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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54 * This function is obsolete.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79 * This function is obsolete.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/errname.h>
25#include <linux/module.h> /* for KSYM_SYMBOL_LEN */
26#include <linux/types.h>
27#include <linux/string.h>
28#include <linux/ctype.h>
29#include <linux/kernel.h>
30#include <linux/kallsyms.h>
31#include <linux/math64.h>
32#include <linux/uaccess.h>
33#include <linux/ioport.h>
34#include <linux/dcache.h>
35#include <linux/cred.h>
36#include <linux/rtc.h>
37#include <linux/time.h>
38#include <linux/uuid.h>
39#include <linux/of.h>
40#include <net/addrconf.h>
41#include <linux/siphash.h>
42#include <linux/compiler.h>
43#include <linux/property.h>
44#ifdef CONFIG_BLOCK
45#include <linux/blkdev.h>
46#endif
47
48#include "../mm/internal.h" /* For the trace_print_flags arrays */
49
50#include <asm/page.h> /* for PAGE_SIZE */
51#include <asm/byteorder.h> /* cpu_to_le16 */
52
53#include <linux/string_helpers.h>
54#include "kstrtox.h"
55
56/**
57 * simple_strtoull - convert a string to an unsigned long long
58 * @cp: The start of the string
59 * @endp: A pointer to the end of the parsed string will be placed here
60 * @base: The number base to use
61 *
62 * This function has caveats. Please use kstrtoull instead.
63 */
64unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
65{
66 unsigned long long result;
67 unsigned int rv;
68
69 cp = _parse_integer_fixup_radix(cp, &base);
70 rv = _parse_integer(cp, base, &result);
71 /* FIXME */
72 cp += (rv & ~KSTRTOX_OVERFLOW);
73
74 if (endp)
75 *endp = (char *)cp;
76
77 return result;
78}
79EXPORT_SYMBOL(simple_strtoull);
80
81/**
82 * simple_strtoul - convert a string to an unsigned long
83 * @cp: The start of the string
84 * @endp: A pointer to the end of the parsed string will be placed here
85 * @base: The number base to use
86 *
87 * This function has caveats. Please use kstrtoul instead.
88 */
89unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
90{
91 return simple_strtoull(cp, endp, base);
92}
93EXPORT_SYMBOL(simple_strtoul);
94
95/**
96 * simple_strtol - convert a string to a signed long
97 * @cp: The start of the string
98 * @endp: A pointer to the end of the parsed string will be placed here
99 * @base: The number base to use
100 *
101 * This function has caveats. Please use kstrtol instead.
102 */
103long simple_strtol(const char *cp, char **endp, unsigned int base)
104{
105 if (*cp == '-')
106 return -simple_strtoul(cp + 1, endp, base);
107
108 return simple_strtoul(cp, endp, base);
109}
110EXPORT_SYMBOL(simple_strtol);
111
112/**
113 * simple_strtoll - convert a string to a signed long long
114 * @cp: The start of the string
115 * @endp: A pointer to the end of the parsed string will be placed here
116 * @base: The number base to use
117 *
118 * This function has caveats. Please use kstrtoll instead.
119 */
120long long simple_strtoll(const char *cp, char **endp, unsigned int base)
121{
122 if (*cp == '-')
123 return -simple_strtoull(cp + 1, endp, base);
124
125 return simple_strtoull(cp, endp, base);
126}
127EXPORT_SYMBOL(simple_strtoll);
128
129static noinline_for_stack
130int skip_atoi(const char **s)
131{
132 int i = 0;
133
134 do {
135 i = i*10 + *((*s)++) - '0';
136 } while (isdigit(**s));
137
138 return i;
139}
140
141/*
142 * Decimal conversion is by far the most typical, and is used for
143 * /proc and /sys data. This directly impacts e.g. top performance
144 * with many processes running. We optimize it for speed by emitting
145 * two characters at a time, using a 200 byte lookup table. This
146 * roughly halves the number of multiplications compared to computing
147 * the digits one at a time. Implementation strongly inspired by the
148 * previous version, which in turn used ideas described at
149 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
150 * from the author, Douglas W. Jones).
151 *
152 * It turns out there is precisely one 26 bit fixed-point
153 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
154 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
155 * range happens to be somewhat larger (x <= 1073741898), but that's
156 * irrelevant for our purpose.
157 *
158 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
159 * need a 32x32->64 bit multiply, so we simply use the same constant.
160 *
161 * For dividing a number in the range [100, 10^4-1] by 100, there are
162 * several options. The simplest is (x * 0x147b) >> 19, which is valid
163 * for all x <= 43698.
164 */
165
166static const u16 decpair[100] = {
167#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
168 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
169 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
170 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
171 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
172 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
173 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
174 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
175 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
176 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
177 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
178#undef _
179};
180
181/*
182 * This will print a single '0' even if r == 0, since we would
183 * immediately jump to out_r where two 0s would be written but only
184 * one of them accounted for in buf. This is needed by ip4_string
185 * below. All other callers pass a non-zero value of r.
186*/
187static noinline_for_stack
188char *put_dec_trunc8(char *buf, unsigned r)
189{
190 unsigned q;
191
192 /* 1 <= r < 10^8 */
193 if (r < 100)
194 goto out_r;
195
196 /* 100 <= r < 10^8 */
197 q = (r * (u64)0x28f5c29) >> 32;
198 *((u16 *)buf) = decpair[r - 100*q];
199 buf += 2;
200
201 /* 1 <= q < 10^6 */
202 if (q < 100)
203 goto out_q;
204
205 /* 100 <= q < 10^6 */
206 r = (q * (u64)0x28f5c29) >> 32;
207 *((u16 *)buf) = decpair[q - 100*r];
208 buf += 2;
209
210 /* 1 <= r < 10^4 */
211 if (r < 100)
212 goto out_r;
213
214 /* 100 <= r < 10^4 */
215 q = (r * 0x147b) >> 19;
216 *((u16 *)buf) = decpair[r - 100*q];
217 buf += 2;
218out_q:
219 /* 1 <= q < 100 */
220 r = q;
221out_r:
222 /* 1 <= r < 100 */
223 *((u16 *)buf) = decpair[r];
224 buf += r < 10 ? 1 : 2;
225 return buf;
226}
227
228#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
229static noinline_for_stack
230char *put_dec_full8(char *buf, unsigned r)
231{
232 unsigned q;
233
234 /* 0 <= r < 10^8 */
235 q = (r * (u64)0x28f5c29) >> 32;
236 *((u16 *)buf) = decpair[r - 100*q];
237 buf += 2;
238
239 /* 0 <= q < 10^6 */
240 r = (q * (u64)0x28f5c29) >> 32;
241 *((u16 *)buf) = decpair[q - 100*r];
242 buf += 2;
243
244 /* 0 <= r < 10^4 */
245 q = (r * 0x147b) >> 19;
246 *((u16 *)buf) = decpair[r - 100*q];
247 buf += 2;
248
249 /* 0 <= q < 100 */
250 *((u16 *)buf) = decpair[q];
251 buf += 2;
252 return buf;
253}
254
255static noinline_for_stack
256char *put_dec(char *buf, unsigned long long n)
257{
258 if (n >= 100*1000*1000)
259 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
260 /* 1 <= n <= 1.6e11 */
261 if (n >= 100*1000*1000)
262 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
263 /* 1 <= n < 1e8 */
264 return put_dec_trunc8(buf, n);
265}
266
267#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
268
269static void
270put_dec_full4(char *buf, unsigned r)
271{
272 unsigned q;
273
274 /* 0 <= r < 10^4 */
275 q = (r * 0x147b) >> 19;
276 *((u16 *)buf) = decpair[r - 100*q];
277 buf += 2;
278 /* 0 <= q < 100 */
279 *((u16 *)buf) = decpair[q];
280}
281
282/*
283 * Call put_dec_full4 on x % 10000, return x / 10000.
284 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
285 * holds for all x < 1,128,869,999. The largest value this
286 * helper will ever be asked to convert is 1,125,520,955.
287 * (second call in the put_dec code, assuming n is all-ones).
288 */
289static noinline_for_stack
290unsigned put_dec_helper4(char *buf, unsigned x)
291{
292 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
293
294 put_dec_full4(buf, x - q * 10000);
295 return q;
296}
297
298/* Based on code by Douglas W. Jones found at
299 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
300 * (with permission from the author).
301 * Performs no 64-bit division and hence should be fast on 32-bit machines.
302 */
303static
304char *put_dec(char *buf, unsigned long long n)
305{
306 uint32_t d3, d2, d1, q, h;
307
308 if (n < 100*1000*1000)
309 return put_dec_trunc8(buf, n);
310
311 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
312 h = (n >> 32);
313 d2 = (h ) & 0xffff;
314 d3 = (h >> 16); /* implicit "& 0xffff" */
315
316 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
317 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
318 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
319 q = put_dec_helper4(buf, q);
320
321 q += 7671 * d3 + 9496 * d2 + 6 * d1;
322 q = put_dec_helper4(buf+4, q);
323
324 q += 4749 * d3 + 42 * d2;
325 q = put_dec_helper4(buf+8, q);
326
327 q += 281 * d3;
328 buf += 12;
329 if (q)
330 buf = put_dec_trunc8(buf, q);
331 else while (buf[-1] == '0')
332 --buf;
333
334 return buf;
335}
336
337#endif
338
339/*
340 * Convert passed number to decimal string.
341 * Returns the length of string. On buffer overflow, returns 0.
342 *
343 * If speed is not important, use snprintf(). It's easy to read the code.
344 */
345int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
346{
347 /* put_dec requires 2-byte alignment of the buffer. */
348 char tmp[sizeof(num) * 3] __aligned(2);
349 int idx, len;
350
351 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
352 if (num <= 9) {
353 tmp[0] = '0' + num;
354 len = 1;
355 } else {
356 len = put_dec(tmp, num) - tmp;
357 }
358
359 if (len > size || width > size)
360 return 0;
361
362 if (width > len) {
363 width = width - len;
364 for (idx = 0; idx < width; idx++)
365 buf[idx] = ' ';
366 } else {
367 width = 0;
368 }
369
370 for (idx = 0; idx < len; ++idx)
371 buf[idx + width] = tmp[len - idx - 1];
372
373 return len + width;
374}
375
376#define SIGN 1 /* unsigned/signed, must be 1 */
377#define LEFT 2 /* left justified */
378#define PLUS 4 /* show plus */
379#define SPACE 8 /* space if plus */
380#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
381#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
382#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
383
384static_assert(ZEROPAD == ('0' - ' '));
385static_assert(SMALL == ' ');
386
387enum format_type {
388 FORMAT_TYPE_NONE, /* Just a string part */
389 FORMAT_TYPE_WIDTH,
390 FORMAT_TYPE_PRECISION,
391 FORMAT_TYPE_CHAR,
392 FORMAT_TYPE_STR,
393 FORMAT_TYPE_PTR,
394 FORMAT_TYPE_PERCENT_CHAR,
395 FORMAT_TYPE_INVALID,
396 FORMAT_TYPE_LONG_LONG,
397 FORMAT_TYPE_ULONG,
398 FORMAT_TYPE_LONG,
399 FORMAT_TYPE_UBYTE,
400 FORMAT_TYPE_BYTE,
401 FORMAT_TYPE_USHORT,
402 FORMAT_TYPE_SHORT,
403 FORMAT_TYPE_UINT,
404 FORMAT_TYPE_INT,
405 FORMAT_TYPE_SIZE_T,
406 FORMAT_TYPE_PTRDIFF
407};
408
409struct printf_spec {
410 unsigned int type:8; /* format_type enum */
411 signed int field_width:24; /* width of output field */
412 unsigned int flags:8; /* flags to number() */
413 unsigned int base:8; /* number base, 8, 10 or 16 only */
414 signed int precision:16; /* # of digits/chars */
415} __packed;
416static_assert(sizeof(struct printf_spec) == 8);
417
418#define FIELD_WIDTH_MAX ((1 << 23) - 1)
419#define PRECISION_MAX ((1 << 15) - 1)
420
421static noinline_for_stack
422char *number(char *buf, char *end, unsigned long long num,
423 struct printf_spec spec)
424{
425 /* put_dec requires 2-byte alignment of the buffer. */
426 char tmp[3 * sizeof(num)] __aligned(2);
427 char sign;
428 char locase;
429 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
430 int i;
431 bool is_zero = num == 0LL;
432 int field_width = spec.field_width;
433 int precision = spec.precision;
434
435 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
436 * produces same digits or (maybe lowercased) letters */
437 locase = (spec.flags & SMALL);
438 if (spec.flags & LEFT)
439 spec.flags &= ~ZEROPAD;
440 sign = 0;
441 if (spec.flags & SIGN) {
442 if ((signed long long)num < 0) {
443 sign = '-';
444 num = -(signed long long)num;
445 field_width--;
446 } else if (spec.flags & PLUS) {
447 sign = '+';
448 field_width--;
449 } else if (spec.flags & SPACE) {
450 sign = ' ';
451 field_width--;
452 }
453 }
454 if (need_pfx) {
455 if (spec.base == 16)
456 field_width -= 2;
457 else if (!is_zero)
458 field_width--;
459 }
460
461 /* generate full string in tmp[], in reverse order */
462 i = 0;
463 if (num < spec.base)
464 tmp[i++] = hex_asc_upper[num] | locase;
465 else if (spec.base != 10) { /* 8 or 16 */
466 int mask = spec.base - 1;
467 int shift = 3;
468
469 if (spec.base == 16)
470 shift = 4;
471 do {
472 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
473 num >>= shift;
474 } while (num);
475 } else { /* base 10 */
476 i = put_dec(tmp, num) - tmp;
477 }
478
479 /* printing 100 using %2d gives "100", not "00" */
480 if (i > precision)
481 precision = i;
482 /* leading space padding */
483 field_width -= precision;
484 if (!(spec.flags & (ZEROPAD | LEFT))) {
485 while (--field_width >= 0) {
486 if (buf < end)
487 *buf = ' ';
488 ++buf;
489 }
490 }
491 /* sign */
492 if (sign) {
493 if (buf < end)
494 *buf = sign;
495 ++buf;
496 }
497 /* "0x" / "0" prefix */
498 if (need_pfx) {
499 if (spec.base == 16 || !is_zero) {
500 if (buf < end)
501 *buf = '0';
502 ++buf;
503 }
504 if (spec.base == 16) {
505 if (buf < end)
506 *buf = ('X' | locase);
507 ++buf;
508 }
509 }
510 /* zero or space padding */
511 if (!(spec.flags & LEFT)) {
512 char c = ' ' + (spec.flags & ZEROPAD);
513
514 while (--field_width >= 0) {
515 if (buf < end)
516 *buf = c;
517 ++buf;
518 }
519 }
520 /* hmm even more zero padding? */
521 while (i <= --precision) {
522 if (buf < end)
523 *buf = '0';
524 ++buf;
525 }
526 /* actual digits of result */
527 while (--i >= 0) {
528 if (buf < end)
529 *buf = tmp[i];
530 ++buf;
531 }
532 /* trailing space padding */
533 while (--field_width >= 0) {
534 if (buf < end)
535 *buf = ' ';
536 ++buf;
537 }
538
539 return buf;
540}
541
542static noinline_for_stack
543char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
544{
545 struct printf_spec spec;
546
547 spec.type = FORMAT_TYPE_PTR;
548 spec.field_width = 2 + 2 * size; /* 0x + hex */
549 spec.flags = SPECIAL | SMALL | ZEROPAD;
550 spec.base = 16;
551 spec.precision = -1;
552
553 return number(buf, end, num, spec);
554}
555
556static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
557{
558 size_t size;
559 if (buf >= end) /* nowhere to put anything */
560 return;
561 size = end - buf;
562 if (size <= spaces) {
563 memset(buf, ' ', size);
564 return;
565 }
566 if (len) {
567 if (len > size - spaces)
568 len = size - spaces;
569 memmove(buf + spaces, buf, len);
570 }
571 memset(buf, ' ', spaces);
572}
573
574/*
575 * Handle field width padding for a string.
576 * @buf: current buffer position
577 * @n: length of string
578 * @end: end of output buffer
579 * @spec: for field width and flags
580 * Returns: new buffer position after padding.
581 */
582static noinline_for_stack
583char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
584{
585 unsigned spaces;
586
587 if (likely(n >= spec.field_width))
588 return buf;
589 /* we want to pad the sucker */
590 spaces = spec.field_width - n;
591 if (!(spec.flags & LEFT)) {
592 move_right(buf - n, end, n, spaces);
593 return buf + spaces;
594 }
595 while (spaces--) {
596 if (buf < end)
597 *buf = ' ';
598 ++buf;
599 }
600 return buf;
601}
602
603/* Handle string from a well known address. */
604static char *string_nocheck(char *buf, char *end, const char *s,
605 struct printf_spec spec)
606{
607 int len = 0;
608 int lim = spec.precision;
609
610 while (lim--) {
611 char c = *s++;
612 if (!c)
613 break;
614 if (buf < end)
615 *buf = c;
616 ++buf;
617 ++len;
618 }
619 return widen_string(buf, len, end, spec);
620}
621
622static char *err_ptr(char *buf, char *end, void *ptr,
623 struct printf_spec spec)
624{
625 int err = PTR_ERR(ptr);
626 const char *sym = errname(err);
627
628 if (sym)
629 return string_nocheck(buf, end, sym, spec);
630
631 /*
632 * Somebody passed ERR_PTR(-1234) or some other non-existing
633 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to
634 * printing it as its decimal representation.
635 */
636 spec.flags |= SIGN;
637 spec.base = 10;
638 return number(buf, end, err, spec);
639}
640
641/* Be careful: error messages must fit into the given buffer. */
642static char *error_string(char *buf, char *end, const char *s,
643 struct printf_spec spec)
644{
645 /*
646 * Hard limit to avoid a completely insane messages. It actually
647 * works pretty well because most error messages are in
648 * the many pointer format modifiers.
649 */
650 if (spec.precision == -1)
651 spec.precision = 2 * sizeof(void *);
652
653 return string_nocheck(buf, end, s, spec);
654}
655
656/*
657 * Do not call any complex external code here. Nested printk()/vsprintf()
658 * might cause infinite loops. Failures might break printk() and would
659 * be hard to debug.
660 */
661static const char *check_pointer_msg(const void *ptr)
662{
663 if (!ptr)
664 return "(null)";
665
666 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
667 return "(efault)";
668
669 return NULL;
670}
671
672static int check_pointer(char **buf, char *end, const void *ptr,
673 struct printf_spec spec)
674{
675 const char *err_msg;
676
677 err_msg = check_pointer_msg(ptr);
678 if (err_msg) {
679 *buf = error_string(*buf, end, err_msg, spec);
680 return -EFAULT;
681 }
682
683 return 0;
684}
685
686static noinline_for_stack
687char *string(char *buf, char *end, const char *s,
688 struct printf_spec spec)
689{
690 if (check_pointer(&buf, end, s, spec))
691 return buf;
692
693 return string_nocheck(buf, end, s, spec);
694}
695
696static char *pointer_string(char *buf, char *end,
697 const void *ptr,
698 struct printf_spec spec)
699{
700 spec.base = 16;
701 spec.flags |= SMALL;
702 if (spec.field_width == -1) {
703 spec.field_width = 2 * sizeof(ptr);
704 spec.flags |= ZEROPAD;
705 }
706
707 return number(buf, end, (unsigned long int)ptr, spec);
708}
709
710/* Make pointers available for printing early in the boot sequence. */
711static int debug_boot_weak_hash __ro_after_init;
712
713static int __init debug_boot_weak_hash_enable(char *str)
714{
715 debug_boot_weak_hash = 1;
716 pr_info("debug_boot_weak_hash enabled\n");
717 return 0;
718}
719early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
720
721static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
722static siphash_key_t ptr_key __read_mostly;
723
724static void enable_ptr_key_workfn(struct work_struct *work)
725{
726 get_random_bytes(&ptr_key, sizeof(ptr_key));
727 /* Needs to run from preemptible context */
728 static_branch_disable(¬_filled_random_ptr_key);
729}
730
731static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
732
733static void fill_random_ptr_key(struct random_ready_callback *unused)
734{
735 /* This may be in an interrupt handler. */
736 queue_work(system_unbound_wq, &enable_ptr_key_work);
737}
738
739static struct random_ready_callback random_ready = {
740 .func = fill_random_ptr_key
741};
742
743static int __init initialize_ptr_random(void)
744{
745 int key_size = sizeof(ptr_key);
746 int ret;
747
748 /* Use hw RNG if available. */
749 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
750 static_branch_disable(¬_filled_random_ptr_key);
751 return 0;
752 }
753
754 ret = add_random_ready_callback(&random_ready);
755 if (!ret) {
756 return 0;
757 } else if (ret == -EALREADY) {
758 /* This is in preemptible context */
759 enable_ptr_key_workfn(&enable_ptr_key_work);
760 return 0;
761 }
762
763 return ret;
764}
765early_initcall(initialize_ptr_random);
766
767/* Maps a pointer to a 32 bit unique identifier. */
768static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
769{
770 unsigned long hashval;
771
772 if (static_branch_unlikely(¬_filled_random_ptr_key))
773 return -EAGAIN;
774
775#ifdef CONFIG_64BIT
776 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
777 /*
778 * Mask off the first 32 bits, this makes explicit that we have
779 * modified the address (and 32 bits is plenty for a unique ID).
780 */
781 hashval = hashval & 0xffffffff;
782#else
783 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
784#endif
785 *hashval_out = hashval;
786 return 0;
787}
788
789int ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
790{
791 return __ptr_to_hashval(ptr, hashval_out);
792}
793
794static char *ptr_to_id(char *buf, char *end, const void *ptr,
795 struct printf_spec spec)
796{
797 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
798 unsigned long hashval;
799 int ret;
800
801 /*
802 * Print the real pointer value for NULL and error pointers,
803 * as they are not actual addresses.
804 */
805 if (IS_ERR_OR_NULL(ptr))
806 return pointer_string(buf, end, ptr, spec);
807
808 /* When debugging early boot use non-cryptographically secure hash. */
809 if (unlikely(debug_boot_weak_hash)) {
810 hashval = hash_long((unsigned long)ptr, 32);
811 return pointer_string(buf, end, (const void *)hashval, spec);
812 }
813
814 ret = __ptr_to_hashval(ptr, &hashval);
815 if (ret) {
816 spec.field_width = 2 * sizeof(ptr);
817 /* string length must be less than default_width */
818 return error_string(buf, end, str, spec);
819 }
820
821 return pointer_string(buf, end, (const void *)hashval, spec);
822}
823
824int kptr_restrict __read_mostly;
825
826static noinline_for_stack
827char *restricted_pointer(char *buf, char *end, const void *ptr,
828 struct printf_spec spec)
829{
830 switch (kptr_restrict) {
831 case 0:
832 /* Handle as %p, hash and do _not_ leak addresses. */
833 return ptr_to_id(buf, end, ptr, spec);
834 case 1: {
835 const struct cred *cred;
836
837 /*
838 * kptr_restrict==1 cannot be used in IRQ context
839 * because its test for CAP_SYSLOG would be meaningless.
840 */
841 if (in_irq() || in_serving_softirq() || in_nmi()) {
842 if (spec.field_width == -1)
843 spec.field_width = 2 * sizeof(ptr);
844 return error_string(buf, end, "pK-error", spec);
845 }
846
847 /*
848 * Only print the real pointer value if the current
849 * process has CAP_SYSLOG and is running with the
850 * same credentials it started with. This is because
851 * access to files is checked at open() time, but %pK
852 * checks permission at read() time. We don't want to
853 * leak pointer values if a binary opens a file using
854 * %pK and then elevates privileges before reading it.
855 */
856 cred = current_cred();
857 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
858 !uid_eq(cred->euid, cred->uid) ||
859 !gid_eq(cred->egid, cred->gid))
860 ptr = NULL;
861 break;
862 }
863 case 2:
864 default:
865 /* Always print 0's for %pK */
866 ptr = NULL;
867 break;
868 }
869
870 return pointer_string(buf, end, ptr, spec);
871}
872
873static noinline_for_stack
874char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
875 const char *fmt)
876{
877 const char *array[4], *s;
878 const struct dentry *p;
879 int depth;
880 int i, n;
881
882 switch (fmt[1]) {
883 case '2': case '3': case '4':
884 depth = fmt[1] - '0';
885 break;
886 default:
887 depth = 1;
888 }
889
890 rcu_read_lock();
891 for (i = 0; i < depth; i++, d = p) {
892 if (check_pointer(&buf, end, d, spec)) {
893 rcu_read_unlock();
894 return buf;
895 }
896
897 p = READ_ONCE(d->d_parent);
898 array[i] = READ_ONCE(d->d_name.name);
899 if (p == d) {
900 if (i)
901 array[i] = "";
902 i++;
903 break;
904 }
905 }
906 s = array[--i];
907 for (n = 0; n != spec.precision; n++, buf++) {
908 char c = *s++;
909 if (!c) {
910 if (!i)
911 break;
912 c = '/';
913 s = array[--i];
914 }
915 if (buf < end)
916 *buf = c;
917 }
918 rcu_read_unlock();
919 return widen_string(buf, n, end, spec);
920}
921
922static noinline_for_stack
923char *file_dentry_name(char *buf, char *end, const struct file *f,
924 struct printf_spec spec, const char *fmt)
925{
926 if (check_pointer(&buf, end, f, spec))
927 return buf;
928
929 return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
930}
931#ifdef CONFIG_BLOCK
932static noinline_for_stack
933char *bdev_name(char *buf, char *end, struct block_device *bdev,
934 struct printf_spec spec, const char *fmt)
935{
936 struct gendisk *hd;
937
938 if (check_pointer(&buf, end, bdev, spec))
939 return buf;
940
941 hd = bdev->bd_disk;
942 buf = string(buf, end, hd->disk_name, spec);
943 if (bdev->bd_part->partno) {
944 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
945 if (buf < end)
946 *buf = 'p';
947 buf++;
948 }
949 buf = number(buf, end, bdev->bd_part->partno, spec);
950 }
951 return buf;
952}
953#endif
954
955static noinline_for_stack
956char *symbol_string(char *buf, char *end, void *ptr,
957 struct printf_spec spec, const char *fmt)
958{
959 unsigned long value;
960#ifdef CONFIG_KALLSYMS
961 char sym[KSYM_SYMBOL_LEN];
962#endif
963
964 if (fmt[1] == 'R')
965 ptr = __builtin_extract_return_addr(ptr);
966 value = (unsigned long)ptr;
967
968#ifdef CONFIG_KALLSYMS
969 if (*fmt == 'B')
970 sprint_backtrace(sym, value);
971 else if (*fmt != 's')
972 sprint_symbol(sym, value);
973 else
974 sprint_symbol_no_offset(sym, value);
975
976 return string_nocheck(buf, end, sym, spec);
977#else
978 return special_hex_number(buf, end, value, sizeof(void *));
979#endif
980}
981
982static const struct printf_spec default_str_spec = {
983 .field_width = -1,
984 .precision = -1,
985};
986
987static const struct printf_spec default_flag_spec = {
988 .base = 16,
989 .precision = -1,
990 .flags = SPECIAL | SMALL,
991};
992
993static const struct printf_spec default_dec_spec = {
994 .base = 10,
995 .precision = -1,
996};
997
998static const struct printf_spec default_dec02_spec = {
999 .base = 10,
1000 .field_width = 2,
1001 .precision = -1,
1002 .flags = ZEROPAD,
1003};
1004
1005static const struct printf_spec default_dec04_spec = {
1006 .base = 10,
1007 .field_width = 4,
1008 .precision = -1,
1009 .flags = ZEROPAD,
1010};
1011
1012static noinline_for_stack
1013char *resource_string(char *buf, char *end, struct resource *res,
1014 struct printf_spec spec, const char *fmt)
1015{
1016#ifndef IO_RSRC_PRINTK_SIZE
1017#define IO_RSRC_PRINTK_SIZE 6
1018#endif
1019
1020#ifndef MEM_RSRC_PRINTK_SIZE
1021#define MEM_RSRC_PRINTK_SIZE 10
1022#endif
1023 static const struct printf_spec io_spec = {
1024 .base = 16,
1025 .field_width = IO_RSRC_PRINTK_SIZE,
1026 .precision = -1,
1027 .flags = SPECIAL | SMALL | ZEROPAD,
1028 };
1029 static const struct printf_spec mem_spec = {
1030 .base = 16,
1031 .field_width = MEM_RSRC_PRINTK_SIZE,
1032 .precision = -1,
1033 .flags = SPECIAL | SMALL | ZEROPAD,
1034 };
1035 static const struct printf_spec bus_spec = {
1036 .base = 16,
1037 .field_width = 2,
1038 .precision = -1,
1039 .flags = SMALL | ZEROPAD,
1040 };
1041 static const struct printf_spec str_spec = {
1042 .field_width = -1,
1043 .precision = 10,
1044 .flags = LEFT,
1045 };
1046
1047 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
1048 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
1049#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
1050#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
1051#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
1052#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
1053 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
1054 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
1055
1056 char *p = sym, *pend = sym + sizeof(sym);
1057 int decode = (fmt[0] == 'R') ? 1 : 0;
1058 const struct printf_spec *specp;
1059
1060 if (check_pointer(&buf, end, res, spec))
1061 return buf;
1062
1063 *p++ = '[';
1064 if (res->flags & IORESOURCE_IO) {
1065 p = string_nocheck(p, pend, "io ", str_spec);
1066 specp = &io_spec;
1067 } else if (res->flags & IORESOURCE_MEM) {
1068 p = string_nocheck(p, pend, "mem ", str_spec);
1069 specp = &mem_spec;
1070 } else if (res->flags & IORESOURCE_IRQ) {
1071 p = string_nocheck(p, pend, "irq ", str_spec);
1072 specp = &default_dec_spec;
1073 } else if (res->flags & IORESOURCE_DMA) {
1074 p = string_nocheck(p, pend, "dma ", str_spec);
1075 specp = &default_dec_spec;
1076 } else if (res->flags & IORESOURCE_BUS) {
1077 p = string_nocheck(p, pend, "bus ", str_spec);
1078 specp = &bus_spec;
1079 } else {
1080 p = string_nocheck(p, pend, "??? ", str_spec);
1081 specp = &mem_spec;
1082 decode = 0;
1083 }
1084 if (decode && res->flags & IORESOURCE_UNSET) {
1085 p = string_nocheck(p, pend, "size ", str_spec);
1086 p = number(p, pend, resource_size(res), *specp);
1087 } else {
1088 p = number(p, pend, res->start, *specp);
1089 if (res->start != res->end) {
1090 *p++ = '-';
1091 p = number(p, pend, res->end, *specp);
1092 }
1093 }
1094 if (decode) {
1095 if (res->flags & IORESOURCE_MEM_64)
1096 p = string_nocheck(p, pend, " 64bit", str_spec);
1097 if (res->flags & IORESOURCE_PREFETCH)
1098 p = string_nocheck(p, pend, " pref", str_spec);
1099 if (res->flags & IORESOURCE_WINDOW)
1100 p = string_nocheck(p, pend, " window", str_spec);
1101 if (res->flags & IORESOURCE_DISABLED)
1102 p = string_nocheck(p, pend, " disabled", str_spec);
1103 } else {
1104 p = string_nocheck(p, pend, " flags ", str_spec);
1105 p = number(p, pend, res->flags, default_flag_spec);
1106 }
1107 *p++ = ']';
1108 *p = '\0';
1109
1110 return string_nocheck(buf, end, sym, spec);
1111}
1112
1113static noinline_for_stack
1114char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1115 const char *fmt)
1116{
1117 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
1118 negative value, fallback to the default */
1119 char separator;
1120
1121 if (spec.field_width == 0)
1122 /* nothing to print */
1123 return buf;
1124
1125 if (check_pointer(&buf, end, addr, spec))
1126 return buf;
1127
1128 switch (fmt[1]) {
1129 case 'C':
1130 separator = ':';
1131 break;
1132 case 'D':
1133 separator = '-';
1134 break;
1135 case 'N':
1136 separator = 0;
1137 break;
1138 default:
1139 separator = ' ';
1140 break;
1141 }
1142
1143 if (spec.field_width > 0)
1144 len = min_t(int, spec.field_width, 64);
1145
1146 for (i = 0; i < len; ++i) {
1147 if (buf < end)
1148 *buf = hex_asc_hi(addr[i]);
1149 ++buf;
1150 if (buf < end)
1151 *buf = hex_asc_lo(addr[i]);
1152 ++buf;
1153
1154 if (separator && i != len - 1) {
1155 if (buf < end)
1156 *buf = separator;
1157 ++buf;
1158 }
1159 }
1160
1161 return buf;
1162}
1163
1164static noinline_for_stack
1165char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1166 struct printf_spec spec, const char *fmt)
1167{
1168 const int CHUNKSZ = 32;
1169 int nr_bits = max_t(int, spec.field_width, 0);
1170 int i, chunksz;
1171 bool first = true;
1172
1173 if (check_pointer(&buf, end, bitmap, spec))
1174 return buf;
1175
1176 /* reused to print numbers */
1177 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1178
1179 chunksz = nr_bits & (CHUNKSZ - 1);
1180 if (chunksz == 0)
1181 chunksz = CHUNKSZ;
1182
1183 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1184 for (; i >= 0; i -= CHUNKSZ) {
1185 u32 chunkmask, val;
1186 int word, bit;
1187
1188 chunkmask = ((1ULL << chunksz) - 1);
1189 word = i / BITS_PER_LONG;
1190 bit = i % BITS_PER_LONG;
1191 val = (bitmap[word] >> bit) & chunkmask;
1192
1193 if (!first) {
1194 if (buf < end)
1195 *buf = ',';
1196 buf++;
1197 }
1198 first = false;
1199
1200 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1201 buf = number(buf, end, val, spec);
1202
1203 chunksz = CHUNKSZ;
1204 }
1205 return buf;
1206}
1207
1208static noinline_for_stack
1209char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1210 struct printf_spec spec, const char *fmt)
1211{
1212 int nr_bits = max_t(int, spec.field_width, 0);
1213 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1214 int cur, rbot, rtop;
1215 bool first = true;
1216
1217 if (check_pointer(&buf, end, bitmap, spec))
1218 return buf;
1219
1220 rbot = cur = find_first_bit(bitmap, nr_bits);
1221 while (cur < nr_bits) {
1222 rtop = cur;
1223 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1224 if (cur < nr_bits && cur <= rtop + 1)
1225 continue;
1226
1227 if (!first) {
1228 if (buf < end)
1229 *buf = ',';
1230 buf++;
1231 }
1232 first = false;
1233
1234 buf = number(buf, end, rbot, default_dec_spec);
1235 if (rbot < rtop) {
1236 if (buf < end)
1237 *buf = '-';
1238 buf++;
1239
1240 buf = number(buf, end, rtop, default_dec_spec);
1241 }
1242
1243 rbot = cur;
1244 }
1245 return buf;
1246}
1247
1248static noinline_for_stack
1249char *mac_address_string(char *buf, char *end, u8 *addr,
1250 struct printf_spec spec, const char *fmt)
1251{
1252 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1253 char *p = mac_addr;
1254 int i;
1255 char separator;
1256 bool reversed = false;
1257
1258 if (check_pointer(&buf, end, addr, spec))
1259 return buf;
1260
1261 switch (fmt[1]) {
1262 case 'F':
1263 separator = '-';
1264 break;
1265
1266 case 'R':
1267 reversed = true;
1268 /* fall through */
1269
1270 default:
1271 separator = ':';
1272 break;
1273 }
1274
1275 for (i = 0; i < 6; i++) {
1276 if (reversed)
1277 p = hex_byte_pack(p, addr[5 - i]);
1278 else
1279 p = hex_byte_pack(p, addr[i]);
1280
1281 if (fmt[0] == 'M' && i != 5)
1282 *p++ = separator;
1283 }
1284 *p = '\0';
1285
1286 return string_nocheck(buf, end, mac_addr, spec);
1287}
1288
1289static noinline_for_stack
1290char *ip4_string(char *p, const u8 *addr, const char *fmt)
1291{
1292 int i;
1293 bool leading_zeros = (fmt[0] == 'i');
1294 int index;
1295 int step;
1296
1297 switch (fmt[2]) {
1298 case 'h':
1299#ifdef __BIG_ENDIAN
1300 index = 0;
1301 step = 1;
1302#else
1303 index = 3;
1304 step = -1;
1305#endif
1306 break;
1307 case 'l':
1308 index = 3;
1309 step = -1;
1310 break;
1311 case 'n':
1312 case 'b':
1313 default:
1314 index = 0;
1315 step = 1;
1316 break;
1317 }
1318 for (i = 0; i < 4; i++) {
1319 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1320 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1321 if (leading_zeros) {
1322 if (digits < 3)
1323 *p++ = '0';
1324 if (digits < 2)
1325 *p++ = '0';
1326 }
1327 /* reverse the digits in the quad */
1328 while (digits--)
1329 *p++ = temp[digits];
1330 if (i < 3)
1331 *p++ = '.';
1332 index += step;
1333 }
1334 *p = '\0';
1335
1336 return p;
1337}
1338
1339static noinline_for_stack
1340char *ip6_compressed_string(char *p, const char *addr)
1341{
1342 int i, j, range;
1343 unsigned char zerolength[8];
1344 int longest = 1;
1345 int colonpos = -1;
1346 u16 word;
1347 u8 hi, lo;
1348 bool needcolon = false;
1349 bool useIPv4;
1350 struct in6_addr in6;
1351
1352 memcpy(&in6, addr, sizeof(struct in6_addr));
1353
1354 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1355
1356 memset(zerolength, 0, sizeof(zerolength));
1357
1358 if (useIPv4)
1359 range = 6;
1360 else
1361 range = 8;
1362
1363 /* find position of longest 0 run */
1364 for (i = 0; i < range; i++) {
1365 for (j = i; j < range; j++) {
1366 if (in6.s6_addr16[j] != 0)
1367 break;
1368 zerolength[i]++;
1369 }
1370 }
1371 for (i = 0; i < range; i++) {
1372 if (zerolength[i] > longest) {
1373 longest = zerolength[i];
1374 colonpos = i;
1375 }
1376 }
1377 if (longest == 1) /* don't compress a single 0 */
1378 colonpos = -1;
1379
1380 /* emit address */
1381 for (i = 0; i < range; i++) {
1382 if (i == colonpos) {
1383 if (needcolon || i == 0)
1384 *p++ = ':';
1385 *p++ = ':';
1386 needcolon = false;
1387 i += longest - 1;
1388 continue;
1389 }
1390 if (needcolon) {
1391 *p++ = ':';
1392 needcolon = false;
1393 }
1394 /* hex u16 without leading 0s */
1395 word = ntohs(in6.s6_addr16[i]);
1396 hi = word >> 8;
1397 lo = word & 0xff;
1398 if (hi) {
1399 if (hi > 0x0f)
1400 p = hex_byte_pack(p, hi);
1401 else
1402 *p++ = hex_asc_lo(hi);
1403 p = hex_byte_pack(p, lo);
1404 }
1405 else if (lo > 0x0f)
1406 p = hex_byte_pack(p, lo);
1407 else
1408 *p++ = hex_asc_lo(lo);
1409 needcolon = true;
1410 }
1411
1412 if (useIPv4) {
1413 if (needcolon)
1414 *p++ = ':';
1415 p = ip4_string(p, &in6.s6_addr[12], "I4");
1416 }
1417 *p = '\0';
1418
1419 return p;
1420}
1421
1422static noinline_for_stack
1423char *ip6_string(char *p, const char *addr, const char *fmt)
1424{
1425 int i;
1426
1427 for (i = 0; i < 8; i++) {
1428 p = hex_byte_pack(p, *addr++);
1429 p = hex_byte_pack(p, *addr++);
1430 if (fmt[0] == 'I' && i != 7)
1431 *p++ = ':';
1432 }
1433 *p = '\0';
1434
1435 return p;
1436}
1437
1438static noinline_for_stack
1439char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1440 struct printf_spec spec, const char *fmt)
1441{
1442 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1443
1444 if (fmt[0] == 'I' && fmt[2] == 'c')
1445 ip6_compressed_string(ip6_addr, addr);
1446 else
1447 ip6_string(ip6_addr, addr, fmt);
1448
1449 return string_nocheck(buf, end, ip6_addr, spec);
1450}
1451
1452static noinline_for_stack
1453char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1454 struct printf_spec spec, const char *fmt)
1455{
1456 char ip4_addr[sizeof("255.255.255.255")];
1457
1458 ip4_string(ip4_addr, addr, fmt);
1459
1460 return string_nocheck(buf, end, ip4_addr, spec);
1461}
1462
1463static noinline_for_stack
1464char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1465 struct printf_spec spec, const char *fmt)
1466{
1467 bool have_p = false, have_s = false, have_f = false, have_c = false;
1468 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1469 sizeof(":12345") + sizeof("/123456789") +
1470 sizeof("%1234567890")];
1471 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1472 const u8 *addr = (const u8 *) &sa->sin6_addr;
1473 char fmt6[2] = { fmt[0], '6' };
1474 u8 off = 0;
1475
1476 fmt++;
1477 while (isalpha(*++fmt)) {
1478 switch (*fmt) {
1479 case 'p':
1480 have_p = true;
1481 break;
1482 case 'f':
1483 have_f = true;
1484 break;
1485 case 's':
1486 have_s = true;
1487 break;
1488 case 'c':
1489 have_c = true;
1490 break;
1491 }
1492 }
1493
1494 if (have_p || have_s || have_f) {
1495 *p = '[';
1496 off = 1;
1497 }
1498
1499 if (fmt6[0] == 'I' && have_c)
1500 p = ip6_compressed_string(ip6_addr + off, addr);
1501 else
1502 p = ip6_string(ip6_addr + off, addr, fmt6);
1503
1504 if (have_p || have_s || have_f)
1505 *p++ = ']';
1506
1507 if (have_p) {
1508 *p++ = ':';
1509 p = number(p, pend, ntohs(sa->sin6_port), spec);
1510 }
1511 if (have_f) {
1512 *p++ = '/';
1513 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1514 IPV6_FLOWINFO_MASK), spec);
1515 }
1516 if (have_s) {
1517 *p++ = '%';
1518 p = number(p, pend, sa->sin6_scope_id, spec);
1519 }
1520 *p = '\0';
1521
1522 return string_nocheck(buf, end, ip6_addr, spec);
1523}
1524
1525static noinline_for_stack
1526char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1527 struct printf_spec spec, const char *fmt)
1528{
1529 bool have_p = false;
1530 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1531 char *pend = ip4_addr + sizeof(ip4_addr);
1532 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1533 char fmt4[3] = { fmt[0], '4', 0 };
1534
1535 fmt++;
1536 while (isalpha(*++fmt)) {
1537 switch (*fmt) {
1538 case 'p':
1539 have_p = true;
1540 break;
1541 case 'h':
1542 case 'l':
1543 case 'n':
1544 case 'b':
1545 fmt4[2] = *fmt;
1546 break;
1547 }
1548 }
1549
1550 p = ip4_string(ip4_addr, addr, fmt4);
1551 if (have_p) {
1552 *p++ = ':';
1553 p = number(p, pend, ntohs(sa->sin_port), spec);
1554 }
1555 *p = '\0';
1556
1557 return string_nocheck(buf, end, ip4_addr, spec);
1558}
1559
1560static noinline_for_stack
1561char *ip_addr_string(char *buf, char *end, const void *ptr,
1562 struct printf_spec spec, const char *fmt)
1563{
1564 char *err_fmt_msg;
1565
1566 if (check_pointer(&buf, end, ptr, spec))
1567 return buf;
1568
1569 switch (fmt[1]) {
1570 case '6':
1571 return ip6_addr_string(buf, end, ptr, spec, fmt);
1572 case '4':
1573 return ip4_addr_string(buf, end, ptr, spec, fmt);
1574 case 'S': {
1575 const union {
1576 struct sockaddr raw;
1577 struct sockaddr_in v4;
1578 struct sockaddr_in6 v6;
1579 } *sa = ptr;
1580
1581 switch (sa->raw.sa_family) {
1582 case AF_INET:
1583 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1584 case AF_INET6:
1585 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1586 default:
1587 return error_string(buf, end, "(einval)", spec);
1588 }}
1589 }
1590
1591 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1592 return error_string(buf, end, err_fmt_msg, spec);
1593}
1594
1595static noinline_for_stack
1596char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1597 const char *fmt)
1598{
1599 bool found = true;
1600 int count = 1;
1601 unsigned int flags = 0;
1602 int len;
1603
1604 if (spec.field_width == 0)
1605 return buf; /* nothing to print */
1606
1607 if (check_pointer(&buf, end, addr, spec))
1608 return buf;
1609
1610 do {
1611 switch (fmt[count++]) {
1612 case 'a':
1613 flags |= ESCAPE_ANY;
1614 break;
1615 case 'c':
1616 flags |= ESCAPE_SPECIAL;
1617 break;
1618 case 'h':
1619 flags |= ESCAPE_HEX;
1620 break;
1621 case 'n':
1622 flags |= ESCAPE_NULL;
1623 break;
1624 case 'o':
1625 flags |= ESCAPE_OCTAL;
1626 break;
1627 case 'p':
1628 flags |= ESCAPE_NP;
1629 break;
1630 case 's':
1631 flags |= ESCAPE_SPACE;
1632 break;
1633 default:
1634 found = false;
1635 break;
1636 }
1637 } while (found);
1638
1639 if (!flags)
1640 flags = ESCAPE_ANY_NP;
1641
1642 len = spec.field_width < 0 ? 1 : spec.field_width;
1643
1644 /*
1645 * string_escape_mem() writes as many characters as it can to
1646 * the given buffer, and returns the total size of the output
1647 * had the buffer been big enough.
1648 */
1649 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1650
1651 return buf;
1652}
1653
1654static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1655 struct printf_spec spec, const char *fmt)
1656{
1657 va_list va;
1658
1659 if (check_pointer(&buf, end, va_fmt, spec))
1660 return buf;
1661
1662 va_copy(va, *va_fmt->va);
1663 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1664 va_end(va);
1665
1666 return buf;
1667}
1668
1669static noinline_for_stack
1670char *uuid_string(char *buf, char *end, const u8 *addr,
1671 struct printf_spec spec, const char *fmt)
1672{
1673 char uuid[UUID_STRING_LEN + 1];
1674 char *p = uuid;
1675 int i;
1676 const u8 *index = uuid_index;
1677 bool uc = false;
1678
1679 if (check_pointer(&buf, end, addr, spec))
1680 return buf;
1681
1682 switch (*(++fmt)) {
1683 case 'L':
1684 uc = true;
1685 /* fall through */
1686 case 'l':
1687 index = guid_index;
1688 break;
1689 case 'B':
1690 uc = true;
1691 break;
1692 }
1693
1694 for (i = 0; i < 16; i++) {
1695 if (uc)
1696 p = hex_byte_pack_upper(p, addr[index[i]]);
1697 else
1698 p = hex_byte_pack(p, addr[index[i]]);
1699 switch (i) {
1700 case 3:
1701 case 5:
1702 case 7:
1703 case 9:
1704 *p++ = '-';
1705 break;
1706 }
1707 }
1708
1709 *p = 0;
1710
1711 return string_nocheck(buf, end, uuid, spec);
1712}
1713
1714static noinline_for_stack
1715char *netdev_bits(char *buf, char *end, const void *addr,
1716 struct printf_spec spec, const char *fmt)
1717{
1718 unsigned long long num;
1719 int size;
1720
1721 if (check_pointer(&buf, end, addr, spec))
1722 return buf;
1723
1724 switch (fmt[1]) {
1725 case 'F':
1726 num = *(const netdev_features_t *)addr;
1727 size = sizeof(netdev_features_t);
1728 break;
1729 default:
1730 return error_string(buf, end, "(%pN?)", spec);
1731 }
1732
1733 return special_hex_number(buf, end, num, size);
1734}
1735
1736static noinline_for_stack
1737char *address_val(char *buf, char *end, const void *addr,
1738 struct printf_spec spec, const char *fmt)
1739{
1740 unsigned long long num;
1741 int size;
1742
1743 if (check_pointer(&buf, end, addr, spec))
1744 return buf;
1745
1746 switch (fmt[1]) {
1747 case 'd':
1748 num = *(const dma_addr_t *)addr;
1749 size = sizeof(dma_addr_t);
1750 break;
1751 case 'p':
1752 default:
1753 num = *(const phys_addr_t *)addr;
1754 size = sizeof(phys_addr_t);
1755 break;
1756 }
1757
1758 return special_hex_number(buf, end, num, size);
1759}
1760
1761static noinline_for_stack
1762char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1763{
1764 int year = tm->tm_year + (r ? 0 : 1900);
1765 int mon = tm->tm_mon + (r ? 0 : 1);
1766
1767 buf = number(buf, end, year, default_dec04_spec);
1768 if (buf < end)
1769 *buf = '-';
1770 buf++;
1771
1772 buf = number(buf, end, mon, default_dec02_spec);
1773 if (buf < end)
1774 *buf = '-';
1775 buf++;
1776
1777 return number(buf, end, tm->tm_mday, default_dec02_spec);
1778}
1779
1780static noinline_for_stack
1781char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1782{
1783 buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1784 if (buf < end)
1785 *buf = ':';
1786 buf++;
1787
1788 buf = number(buf, end, tm->tm_min, default_dec02_spec);
1789 if (buf < end)
1790 *buf = ':';
1791 buf++;
1792
1793 return number(buf, end, tm->tm_sec, default_dec02_spec);
1794}
1795
1796static noinline_for_stack
1797char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1798 struct printf_spec spec, const char *fmt)
1799{
1800 bool have_t = true, have_d = true;
1801 bool raw = false;
1802 int count = 2;
1803
1804 if (check_pointer(&buf, end, tm, spec))
1805 return buf;
1806
1807 switch (fmt[count]) {
1808 case 'd':
1809 have_t = false;
1810 count++;
1811 break;
1812 case 't':
1813 have_d = false;
1814 count++;
1815 break;
1816 }
1817
1818 raw = fmt[count] == 'r';
1819
1820 if (have_d)
1821 buf = date_str(buf, end, tm, raw);
1822 if (have_d && have_t) {
1823 /* Respect ISO 8601 */
1824 if (buf < end)
1825 *buf = 'T';
1826 buf++;
1827 }
1828 if (have_t)
1829 buf = time_str(buf, end, tm, raw);
1830
1831 return buf;
1832}
1833
1834static noinline_for_stack
1835char *time64_str(char *buf, char *end, const time64_t time,
1836 struct printf_spec spec, const char *fmt)
1837{
1838 struct rtc_time rtc_time;
1839 struct tm tm;
1840
1841 time64_to_tm(time, 0, &tm);
1842
1843 rtc_time.tm_sec = tm.tm_sec;
1844 rtc_time.tm_min = tm.tm_min;
1845 rtc_time.tm_hour = tm.tm_hour;
1846 rtc_time.tm_mday = tm.tm_mday;
1847 rtc_time.tm_mon = tm.tm_mon;
1848 rtc_time.tm_year = tm.tm_year;
1849 rtc_time.tm_wday = tm.tm_wday;
1850 rtc_time.tm_yday = tm.tm_yday;
1851
1852 rtc_time.tm_isdst = 0;
1853
1854 return rtc_str(buf, end, &rtc_time, spec, fmt);
1855}
1856
1857static noinline_for_stack
1858char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1859 const char *fmt)
1860{
1861 switch (fmt[1]) {
1862 case 'R':
1863 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1864 case 'T':
1865 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt);
1866 default:
1867 return error_string(buf, end, "(%pt?)", spec);
1868 }
1869}
1870
1871static noinline_for_stack
1872char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1873 const char *fmt)
1874{
1875 if (!IS_ENABLED(CONFIG_HAVE_CLK))
1876 return error_string(buf, end, "(%pC?)", spec);
1877
1878 if (check_pointer(&buf, end, clk, spec))
1879 return buf;
1880
1881 switch (fmt[1]) {
1882 case 'n':
1883 default:
1884#ifdef CONFIG_COMMON_CLK
1885 return string(buf, end, __clk_get_name(clk), spec);
1886#else
1887 return ptr_to_id(buf, end, clk, spec);
1888#endif
1889 }
1890}
1891
1892static
1893char *format_flags(char *buf, char *end, unsigned long flags,
1894 const struct trace_print_flags *names)
1895{
1896 unsigned long mask;
1897
1898 for ( ; flags && names->name; names++) {
1899 mask = names->mask;
1900 if ((flags & mask) != mask)
1901 continue;
1902
1903 buf = string(buf, end, names->name, default_str_spec);
1904
1905 flags &= ~mask;
1906 if (flags) {
1907 if (buf < end)
1908 *buf = '|';
1909 buf++;
1910 }
1911 }
1912
1913 if (flags)
1914 buf = number(buf, end, flags, default_flag_spec);
1915
1916 return buf;
1917}
1918
1919static noinline_for_stack
1920char *flags_string(char *buf, char *end, void *flags_ptr,
1921 struct printf_spec spec, const char *fmt)
1922{
1923 unsigned long flags;
1924 const struct trace_print_flags *names;
1925
1926 if (check_pointer(&buf, end, flags_ptr, spec))
1927 return buf;
1928
1929 switch (fmt[1]) {
1930 case 'p':
1931 flags = *(unsigned long *)flags_ptr;
1932 /* Remove zone id */
1933 flags &= (1UL << NR_PAGEFLAGS) - 1;
1934 names = pageflag_names;
1935 break;
1936 case 'v':
1937 flags = *(unsigned long *)flags_ptr;
1938 names = vmaflag_names;
1939 break;
1940 case 'g':
1941 flags = (__force unsigned long)(*(gfp_t *)flags_ptr);
1942 names = gfpflag_names;
1943 break;
1944 default:
1945 return error_string(buf, end, "(%pG?)", spec);
1946 }
1947
1948 return format_flags(buf, end, flags, names);
1949}
1950
1951static noinline_for_stack
1952char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf,
1953 char *end)
1954{
1955 int depth;
1956
1957 /* Loop starting from the root node to the current node. */
1958 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) {
1959 struct fwnode_handle *__fwnode =
1960 fwnode_get_nth_parent(fwnode, depth);
1961
1962 buf = string(buf, end, fwnode_get_name_prefix(__fwnode),
1963 default_str_spec);
1964 buf = string(buf, end, fwnode_get_name(__fwnode),
1965 default_str_spec);
1966
1967 fwnode_handle_put(__fwnode);
1968 }
1969
1970 return buf;
1971}
1972
1973static noinline_for_stack
1974char *device_node_string(char *buf, char *end, struct device_node *dn,
1975 struct printf_spec spec, const char *fmt)
1976{
1977 char tbuf[sizeof("xxxx") + 1];
1978 const char *p;
1979 int ret;
1980 char *buf_start = buf;
1981 struct property *prop;
1982 bool has_mult, pass;
1983
1984 struct printf_spec str_spec = spec;
1985 str_spec.field_width = -1;
1986
1987 if (fmt[0] != 'F')
1988 return error_string(buf, end, "(%pO?)", spec);
1989
1990 if (!IS_ENABLED(CONFIG_OF))
1991 return error_string(buf, end, "(%pOF?)", spec);
1992
1993 if (check_pointer(&buf, end, dn, spec))
1994 return buf;
1995
1996 /* simple case without anything any more format specifiers */
1997 fmt++;
1998 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1999 fmt = "f";
2000
2001 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
2002 int precision;
2003 if (pass) {
2004 if (buf < end)
2005 *buf = ':';
2006 buf++;
2007 }
2008
2009 switch (*fmt) {
2010 case 'f': /* full_name */
2011 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf,
2012 end);
2013 break;
2014 case 'n': /* name */
2015 p = fwnode_get_name(of_fwnode_handle(dn));
2016 precision = str_spec.precision;
2017 str_spec.precision = strchrnul(p, '@') - p;
2018 buf = string(buf, end, p, str_spec);
2019 str_spec.precision = precision;
2020 break;
2021 case 'p': /* phandle */
2022 buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec);
2023 break;
2024 case 'P': /* path-spec */
2025 p = fwnode_get_name(of_fwnode_handle(dn));
2026 if (!p[1])
2027 p = "/";
2028 buf = string(buf, end, p, str_spec);
2029 break;
2030 case 'F': /* flags */
2031 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
2032 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
2033 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
2034 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
2035 tbuf[4] = 0;
2036 buf = string_nocheck(buf, end, tbuf, str_spec);
2037 break;
2038 case 'c': /* major compatible string */
2039 ret = of_property_read_string(dn, "compatible", &p);
2040 if (!ret)
2041 buf = string(buf, end, p, str_spec);
2042 break;
2043 case 'C': /* full compatible string */
2044 has_mult = false;
2045 of_property_for_each_string(dn, "compatible", prop, p) {
2046 if (has_mult)
2047 buf = string_nocheck(buf, end, ",", str_spec);
2048 buf = string_nocheck(buf, end, "\"", str_spec);
2049 buf = string(buf, end, p, str_spec);
2050 buf = string_nocheck(buf, end, "\"", str_spec);
2051
2052 has_mult = true;
2053 }
2054 break;
2055 default:
2056 break;
2057 }
2058 }
2059
2060 return widen_string(buf, buf - buf_start, end, spec);
2061}
2062
2063static noinline_for_stack
2064char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode,
2065 struct printf_spec spec, const char *fmt)
2066{
2067 struct printf_spec str_spec = spec;
2068 char *buf_start = buf;
2069
2070 str_spec.field_width = -1;
2071
2072 if (*fmt != 'w')
2073 return error_string(buf, end, "(%pf?)", spec);
2074
2075 if (check_pointer(&buf, end, fwnode, spec))
2076 return buf;
2077
2078 fmt++;
2079
2080 switch (*fmt) {
2081 case 'P': /* name */
2082 buf = string(buf, end, fwnode_get_name(fwnode), str_spec);
2083 break;
2084 case 'f': /* full_name */
2085 default:
2086 buf = fwnode_full_name_string(fwnode, buf, end);
2087 break;
2088 }
2089
2090 return widen_string(buf, buf - buf_start, end, spec);
2091}
2092
2093/*
2094 * Show a '%p' thing. A kernel extension is that the '%p' is followed
2095 * by an extra set of alphanumeric characters that are extended format
2096 * specifiers.
2097 *
2098 * Please update scripts/checkpatch.pl when adding/removing conversion
2099 * characters. (Search for "check for vsprintf extension").
2100 *
2101 * Right now we handle:
2102 *
2103 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2104 * - 's' For symbolic direct pointers (or function descriptors) without offset
2105 * - '[Ss]R' as above with __builtin_extract_return_addr() translation
2106 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of
2107 * %ps and %pS. Be careful when re-using these specifiers.
2108 * - 'B' For backtraced symbolic direct pointers with offset
2109 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2110 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2111 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2112 * width which must be explicitly specified either as part of the
2113 * format string '%32b[l]' or through '%*b[l]', [l] selects
2114 * range-list format instead of hex format
2115 * - 'M' For a 6-byte MAC address, it prints the address in the
2116 * usual colon-separated hex notation
2117 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2118 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2119 * with a dash-separated hex notation
2120 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2121 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2122 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2123 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
2124 * [S][pfs]
2125 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2126 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2127 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2128 * IPv6 omits the colons (01020304...0f)
2129 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2130 * [S][pfs]
2131 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2132 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2133 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2134 * - 'I[6S]c' for IPv6 addresses printed as specified by
2135 * https://tools.ietf.org/html/rfc5952
2136 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2137 * of the following flags (see string_escape_mem() for the
2138 * details):
2139 * a - ESCAPE_ANY
2140 * c - ESCAPE_SPECIAL
2141 * h - ESCAPE_HEX
2142 * n - ESCAPE_NULL
2143 * o - ESCAPE_OCTAL
2144 * p - ESCAPE_NP
2145 * s - ESCAPE_SPACE
2146 * By default ESCAPE_ANY_NP is used.
2147 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2148 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2149 * Options for %pU are:
2150 * b big endian lower case hex (default)
2151 * B big endian UPPER case hex
2152 * l little endian lower case hex
2153 * L little endian UPPER case hex
2154 * big endian output byte order is:
2155 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2156 * little endian output byte order is:
2157 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2158 * - 'V' For a struct va_format which contains a format string * and va_list *,
2159 * call vsnprintf(->format, *->va_list).
2160 * Implements a "recursive vsnprintf".
2161 * Do not use this feature without some mechanism to verify the
2162 * correctness of the format string and va_list arguments.
2163 * - 'K' For a kernel pointer that should be hidden from unprivileged users
2164 * - 'NF' For a netdev_features_t
2165 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2166 * a certain separator (' ' by default):
2167 * C colon
2168 * D dash
2169 * N no separator
2170 * The maximum supported length is 64 bytes of the input. Consider
2171 * to use print_hex_dump() for the larger input.
2172 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2173 * (default assumed to be phys_addr_t, passed by reference)
2174 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2175 * - 'D[234]' Same as 'd' but for a struct file
2176 * - 'g' For block_device name (gendisk + partition number)
2177 * - 't[RT][dt][r]' For time and date as represented by:
2178 * R struct rtc_time
2179 * T time64_t
2180 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2181 * (legacy clock framework) of the clock
2182 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2183 * (legacy clock framework) of the clock
2184 * - 'G' For flags to be printed as a collection of symbolic strings that would
2185 * construct the specific value. Supported flags given by option:
2186 * p page flags (see struct page) given as pointer to unsigned long
2187 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2188 * v vma flags (VM_*) given as pointer to unsigned long
2189 * - 'OF[fnpPcCF]' For a device tree object
2190 * Without any optional arguments prints the full_name
2191 * f device node full_name
2192 * n device node name
2193 * p device node phandle
2194 * P device node path spec (name + @unit)
2195 * F device node flags
2196 * c major compatible string
2197 * C full compatible string
2198 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer
2199 * Without an option prints the full name of the node
2200 * f full name
2201 * P node name, including a possible unit address
2202 * - 'x' For printing the address. Equivalent to "%lx".
2203 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of
2204 * bpf_trace_printk() where [ku] prefix specifies either kernel (k)
2205 * or user (u) memory to probe, and:
2206 * s a string, equivalent to "%s" on direct vsnprintf() use
2207 *
2208 * ** When making changes please also update:
2209 * Documentation/core-api/printk-formats.rst
2210 *
2211 * Note: The default behaviour (unadorned %p) is to hash the address,
2212 * rendering it useful as a unique identifier.
2213 */
2214static noinline_for_stack
2215char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2216 struct printf_spec spec)
2217{
2218 switch (*fmt) {
2219 case 'S':
2220 case 's':
2221 ptr = dereference_symbol_descriptor(ptr);
2222 /* fall through */
2223 case 'B':
2224 return symbol_string(buf, end, ptr, spec, fmt);
2225 case 'R':
2226 case 'r':
2227 return resource_string(buf, end, ptr, spec, fmt);
2228 case 'h':
2229 return hex_string(buf, end, ptr, spec, fmt);
2230 case 'b':
2231 switch (fmt[1]) {
2232 case 'l':
2233 return bitmap_list_string(buf, end, ptr, spec, fmt);
2234 default:
2235 return bitmap_string(buf, end, ptr, spec, fmt);
2236 }
2237 case 'M': /* Colon separated: 00:01:02:03:04:05 */
2238 case 'm': /* Contiguous: 000102030405 */
2239 /* [mM]F (FDDI) */
2240 /* [mM]R (Reverse order; Bluetooth) */
2241 return mac_address_string(buf, end, ptr, spec, fmt);
2242 case 'I': /* Formatted IP supported
2243 * 4: 1.2.3.4
2244 * 6: 0001:0203:...:0708
2245 * 6c: 1::708 or 1::1.2.3.4
2246 */
2247 case 'i': /* Contiguous:
2248 * 4: 001.002.003.004
2249 * 6: 000102...0f
2250 */
2251 return ip_addr_string(buf, end, ptr, spec, fmt);
2252 case 'E':
2253 return escaped_string(buf, end, ptr, spec, fmt);
2254 case 'U':
2255 return uuid_string(buf, end, ptr, spec, fmt);
2256 case 'V':
2257 return va_format(buf, end, ptr, spec, fmt);
2258 case 'K':
2259 return restricted_pointer(buf, end, ptr, spec);
2260 case 'N':
2261 return netdev_bits(buf, end, ptr, spec, fmt);
2262 case 'a':
2263 return address_val(buf, end, ptr, spec, fmt);
2264 case 'd':
2265 return dentry_name(buf, end, ptr, spec, fmt);
2266 case 't':
2267 return time_and_date(buf, end, ptr, spec, fmt);
2268 case 'C':
2269 return clock(buf, end, ptr, spec, fmt);
2270 case 'D':
2271 return file_dentry_name(buf, end, ptr, spec, fmt);
2272#ifdef CONFIG_BLOCK
2273 case 'g':
2274 return bdev_name(buf, end, ptr, spec, fmt);
2275#endif
2276
2277 case 'G':
2278 return flags_string(buf, end, ptr, spec, fmt);
2279 case 'O':
2280 return device_node_string(buf, end, ptr, spec, fmt + 1);
2281 case 'f':
2282 return fwnode_string(buf, end, ptr, spec, fmt + 1);
2283 case 'x':
2284 return pointer_string(buf, end, ptr, spec);
2285 case 'e':
2286 /* %pe with a non-ERR_PTR gets treated as plain %p */
2287 if (!IS_ERR(ptr))
2288 break;
2289 return err_ptr(buf, end, ptr, spec);
2290 case 'u':
2291 case 'k':
2292 switch (fmt[1]) {
2293 case 's':
2294 return string(buf, end, ptr, spec);
2295 default:
2296 return error_string(buf, end, "(einval)", spec);
2297 }
2298 }
2299
2300 /* default is to _not_ leak addresses, hash before printing */
2301 return ptr_to_id(buf, end, ptr, spec);
2302}
2303
2304/*
2305 * Helper function to decode printf style format.
2306 * Each call decode a token from the format and return the
2307 * number of characters read (or likely the delta where it wants
2308 * to go on the next call).
2309 * The decoded token is returned through the parameters
2310 *
2311 * 'h', 'l', or 'L' for integer fields
2312 * 'z' support added 23/7/1999 S.H.
2313 * 'z' changed to 'Z' --davidm 1/25/99
2314 * 'Z' changed to 'z' --adobriyan 2017-01-25
2315 * 't' added for ptrdiff_t
2316 *
2317 * @fmt: the format string
2318 * @type of the token returned
2319 * @flags: various flags such as +, -, # tokens..
2320 * @field_width: overwritten width
2321 * @base: base of the number (octal, hex, ...)
2322 * @precision: precision of a number
2323 * @qualifier: qualifier of a number (long, size_t, ...)
2324 */
2325static noinline_for_stack
2326int format_decode(const char *fmt, struct printf_spec *spec)
2327{
2328 const char *start = fmt;
2329 char qualifier;
2330
2331 /* we finished early by reading the field width */
2332 if (spec->type == FORMAT_TYPE_WIDTH) {
2333 if (spec->field_width < 0) {
2334 spec->field_width = -spec->field_width;
2335 spec->flags |= LEFT;
2336 }
2337 spec->type = FORMAT_TYPE_NONE;
2338 goto precision;
2339 }
2340
2341 /* we finished early by reading the precision */
2342 if (spec->type == FORMAT_TYPE_PRECISION) {
2343 if (spec->precision < 0)
2344 spec->precision = 0;
2345
2346 spec->type = FORMAT_TYPE_NONE;
2347 goto qualifier;
2348 }
2349
2350 /* By default */
2351 spec->type = FORMAT_TYPE_NONE;
2352
2353 for (; *fmt ; ++fmt) {
2354 if (*fmt == '%')
2355 break;
2356 }
2357
2358 /* Return the current non-format string */
2359 if (fmt != start || !*fmt)
2360 return fmt - start;
2361
2362 /* Process flags */
2363 spec->flags = 0;
2364
2365 while (1) { /* this also skips first '%' */
2366 bool found = true;
2367
2368 ++fmt;
2369
2370 switch (*fmt) {
2371 case '-': spec->flags |= LEFT; break;
2372 case '+': spec->flags |= PLUS; break;
2373 case ' ': spec->flags |= SPACE; break;
2374 case '#': spec->flags |= SPECIAL; break;
2375 case '0': spec->flags |= ZEROPAD; break;
2376 default: found = false;
2377 }
2378
2379 if (!found)
2380 break;
2381 }
2382
2383 /* get field width */
2384 spec->field_width = -1;
2385
2386 if (isdigit(*fmt))
2387 spec->field_width = skip_atoi(&fmt);
2388 else if (*fmt == '*') {
2389 /* it's the next argument */
2390 spec->type = FORMAT_TYPE_WIDTH;
2391 return ++fmt - start;
2392 }
2393
2394precision:
2395 /* get the precision */
2396 spec->precision = -1;
2397 if (*fmt == '.') {
2398 ++fmt;
2399 if (isdigit(*fmt)) {
2400 spec->precision = skip_atoi(&fmt);
2401 if (spec->precision < 0)
2402 spec->precision = 0;
2403 } else if (*fmt == '*') {
2404 /* it's the next argument */
2405 spec->type = FORMAT_TYPE_PRECISION;
2406 return ++fmt - start;
2407 }
2408 }
2409
2410qualifier:
2411 /* get the conversion qualifier */
2412 qualifier = 0;
2413 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2414 *fmt == 'z' || *fmt == 't') {
2415 qualifier = *fmt++;
2416 if (unlikely(qualifier == *fmt)) {
2417 if (qualifier == 'l') {
2418 qualifier = 'L';
2419 ++fmt;
2420 } else if (qualifier == 'h') {
2421 qualifier = 'H';
2422 ++fmt;
2423 }
2424 }
2425 }
2426
2427 /* default base */
2428 spec->base = 10;
2429 switch (*fmt) {
2430 case 'c':
2431 spec->type = FORMAT_TYPE_CHAR;
2432 return ++fmt - start;
2433
2434 case 's':
2435 spec->type = FORMAT_TYPE_STR;
2436 return ++fmt - start;
2437
2438 case 'p':
2439 spec->type = FORMAT_TYPE_PTR;
2440 return ++fmt - start;
2441
2442 case '%':
2443 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2444 return ++fmt - start;
2445
2446 /* integer number formats - set up the flags and "break" */
2447 case 'o':
2448 spec->base = 8;
2449 break;
2450
2451 case 'x':
2452 spec->flags |= SMALL;
2453 /* fall through */
2454
2455 case 'X':
2456 spec->base = 16;
2457 break;
2458
2459 case 'd':
2460 case 'i':
2461 spec->flags |= SIGN;
2462 case 'u':
2463 break;
2464
2465 case 'n':
2466 /*
2467 * Since %n poses a greater security risk than
2468 * utility, treat it as any other invalid or
2469 * unsupported format specifier.
2470 */
2471 /* fall through */
2472
2473 default:
2474 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2475 spec->type = FORMAT_TYPE_INVALID;
2476 return fmt - start;
2477 }
2478
2479 if (qualifier == 'L')
2480 spec->type = FORMAT_TYPE_LONG_LONG;
2481 else if (qualifier == 'l') {
2482 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2483 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2484 } else if (qualifier == 'z') {
2485 spec->type = FORMAT_TYPE_SIZE_T;
2486 } else if (qualifier == 't') {
2487 spec->type = FORMAT_TYPE_PTRDIFF;
2488 } else if (qualifier == 'H') {
2489 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2490 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2491 } else if (qualifier == 'h') {
2492 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2493 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2494 } else {
2495 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2496 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2497 }
2498
2499 return ++fmt - start;
2500}
2501
2502static void
2503set_field_width(struct printf_spec *spec, int width)
2504{
2505 spec->field_width = width;
2506 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2507 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2508 }
2509}
2510
2511static void
2512set_precision(struct printf_spec *spec, int prec)
2513{
2514 spec->precision = prec;
2515 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2516 spec->precision = clamp(prec, 0, PRECISION_MAX);
2517 }
2518}
2519
2520/**
2521 * vsnprintf - Format a string and place it in a buffer
2522 * @buf: The buffer to place the result into
2523 * @size: The size of the buffer, including the trailing null space
2524 * @fmt: The format string to use
2525 * @args: Arguments for the format string
2526 *
2527 * This function generally follows C99 vsnprintf, but has some
2528 * extensions and a few limitations:
2529 *
2530 * - ``%n`` is unsupported
2531 * - ``%p*`` is handled by pointer()
2532 *
2533 * See pointer() or Documentation/core-api/printk-formats.rst for more
2534 * extensive description.
2535 *
2536 * **Please update the documentation in both places when making changes**
2537 *
2538 * The return value is the number of characters which would
2539 * be generated for the given input, excluding the trailing
2540 * '\0', as per ISO C99. If you want to have the exact
2541 * number of characters written into @buf as return value
2542 * (not including the trailing '\0'), use vscnprintf(). If the
2543 * return is greater than or equal to @size, the resulting
2544 * string is truncated.
2545 *
2546 * If you're not already dealing with a va_list consider using snprintf().
2547 */
2548int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2549{
2550 unsigned long long num;
2551 char *str, *end;
2552 struct printf_spec spec = {0};
2553
2554 /* Reject out-of-range values early. Large positive sizes are
2555 used for unknown buffer sizes. */
2556 if (WARN_ON_ONCE(size > INT_MAX))
2557 return 0;
2558
2559 str = buf;
2560 end = buf + size;
2561
2562 /* Make sure end is always >= buf */
2563 if (end < buf) {
2564 end = ((void *)-1);
2565 size = end - buf;
2566 }
2567
2568 while (*fmt) {
2569 const char *old_fmt = fmt;
2570 int read = format_decode(fmt, &spec);
2571
2572 fmt += read;
2573
2574 switch (spec.type) {
2575 case FORMAT_TYPE_NONE: {
2576 int copy = read;
2577 if (str < end) {
2578 if (copy > end - str)
2579 copy = end - str;
2580 memcpy(str, old_fmt, copy);
2581 }
2582 str += read;
2583 break;
2584 }
2585
2586 case FORMAT_TYPE_WIDTH:
2587 set_field_width(&spec, va_arg(args, int));
2588 break;
2589
2590 case FORMAT_TYPE_PRECISION:
2591 set_precision(&spec, va_arg(args, int));
2592 break;
2593
2594 case FORMAT_TYPE_CHAR: {
2595 char c;
2596
2597 if (!(spec.flags & LEFT)) {
2598 while (--spec.field_width > 0) {
2599 if (str < end)
2600 *str = ' ';
2601 ++str;
2602
2603 }
2604 }
2605 c = (unsigned char) va_arg(args, int);
2606 if (str < end)
2607 *str = c;
2608 ++str;
2609 while (--spec.field_width > 0) {
2610 if (str < end)
2611 *str = ' ';
2612 ++str;
2613 }
2614 break;
2615 }
2616
2617 case FORMAT_TYPE_STR:
2618 str = string(str, end, va_arg(args, char *), spec);
2619 break;
2620
2621 case FORMAT_TYPE_PTR:
2622 str = pointer(fmt, str, end, va_arg(args, void *),
2623 spec);
2624 while (isalnum(*fmt))
2625 fmt++;
2626 break;
2627
2628 case FORMAT_TYPE_PERCENT_CHAR:
2629 if (str < end)
2630 *str = '%';
2631 ++str;
2632 break;
2633
2634 case FORMAT_TYPE_INVALID:
2635 /*
2636 * Presumably the arguments passed gcc's type
2637 * checking, but there is no safe or sane way
2638 * for us to continue parsing the format and
2639 * fetching from the va_list; the remaining
2640 * specifiers and arguments would be out of
2641 * sync.
2642 */
2643 goto out;
2644
2645 default:
2646 switch (spec.type) {
2647 case FORMAT_TYPE_LONG_LONG:
2648 num = va_arg(args, long long);
2649 break;
2650 case FORMAT_TYPE_ULONG:
2651 num = va_arg(args, unsigned long);
2652 break;
2653 case FORMAT_TYPE_LONG:
2654 num = va_arg(args, long);
2655 break;
2656 case FORMAT_TYPE_SIZE_T:
2657 if (spec.flags & SIGN)
2658 num = va_arg(args, ssize_t);
2659 else
2660 num = va_arg(args, size_t);
2661 break;
2662 case FORMAT_TYPE_PTRDIFF:
2663 num = va_arg(args, ptrdiff_t);
2664 break;
2665 case FORMAT_TYPE_UBYTE:
2666 num = (unsigned char) va_arg(args, int);
2667 break;
2668 case FORMAT_TYPE_BYTE:
2669 num = (signed char) va_arg(args, int);
2670 break;
2671 case FORMAT_TYPE_USHORT:
2672 num = (unsigned short) va_arg(args, int);
2673 break;
2674 case FORMAT_TYPE_SHORT:
2675 num = (short) va_arg(args, int);
2676 break;
2677 case FORMAT_TYPE_INT:
2678 num = (int) va_arg(args, int);
2679 break;
2680 default:
2681 num = va_arg(args, unsigned int);
2682 }
2683
2684 str = number(str, end, num, spec);
2685 }
2686 }
2687
2688out:
2689 if (size > 0) {
2690 if (str < end)
2691 *str = '\0';
2692 else
2693 end[-1] = '\0';
2694 }
2695
2696 /* the trailing null byte doesn't count towards the total */
2697 return str-buf;
2698
2699}
2700EXPORT_SYMBOL(vsnprintf);
2701
2702/**
2703 * vscnprintf - Format a string and place it in a buffer
2704 * @buf: The buffer to place the result into
2705 * @size: The size of the buffer, including the trailing null space
2706 * @fmt: The format string to use
2707 * @args: Arguments for the format string
2708 *
2709 * The return value is the number of characters which have been written into
2710 * the @buf not including the trailing '\0'. If @size is == 0 the function
2711 * returns 0.
2712 *
2713 * If you're not already dealing with a va_list consider using scnprintf().
2714 *
2715 * See the vsnprintf() documentation for format string extensions over C99.
2716 */
2717int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2718{
2719 int i;
2720
2721 i = vsnprintf(buf, size, fmt, args);
2722
2723 if (likely(i < size))
2724 return i;
2725 if (size != 0)
2726 return size - 1;
2727 return 0;
2728}
2729EXPORT_SYMBOL(vscnprintf);
2730
2731/**
2732 * snprintf - Format a string and place it in a buffer
2733 * @buf: The buffer to place the result into
2734 * @size: The size of the buffer, including the trailing null space
2735 * @fmt: The format string to use
2736 * @...: Arguments for the format string
2737 *
2738 * The return value is the number of characters which would be
2739 * generated for the given input, excluding the trailing null,
2740 * as per ISO C99. If the return is greater than or equal to
2741 * @size, the resulting string is truncated.
2742 *
2743 * See the vsnprintf() documentation for format string extensions over C99.
2744 */
2745int snprintf(char *buf, size_t size, const char *fmt, ...)
2746{
2747 va_list args;
2748 int i;
2749
2750 va_start(args, fmt);
2751 i = vsnprintf(buf, size, fmt, args);
2752 va_end(args);
2753
2754 return i;
2755}
2756EXPORT_SYMBOL(snprintf);
2757
2758/**
2759 * scnprintf - Format a string and place it in a buffer
2760 * @buf: The buffer to place the result into
2761 * @size: The size of the buffer, including the trailing null space
2762 * @fmt: The format string to use
2763 * @...: Arguments for the format string
2764 *
2765 * The return value is the number of characters written into @buf not including
2766 * the trailing '\0'. If @size is == 0 the function returns 0.
2767 */
2768
2769int scnprintf(char *buf, size_t size, const char *fmt, ...)
2770{
2771 va_list args;
2772 int i;
2773
2774 va_start(args, fmt);
2775 i = vscnprintf(buf, size, fmt, args);
2776 va_end(args);
2777
2778 return i;
2779}
2780EXPORT_SYMBOL(scnprintf);
2781
2782/**
2783 * vsprintf - Format a string and place it in a buffer
2784 * @buf: The buffer to place the result into
2785 * @fmt: The format string to use
2786 * @args: Arguments for the format string
2787 *
2788 * The function returns the number of characters written
2789 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2790 * buffer overflows.
2791 *
2792 * If you're not already dealing with a va_list consider using sprintf().
2793 *
2794 * See the vsnprintf() documentation for format string extensions over C99.
2795 */
2796int vsprintf(char *buf, const char *fmt, va_list args)
2797{
2798 return vsnprintf(buf, INT_MAX, fmt, args);
2799}
2800EXPORT_SYMBOL(vsprintf);
2801
2802/**
2803 * sprintf - Format a string and place it in a buffer
2804 * @buf: The buffer to place the result into
2805 * @fmt: The format string to use
2806 * @...: Arguments for the format string
2807 *
2808 * The function returns the number of characters written
2809 * into @buf. Use snprintf() or scnprintf() in order to avoid
2810 * buffer overflows.
2811 *
2812 * See the vsnprintf() documentation for format string extensions over C99.
2813 */
2814int sprintf(char *buf, const char *fmt, ...)
2815{
2816 va_list args;
2817 int i;
2818
2819 va_start(args, fmt);
2820 i = vsnprintf(buf, INT_MAX, fmt, args);
2821 va_end(args);
2822
2823 return i;
2824}
2825EXPORT_SYMBOL(sprintf);
2826
2827#ifdef CONFIG_BINARY_PRINTF
2828/*
2829 * bprintf service:
2830 * vbin_printf() - VA arguments to binary data
2831 * bstr_printf() - Binary data to text string
2832 */
2833
2834/**
2835 * vbin_printf - Parse a format string and place args' binary value in a buffer
2836 * @bin_buf: The buffer to place args' binary value
2837 * @size: The size of the buffer(by words(32bits), not characters)
2838 * @fmt: The format string to use
2839 * @args: Arguments for the format string
2840 *
2841 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2842 * is skipped.
2843 *
2844 * The return value is the number of words(32bits) which would be generated for
2845 * the given input.
2846 *
2847 * NOTE:
2848 * If the return value is greater than @size, the resulting bin_buf is NOT
2849 * valid for bstr_printf().
2850 */
2851int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2852{
2853 struct printf_spec spec = {0};
2854 char *str, *end;
2855 int width;
2856
2857 str = (char *)bin_buf;
2858 end = (char *)(bin_buf + size);
2859
2860#define save_arg(type) \
2861({ \
2862 unsigned long long value; \
2863 if (sizeof(type) == 8) { \
2864 unsigned long long val8; \
2865 str = PTR_ALIGN(str, sizeof(u32)); \
2866 val8 = va_arg(args, unsigned long long); \
2867 if (str + sizeof(type) <= end) { \
2868 *(u32 *)str = *(u32 *)&val8; \
2869 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
2870 } \
2871 value = val8; \
2872 } else { \
2873 unsigned int val4; \
2874 str = PTR_ALIGN(str, sizeof(type)); \
2875 val4 = va_arg(args, int); \
2876 if (str + sizeof(type) <= end) \
2877 *(typeof(type) *)str = (type)(long)val4; \
2878 value = (unsigned long long)val4; \
2879 } \
2880 str += sizeof(type); \
2881 value; \
2882})
2883
2884 while (*fmt) {
2885 int read = format_decode(fmt, &spec);
2886
2887 fmt += read;
2888
2889 switch (spec.type) {
2890 case FORMAT_TYPE_NONE:
2891 case FORMAT_TYPE_PERCENT_CHAR:
2892 break;
2893 case FORMAT_TYPE_INVALID:
2894 goto out;
2895
2896 case FORMAT_TYPE_WIDTH:
2897 case FORMAT_TYPE_PRECISION:
2898 width = (int)save_arg(int);
2899 /* Pointers may require the width */
2900 if (*fmt == 'p')
2901 set_field_width(&spec, width);
2902 break;
2903
2904 case FORMAT_TYPE_CHAR:
2905 save_arg(char);
2906 break;
2907
2908 case FORMAT_TYPE_STR: {
2909 const char *save_str = va_arg(args, char *);
2910 const char *err_msg;
2911 size_t len;
2912
2913 err_msg = check_pointer_msg(save_str);
2914 if (err_msg)
2915 save_str = err_msg;
2916
2917 len = strlen(save_str) + 1;
2918 if (str + len < end)
2919 memcpy(str, save_str, len);
2920 str += len;
2921 break;
2922 }
2923
2924 case FORMAT_TYPE_PTR:
2925 /* Dereferenced pointers must be done now */
2926 switch (*fmt) {
2927 /* Dereference of functions is still OK */
2928 case 'S':
2929 case 's':
2930 case 'x':
2931 case 'K':
2932 case 'e':
2933 save_arg(void *);
2934 break;
2935 default:
2936 if (!isalnum(*fmt)) {
2937 save_arg(void *);
2938 break;
2939 }
2940 str = pointer(fmt, str, end, va_arg(args, void *),
2941 spec);
2942 if (str + 1 < end)
2943 *str++ = '\0';
2944 else
2945 end[-1] = '\0'; /* Must be nul terminated */
2946 }
2947 /* skip all alphanumeric pointer suffixes */
2948 while (isalnum(*fmt))
2949 fmt++;
2950 break;
2951
2952 default:
2953 switch (spec.type) {
2954
2955 case FORMAT_TYPE_LONG_LONG:
2956 save_arg(long long);
2957 break;
2958 case FORMAT_TYPE_ULONG:
2959 case FORMAT_TYPE_LONG:
2960 save_arg(unsigned long);
2961 break;
2962 case FORMAT_TYPE_SIZE_T:
2963 save_arg(size_t);
2964 break;
2965 case FORMAT_TYPE_PTRDIFF:
2966 save_arg(ptrdiff_t);
2967 break;
2968 case FORMAT_TYPE_UBYTE:
2969 case FORMAT_TYPE_BYTE:
2970 save_arg(char);
2971 break;
2972 case FORMAT_TYPE_USHORT:
2973 case FORMAT_TYPE_SHORT:
2974 save_arg(short);
2975 break;
2976 default:
2977 save_arg(int);
2978 }
2979 }
2980 }
2981
2982out:
2983 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2984#undef save_arg
2985}
2986EXPORT_SYMBOL_GPL(vbin_printf);
2987
2988/**
2989 * bstr_printf - Format a string from binary arguments and place it in a buffer
2990 * @buf: The buffer to place the result into
2991 * @size: The size of the buffer, including the trailing null space
2992 * @fmt: The format string to use
2993 * @bin_buf: Binary arguments for the format string
2994 *
2995 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2996 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2997 * a binary buffer that generated by vbin_printf.
2998 *
2999 * The format follows C99 vsnprintf, but has some extensions:
3000 * see vsnprintf comment for details.
3001 *
3002 * The return value is the number of characters which would
3003 * be generated for the given input, excluding the trailing
3004 * '\0', as per ISO C99. If you want to have the exact
3005 * number of characters written into @buf as return value
3006 * (not including the trailing '\0'), use vscnprintf(). If the
3007 * return is greater than or equal to @size, the resulting
3008 * string is truncated.
3009 */
3010int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
3011{
3012 struct printf_spec spec = {0};
3013 char *str, *end;
3014 const char *args = (const char *)bin_buf;
3015
3016 if (WARN_ON_ONCE(size > INT_MAX))
3017 return 0;
3018
3019 str = buf;
3020 end = buf + size;
3021
3022#define get_arg(type) \
3023({ \
3024 typeof(type) value; \
3025 if (sizeof(type) == 8) { \
3026 args = PTR_ALIGN(args, sizeof(u32)); \
3027 *(u32 *)&value = *(u32 *)args; \
3028 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
3029 } else { \
3030 args = PTR_ALIGN(args, sizeof(type)); \
3031 value = *(typeof(type) *)args; \
3032 } \
3033 args += sizeof(type); \
3034 value; \
3035})
3036
3037 /* Make sure end is always >= buf */
3038 if (end < buf) {
3039 end = ((void *)-1);
3040 size = end - buf;
3041 }
3042
3043 while (*fmt) {
3044 const char *old_fmt = fmt;
3045 int read = format_decode(fmt, &spec);
3046
3047 fmt += read;
3048
3049 switch (spec.type) {
3050 case FORMAT_TYPE_NONE: {
3051 int copy = read;
3052 if (str < end) {
3053 if (copy > end - str)
3054 copy = end - str;
3055 memcpy(str, old_fmt, copy);
3056 }
3057 str += read;
3058 break;
3059 }
3060
3061 case FORMAT_TYPE_WIDTH:
3062 set_field_width(&spec, get_arg(int));
3063 break;
3064
3065 case FORMAT_TYPE_PRECISION:
3066 set_precision(&spec, get_arg(int));
3067 break;
3068
3069 case FORMAT_TYPE_CHAR: {
3070 char c;
3071
3072 if (!(spec.flags & LEFT)) {
3073 while (--spec.field_width > 0) {
3074 if (str < end)
3075 *str = ' ';
3076 ++str;
3077 }
3078 }
3079 c = (unsigned char) get_arg(char);
3080 if (str < end)
3081 *str = c;
3082 ++str;
3083 while (--spec.field_width > 0) {
3084 if (str < end)
3085 *str = ' ';
3086 ++str;
3087 }
3088 break;
3089 }
3090
3091 case FORMAT_TYPE_STR: {
3092 const char *str_arg = args;
3093 args += strlen(str_arg) + 1;
3094 str = string(str, end, (char *)str_arg, spec);
3095 break;
3096 }
3097
3098 case FORMAT_TYPE_PTR: {
3099 bool process = false;
3100 int copy, len;
3101 /* Non function dereferences were already done */
3102 switch (*fmt) {
3103 case 'S':
3104 case 's':
3105 case 'F':
3106 case 'f':
3107 case 'x':
3108 case 'K':
3109 case 'e':
3110 process = true;
3111 break;
3112 default:
3113 if (!isalnum(*fmt)) {
3114 process = true;
3115 break;
3116 }
3117 /* Pointer dereference was already processed */
3118 if (str < end) {
3119 len = copy = strlen(args);
3120 if (copy > end - str)
3121 copy = end - str;
3122 memcpy(str, args, copy);
3123 str += len;
3124 args += len + 1;
3125 }
3126 }
3127 if (process)
3128 str = pointer(fmt, str, end, get_arg(void *), spec);
3129
3130 while (isalnum(*fmt))
3131 fmt++;
3132 break;
3133 }
3134
3135 case FORMAT_TYPE_PERCENT_CHAR:
3136 if (str < end)
3137 *str = '%';
3138 ++str;
3139 break;
3140
3141 case FORMAT_TYPE_INVALID:
3142 goto out;
3143
3144 default: {
3145 unsigned long long num;
3146
3147 switch (spec.type) {
3148
3149 case FORMAT_TYPE_LONG_LONG:
3150 num = get_arg(long long);
3151 break;
3152 case FORMAT_TYPE_ULONG:
3153 case FORMAT_TYPE_LONG:
3154 num = get_arg(unsigned long);
3155 break;
3156 case FORMAT_TYPE_SIZE_T:
3157 num = get_arg(size_t);
3158 break;
3159 case FORMAT_TYPE_PTRDIFF:
3160 num = get_arg(ptrdiff_t);
3161 break;
3162 case FORMAT_TYPE_UBYTE:
3163 num = get_arg(unsigned char);
3164 break;
3165 case FORMAT_TYPE_BYTE:
3166 num = get_arg(signed char);
3167 break;
3168 case FORMAT_TYPE_USHORT:
3169 num = get_arg(unsigned short);
3170 break;
3171 case FORMAT_TYPE_SHORT:
3172 num = get_arg(short);
3173 break;
3174 case FORMAT_TYPE_UINT:
3175 num = get_arg(unsigned int);
3176 break;
3177 default:
3178 num = get_arg(int);
3179 }
3180
3181 str = number(str, end, num, spec);
3182 } /* default: */
3183 } /* switch(spec.type) */
3184 } /* while(*fmt) */
3185
3186out:
3187 if (size > 0) {
3188 if (str < end)
3189 *str = '\0';
3190 else
3191 end[-1] = '\0';
3192 }
3193
3194#undef get_arg
3195
3196 /* the trailing null byte doesn't count towards the total */
3197 return str - buf;
3198}
3199EXPORT_SYMBOL_GPL(bstr_printf);
3200
3201/**
3202 * bprintf - Parse a format string and place args' binary value in a buffer
3203 * @bin_buf: The buffer to place args' binary value
3204 * @size: The size of the buffer(by words(32bits), not characters)
3205 * @fmt: The format string to use
3206 * @...: Arguments for the format string
3207 *
3208 * The function returns the number of words(u32) written
3209 * into @bin_buf.
3210 */
3211int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3212{
3213 va_list args;
3214 int ret;
3215
3216 va_start(args, fmt);
3217 ret = vbin_printf(bin_buf, size, fmt, args);
3218 va_end(args);
3219
3220 return ret;
3221}
3222EXPORT_SYMBOL_GPL(bprintf);
3223
3224#endif /* CONFIG_BINARY_PRINTF */
3225
3226/**
3227 * vsscanf - Unformat a buffer into a list of arguments
3228 * @buf: input buffer
3229 * @fmt: format of buffer
3230 * @args: arguments
3231 */
3232int vsscanf(const char *buf, const char *fmt, va_list args)
3233{
3234 const char *str = buf;
3235 char *next;
3236 char digit;
3237 int num = 0;
3238 u8 qualifier;
3239 unsigned int base;
3240 union {
3241 long long s;
3242 unsigned long long u;
3243 } val;
3244 s16 field_width;
3245 bool is_sign;
3246
3247 while (*fmt) {
3248 /* skip any white space in format */
3249 /* white space in format matchs any amount of
3250 * white space, including none, in the input.
3251 */
3252 if (isspace(*fmt)) {
3253 fmt = skip_spaces(++fmt);
3254 str = skip_spaces(str);
3255 }
3256
3257 /* anything that is not a conversion must match exactly */
3258 if (*fmt != '%' && *fmt) {
3259 if (*fmt++ != *str++)
3260 break;
3261 continue;
3262 }
3263
3264 if (!*fmt)
3265 break;
3266 ++fmt;
3267
3268 /* skip this conversion.
3269 * advance both strings to next white space
3270 */
3271 if (*fmt == '*') {
3272 if (!*str)
3273 break;
3274 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3275 /* '%*[' not yet supported, invalid format */
3276 if (*fmt == '[')
3277 return num;
3278 fmt++;
3279 }
3280 while (!isspace(*str) && *str)
3281 str++;
3282 continue;
3283 }
3284
3285 /* get field width */
3286 field_width = -1;
3287 if (isdigit(*fmt)) {
3288 field_width = skip_atoi(&fmt);
3289 if (field_width <= 0)
3290 break;
3291 }
3292
3293 /* get conversion qualifier */
3294 qualifier = -1;
3295 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3296 *fmt == 'z') {
3297 qualifier = *fmt++;
3298 if (unlikely(qualifier == *fmt)) {
3299 if (qualifier == 'h') {
3300 qualifier = 'H';
3301 fmt++;
3302 } else if (qualifier == 'l') {
3303 qualifier = 'L';
3304 fmt++;
3305 }
3306 }
3307 }
3308
3309 if (!*fmt)
3310 break;
3311
3312 if (*fmt == 'n') {
3313 /* return number of characters read so far */
3314 *va_arg(args, int *) = str - buf;
3315 ++fmt;
3316 continue;
3317 }
3318
3319 if (!*str)
3320 break;
3321
3322 base = 10;
3323 is_sign = false;
3324
3325 switch (*fmt++) {
3326 case 'c':
3327 {
3328 char *s = (char *)va_arg(args, char*);
3329 if (field_width == -1)
3330 field_width = 1;
3331 do {
3332 *s++ = *str++;
3333 } while (--field_width > 0 && *str);
3334 num++;
3335 }
3336 continue;
3337 case 's':
3338 {
3339 char *s = (char *)va_arg(args, char *);
3340 if (field_width == -1)
3341 field_width = SHRT_MAX;
3342 /* first, skip leading white space in buffer */
3343 str = skip_spaces(str);
3344
3345 /* now copy until next white space */
3346 while (*str && !isspace(*str) && field_width--)
3347 *s++ = *str++;
3348 *s = '\0';
3349 num++;
3350 }
3351 continue;
3352 /*
3353 * Warning: This implementation of the '[' conversion specifier
3354 * deviates from its glibc counterpart in the following ways:
3355 * (1) It does NOT support ranges i.e. '-' is NOT a special
3356 * character
3357 * (2) It cannot match the closing bracket ']' itself
3358 * (3) A field width is required
3359 * (4) '%*[' (discard matching input) is currently not supported
3360 *
3361 * Example usage:
3362 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3363 * buf1, buf2, buf3);
3364 * if (ret < 3)
3365 * // etc..
3366 */
3367 case '[':
3368 {
3369 char *s = (char *)va_arg(args, char *);
3370 DECLARE_BITMAP(set, 256) = {0};
3371 unsigned int len = 0;
3372 bool negate = (*fmt == '^');
3373
3374 /* field width is required */
3375 if (field_width == -1)
3376 return num;
3377
3378 if (negate)
3379 ++fmt;
3380
3381 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3382 set_bit((u8)*fmt, set);
3383
3384 /* no ']' or no character set found */
3385 if (!*fmt || !len)
3386 return num;
3387 ++fmt;
3388
3389 if (negate) {
3390 bitmap_complement(set, set, 256);
3391 /* exclude null '\0' byte */
3392 clear_bit(0, set);
3393 }
3394
3395 /* match must be non-empty */
3396 if (!test_bit((u8)*str, set))
3397 return num;
3398
3399 while (test_bit((u8)*str, set) && field_width--)
3400 *s++ = *str++;
3401 *s = '\0';
3402 ++num;
3403 }
3404 continue;
3405 case 'o':
3406 base = 8;
3407 break;
3408 case 'x':
3409 case 'X':
3410 base = 16;
3411 break;
3412 case 'i':
3413 base = 0;
3414 /* fall through */
3415 case 'd':
3416 is_sign = true;
3417 /* fall through */
3418 case 'u':
3419 break;
3420 case '%':
3421 /* looking for '%' in str */
3422 if (*str++ != '%')
3423 return num;
3424 continue;
3425 default:
3426 /* invalid format; stop here */
3427 return num;
3428 }
3429
3430 /* have some sort of integer conversion.
3431 * first, skip white space in buffer.
3432 */
3433 str = skip_spaces(str);
3434
3435 digit = *str;
3436 if (is_sign && digit == '-')
3437 digit = *(str + 1);
3438
3439 if (!digit
3440 || (base == 16 && !isxdigit(digit))
3441 || (base == 10 && !isdigit(digit))
3442 || (base == 8 && (!isdigit(digit) || digit > '7'))
3443 || (base == 0 && !isdigit(digit)))
3444 break;
3445
3446 if (is_sign)
3447 val.s = qualifier != 'L' ?
3448 simple_strtol(str, &next, base) :
3449 simple_strtoll(str, &next, base);
3450 else
3451 val.u = qualifier != 'L' ?
3452 simple_strtoul(str, &next, base) :
3453 simple_strtoull(str, &next, base);
3454
3455 if (field_width > 0 && next - str > field_width) {
3456 if (base == 0)
3457 _parse_integer_fixup_radix(str, &base);
3458 while (next - str > field_width) {
3459 if (is_sign)
3460 val.s = div_s64(val.s, base);
3461 else
3462 val.u = div_u64(val.u, base);
3463 --next;
3464 }
3465 }
3466
3467 switch (qualifier) {
3468 case 'H': /* that's 'hh' in format */
3469 if (is_sign)
3470 *va_arg(args, signed char *) = val.s;
3471 else
3472 *va_arg(args, unsigned char *) = val.u;
3473 break;
3474 case 'h':
3475 if (is_sign)
3476 *va_arg(args, short *) = val.s;
3477 else
3478 *va_arg(args, unsigned short *) = val.u;
3479 break;
3480 case 'l':
3481 if (is_sign)
3482 *va_arg(args, long *) = val.s;
3483 else
3484 *va_arg(args, unsigned long *) = val.u;
3485 break;
3486 case 'L':
3487 if (is_sign)
3488 *va_arg(args, long long *) = val.s;
3489 else
3490 *va_arg(args, unsigned long long *) = val.u;
3491 break;
3492 case 'z':
3493 *va_arg(args, size_t *) = val.u;
3494 break;
3495 default:
3496 if (is_sign)
3497 *va_arg(args, int *) = val.s;
3498 else
3499 *va_arg(args, unsigned int *) = val.u;
3500 break;
3501 }
3502 num++;
3503
3504 if (!next)
3505 break;
3506 str = next;
3507 }
3508
3509 return num;
3510}
3511EXPORT_SYMBOL(vsscanf);
3512
3513/**
3514 * sscanf - Unformat a buffer into a list of arguments
3515 * @buf: input buffer
3516 * @fmt: formatting of buffer
3517 * @...: resulting arguments
3518 */
3519int sscanf(const char *buf, const char *fmt, ...)
3520{
3521 va_list args;
3522 int i;
3523
3524 va_start(args, fmt);
3525 i = vsscanf(buf, fmt, args);
3526 va_end(args);
3527
3528 return i;
3529}
3530EXPORT_SYMBOL(sscanf);