1 /* 2 * linux/lib/vsprintf.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 */ 6 7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */ 8 /* 9 * Wirzenius wrote this portably, Torvalds fucked it up :-) 10 */ 11 12 /* 13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com> 14 * - changed to provide snprintf and vsnprintf functions 15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de> 16 * - scnprintf and vscnprintf 17 */ 18 19 #include <stdarg.h> 20 #include <linux/build_bug.h> 21 #include <linux/clk.h> 22 #include <linux/clk-provider.h> 23 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */ 24 #include <linux/types.h> 25 #include <linux/string.h> 26 #include <linux/ctype.h> 27 #include <linux/kernel.h> 28 #include <linux/kallsyms.h> 29 #include <linux/math64.h> 30 #include <linux/uaccess.h> 31 #include <linux/ioport.h> 32 #include <linux/dcache.h> 33 #include <linux/cred.h> 34 #include <linux/rtc.h> 35 #include <linux/uuid.h> 36 #include <linux/of.h> 37 #include <net/addrconf.h> 38 #include <linux/siphash.h> 39 #include <linux/compiler.h> 40 #ifdef CONFIG_BLOCK 41 #include <linux/blkdev.h> 42 #endif 43 44 #include "../mm/internal.h" /* For the trace_print_flags arrays */ 45 46 #include <asm/page.h> /* for PAGE_SIZE */ 47 #include <asm/byteorder.h> /* cpu_to_le16 */ 48 49 #include <linux/string_helpers.h> 50 #include "kstrtox.h" 51 52 /** 53 * simple_strtoull - convert a string to an unsigned long long 54 * @cp: The start of the string 55 * @endp: A pointer to the end of the parsed string will be placed here 56 * @base: The number base to use 57 * 58 * This function is obsolete. Please use kstrtoull instead. 59 */ 60 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 61 { 62 unsigned long long result; 63 unsigned int rv; 64 65 cp = _parse_integer_fixup_radix(cp, &base); 66 rv = _parse_integer(cp, base, &result); 67 /* FIXME */ 68 cp += (rv & ~KSTRTOX_OVERFLOW); 69 70 if (endp) 71 *endp = (char *)cp; 72 73 return result; 74 } 75 EXPORT_SYMBOL(simple_strtoull); 76 77 /** 78 * simple_strtoul - convert a string to an unsigned long 79 * @cp: The start of the string 80 * @endp: A pointer to the end of the parsed string will be placed here 81 * @base: The number base to use 82 * 83 * This function is obsolete. Please use kstrtoul instead. 84 */ 85 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 86 { 87 return simple_strtoull(cp, endp, base); 88 } 89 EXPORT_SYMBOL(simple_strtoul); 90 91 /** 92 * simple_strtol - convert a string to a signed long 93 * @cp: The start of the string 94 * @endp: A pointer to the end of the parsed string will be placed here 95 * @base: The number base to use 96 * 97 * This function is obsolete. Please use kstrtol instead. 98 */ 99 long simple_strtol(const char *cp, char **endp, unsigned int base) 100 { 101 if (*cp == '-') 102 return -simple_strtoul(cp + 1, endp, base); 103 104 return simple_strtoul(cp, endp, base); 105 } 106 EXPORT_SYMBOL(simple_strtol); 107 108 /** 109 * simple_strtoll - convert a string to a signed long long 110 * @cp: The start of the string 111 * @endp: A pointer to the end of the parsed string will be placed here 112 * @base: The number base to use 113 * 114 * This function is obsolete. Please use kstrtoll instead. 115 */ 116 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 117 { 118 if (*cp == '-') 119 return -simple_strtoull(cp + 1, endp, base); 120 121 return simple_strtoull(cp, endp, base); 122 } 123 EXPORT_SYMBOL(simple_strtoll); 124 125 static noinline_for_stack 126 int skip_atoi(const char **s) 127 { 128 int i = 0; 129 130 do { 131 i = i*10 + *((*s)++) - '0'; 132 } while (isdigit(**s)); 133 134 return i; 135 } 136 137 /* 138 * Decimal conversion is by far the most typical, and is used for 139 * /proc and /sys data. This directly impacts e.g. top performance 140 * with many processes running. We optimize it for speed by emitting 141 * two characters at a time, using a 200 byte lookup table. This 142 * roughly halves the number of multiplications compared to computing 143 * the digits one at a time. Implementation strongly inspired by the 144 * previous version, which in turn used ideas described at 145 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission 146 * from the author, Douglas W. Jones). 147 * 148 * It turns out there is precisely one 26 bit fixed-point 149 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 150 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual 151 * range happens to be somewhat larger (x <= 1073741898), but that's 152 * irrelevant for our purpose. 153 * 154 * For dividing a number in the range [10^4, 10^6-1] by 100, we still 155 * need a 32x32->64 bit multiply, so we simply use the same constant. 156 * 157 * For dividing a number in the range [100, 10^4-1] by 100, there are 158 * several options. The simplest is (x * 0x147b) >> 19, which is valid 159 * for all x <= 43698. 160 */ 161 162 static const u16 decpair[100] = { 163 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) 164 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), 165 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), 166 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), 167 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), 168 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), 169 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), 170 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), 171 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), 172 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), 173 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), 174 #undef _ 175 }; 176 177 /* 178 * This will print a single '0' even if r == 0, since we would 179 * immediately jump to out_r where two 0s would be written but only 180 * one of them accounted for in buf. This is needed by ip4_string 181 * below. All other callers pass a non-zero value of r. 182 */ 183 static noinline_for_stack 184 char *put_dec_trunc8(char *buf, unsigned r) 185 { 186 unsigned q; 187 188 /* 1 <= r < 10^8 */ 189 if (r < 100) 190 goto out_r; 191 192 /* 100 <= r < 10^8 */ 193 q = (r * (u64)0x28f5c29) >> 32; 194 *((u16 *)buf) = decpair[r - 100*q]; 195 buf += 2; 196 197 /* 1 <= q < 10^6 */ 198 if (q < 100) 199 goto out_q; 200 201 /* 100 <= q < 10^6 */ 202 r = (q * (u64)0x28f5c29) >> 32; 203 *((u16 *)buf) = decpair[q - 100*r]; 204 buf += 2; 205 206 /* 1 <= r < 10^4 */ 207 if (r < 100) 208 goto out_r; 209 210 /* 100 <= r < 10^4 */ 211 q = (r * 0x147b) >> 19; 212 *((u16 *)buf) = decpair[r - 100*q]; 213 buf += 2; 214 out_q: 215 /* 1 <= q < 100 */ 216 r = q; 217 out_r: 218 /* 1 <= r < 100 */ 219 *((u16 *)buf) = decpair[r]; 220 buf += r < 10 ? 1 : 2; 221 return buf; 222 } 223 224 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 225 static noinline_for_stack 226 char *put_dec_full8(char *buf, unsigned r) 227 { 228 unsigned q; 229 230 /* 0 <= r < 10^8 */ 231 q = (r * (u64)0x28f5c29) >> 32; 232 *((u16 *)buf) = decpair[r - 100*q]; 233 buf += 2; 234 235 /* 0 <= q < 10^6 */ 236 r = (q * (u64)0x28f5c29) >> 32; 237 *((u16 *)buf) = decpair[q - 100*r]; 238 buf += 2; 239 240 /* 0 <= r < 10^4 */ 241 q = (r * 0x147b) >> 19; 242 *((u16 *)buf) = decpair[r - 100*q]; 243 buf += 2; 244 245 /* 0 <= q < 100 */ 246 *((u16 *)buf) = decpair[q]; 247 buf += 2; 248 return buf; 249 } 250 251 static noinline_for_stack 252 char *put_dec(char *buf, unsigned long long n) 253 { 254 if (n >= 100*1000*1000) 255 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 256 /* 1 <= n <= 1.6e11 */ 257 if (n >= 100*1000*1000) 258 buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); 259 /* 1 <= n < 1e8 */ 260 return put_dec_trunc8(buf, n); 261 } 262 263 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 264 265 static void 266 put_dec_full4(char *buf, unsigned r) 267 { 268 unsigned q; 269 270 /* 0 <= r < 10^4 */ 271 q = (r * 0x147b) >> 19; 272 *((u16 *)buf) = decpair[r - 100*q]; 273 buf += 2; 274 /* 0 <= q < 100 */ 275 *((u16 *)buf) = decpair[q]; 276 } 277 278 /* 279 * Call put_dec_full4 on x % 10000, return x / 10000. 280 * The approximation x/10000 == (x * 0x346DC5D7) >> 43 281 * holds for all x < 1,128,869,999. The largest value this 282 * helper will ever be asked to convert is 1,125,520,955. 283 * (second call in the put_dec code, assuming n is all-ones). 284 */ 285 static noinline_for_stack 286 unsigned put_dec_helper4(char *buf, unsigned x) 287 { 288 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; 289 290 put_dec_full4(buf, x - q * 10000); 291 return q; 292 } 293 294 /* Based on code by Douglas W. Jones found at 295 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour> 296 * (with permission from the author). 297 * Performs no 64-bit division and hence should be fast on 32-bit machines. 298 */ 299 static 300 char *put_dec(char *buf, unsigned long long n) 301 { 302 uint32_t d3, d2, d1, q, h; 303 304 if (n < 100*1000*1000) 305 return put_dec_trunc8(buf, n); 306 307 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */ 308 h = (n >> 32); 309 d2 = (h ) & 0xffff; 310 d3 = (h >> 16); /* implicit "& 0xffff" */ 311 312 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 313 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ 314 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); 315 q = put_dec_helper4(buf, q); 316 317 q += 7671 * d3 + 9496 * d2 + 6 * d1; 318 q = put_dec_helper4(buf+4, q); 319 320 q += 4749 * d3 + 42 * d2; 321 q = put_dec_helper4(buf+8, q); 322 323 q += 281 * d3; 324 buf += 12; 325 if (q) 326 buf = put_dec_trunc8(buf, q); 327 else while (buf[-1] == '0') 328 --buf; 329 330 return buf; 331 } 332 333 #endif 334 335 /* 336 * Convert passed number to decimal string. 337 * Returns the length of string. On buffer overflow, returns 0. 338 * 339 * If speed is not important, use snprintf(). It's easy to read the code. 340 */ 341 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) 342 { 343 /* put_dec requires 2-byte alignment of the buffer. */ 344 char tmp[sizeof(num) * 3] __aligned(2); 345 int idx, len; 346 347 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ 348 if (num <= 9) { 349 tmp[0] = '0' + num; 350 len = 1; 351 } else { 352 len = put_dec(tmp, num) - tmp; 353 } 354 355 if (len > size || width > size) 356 return 0; 357 358 if (width > len) { 359 width = width - len; 360 for (idx = 0; idx < width; idx++) 361 buf[idx] = ' '; 362 } else { 363 width = 0; 364 } 365 366 for (idx = 0; idx < len; ++idx) 367 buf[idx + width] = tmp[len - idx - 1]; 368 369 return len + width; 370 } 371 372 #define SIGN 1 /* unsigned/signed, must be 1 */ 373 #define LEFT 2 /* left justified */ 374 #define PLUS 4 /* show plus */ 375 #define SPACE 8 /* space if plus */ 376 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ 377 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 378 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 379 380 enum format_type { 381 FORMAT_TYPE_NONE, /* Just a string part */ 382 FORMAT_TYPE_WIDTH, 383 FORMAT_TYPE_PRECISION, 384 FORMAT_TYPE_CHAR, 385 FORMAT_TYPE_STR, 386 FORMAT_TYPE_PTR, 387 FORMAT_TYPE_PERCENT_CHAR, 388 FORMAT_TYPE_INVALID, 389 FORMAT_TYPE_LONG_LONG, 390 FORMAT_TYPE_ULONG, 391 FORMAT_TYPE_LONG, 392 FORMAT_TYPE_UBYTE, 393 FORMAT_TYPE_BYTE, 394 FORMAT_TYPE_USHORT, 395 FORMAT_TYPE_SHORT, 396 FORMAT_TYPE_UINT, 397 FORMAT_TYPE_INT, 398 FORMAT_TYPE_SIZE_T, 399 FORMAT_TYPE_PTRDIFF 400 }; 401 402 struct printf_spec { 403 unsigned int type:8; /* format_type enum */ 404 signed int field_width:24; /* width of output field */ 405 unsigned int flags:8; /* flags to number() */ 406 unsigned int base:8; /* number base, 8, 10 or 16 only */ 407 signed int precision:16; /* # of digits/chars */ 408 } __packed; 409 static_assert(sizeof(struct printf_spec) == 8); 410 411 #define FIELD_WIDTH_MAX ((1 << 23) - 1) 412 #define PRECISION_MAX ((1 << 15) - 1) 413 414 static noinline_for_stack 415 char *number(char *buf, char *end, unsigned long long num, 416 struct printf_spec spec) 417 { 418 /* put_dec requires 2-byte alignment of the buffer. */ 419 char tmp[3 * sizeof(num)] __aligned(2); 420 char sign; 421 char locase; 422 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 423 int i; 424 bool is_zero = num == 0LL; 425 int field_width = spec.field_width; 426 int precision = spec.precision; 427 428 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 429 * produces same digits or (maybe lowercased) letters */ 430 locase = (spec.flags & SMALL); 431 if (spec.flags & LEFT) 432 spec.flags &= ~ZEROPAD; 433 sign = 0; 434 if (spec.flags & SIGN) { 435 if ((signed long long)num < 0) { 436 sign = '-'; 437 num = -(signed long long)num; 438 field_width--; 439 } else if (spec.flags & PLUS) { 440 sign = '+'; 441 field_width--; 442 } else if (spec.flags & SPACE) { 443 sign = ' '; 444 field_width--; 445 } 446 } 447 if (need_pfx) { 448 if (spec.base == 16) 449 field_width -= 2; 450 else if (!is_zero) 451 field_width--; 452 } 453 454 /* generate full string in tmp[], in reverse order */ 455 i = 0; 456 if (num < spec.base) 457 tmp[i++] = hex_asc_upper[num] | locase; 458 else if (spec.base != 10) { /* 8 or 16 */ 459 int mask = spec.base - 1; 460 int shift = 3; 461 462 if (spec.base == 16) 463 shift = 4; 464 do { 465 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); 466 num >>= shift; 467 } while (num); 468 } else { /* base 10 */ 469 i = put_dec(tmp, num) - tmp; 470 } 471 472 /* printing 100 using %2d gives "100", not "00" */ 473 if (i > precision) 474 precision = i; 475 /* leading space padding */ 476 field_width -= precision; 477 if (!(spec.flags & (ZEROPAD | LEFT))) { 478 while (--field_width >= 0) { 479 if (buf < end) 480 *buf = ' '; 481 ++buf; 482 } 483 } 484 /* sign */ 485 if (sign) { 486 if (buf < end) 487 *buf = sign; 488 ++buf; 489 } 490 /* "0x" / "0" prefix */ 491 if (need_pfx) { 492 if (spec.base == 16 || !is_zero) { 493 if (buf < end) 494 *buf = '0'; 495 ++buf; 496 } 497 if (spec.base == 16) { 498 if (buf < end) 499 *buf = ('X' | locase); 500 ++buf; 501 } 502 } 503 /* zero or space padding */ 504 if (!(spec.flags & LEFT)) { 505 char c = ' ' + (spec.flags & ZEROPAD); 506 BUILD_BUG_ON(' ' + ZEROPAD != '0'); 507 while (--field_width >= 0) { 508 if (buf < end) 509 *buf = c; 510 ++buf; 511 } 512 } 513 /* hmm even more zero padding? */ 514 while (i <= --precision) { 515 if (buf < end) 516 *buf = '0'; 517 ++buf; 518 } 519 /* actual digits of result */ 520 while (--i >= 0) { 521 if (buf < end) 522 *buf = tmp[i]; 523 ++buf; 524 } 525 /* trailing space padding */ 526 while (--field_width >= 0) { 527 if (buf < end) 528 *buf = ' '; 529 ++buf; 530 } 531 532 return buf; 533 } 534 535 static noinline_for_stack 536 char *special_hex_number(char *buf, char *end, unsigned long long num, int size) 537 { 538 struct printf_spec spec; 539 540 spec.type = FORMAT_TYPE_PTR; 541 spec.field_width = 2 + 2 * size; /* 0x + hex */ 542 spec.flags = SPECIAL | SMALL | ZEROPAD; 543 spec.base = 16; 544 spec.precision = -1; 545 546 return number(buf, end, num, spec); 547 } 548 549 static void move_right(char *buf, char *end, unsigned len, unsigned spaces) 550 { 551 size_t size; 552 if (buf >= end) /* nowhere to put anything */ 553 return; 554 size = end - buf; 555 if (size <= spaces) { 556 memset(buf, ' ', size); 557 return; 558 } 559 if (len) { 560 if (len > size - spaces) 561 len = size - spaces; 562 memmove(buf + spaces, buf, len); 563 } 564 memset(buf, ' ', spaces); 565 } 566 567 /* 568 * Handle field width padding for a string. 569 * @buf: current buffer position 570 * @n: length of string 571 * @end: end of output buffer 572 * @spec: for field width and flags 573 * Returns: new buffer position after padding. 574 */ 575 static noinline_for_stack 576 char *widen_string(char *buf, int n, char *end, struct printf_spec spec) 577 { 578 unsigned spaces; 579 580 if (likely(n >= spec.field_width)) 581 return buf; 582 /* we want to pad the sucker */ 583 spaces = spec.field_width - n; 584 if (!(spec.flags & LEFT)) { 585 move_right(buf - n, end, n, spaces); 586 return buf + spaces; 587 } 588 while (spaces--) { 589 if (buf < end) 590 *buf = ' '; 591 ++buf; 592 } 593 return buf; 594 } 595 596 /* Handle string from a well known address. */ 597 static char *string_nocheck(char *buf, char *end, const char *s, 598 struct printf_spec spec) 599 { 600 int len = 0; 601 size_t lim = spec.precision; 602 603 while (lim--) { 604 char c = *s++; 605 if (!c) 606 break; 607 if (buf < end) 608 *buf = c; 609 ++buf; 610 ++len; 611 } 612 return widen_string(buf, len, end, spec); 613 } 614 615 /* Be careful: error messages must fit into the given buffer. */ 616 static char *error_string(char *buf, char *end, const char *s, 617 struct printf_spec spec) 618 { 619 /* 620 * Hard limit to avoid a completely insane messages. It actually 621 * works pretty well because most error messages are in 622 * the many pointer format modifiers. 623 */ 624 if (spec.precision == -1) 625 spec.precision = 2 * sizeof(void *); 626 627 return string_nocheck(buf, end, s, spec); 628 } 629 630 /* 631 * Do not call any complex external code here. Nested printk()/vsprintf() 632 * might cause infinite loops. Failures might break printk() and would 633 * be hard to debug. 634 */ 635 static const char *check_pointer_msg(const void *ptr) 636 { 637 if (!ptr) 638 return "(null)"; 639 640 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) 641 return "(efault)"; 642 643 return NULL; 644 } 645 646 static int check_pointer(char **buf, char *end, const void *ptr, 647 struct printf_spec spec) 648 { 649 const char *err_msg; 650 651 err_msg = check_pointer_msg(ptr); 652 if (err_msg) { 653 *buf = error_string(*buf, end, err_msg, spec); 654 return -EFAULT; 655 } 656 657 return 0; 658 } 659 660 static noinline_for_stack 661 char *string(char *buf, char *end, const char *s, 662 struct printf_spec spec) 663 { 664 if (check_pointer(&buf, end, s, spec)) 665 return buf; 666 667 return string_nocheck(buf, end, s, spec); 668 } 669 670 static char *pointer_string(char *buf, char *end, 671 const void *ptr, 672 struct printf_spec spec) 673 { 674 spec.base = 16; 675 spec.flags |= SMALL; 676 if (spec.field_width == -1) { 677 spec.field_width = 2 * sizeof(ptr); 678 spec.flags |= ZEROPAD; 679 } 680 681 return number(buf, end, (unsigned long int)ptr, spec); 682 } 683 684 /* Make pointers available for printing early in the boot sequence. */ 685 static int debug_boot_weak_hash __ro_after_init; 686 687 static int __init debug_boot_weak_hash_enable(char *str) 688 { 689 debug_boot_weak_hash = 1; 690 pr_info("debug_boot_weak_hash enabled\n"); 691 return 0; 692 } 693 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); 694 695 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key); 696 static siphash_key_t ptr_key __read_mostly; 697 698 static void enable_ptr_key_workfn(struct work_struct *work) 699 { 700 get_random_bytes(&ptr_key, sizeof(ptr_key)); 701 /* Needs to run from preemptible context */ 702 static_branch_disable(¬_filled_random_ptr_key); 703 } 704 705 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); 706 707 static void fill_random_ptr_key(struct random_ready_callback *unused) 708 { 709 /* This may be in an interrupt handler. */ 710 queue_work(system_unbound_wq, &enable_ptr_key_work); 711 } 712 713 static struct random_ready_callback random_ready = { 714 .func = fill_random_ptr_key 715 }; 716 717 static int __init initialize_ptr_random(void) 718 { 719 int key_size = sizeof(ptr_key); 720 int ret; 721 722 /* Use hw RNG if available. */ 723 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) { 724 static_branch_disable(¬_filled_random_ptr_key); 725 return 0; 726 } 727 728 ret = add_random_ready_callback(&random_ready); 729 if (!ret) { 730 return 0; 731 } else if (ret == -EALREADY) { 732 /* This is in preemptible context */ 733 enable_ptr_key_workfn(&enable_ptr_key_work); 734 return 0; 735 } 736 737 return ret; 738 } 739 early_initcall(initialize_ptr_random); 740 741 /* Maps a pointer to a 32 bit unique identifier. */ 742 static char *ptr_to_id(char *buf, char *end, const void *ptr, 743 struct printf_spec spec) 744 { 745 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; 746 unsigned long hashval; 747 748 /* When debugging early boot use non-cryptographically secure hash. */ 749 if (unlikely(debug_boot_weak_hash)) { 750 hashval = hash_long((unsigned long)ptr, 32); 751 return pointer_string(buf, end, (const void *)hashval, spec); 752 } 753 754 if (static_branch_unlikely(¬_filled_random_ptr_key)) { 755 spec.field_width = 2 * sizeof(ptr); 756 /* string length must be less than default_width */ 757 return error_string(buf, end, str, spec); 758 } 759 760 #ifdef CONFIG_64BIT 761 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); 762 /* 763 * Mask off the first 32 bits, this makes explicit that we have 764 * modified the address (and 32 bits is plenty for a unique ID). 765 */ 766 hashval = hashval & 0xffffffff; 767 #else 768 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); 769 #endif 770 return pointer_string(buf, end, (const void *)hashval, spec); 771 } 772 773 int kptr_restrict __read_mostly; 774 775 static noinline_for_stack 776 char *restricted_pointer(char *buf, char *end, const void *ptr, 777 struct printf_spec spec) 778 { 779 switch (kptr_restrict) { 780 case 0: 781 /* Handle as %p, hash and do _not_ leak addresses. */ 782 return ptr_to_id(buf, end, ptr, spec); 783 case 1: { 784 const struct cred *cred; 785 786 /* 787 * kptr_restrict==1 cannot be used in IRQ context 788 * because its test for CAP_SYSLOG would be meaningless. 789 */ 790 if (in_irq() || in_serving_softirq() || in_nmi()) { 791 if (spec.field_width == -1) 792 spec.field_width = 2 * sizeof(ptr); 793 return error_string(buf, end, "pK-error", spec); 794 } 795 796 /* 797 * Only print the real pointer value if the current 798 * process has CAP_SYSLOG and is running with the 799 * same credentials it started with. This is because 800 * access to files is checked at open() time, but %pK 801 * checks permission at read() time. We don't want to 802 * leak pointer values if a binary opens a file using 803 * %pK and then elevates privileges before reading it. 804 */ 805 cred = current_cred(); 806 if (!has_capability_noaudit(current, CAP_SYSLOG) || 807 !uid_eq(cred->euid, cred->uid) || 808 !gid_eq(cred->egid, cred->gid)) 809 ptr = NULL; 810 break; 811 } 812 case 2: 813 default: 814 /* Always print 0's for %pK */ 815 ptr = NULL; 816 break; 817 } 818 819 return pointer_string(buf, end, ptr, spec); 820 } 821 822 static noinline_for_stack 823 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, 824 const char *fmt) 825 { 826 const char *array[4], *s; 827 const struct dentry *p; 828 int depth; 829 int i, n; 830 831 switch (fmt[1]) { 832 case '2': case '3': case '4': 833 depth = fmt[1] - '0'; 834 break; 835 default: 836 depth = 1; 837 } 838 839 rcu_read_lock(); 840 for (i = 0; i < depth; i++, d = p) { 841 if (check_pointer(&buf, end, d, spec)) { 842 rcu_read_unlock(); 843 return buf; 844 } 845 846 p = READ_ONCE(d->d_parent); 847 array[i] = READ_ONCE(d->d_name.name); 848 if (p == d) { 849 if (i) 850 array[i] = ""; 851 i++; 852 break; 853 } 854 } 855 s = array[--i]; 856 for (n = 0; n != spec.precision; n++, buf++) { 857 char c = *s++; 858 if (!c) { 859 if (!i) 860 break; 861 c = '/'; 862 s = array[--i]; 863 } 864 if (buf < end) 865 *buf = c; 866 } 867 rcu_read_unlock(); 868 return widen_string(buf, n, end, spec); 869 } 870 871 #ifdef CONFIG_BLOCK 872 static noinline_for_stack 873 char *bdev_name(char *buf, char *end, struct block_device *bdev, 874 struct printf_spec spec, const char *fmt) 875 { 876 struct gendisk *hd; 877 878 if (check_pointer(&buf, end, bdev, spec)) 879 return buf; 880 881 hd = bdev->bd_disk; 882 buf = string(buf, end, hd->disk_name, spec); 883 if (bdev->bd_part->partno) { 884 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { 885 if (buf < end) 886 *buf = 'p'; 887 buf++; 888 } 889 buf = number(buf, end, bdev->bd_part->partno, spec); 890 } 891 return buf; 892 } 893 #endif 894 895 static noinline_for_stack 896 char *symbol_string(char *buf, char *end, void *ptr, 897 struct printf_spec spec, const char *fmt) 898 { 899 unsigned long value; 900 #ifdef CONFIG_KALLSYMS 901 char sym[KSYM_SYMBOL_LEN]; 902 #endif 903 904 if (fmt[1] == 'R') 905 ptr = __builtin_extract_return_addr(ptr); 906 value = (unsigned long)ptr; 907 908 #ifdef CONFIG_KALLSYMS 909 if (*fmt == 'B') 910 sprint_backtrace(sym, value); 911 else if (*fmt != 'f' && *fmt != 's') 912 sprint_symbol(sym, value); 913 else 914 sprint_symbol_no_offset(sym, value); 915 916 return string_nocheck(buf, end, sym, spec); 917 #else 918 return special_hex_number(buf, end, value, sizeof(void *)); 919 #endif 920 } 921 922 static const struct printf_spec default_str_spec = { 923 .field_width = -1, 924 .precision = -1, 925 }; 926 927 static const struct printf_spec default_flag_spec = { 928 .base = 16, 929 .precision = -1, 930 .flags = SPECIAL | SMALL, 931 }; 932 933 static const struct printf_spec default_dec_spec = { 934 .base = 10, 935 .precision = -1, 936 }; 937 938 static const struct printf_spec default_dec02_spec = { 939 .base = 10, 940 .field_width = 2, 941 .precision = -1, 942 .flags = ZEROPAD, 943 }; 944 945 static const struct printf_spec default_dec04_spec = { 946 .base = 10, 947 .field_width = 4, 948 .precision = -1, 949 .flags = ZEROPAD, 950 }; 951 952 static noinline_for_stack 953 char *resource_string(char *buf, char *end, struct resource *res, 954 struct printf_spec spec, const char *fmt) 955 { 956 #ifndef IO_RSRC_PRINTK_SIZE 957 #define IO_RSRC_PRINTK_SIZE 6 958 #endif 959 960 #ifndef MEM_RSRC_PRINTK_SIZE 961 #define MEM_RSRC_PRINTK_SIZE 10 962 #endif 963 static const struct printf_spec io_spec = { 964 .base = 16, 965 .field_width = IO_RSRC_PRINTK_SIZE, 966 .precision = -1, 967 .flags = SPECIAL | SMALL | ZEROPAD, 968 }; 969 static const struct printf_spec mem_spec = { 970 .base = 16, 971 .field_width = MEM_RSRC_PRINTK_SIZE, 972 .precision = -1, 973 .flags = SPECIAL | SMALL | ZEROPAD, 974 }; 975 static const struct printf_spec bus_spec = { 976 .base = 16, 977 .field_width = 2, 978 .precision = -1, 979 .flags = SMALL | ZEROPAD, 980 }; 981 static const struct printf_spec str_spec = { 982 .field_width = -1, 983 .precision = 10, 984 .flags = LEFT, 985 }; 986 987 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 988 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 989 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 990 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 991 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 992 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 993 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 994 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 995 996 char *p = sym, *pend = sym + sizeof(sym); 997 int decode = (fmt[0] == 'R') ? 1 : 0; 998 const struct printf_spec *specp; 999 1000 if (check_pointer(&buf, end, res, spec)) 1001 return buf; 1002 1003 *p++ = '['; 1004 if (res->flags & IORESOURCE_IO) { 1005 p = string_nocheck(p, pend, "io ", str_spec); 1006 specp = &io_spec; 1007 } else if (res->flags & IORESOURCE_MEM) { 1008 p = string_nocheck(p, pend, "mem ", str_spec); 1009 specp = &mem_spec; 1010 } else if (res->flags & IORESOURCE_IRQ) { 1011 p = string_nocheck(p, pend, "irq ", str_spec); 1012 specp = &default_dec_spec; 1013 } else if (res->flags & IORESOURCE_DMA) { 1014 p = string_nocheck(p, pend, "dma ", str_spec); 1015 specp = &default_dec_spec; 1016 } else if (res->flags & IORESOURCE_BUS) { 1017 p = string_nocheck(p, pend, "bus ", str_spec); 1018 specp = &bus_spec; 1019 } else { 1020 p = string_nocheck(p, pend, "??? ", str_spec); 1021 specp = &mem_spec; 1022 decode = 0; 1023 } 1024 if (decode && res->flags & IORESOURCE_UNSET) { 1025 p = string_nocheck(p, pend, "size ", str_spec); 1026 p = number(p, pend, resource_size(res), *specp); 1027 } else { 1028 p = number(p, pend, res->start, *specp); 1029 if (res->start != res->end) { 1030 *p++ = '-'; 1031 p = number(p, pend, res->end, *specp); 1032 } 1033 } 1034 if (decode) { 1035 if (res->flags & IORESOURCE_MEM_64) 1036 p = string_nocheck(p, pend, " 64bit", str_spec); 1037 if (res->flags & IORESOURCE_PREFETCH) 1038 p = string_nocheck(p, pend, " pref", str_spec); 1039 if (res->flags & IORESOURCE_WINDOW) 1040 p = string_nocheck(p, pend, " window", str_spec); 1041 if (res->flags & IORESOURCE_DISABLED) 1042 p = string_nocheck(p, pend, " disabled", str_spec); 1043 } else { 1044 p = string_nocheck(p, pend, " flags ", str_spec); 1045 p = number(p, pend, res->flags, default_flag_spec); 1046 } 1047 *p++ = ']'; 1048 *p = '\0'; 1049 1050 return string_nocheck(buf, end, sym, spec); 1051 } 1052 1053 static noinline_for_stack 1054 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1055 const char *fmt) 1056 { 1057 int i, len = 1; /* if we pass '%ph[CDN]', field width remains 1058 negative value, fallback to the default */ 1059 char separator; 1060 1061 if (spec.field_width == 0) 1062 /* nothing to print */ 1063 return buf; 1064 1065 if (check_pointer(&buf, end, addr, spec)) 1066 return buf; 1067 1068 switch (fmt[1]) { 1069 case 'C': 1070 separator = ':'; 1071 break; 1072 case 'D': 1073 separator = '-'; 1074 break; 1075 case 'N': 1076 separator = 0; 1077 break; 1078 default: 1079 separator = ' '; 1080 break; 1081 } 1082 1083 if (spec.field_width > 0) 1084 len = min_t(int, spec.field_width, 64); 1085 1086 for (i = 0; i < len; ++i) { 1087 if (buf < end) 1088 *buf = hex_asc_hi(addr[i]); 1089 ++buf; 1090 if (buf < end) 1091 *buf = hex_asc_lo(addr[i]); 1092 ++buf; 1093 1094 if (separator && i != len - 1) { 1095 if (buf < end) 1096 *buf = separator; 1097 ++buf; 1098 } 1099 } 1100 1101 return buf; 1102 } 1103 1104 static noinline_for_stack 1105 char *bitmap_string(char *buf, char *end, unsigned long *bitmap, 1106 struct printf_spec spec, const char *fmt) 1107 { 1108 const int CHUNKSZ = 32; 1109 int nr_bits = max_t(int, spec.field_width, 0); 1110 int i, chunksz; 1111 bool first = true; 1112 1113 if (check_pointer(&buf, end, bitmap, spec)) 1114 return buf; 1115 1116 /* reused to print numbers */ 1117 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; 1118 1119 chunksz = nr_bits & (CHUNKSZ - 1); 1120 if (chunksz == 0) 1121 chunksz = CHUNKSZ; 1122 1123 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; 1124 for (; i >= 0; i -= CHUNKSZ) { 1125 u32 chunkmask, val; 1126 int word, bit; 1127 1128 chunkmask = ((1ULL << chunksz) - 1); 1129 word = i / BITS_PER_LONG; 1130 bit = i % BITS_PER_LONG; 1131 val = (bitmap[word] >> bit) & chunkmask; 1132 1133 if (!first) { 1134 if (buf < end) 1135 *buf = ','; 1136 buf++; 1137 } 1138 first = false; 1139 1140 spec.field_width = DIV_ROUND_UP(chunksz, 4); 1141 buf = number(buf, end, val, spec); 1142 1143 chunksz = CHUNKSZ; 1144 } 1145 return buf; 1146 } 1147 1148 static noinline_for_stack 1149 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap, 1150 struct printf_spec spec, const char *fmt) 1151 { 1152 int nr_bits = max_t(int, spec.field_width, 0); 1153 /* current bit is 'cur', most recently seen range is [rbot, rtop] */ 1154 int cur, rbot, rtop; 1155 bool first = true; 1156 1157 if (check_pointer(&buf, end, bitmap, spec)) 1158 return buf; 1159 1160 rbot = cur = find_first_bit(bitmap, nr_bits); 1161 while (cur < nr_bits) { 1162 rtop = cur; 1163 cur = find_next_bit(bitmap, nr_bits, cur + 1); 1164 if (cur < nr_bits && cur <= rtop + 1) 1165 continue; 1166 1167 if (!first) { 1168 if (buf < end) 1169 *buf = ','; 1170 buf++; 1171 } 1172 first = false; 1173 1174 buf = number(buf, end, rbot, default_dec_spec); 1175 if (rbot < rtop) { 1176 if (buf < end) 1177 *buf = '-'; 1178 buf++; 1179 1180 buf = number(buf, end, rtop, default_dec_spec); 1181 } 1182 1183 rbot = cur; 1184 } 1185 return buf; 1186 } 1187 1188 static noinline_for_stack 1189 char *mac_address_string(char *buf, char *end, u8 *addr, 1190 struct printf_spec spec, const char *fmt) 1191 { 1192 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 1193 char *p = mac_addr; 1194 int i; 1195 char separator; 1196 bool reversed = false; 1197 1198 if (check_pointer(&buf, end, addr, spec)) 1199 return buf; 1200 1201 switch (fmt[1]) { 1202 case 'F': 1203 separator = '-'; 1204 break; 1205 1206 case 'R': 1207 reversed = true; 1208 /* fall through */ 1209 1210 default: 1211 separator = ':'; 1212 break; 1213 } 1214 1215 for (i = 0; i < 6; i++) { 1216 if (reversed) 1217 p = hex_byte_pack(p, addr[5 - i]); 1218 else 1219 p = hex_byte_pack(p, addr[i]); 1220 1221 if (fmt[0] == 'M' && i != 5) 1222 *p++ = separator; 1223 } 1224 *p = '\0'; 1225 1226 return string_nocheck(buf, end, mac_addr, spec); 1227 } 1228 1229 static noinline_for_stack 1230 char *ip4_string(char *p, const u8 *addr, const char *fmt) 1231 { 1232 int i; 1233 bool leading_zeros = (fmt[0] == 'i'); 1234 int index; 1235 int step; 1236 1237 switch (fmt[2]) { 1238 case 'h': 1239 #ifdef __BIG_ENDIAN 1240 index = 0; 1241 step = 1; 1242 #else 1243 index = 3; 1244 step = -1; 1245 #endif 1246 break; 1247 case 'l': 1248 index = 3; 1249 step = -1; 1250 break; 1251 case 'n': 1252 case 'b': 1253 default: 1254 index = 0; 1255 step = 1; 1256 break; 1257 } 1258 for (i = 0; i < 4; i++) { 1259 char temp[4] __aligned(2); /* hold each IP quad in reverse order */ 1260 int digits = put_dec_trunc8(temp, addr[index]) - temp; 1261 if (leading_zeros) { 1262 if (digits < 3) 1263 *p++ = '0'; 1264 if (digits < 2) 1265 *p++ = '0'; 1266 } 1267 /* reverse the digits in the quad */ 1268 while (digits--) 1269 *p++ = temp[digits]; 1270 if (i < 3) 1271 *p++ = '.'; 1272 index += step; 1273 } 1274 *p = '\0'; 1275 1276 return p; 1277 } 1278 1279 static noinline_for_stack 1280 char *ip6_compressed_string(char *p, const char *addr) 1281 { 1282 int i, j, range; 1283 unsigned char zerolength[8]; 1284 int longest = 1; 1285 int colonpos = -1; 1286 u16 word; 1287 u8 hi, lo; 1288 bool needcolon = false; 1289 bool useIPv4; 1290 struct in6_addr in6; 1291 1292 memcpy(&in6, addr, sizeof(struct in6_addr)); 1293 1294 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 1295 1296 memset(zerolength, 0, sizeof(zerolength)); 1297 1298 if (useIPv4) 1299 range = 6; 1300 else 1301 range = 8; 1302 1303 /* find position of longest 0 run */ 1304 for (i = 0; i < range; i++) { 1305 for (j = i; j < range; j++) { 1306 if (in6.s6_addr16[j] != 0) 1307 break; 1308 zerolength[i]++; 1309 } 1310 } 1311 for (i = 0; i < range; i++) { 1312 if (zerolength[i] > longest) { 1313 longest = zerolength[i]; 1314 colonpos = i; 1315 } 1316 } 1317 if (longest == 1) /* don't compress a single 0 */ 1318 colonpos = -1; 1319 1320 /* emit address */ 1321 for (i = 0; i < range; i++) { 1322 if (i == colonpos) { 1323 if (needcolon || i == 0) 1324 *p++ = ':'; 1325 *p++ = ':'; 1326 needcolon = false; 1327 i += longest - 1; 1328 continue; 1329 } 1330 if (needcolon) { 1331 *p++ = ':'; 1332 needcolon = false; 1333 } 1334 /* hex u16 without leading 0s */ 1335 word = ntohs(in6.s6_addr16[i]); 1336 hi = word >> 8; 1337 lo = word & 0xff; 1338 if (hi) { 1339 if (hi > 0x0f) 1340 p = hex_byte_pack(p, hi); 1341 else 1342 *p++ = hex_asc_lo(hi); 1343 p = hex_byte_pack(p, lo); 1344 } 1345 else if (lo > 0x0f) 1346 p = hex_byte_pack(p, lo); 1347 else 1348 *p++ = hex_asc_lo(lo); 1349 needcolon = true; 1350 } 1351 1352 if (useIPv4) { 1353 if (needcolon) 1354 *p++ = ':'; 1355 p = ip4_string(p, &in6.s6_addr[12], "I4"); 1356 } 1357 *p = '\0'; 1358 1359 return p; 1360 } 1361 1362 static noinline_for_stack 1363 char *ip6_string(char *p, const char *addr, const char *fmt) 1364 { 1365 int i; 1366 1367 for (i = 0; i < 8; i++) { 1368 p = hex_byte_pack(p, *addr++); 1369 p = hex_byte_pack(p, *addr++); 1370 if (fmt[0] == 'I' && i != 7) 1371 *p++ = ':'; 1372 } 1373 *p = '\0'; 1374 1375 return p; 1376 } 1377 1378 static noinline_for_stack 1379 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 1380 struct printf_spec spec, const char *fmt) 1381 { 1382 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 1383 1384 if (fmt[0] == 'I' && fmt[2] == 'c') 1385 ip6_compressed_string(ip6_addr, addr); 1386 else 1387 ip6_string(ip6_addr, addr, fmt); 1388 1389 return string_nocheck(buf, end, ip6_addr, spec); 1390 } 1391 1392 static noinline_for_stack 1393 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 1394 struct printf_spec spec, const char *fmt) 1395 { 1396 char ip4_addr[sizeof("255.255.255.255")]; 1397 1398 ip4_string(ip4_addr, addr, fmt); 1399 1400 return string_nocheck(buf, end, ip4_addr, spec); 1401 } 1402 1403 static noinline_for_stack 1404 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, 1405 struct printf_spec spec, const char *fmt) 1406 { 1407 bool have_p = false, have_s = false, have_f = false, have_c = false; 1408 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + 1409 sizeof(":12345") + sizeof("/123456789") + 1410 sizeof("%1234567890")]; 1411 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr); 1412 const u8 *addr = (const u8 *) &sa->sin6_addr; 1413 char fmt6[2] = { fmt[0], '6' }; 1414 u8 off = 0; 1415 1416 fmt++; 1417 while (isalpha(*++fmt)) { 1418 switch (*fmt) { 1419 case 'p': 1420 have_p = true; 1421 break; 1422 case 'f': 1423 have_f = true; 1424 break; 1425 case 's': 1426 have_s = true; 1427 break; 1428 case 'c': 1429 have_c = true; 1430 break; 1431 } 1432 } 1433 1434 if (have_p || have_s || have_f) { 1435 *p = '['; 1436 off = 1; 1437 } 1438 1439 if (fmt6[0] == 'I' && have_c) 1440 p = ip6_compressed_string(ip6_addr + off, addr); 1441 else 1442 p = ip6_string(ip6_addr + off, addr, fmt6); 1443 1444 if (have_p || have_s || have_f) 1445 *p++ = ']'; 1446 1447 if (have_p) { 1448 *p++ = ':'; 1449 p = number(p, pend, ntohs(sa->sin6_port), spec); 1450 } 1451 if (have_f) { 1452 *p++ = '/'; 1453 p = number(p, pend, ntohl(sa->sin6_flowinfo & 1454 IPV6_FLOWINFO_MASK), spec); 1455 } 1456 if (have_s) { 1457 *p++ = '%'; 1458 p = number(p, pend, sa->sin6_scope_id, spec); 1459 } 1460 *p = '\0'; 1461 1462 return string_nocheck(buf, end, ip6_addr, spec); 1463 } 1464 1465 static noinline_for_stack 1466 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, 1467 struct printf_spec spec, const char *fmt) 1468 { 1469 bool have_p = false; 1470 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")]; 1471 char *pend = ip4_addr + sizeof(ip4_addr); 1472 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr; 1473 char fmt4[3] = { fmt[0], '4', 0 }; 1474 1475 fmt++; 1476 while (isalpha(*++fmt)) { 1477 switch (*fmt) { 1478 case 'p': 1479 have_p = true; 1480 break; 1481 case 'h': 1482 case 'l': 1483 case 'n': 1484 case 'b': 1485 fmt4[2] = *fmt; 1486 break; 1487 } 1488 } 1489 1490 p = ip4_string(ip4_addr, addr, fmt4); 1491 if (have_p) { 1492 *p++ = ':'; 1493 p = number(p, pend, ntohs(sa->sin_port), spec); 1494 } 1495 *p = '\0'; 1496 1497 return string_nocheck(buf, end, ip4_addr, spec); 1498 } 1499 1500 static noinline_for_stack 1501 char *ip_addr_string(char *buf, char *end, const void *ptr, 1502 struct printf_spec spec, const char *fmt) 1503 { 1504 char *err_fmt_msg; 1505 1506 if (check_pointer(&buf, end, ptr, spec)) 1507 return buf; 1508 1509 switch (fmt[1]) { 1510 case '6': 1511 return ip6_addr_string(buf, end, ptr, spec, fmt); 1512 case '4': 1513 return ip4_addr_string(buf, end, ptr, spec, fmt); 1514 case 'S': { 1515 const union { 1516 struct sockaddr raw; 1517 struct sockaddr_in v4; 1518 struct sockaddr_in6 v6; 1519 } *sa = ptr; 1520 1521 switch (sa->raw.sa_family) { 1522 case AF_INET: 1523 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); 1524 case AF_INET6: 1525 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); 1526 default: 1527 return error_string(buf, end, "(einval)", spec); 1528 }} 1529 } 1530 1531 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; 1532 return error_string(buf, end, err_fmt_msg, spec); 1533 } 1534 1535 static noinline_for_stack 1536 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, 1537 const char *fmt) 1538 { 1539 bool found = true; 1540 int count = 1; 1541 unsigned int flags = 0; 1542 int len; 1543 1544 if (spec.field_width == 0) 1545 return buf; /* nothing to print */ 1546 1547 if (check_pointer(&buf, end, addr, spec)) 1548 return buf; 1549 1550 do { 1551 switch (fmt[count++]) { 1552 case 'a': 1553 flags |= ESCAPE_ANY; 1554 break; 1555 case 'c': 1556 flags |= ESCAPE_SPECIAL; 1557 break; 1558 case 'h': 1559 flags |= ESCAPE_HEX; 1560 break; 1561 case 'n': 1562 flags |= ESCAPE_NULL; 1563 break; 1564 case 'o': 1565 flags |= ESCAPE_OCTAL; 1566 break; 1567 case 'p': 1568 flags |= ESCAPE_NP; 1569 break; 1570 case 's': 1571 flags |= ESCAPE_SPACE; 1572 break; 1573 default: 1574 found = false; 1575 break; 1576 } 1577 } while (found); 1578 1579 if (!flags) 1580 flags = ESCAPE_ANY_NP; 1581 1582 len = spec.field_width < 0 ? 1 : spec.field_width; 1583 1584 /* 1585 * string_escape_mem() writes as many characters as it can to 1586 * the given buffer, and returns the total size of the output 1587 * had the buffer been big enough. 1588 */ 1589 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); 1590 1591 return buf; 1592 } 1593 1594 static char *va_format(char *buf, char *end, struct va_format *va_fmt, 1595 struct printf_spec spec, const char *fmt) 1596 { 1597 va_list va; 1598 1599 if (check_pointer(&buf, end, va_fmt, spec)) 1600 return buf; 1601 1602 va_copy(va, *va_fmt->va); 1603 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); 1604 va_end(va); 1605 1606 return buf; 1607 } 1608 1609 static noinline_for_stack 1610 char *uuid_string(char *buf, char *end, const u8 *addr, 1611 struct printf_spec spec, const char *fmt) 1612 { 1613 char uuid[UUID_STRING_LEN + 1]; 1614 char *p = uuid; 1615 int i; 1616 const u8 *index = uuid_index; 1617 bool uc = false; 1618 1619 if (check_pointer(&buf, end, addr, spec)) 1620 return buf; 1621 1622 switch (*(++fmt)) { 1623 case 'L': 1624 uc = true; /* fall-through */ 1625 case 'l': 1626 index = guid_index; 1627 break; 1628 case 'B': 1629 uc = true; 1630 break; 1631 } 1632 1633 for (i = 0; i < 16; i++) { 1634 if (uc) 1635 p = hex_byte_pack_upper(p, addr[index[i]]); 1636 else 1637 p = hex_byte_pack(p, addr[index[i]]); 1638 switch (i) { 1639 case 3: 1640 case 5: 1641 case 7: 1642 case 9: 1643 *p++ = '-'; 1644 break; 1645 } 1646 } 1647 1648 *p = 0; 1649 1650 return string_nocheck(buf, end, uuid, spec); 1651 } 1652 1653 static noinline_for_stack 1654 char *netdev_bits(char *buf, char *end, const void *addr, 1655 struct printf_spec spec, const char *fmt) 1656 { 1657 unsigned long long num; 1658 int size; 1659 1660 if (check_pointer(&buf, end, addr, spec)) 1661 return buf; 1662 1663 switch (fmt[1]) { 1664 case 'F': 1665 num = *(const netdev_features_t *)addr; 1666 size = sizeof(netdev_features_t); 1667 break; 1668 default: 1669 return error_string(buf, end, "(%pN?)", spec); 1670 } 1671 1672 return special_hex_number(buf, end, num, size); 1673 } 1674 1675 static noinline_for_stack 1676 char *address_val(char *buf, char *end, const void *addr, 1677 struct printf_spec spec, const char *fmt) 1678 { 1679 unsigned long long num; 1680 int size; 1681 1682 if (check_pointer(&buf, end, addr, spec)) 1683 return buf; 1684 1685 switch (fmt[1]) { 1686 case 'd': 1687 num = *(const dma_addr_t *)addr; 1688 size = sizeof(dma_addr_t); 1689 break; 1690 case 'p': 1691 default: 1692 num = *(const phys_addr_t *)addr; 1693 size = sizeof(phys_addr_t); 1694 break; 1695 } 1696 1697 return special_hex_number(buf, end, num, size); 1698 } 1699 1700 static noinline_for_stack 1701 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1702 { 1703 int year = tm->tm_year + (r ? 0 : 1900); 1704 int mon = tm->tm_mon + (r ? 0 : 1); 1705 1706 buf = number(buf, end, year, default_dec04_spec); 1707 if (buf < end) 1708 *buf = '-'; 1709 buf++; 1710 1711 buf = number(buf, end, mon, default_dec02_spec); 1712 if (buf < end) 1713 *buf = '-'; 1714 buf++; 1715 1716 return number(buf, end, tm->tm_mday, default_dec02_spec); 1717 } 1718 1719 static noinline_for_stack 1720 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) 1721 { 1722 buf = number(buf, end, tm->tm_hour, default_dec02_spec); 1723 if (buf < end) 1724 *buf = ':'; 1725 buf++; 1726 1727 buf = number(buf, end, tm->tm_min, default_dec02_spec); 1728 if (buf < end) 1729 *buf = ':'; 1730 buf++; 1731 1732 return number(buf, end, tm->tm_sec, default_dec02_spec); 1733 } 1734 1735 static noinline_for_stack 1736 char *rtc_str(char *buf, char *end, const struct rtc_time *tm, 1737 struct printf_spec spec, const char *fmt) 1738 { 1739 bool have_t = true, have_d = true; 1740 bool raw = false; 1741 int count = 2; 1742 1743 if (check_pointer(&buf, end, tm, spec)) 1744 return buf; 1745 1746 switch (fmt[count]) { 1747 case 'd': 1748 have_t = false; 1749 count++; 1750 break; 1751 case 't': 1752 have_d = false; 1753 count++; 1754 break; 1755 } 1756 1757 raw = fmt[count] == 'r'; 1758 1759 if (have_d) 1760 buf = date_str(buf, end, tm, raw); 1761 if (have_d && have_t) { 1762 /* Respect ISO 8601 */ 1763 if (buf < end) 1764 *buf = 'T'; 1765 buf++; 1766 } 1767 if (have_t) 1768 buf = time_str(buf, end, tm, raw); 1769 1770 return buf; 1771 } 1772 1773 static noinline_for_stack 1774 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, 1775 const char *fmt) 1776 { 1777 switch (fmt[1]) { 1778 case 'R': 1779 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); 1780 default: 1781 return error_string(buf, end, "(%ptR?)", spec); 1782 } 1783 } 1784 1785 static noinline_for_stack 1786 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, 1787 const char *fmt) 1788 { 1789 if (!IS_ENABLED(CONFIG_HAVE_CLK)) 1790 return error_string(buf, end, "(%pC?)", spec); 1791 1792 if (check_pointer(&buf, end, clk, spec)) 1793 return buf; 1794 1795 switch (fmt[1]) { 1796 case 'n': 1797 default: 1798 #ifdef CONFIG_COMMON_CLK 1799 return string(buf, end, __clk_get_name(clk), spec); 1800 #else 1801 return error_string(buf, end, "(%pC?)", spec); 1802 #endif 1803 } 1804 } 1805 1806 static 1807 char *format_flags(char *buf, char *end, unsigned long flags, 1808 const struct trace_print_flags *names) 1809 { 1810 unsigned long mask; 1811 1812 for ( ; flags && names->name; names++) { 1813 mask = names->mask; 1814 if ((flags & mask) != mask) 1815 continue; 1816 1817 buf = string(buf, end, names->name, default_str_spec); 1818 1819 flags &= ~mask; 1820 if (flags) { 1821 if (buf < end) 1822 *buf = '|'; 1823 buf++; 1824 } 1825 } 1826 1827 if (flags) 1828 buf = number(buf, end, flags, default_flag_spec); 1829 1830 return buf; 1831 } 1832 1833 static noinline_for_stack 1834 char *flags_string(char *buf, char *end, void *flags_ptr, 1835 struct printf_spec spec, const char *fmt) 1836 { 1837 unsigned long flags; 1838 const struct trace_print_flags *names; 1839 1840 if (check_pointer(&buf, end, flags_ptr, spec)) 1841 return buf; 1842 1843 switch (fmt[1]) { 1844 case 'p': 1845 flags = *(unsigned long *)flags_ptr; 1846 /* Remove zone id */ 1847 flags &= (1UL << NR_PAGEFLAGS) - 1; 1848 names = pageflag_names; 1849 break; 1850 case 'v': 1851 flags = *(unsigned long *)flags_ptr; 1852 names = vmaflag_names; 1853 break; 1854 case 'g': 1855 flags = *(gfp_t *)flags_ptr; 1856 names = gfpflag_names; 1857 break; 1858 default: 1859 return error_string(buf, end, "(%pG?)", spec); 1860 } 1861 1862 return format_flags(buf, end, flags, names); 1863 } 1864 1865 static const char *device_node_name_for_depth(const struct device_node *np, int depth) 1866 { 1867 for ( ; np && depth; depth--) 1868 np = np->parent; 1869 1870 return kbasename(np->full_name); 1871 } 1872 1873 static noinline_for_stack 1874 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end) 1875 { 1876 int depth; 1877 const struct device_node *parent = np->parent; 1878 1879 /* special case for root node */ 1880 if (!parent) 1881 return string_nocheck(buf, end, "/", default_str_spec); 1882 1883 for (depth = 0; parent->parent; depth++) 1884 parent = parent->parent; 1885 1886 for ( ; depth >= 0; depth--) { 1887 buf = string_nocheck(buf, end, "/", default_str_spec); 1888 buf = string(buf, end, device_node_name_for_depth(np, depth), 1889 default_str_spec); 1890 } 1891 return buf; 1892 } 1893 1894 static noinline_for_stack 1895 char *device_node_string(char *buf, char *end, struct device_node *dn, 1896 struct printf_spec spec, const char *fmt) 1897 { 1898 char tbuf[sizeof("xxxx") + 1]; 1899 const char *p; 1900 int ret; 1901 char *buf_start = buf; 1902 struct property *prop; 1903 bool has_mult, pass; 1904 static const struct printf_spec num_spec = { 1905 .flags = SMALL, 1906 .field_width = -1, 1907 .precision = -1, 1908 .base = 10, 1909 }; 1910 1911 struct printf_spec str_spec = spec; 1912 str_spec.field_width = -1; 1913 1914 if (!IS_ENABLED(CONFIG_OF)) 1915 return error_string(buf, end, "(%pOF?)", spec); 1916 1917 if (check_pointer(&buf, end, dn, spec)) 1918 return buf; 1919 1920 /* simple case without anything any more format specifiers */ 1921 fmt++; 1922 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) 1923 fmt = "f"; 1924 1925 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { 1926 int precision; 1927 if (pass) { 1928 if (buf < end) 1929 *buf = ':'; 1930 buf++; 1931 } 1932 1933 switch (*fmt) { 1934 case 'f': /* full_name */ 1935 buf = device_node_gen_full_name(dn, buf, end); 1936 break; 1937 case 'n': /* name */ 1938 p = kbasename(of_node_full_name(dn)); 1939 precision = str_spec.precision; 1940 str_spec.precision = strchrnul(p, '@') - p; 1941 buf = string(buf, end, p, str_spec); 1942 str_spec.precision = precision; 1943 break; 1944 case 'p': /* phandle */ 1945 buf = number(buf, end, (unsigned int)dn->phandle, num_spec); 1946 break; 1947 case 'P': /* path-spec */ 1948 p = kbasename(of_node_full_name(dn)); 1949 if (!p[1]) 1950 p = "/"; 1951 buf = string(buf, end, p, str_spec); 1952 break; 1953 case 'F': /* flags */ 1954 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; 1955 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; 1956 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; 1957 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; 1958 tbuf[4] = 0; 1959 buf = string_nocheck(buf, end, tbuf, str_spec); 1960 break; 1961 case 'c': /* major compatible string */ 1962 ret = of_property_read_string(dn, "compatible", &p); 1963 if (!ret) 1964 buf = string(buf, end, p, str_spec); 1965 break; 1966 case 'C': /* full compatible string */ 1967 has_mult = false; 1968 of_property_for_each_string(dn, "compatible", prop, p) { 1969 if (has_mult) 1970 buf = string_nocheck(buf, end, ",", str_spec); 1971 buf = string_nocheck(buf, end, "\"", str_spec); 1972 buf = string(buf, end, p, str_spec); 1973 buf = string_nocheck(buf, end, "\"", str_spec); 1974 1975 has_mult = true; 1976 } 1977 break; 1978 default: 1979 break; 1980 } 1981 } 1982 1983 return widen_string(buf, buf - buf_start, end, spec); 1984 } 1985 1986 static char *kobject_string(char *buf, char *end, void *ptr, 1987 struct printf_spec spec, const char *fmt) 1988 { 1989 switch (fmt[1]) { 1990 case 'F': 1991 return device_node_string(buf, end, ptr, spec, fmt + 1); 1992 } 1993 1994 return error_string(buf, end, "(%pO?)", spec); 1995 } 1996 1997 /* 1998 * Show a '%p' thing. A kernel extension is that the '%p' is followed 1999 * by an extra set of alphanumeric characters that are extended format 2000 * specifiers. 2001 * 2002 * Please update scripts/checkpatch.pl when adding/removing conversion 2003 * characters. (Search for "check for vsprintf extension"). 2004 * 2005 * Right now we handle: 2006 * 2007 * - 'S' For symbolic direct pointers (or function descriptors) with offset 2008 * - 's' For symbolic direct pointers (or function descriptors) without offset 2009 * - 'F' Same as 'S' 2010 * - 'f' Same as 's' 2011 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation 2012 * - 'B' For backtraced symbolic direct pointers with offset 2013 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 2014 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 2015 * - 'b[l]' For a bitmap, the number of bits is determined by the field 2016 * width which must be explicitly specified either as part of the 2017 * format string '%32b[l]' or through '%*b[l]', [l] selects 2018 * range-list format instead of hex format 2019 * - 'M' For a 6-byte MAC address, it prints the address in the 2020 * usual colon-separated hex notation 2021 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 2022 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 2023 * with a dash-separated hex notation 2024 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth) 2025 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 2026 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 2027 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 2028 * [S][pfs] 2029 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2030 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2031 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 2032 * IPv6 omits the colons (01020304...0f) 2033 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 2034 * [S][pfs] 2035 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to 2036 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] 2037 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order 2038 * - 'I[6S]c' for IPv6 addresses printed as specified by 2039 * http://tools.ietf.org/html/rfc5952 2040 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination 2041 * of the following flags (see string_escape_mem() for the 2042 * details): 2043 * a - ESCAPE_ANY 2044 * c - ESCAPE_SPECIAL 2045 * h - ESCAPE_HEX 2046 * n - ESCAPE_NULL 2047 * o - ESCAPE_OCTAL 2048 * p - ESCAPE_NP 2049 * s - ESCAPE_SPACE 2050 * By default ESCAPE_ANY_NP is used. 2051 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 2052 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 2053 * Options for %pU are: 2054 * b big endian lower case hex (default) 2055 * B big endian UPPER case hex 2056 * l little endian lower case hex 2057 * L little endian UPPER case hex 2058 * big endian output byte order is: 2059 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 2060 * little endian output byte order is: 2061 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 2062 * - 'V' For a struct va_format which contains a format string * and va_list *, 2063 * call vsnprintf(->format, *->va_list). 2064 * Implements a "recursive vsnprintf". 2065 * Do not use this feature without some mechanism to verify the 2066 * correctness of the format string and va_list arguments. 2067 * - 'K' For a kernel pointer that should be hidden from unprivileged users 2068 * - 'NF' For a netdev_features_t 2069 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with 2070 * a certain separator (' ' by default): 2071 * C colon 2072 * D dash 2073 * N no separator 2074 * The maximum supported length is 64 bytes of the input. Consider 2075 * to use print_hex_dump() for the larger input. 2076 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives 2077 * (default assumed to be phys_addr_t, passed by reference) 2078 * - 'd[234]' For a dentry name (optionally 2-4 last components) 2079 * - 'D[234]' Same as 'd' but for a struct file 2080 * - 'g' For block_device name (gendisk + partition number) 2081 * - 't[R][dt][r]' For time and date as represented: 2082 * R struct rtc_time 2083 * - 'C' For a clock, it prints the name (Common Clock Framework) or address 2084 * (legacy clock framework) of the clock 2085 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address 2086 * (legacy clock framework) of the clock 2087 * - 'G' For flags to be printed as a collection of symbolic strings that would 2088 * construct the specific value. Supported flags given by option: 2089 * p page flags (see struct page) given as pointer to unsigned long 2090 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t 2091 * v vma flags (VM_*) given as pointer to unsigned long 2092 * - 'OF[fnpPcCF]' For a device tree object 2093 * Without any optional arguments prints the full_name 2094 * f device node full_name 2095 * n device node name 2096 * p device node phandle 2097 * P device node path spec (name + @unit) 2098 * F device node flags 2099 * c major compatible string 2100 * C full compatible string 2101 * - 'x' For printing the address. Equivalent to "%lx". 2102 * 2103 * ** When making changes please also update: 2104 * Documentation/core-api/printk-formats.rst 2105 * 2106 * Note: The default behaviour (unadorned %p) is to hash the address, 2107 * rendering it useful as a unique identifier. 2108 */ 2109 static noinline_for_stack 2110 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 2111 struct printf_spec spec) 2112 { 2113 switch (*fmt) { 2114 case 'F': 2115 case 'f': 2116 case 'S': 2117 case 's': 2118 ptr = dereference_symbol_descriptor(ptr); 2119 /* Fallthrough */ 2120 case 'B': 2121 return symbol_string(buf, end, ptr, spec, fmt); 2122 case 'R': 2123 case 'r': 2124 return resource_string(buf, end, ptr, spec, fmt); 2125 case 'h': 2126 return hex_string(buf, end, ptr, spec, fmt); 2127 case 'b': 2128 switch (fmt[1]) { 2129 case 'l': 2130 return bitmap_list_string(buf, end, ptr, spec, fmt); 2131 default: 2132 return bitmap_string(buf, end, ptr, spec, fmt); 2133 } 2134 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 2135 case 'm': /* Contiguous: 000102030405 */ 2136 /* [mM]F (FDDI) */ 2137 /* [mM]R (Reverse order; Bluetooth) */ 2138 return mac_address_string(buf, end, ptr, spec, fmt); 2139 case 'I': /* Formatted IP supported 2140 * 4: 1.2.3.4 2141 * 6: 0001:0203:...:0708 2142 * 6c: 1::708 or 1::1.2.3.4 2143 */ 2144 case 'i': /* Contiguous: 2145 * 4: 001.002.003.004 2146 * 6: 000102...0f 2147 */ 2148 return ip_addr_string(buf, end, ptr, spec, fmt); 2149 case 'E': 2150 return escaped_string(buf, end, ptr, spec, fmt); 2151 case 'U': 2152 return uuid_string(buf, end, ptr, spec, fmt); 2153 case 'V': 2154 return va_format(buf, end, ptr, spec, fmt); 2155 case 'K': 2156 return restricted_pointer(buf, end, ptr, spec); 2157 case 'N': 2158 return netdev_bits(buf, end, ptr, spec, fmt); 2159 case 'a': 2160 return address_val(buf, end, ptr, spec, fmt); 2161 case 'd': 2162 return dentry_name(buf, end, ptr, spec, fmt); 2163 case 't': 2164 return time_and_date(buf, end, ptr, spec, fmt); 2165 case 'C': 2166 return clock(buf, end, ptr, spec, fmt); 2167 case 'D': 2168 return dentry_name(buf, end, 2169 ((const struct file *)ptr)->f_path.dentry, 2170 spec, fmt); 2171 #ifdef CONFIG_BLOCK 2172 case 'g': 2173 return bdev_name(buf, end, ptr, spec, fmt); 2174 #endif 2175 2176 case 'G': 2177 return flags_string(buf, end, ptr, spec, fmt); 2178 case 'O': 2179 return kobject_string(buf, end, ptr, spec, fmt); 2180 case 'x': 2181 return pointer_string(buf, end, ptr, spec); 2182 } 2183 2184 /* default is to _not_ leak addresses, hash before printing */ 2185 return ptr_to_id(buf, end, ptr, spec); 2186 } 2187 2188 /* 2189 * Helper function to decode printf style format. 2190 * Each call decode a token from the format and return the 2191 * number of characters read (or likely the delta where it wants 2192 * to go on the next call). 2193 * The decoded token is returned through the parameters 2194 * 2195 * 'h', 'l', or 'L' for integer fields 2196 * 'z' support added 23/7/1999 S.H. 2197 * 'z' changed to 'Z' --davidm 1/25/99 2198 * 'Z' changed to 'z' --adobriyan 2017-01-25 2199 * 't' added for ptrdiff_t 2200 * 2201 * @fmt: the format string 2202 * @type of the token returned 2203 * @flags: various flags such as +, -, # tokens.. 2204 * @field_width: overwritten width 2205 * @base: base of the number (octal, hex, ...) 2206 * @precision: precision of a number 2207 * @qualifier: qualifier of a number (long, size_t, ...) 2208 */ 2209 static noinline_for_stack 2210 int format_decode(const char *fmt, struct printf_spec *spec) 2211 { 2212 const char *start = fmt; 2213 char qualifier; 2214 2215 /* we finished early by reading the field width */ 2216 if (spec->type == FORMAT_TYPE_WIDTH) { 2217 if (spec->field_width < 0) { 2218 spec->field_width = -spec->field_width; 2219 spec->flags |= LEFT; 2220 } 2221 spec->type = FORMAT_TYPE_NONE; 2222 goto precision; 2223 } 2224 2225 /* we finished early by reading the precision */ 2226 if (spec->type == FORMAT_TYPE_PRECISION) { 2227 if (spec->precision < 0) 2228 spec->precision = 0; 2229 2230 spec->type = FORMAT_TYPE_NONE; 2231 goto qualifier; 2232 } 2233 2234 /* By default */ 2235 spec->type = FORMAT_TYPE_NONE; 2236 2237 for (; *fmt ; ++fmt) { 2238 if (*fmt == '%') 2239 break; 2240 } 2241 2242 /* Return the current non-format string */ 2243 if (fmt != start || !*fmt) 2244 return fmt - start; 2245 2246 /* Process flags */ 2247 spec->flags = 0; 2248 2249 while (1) { /* this also skips first '%' */ 2250 bool found = true; 2251 2252 ++fmt; 2253 2254 switch (*fmt) { 2255 case '-': spec->flags |= LEFT; break; 2256 case '+': spec->flags |= PLUS; break; 2257 case ' ': spec->flags |= SPACE; break; 2258 case '#': spec->flags |= SPECIAL; break; 2259 case '0': spec->flags |= ZEROPAD; break; 2260 default: found = false; 2261 } 2262 2263 if (!found) 2264 break; 2265 } 2266 2267 /* get field width */ 2268 spec->field_width = -1; 2269 2270 if (isdigit(*fmt)) 2271 spec->field_width = skip_atoi(&fmt); 2272 else if (*fmt == '*') { 2273 /* it's the next argument */ 2274 spec->type = FORMAT_TYPE_WIDTH; 2275 return ++fmt - start; 2276 } 2277 2278 precision: 2279 /* get the precision */ 2280 spec->precision = -1; 2281 if (*fmt == '.') { 2282 ++fmt; 2283 if (isdigit(*fmt)) { 2284 spec->precision = skip_atoi(&fmt); 2285 if (spec->precision < 0) 2286 spec->precision = 0; 2287 } else if (*fmt == '*') { 2288 /* it's the next argument */ 2289 spec->type = FORMAT_TYPE_PRECISION; 2290 return ++fmt - start; 2291 } 2292 } 2293 2294 qualifier: 2295 /* get the conversion qualifier */ 2296 qualifier = 0; 2297 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 2298 *fmt == 'z' || *fmt == 't') { 2299 qualifier = *fmt++; 2300 if (unlikely(qualifier == *fmt)) { 2301 if (qualifier == 'l') { 2302 qualifier = 'L'; 2303 ++fmt; 2304 } else if (qualifier == 'h') { 2305 qualifier = 'H'; 2306 ++fmt; 2307 } 2308 } 2309 } 2310 2311 /* default base */ 2312 spec->base = 10; 2313 switch (*fmt) { 2314 case 'c': 2315 spec->type = FORMAT_TYPE_CHAR; 2316 return ++fmt - start; 2317 2318 case 's': 2319 spec->type = FORMAT_TYPE_STR; 2320 return ++fmt - start; 2321 2322 case 'p': 2323 spec->type = FORMAT_TYPE_PTR; 2324 return ++fmt - start; 2325 2326 case '%': 2327 spec->type = FORMAT_TYPE_PERCENT_CHAR; 2328 return ++fmt - start; 2329 2330 /* integer number formats - set up the flags and "break" */ 2331 case 'o': 2332 spec->base = 8; 2333 break; 2334 2335 case 'x': 2336 spec->flags |= SMALL; 2337 /* fall through */ 2338 2339 case 'X': 2340 spec->base = 16; 2341 break; 2342 2343 case 'd': 2344 case 'i': 2345 spec->flags |= SIGN; 2346 case 'u': 2347 break; 2348 2349 case 'n': 2350 /* 2351 * Since %n poses a greater security risk than 2352 * utility, treat it as any other invalid or 2353 * unsupported format specifier. 2354 */ 2355 /* Fall-through */ 2356 2357 default: 2358 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt); 2359 spec->type = FORMAT_TYPE_INVALID; 2360 return fmt - start; 2361 } 2362 2363 if (qualifier == 'L') 2364 spec->type = FORMAT_TYPE_LONG_LONG; 2365 else if (qualifier == 'l') { 2366 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG); 2367 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN); 2368 } else if (qualifier == 'z') { 2369 spec->type = FORMAT_TYPE_SIZE_T; 2370 } else if (qualifier == 't') { 2371 spec->type = FORMAT_TYPE_PTRDIFF; 2372 } else if (qualifier == 'H') { 2373 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE); 2374 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN); 2375 } else if (qualifier == 'h') { 2376 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT); 2377 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN); 2378 } else { 2379 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT); 2380 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN); 2381 } 2382 2383 return ++fmt - start; 2384 } 2385 2386 static void 2387 set_field_width(struct printf_spec *spec, int width) 2388 { 2389 spec->field_width = width; 2390 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { 2391 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); 2392 } 2393 } 2394 2395 static void 2396 set_precision(struct printf_spec *spec, int prec) 2397 { 2398 spec->precision = prec; 2399 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { 2400 spec->precision = clamp(prec, 0, PRECISION_MAX); 2401 } 2402 } 2403 2404 /** 2405 * vsnprintf - Format a string and place it in a buffer 2406 * @buf: The buffer to place the result into 2407 * @size: The size of the buffer, including the trailing null space 2408 * @fmt: The format string to use 2409 * @args: Arguments for the format string 2410 * 2411 * This function generally follows C99 vsnprintf, but has some 2412 * extensions and a few limitations: 2413 * 2414 * - ``%n`` is unsupported 2415 * - ``%p*`` is handled by pointer() 2416 * 2417 * See pointer() or Documentation/core-api/printk-formats.rst for more 2418 * extensive description. 2419 * 2420 * **Please update the documentation in both places when making changes** 2421 * 2422 * The return value is the number of characters which would 2423 * be generated for the given input, excluding the trailing 2424 * '\0', as per ISO C99. If you want to have the exact 2425 * number of characters written into @buf as return value 2426 * (not including the trailing '\0'), use vscnprintf(). If the 2427 * return is greater than or equal to @size, the resulting 2428 * string is truncated. 2429 * 2430 * If you're not already dealing with a va_list consider using snprintf(). 2431 */ 2432 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 2433 { 2434 unsigned long long num; 2435 char *str, *end; 2436 struct printf_spec spec = {0}; 2437 2438 /* Reject out-of-range values early. Large positive sizes are 2439 used for unknown buffer sizes. */ 2440 if (WARN_ON_ONCE(size > INT_MAX)) 2441 return 0; 2442 2443 str = buf; 2444 end = buf + size; 2445 2446 /* Make sure end is always >= buf */ 2447 if (end < buf) { 2448 end = ((void *)-1); 2449 size = end - buf; 2450 } 2451 2452 while (*fmt) { 2453 const char *old_fmt = fmt; 2454 int read = format_decode(fmt, &spec); 2455 2456 fmt += read; 2457 2458 switch (spec.type) { 2459 case FORMAT_TYPE_NONE: { 2460 int copy = read; 2461 if (str < end) { 2462 if (copy > end - str) 2463 copy = end - str; 2464 memcpy(str, old_fmt, copy); 2465 } 2466 str += read; 2467 break; 2468 } 2469 2470 case FORMAT_TYPE_WIDTH: 2471 set_field_width(&spec, va_arg(args, int)); 2472 break; 2473 2474 case FORMAT_TYPE_PRECISION: 2475 set_precision(&spec, va_arg(args, int)); 2476 break; 2477 2478 case FORMAT_TYPE_CHAR: { 2479 char c; 2480 2481 if (!(spec.flags & LEFT)) { 2482 while (--spec.field_width > 0) { 2483 if (str < end) 2484 *str = ' '; 2485 ++str; 2486 2487 } 2488 } 2489 c = (unsigned char) va_arg(args, int); 2490 if (str < end) 2491 *str = c; 2492 ++str; 2493 while (--spec.field_width > 0) { 2494 if (str < end) 2495 *str = ' '; 2496 ++str; 2497 } 2498 break; 2499 } 2500 2501 case FORMAT_TYPE_STR: 2502 str = string(str, end, va_arg(args, char *), spec); 2503 break; 2504 2505 case FORMAT_TYPE_PTR: 2506 str = pointer(fmt, str, end, va_arg(args, void *), 2507 spec); 2508 while (isalnum(*fmt)) 2509 fmt++; 2510 break; 2511 2512 case FORMAT_TYPE_PERCENT_CHAR: 2513 if (str < end) 2514 *str = '%'; 2515 ++str; 2516 break; 2517 2518 case FORMAT_TYPE_INVALID: 2519 /* 2520 * Presumably the arguments passed gcc's type 2521 * checking, but there is no safe or sane way 2522 * for us to continue parsing the format and 2523 * fetching from the va_list; the remaining 2524 * specifiers and arguments would be out of 2525 * sync. 2526 */ 2527 goto out; 2528 2529 default: 2530 switch (spec.type) { 2531 case FORMAT_TYPE_LONG_LONG: 2532 num = va_arg(args, long long); 2533 break; 2534 case FORMAT_TYPE_ULONG: 2535 num = va_arg(args, unsigned long); 2536 break; 2537 case FORMAT_TYPE_LONG: 2538 num = va_arg(args, long); 2539 break; 2540 case FORMAT_TYPE_SIZE_T: 2541 if (spec.flags & SIGN) 2542 num = va_arg(args, ssize_t); 2543 else 2544 num = va_arg(args, size_t); 2545 break; 2546 case FORMAT_TYPE_PTRDIFF: 2547 num = va_arg(args, ptrdiff_t); 2548 break; 2549 case FORMAT_TYPE_UBYTE: 2550 num = (unsigned char) va_arg(args, int); 2551 break; 2552 case FORMAT_TYPE_BYTE: 2553 num = (signed char) va_arg(args, int); 2554 break; 2555 case FORMAT_TYPE_USHORT: 2556 num = (unsigned short) va_arg(args, int); 2557 break; 2558 case FORMAT_TYPE_SHORT: 2559 num = (short) va_arg(args, int); 2560 break; 2561 case FORMAT_TYPE_INT: 2562 num = (int) va_arg(args, int); 2563 break; 2564 default: 2565 num = va_arg(args, unsigned int); 2566 } 2567 2568 str = number(str, end, num, spec); 2569 } 2570 } 2571 2572 out: 2573 if (size > 0) { 2574 if (str < end) 2575 *str = '\0'; 2576 else 2577 end[-1] = '\0'; 2578 } 2579 2580 /* the trailing null byte doesn't count towards the total */ 2581 return str-buf; 2582 2583 } 2584 EXPORT_SYMBOL(vsnprintf); 2585 2586 /** 2587 * vscnprintf - Format a string and place it in a buffer 2588 * @buf: The buffer to place the result into 2589 * @size: The size of the buffer, including the trailing null space 2590 * @fmt: The format string to use 2591 * @args: Arguments for the format string 2592 * 2593 * The return value is the number of characters which have been written into 2594 * the @buf not including the trailing '\0'. If @size is == 0 the function 2595 * returns 0. 2596 * 2597 * If you're not already dealing with a va_list consider using scnprintf(). 2598 * 2599 * See the vsnprintf() documentation for format string extensions over C99. 2600 */ 2601 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 2602 { 2603 int i; 2604 2605 i = vsnprintf(buf, size, fmt, args); 2606 2607 if (likely(i < size)) 2608 return i; 2609 if (size != 0) 2610 return size - 1; 2611 return 0; 2612 } 2613 EXPORT_SYMBOL(vscnprintf); 2614 2615 /** 2616 * snprintf - Format a string and place it in a buffer 2617 * @buf: The buffer to place the result into 2618 * @size: The size of the buffer, including the trailing null space 2619 * @fmt: The format string to use 2620 * @...: Arguments for the format string 2621 * 2622 * The return value is the number of characters which would be 2623 * generated for the given input, excluding the trailing null, 2624 * as per ISO C99. If the return is greater than or equal to 2625 * @size, the resulting string is truncated. 2626 * 2627 * See the vsnprintf() documentation for format string extensions over C99. 2628 */ 2629 int snprintf(char *buf, size_t size, const char *fmt, ...) 2630 { 2631 va_list args; 2632 int i; 2633 2634 va_start(args, fmt); 2635 i = vsnprintf(buf, size, fmt, args); 2636 va_end(args); 2637 2638 return i; 2639 } 2640 EXPORT_SYMBOL(snprintf); 2641 2642 /** 2643 * scnprintf - Format a string and place it in a buffer 2644 * @buf: The buffer to place the result into 2645 * @size: The size of the buffer, including the trailing null space 2646 * @fmt: The format string to use 2647 * @...: Arguments for the format string 2648 * 2649 * The return value is the number of characters written into @buf not including 2650 * the trailing '\0'. If @size is == 0 the function returns 0. 2651 */ 2652 2653 int scnprintf(char *buf, size_t size, const char *fmt, ...) 2654 { 2655 va_list args; 2656 int i; 2657 2658 va_start(args, fmt); 2659 i = vscnprintf(buf, size, fmt, args); 2660 va_end(args); 2661 2662 return i; 2663 } 2664 EXPORT_SYMBOL(scnprintf); 2665 2666 /** 2667 * vsprintf - Format a string and place it in a buffer 2668 * @buf: The buffer to place the result into 2669 * @fmt: The format string to use 2670 * @args: Arguments for the format string 2671 * 2672 * The function returns the number of characters written 2673 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 2674 * buffer overflows. 2675 * 2676 * If you're not already dealing with a va_list consider using sprintf(). 2677 * 2678 * See the vsnprintf() documentation for format string extensions over C99. 2679 */ 2680 int vsprintf(char *buf, const char *fmt, va_list args) 2681 { 2682 return vsnprintf(buf, INT_MAX, fmt, args); 2683 } 2684 EXPORT_SYMBOL(vsprintf); 2685 2686 /** 2687 * sprintf - Format a string and place it in a buffer 2688 * @buf: The buffer to place the result into 2689 * @fmt: The format string to use 2690 * @...: Arguments for the format string 2691 * 2692 * The function returns the number of characters written 2693 * into @buf. Use snprintf() or scnprintf() in order to avoid 2694 * buffer overflows. 2695 * 2696 * See the vsnprintf() documentation for format string extensions over C99. 2697 */ 2698 int sprintf(char *buf, const char *fmt, ...) 2699 { 2700 va_list args; 2701 int i; 2702 2703 va_start(args, fmt); 2704 i = vsnprintf(buf, INT_MAX, fmt, args); 2705 va_end(args); 2706 2707 return i; 2708 } 2709 EXPORT_SYMBOL(sprintf); 2710 2711 #ifdef CONFIG_BINARY_PRINTF 2712 /* 2713 * bprintf service: 2714 * vbin_printf() - VA arguments to binary data 2715 * bstr_printf() - Binary data to text string 2716 */ 2717 2718 /** 2719 * vbin_printf - Parse a format string and place args' binary value in a buffer 2720 * @bin_buf: The buffer to place args' binary value 2721 * @size: The size of the buffer(by words(32bits), not characters) 2722 * @fmt: The format string to use 2723 * @args: Arguments for the format string 2724 * 2725 * The format follows C99 vsnprintf, except %n is ignored, and its argument 2726 * is skipped. 2727 * 2728 * The return value is the number of words(32bits) which would be generated for 2729 * the given input. 2730 * 2731 * NOTE: 2732 * If the return value is greater than @size, the resulting bin_buf is NOT 2733 * valid for bstr_printf(). 2734 */ 2735 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 2736 { 2737 struct printf_spec spec = {0}; 2738 char *str, *end; 2739 int width; 2740 2741 str = (char *)bin_buf; 2742 end = (char *)(bin_buf + size); 2743 2744 #define save_arg(type) \ 2745 ({ \ 2746 unsigned long long value; \ 2747 if (sizeof(type) == 8) { \ 2748 unsigned long long val8; \ 2749 str = PTR_ALIGN(str, sizeof(u32)); \ 2750 val8 = va_arg(args, unsigned long long); \ 2751 if (str + sizeof(type) <= end) { \ 2752 *(u32 *)str = *(u32 *)&val8; \ 2753 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ 2754 } \ 2755 value = val8; \ 2756 } else { \ 2757 unsigned int val4; \ 2758 str = PTR_ALIGN(str, sizeof(type)); \ 2759 val4 = va_arg(args, int); \ 2760 if (str + sizeof(type) <= end) \ 2761 *(typeof(type) *)str = (type)(long)val4; \ 2762 value = (unsigned long long)val4; \ 2763 } \ 2764 str += sizeof(type); \ 2765 value; \ 2766 }) 2767 2768 while (*fmt) { 2769 int read = format_decode(fmt, &spec); 2770 2771 fmt += read; 2772 2773 switch (spec.type) { 2774 case FORMAT_TYPE_NONE: 2775 case FORMAT_TYPE_PERCENT_CHAR: 2776 break; 2777 case FORMAT_TYPE_INVALID: 2778 goto out; 2779 2780 case FORMAT_TYPE_WIDTH: 2781 case FORMAT_TYPE_PRECISION: 2782 width = (int)save_arg(int); 2783 /* Pointers may require the width */ 2784 if (*fmt == 'p') 2785 set_field_width(&spec, width); 2786 break; 2787 2788 case FORMAT_TYPE_CHAR: 2789 save_arg(char); 2790 break; 2791 2792 case FORMAT_TYPE_STR: { 2793 const char *save_str = va_arg(args, char *); 2794 const char *err_msg; 2795 size_t len; 2796 2797 err_msg = check_pointer_msg(save_str); 2798 if (err_msg) 2799 save_str = err_msg; 2800 2801 len = strlen(save_str) + 1; 2802 if (str + len < end) 2803 memcpy(str, save_str, len); 2804 str += len; 2805 break; 2806 } 2807 2808 case FORMAT_TYPE_PTR: 2809 /* Dereferenced pointers must be done now */ 2810 switch (*fmt) { 2811 /* Dereference of functions is still OK */ 2812 case 'S': 2813 case 's': 2814 case 'F': 2815 case 'f': 2816 case 'x': 2817 case 'K': 2818 save_arg(void *); 2819 break; 2820 default: 2821 if (!isalnum(*fmt)) { 2822 save_arg(void *); 2823 break; 2824 } 2825 str = pointer(fmt, str, end, va_arg(args, void *), 2826 spec); 2827 if (str + 1 < end) 2828 *str++ = '\0'; 2829 else 2830 end[-1] = '\0'; /* Must be nul terminated */ 2831 } 2832 /* skip all alphanumeric pointer suffixes */ 2833 while (isalnum(*fmt)) 2834 fmt++; 2835 break; 2836 2837 default: 2838 switch (spec.type) { 2839 2840 case FORMAT_TYPE_LONG_LONG: 2841 save_arg(long long); 2842 break; 2843 case FORMAT_TYPE_ULONG: 2844 case FORMAT_TYPE_LONG: 2845 save_arg(unsigned long); 2846 break; 2847 case FORMAT_TYPE_SIZE_T: 2848 save_arg(size_t); 2849 break; 2850 case FORMAT_TYPE_PTRDIFF: 2851 save_arg(ptrdiff_t); 2852 break; 2853 case FORMAT_TYPE_UBYTE: 2854 case FORMAT_TYPE_BYTE: 2855 save_arg(char); 2856 break; 2857 case FORMAT_TYPE_USHORT: 2858 case FORMAT_TYPE_SHORT: 2859 save_arg(short); 2860 break; 2861 default: 2862 save_arg(int); 2863 } 2864 } 2865 } 2866 2867 out: 2868 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 2869 #undef save_arg 2870 } 2871 EXPORT_SYMBOL_GPL(vbin_printf); 2872 2873 /** 2874 * bstr_printf - Format a string from binary arguments and place it in a buffer 2875 * @buf: The buffer to place the result into 2876 * @size: The size of the buffer, including the trailing null space 2877 * @fmt: The format string to use 2878 * @bin_buf: Binary arguments for the format string 2879 * 2880 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 2881 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 2882 * a binary buffer that generated by vbin_printf. 2883 * 2884 * The format follows C99 vsnprintf, but has some extensions: 2885 * see vsnprintf comment for details. 2886 * 2887 * The return value is the number of characters which would 2888 * be generated for the given input, excluding the trailing 2889 * '\0', as per ISO C99. If you want to have the exact 2890 * number of characters written into @buf as return value 2891 * (not including the trailing '\0'), use vscnprintf(). If the 2892 * return is greater than or equal to @size, the resulting 2893 * string is truncated. 2894 */ 2895 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 2896 { 2897 struct printf_spec spec = {0}; 2898 char *str, *end; 2899 const char *args = (const char *)bin_buf; 2900 2901 if (WARN_ON_ONCE(size > INT_MAX)) 2902 return 0; 2903 2904 str = buf; 2905 end = buf + size; 2906 2907 #define get_arg(type) \ 2908 ({ \ 2909 typeof(type) value; \ 2910 if (sizeof(type) == 8) { \ 2911 args = PTR_ALIGN(args, sizeof(u32)); \ 2912 *(u32 *)&value = *(u32 *)args; \ 2913 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 2914 } else { \ 2915 args = PTR_ALIGN(args, sizeof(type)); \ 2916 value = *(typeof(type) *)args; \ 2917 } \ 2918 args += sizeof(type); \ 2919 value; \ 2920 }) 2921 2922 /* Make sure end is always >= buf */ 2923 if (end < buf) { 2924 end = ((void *)-1); 2925 size = end - buf; 2926 } 2927 2928 while (*fmt) { 2929 const char *old_fmt = fmt; 2930 int read = format_decode(fmt, &spec); 2931 2932 fmt += read; 2933 2934 switch (spec.type) { 2935 case FORMAT_TYPE_NONE: { 2936 int copy = read; 2937 if (str < end) { 2938 if (copy > end - str) 2939 copy = end - str; 2940 memcpy(str, old_fmt, copy); 2941 } 2942 str += read; 2943 break; 2944 } 2945 2946 case FORMAT_TYPE_WIDTH: 2947 set_field_width(&spec, get_arg(int)); 2948 break; 2949 2950 case FORMAT_TYPE_PRECISION: 2951 set_precision(&spec, get_arg(int)); 2952 break; 2953 2954 case FORMAT_TYPE_CHAR: { 2955 char c; 2956 2957 if (!(spec.flags & LEFT)) { 2958 while (--spec.field_width > 0) { 2959 if (str < end) 2960 *str = ' '; 2961 ++str; 2962 } 2963 } 2964 c = (unsigned char) get_arg(char); 2965 if (str < end) 2966 *str = c; 2967 ++str; 2968 while (--spec.field_width > 0) { 2969 if (str < end) 2970 *str = ' '; 2971 ++str; 2972 } 2973 break; 2974 } 2975 2976 case FORMAT_TYPE_STR: { 2977 const char *str_arg = args; 2978 args += strlen(str_arg) + 1; 2979 str = string(str, end, (char *)str_arg, spec); 2980 break; 2981 } 2982 2983 case FORMAT_TYPE_PTR: { 2984 bool process = false; 2985 int copy, len; 2986 /* Non function dereferences were already done */ 2987 switch (*fmt) { 2988 case 'S': 2989 case 's': 2990 case 'F': 2991 case 'f': 2992 case 'x': 2993 case 'K': 2994 process = true; 2995 break; 2996 default: 2997 if (!isalnum(*fmt)) { 2998 process = true; 2999 break; 3000 } 3001 /* Pointer dereference was already processed */ 3002 if (str < end) { 3003 len = copy = strlen(args); 3004 if (copy > end - str) 3005 copy = end - str; 3006 memcpy(str, args, copy); 3007 str += len; 3008 args += len + 1; 3009 } 3010 } 3011 if (process) 3012 str = pointer(fmt, str, end, get_arg(void *), spec); 3013 3014 while (isalnum(*fmt)) 3015 fmt++; 3016 break; 3017 } 3018 3019 case FORMAT_TYPE_PERCENT_CHAR: 3020 if (str < end) 3021 *str = '%'; 3022 ++str; 3023 break; 3024 3025 case FORMAT_TYPE_INVALID: 3026 goto out; 3027 3028 default: { 3029 unsigned long long num; 3030 3031 switch (spec.type) { 3032 3033 case FORMAT_TYPE_LONG_LONG: 3034 num = get_arg(long long); 3035 break; 3036 case FORMAT_TYPE_ULONG: 3037 case FORMAT_TYPE_LONG: 3038 num = get_arg(unsigned long); 3039 break; 3040 case FORMAT_TYPE_SIZE_T: 3041 num = get_arg(size_t); 3042 break; 3043 case FORMAT_TYPE_PTRDIFF: 3044 num = get_arg(ptrdiff_t); 3045 break; 3046 case FORMAT_TYPE_UBYTE: 3047 num = get_arg(unsigned char); 3048 break; 3049 case FORMAT_TYPE_BYTE: 3050 num = get_arg(signed char); 3051 break; 3052 case FORMAT_TYPE_USHORT: 3053 num = get_arg(unsigned short); 3054 break; 3055 case FORMAT_TYPE_SHORT: 3056 num = get_arg(short); 3057 break; 3058 case FORMAT_TYPE_UINT: 3059 num = get_arg(unsigned int); 3060 break; 3061 default: 3062 num = get_arg(int); 3063 } 3064 3065 str = number(str, end, num, spec); 3066 } /* default: */ 3067 } /* switch(spec.type) */ 3068 } /* while(*fmt) */ 3069 3070 out: 3071 if (size > 0) { 3072 if (str < end) 3073 *str = '\0'; 3074 else 3075 end[-1] = '\0'; 3076 } 3077 3078 #undef get_arg 3079 3080 /* the trailing null byte doesn't count towards the total */ 3081 return str - buf; 3082 } 3083 EXPORT_SYMBOL_GPL(bstr_printf); 3084 3085 /** 3086 * bprintf - Parse a format string and place args' binary value in a buffer 3087 * @bin_buf: The buffer to place args' binary value 3088 * @size: The size of the buffer(by words(32bits), not characters) 3089 * @fmt: The format string to use 3090 * @...: Arguments for the format string 3091 * 3092 * The function returns the number of words(u32) written 3093 * into @bin_buf. 3094 */ 3095 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 3096 { 3097 va_list args; 3098 int ret; 3099 3100 va_start(args, fmt); 3101 ret = vbin_printf(bin_buf, size, fmt, args); 3102 va_end(args); 3103 3104 return ret; 3105 } 3106 EXPORT_SYMBOL_GPL(bprintf); 3107 3108 #endif /* CONFIG_BINARY_PRINTF */ 3109 3110 /** 3111 * vsscanf - Unformat a buffer into a list of arguments 3112 * @buf: input buffer 3113 * @fmt: format of buffer 3114 * @args: arguments 3115 */ 3116 int vsscanf(const char *buf, const char *fmt, va_list args) 3117 { 3118 const char *str = buf; 3119 char *next; 3120 char digit; 3121 int num = 0; 3122 u8 qualifier; 3123 unsigned int base; 3124 union { 3125 long long s; 3126 unsigned long long u; 3127 } val; 3128 s16 field_width; 3129 bool is_sign; 3130 3131 while (*fmt) { 3132 /* skip any white space in format */ 3133 /* white space in format matchs any amount of 3134 * white space, including none, in the input. 3135 */ 3136 if (isspace(*fmt)) { 3137 fmt = skip_spaces(++fmt); 3138 str = skip_spaces(str); 3139 } 3140 3141 /* anything that is not a conversion must match exactly */ 3142 if (*fmt != '%' && *fmt) { 3143 if (*fmt++ != *str++) 3144 break; 3145 continue; 3146 } 3147 3148 if (!*fmt) 3149 break; 3150 ++fmt; 3151 3152 /* skip this conversion. 3153 * advance both strings to next white space 3154 */ 3155 if (*fmt == '*') { 3156 if (!*str) 3157 break; 3158 while (!isspace(*fmt) && *fmt != '%' && *fmt) { 3159 /* '%*[' not yet supported, invalid format */ 3160 if (*fmt == '[') 3161 return num; 3162 fmt++; 3163 } 3164 while (!isspace(*str) && *str) 3165 str++; 3166 continue; 3167 } 3168 3169 /* get field width */ 3170 field_width = -1; 3171 if (isdigit(*fmt)) { 3172 field_width = skip_atoi(&fmt); 3173 if (field_width <= 0) 3174 break; 3175 } 3176 3177 /* get conversion qualifier */ 3178 qualifier = -1; 3179 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 3180 *fmt == 'z') { 3181 qualifier = *fmt++; 3182 if (unlikely(qualifier == *fmt)) { 3183 if (qualifier == 'h') { 3184 qualifier = 'H'; 3185 fmt++; 3186 } else if (qualifier == 'l') { 3187 qualifier = 'L'; 3188 fmt++; 3189 } 3190 } 3191 } 3192 3193 if (!*fmt) 3194 break; 3195 3196 if (*fmt == 'n') { 3197 /* return number of characters read so far */ 3198 *va_arg(args, int *) = str - buf; 3199 ++fmt; 3200 continue; 3201 } 3202 3203 if (!*str) 3204 break; 3205 3206 base = 10; 3207 is_sign = false; 3208 3209 switch (*fmt++) { 3210 case 'c': 3211 { 3212 char *s = (char *)va_arg(args, char*); 3213 if (field_width == -1) 3214 field_width = 1; 3215 do { 3216 *s++ = *str++; 3217 } while (--field_width > 0 && *str); 3218 num++; 3219 } 3220 continue; 3221 case 's': 3222 { 3223 char *s = (char *)va_arg(args, char *); 3224 if (field_width == -1) 3225 field_width = SHRT_MAX; 3226 /* first, skip leading white space in buffer */ 3227 str = skip_spaces(str); 3228 3229 /* now copy until next white space */ 3230 while (*str && !isspace(*str) && field_width--) 3231 *s++ = *str++; 3232 *s = '\0'; 3233 num++; 3234 } 3235 continue; 3236 /* 3237 * Warning: This implementation of the '[' conversion specifier 3238 * deviates from its glibc counterpart in the following ways: 3239 * (1) It does NOT support ranges i.e. '-' is NOT a special 3240 * character 3241 * (2) It cannot match the closing bracket ']' itself 3242 * (3) A field width is required 3243 * (4) '%*[' (discard matching input) is currently not supported 3244 * 3245 * Example usage: 3246 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", 3247 * buf1, buf2, buf3); 3248 * if (ret < 3) 3249 * // etc.. 3250 */ 3251 case '[': 3252 { 3253 char *s = (char *)va_arg(args, char *); 3254 DECLARE_BITMAP(set, 256) = {0}; 3255 unsigned int len = 0; 3256 bool negate = (*fmt == '^'); 3257 3258 /* field width is required */ 3259 if (field_width == -1) 3260 return num; 3261 3262 if (negate) 3263 ++fmt; 3264 3265 for ( ; *fmt && *fmt != ']'; ++fmt, ++len) 3266 set_bit((u8)*fmt, set); 3267 3268 /* no ']' or no character set found */ 3269 if (!*fmt || !len) 3270 return num; 3271 ++fmt; 3272 3273 if (negate) { 3274 bitmap_complement(set, set, 256); 3275 /* exclude null '\0' byte */ 3276 clear_bit(0, set); 3277 } 3278 3279 /* match must be non-empty */ 3280 if (!test_bit((u8)*str, set)) 3281 return num; 3282 3283 while (test_bit((u8)*str, set) && field_width--) 3284 *s++ = *str++; 3285 *s = '\0'; 3286 ++num; 3287 } 3288 continue; 3289 case 'o': 3290 base = 8; 3291 break; 3292 case 'x': 3293 case 'X': 3294 base = 16; 3295 break; 3296 case 'i': 3297 base = 0; 3298 /* fall through */ 3299 case 'd': 3300 is_sign = true; 3301 /* fall through */ 3302 case 'u': 3303 break; 3304 case '%': 3305 /* looking for '%' in str */ 3306 if (*str++ != '%') 3307 return num; 3308 continue; 3309 default: 3310 /* invalid format; stop here */ 3311 return num; 3312 } 3313 3314 /* have some sort of integer conversion. 3315 * first, skip white space in buffer. 3316 */ 3317 str = skip_spaces(str); 3318 3319 digit = *str; 3320 if (is_sign && digit == '-') 3321 digit = *(str + 1); 3322 3323 if (!digit 3324 || (base == 16 && !isxdigit(digit)) 3325 || (base == 10 && !isdigit(digit)) 3326 || (base == 8 && (!isdigit(digit) || digit > '7')) 3327 || (base == 0 && !isdigit(digit))) 3328 break; 3329 3330 if (is_sign) 3331 val.s = qualifier != 'L' ? 3332 simple_strtol(str, &next, base) : 3333 simple_strtoll(str, &next, base); 3334 else 3335 val.u = qualifier != 'L' ? 3336 simple_strtoul(str, &next, base) : 3337 simple_strtoull(str, &next, base); 3338 3339 if (field_width > 0 && next - str > field_width) { 3340 if (base == 0) 3341 _parse_integer_fixup_radix(str, &base); 3342 while (next - str > field_width) { 3343 if (is_sign) 3344 val.s = div_s64(val.s, base); 3345 else 3346 val.u = div_u64(val.u, base); 3347 --next; 3348 } 3349 } 3350 3351 switch (qualifier) { 3352 case 'H': /* that's 'hh' in format */ 3353 if (is_sign) 3354 *va_arg(args, signed char *) = val.s; 3355 else 3356 *va_arg(args, unsigned char *) = val.u; 3357 break; 3358 case 'h': 3359 if (is_sign) 3360 *va_arg(args, short *) = val.s; 3361 else 3362 *va_arg(args, unsigned short *) = val.u; 3363 break; 3364 case 'l': 3365 if (is_sign) 3366 *va_arg(args, long *) = val.s; 3367 else 3368 *va_arg(args, unsigned long *) = val.u; 3369 break; 3370 case 'L': 3371 if (is_sign) 3372 *va_arg(args, long long *) = val.s; 3373 else 3374 *va_arg(args, unsigned long long *) = val.u; 3375 break; 3376 case 'z': 3377 *va_arg(args, size_t *) = val.u; 3378 break; 3379 default: 3380 if (is_sign) 3381 *va_arg(args, int *) = val.s; 3382 else 3383 *va_arg(args, unsigned int *) = val.u; 3384 break; 3385 } 3386 num++; 3387 3388 if (!next) 3389 break; 3390 str = next; 3391 } 3392 3393 return num; 3394 } 3395 EXPORT_SYMBOL(vsscanf); 3396 3397 /** 3398 * sscanf - Unformat a buffer into a list of arguments 3399 * @buf: input buffer 3400 * @fmt: formatting of buffer 3401 * @...: resulting arguments 3402 */ 3403 int sscanf(const char *buf, const char *fmt, ...) 3404 { 3405 va_list args; 3406 int i; 3407 3408 va_start(args, fmt); 3409 i = vsscanf(buf, fmt, args); 3410 va_end(args); 3411 3412 return i; 3413 } 3414 EXPORT_SYMBOL(sscanf); 3415