ptr, spec); 2439 case 'h': 2440 return hex_string(buf, end, ptr, spec, fmt); 2441 case 'b': 2442 switch (fmt[1]) { 2443 case 'l': 2444 return bitmap_list_string(buf, end, ptr, spec, fmt); 2445 default: 2446 return bitmap_string(buf, end, ptr, spec, fmt); 2447 } 2448 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2449 case 'm': /* Contiguous: 000102030405 */ 2450 /* [mM]F (FDDI) */ 2451 /* [mM]R (Reverse order; Bluetooth) */ 2452 return mac_address_string(buf, end, ptr, spec, fmt); 2453 case 'I': /* Formatted IP supported 2454 * 4: 1.2.3.4 2455 * 6: 0001:0203:...:0708 2456 * 6c: 1::708 or 1::1.2.3.4 2457 */ 2458 case 'i': /* Contiguous: 2459 * 4: 001.002.003.004 2460 * 6: 000102...0f 2461 */ 2462 return ip_addr_string(buf, end, ptr, spec, fmt); 2463 case 'E': 2464 return escaped_string(buf, end, ptr, spec, fmt); 2465 case 'U': 2466 return uuid_string(buf, end, ptr, spec, fmt); 2467 case 'V': 2468 return va_format(buf, end, ptr, spec); 2469 case 'K': 2470 return restricted_pointer(buf, end, ptr, spec); 2471 case 'N': 2472 return netdev_bits(buf, end, ptr, spec, fmt); 2473 case '4': 2474 return fourcc_string(buf, end, ptr, spec, fmt); 2475 case 'a': 2476 return address_val(buf, end, ptr, spec, fmt); 2477 case 'd': 2478 return dentry_name(buf, end, ptr, spec, fmt); 2479 case 't': 2480 return time_and_date(buf, end, ptr, spec, fmt); 2481 case 'C': 2482 return clock(buf, end, ptr, spec, fmt); 2483 case 'D': 2484 return file_dentry_name(buf, end, ptr, spec, fmt); 2485 #ifdef CONFIG_BLOCK 2486 case 'g': 2487 return bdev_name(buf, end, ptr, spec, fmt); 2488 #endif 2489 2490 case 'G': 2491 return flags_string(buf, end, ptr, spec, fmt); 2492 case 'O': 2493 return device_node_string(buf, end, ptr, spec, fmt + 1); 2494 case 'f': 2495 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2496 case 'A': 2497 if (!IS_ENABLED(CONFIG_RUST)) { 2498 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2499 return error_string(buf, end, "(%pA?)", spec); 2500 } 2501 return rust_fmt_argument(buf, end, ptr); 2502 case 'x': 2503 return pointer_string(buf, end, ptr, spec); 2504 case 'e': 2505 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2506 if (!IS_ERR(ptr)) 2507 return default_pointer(buf, end, ptr, spec); 2508 return err_ptr(buf, end, ptr, spec); 2509 case 'u': 2510 case 'k': 2511 switch (fmt[1]) { 2512 case 's': 2513 return string(buf, end, ptr, spec); 2514 default: 2515 return error_string(buf, end, "(einval)", spec); 2516 } 2517 default: 2518 return default_pointer(buf, end, ptr, spec); 2519 } 2520 } 2521 2522 struct fmt { 2523 const char *str; 2524 unsigned char state; // enum format_state 2525 unsigned char size; // size of numbers 2526 }; 2527 2528 #define SPEC_CHAR(x, flag) [(x)-32] = flag 2529 static unsigned char spec_flag(unsigned char c) 2530 { 2531 static const unsigned char spec_flag_array[] = { 2532 SPEC_CHAR(' ', SPACE), 2533 SPEC_CHAR('#', SPECIAL), 2534 SPEC_CHAR('+', PLUS), 2535 SPEC_CHAR('-', LEFT), 2536 SPEC_CHAR('0', ZEROPAD), 2537 }; 2538 c -= 32; 2539 return (c < sizeof(spec_flag_array)) ? spec_flag_array[c] : 0; 2540 } 2541 2542 /* 2543 * Helper function to decode printf style format. 2544 * Each call decode a token from the format and return the 2545 * number of characters read (or likely the delta where it wants 2546 * to go on the next call). 2547 * The decoded token is returned through the parameters 2548 * 2549 * 'h', 'l', or 'L' for integer fields 2550 * 'z' support added 23/7/1999 S.H. 2551 * 'z' changed to 'Z' --davidm 1/25/99 2552 * 'Z' changed to 'z' --adobriyan 2017-01-25 2553 * 't' added for ptrdiff_t 2554 * 2555 * @fmt: the format string 2556 * @type of the token returned 2557 * @flags: various flags such as +, -, # tokens.. 2558 * @field_width: overwritten width 2559 * @base: base of the number (octal, hex, ...) 2560 * @precision: precision of a number 2561 * @qualifier: qualifier of a number (long, size_t, ...) 2562 */ 2563 static noinline_for_stack 2564 struct fmt format_decode(struct fmt fmt, struct printf_spec *spec) 2565 { 2566 const char *start = fmt.str; 2567 char flag; 2568 2569 /* we finished early by reading the field width */ 2570 if (unlikely(fmt.state == FORMAT_STATE_WIDTH)) { 2571 if (spec->field_width < 0) { 2572 spec->field_width = -spec->field_width; 2573 spec->flags |= LEFT; 2574 } 2575 fmt.state = FORMAT_STATE_NONE; 2576 goto precision; 2577 } 2578 2579 /* we finished early by reading the precision */ 2580 if (unlikely(fmt.state == FORMAT_STATE_PRECISION)) { 2581 if (spec->precision < 0) 2582 spec->precision = 0; 2583 2584 fmt.state = FORMAT_STATE_NONE; 2585 goto qualifier; 2586 } 2587 2588 /* By default */ 2589 fmt.state = FORMAT_STATE_NONE; 2590 2591 for (; *fmt.str ; fmt.str++) { 2592 if (*fmt.str == '%') 2593 break; 2594 } 2595 2596 /* Return the current non-format string */ 2597 if (fmt.str != start || !*fmt.str) 2598 return fmt; 2599 2600 /* Process flags. This also skips the first '%' */ 2601 spec->flags = 0; 2602 do { 2603 /* this also skips first '%' */ 2604 flag = spec_flag(*++fmt.str); 2605 spec->flags |= flag; 2606 } while (flag); 2607 2608 /* get field width */ 2609 spec->field_width = -1; 2610 2611 if (isdigit(*fmt.str)) 2612 spec->field_width = skip_atoi(&fmt.str); 2613 else if (unlikely(*fmt.str == '*')) { 2614 /* it's the next argument */ 2615 fmt.state = FORMAT_STATE_WIDTH; 2616 fmt.str++; 2617 return fmt; 2618 } 2619 2620 precision: 2621 /* get the precision */ 2622 spec->precision = -1; 2623 if (unlikely(*fmt.str == '.')) { 2624 fmt.str++; 2625 if (isdigit(*fmt.str)) { 2626 spec->precision = skip_atoi(&fmt.str); 2627 if (spec->precision < 0) 2628 spec->precision = 0; 2629 } else if (*fmt.str == '*') { 2630 /* it's the next argument */ 2631 fmt.state = FORMAT_STATE_PRECISION; 2632 fmt.str++; 2633 return fmt; 2634 } 2635 } 2636 2637 qualifier: 2638 /* Set up default numeric format */ 2639 spec->base = 10; 2640 fmt.state = FORMAT_STATE_NUM; 2641 fmt.size = sizeof(int); 2642 static const struct format_state { 2643 unsigned char state; 2644 unsigned char size; 2645 unsigned char flags_or_double_size; 2646 unsigned char base; 2647 } lookup_state[256] = { 2648 // Length 2649 ['l'] = { 0, sizeof(long), sizeof(long long) }, 2650 ['L'] = { 0, sizeof(long long) }, 2651 ['h'] = { 0, sizeof(short), sizeof(char) }, 2652 ['H'] = { 0, sizeof(char) }, // Questionable historical 2653 ['z'] = { 0, sizeof(size_t) }, 2654 ['t'] = { 0, sizeof(ptrdiff_t) }, 2655 2656 // Non-numeric formats 2657 ['c'] = { FORMAT_STATE_CHAR }, 2658 ['s'] = { FORMAT_STATE_STR }, 2659 ['p'] = { FORMAT_STATE_PTR }, 2660 ['%'] = { FORMAT_STATE_PERCENT_CHAR }, 2661 2662 // Numerics 2663 ['o'] = { FORMAT_STATE_NUM, 0, 0, 8 }, 2664 ['x'] = { FORMAT_STATE_NUM, 0, SMALL, 16 }, 2665 ['X'] = { FORMAT_STATE_NUM, 0, 0, 16 }, 2666 ['d'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2667 ['i'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2668 ['u'] = { FORMAT_STATE_NUM, 0, 0, 10, }, 2669 2670 /* 2671 * Since %n poses a greater security risk than 2672 * utility, treat it as any other invalid or 2673 * unsupported format specifier. 2674 */ 2675 }; 2676 2677 const struct format_state *p = lookup_state + (u8)*fmt.str; 2678 if (p->size) { 2679 fmt.size = p->size; 2680 if (p->flags_or_double_size && fmt.str[0] == fmt.str[1]) { 2681 fmt.size = p->flags_or_double_size; 2682 fmt.str++; 2683 } 2684 fmt.str++; 2685 p = lookup_state + *fmt.str; 2686 } 2687 if (p->state) { 2688 if (p->base) 2689 spec->base = p->base; 2690 spec->flags |= p->flags_or_double_size; 2691 fmt.state = p->state; 2692 fmt.str++; 2693 return fmt; 2694 } 2695 2696 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt.str); 2697 fmt.state = FORMAT_STATE_INVALID; 2698 return fmt; 2699 } 2700 2701 static void 2702 set_field_width(struct printf_spec *spec, int width) 2703 { 2704 spec->field_width = width; 2705 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2706 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2707 } 2708 } 2709 2710 static void 2711 set_precision(struct printf_spec *spec, int prec) 2712 { 2713 spec->precision = prec; 2714 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2715 spec->precision = clamp(prec, 0, PRECISION_MAX); 2716 } 2717 } 2718 2719 /* 2720 * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate 2721 * as necessary and deal with signedness. 2722 * 2723 * 'size' is the size of the value in bytes. 2724 */ 2725 static unsigned long long convert_num_spec(unsigned int val, int size, struct printf_spec spec) 2726 { 2727 unsigned int shift = 32 - size*8; 2728 2729 val <<= shift; 2730 if (!(spec.flags & SIGN)) 2731 return val >> shift; 2732 return (int)val >> shift; 2733 } 2734 2735 /** 2736 * vsnprintf - Format a string and place it in a buffer 2737 * @buf: The buffer to place the result into 2738 * @size: The size of the buffer, including the trailing null space 2739 * @fmt_str: The format string to use 2740 * @args: Arguments for the format string 2741 * 2742 * This function generally follows C99 vsnprintf, but has some 2743 * extensions and a few limitations: 2744 * 2745 * - ``%n`` is unsupported 2746 * - ``%p*`` is handled by pointer() 2747 * 2748 * See pointer() or Documentation/core-api/printk-formats.rst for more 2749 * extensive description. 2750 * 2751 * **Please update the documentation in both places when making changes** 2752 * 2753 * The return value is the number of characters which would 2754 * be generated for the given input, excluding the trailing 2755 * '\0', as per ISO C99. If you want to have the exact 2756 * number of characters written into @buf as return value 2757 * (not including the trailing '\0'), use vscnprintf(). If the 2758 * return is greater than or equal to @size, the resulting 2759 * string is truncated. 2760 * 2761 * If you're not already dealing with a va_list consider using snprintf(). 2762 */ 2763 int vsnprintf(char *buf, size_t size, const char *fmt_str, va_list args) 2764 { 2765 char *str, *end; 2766 struct printf_spec spec = {0}; 2767 struct fmt fmt = { 2768 .str = fmt_str, 2769 .state = FORMAT_STATE_NONE, 2770 }; 2771 2772 /* Reject out-of-range values early. Large positive sizes are 2773 used for unknown buffer sizes. */ 2774 if (WARN_ON_ONCE(size > INT_MAX)) 2775 return 0; 2776 2777 str = buf; 2778 end = buf + size; 2779 2780 /* Make sure end is always >= buf */ 2781 if (end < buf) { 2782 end = ((void *)-1); 2783 size = end - buf; 2784 } 2785 2786 while (*fmt.str) { 2787 const char *old_fmt = fmt.str; 2788 2789 fmt = format_decode(fmt, &spec); 2790 2791 switch (fmt.state) { 2792 case FORMAT_STATE_NONE: { 2793 int read = fmt.str - old_fmt; 2794 if (str < end) { 2795 int copy = read; 2796 if (copy > end - str) 2797 copy = end - str; 2798 memcpy(str, old_fmt, copy); 2799 } 2800 str += read; 2801 continue; 2802 } 2803 2804 case FORMAT_STATE_NUM: { 2805 unsigned long long num; 2806 if (fmt.size <= sizeof(int)) 2807 num = convert_num_spec(va_arg(args, int), fmt.size, spec); 2808 else 2809 num = va_arg(args, long long); 2810 str = number(str, end, num, spec); 2811 continue; 2812 } 2813 2814 case FORMAT_STATE_WIDTH: 2815 set_field_width(&spec, va_arg(args, int)); 2816 continue; 2817 2818 case FORMAT_STATE_PRECISION: 2819 set_precision(&spec, va_arg(args, int)); 2820 continue; 2821 2822 case FORMAT_STATE_CHAR: { 2823 char c; 2824 2825 if (!(spec.flags & LEFT)) { 2826 while (--spec.field_width > 0) { 2827 if (str < end) 2828 *str = ' '; 2829 ++str; 2830 2831 } 2832 } 2833 c = (unsigned char) va_arg(args, int); 2834 if (str < end) 2835 *str = c; 2836 ++str; 2837 while (--spec.field_width > 0) { 2838 if (str < end) 2839 *str = ' '; 2840 ++str; 2841 } 2842 continue; 2843 } 2844 2845 case FORMAT_STATE_STR: 2846 str = string(str, end, va_arg(args, char *), spec); 2847 continue; 2848 2849 case FORMAT_STATE_PTR: 2850 str = pointer(fmt.str, str, end, va_arg(args, void *), 2851 spec); 2852 while (isalnum(*fmt.str)) 2853 fmt.str++; 2854 continue; 2855 2856 case FORMAT_STATE_PERCENT_CHAR: 2857 if (str < end) 2858 *str = '%'; 2859 ++str; 2860 continue; 2861 2862 default: 2863 /* 2864 * Presumably the arguments passed gcc's type 2865 * checking, but there is no safe or sane way 2866 * for us to continue parsing the format and 2867 * fetching from the va_list; the remaining 2868 * specifiers and arguments would be out of 2869 * sync. 2870 */ 2871 goto out; 2872 } 2873 } 2874 2875 out: 2876 if (size > 0) { 2877 if (str < end) 2878 *str = '\0'; 2879 else 2880 end[-1] = '\0'; 2881 } 2882 2883 /* the trailing null byte doesn't count towards the total */ 2884 return str-buf; 2885 2886 } 2887 EXPORT_SYMBOL(vsnprintf); 2888 2889 /** 2890 * vscnprintf - Format a string and place it in a buffer 2891 * @buf: The buffer to place the result into 2892 * @size: The size of the buffer, including the trailing null space 2893 * @fmt: The format string to use 2894 * @args: Arguments for the format string 2895 * 2896 * The return value is the number of characters which have been written into 2897 * the @buf not including the trailing '\0'. If @size is == 0 the function 2898 * returns 0. 2899 * 2900 * If you're not already dealing with a va_list consider using scnprintf(). 2901 * 2902 * See the vsnprintf() documentation for format string extensions over C99. 2903 */ 2904 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2905 { 2906 int i; 2907 2908 if (unlikely(!size)) 2909 return 0; 2910 2911 i = vsnprintf(buf, size, fmt, args); 2912 2913 if (likely(i < size)) 2914 return i; 2915 2916 return size - 1; 2917 } 2918 EXPORT_SYMBOL(vscnprintf); 2919 2920 /** 2921 * snprintf - Format a string and place it in a buffer 2922 * @buf: The buffer to place the result into 2923 * @size: The size of the buffer, including the trailing null space 2924 * @fmt: The format string to use 2925 * @...: Arguments for the format string 2926 * 2927 * The return value is the number of characters which would be 2928 * generated for the given input, excluding the trailing null, 2929 * as per ISO C99. If the return is greater than or equal to 2930 * @size, the resulting string is truncated. 2931 * 2932 * See the vsnprintf() documentation for format string extensions over C99. 2933 */ 2934 int snprintf(char *buf, size_t size, const char *fmt, ...) 2935 { 2936 va_list args; 2937 int i; 2938 2939 va_start(args, fmt); 2940 i = vsnprintf(buf, size, fmt, args); 2941 va_end(args); 2942 2943 return i; 2944 } 2945 EXPORT_SYMBOL(snprintf); 2946 2947 /** 2948 * scnprintf - Format a string and place it in a buffer 2949 * @buf: The buffer to place the result into 2950 * @size: The size of the buffer, including the trailing null space 2951 * @fmt: The format string to use 2952 * @...: Arguments for the format string 2953 * 2954 * The return value is the number of characters written into @buf not including 2955 * the trailing '\0'. If @size is == 0 the function returns 0. 2956 */ 2957 2958 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2959 { 2960 va_list args; 2961 int i; 2962 2963 va_start(args, fmt); 2964 i = vscnprintf(buf, size, fmt, args); 2965 va_end(args); 2966 2967 return i; 2968 } 2969 EXPORT_SYMBOL(scnprintf); 2970 2971 /** 2972 * vsprintf - Format a string and place it in a buffer 2973 * @buf: The buffer to place the result into 2974 * @fmt: The format string to use 2975 * @args: Arguments for the format string 2976 * 2977 * The function returns the number of characters written 2978 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2979 * buffer overflows. 2980 * 2981 * If you're not already dealing with a va_list consider using sprintf(). 2982 * 2983 * See the vsnprintf() documentation for format string extensions over C99. 2984 */ 2985 int vsprintf(char *buf, const char *fmt, va_list args) 2986 { 2987 return vsnprintf(buf, INT_MAX, fmt, args); 2988 } 2989 EXPORT_SYMBOL(vsprintf); 2990 2991 /** 2992 * sprintf - Format a string and place it in a buffer 2993 * @buf: The buffer to place the result into 2994 * @fmt: The format string to use 2995 * @...: Arguments for the format string 2996 * 2997 * The function returns the number of characters written 2998 * into @buf. Use snprintf() or scnprintf() in order to avoid 2999 * buffer overflows. 3000 * 3001 * See the vsnprintf() documentation for format string extensions over C99. 3002 */ 3003 int sprintf(char *buf, const char *fmt, ...) 3004 { 3005 va_list args; 3006 int i; 3007 3008 va_start(args, fmt); 3009 i = vsnprintf(buf, INT_MAX, fmt, args); 3010 va_end(args); 3011 3012 return i; 3013 } 3014 EXPORT_SYMBOL(sprintf); 3015 3016 #ifdef CONFIG_BINARY_PRINTF 3017 /* 3018 * bprintf service: 3019 * vbin_printf() - VA arguments to binary data 3020 * bstr_printf() - Binary data to text string 3021 */ 3022 3023 /** 3024 * vbin_printf - Parse a format string and place args' binary value in a buffer 3025 * @bin_buf: The buffer to place args' binary value 3026 * @size: The size of the buffer(by words(32bits), not characters) 3027 * @fmt_str: The format string to use 3028 * @args: Arguments for the format string 3029 * 3030 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3031 * is skipped. 3032 * 3033 * The return value is the number of words(32bits) which would be generated for 3034 * the given input. 3035 * 3036 * NOTE: 3037 * If the return value is greater than @size, the resulting bin_buf is NOT 3038 * valid for bstr_printf(). 3039 */ 3040 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt_str, va_list args) 3041 { 3042 struct fmt fmt = { 3043 .str = fmt_str, 3044 .state = FORMAT_STATE_NONE, 3045 }; 3046 struct printf_spec spec = {0}; 3047 char *str, *end; 3048 int width; 3049 3050 str = (char *)bin_buf; 3051 end = (char *)(bin_buf + size); 3052 3053 #define save_arg(type) \ 3054 ({ \ 3055 unsigned long long value; \ 3056 if (sizeof(type) == 8) { \ 3057 unsigned long long val8; \ 3058 str = PTR_ALIGN(str, sizeof(u32)); \ 3059 val8 = va_arg(args, unsigned long long); \ 3060 if (str + sizeof(type) <= end) { \ 3061 *(u32 *)str = *(u32 *)&val8; \ 3062 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3063 } \ 3064 value = val8; \ 3065 } else { \ 3066 unsigned int val4; \ 3067 str = PTR_ALIGN(str, sizeof(type)); \ 3068 val4 = va_arg(args, int); \ 3069 if (str + sizeof(type) <= end) \ 3070 *(typeof(type) *)str = (type)(long)val4; \ 3071 value = (unsigned long long)val4; \ 3072 } \ 3073 str += sizeof(type); \ 3074 value; \ 3075 }) 3076 3077 while (*fmt.str) { 3078 fmt = format_decode(fmt, &spec); 3079 3080 switch (fmt.state) { 3081 case FORMAT_STATE_NONE: 3082 case FORMAT_STATE_PERCENT_CHAR: 3083 break; 3084 case FORMAT_STATE_INVALID: 3085 goto out; 3086 3087 case FORMAT_STATE_WIDTH: 3088 case FORMAT_STATE_PRECISION: 3089 width = (int)save_arg(int); 3090 /* Pointers may require the width */ 3091 if (*fmt.str == 'p') 3092 set_field_width(&spec, width); 3093 break; 3094 3095 case FORMAT_STATE_CHAR: 3096 save_arg(char); 3097 break; 3098 3099 case FORMAT_STATE_STR: { 3100 const char *save_str = va_arg(args, char *); 3101 const char *err_msg; 3102 size_t len; 3103 3104 err_msg = check_pointer_msg(save_str); 3105 if (err_msg) 3106 save_str = err_msg; 3107 3108 len = strlen(save_str) + 1; 3109 if (str + len < end) 3110 memcpy(str, save_str, len); 3111 str += len; 3112 break; 3113 } 3114 3115 case FORMAT_STATE_PTR: 3116 /* Dereferenced pointers must be done now */ 3117 switch (*fmt.str) { 3118 /* Dereference of functions is still OK */ 3119 case 'S': 3120 case 's': 3121 case 'x': 3122 case 'K': 3123 case 'e': 3124 save_arg(void *); 3125 break; 3126 default: 3127 if (!isalnum(*fmt.str)) { 3128 save_arg(void *); 3129 break; 3130 } 3131 str = pointer(fmt.str, str, end, va_arg(args, void *), 3132 spec); 3133 if (str + 1 < end) 3134 *str++ = '\0'; 3135 else 3136 end[-1] = '\0'; /* Must be nul terminated */ 3137 } 3138 /* skip all alphanumeric pointer suffixes */ 3139 while (isalnum(*fmt.str)) 3140 fmt.str++; 3141 break; 3142 3143 case FORMAT_STATE_NUM: 3144 if (fmt.size > sizeof(int)) { 3145 save_arg(long long); 3146 } else { 3147 save_arg(int); 3148 } 3149 } 3150 } 3151 3152 out: 3153 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3154 #undef save_arg 3155 } 3156 EXPORT_SYMBOL_GPL(vbin_printf); 3157 3158 /** 3159 * bstr_printf - Format a string from binary arguments and place it in a buffer 3160 * @buf: The buffer to place the result into 3161 * @size: The size of the buffer, including the trailing null space 3162 * @fmt_str: The format string to use 3163 * @bin_buf: Binary arguments for the format string 3164 * 3165 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3166 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3167 * a binary buffer that generated by vbin_printf. 3168 * 3169 * The format follows C99 vsnprintf, but has some extensions: 3170 * see vsnprintf comment for details. 3171 * 3172 * The return value is the number of characters which would 3173 * be generated for the given input, excluding the trailing 3174 * '\0', as per ISO C99. If you want to have the exact 3175 * number of characters written into @buf as return value 3176 * (not including the trailing '\0'), use vscnprintf(). If the 3177 * return is greater than or equal to @size, the resulting 3178 * string is truncated. 3179 */ 3180 int bstr_printf(char *buf, size_t size, const char *fmt_str, const u32 *bin_buf) 3181 { 3182 struct fmt fmt = { 3183 .str = fmt_str, 3184 .state = FORMAT_STATE_NONE, 3185 }; 3186 struct printf_spec spec = {0}; 3187 char *str, *end; 3188 const char *args = (const char *)bin_buf; 3189 3190 if (WARN_ON_ONCE(size > INT_MAX)) 3191 return 0; 3192 3193 str = buf; 3194 end = buf + size; 3195 3196 #define get_arg(type) \ 3197 ({ \ 3198 typeof(type) value; \ 3199 if (sizeof(type) == 8) { \ 3200 args = PTR_ALIGN(args, sizeof(u32)); \ 3201 *(u32 *)&value = *(u32 *)args; \ 3202 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3203 } else { \ 3204 args = PTR_ALIGN(args, sizeof(type)); \ 3205 value = *(typeof(type) *)args; \ 3206 } \ 3207 args += sizeof(type); \ 3208 value; \ 3209 }) 3210 3211 /* Make sure end is always >= buf */ 3212 if (end < buf) { 3213 end = ((void *)-1); 3214 size = end - buf; 3215 } 3216 3217 while (*fmt.str) { 3218 const char *old_fmt = fmt.str; 3219 unsigned long long num; 3220 3221 fmt = format_decode(fmt, &spec); 3222 switch (fmt.state) { 3223 case FORMAT_STATE_NONE: { 3224 int read = fmt.str - old_fmt; 3225 if (str < end) { 3226 int copy = read; 3227 if (copy > end - str) 3228 copy = end - str; 3229 memcpy(str, old_fmt, copy); 3230 } 3231 str += read; 3232 continue; 3233 } 3234 3235 case FORMAT_STATE_WIDTH: 3236 set_field_width(&spec, get_arg(int)); 3237 continue; 3238 3239 case FORMAT_STATE_PRECISION: 3240 set_precision(&spec, get_arg(int)); 3241 continue; 3242 3243 case FORMAT_STATE_CHAR: { 3244 char c; 3245 3246 if (!(spec.flags & LEFT)) { 3247 while (--spec.field_width > 0) { 3248 if (str < end) 3249 *str = ' '; 3250 ++str; 3251 } 3252 } 3253 c = (unsigned char) get_arg(char); 3254 if (str < end) 3255 *str = c; 3256 ++str; 3257 while (--spec.field_width > 0) { 3258 if (str < end) 3259 *str = ' '; 3260 ++str; 3261 } 3262 continue; 3263 } 3264 3265 case FORMAT_STATE_STR: { 3266 const char *str_arg = args; 3267 args += strlen(str_arg) + 1; 3268 str = string(str, end, (char *)str_arg, spec); 3269 continue; 3270 } 3271 3272 case FORMAT_STATE_PTR: { 3273 bool process = false; 3274 int copy, len; 3275 /* Non function dereferences were already done */ 3276 switch (*fmt.str) { 3277 case 'S': 3278 case 's': 3279 case 'x': 3280 case 'K': 3281 case 'e': 3282 process = true; 3283 break; 3284 default: 3285 if (!isalnum(*fmt.str)) { 3286 process = true; 3287 break; 3288 } 3289 /* Pointer dereference was already processed */ 3290 if (str < end) { 3291 len = copy = strlen(args); 3292 if (copy > end - str) 3293 copy = end - str; 3294 memcpy(str, args, copy); 3295 str += len; 3296 args += len + 1; 3297 } 3298 } 3299 if (process) 3300 str = pointer(fmt.str, str, end, get_arg(void *), spec); 3301 3302 while (isalnum(*fmt.str)) 3303 fmt.str++; 3304 continue; 3305 } 3306 3307 case FORMAT_STATE_PERCENT_CHAR: 3308 if (str < end) 3309 *str = '%'; 3310 ++str; 3311 continue; 3312 3313 case FORMAT_STATE_INVALID: 3314 goto out; 3315 3316 case FORMAT_STATE_NUM: 3317 if (fmt.size > sizeof(int)) { 3318 num = get_arg(long long); 3319 } else { 3320 num = convert_num_spec(get_arg(int), fmt.size, spec); 3321 } 3322 str = number(str, end, num, spec); 3323 continue; 3324 } 3325 } /* while(*fmt.str) */ 3326 3327 out: 3328 if (size > 0) { 3329 if (str < end) 3330 *str = '\0'; 3331 else 3332 end[-1] = '\0'; 3333 } 3334 3335 #undef get_arg 3336 3337 /* the trailing null byte doesn't count towards the total */ 3338 return str - buf; 3339 } 3340 EXPORT_SYMBOL_GPL(bstr_printf); 3341 3342 #endif /* CONFIG_BINARY_PRINTF */ 3343 3344 /** 3345 * vsscanf - Unformat a buffer into a list of arguments 3346 * @buf: input buffer 3347 * @fmt: format of buffer 3348 * @args: arguments 3349 */ 3350 int vsscanf(const char *buf, const char *fmt, va_list args) 3351 { 3352 const char *str = buf; 3353 char *next; 3354 char digit; 3355 int num = 0; 3356 u8 qualifier; 3357 unsigned int base; 3358 union { 3359 long long s; 3360 unsigned long long u; 3361 } val; 3362 s16 field_width; 3363 bool is_sign; 3364 3365 while (*fmt) { 3366 /* skip any white space in format */ 3367 /* white space in format matches any amount of 3368 * white space, including none, in the input. 3369 */ 3370 if (isspace(*fmt)) { 3371 fmt = skip_spaces(++fmt); 3372 str = skip_spaces(str); 3373 } 3374 3375 /* anything that is not a conversion must match exactly */ 3376 if (*fmt != '%' && *fmt) { 3377 if (*fmt++ != *str++) 3378 break; 3379 continue; 3380 } 3381 3382 if (!*fmt) 3383 break; 3384 ++fmt; 3385 3386 /* skip this conversion. 3387 * advance both strings to next white space 3388 */ 3389 if (*fmt == '*') { 3390 if (!*str) 3391 break; 3392 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3393 /* '%*[' not yet supported, invalid format */ 3394 if (*fmt == '[') 3395 return num; 3396 fmt++; 3397 } 3398 while (!isspace(*str) && *str) 3399 str++; 3400 continue; 3401 } 3402 3403 /* get field width */ 3404 field_width = -1; 3405 if (isdigit(*fmt)) { 3406 field_width = skip_atoi(&fmt); 3407 if (field_width <= 0) 3408 break; 3409 } 3410 3411 /* get conversion qualifier */ 3412 qualifier = -1; 3413 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3414 *fmt == 'z') { 3415 qualifier = *fmt++; 3416 if (unlikely(qualifier == *fmt)) { 3417 if (qualifier == 'h') { 3418 qualifier = 'H'; 3419 fmt++; 3420 } else if (qualifier == 'l') { 3421 qualifier = 'L'; 3422 fmt++; 3423 } 3424 } 3425 } 3426 3427 if (!*fmt) 3428 break; 3429 3430 if (*fmt == 'n') { 3431 /* return number of characters read so far */ 3432 *va_arg(args, int *) = str - buf; 3433 ++fmt; 3434 continue; 3435 } 3436 3437 if (!*str) 3438 break; 3439 3440 base = 10; 3441 is_sign = false; 3442 3443 switch (*fmt++) { 3444 case 'c': 3445 { 3446 char *s = (char *)va_arg(args, char*); 3447 if (field_width == -1) 3448 field_width = 1; 3449 do { 3450 *s++ = *str++; 3451 } while (--field_width > 0 && *str); 3452 num++; 3453 } 3454 continue; 3455 case 's': 3456 { 3457 char *s = (char *)va_arg(args, char *); 3458 if (field_width == -1) 3459 field_width = SHRT_MAX; 3460 /* first, skip leading white space in buffer */ 3461 str = skip_spaces(str); 3462 3463 /* now copy until next white space */ 3464 while (*str && !isspace(*str) && field_width--) 3465 *s++ = *str++; 3466 *s = '\0'; 3467 num++; 3468 } 3469 continue; 3470 /* 3471 * Warning: This implementation of the '[' conversion specifier 3472 * deviates from its glibc counterpart in the following ways: 3473 * (1) It does NOT support ranges i.e. '-' is NOT a special 3474 * character 3475 * (2) It cannot match the closing bracket ']' itself 3476 * (3) A field width is required 3477 * (4) '%*[' (discard matching input) is currently not supported 3478 * 3479 * Example usage: 3480 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3481 * buf1, buf2, buf3); 3482 * if (ret < 3) 3483 * // etc.. 3484 */ 3485 case '[': 3486 { 3487 char *s = (char *)va_arg(args, char *); 3488 DECLARE_BITMAP(set, 256) = {0}; 3489 unsigned int len = 0; 3490 bool negate = (*fmt == '^'); 3491 3492 /* field width is required */ 3493 if (field_width == -1) 3494 return num; 3495 3496 if (negate) 3497 ++fmt; 3498 3499 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3500 __set_bit((u8)*fmt, set); 3501 3502 /* no ']' or no character set found */ 3503 if (!*fmt || !len) 3504 return num; 3505 ++fmt; 3506 3507 if (negate) { 3508 bitmap_complement(set, set, 256); 3509 /* exclude null '\0' byte */ 3510 __clear_bit(0, set); 3511 } 3512 3513 /* match must be non-empty */ 3514 if (!test_bit((u8)*str, set)) 3515 return num; 3516 3517 while (test_bit((u8)*str, set) && field_width--) 3518 *s++ = *str++; 3519 *s = '\0'; 3520 ++num; 3521 } 3522 continue; 3523 case 'o': 3524 base = 8; 3525 break; 3526 case 'x': 3527 case 'X': 3528 base = 16; 3529 break; 3530 case 'i': 3531 base = 0; 3532 fallthrough; 3533 case 'd': 3534 is_sign = true; 3535 fallthrough; 3536 case 'u': 3537 break; 3538 case '%': 3539 /* looking for '%' in str */ 3540 if (*str++ != '%') 3541 return num; 3542 continue; 3543 default: 3544 /* invalid format; stop here */ 3545 return num; 3546 } 3547 3548 /* have some sort of integer conversion. 3549 * first, skip white space in buffer. 3550 */ 3551 str = skip_spaces(str); 3552 3553 digit = *str; 3554 if (is_sign && digit == '-') { 3555 if (field_width == 1) 3556 break; 3557 3558 digit = *(str + 1); 3559 } 3560 3561 if (!digit 3562 || (base == 16 && !isxdigit(digit)) 3563 || (base == 10 && !isdigit(digit)) 3564 || (base == 8 && !isodigit(digit)) 3565 || (base == 0 && !isdigit(digit))) 3566 break; 3567 3568 if (is_sign) 3569 val.s = simple_strntoll(str, &next, base, 3570 field_width >= 0 ? field_width : INT_MAX); 3571 else 3572 val.u = simple_strntoull(str, &next, base, 3573 field_width >= 0 ? field_width : INT_MAX); 3574 3575 switch (qualifier) { 3576 case 'H': /* that's 'hh' in format */ 3577 if (is_sign) 3578 *va_arg(args, signed char *) = val.s; 3579 else 3580 *va_arg(args, unsigned char *) = val.u; 3581 break; 3582 case 'h': 3583 if (is_sign) 3584 *va_arg(args, short *) = val.s; 3585 else 3586 *va_arg(args, unsigned short *) = val.u; 3587 break; 3588 case 'l': 3589 if (is_sign) 3590 *va_arg(args, long *) = val.s; 3591 else 3592 *va_arg(args, unsigned long *) = val.u; 3593 break; 3594 case 'L': 3595 if (is_sign) 3596 *va_arg(args, long long *) = val.s; 3597 else 3598 *va_arg(args, unsigned long long *) = val.u; 3599 break; 3600 case 'z': 3601 *va_arg(args, size_t *) = val.u; 3602 break; 3603 default: 3604 if (is_sign) 3605 *va_arg(args, int *) = val.s; 3606 else 3607 *va_arg(args, unsigned int *) = val.u; 3608 break; 3609 } 3610 num++; 3611 3612 if (!next) 3613 break; 3614 str = next; 3615 } 3616 3617 return num; 3618 } 3619 EXPORT_SYMBOL(vsscanf); 3620 3621 /** 3622 * sscanf - Unformat a buffer into a list of arguments 3623 * @buf: input buffer 3624 * @fmt: formatting of buffer 3625 * @...: resulting arguments 3626 */ 3627 int sscanf(const char *buf, const char *fmt, ...) 3628 { 3629 va_list args; 3630 int i; 3631 3632 va_start(args, fmt); 3633 i = vsscanf(buf, fmt, args); 3634 va_end(args); 3635 3636 return i; 3637 } 3638 EXPORT_SYMBOL(sscanf); 3639