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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/clk.h>
21#include <linux/clk-provider.h>
22#include <linux/module.h> /* for KSYM_SYMBOL_LEN */
23#include <linux/types.h>
24#include <linux/string.h>
25#include <linux/ctype.h>
26#include <linux/kernel.h>
27#include <linux/kallsyms.h>
28#include <linux/math64.h>
29#include <linux/uaccess.h>
30#include <linux/ioport.h>
31#include <linux/dcache.h>
32#include <linux/cred.h>
33#include <linux/uuid.h>
34#include <net/addrconf.h>
35#ifdef CONFIG_BLOCK
36#include <linux/blkdev.h>
37#endif
38
39#include "../mm/internal.h" /* For the trace_print_flags arrays */
40
41#include <asm/page.h> /* for PAGE_SIZE */
42#include <asm/sections.h> /* for dereference_function_descriptor() */
43#include <asm/byteorder.h> /* cpu_to_le16 */
44
45#include <linux/string_helpers.h>
46#include "kstrtox.h"
47
48/**
49 * simple_strtoull - convert a string to an unsigned long long
50 * @cp: The start of the string
51 * @endp: A pointer to the end of the parsed string will be placed here
52 * @base: The number base to use
53 *
54 * This function is obsolete. Please use kstrtoull instead.
55 */
56unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
57{
58 unsigned long long result;
59 unsigned int rv;
60
61 cp = _parse_integer_fixup_radix(cp, &base);
62 rv = _parse_integer(cp, base, &result);
63 /* FIXME */
64 cp += (rv & ~KSTRTOX_OVERFLOW);
65
66 if (endp)
67 *endp = (char *)cp;
68
69 return result;
70}
71EXPORT_SYMBOL(simple_strtoull);
72
73/**
74 * simple_strtoul - convert a string to an unsigned long
75 * @cp: The start of the string
76 * @endp: A pointer to the end of the parsed string will be placed here
77 * @base: The number base to use
78 *
79 * This function is obsolete. Please use kstrtoul instead.
80 */
81unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
82{
83 return simple_strtoull(cp, endp, base);
84}
85EXPORT_SYMBOL(simple_strtoul);
86
87/**
88 * simple_strtol - convert a string to a signed long
89 * @cp: The start of the string
90 * @endp: A pointer to the end of the parsed string will be placed here
91 * @base: The number base to use
92 *
93 * This function is obsolete. Please use kstrtol instead.
94 */
95long simple_strtol(const char *cp, char **endp, unsigned int base)
96{
97 if (*cp == '-')
98 return -simple_strtoul(cp + 1, endp, base);
99
100 return simple_strtoul(cp, endp, base);
101}
102EXPORT_SYMBOL(simple_strtol);
103
104/**
105 * simple_strtoll - convert a string to a signed long long
106 * @cp: The start of the string
107 * @endp: A pointer to the end of the parsed string will be placed here
108 * @base: The number base to use
109 *
110 * This function is obsolete. Please use kstrtoll instead.
111 */
112long long simple_strtoll(const char *cp, char **endp, unsigned int base)
113{
114 if (*cp == '-')
115 return -simple_strtoull(cp + 1, endp, base);
116
117 return simple_strtoull(cp, endp, base);
118}
119EXPORT_SYMBOL(simple_strtoll);
120
121static noinline_for_stack
122int skip_atoi(const char **s)
123{
124 int i = 0;
125
126 do {
127 i = i*10 + *((*s)++) - '0';
128 } while (isdigit(**s));
129
130 return i;
131}
132
133/*
134 * Decimal conversion is by far the most typical, and is used for
135 * /proc and /sys data. This directly impacts e.g. top performance
136 * with many processes running. We optimize it for speed by emitting
137 * two characters at a time, using a 200 byte lookup table. This
138 * roughly halves the number of multiplications compared to computing
139 * the digits one at a time. Implementation strongly inspired by the
140 * previous version, which in turn used ideas described at
141 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
142 * from the author, Douglas W. Jones).
143 *
144 * It turns out there is precisely one 26 bit fixed-point
145 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
146 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
147 * range happens to be somewhat larger (x <= 1073741898), but that's
148 * irrelevant for our purpose.
149 *
150 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
151 * need a 32x32->64 bit multiply, so we simply use the same constant.
152 *
153 * For dividing a number in the range [100, 10^4-1] by 100, there are
154 * several options. The simplest is (x * 0x147b) >> 19, which is valid
155 * for all x <= 43698.
156 */
157
158static const u16 decpair[100] = {
159#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
160 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
161 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
162 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
163 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
164 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
165 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
166 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
167 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
168 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
169 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
170#undef _
171};
172
173/*
174 * This will print a single '0' even if r == 0, since we would
175 * immediately jump to out_r where two 0s would be written but only
176 * one of them accounted for in buf. This is needed by ip4_string
177 * below. All other callers pass a non-zero value of r.
178*/
179static noinline_for_stack
180char *put_dec_trunc8(char *buf, unsigned r)
181{
182 unsigned q;
183
184 /* 1 <= r < 10^8 */
185 if (r < 100)
186 goto out_r;
187
188 /* 100 <= r < 10^8 */
189 q = (r * (u64)0x28f5c29) >> 32;
190 *((u16 *)buf) = decpair[r - 100*q];
191 buf += 2;
192
193 /* 1 <= q < 10^6 */
194 if (q < 100)
195 goto out_q;
196
197 /* 100 <= q < 10^6 */
198 r = (q * (u64)0x28f5c29) >> 32;
199 *((u16 *)buf) = decpair[q - 100*r];
200 buf += 2;
201
202 /* 1 <= r < 10^4 */
203 if (r < 100)
204 goto out_r;
205
206 /* 100 <= r < 10^4 */
207 q = (r * 0x147b) >> 19;
208 *((u16 *)buf) = decpair[r - 100*q];
209 buf += 2;
210out_q:
211 /* 1 <= q < 100 */
212 r = q;
213out_r:
214 /* 1 <= r < 100 */
215 *((u16 *)buf) = decpair[r];
216 buf += r < 10 ? 1 : 2;
217 return buf;
218}
219
220#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
221static noinline_for_stack
222char *put_dec_full8(char *buf, unsigned r)
223{
224 unsigned q;
225
226 /* 0 <= r < 10^8 */
227 q = (r * (u64)0x28f5c29) >> 32;
228 *((u16 *)buf) = decpair[r - 100*q];
229 buf += 2;
230
231 /* 0 <= q < 10^6 */
232 r = (q * (u64)0x28f5c29) >> 32;
233 *((u16 *)buf) = decpair[q - 100*r];
234 buf += 2;
235
236 /* 0 <= r < 10^4 */
237 q = (r * 0x147b) >> 19;
238 *((u16 *)buf) = decpair[r - 100*q];
239 buf += 2;
240
241 /* 0 <= q < 100 */
242 *((u16 *)buf) = decpair[q];
243 buf += 2;
244 return buf;
245}
246
247static noinline_for_stack
248char *put_dec(char *buf, unsigned long long n)
249{
250 if (n >= 100*1000*1000)
251 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
252 /* 1 <= n <= 1.6e11 */
253 if (n >= 100*1000*1000)
254 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
255 /* 1 <= n < 1e8 */
256 return put_dec_trunc8(buf, n);
257}
258
259#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
260
261static void
262put_dec_full4(char *buf, unsigned r)
263{
264 unsigned q;
265
266 /* 0 <= r < 10^4 */
267 q = (r * 0x147b) >> 19;
268 *((u16 *)buf) = decpair[r - 100*q];
269 buf += 2;
270 /* 0 <= q < 100 */
271 *((u16 *)buf) = decpair[q];
272}
273
274/*
275 * Call put_dec_full4 on x % 10000, return x / 10000.
276 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
277 * holds for all x < 1,128,869,999. The largest value this
278 * helper will ever be asked to convert is 1,125,520,955.
279 * (second call in the put_dec code, assuming n is all-ones).
280 */
281static noinline_for_stack
282unsigned put_dec_helper4(char *buf, unsigned x)
283{
284 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
285
286 put_dec_full4(buf, x - q * 10000);
287 return q;
288}
289
290/* Based on code by Douglas W. Jones found at
291 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
292 * (with permission from the author).
293 * Performs no 64-bit division and hence should be fast on 32-bit machines.
294 */
295static
296char *put_dec(char *buf, unsigned long long n)
297{
298 uint32_t d3, d2, d1, q, h;
299
300 if (n < 100*1000*1000)
301 return put_dec_trunc8(buf, n);
302
303 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
304 h = (n >> 32);
305 d2 = (h ) & 0xffff;
306 d3 = (h >> 16); /* implicit "& 0xffff" */
307
308 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
309 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
310 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
311 q = put_dec_helper4(buf, q);
312
313 q += 7671 * d3 + 9496 * d2 + 6 * d1;
314 q = put_dec_helper4(buf+4, q);
315
316 q += 4749 * d3 + 42 * d2;
317 q = put_dec_helper4(buf+8, q);
318
319 q += 281 * d3;
320 buf += 12;
321 if (q)
322 buf = put_dec_trunc8(buf, q);
323 else while (buf[-1] == '0')
324 --buf;
325
326 return buf;
327}
328
329#endif
330
331/*
332 * Convert passed number to decimal string.
333 * Returns the length of string. On buffer overflow, returns 0.
334 *
335 * If speed is not important, use snprintf(). It's easy to read the code.
336 */
337int num_to_str(char *buf, int size, unsigned long long num)
338{
339 /* put_dec requires 2-byte alignment of the buffer. */
340 char tmp[sizeof(num) * 3] __aligned(2);
341 int idx, len;
342
343 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
344 if (num <= 9) {
345 tmp[0] = '0' + num;
346 len = 1;
347 } else {
348 len = put_dec(tmp, num) - tmp;
349 }
350
351 if (len > size)
352 return 0;
353 for (idx = 0; idx < len; ++idx)
354 buf[idx] = tmp[len - idx - 1];
355 return len;
356}
357
358#define SIGN 1 /* unsigned/signed, must be 1 */
359#define LEFT 2 /* left justified */
360#define PLUS 4 /* show plus */
361#define SPACE 8 /* space if plus */
362#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
363#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
364#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
365
366enum format_type {
367 FORMAT_TYPE_NONE, /* Just a string part */
368 FORMAT_TYPE_WIDTH,
369 FORMAT_TYPE_PRECISION,
370 FORMAT_TYPE_CHAR,
371 FORMAT_TYPE_STR,
372 FORMAT_TYPE_PTR,
373 FORMAT_TYPE_PERCENT_CHAR,
374 FORMAT_TYPE_INVALID,
375 FORMAT_TYPE_LONG_LONG,
376 FORMAT_TYPE_ULONG,
377 FORMAT_TYPE_LONG,
378 FORMAT_TYPE_UBYTE,
379 FORMAT_TYPE_BYTE,
380 FORMAT_TYPE_USHORT,
381 FORMAT_TYPE_SHORT,
382 FORMAT_TYPE_UINT,
383 FORMAT_TYPE_INT,
384 FORMAT_TYPE_SIZE_T,
385 FORMAT_TYPE_PTRDIFF
386};
387
388struct printf_spec {
389 unsigned int type:8; /* format_type enum */
390 signed int field_width:24; /* width of output field */
391 unsigned int flags:8; /* flags to number() */
392 unsigned int base:8; /* number base, 8, 10 or 16 only */
393 signed int precision:16; /* # of digits/chars */
394} __packed;
395#define FIELD_WIDTH_MAX ((1 << 23) - 1)
396#define PRECISION_MAX ((1 << 15) - 1)
397
398static noinline_for_stack
399char *number(char *buf, char *end, unsigned long long num,
400 struct printf_spec spec)
401{
402 /* put_dec requires 2-byte alignment of the buffer. */
403 char tmp[3 * sizeof(num)] __aligned(2);
404 char sign;
405 char locase;
406 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
407 int i;
408 bool is_zero = num == 0LL;
409 int field_width = spec.field_width;
410 int precision = spec.precision;
411
412 BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
413
414 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
415 * produces same digits or (maybe lowercased) letters */
416 locase = (spec.flags & SMALL);
417 if (spec.flags & LEFT)
418 spec.flags &= ~ZEROPAD;
419 sign = 0;
420 if (spec.flags & SIGN) {
421 if ((signed long long)num < 0) {
422 sign = '-';
423 num = -(signed long long)num;
424 field_width--;
425 } else if (spec.flags & PLUS) {
426 sign = '+';
427 field_width--;
428 } else if (spec.flags & SPACE) {
429 sign = ' ';
430 field_width--;
431 }
432 }
433 if (need_pfx) {
434 if (spec.base == 16)
435 field_width -= 2;
436 else if (!is_zero)
437 field_width--;
438 }
439
440 /* generate full string in tmp[], in reverse order */
441 i = 0;
442 if (num < spec.base)
443 tmp[i++] = hex_asc_upper[num] | locase;
444 else if (spec.base != 10) { /* 8 or 16 */
445 int mask = spec.base - 1;
446 int shift = 3;
447
448 if (spec.base == 16)
449 shift = 4;
450 do {
451 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
452 num >>= shift;
453 } while (num);
454 } else { /* base 10 */
455 i = put_dec(tmp, num) - tmp;
456 }
457
458 /* printing 100 using %2d gives "100", not "00" */
459 if (i > precision)
460 precision = i;
461 /* leading space padding */
462 field_width -= precision;
463 if (!(spec.flags & (ZEROPAD | LEFT))) {
464 while (--field_width >= 0) {
465 if (buf < end)
466 *buf = ' ';
467 ++buf;
468 }
469 }
470 /* sign */
471 if (sign) {
472 if (buf < end)
473 *buf = sign;
474 ++buf;
475 }
476 /* "0x" / "0" prefix */
477 if (need_pfx) {
478 if (spec.base == 16 || !is_zero) {
479 if (buf < end)
480 *buf = '0';
481 ++buf;
482 }
483 if (spec.base == 16) {
484 if (buf < end)
485 *buf = ('X' | locase);
486 ++buf;
487 }
488 }
489 /* zero or space padding */
490 if (!(spec.flags & LEFT)) {
491 char c = ' ' + (spec.flags & ZEROPAD);
492 BUILD_BUG_ON(' ' + ZEROPAD != '0');
493 while (--field_width >= 0) {
494 if (buf < end)
495 *buf = c;
496 ++buf;
497 }
498 }
499 /* hmm even more zero padding? */
500 while (i <= --precision) {
501 if (buf < end)
502 *buf = '0';
503 ++buf;
504 }
505 /* actual digits of result */
506 while (--i >= 0) {
507 if (buf < end)
508 *buf = tmp[i];
509 ++buf;
510 }
511 /* trailing space padding */
512 while (--field_width >= 0) {
513 if (buf < end)
514 *buf = ' ';
515 ++buf;
516 }
517
518 return buf;
519}
520
521static noinline_for_stack
522char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
523{
524 struct printf_spec spec;
525
526 spec.type = FORMAT_TYPE_PTR;
527 spec.field_width = 2 + 2 * size; /* 0x + hex */
528 spec.flags = SPECIAL | SMALL | ZEROPAD;
529 spec.base = 16;
530 spec.precision = -1;
531
532 return number(buf, end, num, spec);
533}
534
535static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
536{
537 size_t size;
538 if (buf >= end) /* nowhere to put anything */
539 return;
540 size = end - buf;
541 if (size <= spaces) {
542 memset(buf, ' ', size);
543 return;
544 }
545 if (len) {
546 if (len > size - spaces)
547 len = size - spaces;
548 memmove(buf + spaces, buf, len);
549 }
550 memset(buf, ' ', spaces);
551}
552
553/*
554 * Handle field width padding for a string.
555 * @buf: current buffer position
556 * @n: length of string
557 * @end: end of output buffer
558 * @spec: for field width and flags
559 * Returns: new buffer position after padding.
560 */
561static noinline_for_stack
562char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
563{
564 unsigned spaces;
565
566 if (likely(n >= spec.field_width))
567 return buf;
568 /* we want to pad the sucker */
569 spaces = spec.field_width - n;
570 if (!(spec.flags & LEFT)) {
571 move_right(buf - n, end, n, spaces);
572 return buf + spaces;
573 }
574 while (spaces--) {
575 if (buf < end)
576 *buf = ' ';
577 ++buf;
578 }
579 return buf;
580}
581
582static noinline_for_stack
583char *string(char *buf, char *end, const char *s, struct printf_spec spec)
584{
585 int len = 0;
586 size_t lim = spec.precision;
587
588 if ((unsigned long)s < PAGE_SIZE)
589 s = "(null)";
590
591 while (lim--) {
592 char c = *s++;
593 if (!c)
594 break;
595 if (buf < end)
596 *buf = c;
597 ++buf;
598 ++len;
599 }
600 return widen_string(buf, len, end, spec);
601}
602
603static noinline_for_stack
604char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
605 const char *fmt)
606{
607 const char *array[4], *s;
608 const struct dentry *p;
609 int depth;
610 int i, n;
611
612 switch (fmt[1]) {
613 case '2': case '3': case '4':
614 depth = fmt[1] - '0';
615 break;
616 default:
617 depth = 1;
618 }
619
620 rcu_read_lock();
621 for (i = 0; i < depth; i++, d = p) {
622 p = ACCESS_ONCE(d->d_parent);
623 array[i] = ACCESS_ONCE(d->d_name.name);
624 if (p == d) {
625 if (i)
626 array[i] = "";
627 i++;
628 break;
629 }
630 }
631 s = array[--i];
632 for (n = 0; n != spec.precision; n++, buf++) {
633 char c = *s++;
634 if (!c) {
635 if (!i)
636 break;
637 c = '/';
638 s = array[--i];
639 }
640 if (buf < end)
641 *buf = c;
642 }
643 rcu_read_unlock();
644 return widen_string(buf, n, end, spec);
645}
646
647#ifdef CONFIG_BLOCK
648static noinline_for_stack
649char *bdev_name(char *buf, char *end, struct block_device *bdev,
650 struct printf_spec spec, const char *fmt)
651{
652 struct gendisk *hd = bdev->bd_disk;
653
654 buf = string(buf, end, hd->disk_name, spec);
655 if (bdev->bd_part->partno) {
656 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
657 if (buf < end)
658 *buf = 'p';
659 buf++;
660 }
661 buf = number(buf, end, bdev->bd_part->partno, spec);
662 }
663 return buf;
664}
665#endif
666
667static noinline_for_stack
668char *symbol_string(char *buf, char *end, void *ptr,
669 struct printf_spec spec, const char *fmt)
670{
671 unsigned long value;
672#ifdef CONFIG_KALLSYMS
673 char sym[KSYM_SYMBOL_LEN];
674#endif
675
676 if (fmt[1] == 'R')
677 ptr = __builtin_extract_return_addr(ptr);
678 value = (unsigned long)ptr;
679
680#ifdef CONFIG_KALLSYMS
681 if (*fmt == 'B')
682 sprint_backtrace(sym, value);
683 else if (*fmt != 'f' && *fmt != 's')
684 sprint_symbol(sym, value);
685 else
686 sprint_symbol_no_offset(sym, value);
687
688 return string(buf, end, sym, spec);
689#else
690 return special_hex_number(buf, end, value, sizeof(void *));
691#endif
692}
693
694static noinline_for_stack
695char *resource_string(char *buf, char *end, struct resource *res,
696 struct printf_spec spec, const char *fmt)
697{
698#ifndef IO_RSRC_PRINTK_SIZE
699#define IO_RSRC_PRINTK_SIZE 6
700#endif
701
702#ifndef MEM_RSRC_PRINTK_SIZE
703#define MEM_RSRC_PRINTK_SIZE 10
704#endif
705 static const struct printf_spec io_spec = {
706 .base = 16,
707 .field_width = IO_RSRC_PRINTK_SIZE,
708 .precision = -1,
709 .flags = SPECIAL | SMALL | ZEROPAD,
710 };
711 static const struct printf_spec mem_spec = {
712 .base = 16,
713 .field_width = MEM_RSRC_PRINTK_SIZE,
714 .precision = -1,
715 .flags = SPECIAL | SMALL | ZEROPAD,
716 };
717 static const struct printf_spec bus_spec = {
718 .base = 16,
719 .field_width = 2,
720 .precision = -1,
721 .flags = SMALL | ZEROPAD,
722 };
723 static const struct printf_spec dec_spec = {
724 .base = 10,
725 .precision = -1,
726 .flags = 0,
727 };
728 static const struct printf_spec str_spec = {
729 .field_width = -1,
730 .precision = 10,
731 .flags = LEFT,
732 };
733 static const struct printf_spec flag_spec = {
734 .base = 16,
735 .precision = -1,
736 .flags = SPECIAL | SMALL,
737 };
738
739 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
740 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
741#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
742#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
743#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
744#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
745 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
746 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
747
748 char *p = sym, *pend = sym + sizeof(sym);
749 int decode = (fmt[0] == 'R') ? 1 : 0;
750 const struct printf_spec *specp;
751
752 *p++ = '[';
753 if (res->flags & IORESOURCE_IO) {
754 p = string(p, pend, "io ", str_spec);
755 specp = &io_spec;
756 } else if (res->flags & IORESOURCE_MEM) {
757 p = string(p, pend, "mem ", str_spec);
758 specp = &mem_spec;
759 } else if (res->flags & IORESOURCE_IRQ) {
760 p = string(p, pend, "irq ", str_spec);
761 specp = &dec_spec;
762 } else if (res->flags & IORESOURCE_DMA) {
763 p = string(p, pend, "dma ", str_spec);
764 specp = &dec_spec;
765 } else if (res->flags & IORESOURCE_BUS) {
766 p = string(p, pend, "bus ", str_spec);
767 specp = &bus_spec;
768 } else {
769 p = string(p, pend, "??? ", str_spec);
770 specp = &mem_spec;
771 decode = 0;
772 }
773 if (decode && res->flags & IORESOURCE_UNSET) {
774 p = string(p, pend, "size ", str_spec);
775 p = number(p, pend, resource_size(res), *specp);
776 } else {
777 p = number(p, pend, res->start, *specp);
778 if (res->start != res->end) {
779 *p++ = '-';
780 p = number(p, pend, res->end, *specp);
781 }
782 }
783 if (decode) {
784 if (res->flags & IORESOURCE_MEM_64)
785 p = string(p, pend, " 64bit", str_spec);
786 if (res->flags & IORESOURCE_PREFETCH)
787 p = string(p, pend, " pref", str_spec);
788 if (res->flags & IORESOURCE_WINDOW)
789 p = string(p, pend, " window", str_spec);
790 if (res->flags & IORESOURCE_DISABLED)
791 p = string(p, pend, " disabled", str_spec);
792 } else {
793 p = string(p, pend, " flags ", str_spec);
794 p = number(p, pend, res->flags, flag_spec);
795 }
796 *p++ = ']';
797 *p = '\0';
798
799 return string(buf, end, sym, spec);
800}
801
802static noinline_for_stack
803char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
804 const char *fmt)
805{
806 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
807 negative value, fallback to the default */
808 char separator;
809
810 if (spec.field_width == 0)
811 /* nothing to print */
812 return buf;
813
814 if (ZERO_OR_NULL_PTR(addr))
815 /* NULL pointer */
816 return string(buf, end, NULL, spec);
817
818 switch (fmt[1]) {
819 case 'C':
820 separator = ':';
821 break;
822 case 'D':
823 separator = '-';
824 break;
825 case 'N':
826 separator = 0;
827 break;
828 default:
829 separator = ' ';
830 break;
831 }
832
833 if (spec.field_width > 0)
834 len = min_t(int, spec.field_width, 64);
835
836 for (i = 0; i < len; ++i) {
837 if (buf < end)
838 *buf = hex_asc_hi(addr[i]);
839 ++buf;
840 if (buf < end)
841 *buf = hex_asc_lo(addr[i]);
842 ++buf;
843
844 if (separator && i != len - 1) {
845 if (buf < end)
846 *buf = separator;
847 ++buf;
848 }
849 }
850
851 return buf;
852}
853
854static noinline_for_stack
855char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
856 struct printf_spec spec, const char *fmt)
857{
858 const int CHUNKSZ = 32;
859 int nr_bits = max_t(int, spec.field_width, 0);
860 int i, chunksz;
861 bool first = true;
862
863 /* reused to print numbers */
864 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
865
866 chunksz = nr_bits & (CHUNKSZ - 1);
867 if (chunksz == 0)
868 chunksz = CHUNKSZ;
869
870 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
871 for (; i >= 0; i -= CHUNKSZ) {
872 u32 chunkmask, val;
873 int word, bit;
874
875 chunkmask = ((1ULL << chunksz) - 1);
876 word = i / BITS_PER_LONG;
877 bit = i % BITS_PER_LONG;
878 val = (bitmap[word] >> bit) & chunkmask;
879
880 if (!first) {
881 if (buf < end)
882 *buf = ',';
883 buf++;
884 }
885 first = false;
886
887 spec.field_width = DIV_ROUND_UP(chunksz, 4);
888 buf = number(buf, end, val, spec);
889
890 chunksz = CHUNKSZ;
891 }
892 return buf;
893}
894
895static noinline_for_stack
896char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
897 struct printf_spec spec, const char *fmt)
898{
899 int nr_bits = max_t(int, spec.field_width, 0);
900 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
901 int cur, rbot, rtop;
902 bool first = true;
903
904 /* reused to print numbers */
905 spec = (struct printf_spec){ .base = 10 };
906
907 rbot = cur = find_first_bit(bitmap, nr_bits);
908 while (cur < nr_bits) {
909 rtop = cur;
910 cur = find_next_bit(bitmap, nr_bits, cur + 1);
911 if (cur < nr_bits && cur <= rtop + 1)
912 continue;
913
914 if (!first) {
915 if (buf < end)
916 *buf = ',';
917 buf++;
918 }
919 first = false;
920
921 buf = number(buf, end, rbot, spec);
922 if (rbot < rtop) {
923 if (buf < end)
924 *buf = '-';
925 buf++;
926
927 buf = number(buf, end, rtop, spec);
928 }
929
930 rbot = cur;
931 }
932 return buf;
933}
934
935static noinline_for_stack
936char *mac_address_string(char *buf, char *end, u8 *addr,
937 struct printf_spec spec, const char *fmt)
938{
939 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
940 char *p = mac_addr;
941 int i;
942 char separator;
943 bool reversed = false;
944
945 switch (fmt[1]) {
946 case 'F':
947 separator = '-';
948 break;
949
950 case 'R':
951 reversed = true;
952 /* fall through */
953
954 default:
955 separator = ':';
956 break;
957 }
958
959 for (i = 0; i < 6; i++) {
960 if (reversed)
961 p = hex_byte_pack(p, addr[5 - i]);
962 else
963 p = hex_byte_pack(p, addr[i]);
964
965 if (fmt[0] == 'M' && i != 5)
966 *p++ = separator;
967 }
968 *p = '\0';
969
970 return string(buf, end, mac_addr, spec);
971}
972
973static noinline_for_stack
974char *ip4_string(char *p, const u8 *addr, const char *fmt)
975{
976 int i;
977 bool leading_zeros = (fmt[0] == 'i');
978 int index;
979 int step;
980
981 switch (fmt[2]) {
982 case 'h':
983#ifdef __BIG_ENDIAN
984 index = 0;
985 step = 1;
986#else
987 index = 3;
988 step = -1;
989#endif
990 break;
991 case 'l':
992 index = 3;
993 step = -1;
994 break;
995 case 'n':
996 case 'b':
997 default:
998 index = 0;
999 step = 1;
1000 break;
1001 }
1002 for (i = 0; i < 4; i++) {
1003 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1004 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1005 if (leading_zeros) {
1006 if (digits < 3)
1007 *p++ = '0';
1008 if (digits < 2)
1009 *p++ = '0';
1010 }
1011 /* reverse the digits in the quad */
1012 while (digits--)
1013 *p++ = temp[digits];
1014 if (i < 3)
1015 *p++ = '.';
1016 index += step;
1017 }
1018 *p = '\0';
1019
1020 return p;
1021}
1022
1023static noinline_for_stack
1024char *ip6_compressed_string(char *p, const char *addr)
1025{
1026 int i, j, range;
1027 unsigned char zerolength[8];
1028 int longest = 1;
1029 int colonpos = -1;
1030 u16 word;
1031 u8 hi, lo;
1032 bool needcolon = false;
1033 bool useIPv4;
1034 struct in6_addr in6;
1035
1036 memcpy(&in6, addr, sizeof(struct in6_addr));
1037
1038 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1039
1040 memset(zerolength, 0, sizeof(zerolength));
1041
1042 if (useIPv4)
1043 range = 6;
1044 else
1045 range = 8;
1046
1047 /* find position of longest 0 run */
1048 for (i = 0; i < range; i++) {
1049 for (j = i; j < range; j++) {
1050 if (in6.s6_addr16[j] != 0)
1051 break;
1052 zerolength[i]++;
1053 }
1054 }
1055 for (i = 0; i < range; i++) {
1056 if (zerolength[i] > longest) {
1057 longest = zerolength[i];
1058 colonpos = i;
1059 }
1060 }
1061 if (longest == 1) /* don't compress a single 0 */
1062 colonpos = -1;
1063
1064 /* emit address */
1065 for (i = 0; i < range; i++) {
1066 if (i == colonpos) {
1067 if (needcolon || i == 0)
1068 *p++ = ':';
1069 *p++ = ':';
1070 needcolon = false;
1071 i += longest - 1;
1072 continue;
1073 }
1074 if (needcolon) {
1075 *p++ = ':';
1076 needcolon = false;
1077 }
1078 /* hex u16 without leading 0s */
1079 word = ntohs(in6.s6_addr16[i]);
1080 hi = word >> 8;
1081 lo = word & 0xff;
1082 if (hi) {
1083 if (hi > 0x0f)
1084 p = hex_byte_pack(p, hi);
1085 else
1086 *p++ = hex_asc_lo(hi);
1087 p = hex_byte_pack(p, lo);
1088 }
1089 else if (lo > 0x0f)
1090 p = hex_byte_pack(p, lo);
1091 else
1092 *p++ = hex_asc_lo(lo);
1093 needcolon = true;
1094 }
1095
1096 if (useIPv4) {
1097 if (needcolon)
1098 *p++ = ':';
1099 p = ip4_string(p, &in6.s6_addr[12], "I4");
1100 }
1101 *p = '\0';
1102
1103 return p;
1104}
1105
1106static noinline_for_stack
1107char *ip6_string(char *p, const char *addr, const char *fmt)
1108{
1109 int i;
1110
1111 for (i = 0; i < 8; i++) {
1112 p = hex_byte_pack(p, *addr++);
1113 p = hex_byte_pack(p, *addr++);
1114 if (fmt[0] == 'I' && i != 7)
1115 *p++ = ':';
1116 }
1117 *p = '\0';
1118
1119 return p;
1120}
1121
1122static noinline_for_stack
1123char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1124 struct printf_spec spec, const char *fmt)
1125{
1126 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1127
1128 if (fmt[0] == 'I' && fmt[2] == 'c')
1129 ip6_compressed_string(ip6_addr, addr);
1130 else
1131 ip6_string(ip6_addr, addr, fmt);
1132
1133 return string(buf, end, ip6_addr, spec);
1134}
1135
1136static noinline_for_stack
1137char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1138 struct printf_spec spec, const char *fmt)
1139{
1140 char ip4_addr[sizeof("255.255.255.255")];
1141
1142 ip4_string(ip4_addr, addr, fmt);
1143
1144 return string(buf, end, ip4_addr, spec);
1145}
1146
1147static noinline_for_stack
1148char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1149 struct printf_spec spec, const char *fmt)
1150{
1151 bool have_p = false, have_s = false, have_f = false, have_c = false;
1152 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1153 sizeof(":12345") + sizeof("/123456789") +
1154 sizeof("%1234567890")];
1155 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1156 const u8 *addr = (const u8 *) &sa->sin6_addr;
1157 char fmt6[2] = { fmt[0], '6' };
1158 u8 off = 0;
1159
1160 fmt++;
1161 while (isalpha(*++fmt)) {
1162 switch (*fmt) {
1163 case 'p':
1164 have_p = true;
1165 break;
1166 case 'f':
1167 have_f = true;
1168 break;
1169 case 's':
1170 have_s = true;
1171 break;
1172 case 'c':
1173 have_c = true;
1174 break;
1175 }
1176 }
1177
1178 if (have_p || have_s || have_f) {
1179 *p = '[';
1180 off = 1;
1181 }
1182
1183 if (fmt6[0] == 'I' && have_c)
1184 p = ip6_compressed_string(ip6_addr + off, addr);
1185 else
1186 p = ip6_string(ip6_addr + off, addr, fmt6);
1187
1188 if (have_p || have_s || have_f)
1189 *p++ = ']';
1190
1191 if (have_p) {
1192 *p++ = ':';
1193 p = number(p, pend, ntohs(sa->sin6_port), spec);
1194 }
1195 if (have_f) {
1196 *p++ = '/';
1197 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1198 IPV6_FLOWINFO_MASK), spec);
1199 }
1200 if (have_s) {
1201 *p++ = '%';
1202 p = number(p, pend, sa->sin6_scope_id, spec);
1203 }
1204 *p = '\0';
1205
1206 return string(buf, end, ip6_addr, spec);
1207}
1208
1209static noinline_for_stack
1210char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1211 struct printf_spec spec, const char *fmt)
1212{
1213 bool have_p = false;
1214 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1215 char *pend = ip4_addr + sizeof(ip4_addr);
1216 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1217 char fmt4[3] = { fmt[0], '4', 0 };
1218
1219 fmt++;
1220 while (isalpha(*++fmt)) {
1221 switch (*fmt) {
1222 case 'p':
1223 have_p = true;
1224 break;
1225 case 'h':
1226 case 'l':
1227 case 'n':
1228 case 'b':
1229 fmt4[2] = *fmt;
1230 break;
1231 }
1232 }
1233
1234 p = ip4_string(ip4_addr, addr, fmt4);
1235 if (have_p) {
1236 *p++ = ':';
1237 p = number(p, pend, ntohs(sa->sin_port), spec);
1238 }
1239 *p = '\0';
1240
1241 return string(buf, end, ip4_addr, spec);
1242}
1243
1244static noinline_for_stack
1245char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1246 const char *fmt)
1247{
1248 bool found = true;
1249 int count = 1;
1250 unsigned int flags = 0;
1251 int len;
1252
1253 if (spec.field_width == 0)
1254 return buf; /* nothing to print */
1255
1256 if (ZERO_OR_NULL_PTR(addr))
1257 return string(buf, end, NULL, spec); /* NULL pointer */
1258
1259
1260 do {
1261 switch (fmt[count++]) {
1262 case 'a':
1263 flags |= ESCAPE_ANY;
1264 break;
1265 case 'c':
1266 flags |= ESCAPE_SPECIAL;
1267 break;
1268 case 'h':
1269 flags |= ESCAPE_HEX;
1270 break;
1271 case 'n':
1272 flags |= ESCAPE_NULL;
1273 break;
1274 case 'o':
1275 flags |= ESCAPE_OCTAL;
1276 break;
1277 case 'p':
1278 flags |= ESCAPE_NP;
1279 break;
1280 case 's':
1281 flags |= ESCAPE_SPACE;
1282 break;
1283 default:
1284 found = false;
1285 break;
1286 }
1287 } while (found);
1288
1289 if (!flags)
1290 flags = ESCAPE_ANY_NP;
1291
1292 len = spec.field_width < 0 ? 1 : spec.field_width;
1293
1294 /*
1295 * string_escape_mem() writes as many characters as it can to
1296 * the given buffer, and returns the total size of the output
1297 * had the buffer been big enough.
1298 */
1299 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1300
1301 return buf;
1302}
1303
1304static noinline_for_stack
1305char *uuid_string(char *buf, char *end, const u8 *addr,
1306 struct printf_spec spec, const char *fmt)
1307{
1308 char uuid[UUID_STRING_LEN + 1];
1309 char *p = uuid;
1310 int i;
1311 const u8 *index = uuid_be_index;
1312 bool uc = false;
1313
1314 switch (*(++fmt)) {
1315 case 'L':
1316 uc = true; /* fall-through */
1317 case 'l':
1318 index = uuid_le_index;
1319 break;
1320 case 'B':
1321 uc = true;
1322 break;
1323 }
1324
1325 for (i = 0; i < 16; i++) {
1326 if (uc)
1327 p = hex_byte_pack_upper(p, addr[index[i]]);
1328 else
1329 p = hex_byte_pack(p, addr[index[i]]);
1330 switch (i) {
1331 case 3:
1332 case 5:
1333 case 7:
1334 case 9:
1335 *p++ = '-';
1336 break;
1337 }
1338 }
1339
1340 *p = 0;
1341
1342 return string(buf, end, uuid, spec);
1343}
1344
1345static noinline_for_stack
1346char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1347{
1348 unsigned long long num;
1349 int size;
1350
1351 switch (fmt[1]) {
1352 case 'F':
1353 num = *(const netdev_features_t *)addr;
1354 size = sizeof(netdev_features_t);
1355 break;
1356 default:
1357 num = (unsigned long)addr;
1358 size = sizeof(unsigned long);
1359 break;
1360 }
1361
1362 return special_hex_number(buf, end, num, size);
1363}
1364
1365static noinline_for_stack
1366char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1367{
1368 unsigned long long num;
1369 int size;
1370
1371 switch (fmt[1]) {
1372 case 'd':
1373 num = *(const dma_addr_t *)addr;
1374 size = sizeof(dma_addr_t);
1375 break;
1376 case 'p':
1377 default:
1378 num = *(const phys_addr_t *)addr;
1379 size = sizeof(phys_addr_t);
1380 break;
1381 }
1382
1383 return special_hex_number(buf, end, num, size);
1384}
1385
1386static noinline_for_stack
1387char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1388 const char *fmt)
1389{
1390 if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1391 return string(buf, end, NULL, spec);
1392
1393 switch (fmt[1]) {
1394 case 'r':
1395 return number(buf, end, clk_get_rate(clk), spec);
1396
1397 case 'n':
1398 default:
1399#ifdef CONFIG_COMMON_CLK
1400 return string(buf, end, __clk_get_name(clk), spec);
1401#else
1402 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1403#endif
1404 }
1405}
1406
1407static
1408char *format_flags(char *buf, char *end, unsigned long flags,
1409 const struct trace_print_flags *names)
1410{
1411 unsigned long mask;
1412 const struct printf_spec strspec = {
1413 .field_width = -1,
1414 .precision = -1,
1415 };
1416 const struct printf_spec numspec = {
1417 .flags = SPECIAL|SMALL,
1418 .field_width = -1,
1419 .precision = -1,
1420 .base = 16,
1421 };
1422
1423 for ( ; flags && names->name; names++) {
1424 mask = names->mask;
1425 if ((flags & mask) != mask)
1426 continue;
1427
1428 buf = string(buf, end, names->name, strspec);
1429
1430 flags &= ~mask;
1431 if (flags) {
1432 if (buf < end)
1433 *buf = '|';
1434 buf++;
1435 }
1436 }
1437
1438 if (flags)
1439 buf = number(buf, end, flags, numspec);
1440
1441 return buf;
1442}
1443
1444static noinline_for_stack
1445char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1446{
1447 unsigned long flags;
1448 const struct trace_print_flags *names;
1449
1450 switch (fmt[1]) {
1451 case 'p':
1452 flags = *(unsigned long *)flags_ptr;
1453 /* Remove zone id */
1454 flags &= (1UL << NR_PAGEFLAGS) - 1;
1455 names = pageflag_names;
1456 break;
1457 case 'v':
1458 flags = *(unsigned long *)flags_ptr;
1459 names = vmaflag_names;
1460 break;
1461 case 'g':
1462 flags = *(gfp_t *)flags_ptr;
1463 names = gfpflag_names;
1464 break;
1465 default:
1466 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1467 return buf;
1468 }
1469
1470 return format_flags(buf, end, flags, names);
1471}
1472
1473int kptr_restrict __read_mostly;
1474
1475/*
1476 * Show a '%p' thing. A kernel extension is that the '%p' is followed
1477 * by an extra set of alphanumeric characters that are extended format
1478 * specifiers.
1479 *
1480 * Right now we handle:
1481 *
1482 * - 'F' For symbolic function descriptor pointers with offset
1483 * - 'f' For simple symbolic function names without offset
1484 * - 'S' For symbolic direct pointers with offset
1485 * - 's' For symbolic direct pointers without offset
1486 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1487 * - 'B' For backtraced symbolic direct pointers with offset
1488 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1489 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1490 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1491 * width which must be explicitly specified either as part of the
1492 * format string '%32b[l]' or through '%*b[l]', [l] selects
1493 * range-list format instead of hex format
1494 * - 'M' For a 6-byte MAC address, it prints the address in the
1495 * usual colon-separated hex notation
1496 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1497 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1498 * with a dash-separated hex notation
1499 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1500 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1501 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1502 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
1503 * [S][pfs]
1504 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1505 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1506 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1507 * IPv6 omits the colons (01020304...0f)
1508 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1509 * [S][pfs]
1510 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1511 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1512 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1513 * - 'I[6S]c' for IPv6 addresses printed as specified by
1514 * http://tools.ietf.org/html/rfc5952
1515 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1516 * of the following flags (see string_escape_mem() for the
1517 * details):
1518 * a - ESCAPE_ANY
1519 * c - ESCAPE_SPECIAL
1520 * h - ESCAPE_HEX
1521 * n - ESCAPE_NULL
1522 * o - ESCAPE_OCTAL
1523 * p - ESCAPE_NP
1524 * s - ESCAPE_SPACE
1525 * By default ESCAPE_ANY_NP is used.
1526 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1527 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1528 * Options for %pU are:
1529 * b big endian lower case hex (default)
1530 * B big endian UPPER case hex
1531 * l little endian lower case hex
1532 * L little endian UPPER case hex
1533 * big endian output byte order is:
1534 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1535 * little endian output byte order is:
1536 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1537 * - 'V' For a struct va_format which contains a format string * and va_list *,
1538 * call vsnprintf(->format, *->va_list).
1539 * Implements a "recursive vsnprintf".
1540 * Do not use this feature without some mechanism to verify the
1541 * correctness of the format string and va_list arguments.
1542 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1543 * - 'NF' For a netdev_features_t
1544 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1545 * a certain separator (' ' by default):
1546 * C colon
1547 * D dash
1548 * N no separator
1549 * The maximum supported length is 64 bytes of the input. Consider
1550 * to use print_hex_dump() for the larger input.
1551 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1552 * (default assumed to be phys_addr_t, passed by reference)
1553 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1554 * - 'D[234]' Same as 'd' but for a struct file
1555 * - 'g' For block_device name (gendisk + partition number)
1556 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1557 * (legacy clock framework) of the clock
1558 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1559 * (legacy clock framework) of the clock
1560 * - 'Cr' For a clock, it prints the current rate of the clock
1561 * - 'G' For flags to be printed as a collection of symbolic strings that would
1562 * construct the specific value. Supported flags given by option:
1563 * p page flags (see struct page) given as pointer to unsigned long
1564 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1565 * v vma flags (VM_*) given as pointer to unsigned long
1566 *
1567 * ** Please update also Documentation/printk-formats.txt when making changes **
1568 *
1569 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1570 * function pointers are really function descriptors, which contain a
1571 * pointer to the real address.
1572 */
1573static noinline_for_stack
1574char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1575 struct printf_spec spec)
1576{
1577 const int default_width = 2 * sizeof(void *);
1578
1579 if (!ptr && *fmt != 'K') {
1580 /*
1581 * Print (null) with the same width as a pointer so it makes
1582 * tabular output look nice.
1583 */
1584 if (spec.field_width == -1)
1585 spec.field_width = default_width;
1586 return string(buf, end, "(null)", spec);
1587 }
1588
1589 switch (*fmt) {
1590 case 'F':
1591 case 'f':
1592 ptr = dereference_function_descriptor(ptr);
1593 /* Fallthrough */
1594 case 'S':
1595 case 's':
1596 case 'B':
1597 return symbol_string(buf, end, ptr, spec, fmt);
1598 case 'R':
1599 case 'r':
1600 return resource_string(buf, end, ptr, spec, fmt);
1601 case 'h':
1602 return hex_string(buf, end, ptr, spec, fmt);
1603 case 'b':
1604 switch (fmt[1]) {
1605 case 'l':
1606 return bitmap_list_string(buf, end, ptr, spec, fmt);
1607 default:
1608 return bitmap_string(buf, end, ptr, spec, fmt);
1609 }
1610 case 'M': /* Colon separated: 00:01:02:03:04:05 */
1611 case 'm': /* Contiguous: 000102030405 */
1612 /* [mM]F (FDDI) */
1613 /* [mM]R (Reverse order; Bluetooth) */
1614 return mac_address_string(buf, end, ptr, spec, fmt);
1615 case 'I': /* Formatted IP supported
1616 * 4: 1.2.3.4
1617 * 6: 0001:0203:...:0708
1618 * 6c: 1::708 or 1::1.2.3.4
1619 */
1620 case 'i': /* Contiguous:
1621 * 4: 001.002.003.004
1622 * 6: 000102...0f
1623 */
1624 switch (fmt[1]) {
1625 case '6':
1626 return ip6_addr_string(buf, end, ptr, spec, fmt);
1627 case '4':
1628 return ip4_addr_string(buf, end, ptr, spec, fmt);
1629 case 'S': {
1630 const union {
1631 struct sockaddr raw;
1632 struct sockaddr_in v4;
1633 struct sockaddr_in6 v6;
1634 } *sa = ptr;
1635
1636 switch (sa->raw.sa_family) {
1637 case AF_INET:
1638 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1639 case AF_INET6:
1640 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1641 default:
1642 return string(buf, end, "(invalid address)", spec);
1643 }}
1644 }
1645 break;
1646 case 'E':
1647 return escaped_string(buf, end, ptr, spec, fmt);
1648 case 'U':
1649 return uuid_string(buf, end, ptr, spec, fmt);
1650 case 'V':
1651 {
1652 va_list va;
1653
1654 va_copy(va, *((struct va_format *)ptr)->va);
1655 buf += vsnprintf(buf, end > buf ? end - buf : 0,
1656 ((struct va_format *)ptr)->fmt, va);
1657 va_end(va);
1658 return buf;
1659 }
1660 case 'K':
1661 switch (kptr_restrict) {
1662 case 0:
1663 /* Always print %pK values */
1664 break;
1665 case 1: {
1666 const struct cred *cred;
1667
1668 /*
1669 * kptr_restrict==1 cannot be used in IRQ context
1670 * because its test for CAP_SYSLOG would be meaningless.
1671 */
1672 if (in_irq() || in_serving_softirq() || in_nmi()) {
1673 if (spec.field_width == -1)
1674 spec.field_width = default_width;
1675 return string(buf, end, "pK-error", spec);
1676 }
1677
1678 /*
1679 * Only print the real pointer value if the current
1680 * process has CAP_SYSLOG and is running with the
1681 * same credentials it started with. This is because
1682 * access to files is checked at open() time, but %pK
1683 * checks permission at read() time. We don't want to
1684 * leak pointer values if a binary opens a file using
1685 * %pK and then elevates privileges before reading it.
1686 */
1687 cred = current_cred();
1688 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1689 !uid_eq(cred->euid, cred->uid) ||
1690 !gid_eq(cred->egid, cred->gid))
1691 ptr = NULL;
1692 break;
1693 }
1694 case 2:
1695 default:
1696 /* Always print 0's for %pK */
1697 ptr = NULL;
1698 break;
1699 }
1700 break;
1701
1702 case 'N':
1703 return netdev_bits(buf, end, ptr, fmt);
1704 case 'a':
1705 return address_val(buf, end, ptr, fmt);
1706 case 'd':
1707 return dentry_name(buf, end, ptr, spec, fmt);
1708 case 'C':
1709 return clock(buf, end, ptr, spec, fmt);
1710 case 'D':
1711 return dentry_name(buf, end,
1712 ((const struct file *)ptr)->f_path.dentry,
1713 spec, fmt);
1714#ifdef CONFIG_BLOCK
1715 case 'g':
1716 return bdev_name(buf, end, ptr, spec, fmt);
1717#endif
1718
1719 case 'G':
1720 return flags_string(buf, end, ptr, fmt);
1721 }
1722 spec.flags |= SMALL;
1723 if (spec.field_width == -1) {
1724 spec.field_width = default_width;
1725 spec.flags |= ZEROPAD;
1726 }
1727 spec.base = 16;
1728
1729 return number(buf, end, (unsigned long) ptr, spec);
1730}
1731
1732/*
1733 * Helper function to decode printf style format.
1734 * Each call decode a token from the format and return the
1735 * number of characters read (or likely the delta where it wants
1736 * to go on the next call).
1737 * The decoded token is returned through the parameters
1738 *
1739 * 'h', 'l', or 'L' for integer fields
1740 * 'z' support added 23/7/1999 S.H.
1741 * 'z' changed to 'Z' --davidm 1/25/99
1742 * 't' added for ptrdiff_t
1743 *
1744 * @fmt: the format string
1745 * @type of the token returned
1746 * @flags: various flags such as +, -, # tokens..
1747 * @field_width: overwritten width
1748 * @base: base of the number (octal, hex, ...)
1749 * @precision: precision of a number
1750 * @qualifier: qualifier of a number (long, size_t, ...)
1751 */
1752static noinline_for_stack
1753int format_decode(const char *fmt, struct printf_spec *spec)
1754{
1755 const char *start = fmt;
1756 char qualifier;
1757
1758 /* we finished early by reading the field width */
1759 if (spec->type == FORMAT_TYPE_WIDTH) {
1760 if (spec->field_width < 0) {
1761 spec->field_width = -spec->field_width;
1762 spec->flags |= LEFT;
1763 }
1764 spec->type = FORMAT_TYPE_NONE;
1765 goto precision;
1766 }
1767
1768 /* we finished early by reading the precision */
1769 if (spec->type == FORMAT_TYPE_PRECISION) {
1770 if (spec->precision < 0)
1771 spec->precision = 0;
1772
1773 spec->type = FORMAT_TYPE_NONE;
1774 goto qualifier;
1775 }
1776
1777 /* By default */
1778 spec->type = FORMAT_TYPE_NONE;
1779
1780 for (; *fmt ; ++fmt) {
1781 if (*fmt == '%')
1782 break;
1783 }
1784
1785 /* Return the current non-format string */
1786 if (fmt != start || !*fmt)
1787 return fmt - start;
1788
1789 /* Process flags */
1790 spec->flags = 0;
1791
1792 while (1) { /* this also skips first '%' */
1793 bool found = true;
1794
1795 ++fmt;
1796
1797 switch (*fmt) {
1798 case '-': spec->flags |= LEFT; break;
1799 case '+': spec->flags |= PLUS; break;
1800 case ' ': spec->flags |= SPACE; break;
1801 case '#': spec->flags |= SPECIAL; break;
1802 case '0': spec->flags |= ZEROPAD; break;
1803 default: found = false;
1804 }
1805
1806 if (!found)
1807 break;
1808 }
1809
1810 /* get field width */
1811 spec->field_width = -1;
1812
1813 if (isdigit(*fmt))
1814 spec->field_width = skip_atoi(&fmt);
1815 else if (*fmt == '*') {
1816 /* it's the next argument */
1817 spec->type = FORMAT_TYPE_WIDTH;
1818 return ++fmt - start;
1819 }
1820
1821precision:
1822 /* get the precision */
1823 spec->precision = -1;
1824 if (*fmt == '.') {
1825 ++fmt;
1826 if (isdigit(*fmt)) {
1827 spec->precision = skip_atoi(&fmt);
1828 if (spec->precision < 0)
1829 spec->precision = 0;
1830 } else if (*fmt == '*') {
1831 /* it's the next argument */
1832 spec->type = FORMAT_TYPE_PRECISION;
1833 return ++fmt - start;
1834 }
1835 }
1836
1837qualifier:
1838 /* get the conversion qualifier */
1839 qualifier = 0;
1840 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1841 _tolower(*fmt) == 'z' || *fmt == 't') {
1842 qualifier = *fmt++;
1843 if (unlikely(qualifier == *fmt)) {
1844 if (qualifier == 'l') {
1845 qualifier = 'L';
1846 ++fmt;
1847 } else if (qualifier == 'h') {
1848 qualifier = 'H';
1849 ++fmt;
1850 }
1851 }
1852 }
1853
1854 /* default base */
1855 spec->base = 10;
1856 switch (*fmt) {
1857 case 'c':
1858 spec->type = FORMAT_TYPE_CHAR;
1859 return ++fmt - start;
1860
1861 case 's':
1862 spec->type = FORMAT_TYPE_STR;
1863 return ++fmt - start;
1864
1865 case 'p':
1866 spec->type = FORMAT_TYPE_PTR;
1867 return ++fmt - start;
1868
1869 case '%':
1870 spec->type = FORMAT_TYPE_PERCENT_CHAR;
1871 return ++fmt - start;
1872
1873 /* integer number formats - set up the flags and "break" */
1874 case 'o':
1875 spec->base = 8;
1876 break;
1877
1878 case 'x':
1879 spec->flags |= SMALL;
1880
1881 case 'X':
1882 spec->base = 16;
1883 break;
1884
1885 case 'd':
1886 case 'i':
1887 spec->flags |= SIGN;
1888 case 'u':
1889 break;
1890
1891 case 'n':
1892 /*
1893 * Since %n poses a greater security risk than
1894 * utility, treat it as any other invalid or
1895 * unsupported format specifier.
1896 */
1897 /* Fall-through */
1898
1899 default:
1900 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
1901 spec->type = FORMAT_TYPE_INVALID;
1902 return fmt - start;
1903 }
1904
1905 if (qualifier == 'L')
1906 spec->type = FORMAT_TYPE_LONG_LONG;
1907 else if (qualifier == 'l') {
1908 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
1909 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
1910 } else if (_tolower(qualifier) == 'z') {
1911 spec->type = FORMAT_TYPE_SIZE_T;
1912 } else if (qualifier == 't') {
1913 spec->type = FORMAT_TYPE_PTRDIFF;
1914 } else if (qualifier == 'H') {
1915 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
1916 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
1917 } else if (qualifier == 'h') {
1918 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
1919 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
1920 } else {
1921 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
1922 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
1923 }
1924
1925 return ++fmt - start;
1926}
1927
1928static void
1929set_field_width(struct printf_spec *spec, int width)
1930{
1931 spec->field_width = width;
1932 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
1933 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
1934 }
1935}
1936
1937static void
1938set_precision(struct printf_spec *spec, int prec)
1939{
1940 spec->precision = prec;
1941 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
1942 spec->precision = clamp(prec, 0, PRECISION_MAX);
1943 }
1944}
1945
1946/**
1947 * vsnprintf - Format a string and place it in a buffer
1948 * @buf: The buffer to place the result into
1949 * @size: The size of the buffer, including the trailing null space
1950 * @fmt: The format string to use
1951 * @args: Arguments for the format string
1952 *
1953 * This function generally follows C99 vsnprintf, but has some
1954 * extensions and a few limitations:
1955 *
1956 * %n is unsupported
1957 * %p* is handled by pointer()
1958 *
1959 * See pointer() or Documentation/printk-formats.txt for more
1960 * extensive description.
1961 *
1962 * ** Please update the documentation in both places when making changes **
1963 *
1964 * The return value is the number of characters which would
1965 * be generated for the given input, excluding the trailing
1966 * '\0', as per ISO C99. If you want to have the exact
1967 * number of characters written into @buf as return value
1968 * (not including the trailing '\0'), use vscnprintf(). If the
1969 * return is greater than or equal to @size, the resulting
1970 * string is truncated.
1971 *
1972 * If you're not already dealing with a va_list consider using snprintf().
1973 */
1974int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1975{
1976 unsigned long long num;
1977 char *str, *end;
1978 struct printf_spec spec = {0};
1979
1980 /* Reject out-of-range values early. Large positive sizes are
1981 used for unknown buffer sizes. */
1982 if (WARN_ON_ONCE(size > INT_MAX))
1983 return 0;
1984
1985 str = buf;
1986 end = buf + size;
1987
1988 /* Make sure end is always >= buf */
1989 if (end < buf) {
1990 end = ((void *)-1);
1991 size = end - buf;
1992 }
1993
1994 while (*fmt) {
1995 const char *old_fmt = fmt;
1996 int read = format_decode(fmt, &spec);
1997
1998 fmt += read;
1999
2000 switch (spec.type) {
2001 case FORMAT_TYPE_NONE: {
2002 int copy = read;
2003 if (str < end) {
2004 if (copy > end - str)
2005 copy = end - str;
2006 memcpy(str, old_fmt, copy);
2007 }
2008 str += read;
2009 break;
2010 }
2011
2012 case FORMAT_TYPE_WIDTH:
2013 set_field_width(&spec, va_arg(args, int));
2014 break;
2015
2016 case FORMAT_TYPE_PRECISION:
2017 set_precision(&spec, va_arg(args, int));
2018 break;
2019
2020 case FORMAT_TYPE_CHAR: {
2021 char c;
2022
2023 if (!(spec.flags & LEFT)) {
2024 while (--spec.field_width > 0) {
2025 if (str < end)
2026 *str = ' ';
2027 ++str;
2028
2029 }
2030 }
2031 c = (unsigned char) va_arg(args, int);
2032 if (str < end)
2033 *str = c;
2034 ++str;
2035 while (--spec.field_width > 0) {
2036 if (str < end)
2037 *str = ' ';
2038 ++str;
2039 }
2040 break;
2041 }
2042
2043 case FORMAT_TYPE_STR:
2044 str = string(str, end, va_arg(args, char *), spec);
2045 break;
2046
2047 case FORMAT_TYPE_PTR:
2048 str = pointer(fmt, str, end, va_arg(args, void *),
2049 spec);
2050 while (isalnum(*fmt))
2051 fmt++;
2052 break;
2053
2054 case FORMAT_TYPE_PERCENT_CHAR:
2055 if (str < end)
2056 *str = '%';
2057 ++str;
2058 break;
2059
2060 case FORMAT_TYPE_INVALID:
2061 /*
2062 * Presumably the arguments passed gcc's type
2063 * checking, but there is no safe or sane way
2064 * for us to continue parsing the format and
2065 * fetching from the va_list; the remaining
2066 * specifiers and arguments would be out of
2067 * sync.
2068 */
2069 goto out;
2070
2071 default:
2072 switch (spec.type) {
2073 case FORMAT_TYPE_LONG_LONG:
2074 num = va_arg(args, long long);
2075 break;
2076 case FORMAT_TYPE_ULONG:
2077 num = va_arg(args, unsigned long);
2078 break;
2079 case FORMAT_TYPE_LONG:
2080 num = va_arg(args, long);
2081 break;
2082 case FORMAT_TYPE_SIZE_T:
2083 if (spec.flags & SIGN)
2084 num = va_arg(args, ssize_t);
2085 else
2086 num = va_arg(args, size_t);
2087 break;
2088 case FORMAT_TYPE_PTRDIFF:
2089 num = va_arg(args, ptrdiff_t);
2090 break;
2091 case FORMAT_TYPE_UBYTE:
2092 num = (unsigned char) va_arg(args, int);
2093 break;
2094 case FORMAT_TYPE_BYTE:
2095 num = (signed char) va_arg(args, int);
2096 break;
2097 case FORMAT_TYPE_USHORT:
2098 num = (unsigned short) va_arg(args, int);
2099 break;
2100 case FORMAT_TYPE_SHORT:
2101 num = (short) va_arg(args, int);
2102 break;
2103 case FORMAT_TYPE_INT:
2104 num = (int) va_arg(args, int);
2105 break;
2106 default:
2107 num = va_arg(args, unsigned int);
2108 }
2109
2110 str = number(str, end, num, spec);
2111 }
2112 }
2113
2114out:
2115 if (size > 0) {
2116 if (str < end)
2117 *str = '\0';
2118 else
2119 end[-1] = '\0';
2120 }
2121
2122 /* the trailing null byte doesn't count towards the total */
2123 return str-buf;
2124
2125}
2126EXPORT_SYMBOL(vsnprintf);
2127
2128/**
2129 * vscnprintf - Format a string and place it in a buffer
2130 * @buf: The buffer to place the result into
2131 * @size: The size of the buffer, including the trailing null space
2132 * @fmt: The format string to use
2133 * @args: Arguments for the format string
2134 *
2135 * The return value is the number of characters which have been written into
2136 * the @buf not including the trailing '\0'. If @size is == 0 the function
2137 * returns 0.
2138 *
2139 * If you're not already dealing with a va_list consider using scnprintf().
2140 *
2141 * See the vsnprintf() documentation for format string extensions over C99.
2142 */
2143int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2144{
2145 int i;
2146
2147 i = vsnprintf(buf, size, fmt, args);
2148
2149 if (likely(i < size))
2150 return i;
2151 if (size != 0)
2152 return size - 1;
2153 return 0;
2154}
2155EXPORT_SYMBOL(vscnprintf);
2156
2157/**
2158 * snprintf - Format a string and place it in a buffer
2159 * @buf: The buffer to place the result into
2160 * @size: The size of the buffer, including the trailing null space
2161 * @fmt: The format string to use
2162 * @...: Arguments for the format string
2163 *
2164 * The return value is the number of characters which would be
2165 * generated for the given input, excluding the trailing null,
2166 * as per ISO C99. If the return is greater than or equal to
2167 * @size, the resulting string is truncated.
2168 *
2169 * See the vsnprintf() documentation for format string extensions over C99.
2170 */
2171int snprintf(char *buf, size_t size, const char *fmt, ...)
2172{
2173 va_list args;
2174 int i;
2175
2176 va_start(args, fmt);
2177 i = vsnprintf(buf, size, fmt, args);
2178 va_end(args);
2179
2180 return i;
2181}
2182EXPORT_SYMBOL(snprintf);
2183
2184/**
2185 * scnprintf - Format a string and place it in a buffer
2186 * @buf: The buffer to place the result into
2187 * @size: The size of the buffer, including the trailing null space
2188 * @fmt: The format string to use
2189 * @...: Arguments for the format string
2190 *
2191 * The return value is the number of characters written into @buf not including
2192 * the trailing '\0'. If @size is == 0 the function returns 0.
2193 */
2194
2195int scnprintf(char *buf, size_t size, const char *fmt, ...)
2196{
2197 va_list args;
2198 int i;
2199
2200 va_start(args, fmt);
2201 i = vscnprintf(buf, size, fmt, args);
2202 va_end(args);
2203
2204 return i;
2205}
2206EXPORT_SYMBOL(scnprintf);
2207
2208/**
2209 * vsprintf - Format a string and place it in a buffer
2210 * @buf: The buffer to place the result into
2211 * @fmt: The format string to use
2212 * @args: Arguments for the format string
2213 *
2214 * The function returns the number of characters written
2215 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2216 * buffer overflows.
2217 *
2218 * If you're not already dealing with a va_list consider using sprintf().
2219 *
2220 * See the vsnprintf() documentation for format string extensions over C99.
2221 */
2222int vsprintf(char *buf, const char *fmt, va_list args)
2223{
2224 return vsnprintf(buf, INT_MAX, fmt, args);
2225}
2226EXPORT_SYMBOL(vsprintf);
2227
2228/**
2229 * sprintf - Format a string and place it in a buffer
2230 * @buf: The buffer to place the result into
2231 * @fmt: The format string to use
2232 * @...: Arguments for the format string
2233 *
2234 * The function returns the number of characters written
2235 * into @buf. Use snprintf() or scnprintf() in order to avoid
2236 * buffer overflows.
2237 *
2238 * See the vsnprintf() documentation for format string extensions over C99.
2239 */
2240int sprintf(char *buf, const char *fmt, ...)
2241{
2242 va_list args;
2243 int i;
2244
2245 va_start(args, fmt);
2246 i = vsnprintf(buf, INT_MAX, fmt, args);
2247 va_end(args);
2248
2249 return i;
2250}
2251EXPORT_SYMBOL(sprintf);
2252
2253#ifdef CONFIG_BINARY_PRINTF
2254/*
2255 * bprintf service:
2256 * vbin_printf() - VA arguments to binary data
2257 * bstr_printf() - Binary data to text string
2258 */
2259
2260/**
2261 * vbin_printf - Parse a format string and place args' binary value in a buffer
2262 * @bin_buf: The buffer to place args' binary value
2263 * @size: The size of the buffer(by words(32bits), not characters)
2264 * @fmt: The format string to use
2265 * @args: Arguments for the format string
2266 *
2267 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2268 * is skipped.
2269 *
2270 * The return value is the number of words(32bits) which would be generated for
2271 * the given input.
2272 *
2273 * NOTE:
2274 * If the return value is greater than @size, the resulting bin_buf is NOT
2275 * valid for bstr_printf().
2276 */
2277int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2278{
2279 struct printf_spec spec = {0};
2280 char *str, *end;
2281
2282 str = (char *)bin_buf;
2283 end = (char *)(bin_buf + size);
2284
2285#define save_arg(type) \
2286do { \
2287 if (sizeof(type) == 8) { \
2288 unsigned long long value; \
2289 str = PTR_ALIGN(str, sizeof(u32)); \
2290 value = va_arg(args, unsigned long long); \
2291 if (str + sizeof(type) <= end) { \
2292 *(u32 *)str = *(u32 *)&value; \
2293 *(u32 *)(str + 4) = *((u32 *)&value + 1); \
2294 } \
2295 } else { \
2296 unsigned long value; \
2297 str = PTR_ALIGN(str, sizeof(type)); \
2298 value = va_arg(args, int); \
2299 if (str + sizeof(type) <= end) \
2300 *(typeof(type) *)str = (type)value; \
2301 } \
2302 str += sizeof(type); \
2303} while (0)
2304
2305 while (*fmt) {
2306 int read = format_decode(fmt, &spec);
2307
2308 fmt += read;
2309
2310 switch (spec.type) {
2311 case FORMAT_TYPE_NONE:
2312 case FORMAT_TYPE_PERCENT_CHAR:
2313 break;
2314 case FORMAT_TYPE_INVALID:
2315 goto out;
2316
2317 case FORMAT_TYPE_WIDTH:
2318 case FORMAT_TYPE_PRECISION:
2319 save_arg(int);
2320 break;
2321
2322 case FORMAT_TYPE_CHAR:
2323 save_arg(char);
2324 break;
2325
2326 case FORMAT_TYPE_STR: {
2327 const char *save_str = va_arg(args, char *);
2328 size_t len;
2329
2330 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2331 || (unsigned long)save_str < PAGE_SIZE)
2332 save_str = "(null)";
2333 len = strlen(save_str) + 1;
2334 if (str + len < end)
2335 memcpy(str, save_str, len);
2336 str += len;
2337 break;
2338 }
2339
2340 case FORMAT_TYPE_PTR:
2341 save_arg(void *);
2342 /* skip all alphanumeric pointer suffixes */
2343 while (isalnum(*fmt))
2344 fmt++;
2345 break;
2346
2347 default:
2348 switch (spec.type) {
2349
2350 case FORMAT_TYPE_LONG_LONG:
2351 save_arg(long long);
2352 break;
2353 case FORMAT_TYPE_ULONG:
2354 case FORMAT_TYPE_LONG:
2355 save_arg(unsigned long);
2356 break;
2357 case FORMAT_TYPE_SIZE_T:
2358 save_arg(size_t);
2359 break;
2360 case FORMAT_TYPE_PTRDIFF:
2361 save_arg(ptrdiff_t);
2362 break;
2363 case FORMAT_TYPE_UBYTE:
2364 case FORMAT_TYPE_BYTE:
2365 save_arg(char);
2366 break;
2367 case FORMAT_TYPE_USHORT:
2368 case FORMAT_TYPE_SHORT:
2369 save_arg(short);
2370 break;
2371 default:
2372 save_arg(int);
2373 }
2374 }
2375 }
2376
2377out:
2378 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2379#undef save_arg
2380}
2381EXPORT_SYMBOL_GPL(vbin_printf);
2382
2383/**
2384 * bstr_printf - Format a string from binary arguments and place it in a buffer
2385 * @buf: The buffer to place the result into
2386 * @size: The size of the buffer, including the trailing null space
2387 * @fmt: The format string to use
2388 * @bin_buf: Binary arguments for the format string
2389 *
2390 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2391 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2392 * a binary buffer that generated by vbin_printf.
2393 *
2394 * The format follows C99 vsnprintf, but has some extensions:
2395 * see vsnprintf comment for details.
2396 *
2397 * The return value is the number of characters which would
2398 * be generated for the given input, excluding the trailing
2399 * '\0', as per ISO C99. If you want to have the exact
2400 * number of characters written into @buf as return value
2401 * (not including the trailing '\0'), use vscnprintf(). If the
2402 * return is greater than or equal to @size, the resulting
2403 * string is truncated.
2404 */
2405int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2406{
2407 struct printf_spec spec = {0};
2408 char *str, *end;
2409 const char *args = (const char *)bin_buf;
2410
2411 if (WARN_ON_ONCE(size > INT_MAX))
2412 return 0;
2413
2414 str = buf;
2415 end = buf + size;
2416
2417#define get_arg(type) \
2418({ \
2419 typeof(type) value; \
2420 if (sizeof(type) == 8) { \
2421 args = PTR_ALIGN(args, sizeof(u32)); \
2422 *(u32 *)&value = *(u32 *)args; \
2423 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2424 } else { \
2425 args = PTR_ALIGN(args, sizeof(type)); \
2426 value = *(typeof(type) *)args; \
2427 } \
2428 args += sizeof(type); \
2429 value; \
2430})
2431
2432 /* Make sure end is always >= buf */
2433 if (end < buf) {
2434 end = ((void *)-1);
2435 size = end - buf;
2436 }
2437
2438 while (*fmt) {
2439 const char *old_fmt = fmt;
2440 int read = format_decode(fmt, &spec);
2441
2442 fmt += read;
2443
2444 switch (spec.type) {
2445 case FORMAT_TYPE_NONE: {
2446 int copy = read;
2447 if (str < end) {
2448 if (copy > end - str)
2449 copy = end - str;
2450 memcpy(str, old_fmt, copy);
2451 }
2452 str += read;
2453 break;
2454 }
2455
2456 case FORMAT_TYPE_WIDTH:
2457 set_field_width(&spec, get_arg(int));
2458 break;
2459
2460 case FORMAT_TYPE_PRECISION:
2461 set_precision(&spec, get_arg(int));
2462 break;
2463
2464 case FORMAT_TYPE_CHAR: {
2465 char c;
2466
2467 if (!(spec.flags & LEFT)) {
2468 while (--spec.field_width > 0) {
2469 if (str < end)
2470 *str = ' ';
2471 ++str;
2472 }
2473 }
2474 c = (unsigned char) get_arg(char);
2475 if (str < end)
2476 *str = c;
2477 ++str;
2478 while (--spec.field_width > 0) {
2479 if (str < end)
2480 *str = ' ';
2481 ++str;
2482 }
2483 break;
2484 }
2485
2486 case FORMAT_TYPE_STR: {
2487 const char *str_arg = args;
2488 args += strlen(str_arg) + 1;
2489 str = string(str, end, (char *)str_arg, spec);
2490 break;
2491 }
2492
2493 case FORMAT_TYPE_PTR:
2494 str = pointer(fmt, str, end, get_arg(void *), spec);
2495 while (isalnum(*fmt))
2496 fmt++;
2497 break;
2498
2499 case FORMAT_TYPE_PERCENT_CHAR:
2500 if (str < end)
2501 *str = '%';
2502 ++str;
2503 break;
2504
2505 case FORMAT_TYPE_INVALID:
2506 goto out;
2507
2508 default: {
2509 unsigned long long num;
2510
2511 switch (spec.type) {
2512
2513 case FORMAT_TYPE_LONG_LONG:
2514 num = get_arg(long long);
2515 break;
2516 case FORMAT_TYPE_ULONG:
2517 case FORMAT_TYPE_LONG:
2518 num = get_arg(unsigned long);
2519 break;
2520 case FORMAT_TYPE_SIZE_T:
2521 num = get_arg(size_t);
2522 break;
2523 case FORMAT_TYPE_PTRDIFF:
2524 num = get_arg(ptrdiff_t);
2525 break;
2526 case FORMAT_TYPE_UBYTE:
2527 num = get_arg(unsigned char);
2528 break;
2529 case FORMAT_TYPE_BYTE:
2530 num = get_arg(signed char);
2531 break;
2532 case FORMAT_TYPE_USHORT:
2533 num = get_arg(unsigned short);
2534 break;
2535 case FORMAT_TYPE_SHORT:
2536 num = get_arg(short);
2537 break;
2538 case FORMAT_TYPE_UINT:
2539 num = get_arg(unsigned int);
2540 break;
2541 default:
2542 num = get_arg(int);
2543 }
2544
2545 str = number(str, end, num, spec);
2546 } /* default: */
2547 } /* switch(spec.type) */
2548 } /* while(*fmt) */
2549
2550out:
2551 if (size > 0) {
2552 if (str < end)
2553 *str = '\0';
2554 else
2555 end[-1] = '\0';
2556 }
2557
2558#undef get_arg
2559
2560 /* the trailing null byte doesn't count towards the total */
2561 return str - buf;
2562}
2563EXPORT_SYMBOL_GPL(bstr_printf);
2564
2565/**
2566 * bprintf - Parse a format string and place args' binary value in a buffer
2567 * @bin_buf: The buffer to place args' binary value
2568 * @size: The size of the buffer(by words(32bits), not characters)
2569 * @fmt: The format string to use
2570 * @...: Arguments for the format string
2571 *
2572 * The function returns the number of words(u32) written
2573 * into @bin_buf.
2574 */
2575int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2576{
2577 va_list args;
2578 int ret;
2579
2580 va_start(args, fmt);
2581 ret = vbin_printf(bin_buf, size, fmt, args);
2582 va_end(args);
2583
2584 return ret;
2585}
2586EXPORT_SYMBOL_GPL(bprintf);
2587
2588#endif /* CONFIG_BINARY_PRINTF */
2589
2590/**
2591 * vsscanf - Unformat a buffer into a list of arguments
2592 * @buf: input buffer
2593 * @fmt: format of buffer
2594 * @args: arguments
2595 */
2596int vsscanf(const char *buf, const char *fmt, va_list args)
2597{
2598 const char *str = buf;
2599 char *next;
2600 char digit;
2601 int num = 0;
2602 u8 qualifier;
2603 unsigned int base;
2604 union {
2605 long long s;
2606 unsigned long long u;
2607 } val;
2608 s16 field_width;
2609 bool is_sign;
2610
2611 while (*fmt) {
2612 /* skip any white space in format */
2613 /* white space in format matchs any amount of
2614 * white space, including none, in the input.
2615 */
2616 if (isspace(*fmt)) {
2617 fmt = skip_spaces(++fmt);
2618 str = skip_spaces(str);
2619 }
2620
2621 /* anything that is not a conversion must match exactly */
2622 if (*fmt != '%' && *fmt) {
2623 if (*fmt++ != *str++)
2624 break;
2625 continue;
2626 }
2627
2628 if (!*fmt)
2629 break;
2630 ++fmt;
2631
2632 /* skip this conversion.
2633 * advance both strings to next white space
2634 */
2635 if (*fmt == '*') {
2636 if (!*str)
2637 break;
2638 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2639 /* '%*[' not yet supported, invalid format */
2640 if (*fmt == '[')
2641 return num;
2642 fmt++;
2643 }
2644 while (!isspace(*str) && *str)
2645 str++;
2646 continue;
2647 }
2648
2649 /* get field width */
2650 field_width = -1;
2651 if (isdigit(*fmt)) {
2652 field_width = skip_atoi(&fmt);
2653 if (field_width <= 0)
2654 break;
2655 }
2656
2657 /* get conversion qualifier */
2658 qualifier = -1;
2659 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2660 _tolower(*fmt) == 'z') {
2661 qualifier = *fmt++;
2662 if (unlikely(qualifier == *fmt)) {
2663 if (qualifier == 'h') {
2664 qualifier = 'H';
2665 fmt++;
2666 } else if (qualifier == 'l') {
2667 qualifier = 'L';
2668 fmt++;
2669 }
2670 }
2671 }
2672
2673 if (!*fmt)
2674 break;
2675
2676 if (*fmt == 'n') {
2677 /* return number of characters read so far */
2678 *va_arg(args, int *) = str - buf;
2679 ++fmt;
2680 continue;
2681 }
2682
2683 if (!*str)
2684 break;
2685
2686 base = 10;
2687 is_sign = false;
2688
2689 switch (*fmt++) {
2690 case 'c':
2691 {
2692 char *s = (char *)va_arg(args, char*);
2693 if (field_width == -1)
2694 field_width = 1;
2695 do {
2696 *s++ = *str++;
2697 } while (--field_width > 0 && *str);
2698 num++;
2699 }
2700 continue;
2701 case 's':
2702 {
2703 char *s = (char *)va_arg(args, char *);
2704 if (field_width == -1)
2705 field_width = SHRT_MAX;
2706 /* first, skip leading white space in buffer */
2707 str = skip_spaces(str);
2708
2709 /* now copy until next white space */
2710 while (*str && !isspace(*str) && field_width--)
2711 *s++ = *str++;
2712 *s = '\0';
2713 num++;
2714 }
2715 continue;
2716 /*
2717 * Warning: This implementation of the '[' conversion specifier
2718 * deviates from its glibc counterpart in the following ways:
2719 * (1) It does NOT support ranges i.e. '-' is NOT a special
2720 * character
2721 * (2) It cannot match the closing bracket ']' itself
2722 * (3) A field width is required
2723 * (4) '%*[' (discard matching input) is currently not supported
2724 *
2725 * Example usage:
2726 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
2727 * buf1, buf2, buf3);
2728 * if (ret < 3)
2729 * // etc..
2730 */
2731 case '[':
2732 {
2733 char *s = (char *)va_arg(args, char *);
2734 DECLARE_BITMAP(set, 256) = {0};
2735 unsigned int len = 0;
2736 bool negate = (*fmt == '^');
2737
2738 /* field width is required */
2739 if (field_width == -1)
2740 return num;
2741
2742 if (negate)
2743 ++fmt;
2744
2745 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
2746 set_bit((u8)*fmt, set);
2747
2748 /* no ']' or no character set found */
2749 if (!*fmt || !len)
2750 return num;
2751 ++fmt;
2752
2753 if (negate) {
2754 bitmap_complement(set, set, 256);
2755 /* exclude null '\0' byte */
2756 clear_bit(0, set);
2757 }
2758
2759 /* match must be non-empty */
2760 if (!test_bit((u8)*str, set))
2761 return num;
2762
2763 while (test_bit((u8)*str, set) && field_width--)
2764 *s++ = *str++;
2765 *s = '\0';
2766 ++num;
2767 }
2768 continue;
2769 case 'o':
2770 base = 8;
2771 break;
2772 case 'x':
2773 case 'X':
2774 base = 16;
2775 break;
2776 case 'i':
2777 base = 0;
2778 case 'd':
2779 is_sign = true;
2780 case 'u':
2781 break;
2782 case '%':
2783 /* looking for '%' in str */
2784 if (*str++ != '%')
2785 return num;
2786 continue;
2787 default:
2788 /* invalid format; stop here */
2789 return num;
2790 }
2791
2792 /* have some sort of integer conversion.
2793 * first, skip white space in buffer.
2794 */
2795 str = skip_spaces(str);
2796
2797 digit = *str;
2798 if (is_sign && digit == '-')
2799 digit = *(str + 1);
2800
2801 if (!digit
2802 || (base == 16 && !isxdigit(digit))
2803 || (base == 10 && !isdigit(digit))
2804 || (base == 8 && (!isdigit(digit) || digit > '7'))
2805 || (base == 0 && !isdigit(digit)))
2806 break;
2807
2808 if (is_sign)
2809 val.s = qualifier != 'L' ?
2810 simple_strtol(str, &next, base) :
2811 simple_strtoll(str, &next, base);
2812 else
2813 val.u = qualifier != 'L' ?
2814 simple_strtoul(str, &next, base) :
2815 simple_strtoull(str, &next, base);
2816
2817 if (field_width > 0 && next - str > field_width) {
2818 if (base == 0)
2819 _parse_integer_fixup_radix(str, &base);
2820 while (next - str > field_width) {
2821 if (is_sign)
2822 val.s = div_s64(val.s, base);
2823 else
2824 val.u = div_u64(val.u, base);
2825 --next;
2826 }
2827 }
2828
2829 switch (qualifier) {
2830 case 'H': /* that's 'hh' in format */
2831 if (is_sign)
2832 *va_arg(args, signed char *) = val.s;
2833 else
2834 *va_arg(args, unsigned char *) = val.u;
2835 break;
2836 case 'h':
2837 if (is_sign)
2838 *va_arg(args, short *) = val.s;
2839 else
2840 *va_arg(args, unsigned short *) = val.u;
2841 break;
2842 case 'l':
2843 if (is_sign)
2844 *va_arg(args, long *) = val.s;
2845 else
2846 *va_arg(args, unsigned long *) = val.u;
2847 break;
2848 case 'L':
2849 if (is_sign)
2850 *va_arg(args, long long *) = val.s;
2851 else
2852 *va_arg(args, unsigned long long *) = val.u;
2853 break;
2854 case 'Z':
2855 case 'z':
2856 *va_arg(args, size_t *) = val.u;
2857 break;
2858 default:
2859 if (is_sign)
2860 *va_arg(args, int *) = val.s;
2861 else
2862 *va_arg(args, unsigned int *) = val.u;
2863 break;
2864 }
2865 num++;
2866
2867 if (!next)
2868 break;
2869 str = next;
2870 }
2871
2872 return num;
2873}
2874EXPORT_SYMBOL(vsscanf);
2875
2876/**
2877 * sscanf - Unformat a buffer into a list of arguments
2878 * @buf: input buffer
2879 * @fmt: formatting of buffer
2880 * @...: resulting arguments
2881 */
2882int sscanf(const char *buf, const char *fmt, ...)
2883{
2884 va_list args;
2885 int i;
2886
2887 va_start(args, fmt);
2888 i = vsscanf(buf, fmt, args);
2889 va_end(args);
2890
2891 return i;
2892}
2893EXPORT_SYMBOL(sscanf);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/lib/vsprintf.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
8/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
9/*
10 * Wirzenius wrote this portably, Torvalds fucked it up :-)
11 */
12
13/*
14 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
15 * - changed to provide snprintf and vsnprintf functions
16 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
17 * - scnprintf and vscnprintf
18 */
19
20#include <stdarg.h>
21#include <linux/build_bug.h>
22#include <linux/clk.h>
23#include <linux/clk-provider.h>
24#include <linux/module.h> /* for KSYM_SYMBOL_LEN */
25#include <linux/types.h>
26#include <linux/string.h>
27#include <linux/ctype.h>
28#include <linux/kernel.h>
29#include <linux/kallsyms.h>
30#include <linux/math64.h>
31#include <linux/uaccess.h>
32#include <linux/ioport.h>
33#include <linux/dcache.h>
34#include <linux/cred.h>
35#include <linux/rtc.h>
36#include <linux/uuid.h>
37#include <linux/of.h>
38#include <net/addrconf.h>
39#include <linux/siphash.h>
40#include <linux/compiler.h>
41#ifdef CONFIG_BLOCK
42#include <linux/blkdev.h>
43#endif
44
45#include "../mm/internal.h" /* For the trace_print_flags arrays */
46
47#include <asm/page.h> /* for PAGE_SIZE */
48#include <asm/byteorder.h> /* cpu_to_le16 */
49
50#include <linux/string_helpers.h>
51#include "kstrtox.h"
52
53/**
54 * simple_strtoull - convert a string to an unsigned long long
55 * @cp: The start of the string
56 * @endp: A pointer to the end of the parsed string will be placed here
57 * @base: The number base to use
58 *
59 * This function is obsolete. Please use kstrtoull instead.
60 */
61unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
62{
63 unsigned long long result;
64 unsigned int rv;
65
66 cp = _parse_integer_fixup_radix(cp, &base);
67 rv = _parse_integer(cp, base, &result);
68 /* FIXME */
69 cp += (rv & ~KSTRTOX_OVERFLOW);
70
71 if (endp)
72 *endp = (char *)cp;
73
74 return result;
75}
76EXPORT_SYMBOL(simple_strtoull);
77
78/**
79 * simple_strtoul - convert a string to an unsigned long
80 * @cp: The start of the string
81 * @endp: A pointer to the end of the parsed string will be placed here
82 * @base: The number base to use
83 *
84 * This function is obsolete. Please use kstrtoul instead.
85 */
86unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
87{
88 return simple_strtoull(cp, endp, base);
89}
90EXPORT_SYMBOL(simple_strtoul);
91
92/**
93 * simple_strtol - convert a string to a signed long
94 * @cp: The start of the string
95 * @endp: A pointer to the end of the parsed string will be placed here
96 * @base: The number base to use
97 *
98 * This function is obsolete. Please use kstrtol instead.
99 */
100long simple_strtol(const char *cp, char **endp, unsigned int base)
101{
102 if (*cp == '-')
103 return -simple_strtoul(cp + 1, endp, base);
104
105 return simple_strtoul(cp, endp, base);
106}
107EXPORT_SYMBOL(simple_strtol);
108
109/**
110 * simple_strtoll - convert a string to a signed long long
111 * @cp: The start of the string
112 * @endp: A pointer to the end of the parsed string will be placed here
113 * @base: The number base to use
114 *
115 * This function is obsolete. Please use kstrtoll instead.
116 */
117long long simple_strtoll(const char *cp, char **endp, unsigned int base)
118{
119 if (*cp == '-')
120 return -simple_strtoull(cp + 1, endp, base);
121
122 return simple_strtoull(cp, endp, base);
123}
124EXPORT_SYMBOL(simple_strtoll);
125
126static noinline_for_stack
127int skip_atoi(const char **s)
128{
129 int i = 0;
130
131 do {
132 i = i*10 + *((*s)++) - '0';
133 } while (isdigit(**s));
134
135 return i;
136}
137
138/*
139 * Decimal conversion is by far the most typical, and is used for
140 * /proc and /sys data. This directly impacts e.g. top performance
141 * with many processes running. We optimize it for speed by emitting
142 * two characters at a time, using a 200 byte lookup table. This
143 * roughly halves the number of multiplications compared to computing
144 * the digits one at a time. Implementation strongly inspired by the
145 * previous version, which in turn used ideas described at
146 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
147 * from the author, Douglas W. Jones).
148 *
149 * It turns out there is precisely one 26 bit fixed-point
150 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
151 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
152 * range happens to be somewhat larger (x <= 1073741898), but that's
153 * irrelevant for our purpose.
154 *
155 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
156 * need a 32x32->64 bit multiply, so we simply use the same constant.
157 *
158 * For dividing a number in the range [100, 10^4-1] by 100, there are
159 * several options. The simplest is (x * 0x147b) >> 19, which is valid
160 * for all x <= 43698.
161 */
162
163static const u16 decpair[100] = {
164#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
165 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
166 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
167 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
168 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
169 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
170 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
171 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
172 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
173 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
174 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
175#undef _
176};
177
178/*
179 * This will print a single '0' even if r == 0, since we would
180 * immediately jump to out_r where two 0s would be written but only
181 * one of them accounted for in buf. This is needed by ip4_string
182 * below. All other callers pass a non-zero value of r.
183*/
184static noinline_for_stack
185char *put_dec_trunc8(char *buf, unsigned r)
186{
187 unsigned q;
188
189 /* 1 <= r < 10^8 */
190 if (r < 100)
191 goto out_r;
192
193 /* 100 <= r < 10^8 */
194 q = (r * (u64)0x28f5c29) >> 32;
195 *((u16 *)buf) = decpair[r - 100*q];
196 buf += 2;
197
198 /* 1 <= q < 10^6 */
199 if (q < 100)
200 goto out_q;
201
202 /* 100 <= q < 10^6 */
203 r = (q * (u64)0x28f5c29) >> 32;
204 *((u16 *)buf) = decpair[q - 100*r];
205 buf += 2;
206
207 /* 1 <= r < 10^4 */
208 if (r < 100)
209 goto out_r;
210
211 /* 100 <= r < 10^4 */
212 q = (r * 0x147b) >> 19;
213 *((u16 *)buf) = decpair[r - 100*q];
214 buf += 2;
215out_q:
216 /* 1 <= q < 100 */
217 r = q;
218out_r:
219 /* 1 <= r < 100 */
220 *((u16 *)buf) = decpair[r];
221 buf += r < 10 ? 1 : 2;
222 return buf;
223}
224
225#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
226static noinline_for_stack
227char *put_dec_full8(char *buf, unsigned r)
228{
229 unsigned q;
230
231 /* 0 <= r < 10^8 */
232 q = (r * (u64)0x28f5c29) >> 32;
233 *((u16 *)buf) = decpair[r - 100*q];
234 buf += 2;
235
236 /* 0 <= q < 10^6 */
237 r = (q * (u64)0x28f5c29) >> 32;
238 *((u16 *)buf) = decpair[q - 100*r];
239 buf += 2;
240
241 /* 0 <= r < 10^4 */
242 q = (r * 0x147b) >> 19;
243 *((u16 *)buf) = decpair[r - 100*q];
244 buf += 2;
245
246 /* 0 <= q < 100 */
247 *((u16 *)buf) = decpair[q];
248 buf += 2;
249 return buf;
250}
251
252static noinline_for_stack
253char *put_dec(char *buf, unsigned long long n)
254{
255 if (n >= 100*1000*1000)
256 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
257 /* 1 <= n <= 1.6e11 */
258 if (n >= 100*1000*1000)
259 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
260 /* 1 <= n < 1e8 */
261 return put_dec_trunc8(buf, n);
262}
263
264#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
265
266static void
267put_dec_full4(char *buf, unsigned r)
268{
269 unsigned q;
270
271 /* 0 <= r < 10^4 */
272 q = (r * 0x147b) >> 19;
273 *((u16 *)buf) = decpair[r - 100*q];
274 buf += 2;
275 /* 0 <= q < 100 */
276 *((u16 *)buf) = decpair[q];
277}
278
279/*
280 * Call put_dec_full4 on x % 10000, return x / 10000.
281 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
282 * holds for all x < 1,128,869,999. The largest value this
283 * helper will ever be asked to convert is 1,125,520,955.
284 * (second call in the put_dec code, assuming n is all-ones).
285 */
286static noinline_for_stack
287unsigned put_dec_helper4(char *buf, unsigned x)
288{
289 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
290
291 put_dec_full4(buf, x - q * 10000);
292 return q;
293}
294
295/* Based on code by Douglas W. Jones found at
296 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
297 * (with permission from the author).
298 * Performs no 64-bit division and hence should be fast on 32-bit machines.
299 */
300static
301char *put_dec(char *buf, unsigned long long n)
302{
303 uint32_t d3, d2, d1, q, h;
304
305 if (n < 100*1000*1000)
306 return put_dec_trunc8(buf, n);
307
308 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
309 h = (n >> 32);
310 d2 = (h ) & 0xffff;
311 d3 = (h >> 16); /* implicit "& 0xffff" */
312
313 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
314 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
315 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
316 q = put_dec_helper4(buf, q);
317
318 q += 7671 * d3 + 9496 * d2 + 6 * d1;
319 q = put_dec_helper4(buf+4, q);
320
321 q += 4749 * d3 + 42 * d2;
322 q = put_dec_helper4(buf+8, q);
323
324 q += 281 * d3;
325 buf += 12;
326 if (q)
327 buf = put_dec_trunc8(buf, q);
328 else while (buf[-1] == '0')
329 --buf;
330
331 return buf;
332}
333
334#endif
335
336/*
337 * Convert passed number to decimal string.
338 * Returns the length of string. On buffer overflow, returns 0.
339 *
340 * If speed is not important, use snprintf(). It's easy to read the code.
341 */
342int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
343{
344 /* put_dec requires 2-byte alignment of the buffer. */
345 char tmp[sizeof(num) * 3] __aligned(2);
346 int idx, len;
347
348 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
349 if (num <= 9) {
350 tmp[0] = '0' + num;
351 len = 1;
352 } else {
353 len = put_dec(tmp, num) - tmp;
354 }
355
356 if (len > size || width > size)
357 return 0;
358
359 if (width > len) {
360 width = width - len;
361 for (idx = 0; idx < width; idx++)
362 buf[idx] = ' ';
363 } else {
364 width = 0;
365 }
366
367 for (idx = 0; idx < len; ++idx)
368 buf[idx + width] = tmp[len - idx - 1];
369
370 return len + width;
371}
372
373#define SIGN 1 /* unsigned/signed, must be 1 */
374#define LEFT 2 /* left justified */
375#define PLUS 4 /* show plus */
376#define SPACE 8 /* space if plus */
377#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
378#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
379#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
380
381enum format_type {
382 FORMAT_TYPE_NONE, /* Just a string part */
383 FORMAT_TYPE_WIDTH,
384 FORMAT_TYPE_PRECISION,
385 FORMAT_TYPE_CHAR,
386 FORMAT_TYPE_STR,
387 FORMAT_TYPE_PTR,
388 FORMAT_TYPE_PERCENT_CHAR,
389 FORMAT_TYPE_INVALID,
390 FORMAT_TYPE_LONG_LONG,
391 FORMAT_TYPE_ULONG,
392 FORMAT_TYPE_LONG,
393 FORMAT_TYPE_UBYTE,
394 FORMAT_TYPE_BYTE,
395 FORMAT_TYPE_USHORT,
396 FORMAT_TYPE_SHORT,
397 FORMAT_TYPE_UINT,
398 FORMAT_TYPE_INT,
399 FORMAT_TYPE_SIZE_T,
400 FORMAT_TYPE_PTRDIFF
401};
402
403struct printf_spec {
404 unsigned int type:8; /* format_type enum */
405 signed int field_width:24; /* width of output field */
406 unsigned int flags:8; /* flags to number() */
407 unsigned int base:8; /* number base, 8, 10 or 16 only */
408 signed int precision:16; /* # of digits/chars */
409} __packed;
410static_assert(sizeof(struct printf_spec) == 8);
411
412#define FIELD_WIDTH_MAX ((1 << 23) - 1)
413#define PRECISION_MAX ((1 << 15) - 1)
414
415static noinline_for_stack
416char *number(char *buf, char *end, unsigned long long num,
417 struct printf_spec spec)
418{
419 /* put_dec requires 2-byte alignment of the buffer. */
420 char tmp[3 * sizeof(num)] __aligned(2);
421 char sign;
422 char locase;
423 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
424 int i;
425 bool is_zero = num == 0LL;
426 int field_width = spec.field_width;
427 int precision = spec.precision;
428
429 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
430 * produces same digits or (maybe lowercased) letters */
431 locase = (spec.flags & SMALL);
432 if (spec.flags & LEFT)
433 spec.flags &= ~ZEROPAD;
434 sign = 0;
435 if (spec.flags & SIGN) {
436 if ((signed long long)num < 0) {
437 sign = '-';
438 num = -(signed long long)num;
439 field_width--;
440 } else if (spec.flags & PLUS) {
441 sign = '+';
442 field_width--;
443 } else if (spec.flags & SPACE) {
444 sign = ' ';
445 field_width--;
446 }
447 }
448 if (need_pfx) {
449 if (spec.base == 16)
450 field_width -= 2;
451 else if (!is_zero)
452 field_width--;
453 }
454
455 /* generate full string in tmp[], in reverse order */
456 i = 0;
457 if (num < spec.base)
458 tmp[i++] = hex_asc_upper[num] | locase;
459 else if (spec.base != 10) { /* 8 or 16 */
460 int mask = spec.base - 1;
461 int shift = 3;
462
463 if (spec.base == 16)
464 shift = 4;
465 do {
466 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
467 num >>= shift;
468 } while (num);
469 } else { /* base 10 */
470 i = put_dec(tmp, num) - tmp;
471 }
472
473 /* printing 100 using %2d gives "100", not "00" */
474 if (i > precision)
475 precision = i;
476 /* leading space padding */
477 field_width -= precision;
478 if (!(spec.flags & (ZEROPAD | LEFT))) {
479 while (--field_width >= 0) {
480 if (buf < end)
481 *buf = ' ';
482 ++buf;
483 }
484 }
485 /* sign */
486 if (sign) {
487 if (buf < end)
488 *buf = sign;
489 ++buf;
490 }
491 /* "0x" / "0" prefix */
492 if (need_pfx) {
493 if (spec.base == 16 || !is_zero) {
494 if (buf < end)
495 *buf = '0';
496 ++buf;
497 }
498 if (spec.base == 16) {
499 if (buf < end)
500 *buf = ('X' | locase);
501 ++buf;
502 }
503 }
504 /* zero or space padding */
505 if (!(spec.flags & LEFT)) {
506 char c = ' ' + (spec.flags & ZEROPAD);
507 BUILD_BUG_ON(' ' + ZEROPAD != '0');
508 while (--field_width >= 0) {
509 if (buf < end)
510 *buf = c;
511 ++buf;
512 }
513 }
514 /* hmm even more zero padding? */
515 while (i <= --precision) {
516 if (buf < end)
517 *buf = '0';
518 ++buf;
519 }
520 /* actual digits of result */
521 while (--i >= 0) {
522 if (buf < end)
523 *buf = tmp[i];
524 ++buf;
525 }
526 /* trailing space padding */
527 while (--field_width >= 0) {
528 if (buf < end)
529 *buf = ' ';
530 ++buf;
531 }
532
533 return buf;
534}
535
536static noinline_for_stack
537char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
538{
539 struct printf_spec spec;
540
541 spec.type = FORMAT_TYPE_PTR;
542 spec.field_width = 2 + 2 * size; /* 0x + hex */
543 spec.flags = SPECIAL | SMALL | ZEROPAD;
544 spec.base = 16;
545 spec.precision = -1;
546
547 return number(buf, end, num, spec);
548}
549
550static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
551{
552 size_t size;
553 if (buf >= end) /* nowhere to put anything */
554 return;
555 size = end - buf;
556 if (size <= spaces) {
557 memset(buf, ' ', size);
558 return;
559 }
560 if (len) {
561 if (len > size - spaces)
562 len = size - spaces;
563 memmove(buf + spaces, buf, len);
564 }
565 memset(buf, ' ', spaces);
566}
567
568/*
569 * Handle field width padding for a string.
570 * @buf: current buffer position
571 * @n: length of string
572 * @end: end of output buffer
573 * @spec: for field width and flags
574 * Returns: new buffer position after padding.
575 */
576static noinline_for_stack
577char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
578{
579 unsigned spaces;
580
581 if (likely(n >= spec.field_width))
582 return buf;
583 /* we want to pad the sucker */
584 spaces = spec.field_width - n;
585 if (!(spec.flags & LEFT)) {
586 move_right(buf - n, end, n, spaces);
587 return buf + spaces;
588 }
589 while (spaces--) {
590 if (buf < end)
591 *buf = ' ';
592 ++buf;
593 }
594 return buf;
595}
596
597/* Handle string from a well known address. */
598static char *string_nocheck(char *buf, char *end, const char *s,
599 struct printf_spec spec)
600{
601 int len = 0;
602 int lim = spec.precision;
603
604 while (lim--) {
605 char c = *s++;
606 if (!c)
607 break;
608 if (buf < end)
609 *buf = c;
610 ++buf;
611 ++len;
612 }
613 return widen_string(buf, len, end, spec);
614}
615
616/* Be careful: error messages must fit into the given buffer. */
617static char *error_string(char *buf, char *end, const char *s,
618 struct printf_spec spec)
619{
620 /*
621 * Hard limit to avoid a completely insane messages. It actually
622 * works pretty well because most error messages are in
623 * the many pointer format modifiers.
624 */
625 if (spec.precision == -1)
626 spec.precision = 2 * sizeof(void *);
627
628 return string_nocheck(buf, end, s, spec);
629}
630
631/*
632 * Do not call any complex external code here. Nested printk()/vsprintf()
633 * might cause infinite loops. Failures might break printk() and would
634 * be hard to debug.
635 */
636static const char *check_pointer_msg(const void *ptr)
637{
638 if (!ptr)
639 return "(null)";
640
641 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
642 return "(efault)";
643
644 return NULL;
645}
646
647static int check_pointer(char **buf, char *end, const void *ptr,
648 struct printf_spec spec)
649{
650 const char *err_msg;
651
652 err_msg = check_pointer_msg(ptr);
653 if (err_msg) {
654 *buf = error_string(*buf, end, err_msg, spec);
655 return -EFAULT;
656 }
657
658 return 0;
659}
660
661static noinline_for_stack
662char *string(char *buf, char *end, const char *s,
663 struct printf_spec spec)
664{
665 if (check_pointer(&buf, end, s, spec))
666 return buf;
667
668 return string_nocheck(buf, end, s, spec);
669}
670
671static char *pointer_string(char *buf, char *end,
672 const void *ptr,
673 struct printf_spec spec)
674{
675 spec.base = 16;
676 spec.flags |= SMALL;
677 if (spec.field_width == -1) {
678 spec.field_width = 2 * sizeof(ptr);
679 spec.flags |= ZEROPAD;
680 }
681
682 return number(buf, end, (unsigned long int)ptr, spec);
683}
684
685/* Make pointers available for printing early in the boot sequence. */
686static int debug_boot_weak_hash __ro_after_init;
687
688static int __init debug_boot_weak_hash_enable(char *str)
689{
690 debug_boot_weak_hash = 1;
691 pr_info("debug_boot_weak_hash enabled\n");
692 return 0;
693}
694early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
695
696static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
697static siphash_key_t ptr_key __read_mostly;
698
699static void enable_ptr_key_workfn(struct work_struct *work)
700{
701 get_random_bytes(&ptr_key, sizeof(ptr_key));
702 /* Needs to run from preemptible context */
703 static_branch_disable(¬_filled_random_ptr_key);
704}
705
706static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
707
708static void fill_random_ptr_key(struct random_ready_callback *unused)
709{
710 /* This may be in an interrupt handler. */
711 queue_work(system_unbound_wq, &enable_ptr_key_work);
712}
713
714static struct random_ready_callback random_ready = {
715 .func = fill_random_ptr_key
716};
717
718static int __init initialize_ptr_random(void)
719{
720 int key_size = sizeof(ptr_key);
721 int ret;
722
723 /* Use hw RNG if available. */
724 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
725 static_branch_disable(¬_filled_random_ptr_key);
726 return 0;
727 }
728
729 ret = add_random_ready_callback(&random_ready);
730 if (!ret) {
731 return 0;
732 } else if (ret == -EALREADY) {
733 /* This is in preemptible context */
734 enable_ptr_key_workfn(&enable_ptr_key_work);
735 return 0;
736 }
737
738 return ret;
739}
740early_initcall(initialize_ptr_random);
741
742/* Maps a pointer to a 32 bit unique identifier. */
743static char *ptr_to_id(char *buf, char *end, const void *ptr,
744 struct printf_spec spec)
745{
746 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
747 unsigned long hashval;
748
749 /* When debugging early boot use non-cryptographically secure hash. */
750 if (unlikely(debug_boot_weak_hash)) {
751 hashval = hash_long((unsigned long)ptr, 32);
752 return pointer_string(buf, end, (const void *)hashval, spec);
753 }
754
755 if (static_branch_unlikely(¬_filled_random_ptr_key)) {
756 spec.field_width = 2 * sizeof(ptr);
757 /* string length must be less than default_width */
758 return error_string(buf, end, str, spec);
759 }
760
761#ifdef CONFIG_64BIT
762 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
763 /*
764 * Mask off the first 32 bits, this makes explicit that we have
765 * modified the address (and 32 bits is plenty for a unique ID).
766 */
767 hashval = hashval & 0xffffffff;
768#else
769 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
770#endif
771 return pointer_string(buf, end, (const void *)hashval, spec);
772}
773
774int kptr_restrict __read_mostly;
775
776static noinline_for_stack
777char *restricted_pointer(char *buf, char *end, const void *ptr,
778 struct printf_spec spec)
779{
780 switch (kptr_restrict) {
781 case 0:
782 /* Handle as %p, hash and do _not_ leak addresses. */
783 return ptr_to_id(buf, end, ptr, spec);
784 case 1: {
785 const struct cred *cred;
786
787 /*
788 * kptr_restrict==1 cannot be used in IRQ context
789 * because its test for CAP_SYSLOG would be meaningless.
790 */
791 if (in_irq() || in_serving_softirq() || in_nmi()) {
792 if (spec.field_width == -1)
793 spec.field_width = 2 * sizeof(ptr);
794 return error_string(buf, end, "pK-error", spec);
795 }
796
797 /*
798 * Only print the real pointer value if the current
799 * process has CAP_SYSLOG and is running with the
800 * same credentials it started with. This is because
801 * access to files is checked at open() time, but %pK
802 * checks permission at read() time. We don't want to
803 * leak pointer values if a binary opens a file using
804 * %pK and then elevates privileges before reading it.
805 */
806 cred = current_cred();
807 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
808 !uid_eq(cred->euid, cred->uid) ||
809 !gid_eq(cred->egid, cred->gid))
810 ptr = NULL;
811 break;
812 }
813 case 2:
814 default:
815 /* Always print 0's for %pK */
816 ptr = NULL;
817 break;
818 }
819
820 return pointer_string(buf, end, ptr, spec);
821}
822
823static noinline_for_stack
824char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
825 const char *fmt)
826{
827 const char *array[4], *s;
828 const struct dentry *p;
829 int depth;
830 int i, n;
831
832 switch (fmt[1]) {
833 case '2': case '3': case '4':
834 depth = fmt[1] - '0';
835 break;
836 default:
837 depth = 1;
838 }
839
840 rcu_read_lock();
841 for (i = 0; i < depth; i++, d = p) {
842 if (check_pointer(&buf, end, d, spec)) {
843 rcu_read_unlock();
844 return buf;
845 }
846
847 p = READ_ONCE(d->d_parent);
848 array[i] = READ_ONCE(d->d_name.name);
849 if (p == d) {
850 if (i)
851 array[i] = "";
852 i++;
853 break;
854 }
855 }
856 s = array[--i];
857 for (n = 0; n != spec.precision; n++, buf++) {
858 char c = *s++;
859 if (!c) {
860 if (!i)
861 break;
862 c = '/';
863 s = array[--i];
864 }
865 if (buf < end)
866 *buf = c;
867 }
868 rcu_read_unlock();
869 return widen_string(buf, n, end, spec);
870}
871
872static noinline_for_stack
873char *file_dentry_name(char *buf, char *end, const struct file *f,
874 struct printf_spec spec, const char *fmt)
875{
876 if (check_pointer(&buf, end, f, spec))
877 return buf;
878
879 return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
880}
881#ifdef CONFIG_BLOCK
882static noinline_for_stack
883char *bdev_name(char *buf, char *end, struct block_device *bdev,
884 struct printf_spec spec, const char *fmt)
885{
886 struct gendisk *hd;
887
888 if (check_pointer(&buf, end, bdev, spec))
889 return buf;
890
891 hd = bdev->bd_disk;
892 buf = string(buf, end, hd->disk_name, spec);
893 if (bdev->bd_part->partno) {
894 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
895 if (buf < end)
896 *buf = 'p';
897 buf++;
898 }
899 buf = number(buf, end, bdev->bd_part->partno, spec);
900 }
901 return buf;
902}
903#endif
904
905static noinline_for_stack
906char *symbol_string(char *buf, char *end, void *ptr,
907 struct printf_spec spec, const char *fmt)
908{
909 unsigned long value;
910#ifdef CONFIG_KALLSYMS
911 char sym[KSYM_SYMBOL_LEN];
912#endif
913
914 if (fmt[1] == 'R')
915 ptr = __builtin_extract_return_addr(ptr);
916 value = (unsigned long)ptr;
917
918#ifdef CONFIG_KALLSYMS
919 if (*fmt == 'B')
920 sprint_backtrace(sym, value);
921 else if (*fmt != 'f' && *fmt != 's')
922 sprint_symbol(sym, value);
923 else
924 sprint_symbol_no_offset(sym, value);
925
926 return string_nocheck(buf, end, sym, spec);
927#else
928 return special_hex_number(buf, end, value, sizeof(void *));
929#endif
930}
931
932static const struct printf_spec default_str_spec = {
933 .field_width = -1,
934 .precision = -1,
935};
936
937static const struct printf_spec default_flag_spec = {
938 .base = 16,
939 .precision = -1,
940 .flags = SPECIAL | SMALL,
941};
942
943static const struct printf_spec default_dec_spec = {
944 .base = 10,
945 .precision = -1,
946};
947
948static const struct printf_spec default_dec02_spec = {
949 .base = 10,
950 .field_width = 2,
951 .precision = -1,
952 .flags = ZEROPAD,
953};
954
955static const struct printf_spec default_dec04_spec = {
956 .base = 10,
957 .field_width = 4,
958 .precision = -1,
959 .flags = ZEROPAD,
960};
961
962static noinline_for_stack
963char *resource_string(char *buf, char *end, struct resource *res,
964 struct printf_spec spec, const char *fmt)
965{
966#ifndef IO_RSRC_PRINTK_SIZE
967#define IO_RSRC_PRINTK_SIZE 6
968#endif
969
970#ifndef MEM_RSRC_PRINTK_SIZE
971#define MEM_RSRC_PRINTK_SIZE 10
972#endif
973 static const struct printf_spec io_spec = {
974 .base = 16,
975 .field_width = IO_RSRC_PRINTK_SIZE,
976 .precision = -1,
977 .flags = SPECIAL | SMALL | ZEROPAD,
978 };
979 static const struct printf_spec mem_spec = {
980 .base = 16,
981 .field_width = MEM_RSRC_PRINTK_SIZE,
982 .precision = -1,
983 .flags = SPECIAL | SMALL | ZEROPAD,
984 };
985 static const struct printf_spec bus_spec = {
986 .base = 16,
987 .field_width = 2,
988 .precision = -1,
989 .flags = SMALL | ZEROPAD,
990 };
991 static const struct printf_spec str_spec = {
992 .field_width = -1,
993 .precision = 10,
994 .flags = LEFT,
995 };
996
997 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
998 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
999#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
1000#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
1001#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
1002#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
1003 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
1004 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
1005
1006 char *p = sym, *pend = sym + sizeof(sym);
1007 int decode = (fmt[0] == 'R') ? 1 : 0;
1008 const struct printf_spec *specp;
1009
1010 if (check_pointer(&buf, end, res, spec))
1011 return buf;
1012
1013 *p++ = '[';
1014 if (res->flags & IORESOURCE_IO) {
1015 p = string_nocheck(p, pend, "io ", str_spec);
1016 specp = &io_spec;
1017 } else if (res->flags & IORESOURCE_MEM) {
1018 p = string_nocheck(p, pend, "mem ", str_spec);
1019 specp = &mem_spec;
1020 } else if (res->flags & IORESOURCE_IRQ) {
1021 p = string_nocheck(p, pend, "irq ", str_spec);
1022 specp = &default_dec_spec;
1023 } else if (res->flags & IORESOURCE_DMA) {
1024 p = string_nocheck(p, pend, "dma ", str_spec);
1025 specp = &default_dec_spec;
1026 } else if (res->flags & IORESOURCE_BUS) {
1027 p = string_nocheck(p, pend, "bus ", str_spec);
1028 specp = &bus_spec;
1029 } else {
1030 p = string_nocheck(p, pend, "??? ", str_spec);
1031 specp = &mem_spec;
1032 decode = 0;
1033 }
1034 if (decode && res->flags & IORESOURCE_UNSET) {
1035 p = string_nocheck(p, pend, "size ", str_spec);
1036 p = number(p, pend, resource_size(res), *specp);
1037 } else {
1038 p = number(p, pend, res->start, *specp);
1039 if (res->start != res->end) {
1040 *p++ = '-';
1041 p = number(p, pend, res->end, *specp);
1042 }
1043 }
1044 if (decode) {
1045 if (res->flags & IORESOURCE_MEM_64)
1046 p = string_nocheck(p, pend, " 64bit", str_spec);
1047 if (res->flags & IORESOURCE_PREFETCH)
1048 p = string_nocheck(p, pend, " pref", str_spec);
1049 if (res->flags & IORESOURCE_WINDOW)
1050 p = string_nocheck(p, pend, " window", str_spec);
1051 if (res->flags & IORESOURCE_DISABLED)
1052 p = string_nocheck(p, pend, " disabled", str_spec);
1053 } else {
1054 p = string_nocheck(p, pend, " flags ", str_spec);
1055 p = number(p, pend, res->flags, default_flag_spec);
1056 }
1057 *p++ = ']';
1058 *p = '\0';
1059
1060 return string_nocheck(buf, end, sym, spec);
1061}
1062
1063static noinline_for_stack
1064char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1065 const char *fmt)
1066{
1067 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
1068 negative value, fallback to the default */
1069 char separator;
1070
1071 if (spec.field_width == 0)
1072 /* nothing to print */
1073 return buf;
1074
1075 if (check_pointer(&buf, end, addr, spec))
1076 return buf;
1077
1078 switch (fmt[1]) {
1079 case 'C':
1080 separator = ':';
1081 break;
1082 case 'D':
1083 separator = '-';
1084 break;
1085 case 'N':
1086 separator = 0;
1087 break;
1088 default:
1089 separator = ' ';
1090 break;
1091 }
1092
1093 if (spec.field_width > 0)
1094 len = min_t(int, spec.field_width, 64);
1095
1096 for (i = 0; i < len; ++i) {
1097 if (buf < end)
1098 *buf = hex_asc_hi(addr[i]);
1099 ++buf;
1100 if (buf < end)
1101 *buf = hex_asc_lo(addr[i]);
1102 ++buf;
1103
1104 if (separator && i != len - 1) {
1105 if (buf < end)
1106 *buf = separator;
1107 ++buf;
1108 }
1109 }
1110
1111 return buf;
1112}
1113
1114static noinline_for_stack
1115char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1116 struct printf_spec spec, const char *fmt)
1117{
1118 const int CHUNKSZ = 32;
1119 int nr_bits = max_t(int, spec.field_width, 0);
1120 int i, chunksz;
1121 bool first = true;
1122
1123 if (check_pointer(&buf, end, bitmap, spec))
1124 return buf;
1125
1126 /* reused to print numbers */
1127 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1128
1129 chunksz = nr_bits & (CHUNKSZ - 1);
1130 if (chunksz == 0)
1131 chunksz = CHUNKSZ;
1132
1133 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1134 for (; i >= 0; i -= CHUNKSZ) {
1135 u32 chunkmask, val;
1136 int word, bit;
1137
1138 chunkmask = ((1ULL << chunksz) - 1);
1139 word = i / BITS_PER_LONG;
1140 bit = i % BITS_PER_LONG;
1141 val = (bitmap[word] >> bit) & chunkmask;
1142
1143 if (!first) {
1144 if (buf < end)
1145 *buf = ',';
1146 buf++;
1147 }
1148 first = false;
1149
1150 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1151 buf = number(buf, end, val, spec);
1152
1153 chunksz = CHUNKSZ;
1154 }
1155 return buf;
1156}
1157
1158static noinline_for_stack
1159char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1160 struct printf_spec spec, const char *fmt)
1161{
1162 int nr_bits = max_t(int, spec.field_width, 0);
1163 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1164 int cur, rbot, rtop;
1165 bool first = true;
1166
1167 if (check_pointer(&buf, end, bitmap, spec))
1168 return buf;
1169
1170 rbot = cur = find_first_bit(bitmap, nr_bits);
1171 while (cur < nr_bits) {
1172 rtop = cur;
1173 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1174 if (cur < nr_bits && cur <= rtop + 1)
1175 continue;
1176
1177 if (!first) {
1178 if (buf < end)
1179 *buf = ',';
1180 buf++;
1181 }
1182 first = false;
1183
1184 buf = number(buf, end, rbot, default_dec_spec);
1185 if (rbot < rtop) {
1186 if (buf < end)
1187 *buf = '-';
1188 buf++;
1189
1190 buf = number(buf, end, rtop, default_dec_spec);
1191 }
1192
1193 rbot = cur;
1194 }
1195 return buf;
1196}
1197
1198static noinline_for_stack
1199char *mac_address_string(char *buf, char *end, u8 *addr,
1200 struct printf_spec spec, const char *fmt)
1201{
1202 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1203 char *p = mac_addr;
1204 int i;
1205 char separator;
1206 bool reversed = false;
1207
1208 if (check_pointer(&buf, end, addr, spec))
1209 return buf;
1210
1211 switch (fmt[1]) {
1212 case 'F':
1213 separator = '-';
1214 break;
1215
1216 case 'R':
1217 reversed = true;
1218 /* fall through */
1219
1220 default:
1221 separator = ':';
1222 break;
1223 }
1224
1225 for (i = 0; i < 6; i++) {
1226 if (reversed)
1227 p = hex_byte_pack(p, addr[5 - i]);
1228 else
1229 p = hex_byte_pack(p, addr[i]);
1230
1231 if (fmt[0] == 'M' && i != 5)
1232 *p++ = separator;
1233 }
1234 *p = '\0';
1235
1236 return string_nocheck(buf, end, mac_addr, spec);
1237}
1238
1239static noinline_for_stack
1240char *ip4_string(char *p, const u8 *addr, const char *fmt)
1241{
1242 int i;
1243 bool leading_zeros = (fmt[0] == 'i');
1244 int index;
1245 int step;
1246
1247 switch (fmt[2]) {
1248 case 'h':
1249#ifdef __BIG_ENDIAN
1250 index = 0;
1251 step = 1;
1252#else
1253 index = 3;
1254 step = -1;
1255#endif
1256 break;
1257 case 'l':
1258 index = 3;
1259 step = -1;
1260 break;
1261 case 'n':
1262 case 'b':
1263 default:
1264 index = 0;
1265 step = 1;
1266 break;
1267 }
1268 for (i = 0; i < 4; i++) {
1269 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1270 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1271 if (leading_zeros) {
1272 if (digits < 3)
1273 *p++ = '0';
1274 if (digits < 2)
1275 *p++ = '0';
1276 }
1277 /* reverse the digits in the quad */
1278 while (digits--)
1279 *p++ = temp[digits];
1280 if (i < 3)
1281 *p++ = '.';
1282 index += step;
1283 }
1284 *p = '\0';
1285
1286 return p;
1287}
1288
1289static noinline_for_stack
1290char *ip6_compressed_string(char *p, const char *addr)
1291{
1292 int i, j, range;
1293 unsigned char zerolength[8];
1294 int longest = 1;
1295 int colonpos = -1;
1296 u16 word;
1297 u8 hi, lo;
1298 bool needcolon = false;
1299 bool useIPv4;
1300 struct in6_addr in6;
1301
1302 memcpy(&in6, addr, sizeof(struct in6_addr));
1303
1304 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1305
1306 memset(zerolength, 0, sizeof(zerolength));
1307
1308 if (useIPv4)
1309 range = 6;
1310 else
1311 range = 8;
1312
1313 /* find position of longest 0 run */
1314 for (i = 0; i < range; i++) {
1315 for (j = i; j < range; j++) {
1316 if (in6.s6_addr16[j] != 0)
1317 break;
1318 zerolength[i]++;
1319 }
1320 }
1321 for (i = 0; i < range; i++) {
1322 if (zerolength[i] > longest) {
1323 longest = zerolength[i];
1324 colonpos = i;
1325 }
1326 }
1327 if (longest == 1) /* don't compress a single 0 */
1328 colonpos = -1;
1329
1330 /* emit address */
1331 for (i = 0; i < range; i++) {
1332 if (i == colonpos) {
1333 if (needcolon || i == 0)
1334 *p++ = ':';
1335 *p++ = ':';
1336 needcolon = false;
1337 i += longest - 1;
1338 continue;
1339 }
1340 if (needcolon) {
1341 *p++ = ':';
1342 needcolon = false;
1343 }
1344 /* hex u16 without leading 0s */
1345 word = ntohs(in6.s6_addr16[i]);
1346 hi = word >> 8;
1347 lo = word & 0xff;
1348 if (hi) {
1349 if (hi > 0x0f)
1350 p = hex_byte_pack(p, hi);
1351 else
1352 *p++ = hex_asc_lo(hi);
1353 p = hex_byte_pack(p, lo);
1354 }
1355 else if (lo > 0x0f)
1356 p = hex_byte_pack(p, lo);
1357 else
1358 *p++ = hex_asc_lo(lo);
1359 needcolon = true;
1360 }
1361
1362 if (useIPv4) {
1363 if (needcolon)
1364 *p++ = ':';
1365 p = ip4_string(p, &in6.s6_addr[12], "I4");
1366 }
1367 *p = '\0';
1368
1369 return p;
1370}
1371
1372static noinline_for_stack
1373char *ip6_string(char *p, const char *addr, const char *fmt)
1374{
1375 int i;
1376
1377 for (i = 0; i < 8; i++) {
1378 p = hex_byte_pack(p, *addr++);
1379 p = hex_byte_pack(p, *addr++);
1380 if (fmt[0] == 'I' && i != 7)
1381 *p++ = ':';
1382 }
1383 *p = '\0';
1384
1385 return p;
1386}
1387
1388static noinline_for_stack
1389char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1390 struct printf_spec spec, const char *fmt)
1391{
1392 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1393
1394 if (fmt[0] == 'I' && fmt[2] == 'c')
1395 ip6_compressed_string(ip6_addr, addr);
1396 else
1397 ip6_string(ip6_addr, addr, fmt);
1398
1399 return string_nocheck(buf, end, ip6_addr, spec);
1400}
1401
1402static noinline_for_stack
1403char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1404 struct printf_spec spec, const char *fmt)
1405{
1406 char ip4_addr[sizeof("255.255.255.255")];
1407
1408 ip4_string(ip4_addr, addr, fmt);
1409
1410 return string_nocheck(buf, end, ip4_addr, spec);
1411}
1412
1413static noinline_for_stack
1414char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1415 struct printf_spec spec, const char *fmt)
1416{
1417 bool have_p = false, have_s = false, have_f = false, have_c = false;
1418 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1419 sizeof(":12345") + sizeof("/123456789") +
1420 sizeof("%1234567890")];
1421 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1422 const u8 *addr = (const u8 *) &sa->sin6_addr;
1423 char fmt6[2] = { fmt[0], '6' };
1424 u8 off = 0;
1425
1426 fmt++;
1427 while (isalpha(*++fmt)) {
1428 switch (*fmt) {
1429 case 'p':
1430 have_p = true;
1431 break;
1432 case 'f':
1433 have_f = true;
1434 break;
1435 case 's':
1436 have_s = true;
1437 break;
1438 case 'c':
1439 have_c = true;
1440 break;
1441 }
1442 }
1443
1444 if (have_p || have_s || have_f) {
1445 *p = '[';
1446 off = 1;
1447 }
1448
1449 if (fmt6[0] == 'I' && have_c)
1450 p = ip6_compressed_string(ip6_addr + off, addr);
1451 else
1452 p = ip6_string(ip6_addr + off, addr, fmt6);
1453
1454 if (have_p || have_s || have_f)
1455 *p++ = ']';
1456
1457 if (have_p) {
1458 *p++ = ':';
1459 p = number(p, pend, ntohs(sa->sin6_port), spec);
1460 }
1461 if (have_f) {
1462 *p++ = '/';
1463 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1464 IPV6_FLOWINFO_MASK), spec);
1465 }
1466 if (have_s) {
1467 *p++ = '%';
1468 p = number(p, pend, sa->sin6_scope_id, spec);
1469 }
1470 *p = '\0';
1471
1472 return string_nocheck(buf, end, ip6_addr, spec);
1473}
1474
1475static noinline_for_stack
1476char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1477 struct printf_spec spec, const char *fmt)
1478{
1479 bool have_p = false;
1480 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1481 char *pend = ip4_addr + sizeof(ip4_addr);
1482 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1483 char fmt4[3] = { fmt[0], '4', 0 };
1484
1485 fmt++;
1486 while (isalpha(*++fmt)) {
1487 switch (*fmt) {
1488 case 'p':
1489 have_p = true;
1490 break;
1491 case 'h':
1492 case 'l':
1493 case 'n':
1494 case 'b':
1495 fmt4[2] = *fmt;
1496 break;
1497 }
1498 }
1499
1500 p = ip4_string(ip4_addr, addr, fmt4);
1501 if (have_p) {
1502 *p++ = ':';
1503 p = number(p, pend, ntohs(sa->sin_port), spec);
1504 }
1505 *p = '\0';
1506
1507 return string_nocheck(buf, end, ip4_addr, spec);
1508}
1509
1510static noinline_for_stack
1511char *ip_addr_string(char *buf, char *end, const void *ptr,
1512 struct printf_spec spec, const char *fmt)
1513{
1514 char *err_fmt_msg;
1515
1516 if (check_pointer(&buf, end, ptr, spec))
1517 return buf;
1518
1519 switch (fmt[1]) {
1520 case '6':
1521 return ip6_addr_string(buf, end, ptr, spec, fmt);
1522 case '4':
1523 return ip4_addr_string(buf, end, ptr, spec, fmt);
1524 case 'S': {
1525 const union {
1526 struct sockaddr raw;
1527 struct sockaddr_in v4;
1528 struct sockaddr_in6 v6;
1529 } *sa = ptr;
1530
1531 switch (sa->raw.sa_family) {
1532 case AF_INET:
1533 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1534 case AF_INET6:
1535 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1536 default:
1537 return error_string(buf, end, "(einval)", spec);
1538 }}
1539 }
1540
1541 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1542 return error_string(buf, end, err_fmt_msg, spec);
1543}
1544
1545static noinline_for_stack
1546char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1547 const char *fmt)
1548{
1549 bool found = true;
1550 int count = 1;
1551 unsigned int flags = 0;
1552 int len;
1553
1554 if (spec.field_width == 0)
1555 return buf; /* nothing to print */
1556
1557 if (check_pointer(&buf, end, addr, spec))
1558 return buf;
1559
1560 do {
1561 switch (fmt[count++]) {
1562 case 'a':
1563 flags |= ESCAPE_ANY;
1564 break;
1565 case 'c':
1566 flags |= ESCAPE_SPECIAL;
1567 break;
1568 case 'h':
1569 flags |= ESCAPE_HEX;
1570 break;
1571 case 'n':
1572 flags |= ESCAPE_NULL;
1573 break;
1574 case 'o':
1575 flags |= ESCAPE_OCTAL;
1576 break;
1577 case 'p':
1578 flags |= ESCAPE_NP;
1579 break;
1580 case 's':
1581 flags |= ESCAPE_SPACE;
1582 break;
1583 default:
1584 found = false;
1585 break;
1586 }
1587 } while (found);
1588
1589 if (!flags)
1590 flags = ESCAPE_ANY_NP;
1591
1592 len = spec.field_width < 0 ? 1 : spec.field_width;
1593
1594 /*
1595 * string_escape_mem() writes as many characters as it can to
1596 * the given buffer, and returns the total size of the output
1597 * had the buffer been big enough.
1598 */
1599 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1600
1601 return buf;
1602}
1603
1604static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1605 struct printf_spec spec, const char *fmt)
1606{
1607 va_list va;
1608
1609 if (check_pointer(&buf, end, va_fmt, spec))
1610 return buf;
1611
1612 va_copy(va, *va_fmt->va);
1613 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1614 va_end(va);
1615
1616 return buf;
1617}
1618
1619static noinline_for_stack
1620char *uuid_string(char *buf, char *end, const u8 *addr,
1621 struct printf_spec spec, const char *fmt)
1622{
1623 char uuid[UUID_STRING_LEN + 1];
1624 char *p = uuid;
1625 int i;
1626 const u8 *index = uuid_index;
1627 bool uc = false;
1628
1629 if (check_pointer(&buf, end, addr, spec))
1630 return buf;
1631
1632 switch (*(++fmt)) {
1633 case 'L':
1634 uc = true; /* fall-through */
1635 case 'l':
1636 index = guid_index;
1637 break;
1638 case 'B':
1639 uc = true;
1640 break;
1641 }
1642
1643 for (i = 0; i < 16; i++) {
1644 if (uc)
1645 p = hex_byte_pack_upper(p, addr[index[i]]);
1646 else
1647 p = hex_byte_pack(p, addr[index[i]]);
1648 switch (i) {
1649 case 3:
1650 case 5:
1651 case 7:
1652 case 9:
1653 *p++ = '-';
1654 break;
1655 }
1656 }
1657
1658 *p = 0;
1659
1660 return string_nocheck(buf, end, uuid, spec);
1661}
1662
1663static noinline_for_stack
1664char *netdev_bits(char *buf, char *end, const void *addr,
1665 struct printf_spec spec, const char *fmt)
1666{
1667 unsigned long long num;
1668 int size;
1669
1670 if (check_pointer(&buf, end, addr, spec))
1671 return buf;
1672
1673 switch (fmt[1]) {
1674 case 'F':
1675 num = *(const netdev_features_t *)addr;
1676 size = sizeof(netdev_features_t);
1677 break;
1678 default:
1679 return error_string(buf, end, "(%pN?)", spec);
1680 }
1681
1682 return special_hex_number(buf, end, num, size);
1683}
1684
1685static noinline_for_stack
1686char *address_val(char *buf, char *end, const void *addr,
1687 struct printf_spec spec, const char *fmt)
1688{
1689 unsigned long long num;
1690 int size;
1691
1692 if (check_pointer(&buf, end, addr, spec))
1693 return buf;
1694
1695 switch (fmt[1]) {
1696 case 'd':
1697 num = *(const dma_addr_t *)addr;
1698 size = sizeof(dma_addr_t);
1699 break;
1700 case 'p':
1701 default:
1702 num = *(const phys_addr_t *)addr;
1703 size = sizeof(phys_addr_t);
1704 break;
1705 }
1706
1707 return special_hex_number(buf, end, num, size);
1708}
1709
1710static noinline_for_stack
1711char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1712{
1713 int year = tm->tm_year + (r ? 0 : 1900);
1714 int mon = tm->tm_mon + (r ? 0 : 1);
1715
1716 buf = number(buf, end, year, default_dec04_spec);
1717 if (buf < end)
1718 *buf = '-';
1719 buf++;
1720
1721 buf = number(buf, end, mon, default_dec02_spec);
1722 if (buf < end)
1723 *buf = '-';
1724 buf++;
1725
1726 return number(buf, end, tm->tm_mday, default_dec02_spec);
1727}
1728
1729static noinline_for_stack
1730char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1731{
1732 buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1733 if (buf < end)
1734 *buf = ':';
1735 buf++;
1736
1737 buf = number(buf, end, tm->tm_min, default_dec02_spec);
1738 if (buf < end)
1739 *buf = ':';
1740 buf++;
1741
1742 return number(buf, end, tm->tm_sec, default_dec02_spec);
1743}
1744
1745static noinline_for_stack
1746char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1747 struct printf_spec spec, const char *fmt)
1748{
1749 bool have_t = true, have_d = true;
1750 bool raw = false;
1751 int count = 2;
1752
1753 if (check_pointer(&buf, end, tm, spec))
1754 return buf;
1755
1756 switch (fmt[count]) {
1757 case 'd':
1758 have_t = false;
1759 count++;
1760 break;
1761 case 't':
1762 have_d = false;
1763 count++;
1764 break;
1765 }
1766
1767 raw = fmt[count] == 'r';
1768
1769 if (have_d)
1770 buf = date_str(buf, end, tm, raw);
1771 if (have_d && have_t) {
1772 /* Respect ISO 8601 */
1773 if (buf < end)
1774 *buf = 'T';
1775 buf++;
1776 }
1777 if (have_t)
1778 buf = time_str(buf, end, tm, raw);
1779
1780 return buf;
1781}
1782
1783static noinline_for_stack
1784char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1785 const char *fmt)
1786{
1787 switch (fmt[1]) {
1788 case 'R':
1789 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1790 default:
1791 return error_string(buf, end, "(%ptR?)", spec);
1792 }
1793}
1794
1795static noinline_for_stack
1796char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1797 const char *fmt)
1798{
1799 if (!IS_ENABLED(CONFIG_HAVE_CLK))
1800 return error_string(buf, end, "(%pC?)", spec);
1801
1802 if (check_pointer(&buf, end, clk, spec))
1803 return buf;
1804
1805 switch (fmt[1]) {
1806 case 'n':
1807 default:
1808#ifdef CONFIG_COMMON_CLK
1809 return string(buf, end, __clk_get_name(clk), spec);
1810#else
1811 return ptr_to_id(buf, end, clk, spec);
1812#endif
1813 }
1814}
1815
1816static
1817char *format_flags(char *buf, char *end, unsigned long flags,
1818 const struct trace_print_flags *names)
1819{
1820 unsigned long mask;
1821
1822 for ( ; flags && names->name; names++) {
1823 mask = names->mask;
1824 if ((flags & mask) != mask)
1825 continue;
1826
1827 buf = string(buf, end, names->name, default_str_spec);
1828
1829 flags &= ~mask;
1830 if (flags) {
1831 if (buf < end)
1832 *buf = '|';
1833 buf++;
1834 }
1835 }
1836
1837 if (flags)
1838 buf = number(buf, end, flags, default_flag_spec);
1839
1840 return buf;
1841}
1842
1843static noinline_for_stack
1844char *flags_string(char *buf, char *end, void *flags_ptr,
1845 struct printf_spec spec, const char *fmt)
1846{
1847 unsigned long flags;
1848 const struct trace_print_flags *names;
1849
1850 if (check_pointer(&buf, end, flags_ptr, spec))
1851 return buf;
1852
1853 switch (fmt[1]) {
1854 case 'p':
1855 flags = *(unsigned long *)flags_ptr;
1856 /* Remove zone id */
1857 flags &= (1UL << NR_PAGEFLAGS) - 1;
1858 names = pageflag_names;
1859 break;
1860 case 'v':
1861 flags = *(unsigned long *)flags_ptr;
1862 names = vmaflag_names;
1863 break;
1864 case 'g':
1865 flags = *(gfp_t *)flags_ptr;
1866 names = gfpflag_names;
1867 break;
1868 default:
1869 return error_string(buf, end, "(%pG?)", spec);
1870 }
1871
1872 return format_flags(buf, end, flags, names);
1873}
1874
1875static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1876{
1877 for ( ; np && depth; depth--)
1878 np = np->parent;
1879
1880 return kbasename(np->full_name);
1881}
1882
1883static noinline_for_stack
1884char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1885{
1886 int depth;
1887 const struct device_node *parent = np->parent;
1888
1889 /* special case for root node */
1890 if (!parent)
1891 return string_nocheck(buf, end, "/", default_str_spec);
1892
1893 for (depth = 0; parent->parent; depth++)
1894 parent = parent->parent;
1895
1896 for ( ; depth >= 0; depth--) {
1897 buf = string_nocheck(buf, end, "/", default_str_spec);
1898 buf = string(buf, end, device_node_name_for_depth(np, depth),
1899 default_str_spec);
1900 }
1901 return buf;
1902}
1903
1904static noinline_for_stack
1905char *device_node_string(char *buf, char *end, struct device_node *dn,
1906 struct printf_spec spec, const char *fmt)
1907{
1908 char tbuf[sizeof("xxxx") + 1];
1909 const char *p;
1910 int ret;
1911 char *buf_start = buf;
1912 struct property *prop;
1913 bool has_mult, pass;
1914 static const struct printf_spec num_spec = {
1915 .flags = SMALL,
1916 .field_width = -1,
1917 .precision = -1,
1918 .base = 10,
1919 };
1920
1921 struct printf_spec str_spec = spec;
1922 str_spec.field_width = -1;
1923
1924 if (!IS_ENABLED(CONFIG_OF))
1925 return error_string(buf, end, "(%pOF?)", spec);
1926
1927 if (check_pointer(&buf, end, dn, spec))
1928 return buf;
1929
1930 /* simple case without anything any more format specifiers */
1931 fmt++;
1932 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1933 fmt = "f";
1934
1935 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1936 int precision;
1937 if (pass) {
1938 if (buf < end)
1939 *buf = ':';
1940 buf++;
1941 }
1942
1943 switch (*fmt) {
1944 case 'f': /* full_name */
1945 buf = device_node_gen_full_name(dn, buf, end);
1946 break;
1947 case 'n': /* name */
1948 p = kbasename(of_node_full_name(dn));
1949 precision = str_spec.precision;
1950 str_spec.precision = strchrnul(p, '@') - p;
1951 buf = string(buf, end, p, str_spec);
1952 str_spec.precision = precision;
1953 break;
1954 case 'p': /* phandle */
1955 buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1956 break;
1957 case 'P': /* path-spec */
1958 p = kbasename(of_node_full_name(dn));
1959 if (!p[1])
1960 p = "/";
1961 buf = string(buf, end, p, str_spec);
1962 break;
1963 case 'F': /* flags */
1964 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1965 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1966 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1967 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1968 tbuf[4] = 0;
1969 buf = string_nocheck(buf, end, tbuf, str_spec);
1970 break;
1971 case 'c': /* major compatible string */
1972 ret = of_property_read_string(dn, "compatible", &p);
1973 if (!ret)
1974 buf = string(buf, end, p, str_spec);
1975 break;
1976 case 'C': /* full compatible string */
1977 has_mult = false;
1978 of_property_for_each_string(dn, "compatible", prop, p) {
1979 if (has_mult)
1980 buf = string_nocheck(buf, end, ",", str_spec);
1981 buf = string_nocheck(buf, end, "\"", str_spec);
1982 buf = string(buf, end, p, str_spec);
1983 buf = string_nocheck(buf, end, "\"", str_spec);
1984
1985 has_mult = true;
1986 }
1987 break;
1988 default:
1989 break;
1990 }
1991 }
1992
1993 return widen_string(buf, buf - buf_start, end, spec);
1994}
1995
1996static char *kobject_string(char *buf, char *end, void *ptr,
1997 struct printf_spec spec, const char *fmt)
1998{
1999 switch (fmt[1]) {
2000 case 'F':
2001 return device_node_string(buf, end, ptr, spec, fmt + 1);
2002 }
2003
2004 return error_string(buf, end, "(%pO?)", spec);
2005}
2006
2007/*
2008 * Show a '%p' thing. A kernel extension is that the '%p' is followed
2009 * by an extra set of alphanumeric characters that are extended format
2010 * specifiers.
2011 *
2012 * Please update scripts/checkpatch.pl when adding/removing conversion
2013 * characters. (Search for "check for vsprintf extension").
2014 *
2015 * Right now we handle:
2016 *
2017 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2018 * - 's' For symbolic direct pointers (or function descriptors) without offset
2019 * - 'F' Same as 'S'
2020 * - 'f' Same as 's'
2021 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
2022 * - 'B' For backtraced symbolic direct pointers with offset
2023 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2024 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2025 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2026 * width which must be explicitly specified either as part of the
2027 * format string '%32b[l]' or through '%*b[l]', [l] selects
2028 * range-list format instead of hex format
2029 * - 'M' For a 6-byte MAC address, it prints the address in the
2030 * usual colon-separated hex notation
2031 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2032 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2033 * with a dash-separated hex notation
2034 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2035 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2036 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2037 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
2038 * [S][pfs]
2039 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2040 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2041 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2042 * IPv6 omits the colons (01020304...0f)
2043 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2044 * [S][pfs]
2045 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2046 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2047 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2048 * - 'I[6S]c' for IPv6 addresses printed as specified by
2049 * http://tools.ietf.org/html/rfc5952
2050 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2051 * of the following flags (see string_escape_mem() for the
2052 * details):
2053 * a - ESCAPE_ANY
2054 * c - ESCAPE_SPECIAL
2055 * h - ESCAPE_HEX
2056 * n - ESCAPE_NULL
2057 * o - ESCAPE_OCTAL
2058 * p - ESCAPE_NP
2059 * s - ESCAPE_SPACE
2060 * By default ESCAPE_ANY_NP is used.
2061 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2062 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2063 * Options for %pU are:
2064 * b big endian lower case hex (default)
2065 * B big endian UPPER case hex
2066 * l little endian lower case hex
2067 * L little endian UPPER case hex
2068 * big endian output byte order is:
2069 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2070 * little endian output byte order is:
2071 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2072 * - 'V' For a struct va_format which contains a format string * and va_list *,
2073 * call vsnprintf(->format, *->va_list).
2074 * Implements a "recursive vsnprintf".
2075 * Do not use this feature without some mechanism to verify the
2076 * correctness of the format string and va_list arguments.
2077 * - 'K' For a kernel pointer that should be hidden from unprivileged users
2078 * - 'NF' For a netdev_features_t
2079 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2080 * a certain separator (' ' by default):
2081 * C colon
2082 * D dash
2083 * N no separator
2084 * The maximum supported length is 64 bytes of the input. Consider
2085 * to use print_hex_dump() for the larger input.
2086 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2087 * (default assumed to be phys_addr_t, passed by reference)
2088 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2089 * - 'D[234]' Same as 'd' but for a struct file
2090 * - 'g' For block_device name (gendisk + partition number)
2091 * - 't[R][dt][r]' For time and date as represented:
2092 * R struct rtc_time
2093 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2094 * (legacy clock framework) of the clock
2095 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2096 * (legacy clock framework) of the clock
2097 * - 'G' For flags to be printed as a collection of symbolic strings that would
2098 * construct the specific value. Supported flags given by option:
2099 * p page flags (see struct page) given as pointer to unsigned long
2100 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2101 * v vma flags (VM_*) given as pointer to unsigned long
2102 * - 'OF[fnpPcCF]' For a device tree object
2103 * Without any optional arguments prints the full_name
2104 * f device node full_name
2105 * n device node name
2106 * p device node phandle
2107 * P device node path spec (name + @unit)
2108 * F device node flags
2109 * c major compatible string
2110 * C full compatible string
2111 * - 'x' For printing the address. Equivalent to "%lx".
2112 *
2113 * ** When making changes please also update:
2114 * Documentation/core-api/printk-formats.rst
2115 *
2116 * Note: The default behaviour (unadorned %p) is to hash the address,
2117 * rendering it useful as a unique identifier.
2118 */
2119static noinline_for_stack
2120char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2121 struct printf_spec spec)
2122{
2123 switch (*fmt) {
2124 case 'F':
2125 case 'f':
2126 case 'S':
2127 case 's':
2128 ptr = dereference_symbol_descriptor(ptr);
2129 /* Fallthrough */
2130 case 'B':
2131 return symbol_string(buf, end, ptr, spec, fmt);
2132 case 'R':
2133 case 'r':
2134 return resource_string(buf, end, ptr, spec, fmt);
2135 case 'h':
2136 return hex_string(buf, end, ptr, spec, fmt);
2137 case 'b':
2138 switch (fmt[1]) {
2139 case 'l':
2140 return bitmap_list_string(buf, end, ptr, spec, fmt);
2141 default:
2142 return bitmap_string(buf, end, ptr, spec, fmt);
2143 }
2144 case 'M': /* Colon separated: 00:01:02:03:04:05 */
2145 case 'm': /* Contiguous: 000102030405 */
2146 /* [mM]F (FDDI) */
2147 /* [mM]R (Reverse order; Bluetooth) */
2148 return mac_address_string(buf, end, ptr, spec, fmt);
2149 case 'I': /* Formatted IP supported
2150 * 4: 1.2.3.4
2151 * 6: 0001:0203:...:0708
2152 * 6c: 1::708 or 1::1.2.3.4
2153 */
2154 case 'i': /* Contiguous:
2155 * 4: 001.002.003.004
2156 * 6: 000102...0f
2157 */
2158 return ip_addr_string(buf, end, ptr, spec, fmt);
2159 case 'E':
2160 return escaped_string(buf, end, ptr, spec, fmt);
2161 case 'U':
2162 return uuid_string(buf, end, ptr, spec, fmt);
2163 case 'V':
2164 return va_format(buf, end, ptr, spec, fmt);
2165 case 'K':
2166 return restricted_pointer(buf, end, ptr, spec);
2167 case 'N':
2168 return netdev_bits(buf, end, ptr, spec, fmt);
2169 case 'a':
2170 return address_val(buf, end, ptr, spec, fmt);
2171 case 'd':
2172 return dentry_name(buf, end, ptr, spec, fmt);
2173 case 't':
2174 return time_and_date(buf, end, ptr, spec, fmt);
2175 case 'C':
2176 return clock(buf, end, ptr, spec, fmt);
2177 case 'D':
2178 return file_dentry_name(buf, end, ptr, spec, fmt);
2179#ifdef CONFIG_BLOCK
2180 case 'g':
2181 return bdev_name(buf, end, ptr, spec, fmt);
2182#endif
2183
2184 case 'G':
2185 return flags_string(buf, end, ptr, spec, fmt);
2186 case 'O':
2187 return kobject_string(buf, end, ptr, spec, fmt);
2188 case 'x':
2189 return pointer_string(buf, end, ptr, spec);
2190 }
2191
2192 /* default is to _not_ leak addresses, hash before printing */
2193 return ptr_to_id(buf, end, ptr, spec);
2194}
2195
2196/*
2197 * Helper function to decode printf style format.
2198 * Each call decode a token from the format and return the
2199 * number of characters read (or likely the delta where it wants
2200 * to go on the next call).
2201 * The decoded token is returned through the parameters
2202 *
2203 * 'h', 'l', or 'L' for integer fields
2204 * 'z' support added 23/7/1999 S.H.
2205 * 'z' changed to 'Z' --davidm 1/25/99
2206 * 'Z' changed to 'z' --adobriyan 2017-01-25
2207 * 't' added for ptrdiff_t
2208 *
2209 * @fmt: the format string
2210 * @type of the token returned
2211 * @flags: various flags such as +, -, # tokens..
2212 * @field_width: overwritten width
2213 * @base: base of the number (octal, hex, ...)
2214 * @precision: precision of a number
2215 * @qualifier: qualifier of a number (long, size_t, ...)
2216 */
2217static noinline_for_stack
2218int format_decode(const char *fmt, struct printf_spec *spec)
2219{
2220 const char *start = fmt;
2221 char qualifier;
2222
2223 /* we finished early by reading the field width */
2224 if (spec->type == FORMAT_TYPE_WIDTH) {
2225 if (spec->field_width < 0) {
2226 spec->field_width = -spec->field_width;
2227 spec->flags |= LEFT;
2228 }
2229 spec->type = FORMAT_TYPE_NONE;
2230 goto precision;
2231 }
2232
2233 /* we finished early by reading the precision */
2234 if (spec->type == FORMAT_TYPE_PRECISION) {
2235 if (spec->precision < 0)
2236 spec->precision = 0;
2237
2238 spec->type = FORMAT_TYPE_NONE;
2239 goto qualifier;
2240 }
2241
2242 /* By default */
2243 spec->type = FORMAT_TYPE_NONE;
2244
2245 for (; *fmt ; ++fmt) {
2246 if (*fmt == '%')
2247 break;
2248 }
2249
2250 /* Return the current non-format string */
2251 if (fmt != start || !*fmt)
2252 return fmt - start;
2253
2254 /* Process flags */
2255 spec->flags = 0;
2256
2257 while (1) { /* this also skips first '%' */
2258 bool found = true;
2259
2260 ++fmt;
2261
2262 switch (*fmt) {
2263 case '-': spec->flags |= LEFT; break;
2264 case '+': spec->flags |= PLUS; break;
2265 case ' ': spec->flags |= SPACE; break;
2266 case '#': spec->flags |= SPECIAL; break;
2267 case '0': spec->flags |= ZEROPAD; break;
2268 default: found = false;
2269 }
2270
2271 if (!found)
2272 break;
2273 }
2274
2275 /* get field width */
2276 spec->field_width = -1;
2277
2278 if (isdigit(*fmt))
2279 spec->field_width = skip_atoi(&fmt);
2280 else if (*fmt == '*') {
2281 /* it's the next argument */
2282 spec->type = FORMAT_TYPE_WIDTH;
2283 return ++fmt - start;
2284 }
2285
2286precision:
2287 /* get the precision */
2288 spec->precision = -1;
2289 if (*fmt == '.') {
2290 ++fmt;
2291 if (isdigit(*fmt)) {
2292 spec->precision = skip_atoi(&fmt);
2293 if (spec->precision < 0)
2294 spec->precision = 0;
2295 } else if (*fmt == '*') {
2296 /* it's the next argument */
2297 spec->type = FORMAT_TYPE_PRECISION;
2298 return ++fmt - start;
2299 }
2300 }
2301
2302qualifier:
2303 /* get the conversion qualifier */
2304 qualifier = 0;
2305 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2306 *fmt == 'z' || *fmt == 't') {
2307 qualifier = *fmt++;
2308 if (unlikely(qualifier == *fmt)) {
2309 if (qualifier == 'l') {
2310 qualifier = 'L';
2311 ++fmt;
2312 } else if (qualifier == 'h') {
2313 qualifier = 'H';
2314 ++fmt;
2315 }
2316 }
2317 }
2318
2319 /* default base */
2320 spec->base = 10;
2321 switch (*fmt) {
2322 case 'c':
2323 spec->type = FORMAT_TYPE_CHAR;
2324 return ++fmt - start;
2325
2326 case 's':
2327 spec->type = FORMAT_TYPE_STR;
2328 return ++fmt - start;
2329
2330 case 'p':
2331 spec->type = FORMAT_TYPE_PTR;
2332 return ++fmt - start;
2333
2334 case '%':
2335 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2336 return ++fmt - start;
2337
2338 /* integer number formats - set up the flags and "break" */
2339 case 'o':
2340 spec->base = 8;
2341 break;
2342
2343 case 'x':
2344 spec->flags |= SMALL;
2345 /* fall through */
2346
2347 case 'X':
2348 spec->base = 16;
2349 break;
2350
2351 case 'd':
2352 case 'i':
2353 spec->flags |= SIGN;
2354 case 'u':
2355 break;
2356
2357 case 'n':
2358 /*
2359 * Since %n poses a greater security risk than
2360 * utility, treat it as any other invalid or
2361 * unsupported format specifier.
2362 */
2363 /* Fall-through */
2364
2365 default:
2366 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2367 spec->type = FORMAT_TYPE_INVALID;
2368 return fmt - start;
2369 }
2370
2371 if (qualifier == 'L')
2372 spec->type = FORMAT_TYPE_LONG_LONG;
2373 else if (qualifier == 'l') {
2374 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2375 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2376 } else if (qualifier == 'z') {
2377 spec->type = FORMAT_TYPE_SIZE_T;
2378 } else if (qualifier == 't') {
2379 spec->type = FORMAT_TYPE_PTRDIFF;
2380 } else if (qualifier == 'H') {
2381 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2382 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2383 } else if (qualifier == 'h') {
2384 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2385 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2386 } else {
2387 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2388 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2389 }
2390
2391 return ++fmt - start;
2392}
2393
2394static void
2395set_field_width(struct printf_spec *spec, int width)
2396{
2397 spec->field_width = width;
2398 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2399 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2400 }
2401}
2402
2403static void
2404set_precision(struct printf_spec *spec, int prec)
2405{
2406 spec->precision = prec;
2407 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2408 spec->precision = clamp(prec, 0, PRECISION_MAX);
2409 }
2410}
2411
2412/**
2413 * vsnprintf - Format a string and place it in a buffer
2414 * @buf: The buffer to place the result into
2415 * @size: The size of the buffer, including the trailing null space
2416 * @fmt: The format string to use
2417 * @args: Arguments for the format string
2418 *
2419 * This function generally follows C99 vsnprintf, but has some
2420 * extensions and a few limitations:
2421 *
2422 * - ``%n`` is unsupported
2423 * - ``%p*`` is handled by pointer()
2424 *
2425 * See pointer() or Documentation/core-api/printk-formats.rst for more
2426 * extensive description.
2427 *
2428 * **Please update the documentation in both places when making changes**
2429 *
2430 * The return value is the number of characters which would
2431 * be generated for the given input, excluding the trailing
2432 * '\0', as per ISO C99. If you want to have the exact
2433 * number of characters written into @buf as return value
2434 * (not including the trailing '\0'), use vscnprintf(). If the
2435 * return is greater than or equal to @size, the resulting
2436 * string is truncated.
2437 *
2438 * If you're not already dealing with a va_list consider using snprintf().
2439 */
2440int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2441{
2442 unsigned long long num;
2443 char *str, *end;
2444 struct printf_spec spec = {0};
2445
2446 /* Reject out-of-range values early. Large positive sizes are
2447 used for unknown buffer sizes. */
2448 if (WARN_ON_ONCE(size > INT_MAX))
2449 return 0;
2450
2451 str = buf;
2452 end = buf + size;
2453
2454 /* Make sure end is always >= buf */
2455 if (end < buf) {
2456 end = ((void *)-1);
2457 size = end - buf;
2458 }
2459
2460 while (*fmt) {
2461 const char *old_fmt = fmt;
2462 int read = format_decode(fmt, &spec);
2463
2464 fmt += read;
2465
2466 switch (spec.type) {
2467 case FORMAT_TYPE_NONE: {
2468 int copy = read;
2469 if (str < end) {
2470 if (copy > end - str)
2471 copy = end - str;
2472 memcpy(str, old_fmt, copy);
2473 }
2474 str += read;
2475 break;
2476 }
2477
2478 case FORMAT_TYPE_WIDTH:
2479 set_field_width(&spec, va_arg(args, int));
2480 break;
2481
2482 case FORMAT_TYPE_PRECISION:
2483 set_precision(&spec, va_arg(args, int));
2484 break;
2485
2486 case FORMAT_TYPE_CHAR: {
2487 char c;
2488
2489 if (!(spec.flags & LEFT)) {
2490 while (--spec.field_width > 0) {
2491 if (str < end)
2492 *str = ' ';
2493 ++str;
2494
2495 }
2496 }
2497 c = (unsigned char) va_arg(args, int);
2498 if (str < end)
2499 *str = c;
2500 ++str;
2501 while (--spec.field_width > 0) {
2502 if (str < end)
2503 *str = ' ';
2504 ++str;
2505 }
2506 break;
2507 }
2508
2509 case FORMAT_TYPE_STR:
2510 str = string(str, end, va_arg(args, char *), spec);
2511 break;
2512
2513 case FORMAT_TYPE_PTR:
2514 str = pointer(fmt, str, end, va_arg(args, void *),
2515 spec);
2516 while (isalnum(*fmt))
2517 fmt++;
2518 break;
2519
2520 case FORMAT_TYPE_PERCENT_CHAR:
2521 if (str < end)
2522 *str = '%';
2523 ++str;
2524 break;
2525
2526 case FORMAT_TYPE_INVALID:
2527 /*
2528 * Presumably the arguments passed gcc's type
2529 * checking, but there is no safe or sane way
2530 * for us to continue parsing the format and
2531 * fetching from the va_list; the remaining
2532 * specifiers and arguments would be out of
2533 * sync.
2534 */
2535 goto out;
2536
2537 default:
2538 switch (spec.type) {
2539 case FORMAT_TYPE_LONG_LONG:
2540 num = va_arg(args, long long);
2541 break;
2542 case FORMAT_TYPE_ULONG:
2543 num = va_arg(args, unsigned long);
2544 break;
2545 case FORMAT_TYPE_LONG:
2546 num = va_arg(args, long);
2547 break;
2548 case FORMAT_TYPE_SIZE_T:
2549 if (spec.flags & SIGN)
2550 num = va_arg(args, ssize_t);
2551 else
2552 num = va_arg(args, size_t);
2553 break;
2554 case FORMAT_TYPE_PTRDIFF:
2555 num = va_arg(args, ptrdiff_t);
2556 break;
2557 case FORMAT_TYPE_UBYTE:
2558 num = (unsigned char) va_arg(args, int);
2559 break;
2560 case FORMAT_TYPE_BYTE:
2561 num = (signed char) va_arg(args, int);
2562 break;
2563 case FORMAT_TYPE_USHORT:
2564 num = (unsigned short) va_arg(args, int);
2565 break;
2566 case FORMAT_TYPE_SHORT:
2567 num = (short) va_arg(args, int);
2568 break;
2569 case FORMAT_TYPE_INT:
2570 num = (int) va_arg(args, int);
2571 break;
2572 default:
2573 num = va_arg(args, unsigned int);
2574 }
2575
2576 str = number(str, end, num, spec);
2577 }
2578 }
2579
2580out:
2581 if (size > 0) {
2582 if (str < end)
2583 *str = '\0';
2584 else
2585 end[-1] = '\0';
2586 }
2587
2588 /* the trailing null byte doesn't count towards the total */
2589 return str-buf;
2590
2591}
2592EXPORT_SYMBOL(vsnprintf);
2593
2594/**
2595 * vscnprintf - Format a string and place it in a buffer
2596 * @buf: The buffer to place the result into
2597 * @size: The size of the buffer, including the trailing null space
2598 * @fmt: The format string to use
2599 * @args: Arguments for the format string
2600 *
2601 * The return value is the number of characters which have been written into
2602 * the @buf not including the trailing '\0'. If @size is == 0 the function
2603 * returns 0.
2604 *
2605 * If you're not already dealing with a va_list consider using scnprintf().
2606 *
2607 * See the vsnprintf() documentation for format string extensions over C99.
2608 */
2609int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2610{
2611 int i;
2612
2613 i = vsnprintf(buf, size, fmt, args);
2614
2615 if (likely(i < size))
2616 return i;
2617 if (size != 0)
2618 return size - 1;
2619 return 0;
2620}
2621EXPORT_SYMBOL(vscnprintf);
2622
2623/**
2624 * snprintf - Format a string and place it in a buffer
2625 * @buf: The buffer to place the result into
2626 * @size: The size of the buffer, including the trailing null space
2627 * @fmt: The format string to use
2628 * @...: Arguments for the format string
2629 *
2630 * The return value is the number of characters which would be
2631 * generated for the given input, excluding the trailing null,
2632 * as per ISO C99. If the return is greater than or equal to
2633 * @size, the resulting string is truncated.
2634 *
2635 * See the vsnprintf() documentation for format string extensions over C99.
2636 */
2637int snprintf(char *buf, size_t size, const char *fmt, ...)
2638{
2639 va_list args;
2640 int i;
2641
2642 va_start(args, fmt);
2643 i = vsnprintf(buf, size, fmt, args);
2644 va_end(args);
2645
2646 return i;
2647}
2648EXPORT_SYMBOL(snprintf);
2649
2650/**
2651 * scnprintf - Format a string and place it in a buffer
2652 * @buf: The buffer to place the result into
2653 * @size: The size of the buffer, including the trailing null space
2654 * @fmt: The format string to use
2655 * @...: Arguments for the format string
2656 *
2657 * The return value is the number of characters written into @buf not including
2658 * the trailing '\0'. If @size is == 0 the function returns 0.
2659 */
2660
2661int scnprintf(char *buf, size_t size, const char *fmt, ...)
2662{
2663 va_list args;
2664 int i;
2665
2666 va_start(args, fmt);
2667 i = vscnprintf(buf, size, fmt, args);
2668 va_end(args);
2669
2670 return i;
2671}
2672EXPORT_SYMBOL(scnprintf);
2673
2674/**
2675 * vsprintf - Format a string and place it in a buffer
2676 * @buf: The buffer to place the result into
2677 * @fmt: The format string to use
2678 * @args: Arguments for the format string
2679 *
2680 * The function returns the number of characters written
2681 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2682 * buffer overflows.
2683 *
2684 * If you're not already dealing with a va_list consider using sprintf().
2685 *
2686 * See the vsnprintf() documentation for format string extensions over C99.
2687 */
2688int vsprintf(char *buf, const char *fmt, va_list args)
2689{
2690 return vsnprintf(buf, INT_MAX, fmt, args);
2691}
2692EXPORT_SYMBOL(vsprintf);
2693
2694/**
2695 * sprintf - Format a string and place it in a buffer
2696 * @buf: The buffer to place the result into
2697 * @fmt: The format string to use
2698 * @...: Arguments for the format string
2699 *
2700 * The function returns the number of characters written
2701 * into @buf. Use snprintf() or scnprintf() in order to avoid
2702 * buffer overflows.
2703 *
2704 * See the vsnprintf() documentation for format string extensions over C99.
2705 */
2706int sprintf(char *buf, const char *fmt, ...)
2707{
2708 va_list args;
2709 int i;
2710
2711 va_start(args, fmt);
2712 i = vsnprintf(buf, INT_MAX, fmt, args);
2713 va_end(args);
2714
2715 return i;
2716}
2717EXPORT_SYMBOL(sprintf);
2718
2719#ifdef CONFIG_BINARY_PRINTF
2720/*
2721 * bprintf service:
2722 * vbin_printf() - VA arguments to binary data
2723 * bstr_printf() - Binary data to text string
2724 */
2725
2726/**
2727 * vbin_printf - Parse a format string and place args' binary value in a buffer
2728 * @bin_buf: The buffer to place args' binary value
2729 * @size: The size of the buffer(by words(32bits), not characters)
2730 * @fmt: The format string to use
2731 * @args: Arguments for the format string
2732 *
2733 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2734 * is skipped.
2735 *
2736 * The return value is the number of words(32bits) which would be generated for
2737 * the given input.
2738 *
2739 * NOTE:
2740 * If the return value is greater than @size, the resulting bin_buf is NOT
2741 * valid for bstr_printf().
2742 */
2743int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2744{
2745 struct printf_spec spec = {0};
2746 char *str, *end;
2747 int width;
2748
2749 str = (char *)bin_buf;
2750 end = (char *)(bin_buf + size);
2751
2752#define save_arg(type) \
2753({ \
2754 unsigned long long value; \
2755 if (sizeof(type) == 8) { \
2756 unsigned long long val8; \
2757 str = PTR_ALIGN(str, sizeof(u32)); \
2758 val8 = va_arg(args, unsigned long long); \
2759 if (str + sizeof(type) <= end) { \
2760 *(u32 *)str = *(u32 *)&val8; \
2761 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
2762 } \
2763 value = val8; \
2764 } else { \
2765 unsigned int val4; \
2766 str = PTR_ALIGN(str, sizeof(type)); \
2767 val4 = va_arg(args, int); \
2768 if (str + sizeof(type) <= end) \
2769 *(typeof(type) *)str = (type)(long)val4; \
2770 value = (unsigned long long)val4; \
2771 } \
2772 str += sizeof(type); \
2773 value; \
2774})
2775
2776 while (*fmt) {
2777 int read = format_decode(fmt, &spec);
2778
2779 fmt += read;
2780
2781 switch (spec.type) {
2782 case FORMAT_TYPE_NONE:
2783 case FORMAT_TYPE_PERCENT_CHAR:
2784 break;
2785 case FORMAT_TYPE_INVALID:
2786 goto out;
2787
2788 case FORMAT_TYPE_WIDTH:
2789 case FORMAT_TYPE_PRECISION:
2790 width = (int)save_arg(int);
2791 /* Pointers may require the width */
2792 if (*fmt == 'p')
2793 set_field_width(&spec, width);
2794 break;
2795
2796 case FORMAT_TYPE_CHAR:
2797 save_arg(char);
2798 break;
2799
2800 case FORMAT_TYPE_STR: {
2801 const char *save_str = va_arg(args, char *);
2802 const char *err_msg;
2803 size_t len;
2804
2805 err_msg = check_pointer_msg(save_str);
2806 if (err_msg)
2807 save_str = err_msg;
2808
2809 len = strlen(save_str) + 1;
2810 if (str + len < end)
2811 memcpy(str, save_str, len);
2812 str += len;
2813 break;
2814 }
2815
2816 case FORMAT_TYPE_PTR:
2817 /* Dereferenced pointers must be done now */
2818 switch (*fmt) {
2819 /* Dereference of functions is still OK */
2820 case 'S':
2821 case 's':
2822 case 'F':
2823 case 'f':
2824 case 'x':
2825 case 'K':
2826 save_arg(void *);
2827 break;
2828 default:
2829 if (!isalnum(*fmt)) {
2830 save_arg(void *);
2831 break;
2832 }
2833 str = pointer(fmt, str, end, va_arg(args, void *),
2834 spec);
2835 if (str + 1 < end)
2836 *str++ = '\0';
2837 else
2838 end[-1] = '\0'; /* Must be nul terminated */
2839 }
2840 /* skip all alphanumeric pointer suffixes */
2841 while (isalnum(*fmt))
2842 fmt++;
2843 break;
2844
2845 default:
2846 switch (spec.type) {
2847
2848 case FORMAT_TYPE_LONG_LONG:
2849 save_arg(long long);
2850 break;
2851 case FORMAT_TYPE_ULONG:
2852 case FORMAT_TYPE_LONG:
2853 save_arg(unsigned long);
2854 break;
2855 case FORMAT_TYPE_SIZE_T:
2856 save_arg(size_t);
2857 break;
2858 case FORMAT_TYPE_PTRDIFF:
2859 save_arg(ptrdiff_t);
2860 break;
2861 case FORMAT_TYPE_UBYTE:
2862 case FORMAT_TYPE_BYTE:
2863 save_arg(char);
2864 break;
2865 case FORMAT_TYPE_USHORT:
2866 case FORMAT_TYPE_SHORT:
2867 save_arg(short);
2868 break;
2869 default:
2870 save_arg(int);
2871 }
2872 }
2873 }
2874
2875out:
2876 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2877#undef save_arg
2878}
2879EXPORT_SYMBOL_GPL(vbin_printf);
2880
2881/**
2882 * bstr_printf - Format a string from binary arguments and place it in a buffer
2883 * @buf: The buffer to place the result into
2884 * @size: The size of the buffer, including the trailing null space
2885 * @fmt: The format string to use
2886 * @bin_buf: Binary arguments for the format string
2887 *
2888 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2889 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2890 * a binary buffer that generated by vbin_printf.
2891 *
2892 * The format follows C99 vsnprintf, but has some extensions:
2893 * see vsnprintf comment for details.
2894 *
2895 * The return value is the number of characters which would
2896 * be generated for the given input, excluding the trailing
2897 * '\0', as per ISO C99. If you want to have the exact
2898 * number of characters written into @buf as return value
2899 * (not including the trailing '\0'), use vscnprintf(). If the
2900 * return is greater than or equal to @size, the resulting
2901 * string is truncated.
2902 */
2903int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2904{
2905 struct printf_spec spec = {0};
2906 char *str, *end;
2907 const char *args = (const char *)bin_buf;
2908
2909 if (WARN_ON_ONCE(size > INT_MAX))
2910 return 0;
2911
2912 str = buf;
2913 end = buf + size;
2914
2915#define get_arg(type) \
2916({ \
2917 typeof(type) value; \
2918 if (sizeof(type) == 8) { \
2919 args = PTR_ALIGN(args, sizeof(u32)); \
2920 *(u32 *)&value = *(u32 *)args; \
2921 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2922 } else { \
2923 args = PTR_ALIGN(args, sizeof(type)); \
2924 value = *(typeof(type) *)args; \
2925 } \
2926 args += sizeof(type); \
2927 value; \
2928})
2929
2930 /* Make sure end is always >= buf */
2931 if (end < buf) {
2932 end = ((void *)-1);
2933 size = end - buf;
2934 }
2935
2936 while (*fmt) {
2937 const char *old_fmt = fmt;
2938 int read = format_decode(fmt, &spec);
2939
2940 fmt += read;
2941
2942 switch (spec.type) {
2943 case FORMAT_TYPE_NONE: {
2944 int copy = read;
2945 if (str < end) {
2946 if (copy > end - str)
2947 copy = end - str;
2948 memcpy(str, old_fmt, copy);
2949 }
2950 str += read;
2951 break;
2952 }
2953
2954 case FORMAT_TYPE_WIDTH:
2955 set_field_width(&spec, get_arg(int));
2956 break;
2957
2958 case FORMAT_TYPE_PRECISION:
2959 set_precision(&spec, get_arg(int));
2960 break;
2961
2962 case FORMAT_TYPE_CHAR: {
2963 char c;
2964
2965 if (!(spec.flags & LEFT)) {
2966 while (--spec.field_width > 0) {
2967 if (str < end)
2968 *str = ' ';
2969 ++str;
2970 }
2971 }
2972 c = (unsigned char) get_arg(char);
2973 if (str < end)
2974 *str = c;
2975 ++str;
2976 while (--spec.field_width > 0) {
2977 if (str < end)
2978 *str = ' ';
2979 ++str;
2980 }
2981 break;
2982 }
2983
2984 case FORMAT_TYPE_STR: {
2985 const char *str_arg = args;
2986 args += strlen(str_arg) + 1;
2987 str = string(str, end, (char *)str_arg, spec);
2988 break;
2989 }
2990
2991 case FORMAT_TYPE_PTR: {
2992 bool process = false;
2993 int copy, len;
2994 /* Non function dereferences were already done */
2995 switch (*fmt) {
2996 case 'S':
2997 case 's':
2998 case 'F':
2999 case 'f':
3000 case 'x':
3001 case 'K':
3002 process = true;
3003 break;
3004 default:
3005 if (!isalnum(*fmt)) {
3006 process = true;
3007 break;
3008 }
3009 /* Pointer dereference was already processed */
3010 if (str < end) {
3011 len = copy = strlen(args);
3012 if (copy > end - str)
3013 copy = end - str;
3014 memcpy(str, args, copy);
3015 str += len;
3016 args += len + 1;
3017 }
3018 }
3019 if (process)
3020 str = pointer(fmt, str, end, get_arg(void *), spec);
3021
3022 while (isalnum(*fmt))
3023 fmt++;
3024 break;
3025 }
3026
3027 case FORMAT_TYPE_PERCENT_CHAR:
3028 if (str < end)
3029 *str = '%';
3030 ++str;
3031 break;
3032
3033 case FORMAT_TYPE_INVALID:
3034 goto out;
3035
3036 default: {
3037 unsigned long long num;
3038
3039 switch (spec.type) {
3040
3041 case FORMAT_TYPE_LONG_LONG:
3042 num = get_arg(long long);
3043 break;
3044 case FORMAT_TYPE_ULONG:
3045 case FORMAT_TYPE_LONG:
3046 num = get_arg(unsigned long);
3047 break;
3048 case FORMAT_TYPE_SIZE_T:
3049 num = get_arg(size_t);
3050 break;
3051 case FORMAT_TYPE_PTRDIFF:
3052 num = get_arg(ptrdiff_t);
3053 break;
3054 case FORMAT_TYPE_UBYTE:
3055 num = get_arg(unsigned char);
3056 break;
3057 case FORMAT_TYPE_BYTE:
3058 num = get_arg(signed char);
3059 break;
3060 case FORMAT_TYPE_USHORT:
3061 num = get_arg(unsigned short);
3062 break;
3063 case FORMAT_TYPE_SHORT:
3064 num = get_arg(short);
3065 break;
3066 case FORMAT_TYPE_UINT:
3067 num = get_arg(unsigned int);
3068 break;
3069 default:
3070 num = get_arg(int);
3071 }
3072
3073 str = number(str, end, num, spec);
3074 } /* default: */
3075 } /* switch(spec.type) */
3076 } /* while(*fmt) */
3077
3078out:
3079 if (size > 0) {
3080 if (str < end)
3081 *str = '\0';
3082 else
3083 end[-1] = '\0';
3084 }
3085
3086#undef get_arg
3087
3088 /* the trailing null byte doesn't count towards the total */
3089 return str - buf;
3090}
3091EXPORT_SYMBOL_GPL(bstr_printf);
3092
3093/**
3094 * bprintf - Parse a format string and place args' binary value in a buffer
3095 * @bin_buf: The buffer to place args' binary value
3096 * @size: The size of the buffer(by words(32bits), not characters)
3097 * @fmt: The format string to use
3098 * @...: Arguments for the format string
3099 *
3100 * The function returns the number of words(u32) written
3101 * into @bin_buf.
3102 */
3103int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3104{
3105 va_list args;
3106 int ret;
3107
3108 va_start(args, fmt);
3109 ret = vbin_printf(bin_buf, size, fmt, args);
3110 va_end(args);
3111
3112 return ret;
3113}
3114EXPORT_SYMBOL_GPL(bprintf);
3115
3116#endif /* CONFIG_BINARY_PRINTF */
3117
3118/**
3119 * vsscanf - Unformat a buffer into a list of arguments
3120 * @buf: input buffer
3121 * @fmt: format of buffer
3122 * @args: arguments
3123 */
3124int vsscanf(const char *buf, const char *fmt, va_list args)
3125{
3126 const char *str = buf;
3127 char *next;
3128 char digit;
3129 int num = 0;
3130 u8 qualifier;
3131 unsigned int base;
3132 union {
3133 long long s;
3134 unsigned long long u;
3135 } val;
3136 s16 field_width;
3137 bool is_sign;
3138
3139 while (*fmt) {
3140 /* skip any white space in format */
3141 /* white space in format matchs any amount of
3142 * white space, including none, in the input.
3143 */
3144 if (isspace(*fmt)) {
3145 fmt = skip_spaces(++fmt);
3146 str = skip_spaces(str);
3147 }
3148
3149 /* anything that is not a conversion must match exactly */
3150 if (*fmt != '%' && *fmt) {
3151 if (*fmt++ != *str++)
3152 break;
3153 continue;
3154 }
3155
3156 if (!*fmt)
3157 break;
3158 ++fmt;
3159
3160 /* skip this conversion.
3161 * advance both strings to next white space
3162 */
3163 if (*fmt == '*') {
3164 if (!*str)
3165 break;
3166 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3167 /* '%*[' not yet supported, invalid format */
3168 if (*fmt == '[')
3169 return num;
3170 fmt++;
3171 }
3172 while (!isspace(*str) && *str)
3173 str++;
3174 continue;
3175 }
3176
3177 /* get field width */
3178 field_width = -1;
3179 if (isdigit(*fmt)) {
3180 field_width = skip_atoi(&fmt);
3181 if (field_width <= 0)
3182 break;
3183 }
3184
3185 /* get conversion qualifier */
3186 qualifier = -1;
3187 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3188 *fmt == 'z') {
3189 qualifier = *fmt++;
3190 if (unlikely(qualifier == *fmt)) {
3191 if (qualifier == 'h') {
3192 qualifier = 'H';
3193 fmt++;
3194 } else if (qualifier == 'l') {
3195 qualifier = 'L';
3196 fmt++;
3197 }
3198 }
3199 }
3200
3201 if (!*fmt)
3202 break;
3203
3204 if (*fmt == 'n') {
3205 /* return number of characters read so far */
3206 *va_arg(args, int *) = str - buf;
3207 ++fmt;
3208 continue;
3209 }
3210
3211 if (!*str)
3212 break;
3213
3214 base = 10;
3215 is_sign = false;
3216
3217 switch (*fmt++) {
3218 case 'c':
3219 {
3220 char *s = (char *)va_arg(args, char*);
3221 if (field_width == -1)
3222 field_width = 1;
3223 do {
3224 *s++ = *str++;
3225 } while (--field_width > 0 && *str);
3226 num++;
3227 }
3228 continue;
3229 case 's':
3230 {
3231 char *s = (char *)va_arg(args, char *);
3232 if (field_width == -1)
3233 field_width = SHRT_MAX;
3234 /* first, skip leading white space in buffer */
3235 str = skip_spaces(str);
3236
3237 /* now copy until next white space */
3238 while (*str && !isspace(*str) && field_width--)
3239 *s++ = *str++;
3240 *s = '\0';
3241 num++;
3242 }
3243 continue;
3244 /*
3245 * Warning: This implementation of the '[' conversion specifier
3246 * deviates from its glibc counterpart in the following ways:
3247 * (1) It does NOT support ranges i.e. '-' is NOT a special
3248 * character
3249 * (2) It cannot match the closing bracket ']' itself
3250 * (3) A field width is required
3251 * (4) '%*[' (discard matching input) is currently not supported
3252 *
3253 * Example usage:
3254 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3255 * buf1, buf2, buf3);
3256 * if (ret < 3)
3257 * // etc..
3258 */
3259 case '[':
3260 {
3261 char *s = (char *)va_arg(args, char *);
3262 DECLARE_BITMAP(set, 256) = {0};
3263 unsigned int len = 0;
3264 bool negate = (*fmt == '^');
3265
3266 /* field width is required */
3267 if (field_width == -1)
3268 return num;
3269
3270 if (negate)
3271 ++fmt;
3272
3273 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3274 set_bit((u8)*fmt, set);
3275
3276 /* no ']' or no character set found */
3277 if (!*fmt || !len)
3278 return num;
3279 ++fmt;
3280
3281 if (negate) {
3282 bitmap_complement(set, set, 256);
3283 /* exclude null '\0' byte */
3284 clear_bit(0, set);
3285 }
3286
3287 /* match must be non-empty */
3288 if (!test_bit((u8)*str, set))
3289 return num;
3290
3291 while (test_bit((u8)*str, set) && field_width--)
3292 *s++ = *str++;
3293 *s = '\0';
3294 ++num;
3295 }
3296 continue;
3297 case 'o':
3298 base = 8;
3299 break;
3300 case 'x':
3301 case 'X':
3302 base = 16;
3303 break;
3304 case 'i':
3305 base = 0;
3306 /* fall through */
3307 case 'd':
3308 is_sign = true;
3309 /* fall through */
3310 case 'u':
3311 break;
3312 case '%':
3313 /* looking for '%' in str */
3314 if (*str++ != '%')
3315 return num;
3316 continue;
3317 default:
3318 /* invalid format; stop here */
3319 return num;
3320 }
3321
3322 /* have some sort of integer conversion.
3323 * first, skip white space in buffer.
3324 */
3325 str = skip_spaces(str);
3326
3327 digit = *str;
3328 if (is_sign && digit == '-')
3329 digit = *(str + 1);
3330
3331 if (!digit
3332 || (base == 16 && !isxdigit(digit))
3333 || (base == 10 && !isdigit(digit))
3334 || (base == 8 && (!isdigit(digit) || digit > '7'))
3335 || (base == 0 && !isdigit(digit)))
3336 break;
3337
3338 if (is_sign)
3339 val.s = qualifier != 'L' ?
3340 simple_strtol(str, &next, base) :
3341 simple_strtoll(str, &next, base);
3342 else
3343 val.u = qualifier != 'L' ?
3344 simple_strtoul(str, &next, base) :
3345 simple_strtoull(str, &next, base);
3346
3347 if (field_width > 0 && next - str > field_width) {
3348 if (base == 0)
3349 _parse_integer_fixup_radix(str, &base);
3350 while (next - str > field_width) {
3351 if (is_sign)
3352 val.s = div_s64(val.s, base);
3353 else
3354 val.u = div_u64(val.u, base);
3355 --next;
3356 }
3357 }
3358
3359 switch (qualifier) {
3360 case 'H': /* that's 'hh' in format */
3361 if (is_sign)
3362 *va_arg(args, signed char *) = val.s;
3363 else
3364 *va_arg(args, unsigned char *) = val.u;
3365 break;
3366 case 'h':
3367 if (is_sign)
3368 *va_arg(args, short *) = val.s;
3369 else
3370 *va_arg(args, unsigned short *) = val.u;
3371 break;
3372 case 'l':
3373 if (is_sign)
3374 *va_arg(args, long *) = val.s;
3375 else
3376 *va_arg(args, unsigned long *) = val.u;
3377 break;
3378 case 'L':
3379 if (is_sign)
3380 *va_arg(args, long long *) = val.s;
3381 else
3382 *va_arg(args, unsigned long long *) = val.u;
3383 break;
3384 case 'z':
3385 *va_arg(args, size_t *) = val.u;
3386 break;
3387 default:
3388 if (is_sign)
3389 *va_arg(args, int *) = val.s;
3390 else
3391 *va_arg(args, unsigned int *) = val.u;
3392 break;
3393 }
3394 num++;
3395
3396 if (!next)
3397 break;
3398 str = next;
3399 }
3400
3401 return num;
3402}
3403EXPORT_SYMBOL(vsscanf);
3404
3405/**
3406 * sscanf - Unformat a buffer into a list of arguments
3407 * @buf: input buffer
3408 * @fmt: formatting of buffer
3409 * @...: resulting arguments
3410 */
3411int sscanf(const char *buf, const char *fmt, ...)
3412{
3413 va_list args;
3414 int i;
3415
3416 va_start(args, fmt);
3417 i = vsscanf(buf, fmt, args);
3418 va_end(args);
3419
3420 return i;
3421}
3422EXPORT_SYMBOL(sscanf);