1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/lib/vsprintf.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 */ 7 8 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ 9 /* 10 * Wirzenius wrote this portably, Torvalds fucked it up :-) 11 */ 12 13 /* 14 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com> 15 * - changed to provide snprintf and vsnprintf functions 16 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> 17 * - scnprintf and vscnprintf 18 */ 19 20 #include <linux/stdarg.h> 21 #include <linux/build_bug.h> 22 #include <linux/clk.h> 23 #include <linux/clk-provider.h> 24 #include <linux/errname.h> 25 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */ 26 #include <linux/types.h> 27 #include <linux/string.h> 28 #include <linux/ctype.h> 29 #include <linux/kernel.h> 30 #include <linux/kallsyms.h> 31 #include <linux/math64.h> 32 #include <linux/uaccess.h> 33 #include <linux/ioport.h> 34 #include <linux/dcache.h> 35 #include <linux/cred.h> 36 #include <linux/rtc.h> 37 #include <linux/sprintf.h> 38 #include <linux/time.h> 39 #include <linux/uuid.h> 40 #include <linux/of.h> 41 #include <net/addrconf.h> 42 #include <linux/siphash.h> 43 #include <linux/compiler.h> 44 #include <linux/property.h> 45 #include <linux/notifier.h> 46 #ifdef CONFIG_BLOCK 47 #include <linux/blkdev.h> 48 #endif 49 50 #include "../mm/internal.h" /* For the trace_print_flags arrays */ 51 52 #include <asm/page.h> /* for PAGE_SIZE */ 53 #include <asm/byteorder.h> /* cpu_to_le16 */ 54 #include <linux/unaligned.h> 55 56 #include <linux/string_helpers.h> 57 #include "kstrtox.h" 58 59 /* Disable pointer hashing if requested */ 60 bool no_hash_pointers __ro_after_init; 61 EXPORT_SYMBOL_GPL(no_hash_pointers); 62 63 noinline 64 static unsigned long long simple_strntoull(const char *startp, char **endp, unsigned int base, size_t max_chars) 65 { 66 const char *cp; 67 unsigned long long result = 0ULL; 68 size_t prefix_chars; 69 unsigned int rv; 70 71 cp = _parse_integer_fixup_radix(startp, &base); 72 prefix_chars = cp - startp; 73 if (prefix_chars < max_chars) { 74 rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); 75 /* FIXME */ 76 cp += (rv & ~KSTRTOX_OVERFLOW); 77 } else { 78 /* Field too short for prefix + digit, skip over without converting */ 79 cp = startp + max_chars; 80 } 81 82 if (endp) 83 *endp = (char *)cp; 84 85 return result; 86 } 87 88 /** 89 * simple_strtoull - convert a string to an unsigned long long 90 * @cp: The start of the string 91 * @endp: A pointer to the end of the parsed string will be placed here 92 * @base: The number base to use 93 * 94 * This function has caveats. Please use kstrtoull instead. 95 */ 96 noinline 97 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 98 { 99 return simple_strntoull(cp, endp, base, INT_MAX); 100 } 101 EXPORT_SYMBOL(simple_strtoull); 102 103 /** 104 * simple_strtoul - convert a string to an unsigned long 105 * @cp: The start of the string 106 * @endp: A pointer to the end of the parsed string will be placed here 107 * @base: The number base to use 108 * 109 * This function has caveats. Please use kstrtoul instead. 110 */ 111 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 112 { 113 return simple_strtoull(cp, endp, base); 114 } 115 EXPORT_SYMBOL(simple_strtoul); 116 117 unsigned long simple_strntoul(const char *cp, char **endp, unsigned int base, 118 size_t max_chars) 119 { 120 return simple_strntoull(cp, endp, base, max_chars); 121 } 122 EXPORT_SYMBOL(simple_strntoul); 123 124 /** 125 * simple_strtol - convert a string to a signed long 126 * @cp: The start of the string 127 * @endp: A pointer to the end of the parsed string will be placed here 128 * @base: The number base to use 129 * 130 * This function has caveats. Please use kstrtol instead. 131 */ 132 long simple_strtol(const char *cp, char **endp, unsigned int base) 133 { 134 if (*cp == '-') 135 return -simple_strtoul(cp + 1, endp, base); 136 137 return simple_strtoul(cp, endp, base); 138 } 139 EXPORT_SYMBOL(simple_strtol); 140 141 noinline 142 static long long simple_strntoll(const char *cp, char **endp, unsigned int base, size_t max_chars) 143 { 144 /* 145 * simple_strntoull() safely handles receiving max_chars==0 in the 146 * case cp[0] == '-' && max_chars == 1. 147 * If max_chars == 0 we can drop through and pass it to simple_strntoull() 148 * and the content of *cp is irrelevant. 149 */ 150 if (*cp == '-' && max_chars > 0) 151 return -simple_strntoull(cp + 1, endp, base, max_chars - 1); 152 153 return simple_strntoull(cp, endp, base, max_chars); 154 } 155 156 /** 157 * simple_strtoll - convert a string to a signed long long 158 * @cp: The start of the string 159 * @endp: A pointer to the end of the parsed string will be placed here 160 * @base: The number base to use 161 * 162 * This function has caveats. Please use kstrtoll instead. 163 */ 164 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 165 { 166 return simple_strntoll(cp, endp, base, INT_MAX); 167 } 168 EXPORT_SYMBOL(simple_strtoll); 169 170 static inline int skip_atoi(const char **s) 171 { 172 int i = 0; 173 174 do { 175 i = i*10 + *((*s)++) - '0'; 176 } while (isdigit(**s)); 177 178 return i; 179 } 180 181 /* 182 * Decimal conversion is by far the most typical, and is used for 183 * /proc and /sys data. This directly impacts e.g. top performance 184 * with many processes running. We optimize it for speed by emitting 185 * two characters at a time, using a 200 byte lookup table. This 186 * roughly halves the number of multiplications compared to computing 187 * the digits one at a time. Implementation strongly inspired by the 188 * previous version, which in turn used ideas described at 189 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 190 * from the author, Douglas W. Jones). 191 * 192 * It turns out there is precisely one 26 bit fixed-point 193 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 194 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 195 * range happens to be somewhat larger (x <= 1073741898), but that's 196 * irrelevant for our purpose. 197 * 198 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 199 * need a 32x32->64 bit multiply, so we simply use the same constant. 200 * 201 * For dividing a number in the range [100, 10^4-1] by 100, there are 202 * several options. The simplest is (x * 0x147b) >> 19, which is valid 203 * for all x <= 43698. 204 */ 205 206 static const u16 decpair[100] = { 207 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 208 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 209 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 210 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 211 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 212 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 213 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 214 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 215 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 216 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 217 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 218 #undef _ 219 }; 220 221 /* 222 * This will print a single '0' even if r == 0, since we would 223 * immediately jump to out_r where two 0s would be written but only 224 * one of them accounted for in buf. This is needed by ip4_string 225 * below. All other callers pass a non-zero value of r. 226 */ 227 static noinline_for_stack 228 char *put_dec_trunc8(char *buf, unsigned r) 229 { 230 unsigned q; 231 232 /* 1 <= r < 10^8 */ 233 if (r < 100) 234 goto out_r; 235 236 /* 100 <= r < 10^8 */ 237 q = (r * (u64)0x28f5c29) >> 32; 238 *((u16 *)buf) = decpair[r - 100*q]; 239 buf += 2; 240 241 /* 1 <= q < 10^6 */ 242 if (q < 100) 243 goto out_q; 244 245 /* 100 <= q < 10^6 */ 246 r = (q * (u64)0x28f5c29) >> 32; 247 *((u16 *)buf) = decpair[q - 100*r]; 248 buf += 2; 249 250 /* 1 <= r < 10^4 */ 251 if (r < 100) 252 goto out_r; 253 254 /* 100 <= r < 10^4 */ 255 q = (r * 0x147b) >> 19; 256 *((u16 *)buf) = decpair[r - 100*q]; 257 buf += 2; 258 out_q: 259 /* 1 <= q < 100 */ 260 r = q; 261 out_r: 262 /* 1 <= r < 100 */ 263 *((u16 *)buf) = decpair[r]; 264 buf += r < 10 ? 1 : 2; 265 return buf; 266 } 267 268 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 269 static noinline_for_stack 270 char *put_dec_full8(char *buf, unsigned r) 271 { 272 unsigned q; 273 274 /* 0 <= r < 10^8 */ 275 q = (r * (u64)0x28f5c29) >> 32; 276 *((u16 *)buf) = decpair[r - 100*q]; 277 buf += 2; 278 279 /* 0 <= q < 10^6 */ 280 r = (q * (u64)0x28f5c29) >> 32; 281 *((u16 *)buf) = decpair[q - 100*r]; 282 buf += 2; 283 284 /* 0 <= r < 10^4 */ 285 q = (r * 0x147b) >> 19; 286 *((u16 *)buf) = decpair[r - 100*q]; 287 buf += 2; 288 289 /* 0 <= q < 100 */ 290 *((u16 *)buf) = decpair[q]; 291 buf += 2; 292 return buf; 293 } 294 295 static noinline_for_stack 296 char *put_dec(char *buf, unsigned long long n) 297 { 298 if (n >= 100*1000*1000) 299 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 300 /* 1 <= n <= 1.6e11 */ 301 if (n >= 100*1000*1000) 302 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 303 /* 1 <= n < 1e8 */ 304 return put_dec_trunc8(buf, n); 305 } 306 307 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 308 309 static void 310 put_dec_full4(char *buf, unsigned r) 311 { 312 unsigned q; 313 314 /* 0 <= r < 10^4 */ 315 q = (r * 0x147b) >> 19; 316 *((u16 *)buf) = decpair[r - 100*q]; 317 buf += 2; 318 /* 0 <= q < 100 */ 319 *((u16 *)buf) = decpair[q]; 320 } 321 322 /* 323 * Call put_dec_full4 on x % 10000, return x / 10000. 324 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 325 * holds for all x < 1,128,869,999. The largest value this 326 * helper will ever be asked to convert is 1,125,520,955. 327 * (second call in the put_dec code, assuming n is all-ones). 328 */ 329 static noinline_for_stack 330 unsigned put_dec_helper4(char *buf, unsigned x) 331 { 332 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 333 334 put_dec_full4(buf, x - q * 10000); 335 return q; 336 } 337 338 /* Based on code by Douglas W. Jones found at 339 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 340 * (with permission from the author). 341 * Performs no 64-bit division and hence should be fast on 32-bit machines. 342 */ 343 static 344 char *put_dec(char *buf, unsigned long long n) 345 { 346 uint32_t d3, d2, d1, q, h; 347 348 if (n < 100*1000*1000) 349 return put_dec_trunc8(buf, n); 350 351 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 352 h = (n >> 32); 353 d2 = (h ) & 0xffff; 354 d3 = (h >> 16); /* implicit "& 0xffff" */ 355 356 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 357 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 358 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 359 q = put_dec_helper4(buf, q); 360 361 q += 7671 * d3 + 9496 * d2 + 6 * d1; 362 q = put_dec_helper4(buf+4, q); 363 364 q += 4749 * d3 + 42 * d2; 365 q = put_dec_helper4(buf+8, q); 366 367 q += 281 * d3; 368 buf += 12; 369 if (q) 370 buf = put_dec_trunc8(buf, q); 371 else while (buf[-1] == '0') 372 --buf; 373 374 return buf; 375 } 376 377 #endif 378 379 /* 380 * Convert passed number to decimal string. 381 * Returns the length of string. On buffer overflow, returns 0. 382 * 383 * If speed is not important, use snprintf(). It's easy to read the code. 384 */ 385 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 386 { 387 /* put_dec requires 2-byte alignment of the buffer. */ 388 char tmp[sizeof(num) * 3] __aligned(2); 389 int idx, len; 390 391 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 392 if (num <= 9) { 393 tmp[0] = '0' + num; 394 len = 1; 395 } else { 396 len = put_dec(tmp, num) - tmp; 397 } 398 399 if (len > size || width > size) 400 return 0; 401 402 if (width > len) { 403 width = width - len; 404 for (idx = 0; idx < width; idx++) 405 buf[idx] = ' '; 406 } else { 407 width = 0; 408 } 409 410 for (idx = 0; idx < len; ++idx) 411 buf[idx + width] = tmp[len - idx - 1]; 412 413 return len + width; 414 } 415 416 #define SIGN 1 /* unsigned/signed */ 417 #define LEFT 2 /* left justified */ 418 #define PLUS 4 /* show plus */ 419 #define SPACE 8 /* space if plus */ 420 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 421 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 422 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 423 424 static_assert(ZEROPAD == ('0' - ' ')); 425 static_assert(SMALL == ('a' ^ 'A')); 426 427 enum format_state { 428 FORMAT_STATE_NONE, /* Just a string part */ 429 FORMAT_STATE_NUM, 430 FORMAT_STATE_WIDTH, 431 FORMAT_STATE_PRECISION, 432 FORMAT_STATE_CHAR, 433 FORMAT_STATE_STR, 434 FORMAT_STATE_PTR, 435 FORMAT_STATE_PERCENT_CHAR, 436 FORMAT_STATE_INVALID, 437 }; 438 439 struct printf_spec { 440 unsigned char flags; /* flags to number() */ 441 unsigned char base; /* number base, 8, 10 or 16 only */ 442 short precision; /* # of digits/chars */ 443 int field_width; /* width of output field */ 444 } __packed; 445 static_assert(sizeof(struct printf_spec) == 8); 446 447 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 448 #define PRECISION_MAX ((1 << 15) - 1) 449 450 static noinline_for_stack 451 char *number(char *buf, char *end, unsigned long long num, 452 struct printf_spec spec) 453 { 454 /* put_dec requires 2-byte alignment of the buffer. */ 455 char tmp[3 * sizeof(num)] __aligned(2); 456 char sign; 457 char locase; 458 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 459 int i; 460 bool is_zero = num == 0LL; 461 int field_width = spec.field_width; 462 int precision = spec.precision; 463 464 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 465 * produces same digits or (maybe lowercased) letters */ 466 locase = (spec.flags & SMALL); 467 if (spec.flags & LEFT) 468 spec.flags &= ~ZEROPAD; 469 sign = 0; 470 if (spec.flags & SIGN) { 471 if ((signed long long)num < 0) { 472 sign = '-'; 473 num = -(signed long long)num; 474 field_width--; 475 } else if (spec.flags & PLUS) { 476 sign = '+'; 477 field_width--; 478 } else if (spec.flags & SPACE) { 479 sign = ' '; 480 field_width--; 481 } 482 } 483 if (need_pfx) { 484 if (spec.base == 16) 485 field_width -= 2; 486 else if (!is_zero) 487 field_width--; 488 } 489 490 /* generate full string in tmp[], in reverse order */ 491 i = 0; 492 if (num < spec.base) 493 tmp[i++] = hex_asc_upper[num] | locase; 494 else if (spec.base != 10) { /* 8 or 16 */ 495 int mask = spec.base - 1; 496 int shift = 3; 497 498 if (spec.base == 16) 499 shift = 4; 500 do { 501 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 502 num >>= shift; 503 } while (num); 504 } else { /* base 10 */ 505 i = put_dec(tmp, num) - tmp; 506 } 507 508 /* printing 100 using %2d gives "100", not "00" */ 509 if (i > precision) 510 precision = i; 511 /* leading space padding */ 512 field_width -= precision; 513 if (!(spec.flags & (ZEROPAD | LEFT))) { 514 while (--field_width >= 0) { 515 if (buf < end) 516 *buf = ' '; 517 ++buf; 518 } 519 } 520 /* sign */ 521 if (sign) { 522 if (buf < end) 523 *buf = sign; 524 ++buf; 525 } 526 /* "0x" / "0" prefix */ 527 if (need_pfx) { 528 if (spec.base == 16 || !is_zero) { 529 if (buf < end) 530 *buf = '0'; 531 ++buf; 532 } 533 if (spec.base == 16) { 534 if (buf < end) 535 *buf = ('X' | locase); 536 ++buf; 537 } 538 } 539 /* zero or space padding */ 540 if (!(spec.flags & LEFT)) { 541 char c = ' ' + (spec.flags & ZEROPAD); 542 543 while (--field_width >= 0) { 544 if (buf < end) 545 *buf = c; 546 ++buf; 547 } 548 } 549 /* hmm even more zero padding? */ 550 while (i <= --precision) { 551 if (buf < end) 552 *buf = '0'; 553 ++buf; 554 } 555 /* actual digits of result */ 556 while (--i >= 0) { 557 if (buf < end) 558 *buf = tmp[i]; 559 ++buf; 560 } 561 /* trailing space padding */ 562 while (--field_width >= 0) { 563 if (buf < end) 564 *buf = ' '; 565 ++buf; 566 } 567 568 return buf; 569 } 570 571 static noinline_for_stack 572 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 573 { 574 struct printf_spec spec; 575 576 spec.field_width = 2 + 2 * size; /* 0x + hex */ 577 spec.flags = SPECIAL | SMALL | ZEROPAD; 578 spec.base = 16; 579 spec.precision = -1; 580 581 return number(buf, end, num, spec); 582 } 583 584 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 585 { 586 size_t size; 587 if (buf >= end) /* nowhere to put anything */ 588 return; 589 size = end - buf; 590 if (size <= spaces) { 591 memset(buf, ' ', size); 592 return; 593 } 594 if (len) { 595 if (len > size - spaces) 596 len = size - spaces; 597 memmove(buf + spaces, buf, len); 598 } 599 memset(buf, ' ', spaces); 600 } 601 602 /* 603 * Handle field width padding for a string. 604 * @buf: current buffer position 605 * @n: length of string 606 * @end: end of output buffer 607 * @spec: for field width and flags 608 * Returns: new buffer position after padding. 609 */ 610 static noinline_for_stack 611 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 612 { 613 unsigned spaces; 614 615 if (likely(n >= spec.field_width)) 616 return buf; 617 /* we want to pad the sucker */ 618 spaces = spec.field_width - n; 619 if (!(spec.flags & LEFT)) { 620 move_right(buf - n, end, n, spaces); 621 return buf + spaces; 622 } 623 while (spaces--) { 624 if (buf < end) 625 *buf = ' '; 626 ++buf; 627 } 628 return buf; 629 } 630 631 /* Handle string from a well known address. */ 632 static char *string_nocheck(char *buf, char *end, const char *s, 633 struct printf_spec spec) 634 { 635 int len = 0; 636 int lim = spec.precision; 637 638 while (lim--) { 639 char c = *s++; 640 if (!c) 641 break; 642 if (buf < end) 643 *buf = c; 644 ++buf; 645 ++len; 646 } 647 return widen_string(buf, len, end, spec); 648 } 649 650 static char *err_ptr(char *buf, char *end, void *ptr, 651 struct printf_spec spec) 652 { 653 int err = PTR_ERR(ptr); 654 const char *sym = errname(err); 655 656 if (sym) 657 return string_nocheck(buf, end, sym, spec); 658 659 /* 660 * Somebody passed ERR_PTR(-1234) or some other non-existing 661 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to 662 * printing it as its decimal representation. 663 */ 664 spec.flags |= SIGN; 665 spec.base = 10; 666 return number(buf, end, err, spec); 667 } 668 669 /* Be careful: error messages must fit into the given buffer. */ 670 static char *error_string(char *buf, char *end, const char *s, 671 struct printf_spec spec) 672 { 673 /* 674 * Hard limit to avoid a completely insane messages. It actually 675 * works pretty well because most error messages are in 676 * the many pointer format modifiers. 677 */ 678 if (spec.precision == -1) 679 spec.precision = 2 * sizeof(void *); 680 681 return string_nocheck(buf, end, s, spec); 682 } 683 684 /* 685 * Do not call any complex external code here. Nested printk()/vsprintf() 686 * might cause infinite loops. Failures might break printk() and would 687 * be hard to debug. 688 */ 689 static const char *check_pointer_msg(const void *ptr) 690 { 691 if (!ptr) 692 return "(null)"; 693 694 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 695 return "(efault)"; 696 697 return NULL; 698 } 699 700 static int check_pointer(char **buf, char *end, const void *ptr, 701 struct printf_spec spec) 702 { 703 const char *err_msg; 704 705 err_msg = check_pointer_msg(ptr); 706 if (err_msg) { 707 *buf = error_string(*buf, end, err_msg, spec); 708 return -EFAULT; 709 } 710 711 return 0; 712 } 713 714 static noinline_for_stack 715 char *string(char *buf, char *end, const char *s, 716 struct printf_spec spec) 717 { 718 if (check_pointer(&buf, end, s, spec)) 719 return buf; 720 721 return string_nocheck(buf, end, s, spec); 722 } 723 724 static char *pointer_string(char *buf, char *end, 725 const void *ptr, 726 struct printf_spec spec) 727 { 728 spec.base = 16; 729 spec.flags |= SMALL; 730 if (spec.field_width == -1) { 731 spec.field_width = 2 * sizeof(ptr); 732 spec.flags |= ZEROPAD; 733 } 734 735 return number(buf, end, (unsigned long int)ptr, spec); 736 } 737 738 /* Make pointers available for printing early in the boot sequence. */ 739 static int debug_boot_weak_hash __ro_after_init; 740 741 static int __init debug_boot_weak_hash_enable(char *str) 742 { 743 debug_boot_weak_hash = 1; 744 pr_info("debug_boot_weak_hash enabled\n"); 745 return 0; 746 } 747 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 748 749 static bool filled_random_ptr_key __read_mostly; 750 static siphash_key_t ptr_key __read_mostly; 751 752 static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) 753 { 754 get_random_bytes(&ptr_key, sizeof(ptr_key)); 755 756 /* Pairs with smp_rmb() before reading ptr_key. */ 757 smp_wmb(); 758 WRITE_ONCE(filled_random_ptr_key, true); 759 return NOTIFY_DONE; 760 } 761 762 static int __init vsprintf_init_hashval(void) 763 { 764 static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; 765 execute_with_initialized_rng(&fill_ptr_key_nb); 766 return 0; 767 } 768 subsys_initcall(vsprintf_init_hashval) 769 770 /* Maps a pointer to a 32 bit unique identifier. */ 771 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 772 { 773 unsigned long hashval; 774 775 if (!READ_ONCE(filled_random_ptr_key)) 776 return -EBUSY; 777 778 /* Pairs with smp_wmb() after writing ptr_key. */ 779 smp_rmb(); 780 781 #ifdef CONFIG_64BIT 782 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 783 /* 784 * Mask off the first 32 bits, this makes explicit that we have 785 * modified the address (and 32 bits is plenty for a unique ID). 786 */ 787 hashval = hashval & 0xffffffff; 788 #else 789 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 790 #endif 791 *hashval_out = hashval; 792 return 0; 793 } 794 795 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) 796 { 797 return __ptr_to_hashval(ptr, hashval_out); 798 } 799 800 static char *ptr_to_id(char *buf, char *end, const void *ptr, 801 struct printf_spec spec) 802 { 803 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 804 unsigned long hashval; 805 int ret; 806 807 /* 808 * Print the real pointer value for NULL and error pointers, 809 * as they are not actual addresses. 810 */ 811 if (IS_ERR_OR_NULL(ptr)) 812 return pointer_string(buf, end, ptr, spec); 813 814 /* When debugging early boot use non-cryptographically secure hash. */ 815 if (unlikely(debug_boot_weak_hash)) { 816 hashval = hash_long((unsigned long)ptr, 32); 817 return pointer_string(buf, end, (const void *)hashval, spec); 818 } 819 820 ret = __ptr_to_hashval(ptr, &hashval); 821 if (ret) { 822 spec.field_width = 2 * sizeof(ptr); 823 /* string length must be less than default_width */ 824 return error_string(buf, end, str, spec); 825 } 826 827 return pointer_string(buf, end, (const void *)hashval, spec); 828 } 829 830 static char *default_pointer(char *buf, char *end, const void *ptr, 831 struct printf_spec spec) 832 { 833 /* 834 * default is to _not_ leak addresses, so hash before printing, 835 * unless no_hash_pointers is specified on the command line. 836 */ 837 if (unlikely(no_hash_pointers)) 838 return pointer_string(buf, end, ptr, spec); 839 840 return ptr_to_id(buf, end, ptr, spec); 841 } 842 843 int kptr_restrict __read_mostly; 844 845 static noinline_for_stack 846 char *restricted_pointer(char *buf, char *end, const void *ptr, 847 struct printf_spec spec) 848 { 849 switch (kptr_restrict) { 850 case 0: 851 /* Handle as %p, hash and do _not_ leak addresses. */ 852 return default_pointer(buf, end, ptr, spec); 853 case 1: { 854 const struct cred *cred; 855 856 /* 857 * kptr_restrict==1 cannot be used in IRQ context 858 * because its test for CAP_SYSLOG would be meaningless. 859 */ 860 if (in_hardirq() || in_serving_softirq() || in_nmi()) { 861 if (spec.field_width == -1) 862 spec.field_width = 2 * sizeof(ptr); 863 return error_string(buf, end, "pK-error", spec); 864 } 865 866 /* 867 * Only print the real pointer value if the current 868 * process has CAP_SYSLOG and is running with the 869 * same credentials it started with. This is because 870 * access to files is checked at open() time, but %pK 871 * checks permission at read() time. We don't want to 872 * leak pointer values if a binary opens a file using 873 * %pK and then elevates privileges before reading it. 874 */ 875 cred = current_cred(); 876 if (!has_capability_noaudit(current, CAP_SYSLOG) || 877 !uid_eq(cred->euid, cred->uid) || 878 !gid_eq(cred->egid, cred->gid)) 879 ptr = NULL; 880 break; 881 } 882 case 2: 883 default: 884 /* Always print 0's for %pK */ 885 ptr = NULL; 886 break; 887 } 888 889 return pointer_string(buf, end, ptr, spec); 890 } 891 892 static noinline_for_stack 893 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 894 const char *fmt) 895 { 896 const char *array[4], *s; 897 const struct dentry *p; 898 int depth; 899 int i, n; 900 901 switch (fmt[1]) { 902 case '2': case '3': case '4': 903 depth = fmt[1] - '0'; 904 break; 905 default: 906 depth = 1; 907 } 908 909 rcu_read_lock(); 910 for (i = 0; i < depth; i++, d = p) { 911 if (check_pointer(&buf, end, d, spec)) { 912 rcu_read_unlock(); 913 return buf; 914 } 915 916 p = READ_ONCE(d->d_parent); 917 array[i] = READ_ONCE(d->d_name.name); 918 if (p == d) { 919 if (i) 920 array[i] = ""; 921 i++; 922 break; 923 } 924 } 925 s = array[--i]; 926 for (n = 0; n != spec.precision; n++, buf++) { 927 char c = *s++; 928 if (!c) { 929 if (!i) 930 break; 931 c = '/'; 932 s = array[--i]; 933 } 934 if (buf < end) 935 *buf = c; 936 } 937 rcu_read_unlock(); 938 return widen_string(buf, n, end, spec); 939 } 940 941 static noinline_for_stack 942 char *file_dentry_name(char *buf, char *end, const struct file *f, 943 struct printf_spec spec, const char *fmt) 944 { 945 if (check_pointer(&buf, end, f, spec)) 946 return buf; 947 948 return dentry_name(buf, end, f->f_path.dentry, spec, fmt); 949 } 950 #ifdef CONFIG_BLOCK 951 static noinline_for_stack 952 char *bdev_name(char *buf, char *end, struct block_device *bdev, 953 struct printf_spec spec, const char *fmt) 954 { 955 struct gendisk *hd; 956 957 if (check_pointer(&buf, end, bdev, spec)) 958 return buf; 959 960 hd = bdev->bd_disk; 961 buf = string(buf, end, hd->disk_name, spec); 962 if (bdev_is_partition(bdev)) { 963 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 964 if (buf < end) 965 *buf = 'p'; 966 buf++; 967 } 968 buf = number(buf, end, bdev_partno(bdev), spec); 969 } 970 return buf; 971 } 972 #endif 973 974 static noinline_for_stack 975 char *symbol_string(char *buf, char *end, void *ptr, 976 struct printf_spec spec, const char *fmt) 977 { 978 unsigned long value; 979 #ifdef CONFIG_KALLSYMS 980 char sym[KSYM_SYMBOL_LEN]; 981 #endif 982 983 if (fmt[1] == 'R') 984 ptr = __builtin_extract_return_addr(ptr); 985 value = (unsigned long)ptr; 986 987 #ifdef CONFIG_KALLSYMS 988 if (*fmt == 'B' && fmt[1] == 'b') 989 sprint_backtrace_build_id(sym, value); 990 else if (*fmt == 'B') 991 sprint_backtrace(sym, value); 992 else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) 993 sprint_symbol_build_id(sym, value); 994 else if (*fmt != 's') 995 sprint_symbol(sym, value); 996 else 997 sprint_symbol_no_offset(sym, value); 998 999 return string_nocheck(buf, end, sym, spec); 1000 #else 1001 return special_hex_number(buf, end, value, sizeof(void *)); 1002 #endif 1003 } 1004 1005 static const struct printf_spec default_str_spec = { 1006 .field_width = -1, 1007 .precision = -1, 1008 }; 1009 1010 static const struct printf_spec default_flag_spec = { 1011 .base = 16, 1012 .precision = -1, 1013 .flags = SPECIAL | SMALL, 1014 }; 1015 1016 static const struct printf_spec default_dec_spec = { 1017 .base = 10, 1018 .precision = -1, 1019 }; 1020 1021 static const struct printf_spec default_dec02_spec = { 1022 .base = 10, 1023 .field_width = 2, 1024 .precision = -1, 1025 .flags = ZEROPAD, 1026 }; 1027 1028 static const struct printf_spec default_dec04_spec = { 1029 .base = 10, 1030 .field_width = 4, 1031 .precision = -1, 1032 .flags = ZEROPAD, 1033 }; 1034 1035 static noinline_for_stack 1036 char *hex_range(char *buf, char *end, u64 start_val, u64 end_val, 1037 struct printf_spec spec) 1038 { 1039 buf = number(buf, end, start_val, spec); 1040 if (start_val == end_val) 1041 return buf; 1042 1043 if (buf < end) 1044 *buf = '-'; 1045 ++buf; 1046 return number(buf, end, end_val, spec); 1047 } 1048 1049 static noinline_for_stack 1050 char *resource_string(char *buf, char *end, struct resource *res, 1051 struct printf_spec spec, const char *fmt) 1052 { 1053 #ifndef IO_RSRC_PRINTK_SIZE 1054 #define IO_RSRC_PRINTK_SIZE 6 1055 #endif 1056 1057 #ifndef MEM_RSRC_PRINTK_SIZE 1058 #define MEM_RSRC_PRINTK_SIZE 10 1059 #endif 1060 static const struct printf_spec io_spec = { 1061 .base = 16, 1062 .field_width = IO_RSRC_PRINTK_SIZE, 1063 .precision = -1, 1064 .flags = SPECIAL | SMALL | ZEROPAD, 1065 }; 1066 static const struct printf_spec mem_spec = { 1067 .base = 16, 1068 .field_width = MEM_RSRC_PRINTK_SIZE, 1069 .precision = -1, 1070 .flags = SPECIAL | SMALL | ZEROPAD, 1071 }; 1072 static const struct printf_spec bus_spec = { 1073 .base = 16, 1074 .field_width = 2, 1075 .precision = -1, 1076 .flags = SMALL | ZEROPAD, 1077 }; 1078 static const struct printf_spec str_spec = { 1079 .field_width = -1, 1080 .precision = 10, 1081 .flags = LEFT, 1082 }; 1083 1084 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 1085 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 1086 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 1087 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 1088 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 1089 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 1090 char sym[MAX(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 1091 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 1092 1093 char *p = sym, *pend = sym + sizeof(sym); 1094 int decode = (fmt[0] == 'R') ? 1 : 0; 1095 const struct printf_spec *specp; 1096 1097 if (check_pointer(&buf, end, res, spec)) 1098 return buf; 1099 1100 *p++ = '['; 1101 if (res->flags & IORESOURCE_IO) { 1102 p = string_nocheck(p, pend, "io ", str_spec); 1103 specp = &io_spec; 1104 } else if (res->flags & IORESOURCE_MEM) { 1105 p = string_nocheck(p, pend, "mem ", str_spec); 1106 specp = &mem_spec; 1107 } else if (res->flags & IORESOURCE_IRQ) { 1108 p = string_nocheck(p, pend, "irq ", str_spec); 1109 specp = &default_dec_spec; 1110 } else if (res->flags & IORESOURCE_DMA) { 1111 p = string_nocheck(p, pend, "dma ", str_spec); 1112 specp = &default_dec_spec; 1113 } else if (res->flags & IORESOURCE_BUS) { 1114 p = string_nocheck(p, pend, "bus ", str_spec); 1115 specp = &bus_spec; 1116 } else { 1117 p = string_nocheck(p, pend, "??? ", str_spec); 1118 specp = &mem_spec; 1119 decode = 0; 1120 } 1121 if (decode && res->flags & IORESOURCE_UNSET) { 1122 p = string_nocheck(p, pend, "size ", str_spec); 1123 p = number(p, pend, resource_size(res), *specp); 1124 } else { 1125 p = hex_range(p, pend, res->start, res->end, *specp); 1126 } 1127 if (decode) { 1128 if (res->flags & IORESOURCE_MEM_64) 1129 p = string_nocheck(p, pend, " 64bit", str_spec); 1130 if (res->flags & IORESOURCE_PREFETCH) 1131 p = string_nocheck(p, pend, " pref", str_spec); 1132 if (res->flags & IORESOURCE_WINDOW) 1133 p = string_nocheck(p, pend, " window", str_spec); 1134 if (res->flags & IORESOURCE_DISABLED) 1135 p = string_nocheck(p, pend, " disabled", str_spec); 1136 } else { 1137 p = string_nocheck(p, pend, " flags ", str_spec); 1138 p = number(p, pend, res->flags, default_flag_spec); 1139 } 1140 *p++ = ']'; 1141 *p = '\0'; 1142 1143 return string_nocheck(buf, end, sym, spec); 1144 } 1145 1146 static noinline_for_stack 1147 char *range_string(char *buf, char *end, const struct range *range, 1148 struct printf_spec spec, const char *fmt) 1149 { 1150 char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")]; 1151 char *p = sym, *pend = sym + sizeof(sym); 1152 1153 struct printf_spec range_spec = { 1154 .field_width = 2 + 2 * sizeof(range->start), /* 0x + 2 * 8 */ 1155 .flags = SPECIAL | SMALL | ZEROPAD, 1156 .base = 16, 1157 .precision = -1, 1158 }; 1159 1160 if (check_pointer(&buf, end, range, spec)) 1161 return buf; 1162 1163 p = string_nocheck(p, pend, "[range ", default_str_spec); 1164 p = hex_range(p, pend, range->start, range->end, range_spec); 1165 *p++ = ']'; 1166 *p = '\0'; 1167 1168 return string_nocheck(buf, end, sym, spec); 1169 } 1170 1171 static noinline_for_stack 1172 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1173 const char *fmt) 1174 { 1175 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1176 negative value, fallback to the default */ 1177 char separator; 1178 1179 if (spec.field_width == 0) 1180 /* nothing to print */ 1181 return buf; 1182 1183 if (check_pointer(&buf, end, addr, spec)) 1184 return buf; 1185 1186 switch (fmt[1]) { 1187 case 'C': 1188 separator = ':'; 1189 break; 1190 case 'D': 1191 separator = '-'; 1192 break; 1193 case 'N': 1194 separator = 0; 1195 break; 1196 default: 1197 separator = ' '; 1198 break; 1199 } 1200 1201 if (spec.field_width > 0) 1202 len = min_t(int, spec.field_width, 64); 1203 1204 for (i = 0; i < len; ++i) { 1205 if (buf < end) 1206 *buf = hex_asc_hi(addr[i]); 1207 ++buf; 1208 if (buf < end) 1209 *buf = hex_asc_lo(addr[i]); 1210 ++buf; 1211 1212 if (separator && i != len - 1) { 1213 if (buf < end) 1214 *buf = separator; 1215 ++buf; 1216 } 1217 } 1218 1219 return buf; 1220 } 1221 1222 static noinline_for_stack 1223 char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, 1224 struct printf_spec spec, const char *fmt) 1225 { 1226 const int CHUNKSZ = 32; 1227 int nr_bits = max_t(int, spec.field_width, 0); 1228 int i, chunksz; 1229 bool first = true; 1230 1231 if (check_pointer(&buf, end, bitmap, spec)) 1232 return buf; 1233 1234 /* reused to print numbers */ 1235 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1236 1237 chunksz = nr_bits & (CHUNKSZ - 1); 1238 if (chunksz == 0) 1239 chunksz = CHUNKSZ; 1240 1241 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1242 for (; i >= 0; i -= CHUNKSZ) { 1243 u32 chunkmask, val; 1244 int word, bit; 1245 1246 chunkmask = ((1ULL << chunksz) - 1); 1247 word = i / BITS_PER_LONG; 1248 bit = i % BITS_PER_LONG; 1249 val = (bitmap[word] >> bit) & chunkmask; 1250 1251 if (!first) { 1252 if (buf < end) 1253 *buf = ','; 1254 buf++; 1255 } 1256 first = false; 1257 1258 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1259 buf = number(buf, end, val, spec); 1260 1261 chunksz = CHUNKSZ; 1262 } 1263 return buf; 1264 } 1265 1266 static noinline_for_stack 1267 char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, 1268 struct printf_spec spec, const char *fmt) 1269 { 1270 int nr_bits = max_t(int, spec.field_width, 0); 1271 bool first = true; 1272 int rbot, rtop; 1273 1274 if (check_pointer(&buf, end, bitmap, spec)) 1275 return buf; 1276 1277 for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { 1278 if (!first) { 1279 if (buf < end) 1280 *buf = ','; 1281 buf++; 1282 } 1283 first = false; 1284 1285 buf = number(buf, end, rbot, default_dec_spec); 1286 if (rtop == rbot + 1) 1287 continue; 1288 1289 if (buf < end) 1290 *buf = '-'; 1291 buf = number(++buf, end, rtop - 1, default_dec_spec); 1292 } 1293 return buf; 1294 } 1295 1296 static noinline_for_stack 1297 char *mac_address_string(char *buf, char *end, u8 *addr, 1298 struct printf_spec spec, const char *fmt) 1299 { 1300 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1301 char *p = mac_addr; 1302 int i; 1303 char separator; 1304 bool reversed = false; 1305 1306 if (check_pointer(&buf, end, addr, spec)) 1307 return buf; 1308 1309 switch (fmt[1]) { 1310 case 'F': 1311 separator = '-'; 1312 break; 1313 1314 case 'R': 1315 reversed = true; 1316 fallthrough; 1317 1318 default: 1319 separator = ':'; 1320 break; 1321 } 1322 1323 for (i = 0; i < 6; i++) { 1324 if (reversed) 1325 p = hex_byte_pack(p, addr[5 - i]); 1326 else 1327 p = hex_byte_pack(p, addr[i]); 1328 1329 if (fmt[0] == 'M' && i != 5) 1330 *p++ = separator; 1331 } 1332 *p = '\0'; 1333 1334 return string_nocheck(buf, end, mac_addr, spec); 1335 } 1336 1337 static noinline_for_stack 1338 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1339 { 1340 int i; 1341 bool leading_zeros = (fmt[0] == 'i'); 1342 int index; 1343 int step; 1344 1345 switch (fmt[2]) { 1346 case 'h': 1347 #ifdef __BIG_ENDIAN 1348 index = 0; 1349 step = 1; 1350 #else 1351 index = 3; 1352 step = -1; 1353 #endif 1354 break; 1355 case 'l': 1356 index = 3; 1357 step = -1; 1358 break; 1359 case 'n': 1360 case 'b': 1361 default: 1362 index = 0; 1363 step = 1; 1364 break; 1365 } 1366 for (i = 0; i < 4; i++) { 1367 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1368 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1369 if (leading_zeros) { 1370 if (digits < 3) 1371 *p++ = '0'; 1372 if (digits < 2) 1373 *p++ = '0'; 1374 } 1375 /* reverse the digits in the quad */ 1376 while (digits--) 1377 *p++ = temp[digits]; 1378 if (i < 3) 1379 *p++ = '.'; 1380 index += step; 1381 } 1382 *p = '\0'; 1383 1384 return p; 1385 } 1386 1387 static noinline_for_stack 1388 char *ip6_compressed_string(char *p, const char *addr) 1389 { 1390 int i, j, range; 1391 unsigned char zerolength[8]; 1392 int longest = 1; 1393 int colonpos = -1; 1394 u16 word; 1395 u8 hi, lo; 1396 bool needcolon = false; 1397 bool useIPv4; 1398 struct in6_addr in6; 1399 1400 memcpy(&in6, addr, sizeof(struct in6_addr)); 1401 1402 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1403 1404 memset(zerolength, 0, sizeof(zerolength)); 1405 1406 if (useIPv4) 1407 range = 6; 1408 else 1409 range = 8; 1410 1411 /* find position of longest 0 run */ 1412 for (i = 0; i < range; i++) { 1413 for (j = i; j < range; j++) { 1414 if (in6.s6_addr16[j] != 0) 1415 break; 1416 zerolength[i]++; 1417 } 1418 } 1419 for (i = 0; i < range; i++) { 1420 if (zerolength[i] > longest) { 1421 longest = zerolength[i]; 1422 colonpos = i; 1423 } 1424 } 1425 if (longest == 1) /* don't compress a single 0 */ 1426 colonpos = -1; 1427 1428 /* emit address */ 1429 for (i = 0; i < range; i++) { 1430 if (i == colonpos) { 1431 if (needcolon || i == 0) 1432 *p++ = ':'; 1433 *p++ = ':'; 1434 needcolon = false; 1435 i += longest - 1; 1436 continue; 1437 } 1438 if (needcolon) { 1439 *p++ = ':'; 1440 needcolon = false; 1441 } 1442 /* hex u16 without leading 0s */ 1443 word = ntohs(in6.s6_addr16[i]); 1444 hi = word >> 8; 1445 lo = word & 0xff; 1446 if (hi) { 1447 if (hi > 0x0f) 1448 p = hex_byte_pack(p, hi); 1449 else 1450 *p++ = hex_asc_lo(hi); 1451 p = hex_byte_pack(p, lo); 1452 } 1453 else if (lo > 0x0f) 1454 p = hex_byte_pack(p, lo); 1455 else 1456 *p++ = hex_asc_lo(lo); 1457 needcolon = true; 1458 } 1459 1460 if (useIPv4) { 1461 if (needcolon) 1462 *p++ = ':'; 1463 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1464 } 1465 *p = '\0'; 1466 1467 return p; 1468 } 1469 1470 static noinline_for_stack 1471 char *ip6_string(char *p, const char *addr, const char *fmt) 1472 { 1473 int i; 1474 1475 for (i = 0; i < 8; i++) { 1476 p = hex_byte_pack(p, *addr++); 1477 p = hex_byte_pack(p, *addr++); 1478 if (fmt[0] == 'I' && i != 7) 1479 *p++ = ':'; 1480 } 1481 *p = '\0'; 1482 1483 return p; 1484 } 1485 1486 static noinline_for_stack 1487 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1488 struct printf_spec spec, const char *fmt) 1489 { 1490 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1491 1492 if (fmt[0] == 'I' && fmt[2] == 'c') 1493 ip6_compressed_string(ip6_addr, addr); 1494 else 1495 ip6_string(ip6_addr, addr, fmt); 1496 1497 return string_nocheck(buf, end, ip6_addr, spec); 1498 } 1499 1500 static noinline_for_stack 1501 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1502 struct printf_spec spec, const char *fmt) 1503 { 1504 char ip4_addr[sizeof("255.255.255.255")]; 1505 1506 ip4_string(ip4_addr, addr, fmt); 1507 1508 return string_nocheck(buf, end, ip4_addr, spec); 1509 } 1510 1511 static noinline_for_stack 1512 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1513 struct printf_spec spec, const char *fmt) 1514 { 1515 bool have_p = false, have_s = false, have_f = false, have_c = false; 1516 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1517 sizeof(":12345") + sizeof("/123456789") + 1518 sizeof("%1234567890")]; 1519 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1520 const u8 *addr = (const u8 *) &sa->sin6_addr; 1521 char fmt6[2] = { fmt[0], '6' }; 1522 u8 off = 0; 1523 1524 fmt++; 1525 while (isalpha(*++fmt)) { 1526 switch (*fmt) { 1527 case 'p': 1528 have_p = true; 1529 break; 1530 case 'f': 1531 have_f = true; 1532 break; 1533 case 's': 1534 have_s = true; 1535 break; 1536 case 'c': 1537 have_c = true; 1538 break; 1539 } 1540 } 1541 1542 if (have_p || have_s || have_f) { 1543 *p = '['; 1544 off = 1; 1545 } 1546 1547 if (fmt6[0] == 'I' && have_c) 1548 p = ip6_compressed_string(ip6_addr + off, addr); 1549 else 1550 p = ip6_string(ip6_addr + off, addr, fmt6); 1551 1552 if (have_p || have_s || have_f) 1553 *p++ = ']'; 1554 1555 if (have_p) { 1556 *p++ = ':'; 1557 p = number(p, pend, ntohs(sa->sin6_port), spec); 1558 } 1559 if (have_f) { 1560 *p++ = '/'; 1561 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1562 IPV6_FLOWINFO_MASK), spec); 1563 } 1564 if (have_s) { 1565 *p++ = '%'; 1566 p = number(p, pend, sa->sin6_scope_id, spec); 1567 } 1568 *p = '\0'; 1569 1570 return string_nocheck(buf, end, ip6_addr, spec); 1571 } 1572 1573 static noinline_for_stack 1574 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1575 struct printf_spec spec, const char *fmt) 1576 { 1577 bool have_p = false; 1578 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1579 char *pend = ip4_addr + sizeof(ip4_addr); 1580 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1581 char fmt4[3] = { fmt[0], '4', 0 }; 1582 1583 fmt++; 1584 while (isalpha(*++fmt)) { 1585 switch (*fmt) { 1586 case 'p': 1587 have_p = true; 1588 break; 1589 case 'h': 1590 case 'l': 1591 case 'n': 1592 case 'b': 1593 fmt4[2] = *fmt; 1594 break; 1595 } 1596 } 1597 1598 p = ip4_string(ip4_addr, addr, fmt4); 1599 if (have_p) { 1600 *p++ = ':'; 1601 p = number(p, pend, ntohs(sa->sin_port), spec); 1602 } 1603 *p = '\0'; 1604 1605 return string_nocheck(buf, end, ip4_addr, spec); 1606 } 1607 1608 static noinline_for_stack 1609 char *ip_addr_string(char *buf, char *end, const void *ptr, 1610 struct printf_spec spec, const char *fmt) 1611 { 1612 char *err_fmt_msg; 1613 1614 if (check_pointer(&buf, end, ptr, spec)) 1615 return buf; 1616 1617 switch (fmt[1]) { 1618 case '6': 1619 return ip6_addr_string(buf, end, ptr, spec, fmt); 1620 case '4': 1621 return ip4_addr_string(buf, end, ptr, spec, fmt); 1622 case 'S': { 1623 const union { 1624 struct sockaddr raw; 1625 struct sockaddr_in v4; 1626 struct sockaddr_in6 v6; 1627 } *sa = ptr; 1628 1629 switch (sa->raw.sa_family) { 1630 case AF_INET: 1631 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1632 case AF_INET6: 1633 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1634 default: 1635 return error_string(buf, end, "(einval)", spec); 1636 }} 1637 } 1638 1639 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1640 return error_string(buf, end, err_fmt_msg, spec); 1641 } 1642 1643 static noinline_for_stack 1644 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1645 const char *fmt) 1646 { 1647 bool found = true; 1648 int count = 1; 1649 unsigned int flags = 0; 1650 int len; 1651 1652 if (spec.field_width == 0) 1653 return buf; /* nothing to print */ 1654 1655 if (check_pointer(&buf, end, addr, spec)) 1656 return buf; 1657 1658 do { 1659 switch (fmt[count++]) { 1660 case 'a': 1661 flags |= ESCAPE_ANY; 1662 break; 1663 case 'c': 1664 flags |= ESCAPE_SPECIAL; 1665 break; 1666 case 'h': 1667 flags |= ESCAPE_HEX; 1668 break; 1669 case 'n': 1670 flags |= ESCAPE_NULL; 1671 break; 1672 case 'o': 1673 flags |= ESCAPE_OCTAL; 1674 break; 1675 case 'p': 1676 flags |= ESCAPE_NP; 1677 break; 1678 case 's': 1679 flags |= ESCAPE_SPACE; 1680 break; 1681 default: 1682 found = false; 1683 break; 1684 } 1685 } while (found); 1686 1687 if (!flags) 1688 flags = ESCAPE_ANY_NP; 1689 1690 len = spec.field_width < 0 ? 1 : spec.field_width; 1691 1692 /* 1693 * string_escape_mem() writes as many characters as it can to 1694 * the given buffer, and returns the total size of the output 1695 * had the buffer been big enough. 1696 */ 1697 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1698 1699 return buf; 1700 } 1701 1702 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1703 struct printf_spec spec, const char *fmt) 1704 { 1705 va_list va; 1706 1707 if (check_pointer(&buf, end, va_fmt, spec)) 1708 return buf; 1709 1710 va_copy(va, *va_fmt->va); 1711 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1712 va_end(va); 1713 1714 return buf; 1715 } 1716 1717 static noinline_for_stack 1718 char *uuid_string(char *buf, char *end, const u8 *addr, 1719 struct printf_spec spec, const char *fmt) 1720 { 1721 char uuid[UUID_STRING_LEN + 1]; 1722 char *p = uuid; 1723 int i; 1724 const u8 *index = uuid_index; 1725 bool uc = false; 1726 1727 if (check_pointer(&buf, end, addr, spec)) 1728 return buf; 1729 1730 switch (*(++fmt)) { 1731 case 'L': 1732 uc = true; 1733 fallthrough; 1734 case 'l': 1735 index = guid_index; 1736 break; 1737 case 'B': 1738 uc = true; 1739 break; 1740 } 1741 1742 for (i = 0; i < 16; i++) { 1743 if (uc) 1744 p = hex_byte_pack_upper(p, addr[index[i]]); 1745 else 1746 p = hex_byte_pack(p, addr[index[i]]); 1747 switch (i) { 1748 case 3: 1749 case 5: 1750 case 7: 1751 case 9: 1752 *p++ = '-'; 1753 break; 1754 } 1755 } 1756 1757 *p = 0; 1758 1759 return string_nocheck(buf, end, uuid, spec); 1760 } 1761 1762 static noinline_for_stack 1763 char *netdev_bits(char *buf, char *end, const void *addr, 1764 struct printf_spec spec, const char *fmt) 1765 { 1766 unsigned long long num; 1767 int size; 1768 1769 if (check_pointer(&buf, end, addr, spec)) 1770 return buf; 1771 1772 switch (fmt[1]) { 1773 case 'F': 1774 num = *(const netdev_features_t *)addr; 1775 size = sizeof(netdev_features_t); 1776 break; 1777 default: 1778 return error_string(buf, end, "(%pN?)", spec); 1779 } 1780 1781 return special_hex_number(buf, end, num, size); 1782 } 1783 1784 static noinline_for_stack 1785 char *fourcc_string(char *buf, char *end, const u32 *fourcc, 1786 struct printf_spec spec, const char *fmt) 1787 { 1788 char output[sizeof("0123 little-endian (0x01234567)")]; 1789 char *p = output; 1790 unsigned int i; 1791 u32 orig, val; 1792 1793 if (fmt[1] != 'c' || fmt[2] != 'c') 1794 return error_string(buf, end, "(%p4?)", spec); 1795 1796 if (check_pointer(&buf, end, fourcc, spec)) 1797 return buf; 1798 1799 orig = get_unaligned(fourcc); 1800 val = orig & ~BIT(31); 1801 1802 for (i = 0; i < sizeof(u32); i++) { 1803 unsigned char c = val >> (i * 8); 1804 1805 /* Print non-control ASCII characters as-is, dot otherwise */ 1806 *p++ = isascii(c) && isprint(c) ? c : '.'; 1807 } 1808 1809 *p++ = ' '; 1810 strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); 1811 p += strlen(p); 1812 1813 *p++ = ' '; 1814 *p++ = '('; 1815 p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); 1816 *p++ = ')'; 1817 *p = '\0'; 1818 1819 return string(buf, end, output, spec); 1820 } 1821 1822 static noinline_for_stack 1823 char *address_val(char *buf, char *end, const void *addr, 1824 struct printf_spec spec, const char *fmt) 1825 { 1826 unsigned long long num; 1827 int size; 1828 1829 if (check_pointer(&buf, end, addr, spec)) 1830 return buf; 1831 1832 switch (fmt[1]) { 1833 case 'd': 1834 num = *(const dma_addr_t *)addr; 1835 size = sizeof(dma_addr_t); 1836 break; 1837 case 'p': 1838 default: 1839 num = *(const phys_addr_t *)addr; 1840 size = sizeof(phys_addr_t); 1841 break; 1842 } 1843 1844 return special_hex_number(buf, end, num, size); 1845 } 1846 1847 static noinline_for_stack 1848 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1849 { 1850 int year = tm->tm_year + (r ? 0 : 1900); 1851 int mon = tm->tm_mon + (r ? 0 : 1); 1852 1853 buf = number(buf, end, year, default_dec04_spec); 1854 if (buf < end) 1855 *buf = '-'; 1856 buf++; 1857 1858 buf = number(buf, end, mon, default_dec02_spec); 1859 if (buf < end) 1860 *buf = '-'; 1861 buf++; 1862 1863 return number(buf, end, tm->tm_mday, default_dec02_spec); 1864 } 1865 1866 static noinline_for_stack 1867 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1868 { 1869 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1870 if (buf < end) 1871 *buf = ':'; 1872 buf++; 1873 1874 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1875 if (buf < end) 1876 *buf = ':'; 1877 buf++; 1878 1879 return number(buf, end, tm->tm_sec, default_dec02_spec); 1880 } 1881 1882 static noinline_for_stack 1883 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1884 struct printf_spec spec, const char *fmt) 1885 { 1886 bool have_t = true, have_d = true; 1887 bool raw = false, iso8601_separator = true; 1888 bool found = true; 1889 int count = 2; 1890 1891 if (check_pointer(&buf, end, tm, spec)) 1892 return buf; 1893 1894 switch (fmt[count]) { 1895 case 'd': 1896 have_t = false; 1897 count++; 1898 break; 1899 case 't': 1900 have_d = false; 1901 count++; 1902 break; 1903 } 1904 1905 do { 1906 switch (fmt[count++]) { 1907 case 'r': 1908 raw = true; 1909 break; 1910 case 's': 1911 iso8601_separator = false; 1912 break; 1913 default: 1914 found = false; 1915 break; 1916 } 1917 } while (found); 1918 1919 if (have_d) 1920 buf = date_str(buf, end, tm, raw); 1921 if (have_d && have_t) { 1922 if (buf < end) 1923 *buf = iso8601_separator ? 'T' : ' '; 1924 buf++; 1925 } 1926 if (have_t) 1927 buf = time_str(buf, end, tm, raw); 1928 1929 return buf; 1930 } 1931 1932 static noinline_for_stack 1933 char *time64_str(char *buf, char *end, const time64_t time, 1934 struct printf_spec spec, const char *fmt) 1935 { 1936 struct rtc_time rtc_time; 1937 struct tm tm; 1938 1939 time64_to_tm(time, 0, &tm); 1940 1941 rtc_time.tm_sec = tm.tm_sec; 1942 rtc_time.tm_min = tm.tm_min; 1943 rtc_time.tm_hour = tm.tm_hour; 1944 rtc_time.tm_mday = tm.tm_mday; 1945 rtc_time.tm_mon = tm.tm_mon; 1946 rtc_time.tm_year = tm.tm_year; 1947 rtc_time.tm_wday = tm.tm_wday; 1948 rtc_time.tm_yday = tm.tm_yday; 1949 1950 rtc_time.tm_isdst = 0; 1951 1952 return rtc_str(buf, end, &rtc_time, spec, fmt); 1953 } 1954 1955 static noinline_for_stack 1956 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1957 const char *fmt) 1958 { 1959 switch (fmt[1]) { 1960 case 'R': 1961 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1962 case 'T': 1963 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); 1964 default: 1965 return error_string(buf, end, "(%pt?)", spec); 1966 } 1967 } 1968 1969 static noinline_for_stack 1970 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1971 const char *fmt) 1972 { 1973 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1974 return error_string(buf, end, "(%pC?)", spec); 1975 1976 if (check_pointer(&buf, end, clk, spec)) 1977 return buf; 1978 1979 switch (fmt[1]) { 1980 case 'n': 1981 default: 1982 #ifdef CONFIG_COMMON_CLK 1983 return string(buf, end, __clk_get_name(clk), spec); 1984 #else 1985 return ptr_to_id(buf, end, clk, spec); 1986 #endif 1987 } 1988 } 1989 1990 static 1991 char *format_flags(char *buf, char *end, unsigned long flags, 1992 const struct trace_print_flags *names) 1993 { 1994 unsigned long mask; 1995 1996 for ( ; flags && names->name; names++) { 1997 mask = names->mask; 1998 if ((flags & mask) != mask) 1999 continue; 2000 2001 buf = string(buf, end, names->name, default_str_spec); 2002 2003 flags &= ~mask; 2004 if (flags) { 2005 if (buf < end) 2006 *buf = '|'; 2007 buf++; 2008 } 2009 } 2010 2011 if (flags) 2012 buf = number(buf, end, flags, default_flag_spec); 2013 2014 return buf; 2015 } 2016 2017 struct page_flags_fields { 2018 int width; 2019 int shift; 2020 int mask; 2021 const struct printf_spec *spec; 2022 const char *name; 2023 }; 2024 2025 static const struct page_flags_fields pff[] = { 2026 {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, 2027 &default_dec_spec, "section"}, 2028 {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, 2029 &default_dec_spec, "node"}, 2030 {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, 2031 &default_dec_spec, "zone"}, 2032 {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, 2033 &default_flag_spec, "lastcpupid"}, 2034 {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, 2035 &default_flag_spec, "kasantag"}, 2036 }; 2037 2038 static 2039 char *format_page_flags(char *buf, char *end, unsigned long flags) 2040 { 2041 unsigned long main_flags = flags & PAGEFLAGS_MASK; 2042 bool append = false; 2043 int i; 2044 2045 buf = number(buf, end, flags, default_flag_spec); 2046 if (buf < end) 2047 *buf = '('; 2048 buf++; 2049 2050 /* Page flags from the main area. */ 2051 if (main_flags) { 2052 buf = format_flags(buf, end, main_flags, pageflag_names); 2053 append = true; 2054 } 2055 2056 /* Page flags from the fields area */ 2057 for (i = 0; i < ARRAY_SIZE(pff); i++) { 2058 /* Skip undefined fields. */ 2059 if (!pff[i].width) 2060 continue; 2061 2062 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ 2063 if (append) { 2064 if (buf < end) 2065 *buf = '|'; 2066 buf++; 2067 } 2068 2069 buf = string(buf, end, pff[i].name, default_str_spec); 2070 if (buf < end) 2071 *buf = '='; 2072 buf++; 2073 buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, 2074 *pff[i].spec); 2075 2076 append = true; 2077 } 2078 if (buf < end) 2079 *buf = ')'; 2080 buf++; 2081 2082 return buf; 2083 } 2084 2085 static noinline_for_stack 2086 char *flags_string(char *buf, char *end, void *flags_ptr, 2087 struct printf_spec spec, const char *fmt) 2088 { 2089 unsigned long flags; 2090 const struct trace_print_flags *names; 2091 2092 if (check_pointer(&buf, end, flags_ptr, spec)) 2093 return buf; 2094 2095 switch (fmt[1]) { 2096 case 'p': 2097 return format_page_flags(buf, end, *(unsigned long *)flags_ptr); 2098 case 'v': 2099 flags = *(unsigned long *)flags_ptr; 2100 names = vmaflag_names; 2101 break; 2102 case 'g': 2103 flags = (__force unsigned long)(*(gfp_t *)flags_ptr); 2104 names = gfpflag_names; 2105 break; 2106 default: 2107 return error_string(buf, end, "(%pG?)", spec); 2108 } 2109 2110 return format_flags(buf, end, flags, names); 2111 } 2112 2113 static noinline_for_stack 2114 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, 2115 char *end) 2116 { 2117 int depth; 2118 2119 /* Loop starting from the root node to the current node. */ 2120 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { 2121 /* 2122 * Only get a reference for other nodes (i.e. parent nodes). 2123 * fwnode refcount may be 0 here. 2124 */ 2125 struct fwnode_handle *__fwnode = depth ? 2126 fwnode_get_nth_parent(fwnode, depth) : fwnode; 2127 2128 buf = string(buf, end, fwnode_get_name_prefix(__fwnode), 2129 default_str_spec); 2130 buf = string(buf, end, fwnode_get_name(__fwnode), 2131 default_str_spec); 2132 2133 if (depth) 2134 fwnode_handle_put(__fwnode); 2135 } 2136 2137 return buf; 2138 } 2139 2140 static noinline_for_stack 2141 char *device_node_string(char *buf, char *end, struct device_node *dn, 2142 struct printf_spec spec, const char *fmt) 2143 { 2144 char tbuf[sizeof("xxxx") + 1]; 2145 const char *p; 2146 int ret; 2147 char *buf_start = buf; 2148 struct property *prop; 2149 bool has_mult, pass; 2150 2151 struct printf_spec str_spec = spec; 2152 str_spec.field_width = -1; 2153 2154 if (fmt[0] != 'F') 2155 return error_string(buf, end, "(%pO?)", spec); 2156 2157 if (!IS_ENABLED(CONFIG_OF)) 2158 return error_string(buf, end, "(%pOF?)", spec); 2159 2160 if (check_pointer(&buf, end, dn, spec)) 2161 return buf; 2162 2163 /* simple case without anything any more format specifiers */ 2164 fmt++; 2165 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 2166 fmt = "f"; 2167 2168 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 2169 int precision; 2170 if (pass) { 2171 if (buf < end) 2172 *buf = ':'; 2173 buf++; 2174 } 2175 2176 switch (*fmt) { 2177 case 'f': /* full_name */ 2178 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, 2179 end); 2180 break; 2181 case 'n': /* name */ 2182 p = fwnode_get_name(of_fwnode_handle(dn)); 2183 precision = str_spec.precision; 2184 str_spec.precision = strchrnul(p, '@') - p; 2185 buf = string(buf, end, p, str_spec); 2186 str_spec.precision = precision; 2187 break; 2188 case 'p': /* phandle */ 2189 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); 2190 break; 2191 case 'P': /* path-spec */ 2192 p = fwnode_get_name(of_fwnode_handle(dn)); 2193 if (!p[1]) 2194 p = "/"; 2195 buf = string(buf, end, p, str_spec); 2196 break; 2197 case 'F': /* flags */ 2198 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 2199 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 2200 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 2201 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 2202 tbuf[4] = 0; 2203 buf = string_nocheck(buf, end, tbuf, str_spec); 2204 break; 2205 case 'c': /* major compatible string */ 2206 ret = of_property_read_string(dn, "compatible", &p); 2207 if (!ret) 2208 buf = string(buf, end, p, str_spec); 2209 break; 2210 case 'C': /* full compatible string */ 2211 has_mult = false; 2212 of_property_for_each_string(dn, "compatible", prop, p) { 2213 if (has_mult) 2214 buf = string_nocheck(buf, end, ",", str_spec); 2215 buf = string_nocheck(buf, end, "\"", str_spec); 2216 buf = string(buf, end, p, str_spec); 2217 buf = string_nocheck(buf, end, "\"", str_spec); 2218 2219 has_mult = true; 2220 } 2221 break; 2222 default: 2223 break; 2224 } 2225 } 2226 2227 return widen_string(buf, buf - buf_start, end, spec); 2228 } 2229 2230 static noinline_for_stack 2231 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, 2232 struct printf_spec spec, const char *fmt) 2233 { 2234 struct printf_spec str_spec = spec; 2235 char *buf_start = buf; 2236 2237 str_spec.field_width = -1; 2238 2239 if (*fmt != 'w') 2240 return error_string(buf, end, "(%pf?)", spec); 2241 2242 if (check_pointer(&buf, end, fwnode, spec)) 2243 return buf; 2244 2245 fmt++; 2246 2247 switch (*fmt) { 2248 case 'P': /* name */ 2249 buf = string(buf, end, fwnode_get_name(fwnode), str_spec); 2250 break; 2251 case 'f': /* full_name */ 2252 default: 2253 buf = fwnode_full_name_string(fwnode, buf, end); 2254 break; 2255 } 2256 2257 return widen_string(buf, buf - buf_start, end, spec); 2258 } 2259 2260 static noinline_for_stack 2261 char *resource_or_range(const char *fmt, char *buf, char *end, void *ptr, 2262 struct printf_spec spec) 2263 { 2264 if (*fmt == 'r' && fmt[1] == 'a') 2265 return range_string(buf, end, ptr, spec, fmt); 2266 return resource_string(buf, end, ptr, spec, fmt); 2267 } 2268 2269 int __init no_hash_pointers_enable(char *str) 2270 { 2271 if (no_hash_pointers) 2272 return 0; 2273 2274 no_hash_pointers = true; 2275 2276 pr_warn("**********************************************************\n"); 2277 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2278 pr_warn("** **\n"); 2279 pr_warn("** This system shows unhashed kernel memory addresses **\n"); 2280 pr_warn("** via the console, logs, and other interfaces. This **\n"); 2281 pr_warn("** might reduce the security of your system. **\n"); 2282 pr_warn("** **\n"); 2283 pr_warn("** If you see this message and you are not debugging **\n"); 2284 pr_warn("** the kernel, report this immediately to your system **\n"); 2285 pr_warn("** administrator! **\n"); 2286 pr_warn("** **\n"); 2287 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); 2288 pr_warn("**********************************************************\n"); 2289 2290 return 0; 2291 } 2292 early_param("no_hash_pointers", no_hash_pointers_enable); 2293 2294 /* 2295 * Show a '%p' thing. A kernel extension is that the '%p' is followed 2296 * by an extra set of alphanumeric characters that are extended format 2297 * specifiers. 2298 * 2299 * Please update scripts/checkpatch.pl when adding/removing conversion 2300 * characters. (Search for "check for vsprintf extension"). 2301 * 2302 * Right now we handle: 2303 * 2304 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2305 * - 's' For symbolic direct pointers (or function descriptors) without offset 2306 * - '[Ss]R' as above with __builtin_extract_return_addr() translation 2307 * - 'S[R]b' as above with module build ID (for use in backtraces) 2308 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of 2309 * %ps and %pS. Be careful when re-using these specifiers. 2310 * - 'B' For backtraced symbolic direct pointers with offset 2311 * - 'Bb' as above with module build ID (for use in backtraces) 2312 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2313 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2314 * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] 2315 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2316 * width which must be explicitly specified either as part of the 2317 * format string '%32b[l]' or through '%*b[l]', [l] selects 2318 * range-list format instead of hex format 2319 * - 'M' For a 6-byte MAC address, it prints the address in the 2320 * usual colon-separated hex notation 2321 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2322 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2323 * with a dash-separated hex notation 2324 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2325 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2326 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2327 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2328 * [S][pfs] 2329 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2330 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2331 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2332 * IPv6 omits the colons (01020304...0f) 2333 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2334 * [S][pfs] 2335 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2336 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2337 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2338 * - 'I[6S]c' for IPv6 addresses printed as specified by 2339 * https://tools.ietf.org/html/rfc5952 2340 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2341 * of the following flags (see string_escape_mem() for the 2342 * details): 2343 * a - ESCAPE_ANY 2344 * c - ESCAPE_SPECIAL 2345 * h - ESCAPE_HEX 2346 * n - ESCAPE_NULL 2347 * o - ESCAPE_OCTAL 2348 * p - ESCAPE_NP 2349 * s - ESCAPE_SPACE 2350 * By default ESCAPE_ANY_NP is used. 2351 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2352 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2353 * Options for %pU are: 2354 * b big endian lower case hex (default) 2355 * B big endian UPPER case hex 2356 * l little endian lower case hex 2357 * L little endian UPPER case hex 2358 * big endian output byte order is: 2359 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2360 * little endian output byte order is: 2361 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2362 * - 'V' For a struct va_format which contains a format string * and va_list *, 2363 * call vsnprintf(->format, *->va_list). 2364 * Implements a "recursive vsnprintf". 2365 * Do not use this feature without some mechanism to verify the 2366 * correctness of the format string and va_list arguments. 2367 * - 'K' For a kernel pointer that should be hidden from unprivileged users. 2368 * Use only for procfs, sysfs and similar files, not printk(); please 2369 * read the documentation (path below) first. 2370 * - 'NF' For a netdev_features_t 2371 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. 2372 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2373 * a certain separator (' ' by default): 2374 * C colon 2375 * D dash 2376 * N no separator 2377 * The maximum supported length is 64 bytes of the input. Consider 2378 * to use print_hex_dump() for the larger input. 2379 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2380 * (default assumed to be phys_addr_t, passed by reference) 2381 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2382 * - 'D[234]' Same as 'd' but for a struct file 2383 * - 'g' For block_device name (gendisk + partition number) 2384 * - 't[RT][dt][r][s]' For time and date as represented by: 2385 * R struct rtc_time 2386 * T time64_t 2387 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2388 * (legacy clock framework) of the clock 2389 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2390 * (legacy clock framework) of the clock 2391 * - 'G' For flags to be printed as a collection of symbolic strings that would 2392 * construct the specific value. Supported flags given by option: 2393 * p page flags (see struct page) given as pointer to unsigned long 2394 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2395 * v vma flags (VM_*) given as pointer to unsigned long 2396 * - 'OF[fnpPcCF]' For a device tree object 2397 * Without any optional arguments prints the full_name 2398 * f device node full_name 2399 * n device node name 2400 * p device node phandle 2401 * P device node path spec (name + @unit) 2402 * F device node flags 2403 * c major compatible string 2404 * C full compatible string 2405 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer 2406 * Without an option prints the full name of the node 2407 * f full name 2408 * P node name, including a possible unit address 2409 * - 'x' For printing the address unmodified. Equivalent to "%lx". 2410 * Please read the documentation (path below) before using! 2411 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of 2412 * bpf_trace_printk() where [ku] prefix specifies either kernel (k) 2413 * or user (u) memory to probe, and: 2414 * s a string, equivalent to "%s" on direct vsnprintf() use 2415 * 2416 * ** When making changes please also update: 2417 * Documentation/core-api/printk-formats.rst 2418 * 2419 * Note: The default behaviour (unadorned %p) is to hash the address, 2420 * rendering it useful as a unique identifier. 2421 * 2422 * There is also a '%pA' format specifier, but it is only intended to be used 2423 * from Rust code to format core::fmt::Arguments. Do *not* use it from C. 2424 * See rust/kernel/print.rs for details. 2425 */ 2426 static noinline_for_stack 2427 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2428 struct printf_spec spec) 2429 { 2430 switch (*fmt) { 2431 case 'S': 2432 case 's': 2433 ptr = dereference_symbol_descriptor(ptr); 2434 fallthrough; 2435 case 'B': 2436 return symbol_string(buf, end, ptr, spec, fmt); 2437 case 'R': 2438 case 'r': 2439 return resource_or_range(fmt, buf, end, ptr, spec); 2440 case 'h': 2441 return hex_string(buf, end, ptr, spec, fmt); 2442 case 'b': 2443 switch (fmt[1]) { 2444 case 'l': 2445 return bitmap_list_string(buf, end, ptr, spec, fmt); 2446 default: 2447 return bitmap_string(buf, end, ptr, spec, fmt); 2448 } 2449 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2450 case 'm': /* Contiguous: 000102030405 */ 2451 /* [mM]F (FDDI) */ 2452 /* [mM]R (Reverse order; Bluetooth) */ 2453 return mac_address_string(buf, end, ptr, spec, fmt); 2454 case 'I': /* Formatted IP supported 2455 * 4: 1.2.3.4 2456 * 6: 0001:0203:...:0708 2457 * 6c: 1::708 or 1::1.2.3.4 2458 */ 2459 case 'i': /* Contiguous: 2460 * 4: 001.002.003.004 2461 * 6: 000102...0f 2462 */ 2463 return ip_addr_string(buf, end, ptr, spec, fmt); 2464 case 'E': 2465 return escaped_string(buf, end, ptr, spec, fmt); 2466 case 'U': 2467 return uuid_string(buf, end, ptr, spec, fmt); 2468 case 'V': 2469 return va_format(buf, end, ptr, spec, fmt); 2470 case 'K': 2471 return restricted_pointer(buf, end, ptr, spec); 2472 case 'N': 2473 return netdev_bits(buf, end, ptr, spec, fmt); 2474 case '4': 2475 return fourcc_string(buf, end, ptr, spec, fmt); 2476 case 'a': 2477 return address_val(buf, end, ptr, spec, fmt); 2478 case 'd': 2479 return dentry_name(buf, end, ptr, spec, fmt); 2480 case 't': 2481 return time_and_date(buf, end, ptr, spec, fmt); 2482 case 'C': 2483 return clock(buf, end, ptr, spec, fmt); 2484 case 'D': 2485 return file_dentry_name(buf, end, ptr, spec, fmt); 2486 #ifdef CONFIG_BLOCK 2487 case 'g': 2488 return bdev_name(buf, end, ptr, spec, fmt); 2489 #endif 2490 2491 case 'G': 2492 return flags_string(buf, end, ptr, spec, fmt); 2493 case 'O': 2494 return device_node_string(buf, end, ptr, spec, fmt + 1); 2495 case 'f': 2496 return fwnode_string(buf, end, ptr, spec, fmt + 1); 2497 case 'A': 2498 if (!IS_ENABLED(CONFIG_RUST)) { 2499 WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); 2500 return error_string(buf, end, "(%pA?)", spec); 2501 } 2502 return rust_fmt_argument(buf, end, ptr); 2503 case 'x': 2504 return pointer_string(buf, end, ptr, spec); 2505 case 'e': 2506 /* %pe with a non-ERR_PTR gets treated as plain %p */ 2507 if (!IS_ERR(ptr)) 2508 return default_pointer(buf, end, ptr, spec); 2509 return err_ptr(buf, end, ptr, spec); 2510 case 'u': 2511 case 'k': 2512 switch (fmt[1]) { 2513 case 's': 2514 return string(buf, end, ptr, spec); 2515 default: 2516 return error_string(buf, end, "(einval)", spec); 2517 } 2518 default: 2519 return default_pointer(buf, end, ptr, spec); 2520 } 2521 } 2522 2523 struct fmt { 2524 const char *str; 2525 unsigned char state; // enum format_state 2526 unsigned char size; // size of numbers 2527 }; 2528 2529 #define SPEC_CHAR(x, flag) [(x)-32] = flag 2530 static unsigned char spec_flag(unsigned char c) 2531 { 2532 static const unsigned char spec_flag_array[] = { 2533 SPEC_CHAR(' ', SPACE), 2534 SPEC_CHAR('#', SPECIAL), 2535 SPEC_CHAR('+', PLUS), 2536 SPEC_CHAR('-', LEFT), 2537 SPEC_CHAR('0', ZEROPAD), 2538 }; 2539 c -= 32; 2540 return (c < sizeof(spec_flag_array)) ? spec_flag_array[c] : 0; 2541 } 2542 2543 /* 2544 * Helper function to decode printf style format. 2545 * Each call decode a token from the format and return the 2546 * number of characters read (or likely the delta where it wants 2547 * to go on the next call). 2548 * The decoded token is returned through the parameters 2549 * 2550 * 'h', 'l', or 'L' for integer fields 2551 * 'z' support added 23/7/1999 S.H. 2552 * 'z' changed to 'Z' --davidm 1/25/99 2553 * 'Z' changed to 'z' --adobriyan 2017-01-25 2554 * 't' added for ptrdiff_t 2555 * 2556 * @fmt: the format string 2557 * @type of the token returned 2558 * @flags: various flags such as +, -, # tokens.. 2559 * @field_width: overwritten width 2560 * @base: base of the number (octal, hex, ...) 2561 * @precision: precision of a number 2562 * @qualifier: qualifier of a number (long, size_t, ...) 2563 */ 2564 static noinline_for_stack 2565 struct fmt format_decode(struct fmt fmt, struct printf_spec *spec) 2566 { 2567 const char *start = fmt.str; 2568 char flag; 2569 2570 /* we finished early by reading the field width */ 2571 if (unlikely(fmt.state == FORMAT_STATE_WIDTH)) { 2572 if (spec->field_width < 0) { 2573 spec->field_width = -spec->field_width; 2574 spec->flags |= LEFT; 2575 } 2576 fmt.state = FORMAT_STATE_NONE; 2577 goto precision; 2578 } 2579 2580 /* we finished early by reading the precision */ 2581 if (unlikely(fmt.state == FORMAT_STATE_PRECISION)) { 2582 if (spec->precision < 0) 2583 spec->precision = 0; 2584 2585 fmt.state = FORMAT_STATE_NONE; 2586 goto qualifier; 2587 } 2588 2589 /* By default */ 2590 fmt.state = FORMAT_STATE_NONE; 2591 2592 for (; *fmt.str ; fmt.str++) { 2593 if (*fmt.str == '%') 2594 break; 2595 } 2596 2597 /* Return the current non-format string */ 2598 if (fmt.str != start || !*fmt.str) 2599 return fmt; 2600 2601 /* Process flags. This also skips the first '%' */ 2602 spec->flags = 0; 2603 do { 2604 /* this also skips first '%' */ 2605 flag = spec_flag(*++fmt.str); 2606 spec->flags |= flag; 2607 } while (flag); 2608 2609 /* get field width */ 2610 spec->field_width = -1; 2611 2612 if (isdigit(*fmt.str)) 2613 spec->field_width = skip_atoi(&fmt.str); 2614 else if (unlikely(*fmt.str == '*')) { 2615 /* it's the next argument */ 2616 fmt.state = FORMAT_STATE_WIDTH; 2617 fmt.str++; 2618 return fmt; 2619 } 2620 2621 precision: 2622 /* get the precision */ 2623 spec->precision = -1; 2624 if (unlikely(*fmt.str == '.')) { 2625 fmt.str++; 2626 if (isdigit(*fmt.str)) { 2627 spec->precision = skip_atoi(&fmt.str); 2628 if (spec->precision < 0) 2629 spec->precision = 0; 2630 } else if (*fmt.str == '*') { 2631 /* it's the next argument */ 2632 fmt.state = FORMAT_STATE_PRECISION; 2633 fmt.str++; 2634 return fmt; 2635 } 2636 } 2637 2638 qualifier: 2639 /* Set up default numeric format */ 2640 spec->base = 10; 2641 fmt.state = FORMAT_STATE_NUM; 2642 fmt.size = sizeof(int); 2643 static const struct format_state { 2644 unsigned char state; 2645 unsigned char size; 2646 unsigned char flags_or_double_size; 2647 unsigned char base; 2648 } lookup_state[256] = { 2649 // Length 2650 ['l'] = { 0, sizeof(long), sizeof(long long) }, 2651 ['L'] = { 0, sizeof(long long) }, 2652 ['h'] = { 0, sizeof(short), sizeof(char) }, 2653 ['H'] = { 0, sizeof(char) }, // Questionable historical 2654 ['z'] = { 0, sizeof(size_t) }, 2655 ['t'] = { 0, sizeof(ptrdiff_t) }, 2656 2657 // Non-numeric formats 2658 ['c'] = { FORMAT_STATE_CHAR }, 2659 ['s'] = { FORMAT_STATE_STR }, 2660 ['p'] = { FORMAT_STATE_PTR }, 2661 ['%'] = { FORMAT_STATE_PERCENT_CHAR }, 2662 2663 // Numerics 2664 ['o'] = { FORMAT_STATE_NUM, 0, 0, 8 }, 2665 ['x'] = { FORMAT_STATE_NUM, 0, SMALL, 16 }, 2666 ['X'] = { FORMAT_STATE_NUM, 0, 0, 16 }, 2667 ['d'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2668 ['i'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, 2669 ['u'] = { FORMAT_STATE_NUM, 0, 0, 10, }, 2670 2671 /* 2672 * Since %n poses a greater security risk than 2673 * utility, treat it as any other invalid or 2674 * unsupported format specifier. 2675 */ 2676 }; 2677 2678 const struct format_state *p = lookup_state + (u8)*fmt.str; 2679 if (p->size) { 2680 fmt.size = p->size; 2681 if (p->flags_or_double_size && fmt.str[0] == fmt.str[1]) { 2682 fmt.size = p->flags_or_double_size; 2683 fmt.str++; 2684 } 2685 fmt.str++; 2686 p = lookup_state + *fmt.str; 2687 } 2688 if (p->state) { 2689 if (p->base) 2690 spec->base = p->base; 2691 spec->flags |= p->flags_or_double_size; 2692 fmt.state = p->state; 2693 fmt.str++; 2694 return fmt; 2695 } 2696 2697 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt.str); 2698 fmt.state = FORMAT_STATE_INVALID; 2699 return fmt; 2700 } 2701 2702 static void 2703 set_field_width(struct printf_spec *spec, int width) 2704 { 2705 spec->field_width = width; 2706 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2707 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2708 } 2709 } 2710 2711 static void 2712 set_precision(struct printf_spec *spec, int prec) 2713 { 2714 spec->precision = prec; 2715 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2716 spec->precision = clamp(prec, 0, PRECISION_MAX); 2717 } 2718 } 2719 2720 /* 2721 * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate 2722 * as necessary and deal with signedness. 2723 * 2724 * 'size' is the size of the value in bytes. 2725 */ 2726 static unsigned long long convert_num_spec(unsigned int val, int size, struct printf_spec spec) 2727 { 2728 unsigned int shift = 32 - size*8; 2729 2730 val <<= shift; 2731 if (!(spec.flags & SIGN)) 2732 return val >> shift; 2733 return (int)val >> shift; 2734 } 2735 2736 /** 2737 * vsnprintf - Format a string and place it in a buffer 2738 * @buf: The buffer to place the result into 2739 * @size: The size of the buffer, including the trailing null space 2740 * @fmt_str: The format string to use 2741 * @args: Arguments for the format string 2742 * 2743 * This function generally follows C99 vsnprintf, but has some 2744 * extensions and a few limitations: 2745 * 2746 * - ``%n`` is unsupported 2747 * - ``%p*`` is handled by pointer() 2748 * 2749 * See pointer() or Documentation/core-api/printk-formats.rst for more 2750 * extensive description. 2751 * 2752 * **Please update the documentation in both places when making changes** 2753 * 2754 * The return value is the number of characters which would 2755 * be generated for the given input, excluding the trailing 2756 * '\0', as per ISO C99. If you want to have the exact 2757 * number of characters written into @buf as return value 2758 * (not including the trailing '\0'), use vscnprintf(). If the 2759 * return is greater than or equal to @size, the resulting 2760 * string is truncated. 2761 * 2762 * If you're not already dealing with a va_list consider using snprintf(). 2763 */ 2764 int vsnprintf(char *buf, size_t size, const char *fmt_str, va_list args) 2765 { 2766 char *str, *end; 2767 struct printf_spec spec = {0}; 2768 struct fmt fmt = { 2769 .str = fmt_str, 2770 .state = FORMAT_STATE_NONE, 2771 }; 2772 2773 /* Reject out-of-range values early. Large positive sizes are 2774 used for unknown buffer sizes. */ 2775 if (WARN_ON_ONCE(size > INT_MAX)) 2776 return 0; 2777 2778 str = buf; 2779 end = buf + size; 2780 2781 /* Make sure end is always >= buf */ 2782 if (end < buf) { 2783 end = ((void *)-1); 2784 size = end - buf; 2785 } 2786 2787 while (*fmt.str) { 2788 const char *old_fmt = fmt.str; 2789 2790 fmt = format_decode(fmt, &spec); 2791 2792 switch (fmt.state) { 2793 case FORMAT_STATE_NONE: { 2794 int read = fmt.str - old_fmt; 2795 if (str < end) { 2796 int copy = read; 2797 if (copy > end - str) 2798 copy = end - str; 2799 memcpy(str, old_fmt, copy); 2800 } 2801 str += read; 2802 continue; 2803 } 2804 2805 case FORMAT_STATE_NUM: { 2806 unsigned long long num; 2807 if (fmt.size <= sizeof(int)) 2808 num = convert_num_spec(va_arg(args, int), fmt.size, spec); 2809 else 2810 num = va_arg(args, long long); 2811 str = number(str, end, num, spec); 2812 continue; 2813 } 2814 2815 case FORMAT_STATE_WIDTH: 2816 set_field_width(&spec, va_arg(args, int)); 2817 continue; 2818 2819 case FORMAT_STATE_PRECISION: 2820 set_precision(&spec, va_arg(args, int)); 2821 continue; 2822 2823 case FORMAT_STATE_CHAR: { 2824 char c; 2825 2826 if (!(spec.flags & LEFT)) { 2827 while (--spec.field_width > 0) { 2828 if (str < end) 2829 *str = ' '; 2830 ++str; 2831 2832 } 2833 } 2834 c = (unsigned char) va_arg(args, int); 2835 if (str < end) 2836 *str = c; 2837 ++str; 2838 while (--spec.field_width > 0) { 2839 if (str < end) 2840 *str = ' '; 2841 ++str; 2842 } 2843 continue; 2844 } 2845 2846 case FORMAT_STATE_STR: 2847 str = string(str, end, va_arg(args, char *), spec); 2848 continue; 2849 2850 case FORMAT_STATE_PTR: 2851 str = pointer(fmt.str, str, end, va_arg(args, void *), 2852 spec); 2853 while (isalnum(*fmt.str)) 2854 fmt.str++; 2855 continue; 2856 2857 case FORMAT_STATE_PERCENT_CHAR: 2858 if (str < end) 2859 *str = '%'; 2860 ++str; 2861 continue; 2862 2863 default: 2864 /* 2865 * Presumably the arguments passed gcc's type 2866 * checking, but there is no safe or sane way 2867 * for us to continue parsing the format and 2868 * fetching from the va_list; the remaining 2869 * specifiers and arguments would be out of 2870 * sync. 2871 */ 2872 goto out; 2873 } 2874 } 2875 2876 out: 2877 if (size > 0) { 2878 if (str < end) 2879 *str = '\0'; 2880 else 2881 end[-1] = '\0'; 2882 } 2883 2884 /* the trailing null byte doesn't count towards the total */ 2885 return str-buf; 2886 2887 } 2888 EXPORT_SYMBOL(vsnprintf); 2889 2890 /** 2891 * vscnprintf - Format a string and place it in a buffer 2892 * @buf: The buffer to place the result into 2893 * @size: The size of the buffer, including the trailing null space 2894 * @fmt: The format string to use 2895 * @args: Arguments for the format string 2896 * 2897 * The return value is the number of characters which have been written into 2898 * the @buf not including the trailing '\0'. If @size is == 0 the function 2899 * returns 0. 2900 * 2901 * If you're not already dealing with a va_list consider using scnprintf(). 2902 * 2903 * See the vsnprintf() documentation for format string extensions over C99. 2904 */ 2905 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2906 { 2907 int i; 2908 2909 if (unlikely(!size)) 2910 return 0; 2911 2912 i = vsnprintf(buf, size, fmt, args); 2913 2914 if (likely(i < size)) 2915 return i; 2916 2917 return size - 1; 2918 } 2919 EXPORT_SYMBOL(vscnprintf); 2920 2921 /** 2922 * snprintf - Format a string and place it in a buffer 2923 * @buf: The buffer to place the result into 2924 * @size: The size of the buffer, including the trailing null space 2925 * @fmt: The format string to use 2926 * @...: Arguments for the format string 2927 * 2928 * The return value is the number of characters which would be 2929 * generated for the given input, excluding the trailing null, 2930 * as per ISO C99. If the return is greater than or equal to 2931 * @size, the resulting string is truncated. 2932 * 2933 * See the vsnprintf() documentation for format string extensions over C99. 2934 */ 2935 int snprintf(char *buf, size_t size, const char *fmt, ...) 2936 { 2937 va_list args; 2938 int i; 2939 2940 va_start(args, fmt); 2941 i = vsnprintf(buf, size, fmt, args); 2942 va_end(args); 2943 2944 return i; 2945 } 2946 EXPORT_SYMBOL(snprintf); 2947 2948 /** 2949 * scnprintf - Format a string and place it in a buffer 2950 * @buf: The buffer to place the result into 2951 * @size: The size of the buffer, including the trailing null space 2952 * @fmt: The format string to use 2953 * @...: Arguments for the format string 2954 * 2955 * The return value is the number of characters written into @buf not including 2956 * the trailing '\0'. If @size is == 0 the function returns 0. 2957 */ 2958 2959 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2960 { 2961 va_list args; 2962 int i; 2963 2964 va_start(args, fmt); 2965 i = vscnprintf(buf, size, fmt, args); 2966 va_end(args); 2967 2968 return i; 2969 } 2970 EXPORT_SYMBOL(scnprintf); 2971 2972 /** 2973 * vsprintf - Format a string and place it in a buffer 2974 * @buf: The buffer to place the result into 2975 * @fmt: The format string to use 2976 * @args: Arguments for the format string 2977 * 2978 * The function returns the number of characters written 2979 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2980 * buffer overflows. 2981 * 2982 * If you're not already dealing with a va_list consider using sprintf(). 2983 * 2984 * See the vsnprintf() documentation for format string extensions over C99. 2985 */ 2986 int vsprintf(char *buf, const char *fmt, va_list args) 2987 { 2988 return vsnprintf(buf, INT_MAX, fmt, args); 2989 } 2990 EXPORT_SYMBOL(vsprintf); 2991 2992 /** 2993 * sprintf - Format a string and place it in a buffer 2994 * @buf: The buffer to place the result into 2995 * @fmt: The format string to use 2996 * @...: Arguments for the format string 2997 * 2998 * The function returns the number of characters written 2999 * into @buf. Use snprintf() or scnprintf() in order to avoid 3000 * buffer overflows. 3001 * 3002 * See the vsnprintf() documentation for format string extensions over C99. 3003 */ 3004 int sprintf(char *buf, const char *fmt, ...) 3005 { 3006 va_list args; 3007 int i; 3008 3009 va_start(args, fmt); 3010 i = vsnprintf(buf, INT_MAX, fmt, args); 3011 va_end(args); 3012 3013 return i; 3014 } 3015 EXPORT_SYMBOL(sprintf); 3016 3017 #ifdef CONFIG_BINARY_PRINTF 3018 /* 3019 * bprintf service: 3020 * vbin_printf() - VA arguments to binary data 3021 * bstr_printf() - Binary data to text string 3022 */ 3023 3024 /** 3025 * vbin_printf - Parse a format string and place args' binary value in a buffer 3026 * @bin_buf: The buffer to place args' binary value 3027 * @size: The size of the buffer(by words(32bits), not characters) 3028 * @fmt_str: The format string to use 3029 * @args: Arguments for the format string 3030 * 3031 * The format follows C99 vsnprintf, except %n is ignored, and its argument 3032 * is skipped. 3033 * 3034 * The return value is the number of words(32bits) which would be generated for 3035 * the given input. 3036 * 3037 * NOTE: 3038 * If the return value is greater than @size, the resulting bin_buf is NOT 3039 * valid for bstr_printf(). 3040 */ 3041 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt_str, va_list args) 3042 { 3043 struct fmt fmt = { 3044 .str = fmt_str, 3045 .state = FORMAT_STATE_NONE, 3046 }; 3047 struct printf_spec spec = {0}; 3048 char *str, *end; 3049 int width; 3050 3051 str = (char *)bin_buf; 3052 end = (char *)(bin_buf + size); 3053 3054 #define save_arg(type) \ 3055 ({ \ 3056 unsigned long long value; \ 3057 if (sizeof(type) == 8) { \ 3058 unsigned long long val8; \ 3059 str = PTR_ALIGN(str, sizeof(u32)); \ 3060 val8 = va_arg(args, unsigned long long); \ 3061 if (str + sizeof(type) <= end) { \ 3062 *(u32 *)str = *(u32 *)&val8; \ 3063 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 3064 } \ 3065 value = val8; \ 3066 } else { \ 3067 unsigned int val4; \ 3068 str = PTR_ALIGN(str, sizeof(type)); \ 3069 val4 = va_arg(args, int); \ 3070 if (str + sizeof(type) <= end) \ 3071 *(typeof(type) *)str = (type)(long)val4; \ 3072 value = (unsigned long long)val4; \ 3073 } \ 3074 str += sizeof(type); \ 3075 value; \ 3076 }) 3077 3078 while (*fmt.str) { 3079 fmt = format_decode(fmt, &spec); 3080 3081 switch (fmt.state) { 3082 case FORMAT_STATE_NONE: 3083 case FORMAT_STATE_PERCENT_CHAR: 3084 break; 3085 case FORMAT_STATE_INVALID: 3086 goto out; 3087 3088 case FORMAT_STATE_WIDTH: 3089 case FORMAT_STATE_PRECISION: 3090 width = (int)save_arg(int); 3091 /* Pointers may require the width */ 3092 if (*fmt.str == 'p') 3093 set_field_width(&spec, width); 3094 break; 3095 3096 case FORMAT_STATE_CHAR: 3097 save_arg(char); 3098 break; 3099 3100 case FORMAT_STATE_STR: { 3101 const char *save_str = va_arg(args, char *); 3102 const char *err_msg; 3103 size_t len; 3104 3105 err_msg = check_pointer_msg(save_str); 3106 if (err_msg) 3107 save_str = err_msg; 3108 3109 len = strlen(save_str) + 1; 3110 if (str + len < end) 3111 memcpy(str, save_str, len); 3112 str += len; 3113 break; 3114 } 3115 3116 case FORMAT_STATE_PTR: 3117 /* Dereferenced pointers must be done now */ 3118 switch (*fmt.str) { 3119 /* Dereference of functions is still OK */ 3120 case 'S': 3121 case 's': 3122 case 'x': 3123 case 'K': 3124 case 'e': 3125 save_arg(void *); 3126 break; 3127 default: 3128 if (!isalnum(*fmt.str)) { 3129 save_arg(void *); 3130 break; 3131 } 3132 str = pointer(fmt.str, str, end, va_arg(args, void *), 3133 spec); 3134 if (str + 1 < end) 3135 *str++ = '\0'; 3136 else 3137 end[-1] = '\0'; /* Must be nul terminated */ 3138 } 3139 /* skip all alphanumeric pointer suffixes */ 3140 while (isalnum(*fmt.str)) 3141 fmt.str++; 3142 break; 3143 3144 case FORMAT_STATE_NUM: 3145 if (fmt.size > sizeof(int)) { 3146 save_arg(long long); 3147 } else { 3148 save_arg(int); 3149 } 3150 } 3151 } 3152 3153 out: 3154 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 3155 #undef save_arg 3156 } 3157 EXPORT_SYMBOL_GPL(vbin_printf); 3158 3159 /** 3160 * bstr_printf - Format a string from binary arguments and place it in a buffer 3161 * @buf: The buffer to place the result into 3162 * @size: The size of the buffer, including the trailing null space 3163 * @fmt_str: The format string to use 3164 * @bin_buf: Binary arguments for the format string 3165 * 3166 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 3167 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 3168 * a binary buffer that generated by vbin_printf. 3169 * 3170 * The format follows C99 vsnprintf, but has some extensions: 3171 * see vsnprintf comment for details. 3172 * 3173 * The return value is the number of characters which would 3174 * be generated for the given input, excluding the trailing 3175 * '\0', as per ISO C99. If you want to have the exact 3176 * number of characters written into @buf as return value 3177 * (not including the trailing '\0'), use vscnprintf(). If the 3178 * return is greater than or equal to @size, the resulting 3179 * string is truncated. 3180 */ 3181 int bstr_printf(char *buf, size_t size, const char *fmt_str, const u32 *bin_buf) 3182 { 3183 struct fmt fmt = { 3184 .str = fmt_str, 3185 .state = FORMAT_STATE_NONE, 3186 }; 3187 struct printf_spec spec = {0}; 3188 char *str, *end; 3189 const char *args = (const char *)bin_buf; 3190 3191 if (WARN_ON_ONCE(size > INT_MAX)) 3192 return 0; 3193 3194 str = buf; 3195 end = buf + size; 3196 3197 #define get_arg(type) \ 3198 ({ \ 3199 typeof(type) value; \ 3200 if (sizeof(type) == 8) { \ 3201 args = PTR_ALIGN(args, sizeof(u32)); \ 3202 *(u32 *)&value = *(u32 *)args; \ 3203 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 3204 } else { \ 3205 args = PTR_ALIGN(args, sizeof(type)); \ 3206 value = *(typeof(type) *)args; \ 3207 } \ 3208 args += sizeof(type); \ 3209 value; \ 3210 }) 3211 3212 /* Make sure end is always >= buf */ 3213 if (end < buf) { 3214 end = ((void *)-1); 3215 size = end - buf; 3216 } 3217 3218 while (*fmt.str) { 3219 const char *old_fmt = fmt.str; 3220 unsigned long long num; 3221 3222 fmt = format_decode(fmt, &spec); 3223 switch (fmt.state) { 3224 case FORMAT_STATE_NONE: { 3225 int read = fmt.str - old_fmt; 3226 if (str < end) { 3227 int copy = read; 3228 if (copy > end - str) 3229 copy = end - str; 3230 memcpy(str, old_fmt, copy); 3231 } 3232 str += read; 3233 continue; 3234 } 3235 3236 case FORMAT_STATE_WIDTH: 3237 set_field_width(&spec, get_arg(int)); 3238 continue; 3239 3240 case FORMAT_STATE_PRECISION: 3241 set_precision(&spec, get_arg(int)); 3242 continue; 3243 3244 case FORMAT_STATE_CHAR: { 3245 char c; 3246 3247 if (!(spec.flags & LEFT)) { 3248 while (--spec.field_width > 0) { 3249 if (str < end) 3250 *str = ' '; 3251 ++str; 3252 } 3253 } 3254 c = (unsigned char) get_arg(char); 3255 if (str < end) 3256 *str = c; 3257 ++str; 3258 while (--spec.field_width > 0) { 3259 if (str < end) 3260 *str = ' '; 3261 ++str; 3262 } 3263 continue; 3264 } 3265 3266 case FORMAT_STATE_STR: { 3267 const char *str_arg = args; 3268 args += strlen(str_arg) + 1; 3269 str = string(str, end, (char *)str_arg, spec); 3270 continue; 3271 } 3272 3273 case FORMAT_STATE_PTR: { 3274 bool process = false; 3275 int copy, len; 3276 /* Non function dereferences were already done */ 3277 switch (*fmt.str) { 3278 case 'S': 3279 case 's': 3280 case 'x': 3281 case 'K': 3282 case 'e': 3283 process = true; 3284 break; 3285 default: 3286 if (!isalnum(*fmt.str)) { 3287 process = true; 3288 break; 3289 } 3290 /* Pointer dereference was already processed */ 3291 if (str < end) { 3292 len = copy = strlen(args); 3293 if (copy > end - str) 3294 copy = end - str; 3295 memcpy(str, args, copy); 3296 str += len; 3297 args += len + 1; 3298 } 3299 } 3300 if (process) 3301 str = pointer(fmt.str, str, end, get_arg(void *), spec); 3302 3303 while (isalnum(*fmt.str)) 3304 fmt.str++; 3305 continue; 3306 } 3307 3308 case FORMAT_STATE_PERCENT_CHAR: 3309 if (str < end) 3310 *str = '%'; 3311 ++str; 3312 continue; 3313 3314 case FORMAT_STATE_INVALID: 3315 goto out; 3316 3317 case FORMAT_STATE_NUM: 3318 if (fmt.size > sizeof(int)) { 3319 num = get_arg(long long); 3320 } else { 3321 num = convert_num_spec(get_arg(int), fmt.size, spec); 3322 } 3323 str = number(str, end, num, spec); 3324 continue; 3325 } 3326 } /* while(*fmt.str) */ 3327 3328 out: 3329 if (size > 0) { 3330 if (str < end) 3331 *str = '\0'; 3332 else 3333 end[-1] = '\0'; 3334 } 3335 3336 #undef get_arg 3337 3338 /* the trailing null byte doesn't count towards the total */ 3339 return str - buf; 3340 } 3341 EXPORT_SYMBOL_GPL(bstr_printf); 3342 3343 #endif /* CONFIG_BINARY_PRINTF */ 3344 3345 /** 3346 * vsscanf - Unformat a buffer into a list of arguments 3347 * @buf: input buffer 3348 * @fmt: format of buffer 3349 * @args: arguments 3350 */ 3351 int vsscanf(const char *buf, const char *fmt, va_list args) 3352 { 3353 const char *str = buf; 3354 char *next; 3355 char digit; 3356 int num = 0; 3357 u8 qualifier; 3358 unsigned int base; 3359 union { 3360 long long s; 3361 unsigned long long u; 3362 } val; 3363 s16 field_width; 3364 bool is_sign; 3365 3366 while (*fmt) { 3367 /* skip any white space in format */ 3368 /* white space in format matches any amount of 3369 * white space, including none, in the input. 3370 */ 3371 if (isspace(*fmt)) { 3372 fmt = skip_spaces(++fmt); 3373 str = skip_spaces(str); 3374 } 3375 3376 /* anything that is not a conversion must match exactly */ 3377 if (*fmt != '%' && *fmt) { 3378 if (*fmt++ != *str++) 3379 break; 3380 continue; 3381 } 3382 3383 if (!*fmt) 3384 break; 3385 ++fmt; 3386 3387 /* skip this conversion. 3388 * advance both strings to next white space 3389 */ 3390 if (*fmt == '*') { 3391 if (!*str) 3392 break; 3393 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3394 /* '%*[' not yet supported, invalid format */ 3395 if (*fmt == '[') 3396 return num; 3397 fmt++; 3398 } 3399 while (!isspace(*str) && *str) 3400 str++; 3401 continue; 3402 } 3403 3404 /* get field width */ 3405 field_width = -1; 3406 if (isdigit(*fmt)) { 3407 field_width = skip_atoi(&fmt); 3408 if (field_width <= 0) 3409 break; 3410 } 3411 3412 /* get conversion qualifier */ 3413 qualifier = -1; 3414 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3415 *fmt == 'z') { 3416 qualifier = *fmt++; 3417 if (unlikely(qualifier == *fmt)) { 3418 if (qualifier == 'h') { 3419 qualifier = 'H'; 3420 fmt++; 3421 } else if (qualifier == 'l') { 3422 qualifier = 'L'; 3423 fmt++; 3424 } 3425 } 3426 } 3427 3428 if (!*fmt) 3429 break; 3430 3431 if (*fmt == 'n') { 3432 /* return number of characters read so far */ 3433 *va_arg(args, int *) = str - buf; 3434 ++fmt; 3435 continue; 3436 } 3437 3438 if (!*str) 3439 break; 3440 3441 base = 10; 3442 is_sign = false; 3443 3444 switch (*fmt++) { 3445 case 'c': 3446 { 3447 char *s = (char *)va_arg(args, char*); 3448 if (field_width == -1) 3449 field_width = 1; 3450 do { 3451 *s++ = *str++; 3452 } while (--field_width > 0 && *str); 3453 num++; 3454 } 3455 continue; 3456 case 's': 3457 { 3458 char *s = (char *)va_arg(args, char *); 3459 if (field_width == -1) 3460 field_width = SHRT_MAX; 3461 /* first, skip leading white space in buffer */ 3462 str = skip_spaces(str); 3463 3464 /* now copy until next white space */ 3465 while (*str && !isspace(*str) && field_width--) 3466 *s++ = *str++; 3467 *s = '\0'; 3468 num++; 3469 } 3470 continue; 3471 /* 3472 * Warning: This implementation of the '[' conversion specifier 3473 * deviates from its glibc counterpart in the following ways: 3474 * (1) It does NOT support ranges i.e. '-' is NOT a special 3475 * character 3476 * (2) It cannot match the closing bracket ']' itself 3477 * (3) A field width is required 3478 * (4) '%*[' (discard matching input) is currently not supported 3479 * 3480 * Example usage: 3481 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3482 * buf1, buf2, buf3); 3483 * if (ret < 3) 3484 * // etc.. 3485 */ 3486 case '[': 3487 { 3488 char *s = (char *)va_arg(args, char *); 3489 DECLARE_BITMAP(set, 256) = {0}; 3490 unsigned int len = 0; 3491 bool negate = (*fmt == '^'); 3492 3493 /* field width is required */ 3494 if (field_width == -1) 3495 return num; 3496 3497 if (negate) 3498 ++fmt; 3499 3500 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3501 __set_bit((u8)*fmt, set); 3502 3503 /* no ']' or no character set found */ 3504 if (!*fmt || !len) 3505 return num; 3506 ++fmt; 3507 3508 if (negate) { 3509 bitmap_complement(set, set, 256); 3510 /* exclude null '\0' byte */ 3511 __clear_bit(0, set); 3512 } 3513 3514 /* match must be non-empty */ 3515 if (!test_bit((u8)*str, set)) 3516 return num; 3517 3518 while (test_bit((u8)*str, set) && field_width--) 3519 *s++ = *str++; 3520 *s = '\0'; 3521 ++num; 3522 } 3523 continue; 3524 case 'o': 3525 base = 8; 3526 break; 3527 case 'x': 3528 case 'X': 3529 base = 16; 3530 break; 3531 case 'i': 3532 base = 0; 3533 fallthrough; 3534 case 'd': 3535 is_sign = true; 3536 fallthrough; 3537 case 'u': 3538 break; 3539 case '%': 3540 /* looking for '%' in str */ 3541 if (*str++ != '%') 3542 return num; 3543 continue; 3544 default: 3545 /* invalid format; stop here */ 3546 return num; 3547 } 3548 3549 /* have some sort of integer conversion. 3550 * first, skip white space in buffer. 3551 */ 3552 str = skip_spaces(str); 3553 3554 digit = *str; 3555 if (is_sign && digit == '-') { 3556 if (field_width == 1) 3557 break; 3558 3559 digit = *(str + 1); 3560 } 3561 3562 if (!digit 3563 || (base == 16 && !isxdigit(digit)) 3564 || (base == 10 && !isdigit(digit)) 3565 || (base == 8 && !isodigit(digit)) 3566 || (base == 0 && !isdigit(digit))) 3567 break; 3568 3569 if (is_sign) 3570 val.s = simple_strntoll(str, &next, base, 3571 field_width >= 0 ? field_width : INT_MAX); 3572 else 3573 val.u = simple_strntoull(str, &next, base, 3574 field_width >= 0 ? field_width : INT_MAX); 3575 3576 switch (qualifier) { 3577 case 'H': /* that's 'hh' in format */ 3578 if (is_sign) 3579 *va_arg(args, signed char *) = val.s; 3580 else 3581 *va_arg(args, unsigned char *) = val.u; 3582 break; 3583 case 'h': 3584 if (is_sign) 3585 *va_arg(args, short *) = val.s; 3586 else 3587 *va_arg(args, unsigned short *) = val.u; 3588 break; 3589 case 'l': 3590 if (is_sign) 3591 *va_arg(args, long *) = val.s; 3592 else 3593 *va_arg(args, unsigned long *) = val.u; 3594 break; 3595 case 'L': 3596 if (is_sign) 3597 *va_arg(args, long long *) = val.s; 3598 else 3599 *va_arg(args, unsigned long long *) = val.u; 3600 break; 3601 case 'z': 3602 *va_arg(args, size_t *) = val.u; 3603 break; 3604 default: 3605 if (is_sign) 3606 *va_arg(args, int *) = val.s; 3607 else 3608 *va_arg(args, unsigned int *) = val.u; 3609 break; 3610 } 3611 num++; 3612 3613 if (!next) 3614 break; 3615 str = next; 3616 } 3617 3618 return num; 3619 } 3620 EXPORT_SYMBOL(vsscanf); 3621 3622 /** 3623 * sscanf - Unformat a buffer into a list of arguments 3624 * @buf: input buffer 3625 * @fmt: formatting of buffer 3626 * @...: resulting arguments 3627 */ 3628 int sscanf(const char *buf, const char *fmt, ...) 3629 { 3630 va_list args; 3631 int i; 3632 3633 va_start(args, fmt); 3634 i = vsscanf(buf, fmt, args); 3635 va_end(args); 3636 3637 return i; 3638 } 3639 EXPORT_SYMBOL(sscanf); 3640