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 <[email protected]> 15 * - changed to provide snprintf and vsnprintf functions 16 * So Feb 1 16:51:32 CET 2004 Juergen Quade <[email protected]> 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 /** 118 * simple_strtol - convert a string to a signed long 119 * @cp: The start of the string 120 * @endp: A pointer to the end of the parsed string will be placed here 121 * @base: The number base to use 122 * 123 * This function has caveats. Please use kstrtol instead. 124 */ 125 long simple_strtol(const char *cp, char **endp, unsigned int base) 126 { 127 if (*cp == '-') 128 return -simple_strtoul(cp + 1, endp, base); 129 130 return simple_strtoul(cp, endp, base); 131 } 132 EXPORT_SYMBOL(simple_strtol); 133 134 noinline 135 static long long simple_strntoll(const char *cp, char **endp, unsigned int base, size_t max_chars) 136 { 137 /* 138 * simple_strntoull() safely handles receiving max_chars==0 in the 139 * case cp[0] == '-' && max_chars == 1. 140 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 141 * and the content of *cp is irrelevant. 142 */ 143 if (*cp == '-' && max_chars > 0) 144 return -simple_strntoull(cp + 1, endp, base, max_chars - 1); 145 146 return simple_strntoull(cp, endp, base, max_chars); 147 } 148 149 /** 150 * simple_strtoll - convert a string to a signed long long 151 * @cp: The start of the string 152 * @endp: A pointer to the end of the parsed string will be placed here 153 * @base: The number base to use 154 * 155 * This function has caveats. Please use kstrtoll instead. 156 */ 157 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 158 { 159 return simple_strntoll(cp, endp, base, INT_MAX); 160 } 161 EXPORT_SYMBOL(simple_strtoll); 162 163 static noinline_for_stack 164 int skip_atoi(const char **s) 165 { 166 int i = 0; 167 168 do { 169 i = i*10 + *((*s)++) - '0'; 170 } while (isdigit(**s)); 171 172 return i; 173 } 174 175 /* 176 * Decimal conversion is by far the most typical, and is used for 177 * /proc and /sys data. This directly impacts e.g. top performance 178 * with many processes running. We optimize it for speed by emitting 179 * two characters at a time, using a 200 byte lookup table. This 180 * roughly halves the number of multiplications compared to computing 181 * the digits one at a time. Implementation strongly inspired by the 182 * previous version, which in turn used ideas described at 183 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 184 * from the author, Douglas W. Jones). 185 * 186 * It turns out there is precisely one 26 bit fixed-point 187 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 188 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 189 * range happens to be somewhat larger (x <= 1073741898), but that's 190 * irrelevant for our purpose. 191 * 192 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 193 * need a 32x32->64 bit multiply, so we simply use the same constant. 194 * 195 * For dividing a number in the range [100, 10^4-1] by 100, there are 196 * several options. The simplest is (x * 0x147b) >> 19, which is valid 197 * for all x <= 43698. 198 */ 199 200 static const u16 decpair[100] = { 201 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 202 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 203 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 204 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 205 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 206 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 207 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 208 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 209 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 210 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 211 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 212 #undef _ 213 }; 214 215 /* 216 * This will print a single '0' even if r == 0, since we would 217 * immediately jump to out_r where two 0s would be written but only 218 * one of them accounted for in buf. This is needed by ip4_string 219 * below. All other callers pass a non-zero value of r. 220 */ 221 static noinline_for_stack 222 char *put_dec_trunc8(char *buf, unsigned r) 223 { 224 unsigned q; 225 226 /* 1 <= r < 10^8 */ 227 if (r < 100) 228 goto out_r; 229 230 /* 100 <= r < 10^8 */ 231 q = (r * (u64)0x28f5c29) >> 32; 232 *((u16 *)buf) = decpair[r - 100*q]; 233 buf += 2; 234 235 /* 1 <= q < 10^6 */ 236 if (q < 100) 237 goto out_q; 238 239 /* 100 <= q < 10^6 */ 240 r = (q * (u64)0x28f5c29) >> 32; 241 *((u16 *)buf) = decpair[q - 100*r]; 242 buf += 2; 243 244 /* 1 <= r < 10^4 */ 245 if (r < 100) 246 goto out_r; 247 248 /* 100 <= r < 10^4 */ 249 q = (r * 0x147b) >> 19; 250 *((u16 *)buf) = decpair[r - 100*q]; 251 buf += 2; 252 out_q: 253 /* 1 <= q < 100 */ 254 r = q; 255 out_r: 256 /* 1 <= r < 100 */ 257 *((u16 *)buf) = decpair[r]; 258 buf += r < 10 ? 1 : 2; 259 return buf; 260 } 261 262 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 263 static noinline_for_stack 264 char *put_dec_full8(char *buf, unsigned r) 265 { 266 unsigned q; 267 268 /* 0 <= r < 10^8 */ 269 q = (r * (u64)0x28f5c29) >> 32; 270 *((u16 *)buf) = decpair[r - 100*q]; 271 buf += 2; 272 273 /* 0 <= q < 10^6 */ 274 r = (q * (u64)0x28f5c29) >> 32; 275 *((u16 *)buf) = decpair[q - 100*r]; 276 buf += 2; 277 278 /* 0 <= r < 10^4 */ 279 q = (r * 0x147b) >> 19; 280 *((u16 *)buf) = decpair[r - 100*q]; 281 buf += 2; 282 283 /* 0 <= q < 100 */ 284 *((u16 *)buf) = decpair[q]; 285 buf += 2; 286 return buf; 287 } 288 289 static noinline_for_stack 290 char *put_dec(char *buf, unsigned long long n) 291 { 292 if (n >= 100*1000*1000) 293 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 294 /* 1 <= n <= 1.6e11 */ 295 if (n >= 100*1000*1000) 296 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 297 /* 1 <= n < 1e8 */ 298 return put_dec_trunc8(buf, n); 299 } 300 301 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 302 303 static void 304 put_dec_full4(char *buf, unsigned r) 305 { 306 unsigned q; 307 308 /* 0 <= r < 10^4 */ 309 q = (r * 0x147b) >> 19; 310 *((u16 *)buf) = decpair[r - 100*q]; 311 buf += 2; 312 /* 0 <= q < 100 */ 313 *((u16 *)buf) = decpair[q]; 314 } 315 316 /* 317 * Call put_dec_full4 on x % 10000, return x / 10000. 318 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 319 * holds for all x < 1,128,869,999. The largest value this 320 * helper will ever be asked to convert is 1,125,520,955. 321 * (second call in the put_dec code, assuming n is all-ones). 322 */ 323 static noinline_for_stack 324 unsigned put_dec_helper4(char *buf, unsigned x) 325 { 326 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 327 328 put_dec_full4(buf, x - q * 10000); 329 return q; 330 } 331 332 /* Based on code by Douglas W. Jones found at 333 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 334 * (with permission from the author). 335 * Performs no 64-bit division and hence should be fast on 32-bit machines. 336 */ 337 static 338 char *put_dec(char *buf, unsigned long long n) 339 { 340 uint32_t d3, d2, d1, q, h; 341 342 if (n < 100*1000*1000) 343 return put_dec_trunc8(buf, n); 344 345 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 346 h = (n >> 32); 347 d2 = (h ) & 0xffff; 348 d3 = (h >> 16); /* implicit "& 0xffff" */ 349 350 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 351 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 352 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 353 q = put_dec_helper4(buf, q); 354 355 q += 7671 * d3 + 9496 * d2 + 6 * d1; 356 q = put_dec_helper4(buf+4, q); 357 358 q += 4749 * d3 + 42 * d2; 359 q = put_dec_helper4(buf+8, q); 360 361 q += 281 * d3; 362 buf += 12; 363 if (q) 364 buf = put_dec_trunc8(buf, q); 365 else while (buf[-1] == '0') 366 --buf; 367 368 return buf; 369 } 370 371 #endif 372 373 /* 374 * Convert passed number to decimal string. 375 * Returns the length of string. On buffer overflow, returns 0. 376 * 377 * If speed is not important, use snprintf(). It's easy to read the code. 378 */ 379 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 380 { 381 /* put_dec requires 2-byte alignment of the buffer. */ 382 char tmp[sizeof(num) * 3] __aligned(2); 383 int idx, len; 384 385 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 386 if (num <= 9) { 387 tmp[0] = '0' + num; 388 len = 1; 389 } else { 390 len = put_dec(tmp, num) - tmp; 391 } 392 393 if (len > size || width > size) 394 return 0; 395 396 if (width > len) { 397 width = width - len; 398 for (idx = 0; idx < width; idx++) 399 buf[idx] = ' '; 400 } else { 401 width = 0; 402 } 403 404 for (idx = 0; idx < len; ++idx) 405 buf[idx + width] = tmp[len - idx - 1]; 406 407 return len + width; 408 } 409 410 #define SIGN 1 /* unsigned/signed */ 411 #define LEFT 2 /* left justified */ 412 #define PLUS 4 /* show plus */ 413 #define SPACE 8 /* space if plus */ 414 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 415 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 416 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 417 418 static_assert(ZEROPAD == ('0' - ' ')); 419 static_assert(SMALL == ('a' ^ 'A')); 420 421 enum format_type { 422 FORMAT_TYPE_NONE, /* Just a string part */ 423 FORMAT_TYPE_1BYTE = 1, /* char/short/int are their own sizes */ 424 FORMAT_TYPE_2BYTE = 2, 425 FORMAT_TYPE_8BYTE = 3, 426 FORMAT_TYPE_4BYTE = 4, 427 FORMAT_TYPE_WIDTH, 428 FORMAT_TYPE_PRECISION, 429 FORMAT_TYPE_CHAR, 430 FORMAT_TYPE_STR, 431 FORMAT_TYPE_PTR, 432 FORMAT_TYPE_PERCENT_CHAR, 433 FORMAT_TYPE_INVALID, 434 }; 435 436 #define FORMAT_TYPE_SIZE(type) (sizeof(type) <= 4 ? sizeof(type) : FORMAT_TYPE_8BYTE) 437 438 struct printf_spec { 439 unsigned int type:8; /* format_type enum */ 440 signed int field_width:24; /* width of output field */ 441 unsigned int flags:8; /* flags to number() */ 442 unsigned int base:8; /* number base, 8, 10 or 16 only */ 443 signed int precision:16; /* # of digits/chars */ 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.type = FORMAT_TYPE_PTR; 577 spec.field_width = 2 + 2 * size; /* 0x + hex */ 578 spec.flags = SPECIAL | SMALL | ZEROPAD; 579 spec.base = 16; 580 spec.precision = -1; 581 582 return number(buf, end, num, spec); 583 } 584 585 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 586 { 587 size_t size; 588 if (buf >= end) /* nowhere to put anything */ 589 return; 590 size = end - buf; 591 if (size <= spaces) { 592 memset(buf, ' ', size); 593 return; 594 } 595 if (len) { 596 if (len > size - spaces) 597 len = size - spaces; 598 memmove(buf + spaces, buf, len); 599 } 600 memset(buf, ' ', spaces); 601 } 602 603 /* 604 * Handle field width padding for a string. 605 * @buf: current buffer position 606 * @n: length of string 607 * @end: end of output buffer 608 * @spec: for field width and flags 609 * Returns: new buffer position after padding. 610 */ 611 static noinline_for_stack 612 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 613 { 614 unsigned spaces; 615 616 if (likely(n >= spec.field_width)) 617 return buf; 618 /* we want to pad the sucker */ 619 spaces = spec.field_width - n; 620 if (!(spec.flags & LEFT)) { 621 move_right(buf - n, end, n, spaces); 622 return buf + spaces; 623 } 624 while (spaces--) { 625 if (buf < end) 626 *buf = ' '; 627 ++buf; 628 } 629 return buf; 630 } 631 632 /* Handle string from a well known address. */ 633 static char *string_nocheck(char *buf, char *end, const char *s, 634 struct printf_spec spec) 635 { 636 int len = 0; 637 int lim = spec.precision; 638 639 while (lim--) { 640 char c = *s++; 641 if (!c) 642 break; 643 if (buf < end) 644 *buf = c; 645 ++buf; 646 ++len; 647 } 648 return widen_string(buf, len, end, spec); 649 } 650 651 static char *err_ptr(char *buf, char *end, void *ptr, 652 struct printf_spec spec) 653 { 654 int err = PTR_ERR(ptr); 655 const char *sym = errname(err); 656 657 if (sym) 658 return string_nocheck(buf, end, sym, spec); 659 660 /* 661 * Somebody passed ERR_PTR(-1234) or some other non-existing 662 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 663 * printing it as its decimal representation. 664 */ 665 spec.flags |= SIGN; 666 spec.base = 10; 667 return number(buf, end, err, spec); 668 } 669 670 /* Be careful: error messages must fit into the given buffer. */ 671 static char *error_string(char *buf, char *end, const char *s, 672 struct printf_spec spec) 673 { 674 /* 675 * Hard limit to avoid a completely insane messages. It actually 676 * works pretty well because most error messages are in 677 * the many pointer format modifiers. 678 */ 679 if (spec.precision == -1) 680 spec.precision = 2 * sizeof(void *); 681 682 return string_nocheck(buf, end, s, spec); 683 } 684 685 /* 686 * Do not call any complex external code here. Nested printk()/vsprintf() 687 * might cause infinite loops. Failures might break printk() and would 688 * be hard to debug. 689 */ 690 static const char *check_pointer_msg(const void *ptr) 691 { 692 if (!ptr) 693 return "(null)"; 694 695 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 696 return "(efault)"; 697 698 return NULL; 699 } 700 701 static int check_pointer(char **buf, char *end, const void *ptr, 702 struct printf_spec spec) 703 { 704 const char *err_msg; 705 706 err_msg = check_pointer_msg(ptr); 707 if (err_msg) { 708 *buf = error_string(*buf, end, err_msg, spec); 709 return -EFAULT; 710 } 711 712 return 0; 713 } 714 715 static noinline_for_stack 716 char *string(char *buf, char *end, const char *s, 717 struct printf_spec spec) 718 { 719 if (check_pointer(&buf, end, s, spec)) 720 return buf; 721 722 return string_nocheck(buf, end, s, spec); 723 } 724 725 static char *pointer_string(char *buf, char *end, 726 const void *ptr, 727 struct printf_spec spec) 728 { 729 spec.base = 16; 730 spec.flags |= SMALL; 731 if (spec.field_width == -1) { 732 spec.field_width = 2 * sizeof(ptr); 733 spec.flags |= ZEROPAD; 734 } 735 736 return number(buf, end, (unsigned long int)ptr, spec); 737 } 738 739 /* Make pointers available for printing early in the boot sequence. */ 740 static int debug_boot_weak_hash __ro_after_init; 741 742 static int __init debug_boot_weak_hash_enable(char *str) 743 { 744 debug_boot_weak_hash = 1; 745 pr_info("debug_boot_weak_hash enabled\n"); 746 return 0; 747 } 748 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 749 750 static bool filled_random_ptr_key __read_mostly; 751 static siphash_key_t ptr_key __read_mostly; 752 753 static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) 754 { 755 get_random_bytes(&ptr_key, sizeof(ptr_key)); 756 757 /* Pairs with smp_rmb() before reading ptr_key. */ 758 smp_wmb(); 759 WRITE_ONCE(filled_random_ptr_key, true); 760 return NOTIFY_DONE; 761 } 762 763 static int __init vsprintf_init_hashval(void) 764 { 765 static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; 766 execute_with_initialized_rng(&fill_ptr_key_nb); 767 return 0; 768 } 769 subsys_initcall(vsprintf_init_hashval) 770 771 /* Maps a pointer to a 32 bit unique identifier. */ 772 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 773 { 774 unsigned long hashval; 775 776 if (!READ_ONCE(filled_random_ptr_key)) 777 return -EBUSY; 778 779 /* Pairs with smp_wmb() after writing ptr_key. */ 780 smp_rmb(); 781 782 #ifdef CONFIG_64BIT 783 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 784 /* 785 * Mask off the first 32 bits, this makes explicit that we have 786 * modified the address (and 32 bits is plenty for a unique ID). 787 */ 788 hashval = hashval & 0xffffffff; 789 #else 790 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 791 #endif 792 *hashval_out = hashval; 793 return 0; 794 } 795 796 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 797 { 798 return __ptr_to_hashval(ptr, hashval_out); 799 } 800 801 static char *ptr_to_id(char *buf, char *end, const void *ptr, 802 struct printf_spec spec) 803 { 804 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 805 unsigned long hashval; 806 int ret; 807 808 /* 809 * Print the real pointer value for NULL and error pointers, 810 * as they are not actual addresses. 811 */ 812 if (IS_ERR_OR_NULL(ptr)) 813 return pointer_string(buf, end, ptr, spec); 814 815 /* When debugging early boot use non-cryptographically secure hash. */ 816 if (unlikely(debug_boot_weak_hash)) { 817 hashval = hash_long((unsigned long)ptr, 32); 818 return pointer_string(buf, end, (const void *)hashval, spec); 819 } 820 821 ret = __ptr_to_hashval(ptr, &hashval); 822 if (ret) { 823 spec.field_width = 2 * sizeof(ptr); 824 /* string length must be less than default_width */ 825 return error_string(buf, end, str, spec); 826 } 827 828 return pointer_string(buf, end, (const void *)hashval, spec); 829 } 830 831 static char *default_pointer(char *buf, char *end, const void *ptr, 832 struct printf_spec spec) 833 { 834 /* 835 * default is to _not_ leak addresses, so hash before printing, 836 * unless no_hash_pointers is specified on the command line. 837 */ 838 if (unlikely(no_hash_pointers)) 839 return pointer_string(buf, end, ptr, spec); 840 841 return ptr_to_id(buf, end, ptr, spec); 842 } 843 844 int kptr_restrict __read_mostly; 845 846 static noinline_for_stack 847 char *restricted_pointer(char *buf, char *end, const void *ptr, 848 struct printf_spec spec) 849 { 850 switch (kptr_restrict) { 851 case 0: 852 /* Handle as %p, hash and do _not_ leak addresses. */ 853 return default_pointer(buf, end, ptr, spec); 854 case 1: { 855 const struct cred *cred; 856 857 /* 858 * kptr_restrict==1 cannot be used in IRQ context 859 * because its test for CAP_SYSLOG would be meaningless. 860 */ 861 if (in_hardirq() || in_serving_softirq() || in_nmi()) { 862 if (spec.field_width == -1) 863 spec.field_width = 2 * sizeof(ptr); 864 return error_string(buf, end, "pK-error", spec); 865 } 866 867 /* 868 * Only print the real pointer value if the current 869 * process has CAP_SYSLOG and is running with the 870 * same credentials it started with. This is because 871 * access to files is checked at open() time, but %pK 872 * checks permission at read() time. We don't want to 873 * leak pointer values if a binary opens a file using 874 * %pK and then elevates privileges before reading it. 875 */ 876 cred = current_cred(); 877 if (!has_capability_noaudit(current, CAP_SYSLOG) || 878 !uid_eq(cred->euid, cred->uid) || 879 !gid_eq(cred->egid, cred->gid)) 880 ptr = NULL; 881 break; 882 } 883 case 2: 884 default: 885 /* Always print 0's for %pK */ 886 ptr = NULL; 887 break; 888 } 889 890 return pointer_string(buf, end, ptr, spec); 891 } 892 893 static noinline_for_stack 894 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 895 const char *fmt) 896 { 897 const char *array[4], *s; 898 const struct dentry *p; 899 int depth; 900 int i, n; 901 902 switch (fmt[1]) { 903 case '2': case '3': case '4': 904 depth = fmt[1] - '0'; 905 break; 906 default: 907 depth = 1; 908 } 909 910 rcu_read_lock(); 911 for (i = 0; i < depth; i++, d = p) { 912 if (check_pointer(&buf, end, d, spec)) { 913 rcu_read_unlock(); 914 return buf; 915 } 916 917 p = READ_ONCE(d->d_parent); 918 array[i] = READ_ONCE(d->d_name.name); 919 if (p == d) { 920 if (i) 921 array[i] = ""; 922 i++; 923 break; 924 } 925 } 926 s = array[--i]; 927 for (n = 0; n != spec.precision; n++, buf++) { 928 char c = *s++; 929 if (!c) { 930 if (!i) 931 break; 932 c = '/'; 933 s = array[--i]; 934 } 935 if (buf < end) 936 *buf = c; 937 } 938 rcu_read_unlock(); 939 return widen_string(buf, n, end, spec); 940 } 941 942 static noinline_for_stack 943 char *file_dentry_name(char *buf, char *end, const struct file *f, 944 struct printf_spec spec, const char *fmt) 945 { 946 if (check_pointer(&buf, end, f, spec)) 947 return buf; 948 949 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 950 } 951 #ifdef CONFIG_BLOCK 952 static noinline_for_stack 953 char *bdev_name(char *buf, char *end, struct block_device *bdev, 954 struct printf_spec spec, const char *fmt) 955 { 956 struct gendisk *hd; 957 958 if (check_pointer(&buf, end, bdev, spec)) 959 return buf; 960 961 hd = bdev->bd_disk; 962 buf = string(buf, end, hd->disk_name, spec); 963 if (bdev_is_partition(bdev)) { 964 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 965 if (buf < end) 966 *buf = 'p'; 967 buf++; 968 } 969 buf = number(buf, end, bdev_partno(bdev), spec); 970 } 971 return buf; 972 } 973 #endif 974 975 static noinline_for_stack 976 char *symbol_string(char *buf, char *end, void *ptr, 977 struct printf_spec spec, const char *fmt) 978 { 979 unsigned long value; 980 #ifdef CONFIG_KALLSYMS 981 char sym[KSYM_SYMBOL_LEN]; 982 #endif 983 984 if (fmt[1] == 'R') 985 ptr = __builtin_extract_return_addr(ptr); 986 value = (unsigned long)ptr; 987 988 #ifdef CONFIG_KALLSYMS 989 if (*fmt == 'B' && fmt[1] == 'b') 990 sprint_backtrace_build_id(sym, value); 991 else if (*fmt == 'B') 992 sprint_backtrace(sym, value); 993 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 994 sprint_symbol_build_id(sym, value); 995 else if (*fmt != 's') 996 sprint_symbol(sym, value); 997 else 998 sprint_symbol_no_offset(sym, value); 999 1000 return string_nocheck(buf, end, sym, spec); 1001 #else 1002 return special_hex_number(buf, end, value, sizeof(void *)); 1003 #endif 1004 } 1005 1006 static const struct printf_spec default_str_spec = { 1007 .field_width = -1, 1008 .precision = -1, 1009 }; 1010 1011 static const struct printf_spec default_flag_spec = { 1012 .base = 16, 1013 .precision = -1, 1014 .flags = SPECIAL | SMALL, 1015 }; 1016 1017 static const struct printf_spec default_dec_spec = { 1018 .base = 10, 1019 .precision = -1, 1020 }; 1021 1022 static const struct printf_spec default_dec02_spec = { 1023 .base = 10, 1024 .field_width = 2, 1025 .precision = -1, 1026 .flags = ZEROPAD, 1027 }; 1028 1029 static const struct printf_spec default_dec04_spec = { 1030 .base = 10, 1031 .field_width = 4, 1032 .precision = -1, 1033 .flags = ZEROPAD, 1034 }; 1035 1036 static noinline_for_stack 1037 char *hex_range(char *buf, char *end, u64 start_val, u64 end_val, 1038 struct printf_spec spec) 1039 { 1040 buf = number(buf, end, start_val, spec); 1041 if (start_val == end_val) 1042 return buf; 1043 1044 if (buf < end) 1045 *buf = '-'; 1046 ++buf; 1047 return number(buf, end, end_val, spec); 1048 } 1049 1050 static noinline_for_stack 1051 char *resource_string(char *buf, char *end, struct resource *res, 1052 struct printf_spec spec, const char *fmt) 1053 { 1054 #ifndef IO_RSRC_PRINTK_SIZE 1055 #define IO_RSRC_PRINTK_SIZE 6 1056 #endif 1057 1058 #ifndef MEM_RSRC_PRINTK_SIZE 1059 #define MEM_RSRC_PRINTK_SIZE 10 1060 #endif 1061 static const struct printf_spec io_spec = { 1062 .base = 16, 1063 .field_width = IO_RSRC_PRINTK_SIZE, 1064 .precision = -1, 1065 .flags = SPECIAL | SMALL | ZEROPAD, 1066 }; 1067 static const struct printf_spec mem_spec = { 1068 .base = 16, 1069 .field_width = MEM_RSRC_PRINTK_SIZE, 1070 .precision = -1, 1071 .flags = SPECIAL | SMALL | ZEROPAD, 1072 }; 1073 static const struct printf_spec bus_spec = { 1074 .base = 16, 1075 .field_width = 2, 1076 .precision = -1, 1077 .flags = SMALL | ZEROPAD, 1078 }; 1079 static const struct printf_spec str_spec = { 1080 .field_width = -1, 1081 .precision = 10, 1082 .flags = LEFT, 1083 }; 1084 1085 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1086 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1087 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1088 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1089 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1090 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1091 char sym[MAX(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1092 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1093 1094 char *p = sym, *pend = sym + sizeof(sym); 1095 int decode = (fmt[0] == 'R') ? 1 : 0; 1096 const struct printf_spec *specp; 1097 1098 if (check_pointer(&buf, end, res, spec)) 1099 return buf; 1100 1101 *p++ = '['; 1102 if (res->flags & IORESOURCE_IO) { 1103 p = string_nocheck(p, pend, "io ", str_spec); 1104 specp = &io_spec; 1105 } else if (res->flags & IORESOURCE_MEM) { 1106 p = string_nocheck(p, pend, "mem ", str_spec); 1107 specp = &mem_spec; 1108 } else if (res->flags & IORESOURCE_IRQ) { 1109 p = string_nocheck(p, pend, "irq ", str_spec); 1110 specp = &default_dec_spec; 1111 } else if (res->flags & IORESOURCE_DMA) { 1112 p = string_nocheck(p, pend, "dma ", str_spec); 1113 specp = &default_dec_spec; 1114 } else if (res->flags & IORESOURCE_BUS) { 1115 p = string_nocheck(p, pend, "bus ", str_spec); 1116 specp = &bus_spec; 1117 } else { 1118 p = string_nocheck(p, pend, "??? ", str_spec); 1119 specp = &mem_spec; 1120 decode = 0; 1121 } 1122 if (decode && res->flags & IORESOURCE_UNSET) { 1123 p = string_nocheck(p, pend, "size ", str_spec); 1124 p = number(p, pend, resource_size(res), *specp); 1125 } else { 1126 p = hex_range(p, pend, res->start, res->end, *specp); 1127 } 1128 if (decode) { 1129 if (res->flags & IORESOURCE_MEM_64) 1130 p = string_nocheck(p, pend, " 64bit", str_spec); 1131 if (res->flags & IORESOURCE_PREFETCH) 1132 p = string_nocheck(p, pend, " pref", str_spec); 1133 if (res->flags & IORESOURCE_WINDOW) 1134 p = string_nocheck(p, pend, " window", str_spec); 1135 if (res->flags & IORESOURCE_DISABLED) 1136 p = string_nocheck(p, pend, " disabled", str_spec); 1137 } else { 1138 p = string_nocheck(p, pend, " flags ", str_spec); 1139 p = number(p, pend, res->flags, default_flag_spec); 1140 } 1141 *p++ = ']'; 1142 *p = '\0'; 1143 1144 return string_nocheck(buf, end, sym, spec); 1145 } 1146 1147 static noinline_for_stack 1148 char *range_string(char *buf, char *end, const struct range *range, 1149 struct printf_spec spec, const char *fmt) 1150 { 1151 char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")]; 1152 char *p = sym, *pend = sym + sizeof(sym); 1153 1154 struct printf_spec range_spec = { 1155 .field_width = 2 + 2 * sizeof(range->start), /* 0x + 2 * 8 */ 1156 .flags = SPECIAL | SMALL | ZEROPAD, 1157 .base = 16, 1158 .precision = -1, 1159 }; 1160 1161 if (check_pointer(&buf, end, range, spec)) 1162 return buf; 1163 1164 p = string_nocheck(p, pend, "[range ", default_str_spec); 1165 p = hex_range(p, pend, range->start, range->end, range_spec); 1166 *p++ = ']'; 1167 *p = '\0'; 1168 1169 return string_nocheck(buf, end, sym, spec); 1170 } 1171 1172 static noinline_for_stack 1173 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1174 const char *fmt) 1175 { 1176 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1177 negative value, fallback to the default */ 1178 char separator; 1179 1180 if (spec.field_width == 0) 1181 /* nothing to print */ 1182 return buf; 1183 1184 if (check_pointer(&buf, end, addr, spec)) 1185 return buf; 1186 1187 switch (fmt[1]) { 1188 case 'C': 1189 separator = ':'; 1190 break; 1191 case 'D': 1192 separator = '-'; 1193 break; 1194 case 'N': 1195 separator = 0; 1196 break; 1197 default: 1198 separator = ' '; 1199 break; 1200 } 1201 1202 if (spec.field_width > 0) 1203 len = min_t(int, spec.field_width, 64); 1204 1205 for (i = 0; i < len; ++i) { 1206 if (buf < end) 1207 *buf = hex_asc_hi(addr[i]); 1208 ++buf; 1209 if (buf < end) 1210 *buf = hex_asc_lo(addr[i]); 1211 ++buf; 1212 1213 if (separator && i != len - 1) { 1214 if (buf < end) 1215 *buf = separator; 1216 ++buf; 1217 } 1218 } 1219 1220 return buf; 1221 } 1222 1223 static noinline_for_stack 1224 char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, 1225 struct printf_spec spec, const char *fmt) 1226 { 1227 const int CHUNKSZ = 32; 1228 int nr_bits = max_t(int, spec.field_width, 0); 1229 int i, chunksz; 1230 bool first = true; 1231 1232 if (check_pointer(&buf, end, bitmap, spec)) 1233 return buf; 1234 1235 /* reused to print numbers */ 1236 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1237 1238 chunksz = nr_bits & (CHUNKSZ - 1); 1239 if (chunksz == 0) 1240 chunksz = CHUNKSZ; 1241 1242 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1243 for (; i >= 0; i -= CHUNKSZ) { 1244 u32 chunkmask, val; 1245 int word, bit; 1246 1247 chunkmask = ((1ULL << chunksz) - 1); 1248 word = i / BITS_PER_LONG; 1249 bit = i % BITS_PER_LONG; 1250 val = (bitmap[word] >> bit) & chunkmask; 1251 1252 if (!first) { 1253 if (buf < end) 1254 *buf = ','; 1255 buf++; 1256 } 1257 first = false; 1258 1259 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1260 buf = number(buf, end, val, spec); 1261 1262 chunksz = CHUNKSZ; 1263 } 1264 return buf; 1265 } 1266 1267 static noinline_for_stack 1268 char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, 1269 struct printf_spec spec, const char *fmt) 1270 { 1271 int nr_bits = max_t(int, spec.field_width, 0); 1272 bool first = true; 1273 int rbot, rtop; 1274 1275 if (check_pointer(&buf, end, bitmap, spec)) 1276 return buf; 1277 1278 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1279 if (!first) { 1280 if (buf < end) 1281 *buf = ','; 1282 buf++; 1283 } 1284 first = false; 1285 1286 buf = number(buf, end, rbot, default_dec_spec); 1287 if (rtop == rbot + 1) 1288 continue; 1289 1290 if (buf < end) 1291 *buf = '-'; 1292 buf = number(++buf, end, rtop - 1, default_dec_spec); 1293 } 1294 return buf; 1295 } 1296 1297 static noinline_for_stack 1298 char *mac_address_string(char *buf, char *end, u8 *addr, 1299 struct printf_spec spec, const char *fmt) 1300 { 1301 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1302 char *p = mac_addr; 1303 int i; 1304 char separator; 1305 bool reversed = false; 1306 1307 if (check_pointer(&buf, end, addr, spec)) 1308 return buf; 1309 1310 switch (fmt[1]) { 1311 case 'F': 1312 separator = '-'; 1313 break; 1314 1315 case 'R': 1316 reversed = true; 1317 fallthrough; 1318 1319 default: 1320 separator = ':'; 1321 break; 1322 } 1323 1324 for (i = 0; i < 6; i++) { 1325 if (reversed) 1326 p = hex_byte_pack(p, addr[5 - i]); 1327 else 1328 p = hex_byte_pack(p, addr[i]); 1329 1330 if (fmt[0] == 'M' && i != 5) 1331 *p++ = separator; 1332 } 1333 *p = '\0'; 1334 1335 return string_nocheck(buf, end, mac_addr, spec); 1336 } 1337 1338 static noinline_for_stack 1339 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1340 { 1341 int i; 1342 bool leading_zeros = (fmt[0] == 'i'); 1343 int index; 1344 int step; 1345 1346 switch (fmt[2]) { 1347 case 'h': 1348 #ifdef __BIG_ENDIAN 1349 index = 0; 1350 step = 1; 1351 #else 1352 index = 3; 1353 step = -1; 1354 #endif 1355 break; 1356 case 'l': 1357 index = 3; 1358 step = -1; 1359 break; 1360 case 'n': 1361 case 'b': 1362 default: 1363 index = 0; 1364 step = 1; 1365 break; 1366 } 1367 for (i = 0; i < 4; i++) { 1368 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1369 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1370 if (leading_zeros) { 1371 if (digits < 3) 1372 *p++ = '0'; 1373 if (digits < 2) 1374 *p++ = '0'; 1375 } 1376 /* reverse the digits in the quad */ 1377 while (digits--) 1378 *p++ = temp[digits]; 1379 if (i < 3) 1380 *p++ = '.'; 1381 index += step; 1382 } 1383 *p = '\0'; 1384 1385 return p; 1386 } 1387 1388 static noinline_for_stack 1389 char *ip6_compressed_string(char *p, const char *addr) 1390 { 1391 int i, j, range; 1392 unsigned char zerolength[8]; 1393 int longest = 1; 1394 int colonpos = -1; 1395 u16 word; 1396 u8 hi, lo; 1397 bool needcolon = false; 1398 bool useIPv4; 1399 struct in6_addr in6; 1400 1401 memcpy(&in6, addr, sizeof(struct in6_addr)); 1402 1403 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1404 1405 memset(zerolength, 0, sizeof(zerolength)); 1406 1407 if (useIPv4) 1408 range = 6; 1409 else 1410 range = 8; 1411 1412 /* find position of longest 0 run */ 1413 for (i = 0; i < range; i++) { 1414 for (j = i; j < range; j++) { 1415 if (in6.s6_addr16[j] != 0) 1416 break; 1417 zerolength[i]++; 1418 } 1419 } 1420 for (i = 0; i < range; i++) { 1421 if (zerolength[i] > longest) { 1422 longest = zerolength[i]; 1423 colonpos = i; 1424 } 1425 } 1426 if (longest == 1) /* don't compress a single 0 */ 1427 colonpos = -1; 1428 1429 /* emit address */ 1430 for (i = 0; i < range; i++) { 1431 if (i == colonpos) { 1432 if (needcolon || i == 0) 1433 *p++ = ':'; 1434 *p++ = ':'; 1435 needcolon = false; 1436 i += longest - 1; 1437 continue; 1438 } 1439 if (needcolon) { 1440 *p++ = ':'; 1441 needcolon = false; 1442 } 1443 /* hex u16 without leading 0s */ 1444 word = ntohs(in6.s6_addr16[i]); 1445 hi = word >> 8; 1446 lo = word & 0xff; 1447 if (hi) { 1448 if (hi > 0x0f) 1449 p = hex_byte_pack(p, hi); 1450 else 1451 *p++ = hex_asc_lo(hi); 1452 p = hex_byte_pack(p, lo); 1453 } 1454 else if (lo > 0x0f) 1455 p = hex_byte_pack(p, lo); 1456 else 1457 *p++ = hex_asc_lo(lo); 1458 needcolon = true; 1459 } 1460 1461 if (useIPv4) { 1462 if (needcolon) 1463 *p++ = ':'; 1464 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1465 } 1466 *p = '\0'; 1467 1468 return p; 1469 } 1470 1471 static noinline_for_stack 1472 char *ip6_string(char *p, const char *addr, const char *fmt) 1473 { 1474 int i; 1475 1476 for (i = 0; i < 8; i++) { 1477 p = hex_byte_pack(p, *addr++); 1478 p = hex_byte_pack(p, *addr++); 1479 if (fmt[0] == 'I' && i != 7) 1480 *p++ = ':'; 1481 } 1482 *p = '\0'; 1483 1484 return p; 1485 } 1486 1487 static noinline_for_stack 1488 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1489 struct printf_spec spec, const char *fmt) 1490 { 1491 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1492 1493 if (fmt[0] == 'I' && fmt[2] == 'c') 1494 ip6_compressed_string(ip6_addr, addr); 1495 else 1496 ip6_string(ip6_addr, addr, fmt); 1497 1498 return string_nocheck(buf, end, ip6_addr, spec); 1499 } 1500 1501 static noinline_for_stack 1502 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1503 struct printf_spec spec, const char *fmt) 1504 { 1505 char ip4_addr[sizeof("255.255.255.255")]; 1506 1507 ip4_string(ip4_addr, addr, fmt); 1508 1509 return string_nocheck(buf, end, ip4_addr, spec); 1510 } 1511 1512 static noinline_for_stack 1513 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1514 struct printf_spec spec, const char *fmt) 1515 { 1516 bool have_p = false, have_s = false, have_f = false, have_c = false; 1517 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1518 sizeof(":12345") + sizeof("/123456789") + 1519 sizeof("%1234567890")]; 1520 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1521 const u8 *addr = (const u8 *) &sa->sin6_addr; 1522 char fmt6[2] = { fmt[0], '6' }; 1523 u8 off = 0; 1524 1525 fmt++; 1526 while (isalpha(*++fmt)) { 1527 switch (*fmt) { 1528 case 'p': 1529 have_p = true; 1530 break; 1531 case 'f': 1532 have_f = true; 1533 break; 1534 case 's': 1535 have_s = true; 1536 break; 1537 case 'c': 1538 have_c = true; 1539 break; 1540 } 1541 } 1542 1543 if (have_p || have_s || have_f) { 1544 *p = '['; 1545 off = 1; 1546 } 1547 1548 if (fmt6[0] == 'I' && have_c) 1549 p = ip6_compressed_string(ip6_addr + off, addr); 1550 else 1551 p = ip6_string(ip6_addr + off, addr, fmt6); 1552 1553 if (have_p || have_s || have_f) 1554 *p++ = ']'; 1555 1556 if (have_p) { 1557 *p++ = ':'; 1558 p = number(p, pend, ntohs(sa->sin6_port), spec); 1559 } 1560 if (have_f) { 1561 *p++ = '/'; 1562 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1563 IPV6_FLOWINFO_MASK), spec); 1564 } 1565 if (have_s) { 1566 *p++ = '%'; 1567 p = number(p, pend, sa->sin6_scope_id, spec); 1568 } 1569 *p = '\0'; 1570 1571 return string_nocheck(buf, end, ip6_addr, spec); 1572 } 1573 1574 static noinline_for_stack 1575 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1576 struct printf_spec spec, const char *fmt) 1577 { 1578 bool have_p = false; 1579 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1580 char *pend = ip4_addr + sizeof(ip4_addr); 1581 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1582 char fmt4[3] = { fmt[0], '4', 0 }; 1583 1584 fmt++; 1585 while (isalpha(*++fmt)) { 1586 switch (*fmt) { 1587 case 'p': 1588 have_p = true; 1589 break; 1590 case 'h': 1591 case 'l': 1592 case 'n': 1593 case 'b': 1594 fmt4[2] = *fmt; 1595 break; 1596 } 1597 } 1598 1599 p = ip4_string(ip4_addr, addr, fmt4); 1600 if (have_p) { 1601 *p++ = ':'; 1602 p = number(p, pend, ntohs(sa->sin_port), spec); 1603 } 1604 *p = '\0'; 1605 1606 return string_nocheck(buf, end, ip4_addr, spec); 1607 } 1608 1609 static noinline_for_stack 1610 char *ip_addr_string(char *buf, char *end, const void *ptr, 1611 struct printf_spec spec, const char *fmt) 1612 { 1613 char *err_fmt_msg; 1614 1615 if (check_pointer(&buf, end, ptr, spec)) 1616 return buf; 1617 1618 switch (fmt[1]) { 1619 case '6': 1620 return ip6_addr_string(buf, end, ptr, spec, fmt); 1621 case '4': 1622 return ip4_addr_string(buf, end, ptr, spec, fmt); 1623 case 'S': { 1624 const union { 1625 struct sockaddr raw; 1626 struct sockaddr_in v4; 1627 struct sockaddr_in6 v6; 1628 } *sa = ptr; 1629 1630 switch (sa->raw.sa_family) { 1631 case AF_INET: 1632 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1633 case AF_INET6: 1634 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1635 default: 1636 return error_string(buf, end, "(einval)", spec); 1637 }} 1638 } 1639 1640 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1641 return error_string(buf, end, err_fmt_msg, spec); 1642 } 1643 1644 static noinline_for_stack 1645 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1646 const char *fmt) 1647 { 1648 bool found = true; 1649 int count = 1; 1650 unsigned int flags = 0; 1651 int len; 1652 1653 if (spec.field_width == 0) 1654 return buf; /* nothing to print */ 1655 1656 if (check_pointer(&buf, end, addr, spec)) 1657 return buf; 1658 1659 do { 1660 switch (fmt[count++]) { 1661 case 'a': 1662 flags |= ESCAPE_ANY; 1663 break; 1664 case 'c': 1665 flags |= ESCAPE_SPECIAL; 1666 break; 1667 case 'h': 1668 flags |= ESCAPE_HEX; 1669 break; 1670 case 'n': 1671 flags |= ESCAPE_NULL; 1672 break; 1673 case 'o': 1674 flags |= ESCAPE_OCTAL; 1675 break; 1676 case 'p': 1677 flags |= ESCAPE_NP; 1678 break; 1679 case 's': 1680 flags |= ESCAPE_SPACE; 1681 break; 1682 default: 1683 found = false; 1684 break; 1685 } 1686 } while (found); 1687 1688 if (!flags) 1689 flags = ESCAPE_ANY_NP; 1690 1691 len = spec.field_width < 0 ? 1 : spec.field_width; 1692 1693 /* 1694 * string_escape_mem() writes as many characters as it can to 1695 * the given buffer, and returns the total size of the output 1696 * had the buffer been big enough. 1697 */ 1698 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1699 1700 return buf; 1701 } 1702 1703 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1704 struct printf_spec spec, const char *fmt) 1705 { 1706 va_list va; 1707 1708 if (check_pointer(&buf, end, va_fmt, spec)) 1709 return buf; 1710 1711 va_copy(va, *va_fmt->va); 1712 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1713 va_end(va); 1714 1715 return buf; 1716 } 1717 1718 static noinline_for_stack 1719 char *uuid_string(char *buf, char *end, const u8 *addr, 1720 struct printf_spec spec, const char *fmt) 1721 { 1722 char uuid[UUID_STRING_LEN + 1]; 1723 char *p = uuid; 1724 int i; 1725 const u8 *index = uuid_index; 1726 bool uc = false; 1727 1728 if (check_pointer(&buf, end, addr, spec)) 1729 return buf; 1730 1731 switch (*(++fmt)) { 1732 case 'L': 1733 uc = true; 1734 fallthrough; 1735 case 'l': 1736 index = guid_index; 1737 break; 1738 case 'B': 1739 uc = true; 1740 break; 1741 } 1742 1743 for (i = 0; i < 16; i++) { 1744 if (uc) 1745 p = hex_byte_pack_upper(p, addr[index[i]]); 1746 else 1747 p = hex_byte_pack(p, addr[index[i]]); 1748 switch (i) { 1749 case 3: 1750 case 5: 1751 case 7: 1752 case 9: 1753 *p++ = '-'; 1754 break; 1755 } 1756 } 1757 1758 *p = 0; 1759 1760 return string_nocheck(buf, end, uuid, spec); 1761 } 1762 1763 static noinline_for_stack 1764 char *netdev_bits(char *buf, char *end, const void *addr, 1765 struct printf_spec spec, const char *fmt) 1766 { 1767 unsigned long long num; 1768 int size; 1769 1770 if (check_pointer(&buf, end, addr, spec)) 1771 return buf; 1772 1773 switch (fmt[1]) { 1774 case 'F': 1775 num = *(const netdev_features_t *)addr; 1776 size = sizeof(netdev_features_t); 1777 break; 1778 default: 1779 return error_string(buf, end, "(%pN?)", spec); 1780 } 1781 1782 return special_hex_number(buf, end, num, size); 1783 } 1784 1785 static noinline_for_stack 1786 char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1787 struct printf_spec spec, const char *fmt) 1788 { 1789 char output[sizeof("0123 little-endian (0x01234567)")]; 1790 char *p = output; 1791 unsigned int i; 1792 u32 orig, val; 1793 1794 if (fmt[1] != 'c' || fmt[2] != 'c') 1795 return error_string(buf, end, "(%p4?)", spec); 1796 1797 if (check_pointer(&buf, end, fourcc, spec)) 1798 return buf; 1799 1800 orig = get_unaligned(fourcc); 1801 val = orig & ~BIT(31); 1802 1803 for (i = 0; i < sizeof(u32); i++) { 1804 unsigned char c = val >> (i * 8); 1805 1806 /* Print non-control ASCII characters as-is, dot otherwise */ 1807 *p++ = isascii(c) && isprint(c) ? c : '.'; 1808 } 1809 1810 *p++ = ' '; 1811 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1812 p += strlen(p); 1813 1814 *p++ = ' '; 1815 *p++ = '('; 1816 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1817 *p++ = ')'; 1818 *p = '\0'; 1819 1820 return string(buf, end, output, spec); 1821 } 1822 1823 static noinline_for_stack 1824 char *address_val(char *buf, char *end, const void *addr, 1825 struct printf_spec spec, const char *fmt) 1826 { 1827 unsigned long long num; 1828 int size; 1829 1830 if (check_pointer(&buf, end, addr, spec)) 1831 return buf; 1832 1833 switch (fmt[1]) { 1834 case 'd': 1835 num = *(const dma_addr_t *)addr; 1836 size = sizeof(dma_addr_t); 1837 break; 1838 case 'p': 1839 default: 1840 num = *(const phys_addr_t *)addr; 1841 size = sizeof(phys_addr_t); 1842 break; 1843 } 1844 1845 return special_hex_number(buf, end, num, size); 1846 } 1847 1848 static noinline_for_stack 1849 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1850 { 1851 int year = tm->tm_year + (r ? 0 : 1900); 1852 int mon = tm->tm_mon + (r ? 0 : 1); 1853 1854 buf = number(buf, end, year, default_dec04_spec); 1855 if (buf < end) 1856 *buf = '-'; 1857 buf++; 1858 1859 buf = number(buf, end, mon, default_dec02_spec); 1860 if (buf < end) 1861 *buf = '-'; 1862 buf++; 1863 1864 return number(buf, end, tm->tm_mday, default_dec02_spec); 1865 } 1866 1867 static noinline_for_stack 1868 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1869 { 1870 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1871 if (buf < end) 1872 *buf = ':'; 1873 buf++; 1874 1875 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1876 if (buf < end) 1877 *buf = ':'; 1878 buf++; 1879 1880 return number(buf, end, tm->tm_sec, default_dec02_spec); 1881 } 1882 1883 static noinline_for_stack 1884 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1885 struct printf_spec spec, const char *fmt) 1886 { 1887 bool have_t = true, have_d = true; 1888 bool raw = false, iso8601_separator = true; 1889 bool found = true; 1890 int count = 2; 1891 1892 if (check_pointer(&buf, end, tm, spec)) 1893 return buf; 1894 1895 switch (fmt[count]) { 1896 case 'd': 1897 have_t = false; 1898 count++; 1899 break; 1900 case 't': 1901 have_d = false; 1902 count++; 1903 break; 1904 } 1905 1906 do { 1907 switch (fmt[count++]) { 1908 case 'r': 1909 raw = true; 1910 break; 1911 case 's': 1912 iso8601_separator = false; 1913 break; 1914 default: 1915 found = false; 1916 break; 1917 } 1918 } while (found); 1919 1920 if (have_d) 1921 buf = date_str(buf, end, tm, raw); 1922 if (have_d && have_t) { 1923 if (buf < end) 1924 *buf = iso8601_separator ? 'T' : ' '; 1925 buf++; 1926 } 1927 if (have_t) 1928 buf = time_str(buf, end, tm, raw); 1929 1930 return buf; 1931 } 1932 1933 static noinline_for_stack 1934 char *time64_str(char *buf, char *end, const time64_t time, 1935 struct printf_spec spec, const char *fmt) 1936 { 1937 struct rtc_time rtc_time; 1938 struct tm tm; 1939 1940 time64_to_tm(time, 0, &tm); 1941 1942 rtc_time.tm_sec = tm.tm_sec; 1943 rtc_time.tm_min = tm.tm_min; 1944 rtc_time.tm_hour = tm.tm_hour; 1945 rtc_time.tm_mday = tm.tm_mday; 1946 rtc_time.tm_mon = tm.tm_mon; 1947 rtc_time.tm_year = tm.tm_year; 1948 rtc_time.tm_wday = tm.tm_wday; 1949 rtc_time.tm_yday = tm.tm_yday; 1950 1951 rtc_time.tm_isdst = 0; 1952 1953 return rtc_str(buf, end, &rtc_time, spec, fmt); 1954 } 1955 1956 static noinline_for_stack 1957 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1958 const char *fmt) 1959 { 1960 switch (fmt[1]) { 1961 case 'R': 1962 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1963 case 'T': 1964 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 1965 default: 1966 return error_string(buf, end, "(%pt?)", spec); 1967 } 1968 } 1969 1970 static noinline_for_stack 1971 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1972 const char *fmt) 1973 { 1974 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1975 return error_string(buf, end, "(%pC?)", spec); 1976 1977 if (check_pointer(&buf, end, clk, spec)) 1978 return buf; 1979 1980 switch (fmt[1]) { 1981 case 'n': 1982 default: 1983 #ifdef CONFIG_COMMON_CLK 1984 return string(buf, end, __clk_get_name(clk), spec); 1985 #else 1986 return ptr_to_id(buf, end, clk, spec); 1987 #endif 1988 } 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 /* Used for Rust formatting ('%pA'). */ 2296 char *rust_fmt_argument(char *buf, char *end, void *ptr); 2297 2298 /* 2299 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2300 * by an extra set of alphanumeric characters that are extended format 2301 * specifiers. 2302 * 2303 * Please update scripts/checkpatch.pl when adding/removing conversion 2304 * characters. (Search for "check for vsprintf extension"). 2305 * 2306 * Right now we handle: 2307 * 2308 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2309 * - 's' For symbolic direct pointers (or function descriptors) without offset 2310 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2311 * - 'S[R]b' as above with module build ID (for use in backtraces) 2312 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2313 * %ps and %pS. Be careful when re-using these specifiers. 2314 * - 'B' For backtraced symbolic direct pointers with offset 2315 * - 'Bb' as above with module build ID (for use in backtraces) 2316 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2317 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2318 * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] 2319 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2320 * width which must be explicitly specified either as part of the 2321 * format string '%32b[l]' or through '%*b[l]', [l] selects 2322 * range-list format instead of hex format 2323 * - 'M' For a 6-byte MAC address, it prints the address in the 2324 * usual colon-separated hex notation 2325 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2326 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2327 * with a dash-separated hex notation 2328 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2329 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2330 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2331 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2332 * [S][pfs] 2333 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2334 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2335 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2336 * IPv6 omits the colons (01020304...0f) 2337 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2338 * [S][pfs] 2339 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2340 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2341 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2342 * - 'I[6S]c' for IPv6 addresses printed as specified by 2343 * https://tools.ietf.org/html/rfc5952 2344 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2345 * of the following flags (see string_escape_mem() for the 2346 * details): 2347 * a - ESCAPE_ANY 2348 * c - ESCAPE_SPECIAL 2349 * h - ESCAPE_HEX 2350 * n - ESCAPE_NULL 2351 * o - ESCAPE_OCTAL 2352 * p - ESCAPE_NP 2353 * s - ESCAPE_SPACE 2354 * By default ESCAPE_ANY_NP is used. 2355 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2356 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2357 * Options for %pU are: 2358 * b big endian lower case hex (default) 2359 * B big endian UPPER case hex 2360 * l little endian lower case hex 2361 * L little endian UPPER case hex 2362 * big endian output byte order is: 2363 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2364 * little endian output byte order is: 2365 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2366 * - 'V' For a struct va_format which contains a format string * and va_list *, 2367 * call vsnprintf(->format, *->va_list). 2368 * Implements a "recursive vsnprintf". 2369 * Do not use this feature without some mechanism to verify the 2370 * correctness of the format string and va_list arguments. 2371 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2372 * Use only for procfs, sysfs and similar files, not printk(); please 2373 * read the documentation (path below) first. 2374 * - 'NF' For a netdev_features_t 2375 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2376 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2377 * a certain separator (' ' by default): 2378 * C colon 2379 * D dash 2380 * N no separator 2381 * The maximum supported length is 64 bytes of the input. Consider 2382 * to use print_hex_dump() for the larger input. 2383 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2384 * (default assumed to be phys_addr_t, passed by reference) 2385 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2386 * - 'D[234]' Same as 'd' but for a struct file 2387 * - 'g' For block_device name (gendisk + partition number) 2388 * - 't[RT][dt][r][s]' For time and date as represented by: 2389 * R struct rtc_time 2390 * T time64_t 2391 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2392 * (legacy clock framework) of the clock 2393 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2394 * (legacy clock framework) of the clock 2395 * - 'G' For flags to be printed as a collection of symbolic strings that would 2396 * construct the specific value. Supported flags given by option: 2397 * p page flags (see struct page) given as pointer to unsigned long 2398 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2399 * v vma flags (VM_*) given as pointer to unsigned long 2400 * - 'OF[fnpPcCF]' For a device tree object 2401 * Without any optional arguments prints the full_name 2402 * f device node full_name 2403 * n device node name 2404 * p device node phandle 2405 * P device node path spec (name + @unit) 2406 * F device node flags 2407 * c major compatible string 2408 * C full compatible string 2409 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2410 * Without an option prints the full name of the node 2411 * f full name 2412 * P node name, including a possible unit address 2413 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2414 * Please read the documentation (path below) before using! 2415 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2416 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2417 * or user (u) memory to probe, and: 2418 * s a string, equivalent to "%s" on direct vsnprintf() use 2419 * 2420 * ** When making changes please also update: 2421 * Documentation/core-api/printk-formats.rst 2422 * 2423 * Note: The default behaviour (unadorned %p) is to hash the address, 2424 * rendering it useful as a unique identifier. 2425 * 2426 * There is also a '%pA' format specifier, but it is only intended to be used 2427 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2428 * See rust/kernel/print.rs for details. 2429 */ 2430 static noinline_for_stack 2431 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2432 struct printf_spec spec) 2433 { 2434 switch (*fmt) { 2435 case 'S': 2436 case 's': 2437 ptr = dereference_symbol_descriptor(ptr); 2438 fallthrough; 2439 case 'B': 2440 return symbol_string(buf, end, ptr, spec, fmt); 2441 case 'R': 2442 case 'r': 2443 return resource_or_range(fmt, buf, end, ptr, spec); 2444 case 'h': 2445 return hex_string(buf, end, ptr, spec, fmt); 2446 case 'b': 2447 switch (fmt[1]) { 2448 case 'l': 2449 return bitmap_list_string(buf, end, ptr, spec, fmt); 2450 default: 2451 return bitmap_string(buf, end, ptr, spec, fmt); 2452 } 2453 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2454 case 'm': /* Contiguous: 000102030405 */ 2455 /* [mM]F (FDDI) */ 2456 /* [mM]R (Reverse order; Bluetooth) */ 2457 return mac_address_string(buf, end, ptr, spec, fmt); 2458 case 'I': /* Formatted IP supported 2459 * 4: 1.2.3.4 2460 * 6: 0001:0203:...:0708 2461 * 6c: 1::708 or 1::1.2.3.4 2462 */ 2463 case 'i': /* Contiguous: 2464 * 4: 001.002.003.004 2465 * 6: 000102...0f 2466 */ 2467 return ip_addr_string(buf, end, ptr, spec, fmt); 2468 case 'E': 2469 return escaped_string(buf, end, ptr, spec, fmt); 2470 case 'U': 2471 return uuid_string(buf, end, ptr, spec, fmt); 2472 case 'V': 2473 return va_format(buf, end, ptr, spec, fmt); 2474 case 'K': 2475 return restricted_pointer(buf, end, ptr, spec); 2476 case 'N': 2477 return netdev_bits(buf, end, ptr, spec, fmt); 2478 case '4': 2479 return fourcc_string(buf, end, ptr, spec, fmt); 2480 case 'a': 2481 return address_val(buf, end, ptr, spec, fmt); 2482 case 'd': 2483 return dentry_name(buf, end, ptr, spec, fmt); 2484 case 't': 2485 return time_and_date(buf, end, ptr, spec, fmt); 2486 case 'C': 2487 return clock(buf, end, ptr, spec, fmt); 2488 case 'D': 2489 return file_dentry_name(buf, end, ptr, spec, fmt); 2490 #ifdef CONFIG_BLOCK 2491 case 'g': 2492 return bdev_name(buf, end, ptr, spec, fmt); 2493 #endif 2494 2495 case 'G': 2496 return flags_string(buf, end, ptr, spec, fmt); 2497 case 'O': 2498 return device_node_string(buf, end, ptr, spec, fmt + 1); 2499 case 'f': 2500 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2501 case 'A': 2502 if (!IS_ENABLED(CONFIG_RUST)) { 2503 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2504 return error_string(buf, end, "(%pA?)", spec); 2505 } 2506 return rust_fmt_argument(buf, end, ptr); 2507 case 'x': 2508 return pointer_string(buf, end, ptr, spec); 2509 case 'e': 2510 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2511 if (!IS_ERR(ptr)) 2512 return default_pointer(buf, end, ptr, spec); 2513 return err_ptr(buf, end, ptr, spec); 2514 case 'u': 2515 case 'k': 2516 switch (fmt[1]) { 2517 case 's': 2518 return string(buf, end, ptr, spec); 2519 default: 2520 return error_string(buf, end, "(einval)", spec); 2521 } 2522 default: 2523 return default_pointer(buf, end, ptr, spec); 2524 } 2525 } 2526 2527 /* 2528 * Helper function to decode printf style format. 2529 * Each call decode a token from the format and return the 2530 * number of characters read (or likely the delta where it wants 2531 * to go on the next call). 2532 * The decoded token is returned through the parameters 2533 * 2534 * 'h', 'l', or 'L' for integer fields 2535 * 'z' support added 23/7/1999 S.H. 2536 * 'z' changed to 'Z' --davidm 1/25/99 2537 * 'Z' changed to 'z' --adobriyan 2017-01-25 2538 * 't' added for ptrdiff_t 2539 * 2540 * @fmt: the format string 2541 * @type of the token returned 2542 * @flags: various flags such as +, -, # tokens.. 2543 * @field_width: overwritten width 2544 * @base: base of the number (octal, hex, ...) 2545 * @precision: precision of a number 2546 * @qualifier: qualifier of a number (long, size_t, ...) 2547 */ 2548 static noinline_for_stack 2549 int format_decode(const char *fmt, struct printf_spec *spec) 2550 { 2551 const char *start = fmt; 2552 char qualifier; 2553 2554 /* we finished early by reading the field width */ 2555 if (spec->type == FORMAT_TYPE_WIDTH) { 2556 if (spec->field_width < 0) { 2557 spec->field_width = -spec->field_width; 2558 spec->flags |= LEFT; 2559 } 2560 spec->type = FORMAT_TYPE_NONE; 2561 goto precision; 2562 } 2563 2564 /* we finished early by reading the precision */ 2565 if (spec->type == FORMAT_TYPE_PRECISION) { 2566 if (spec->precision < 0) 2567 spec->precision = 0; 2568 2569 spec->type = FORMAT_TYPE_NONE; 2570 goto qualifier; 2571 } 2572 2573 /* By default */ 2574 spec->type = FORMAT_TYPE_NONE; 2575 2576 for (; *fmt ; ++fmt) { 2577 if (*fmt == '%') 2578 break; 2579 } 2580 2581 /* Return the current non-format string */ 2582 if (fmt != start || !*fmt) 2583 return fmt - start; 2584 2585 /* Process flags */ 2586 spec->flags = 0; 2587 2588 while (1) { /* this also skips first '%' */ 2589 bool found = true; 2590 2591 ++fmt; 2592 2593 switch (*fmt) { 2594 case '-': spec->flags |= LEFT; break; 2595 case '+': spec->flags |= PLUS; break; 2596 case ' ': spec->flags |= SPACE; break; 2597 case '#': spec->flags |= SPECIAL; break; 2598 case '0': spec->flags |= ZEROPAD; break; 2599 default: found = false; 2600 } 2601 2602 if (!found) 2603 break; 2604 } 2605 2606 /* get field width */ 2607 spec->field_width = -1; 2608 2609 if (isdigit(*fmt)) 2610 spec->field_width = skip_atoi(&fmt); 2611 else if (*fmt == '*') { 2612 /* it's the next argument */ 2613 spec->type = FORMAT_TYPE_WIDTH; 2614 return ++fmt - start; 2615 } 2616 2617 precision: 2618 /* get the precision */ 2619 spec->precision = -1; 2620 if (*fmt == '.') { 2621 ++fmt; 2622 if (isdigit(*fmt)) { 2623 spec->precision = skip_atoi(&fmt); 2624 if (spec->precision < 0) 2625 spec->precision = 0; 2626 } else if (*fmt == '*') { 2627 /* it's the next argument */ 2628 spec->type = FORMAT_TYPE_PRECISION; 2629 return ++fmt - start; 2630 } 2631 } 2632 2633 qualifier: 2634 /* get the conversion qualifier */ 2635 qualifier = 0; 2636 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2637 *fmt == 'z' || *fmt == 't') { 2638 qualifier = *fmt++; 2639 if (unlikely(qualifier == *fmt)) { 2640 if (qualifier == 'l') { 2641 qualifier = 'L'; 2642 ++fmt; 2643 } else if (qualifier == 'h') { 2644 qualifier = 'H'; 2645 ++fmt; 2646 } 2647 } 2648 } 2649 2650 /* default base */ 2651 spec->base = 10; 2652 switch (*fmt) { 2653 case 'c': 2654 spec->type = FORMAT_TYPE_CHAR; 2655 return ++fmt - start; 2656 2657 case 's': 2658 spec->type = FORMAT_TYPE_STR; 2659 return ++fmt - start; 2660 2661 case 'p': 2662 spec->type = FORMAT_TYPE_PTR; 2663 return ++fmt - start; 2664 2665 case '%': 2666 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2667 return ++fmt - start; 2668 2669 /* integer number formats - set up the flags and "break" */ 2670 case 'o': 2671 spec->base = 8; 2672 break; 2673 2674 case 'x': 2675 spec->flags |= SMALL; 2676 fallthrough; 2677 2678 case 'X': 2679 spec->base = 16; 2680 break; 2681 2682 case 'd': 2683 case 'i': 2684 spec->flags |= SIGN; 2685 break; 2686 case 'u': 2687 break; 2688 2689 case 'n': 2690 /* 2691 * Since %n poses a greater security risk than 2692 * utility, treat it as any other invalid or 2693 * unsupported format specifier. 2694 */ 2695 fallthrough; 2696 2697 default: 2698 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2699 spec->type = FORMAT_TYPE_INVALID; 2700 return fmt - start; 2701 } 2702 2703 if (qualifier == 'L') 2704 spec->type = FORMAT_TYPE_SIZE(long long); 2705 else if (qualifier == 'l') { 2706 spec->type = FORMAT_TYPE_SIZE(long); 2707 } else if (qualifier == 'z') { 2708 spec->type = FORMAT_TYPE_SIZE(size_t); 2709 } else if (qualifier == 't') { 2710 spec->type = FORMAT_TYPE_SIZE(ptrdiff_t); 2711 } else if (qualifier == 'H') { 2712 spec->type = FORMAT_TYPE_SIZE(char); 2713 } else if (qualifier == 'h') { 2714 spec->type = FORMAT_TYPE_SIZE(short); 2715 } else { 2716 spec->type = FORMAT_TYPE_SIZE(int); 2717 } 2718 2719 return ++fmt - start; 2720 } 2721 2722 static void 2723 set_field_width(struct printf_spec *spec, int width) 2724 { 2725 spec->field_width = width; 2726 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2727 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2728 } 2729 } 2730 2731 static void 2732 set_precision(struct printf_spec *spec, int prec) 2733 { 2734 spec->precision = prec; 2735 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2736 spec->precision = clamp(prec, 0, PRECISION_MAX); 2737 } 2738 } 2739 2740 /* 2741 * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate 2742 * as necessary and deal with signedness. 2743 * 2744 * The 'spec.type' is the size of the value in bytes. 2745 */ 2746 static unsigned long long convert_num_spec(unsigned int val, struct printf_spec spec) 2747 { 2748 unsigned int shift = 32 - spec.type*8; 2749 2750 val <<= shift; 2751 if (!(spec.flags & SIGN)) 2752 return val >> shift; 2753 return (int)val >> shift; 2754 } 2755 2756 /** 2757 * vsnprintf - Format a string and place it in a buffer 2758 * @buf: The buffer to place the result into 2759 * @size: The size of the buffer, including the trailing null space 2760 * @fmt: The format string to use 2761 * @args: Arguments for the format string 2762 * 2763 * This function generally follows C99 vsnprintf, but has some 2764 * extensions and a few limitations: 2765 * 2766 * - ``%n`` is unsupported 2767 * - ``%p*`` is handled by pointer() 2768 * 2769 * See pointer() or Documentation/core-api/printk-formats.rst for more 2770 * extensive description. 2771 * 2772 * **Please update the documentation in both places when making changes** 2773 * 2774 * The return value is the number of characters which would 2775 * be generated for the given input, excluding the trailing 2776 * '\0', as per ISO C99. If you want to have the exact 2777 * number of characters written into @buf as return value 2778 * (not including the trailing '\0'), use vscnprintf(). If the 2779 * return is greater than or equal to @size, the resulting 2780 * string is truncated. 2781 * 2782 * If you're not already dealing with a va_list consider using snprintf(). 2783 */ 2784 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2785 { 2786 unsigned long long num; 2787 char *str, *end; 2788 struct printf_spec spec = {0}; 2789 2790 /* Reject out-of-range values early. Large positive sizes are 2791 used for unknown buffer sizes. */ 2792 if (WARN_ON_ONCE(size > INT_MAX)) 2793 return 0; 2794 2795 str = buf; 2796 end = buf + size; 2797 2798 /* Make sure end is always >= buf */ 2799 if (end < buf) { 2800 end = ((void *)-1); 2801 size = end - buf; 2802 } 2803 2804 while (*fmt) { 2805 const char *old_fmt = fmt; 2806 int read = format_decode(fmt, &spec); 2807 2808 fmt += read; 2809 2810 switch (spec.type) { 2811 case FORMAT_TYPE_NONE: { 2812 int copy = read; 2813 if (str < end) { 2814 if (copy > end - str) 2815 copy = end - str; 2816 memcpy(str, old_fmt, copy); 2817 } 2818 str += read; 2819 break; 2820 } 2821 2822 case FORMAT_TYPE_WIDTH: 2823 set_field_width(&spec, va_arg(args, int)); 2824 break; 2825 2826 case FORMAT_TYPE_PRECISION: 2827 set_precision(&spec, va_arg(args, int)); 2828 break; 2829 2830 case FORMAT_TYPE_CHAR: { 2831 char c; 2832 2833 if (!(spec.flags & LEFT)) { 2834 while (--spec.field_width > 0) { 2835 if (str < end) 2836 *str = ' '; 2837 ++str; 2838 2839 } 2840 } 2841 c = (unsigned char) va_arg(args, int); 2842 if (str < end) 2843 *str = c; 2844 ++str; 2845 while (--spec.field_width > 0) { 2846 if (str < end) 2847 *str = ' '; 2848 ++str; 2849 } 2850 break; 2851 } 2852 2853 case FORMAT_TYPE_STR: 2854 str = string(str, end, va_arg(args, char *), spec); 2855 break; 2856 2857 case FORMAT_TYPE_PTR: 2858 str = pointer(fmt, str, end, va_arg(args, void *), 2859 spec); 2860 while (isalnum(*fmt)) 2861 fmt++; 2862 break; 2863 2864 case FORMAT_TYPE_PERCENT_CHAR: 2865 if (str < end) 2866 *str = '%'; 2867 ++str; 2868 break; 2869 2870 case FORMAT_TYPE_INVALID: 2871 /* 2872 * Presumably the arguments passed gcc's type 2873 * checking, but there is no safe or sane way 2874 * for us to continue parsing the format and 2875 * fetching from the va_list; the remaining 2876 * specifiers and arguments would be out of 2877 * sync. 2878 */ 2879 goto out; 2880 2881 default: 2882 if (spec.type == FORMAT_TYPE_8BYTE) 2883 num = va_arg(args, long long); 2884 else 2885 num = convert_num_spec(va_arg(args, int), spec); 2886 2887 str = number(str, end, num, spec); 2888 } 2889 } 2890 2891 out: 2892 if (size > 0) { 2893 if (str < end) 2894 *str = '\0'; 2895 else 2896 end[-1] = '\0'; 2897 } 2898 2899 /* the trailing null byte doesn't count towards the total */ 2900 return str-buf; 2901 2902 } 2903 EXPORT_SYMBOL(vsnprintf); 2904 2905 /** 2906 * vscnprintf - Format a string and place it in a buffer 2907 * @buf: The buffer to place the result into 2908 * @size: The size of the buffer, including the trailing null space 2909 * @fmt: The format string to use 2910 * @args: Arguments for the format string 2911 * 2912 * The return value is the number of characters which have been written into 2913 * the @buf not including the trailing '\0'. If @size is == 0 the function 2914 * returns 0. 2915 * 2916 * If you're not already dealing with a va_list consider using scnprintf(). 2917 * 2918 * See the vsnprintf() documentation for format string extensions over C99. 2919 */ 2920 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2921 { 2922 int i; 2923 2924 if (unlikely(!size)) 2925 return 0; 2926 2927 i = vsnprintf(buf, size, fmt, args); 2928 2929 if (likely(i < size)) 2930 return i; 2931 2932 return size - 1; 2933 } 2934 EXPORT_SYMBOL(vscnprintf); 2935 2936 /** 2937 * snprintf - Format a string and place it in a buffer 2938 * @buf: The buffer to place the result into 2939 * @size: The size of the buffer, including the trailing null space 2940 * @fmt: The format string to use 2941 * @...: Arguments for the format string 2942 * 2943 * The return value is the number of characters which would be 2944 * generated for the given input, excluding the trailing null, 2945 * as per ISO C99. If the return is greater than or equal to 2946 * @size, the resulting string is truncated. 2947 * 2948 * See the vsnprintf() documentation for format string extensions over C99. 2949 */ 2950 int snprintf(char *buf, size_t size, const char *fmt, ...) 2951 { 2952 va_list args; 2953 int i; 2954 2955 va_start(args, fmt); 2956 i = vsnprintf(buf, size, fmt, args); 2957 va_end(args); 2958 2959 return i; 2960 } 2961 EXPORT_SYMBOL(snprintf); 2962 2963 /** 2964 * scnprintf - Format a string and place it in a buffer 2965 * @buf: The buffer to place the result into 2966 * @size: The size of the buffer, including the trailing null space 2967 * @fmt: The format string to use 2968 * @...: Arguments for the format string 2969 * 2970 * The return value is the number of characters written into @buf not including 2971 * the trailing '\0'. If @size is == 0 the function returns 0. 2972 */ 2973 2974 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2975 { 2976 va_list args; 2977 int i; 2978 2979 va_start(args, fmt); 2980 i = vscnprintf(buf, size, fmt, args); 2981 va_end(args); 2982 2983 return i; 2984 } 2985 EXPORT_SYMBOL(scnprintf); 2986 2987 /** 2988 * vsprintf - Format a string and place it in a buffer 2989 * @buf: The buffer to place the result into 2990 * @fmt: The format string to use 2991 * @args: Arguments for the format string 2992 * 2993 * The function returns the number of characters written 2994 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2995 * buffer overflows. 2996 * 2997 * If you're not already dealing with a va_list consider using sprintf(). 2998 * 2999 * See the vsnprintf() documentation for format string extensions over C99. 3000 */ 3001 int vsprintf(char *buf, const char *fmt, va_list args) 3002 { 3003 return vsnprintf(buf, INT_MAX, fmt, args); 3004 } 3005 EXPORT_SYMBOL(vsprintf); 3006 3007 /** 3008 * sprintf - Format a string and place it in a buffer 3009 * @buf: The buffer to place the result into 3010 * @fmt: The format string to use 3011 * @...: Arguments for the format string 3012 * 3013 * The function returns the number of characters written 3014 * into @buf. Use snprintf() or scnprintf() in order to avoid 3015 * buffer overflows. 3016 * 3017 * See the vsnprintf() documentation for format string extensions over C99. 3018 */ 3019 int sprintf(char *buf, const char *fmt, ...) 3020 { 3021 va_list args; 3022 int i; 3023 3024 va_start(args, fmt); 3025 i = vsnprintf(buf, INT_MAX, fmt, args); 3026 va_end(args); 3027 3028 return i; 3029 } 3030 EXPORT_SYMBOL(sprintf); 3031 3032 #ifdef CONFIG_BINARY_PRINTF 3033 /* 3034 * bprintf service: 3035 * vbin_printf() - VA arguments to binary data 3036 * bstr_printf() - Binary data to text string 3037 */ 3038 3039 /** 3040 * vbin_printf - Parse a format string and place args' binary value in a buffer 3041 * @bin_buf: The buffer to place args' binary value 3042 * @size: The size of the buffer(by words(32bits), not characters) 3043 * @fmt: The format string to use 3044 * @args: Arguments for the format string 3045 * 3046 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3047 * is skipped. 3048 * 3049 * The return value is the number of words(32bits) which would be generated for 3050 * the given input. 3051 * 3052 * NOTE: 3053 * If the return value is greater than @size, the resulting bin_buf is NOT 3054 * valid for bstr_printf(). 3055 */ 3056 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 3057 { 3058 struct printf_spec spec = {0}; 3059 char *str, *end; 3060 int width; 3061 3062 str = (char *)bin_buf; 3063 end = (char *)(bin_buf + size); 3064 3065 #define save_arg(type) \ 3066 ({ \ 3067 unsigned long long value; \ 3068 if (sizeof(type) == 8) { \ 3069 unsigned long long val8; \ 3070 str = PTR_ALIGN(str, sizeof(u32)); \ 3071 val8 = va_arg(args, unsigned long long); \ 3072 if (str + sizeof(type) <= end) { \ 3073 *(u32 *)str = *(u32 *)&val8; \ 3074 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3075 } \ 3076 value = val8; \ 3077 } else { \ 3078 unsigned int val4; \ 3079 str = PTR_ALIGN(str, sizeof(type)); \ 3080 val4 = va_arg(args, int); \ 3081 if (str + sizeof(type) <= end) \ 3082 *(typeof(type) *)str = (type)(long)val4; \ 3083 value = (unsigned long long)val4; \ 3084 } \ 3085 str += sizeof(type); \ 3086 value; \ 3087 }) 3088 3089 while (*fmt) { 3090 int read = format_decode(fmt, &spec); 3091 3092 fmt += read; 3093 3094 switch (spec.type) { 3095 case FORMAT_TYPE_NONE: 3096 case FORMAT_TYPE_PERCENT_CHAR: 3097 break; 3098 case FORMAT_TYPE_INVALID: 3099 goto out; 3100 3101 case FORMAT_TYPE_WIDTH: 3102 case FORMAT_TYPE_PRECISION: 3103 width = (int)save_arg(int); 3104 /* Pointers may require the width */ 3105 if (*fmt == 'p') 3106 set_field_width(&spec, width); 3107 break; 3108 3109 case FORMAT_TYPE_CHAR: 3110 save_arg(char); 3111 break; 3112 3113 case FORMAT_TYPE_STR: { 3114 const char *save_str = va_arg(args, char *); 3115 const char *err_msg; 3116 size_t len; 3117 3118 err_msg = check_pointer_msg(save_str); 3119 if (err_msg) 3120 save_str = err_msg; 3121 3122 len = strlen(save_str) + 1; 3123 if (str + len < end) 3124 memcpy(str, save_str, len); 3125 str += len; 3126 break; 3127 } 3128 3129 case FORMAT_TYPE_PTR: 3130 /* Dereferenced pointers must be done now */ 3131 switch (*fmt) { 3132 /* Dereference of functions is still OK */ 3133 case 'S': 3134 case 's': 3135 case 'x': 3136 case 'K': 3137 case 'e': 3138 save_arg(void *); 3139 break; 3140 default: 3141 if (!isalnum(*fmt)) { 3142 save_arg(void *); 3143 break; 3144 } 3145 str = pointer(fmt, str, end, va_arg(args, void *), 3146 spec); 3147 if (str + 1 < end) 3148 *str++ = '\0'; 3149 else 3150 end[-1] = '\0'; /* Must be nul terminated */ 3151 } 3152 /* skip all alphanumeric pointer suffixes */ 3153 while (isalnum(*fmt)) 3154 fmt++; 3155 break; 3156 3157 default: 3158 switch (spec.type) { 3159 case FORMAT_TYPE_8BYTE: 3160 save_arg(long long); 3161 break; 3162 case FORMAT_TYPE_1BYTE: 3163 save_arg(char); 3164 break; 3165 case FORMAT_TYPE_2BYTE: 3166 save_arg(short); 3167 break; 3168 default: 3169 save_arg(int); 3170 } 3171 } 3172 } 3173 3174 out: 3175 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3176 #undef save_arg 3177 } 3178 EXPORT_SYMBOL_GPL(vbin_printf); 3179 3180 /** 3181 * bstr_printf - Format a string from binary arguments and place it in a buffer 3182 * @buf: The buffer to place the result into 3183 * @size: The size of the buffer, including the trailing null space 3184 * @fmt: The format string to use 3185 * @bin_buf: Binary arguments for the format string 3186 * 3187 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3188 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3189 * a binary buffer that generated by vbin_printf. 3190 * 3191 * The format follows C99 vsnprintf, but has some extensions: 3192 * see vsnprintf comment for details. 3193 * 3194 * The return value is the number of characters which would 3195 * be generated for the given input, excluding the trailing 3196 * '\0', as per ISO C99. If you want to have the exact 3197 * number of characters written into @buf as return value 3198 * (not including the trailing '\0'), use vscnprintf(). If the 3199 * return is greater than or equal to @size, the resulting 3200 * string is truncated. 3201 */ 3202 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 3203 { 3204 struct printf_spec spec = {0}; 3205 char *str, *end; 3206 const char *args = (const char *)bin_buf; 3207 3208 if (WARN_ON_ONCE(size > INT_MAX)) 3209 return 0; 3210 3211 str = buf; 3212 end = buf + size; 3213 3214 #define get_arg(type) \ 3215 ({ \ 3216 typeof(type) value; \ 3217 if (sizeof(type) == 8) { \ 3218 args = PTR_ALIGN(args, sizeof(u32)); \ 3219 *(u32 *)&value = *(u32 *)args; \ 3220 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3221 } else { \ 3222 args = PTR_ALIGN(args, sizeof(type)); \ 3223 value = *(typeof(type) *)args; \ 3224 } \ 3225 args += sizeof(type); \ 3226 value; \ 3227 }) 3228 3229 /* Make sure end is always >= buf */ 3230 if (end < buf) { 3231 end = ((void *)-1); 3232 size = end - buf; 3233 } 3234 3235 while (*fmt) { 3236 const char *old_fmt = fmt; 3237 int read = format_decode(fmt, &spec); 3238 3239 fmt += read; 3240 3241 switch (spec.type) { 3242 case FORMAT_TYPE_NONE: { 3243 int copy = read; 3244 if (str < end) { 3245 if (copy > end - str) 3246 copy = end - str; 3247 memcpy(str, old_fmt, copy); 3248 } 3249 str += read; 3250 break; 3251 } 3252 3253 case FORMAT_TYPE_WIDTH: 3254 set_field_width(&spec, get_arg(int)); 3255 break; 3256 3257 case FORMAT_TYPE_PRECISION: 3258 set_precision(&spec, get_arg(int)); 3259 break; 3260 3261 case FORMAT_TYPE_CHAR: { 3262 char c; 3263 3264 if (!(spec.flags & LEFT)) { 3265 while (--spec.field_width > 0) { 3266 if (str < end) 3267 *str = ' '; 3268 ++str; 3269 } 3270 } 3271 c = (unsigned char) get_arg(char); 3272 if (str < end) 3273 *str = c; 3274 ++str; 3275 while (--spec.field_width > 0) { 3276 if (str < end) 3277 *str = ' '; 3278 ++str; 3279 } 3280 break; 3281 } 3282 3283 case FORMAT_TYPE_STR: { 3284 const char *str_arg = args; 3285 args += strlen(str_arg) + 1; 3286 str = string(str, end, (char *)str_arg, spec); 3287 break; 3288 } 3289 3290 case FORMAT_TYPE_PTR: { 3291 bool process = false; 3292 int copy, len; 3293 /* Non function dereferences were already done */ 3294 switch (*fmt) { 3295 case 'S': 3296 case 's': 3297 case 'x': 3298 case 'K': 3299 case 'e': 3300 process = true; 3301 break; 3302 default: 3303 if (!isalnum(*fmt)) { 3304 process = true; 3305 break; 3306 } 3307 /* Pointer dereference was already processed */ 3308 if (str < end) { 3309 len = copy = strlen(args); 3310 if (copy > end - str) 3311 copy = end - str; 3312 memcpy(str, args, copy); 3313 str += len; 3314 args += len + 1; 3315 } 3316 } 3317 if (process) 3318 str = pointer(fmt, str, end, get_arg(void *), spec); 3319 3320 while (isalnum(*fmt)) 3321 fmt++; 3322 break; 3323 } 3324 3325 case FORMAT_TYPE_PERCENT_CHAR: 3326 if (str < end) 3327 *str = '%'; 3328 ++str; 3329 break; 3330 3331 case FORMAT_TYPE_INVALID: 3332 goto out; 3333 3334 default: { 3335 unsigned long long num; 3336 3337 switch (spec.type) { 3338 case FORMAT_TYPE_8BYTE: 3339 num = get_arg(long long); 3340 break; 3341 case FORMAT_TYPE_2BYTE: 3342 num = convert_num_spec(get_arg(short), spec); 3343 break; 3344 case FORMAT_TYPE_1BYTE: 3345 num = convert_num_spec(get_arg(char), spec); 3346 break; 3347 default: 3348 num = convert_num_spec(get_arg(int), spec); 3349 } 3350 3351 str = number(str, end, num, spec); 3352 } /* default: */ 3353 } /* switch(spec.type) */ 3354 } /* while(*fmt) */ 3355 3356 out: 3357 if (size > 0) { 3358 if (str < end) 3359 *str = '\0'; 3360 else 3361 end[-1] = '\0'; 3362 } 3363 3364 #undef get_arg 3365 3366 /* the trailing null byte doesn't count towards the total */ 3367 return str - buf; 3368 } 3369 EXPORT_SYMBOL_GPL(bstr_printf); 3370 3371 #endif /* CONFIG_BINARY_PRINTF */ 3372 3373 /** 3374 * vsscanf - Unformat a buffer into a list of arguments 3375 * @buf: input buffer 3376 * @fmt: format of buffer 3377 * @args: arguments 3378 */ 3379 int vsscanf(const char *buf, const char *fmt, va_list args) 3380 { 3381 const char *str = buf; 3382 char *next; 3383 char digit; 3384 int num = 0; 3385 u8 qualifier; 3386 unsigned int base; 3387 union { 3388 long long s; 3389 unsigned long long u; 3390 } val; 3391 s16 field_width; 3392 bool is_sign; 3393 3394 while (*fmt) { 3395 /* skip any white space in format */ 3396 /* white space in format matches any amount of 3397 * white space, including none, in the input. 3398 */ 3399 if (isspace(*fmt)) { 3400 fmt = skip_spaces(++fmt); 3401 str = skip_spaces(str); 3402 } 3403 3404 /* anything that is not a conversion must match exactly */ 3405 if (*fmt != '%' && *fmt) { 3406 if (*fmt++ != *str++) 3407 break; 3408 continue; 3409 } 3410 3411 if (!*fmt) 3412 break; 3413 ++fmt; 3414 3415 /* skip this conversion. 3416 * advance both strings to next white space 3417 */ 3418 if (*fmt == '*') { 3419 if (!*str) 3420 break; 3421 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3422 /* '%*[' not yet supported, invalid format */ 3423 if (*fmt == '[') 3424 return num; 3425 fmt++; 3426 } 3427 while (!isspace(*str) && *str) 3428 str++; 3429 continue; 3430 } 3431 3432 /* get field width */ 3433 field_width = -1; 3434 if (isdigit(*fmt)) { 3435 field_width = skip_atoi(&fmt); 3436 if (field_width <= 0) 3437 break; 3438 } 3439 3440 /* get conversion qualifier */ 3441 qualifier = -1; 3442 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3443 *fmt == 'z') { 3444 qualifier = *fmt++; 3445 if (unlikely(qualifier == *fmt)) { 3446 if (qualifier == 'h') { 3447 qualifier = 'H'; 3448 fmt++; 3449 } else if (qualifier == 'l') { 3450 qualifier = 'L'; 3451 fmt++; 3452 } 3453 } 3454 } 3455 3456 if (!*fmt) 3457 break; 3458 3459 if (*fmt == 'n') { 3460 /* return number of characters read so far */ 3461 *va_arg(args, int *) = str - buf; 3462 ++fmt; 3463 continue; 3464 } 3465 3466 if (!*str) 3467 break; 3468 3469 base = 10; 3470 is_sign = false; 3471 3472 switch (*fmt++) { 3473 case 'c': 3474 { 3475 char *s = (char *)va_arg(args, char*); 3476 if (field_width == -1) 3477 field_width = 1; 3478 do { 3479 *s++ = *str++; 3480 } while (--field_width > 0 && *str); 3481 num++; 3482 } 3483 continue; 3484 case 's': 3485 { 3486 char *s = (char *)va_arg(args, char *); 3487 if (field_width == -1) 3488 field_width = SHRT_MAX; 3489 /* first, skip leading white space in buffer */ 3490 str = skip_spaces(str); 3491 3492 /* now copy until next white space */ 3493 while (*str && !isspace(*str) && field_width--) 3494 *s++ = *str++; 3495 *s = '\0'; 3496 num++; 3497 } 3498 continue; 3499 /* 3500 * Warning: This implementation of the '[' conversion specifier 3501 * deviates from its glibc counterpart in the following ways: 3502 * (1) It does NOT support ranges i.e. '-' is NOT a special 3503 * character 3504 * (2) It cannot match the closing bracket ']' itself 3505 * (3) A field width is required 3506 * (4) '%*[' (discard matching input) is currently not supported 3507 * 3508 * Example usage: 3509 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3510 * buf1, buf2, buf3); 3511 * if (ret < 3) 3512 * // etc.. 3513 */ 3514 case '[': 3515 { 3516 char *s = (char *)va_arg(args, char *); 3517 DECLARE_BITMAP(set, 256) = {0}; 3518 unsigned int len = 0; 3519 bool negate = (*fmt == '^'); 3520 3521 /* field width is required */ 3522 if (field_width == -1) 3523 return num; 3524 3525 if (negate) 3526 ++fmt; 3527 3528 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3529 __set_bit((u8)*fmt, set); 3530 3531 /* no ']' or no character set found */ 3532 if (!*fmt || !len) 3533 return num; 3534 ++fmt; 3535 3536 if (negate) { 3537 bitmap_complement(set, set, 256); 3538 /* exclude null '\0' byte */ 3539 __clear_bit(0, set); 3540 } 3541 3542 /* match must be non-empty */ 3543 if (!test_bit((u8)*str, set)) 3544 return num; 3545 3546 while (test_bit((u8)*str, set) && field_width--) 3547 *s++ = *str++; 3548 *s = '\0'; 3549 ++num; 3550 } 3551 continue; 3552 case 'o': 3553 base = 8; 3554 break; 3555 case 'x': 3556 case 'X': 3557 base = 16; 3558 break; 3559 case 'i': 3560 base = 0; 3561 fallthrough; 3562 case 'd': 3563 is_sign = true; 3564 fallthrough; 3565 case 'u': 3566 break; 3567 case '%': 3568 /* looking for '%' in str */ 3569 if (*str++ != '%') 3570 return num; 3571 continue; 3572 default: 3573 /* invalid format; stop here */ 3574 return num; 3575 } 3576 3577 /* have some sort of integer conversion. 3578 * first, skip white space in buffer. 3579 */ 3580 str = skip_spaces(str); 3581 3582 digit = *str; 3583 if (is_sign && digit == '-') { 3584 if (field_width == 1) 3585 break; 3586 3587 digit = *(str + 1); 3588 } 3589 3590 if (!digit 3591 || (base == 16 && !isxdigit(digit)) 3592 || (base == 10 && !isdigit(digit)) 3593 || (base == 8 && !isodigit(digit)) 3594 || (base == 0 && !isdigit(digit))) 3595 break; 3596 3597 if (is_sign) 3598 val.s = simple_strntoll(str, &next, base, 3599 field_width >= 0 ? field_width : INT_MAX); 3600 else 3601 val.u = simple_strntoull(str, &next, base, 3602 field_width >= 0 ? field_width : INT_MAX); 3603 3604 switch (qualifier) { 3605 case 'H': /* that's 'hh' in format */ 3606 if (is_sign) 3607 *va_arg(args, signed char *) = val.s; 3608 else 3609 *va_arg(args, unsigned char *) = val.u; 3610 break; 3611 case 'h': 3612 if (is_sign) 3613 *va_arg(args, short *) = val.s; 3614 else 3615 *va_arg(args, unsigned short *) = val.u; 3616 break; 3617 case 'l': 3618 if (is_sign) 3619 *va_arg(args, long *) = val.s; 3620 else 3621 *va_arg(args, unsigned long *) = val.u; 3622 break; 3623 case 'L': 3624 if (is_sign) 3625 *va_arg(args, long long *) = val.s; 3626 else 3627 *va_arg(args, unsigned long long *) = val.u; 3628 break; 3629 case 'z': 3630 *va_arg(args, size_t *) = val.u; 3631 break; 3632 default: 3633 if (is_sign) 3634 *va_arg(args, int *) = val.s; 3635 else 3636 *va_arg(args, unsigned int *) = val.u; 3637 break; 3638 } 3639 num++; 3640 3641 if (!next) 3642 break; 3643 str = next; 3644 } 3645 3646 return num; 3647 } 3648 EXPORT_SYMBOL(vsscanf); 3649 3650 /** 3651 * sscanf - Unformat a buffer into a list of arguments 3652 * @buf: input buffer 3653 * @fmt: formatting of buffer 3654 * @...: resulting arguments 3655 */ 3656 int sscanf(const char *buf, const char *fmt, ...) 3657 { 3658 va_list args; 3659 int i; 3660 3661 va_start(args, fmt); 3662 i = vsscanf(buf, fmt, args); 3663 va_end(args); 3664 3665 return i; 3666 } 3667 EXPORT_SYMBOL(sscanf); 3668