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pointer to the end of the parsed string will be placed here 56 * @base: The number base to use 57 * 58 * This function is obsolete.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pointer to the end of the parsed string will be placed here 81 * @base: The number base to use 82 * 83 * This function is obsolete.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