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56 * This function is obsolete.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81 * This function is obsolete.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95 * This function is obsolete.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