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[thirdparty/linux.git] / lib / vsprintf.c
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 */
64 unsigned 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 }
79 EXPORT_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 */
89 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
90 {
91 return simple_strtoull(cp, endp, base);
92 }
93 EXPORT_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 */
103 long 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 }
110 EXPORT_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 */
120 long 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 }
127 EXPORT_SYMBOL(simple_strtoll);
128
129 static noinline_for_stack
130 int 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
166 static 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 */
187 static noinline_for_stack
188 char *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;
218 out_q:
219 /* 1 <= q < 100 */
220 r = q;
221 out_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
229 static noinline_for_stack
230 char *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
255 static noinline_for_stack
256 char *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
269 static void
270 put_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 */
289 static noinline_for_stack
290 unsigned 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 */
303 static
304 char *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 */
345 int 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
384 enum format_type {
385 FORMAT_TYPE_NONE, /* Just a string part */
386 FORMAT_TYPE_WIDTH,
387 FORMAT_TYPE_PRECISION,
388 FORMAT_TYPE_CHAR,
389 FORMAT_TYPE_STR,
390 FORMAT_TYPE_PTR,
391 FORMAT_TYPE_PERCENT_CHAR,
392 FORMAT_TYPE_INVALID,
393 FORMAT_TYPE_LONG_LONG,
394 FORMAT_TYPE_ULONG,
395 FORMAT_TYPE_LONG,
396 FORMAT_TYPE_UBYTE,
397 FORMAT_TYPE_BYTE,
398 FORMAT_TYPE_USHORT,
399 FORMAT_TYPE_SHORT,
400 FORMAT_TYPE_UINT,
401 FORMAT_TYPE_INT,
402 FORMAT_TYPE_SIZE_T,
403 FORMAT_TYPE_PTRDIFF
404 };
405
406 struct printf_spec {
407 unsigned int type:8; /* format_type enum */
408 signed int field_width:24; /* width of output field */
409 unsigned int flags:8; /* flags to number() */
410 unsigned int base:8; /* number base, 8, 10 or 16 only */
411 signed int precision:16; /* # of digits/chars */
412 } __packed;
413 static_assert(sizeof(struct printf_spec) == 8);
414
415 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
416 #define PRECISION_MAX ((1 << 15) - 1)
417
418 static noinline_for_stack
419 char *number(char *buf, char *end, unsigned long long num,
420 struct printf_spec spec)
421 {
422 /* put_dec requires 2-byte alignment of the buffer. */
423 char tmp[3 * sizeof(num)] __aligned(2);
424 char sign;
425 char locase;
426 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
427 int i;
428 bool is_zero = num == 0LL;
429 int field_width = spec.field_width;
430 int precision = spec.precision;
431
432 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
433 * produces same digits or (maybe lowercased) letters */
434 locase = (spec.flags & SMALL);
435 if (spec.flags & LEFT)
436 spec.flags &= ~ZEROPAD;
437 sign = 0;
438 if (spec.flags & SIGN) {
439 if ((signed long long)num < 0) {
440 sign = '-';
441 num = -(signed long long)num;
442 field_width--;
443 } else if (spec.flags & PLUS) {
444 sign = '+';
445 field_width--;
446 } else if (spec.flags & SPACE) {
447 sign = ' ';
448 field_width--;
449 }
450 }
451 if (need_pfx) {
452 if (spec.base == 16)
453 field_width -= 2;
454 else if (!is_zero)
455 field_width--;
456 }
457
458 /* generate full string in tmp[], in reverse order */
459 i = 0;
460 if (num < spec.base)
461 tmp[i++] = hex_asc_upper[num] | locase;
462 else if (spec.base != 10) { /* 8 or 16 */
463 int mask = spec.base - 1;
464 int shift = 3;
465
466 if (spec.base == 16)
467 shift = 4;
468 do {
469 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
470 num >>= shift;
471 } while (num);
472 } else { /* base 10 */
473 i = put_dec(tmp, num) - tmp;
474 }
475
476 /* printing 100 using %2d gives "100", not "00" */
477 if (i > precision)
478 precision = i;
479 /* leading space padding */
480 field_width -= precision;
481 if (!(spec.flags & (ZEROPAD | LEFT))) {
482 while (--field_width >= 0) {
483 if (buf < end)
484 *buf = ' ';
485 ++buf;
486 }
487 }
488 /* sign */
489 if (sign) {
490 if (buf < end)
491 *buf = sign;
492 ++buf;
493 }
494 /* "0x" / "0" prefix */
495 if (need_pfx) {
496 if (spec.base == 16 || !is_zero) {
497 if (buf < end)
498 *buf = '0';
499 ++buf;
500 }
501 if (spec.base == 16) {
502 if (buf < end)
503 *buf = ('X' | locase);
504 ++buf;
505 }
506 }
507 /* zero or space padding */
508 if (!(spec.flags & LEFT)) {
509 char c = ' ' + (spec.flags & ZEROPAD);
510 BUILD_BUG_ON(' ' + ZEROPAD != '0');
511 while (--field_width >= 0) {
512 if (buf < end)
513 *buf = c;
514 ++buf;
515 }
516 }
517 /* hmm even more zero padding? */
518 while (i <= --precision) {
519 if (buf < end)
520 *buf = '0';
521 ++buf;
522 }
523 /* actual digits of result */
524 while (--i >= 0) {
525 if (buf < end)
526 *buf = tmp[i];
527 ++buf;
528 }
529 /* trailing space padding */
530 while (--field_width >= 0) {
531 if (buf < end)
532 *buf = ' ';
533 ++buf;
534 }
535
536 return buf;
537 }
538
539 static noinline_for_stack
540 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
541 {
542 struct printf_spec spec;
543
544 spec.type = FORMAT_TYPE_PTR;
545 spec.field_width = 2 + 2 * size; /* 0x + hex */
546 spec.flags = SPECIAL | SMALL | ZEROPAD;
547 spec.base = 16;
548 spec.precision = -1;
549
550 return number(buf, end, num, spec);
551 }
552
553 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
554 {
555 size_t size;
556 if (buf >= end) /* nowhere to put anything */
557 return;
558 size = end - buf;
559 if (size <= spaces) {
560 memset(buf, ' ', size);
561 return;
562 }
563 if (len) {
564 if (len > size - spaces)
565 len = size - spaces;
566 memmove(buf + spaces, buf, len);
567 }
568 memset(buf, ' ', spaces);
569 }
570
571 /*
572 * Handle field width padding for a string.
573 * @buf: current buffer position
574 * @n: length of string
575 * @end: end of output buffer
576 * @spec: for field width and flags
577 * Returns: new buffer position after padding.
578 */
579 static noinline_for_stack
580 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
581 {
582 unsigned spaces;
583
584 if (likely(n >= spec.field_width))
585 return buf;
586 /* we want to pad the sucker */
587 spaces = spec.field_width - n;
588 if (!(spec.flags & LEFT)) {
589 move_right(buf - n, end, n, spaces);
590 return buf + spaces;
591 }
592 while (spaces--) {
593 if (buf < end)
594 *buf = ' ';
595 ++buf;
596 }
597 return buf;
598 }
599
600 /* Handle string from a well known address. */
601 static char *string_nocheck(char *buf, char *end, const char *s,
602 struct printf_spec spec)
603 {
604 int len = 0;
605 int lim = spec.precision;
606
607 while (lim--) {
608 char c = *s++;
609 if (!c)
610 break;
611 if (buf < end)
612 *buf = c;
613 ++buf;
614 ++len;
615 }
616 return widen_string(buf, len, end, spec);
617 }
618
619 static char *err_ptr(char *buf, char *end, void *ptr,
620 struct printf_spec spec)
621 {
622 int err = PTR_ERR(ptr);
623 const char *sym = errname(err);
624
625 if (sym)
626 return string_nocheck(buf, end, sym, spec);
627
628 /*
629 * Somebody passed ERR_PTR(-1234) or some other non-existing
630 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to
631 * printing it as its decimal representation.
632 */
633 spec.flags |= SIGN;
634 spec.base = 10;
635 return number(buf, end, err, spec);
636 }
637
638 /* Be careful: error messages must fit into the given buffer. */
639 static char *error_string(char *buf, char *end, const char *s,
640 struct printf_spec spec)
641 {
642 /*
643 * Hard limit to avoid a completely insane messages. It actually
644 * works pretty well because most error messages are in
645 * the many pointer format modifiers.
646 */
647 if (spec.precision == -1)
648 spec.precision = 2 * sizeof(void *);
649
650 return string_nocheck(buf, end, s, spec);
651 }
652
653 /*
654 * Do not call any complex external code here. Nested printk()/vsprintf()
655 * might cause infinite loops. Failures might break printk() and would
656 * be hard to debug.
657 */
658 static const char *check_pointer_msg(const void *ptr)
659 {
660 if (!ptr)
661 return "(null)";
662
663 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
664 return "(efault)";
665
666 return NULL;
667 }
668
669 static int check_pointer(char **buf, char *end, const void *ptr,
670 struct printf_spec spec)
671 {
672 const char *err_msg;
673
674 err_msg = check_pointer_msg(ptr);
675 if (err_msg) {
676 *buf = error_string(*buf, end, err_msg, spec);
677 return -EFAULT;
678 }
679
680 return 0;
681 }
682
683 static noinline_for_stack
684 char *string(char *buf, char *end, const char *s,
685 struct printf_spec spec)
686 {
687 if (check_pointer(&buf, end, s, spec))
688 return buf;
689
690 return string_nocheck(buf, end, s, spec);
691 }
692
693 static char *pointer_string(char *buf, char *end,
694 const void *ptr,
695 struct printf_spec spec)
696 {
697 spec.base = 16;
698 spec.flags |= SMALL;
699 if (spec.field_width == -1) {
700 spec.field_width = 2 * sizeof(ptr);
701 spec.flags |= ZEROPAD;
702 }
703
704 return number(buf, end, (unsigned long int)ptr, spec);
705 }
706
707 /* Make pointers available for printing early in the boot sequence. */
708 static int debug_boot_weak_hash __ro_after_init;
709
710 static int __init debug_boot_weak_hash_enable(char *str)
711 {
712 debug_boot_weak_hash = 1;
713 pr_info("debug_boot_weak_hash enabled\n");
714 return 0;
715 }
716 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
717
718 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
719 static siphash_key_t ptr_key __read_mostly;
720
721 static void enable_ptr_key_workfn(struct work_struct *work)
722 {
723 get_random_bytes(&ptr_key, sizeof(ptr_key));
724 /* Needs to run from preemptible context */
725 static_branch_disable(&not_filled_random_ptr_key);
726 }
727
728 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
729
730 static void fill_random_ptr_key(struct random_ready_callback *unused)
731 {
732 /* This may be in an interrupt handler. */
733 queue_work(system_unbound_wq, &enable_ptr_key_work);
734 }
735
736 static struct random_ready_callback random_ready = {
737 .func = fill_random_ptr_key
738 };
739
740 static int __init initialize_ptr_random(void)
741 {
742 int key_size = sizeof(ptr_key);
743 int ret;
744
745 /* Use hw RNG if available. */
746 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
747 static_branch_disable(&not_filled_random_ptr_key);
748 return 0;
749 }
750
751 ret = add_random_ready_callback(&random_ready);
752 if (!ret) {
753 return 0;
754 } else if (ret == -EALREADY) {
755 /* This is in preemptible context */
756 enable_ptr_key_workfn(&enable_ptr_key_work);
757 return 0;
758 }
759
760 return ret;
761 }
762 early_initcall(initialize_ptr_random);
763
764 /* Maps a pointer to a 32 bit unique identifier. */
765 static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
766 {
767 unsigned long hashval;
768
769 if (static_branch_unlikely(&not_filled_random_ptr_key))
770 return -EAGAIN;
771
772 #ifdef CONFIG_64BIT
773 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
774 /*
775 * Mask off the first 32 bits, this makes explicit that we have
776 * modified the address (and 32 bits is plenty for a unique ID).
777 */
778 hashval = hashval & 0xffffffff;
779 #else
780 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
781 #endif
782 *hashval_out = hashval;
783 return 0;
784 }
785
786 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
787 {
788 return __ptr_to_hashval(ptr, hashval_out);
789 }
790
791 static char *ptr_to_id(char *buf, char *end, const void *ptr,
792 struct printf_spec spec)
793 {
794 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
795 unsigned long hashval;
796 int ret;
797
798 /*
799 * Print the real pointer value for NULL and error pointers,
800 * as they are not actual addresses.
801 */
802 if (IS_ERR_OR_NULL(ptr))
803 return pointer_string(buf, end, ptr, spec);
804
805 /* When debugging early boot use non-cryptographically secure hash. */
806 if (unlikely(debug_boot_weak_hash)) {
807 hashval = hash_long((unsigned long)ptr, 32);
808 return pointer_string(buf, end, (const void *)hashval, spec);
809 }
810
811 ret = __ptr_to_hashval(ptr, &hashval);
812 if (ret) {
813 spec.field_width = 2 * sizeof(ptr);
814 /* string length must be less than default_width */
815 return error_string(buf, end, str, spec);
816 }
817
818 return pointer_string(buf, end, (const void *)hashval, spec);
819 }
820
821 int kptr_restrict __read_mostly;
822
823 static noinline_for_stack
824 char *restricted_pointer(char *buf, char *end, const void *ptr,
825 struct printf_spec spec)
826 {
827 switch (kptr_restrict) {
828 case 0:
829 /* Handle as %p, hash and do _not_ leak addresses. */
830 return ptr_to_id(buf, end, ptr, spec);
831 case 1: {
832 const struct cred *cred;
833
834 /*
835 * kptr_restrict==1 cannot be used in IRQ context
836 * because its test for CAP_SYSLOG would be meaningless.
837 */
838 if (in_irq() || in_serving_softirq() || in_nmi()) {
839 if (spec.field_width == -1)
840 spec.field_width = 2 * sizeof(ptr);
841 return error_string(buf, end, "pK-error", spec);
842 }
843
844 /*
845 * Only print the real pointer value if the current
846 * process has CAP_SYSLOG and is running with the
847 * same credentials it started with. This is because
848 * access to files is checked at open() time, but %pK
849 * checks permission at read() time. We don't want to
850 * leak pointer values if a binary opens a file using
851 * %pK and then elevates privileges before reading it.
852 */
853 cred = current_cred();
854 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
855 !uid_eq(cred->euid, cred->uid) ||
856 !gid_eq(cred->egid, cred->gid))
857 ptr = NULL;
858 break;
859 }
860 case 2:
861 default:
862 /* Always print 0's for %pK */
863 ptr = NULL;
864 break;
865 }
866
867 return pointer_string(buf, end, ptr, spec);
868 }
869
870 static noinline_for_stack
871 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
872 const char *fmt)
873 {
874 const char *array[4], *s;
875 const struct dentry *p;
876 int depth;
877 int i, n;
878
879 switch (fmt[1]) {
880 case '2': case '3': case '4':
881 depth = fmt[1] - '0';
882 break;
883 default:
884 depth = 1;
885 }
886
887 rcu_read_lock();
888 for (i = 0; i < depth; i++, d = p) {
889 if (check_pointer(&buf, end, d, spec)) {
890 rcu_read_unlock();
891 return buf;
892 }
893
894 p = READ_ONCE(d->d_parent);
895 array[i] = READ_ONCE(d->d_name.name);
896 if (p == d) {
897 if (i)
898 array[i] = "";
899 i++;
900 break;
901 }
902 }
903 s = array[--i];
904 for (n = 0; n != spec.precision; n++, buf++) {
905 char c = *s++;
906 if (!c) {
907 if (!i)
908 break;
909 c = '/';
910 s = array[--i];
911 }
912 if (buf < end)
913 *buf = c;
914 }
915 rcu_read_unlock();
916 return widen_string(buf, n, end, spec);
917 }
918
919 static noinline_for_stack
920 char *file_dentry_name(char *buf, char *end, const struct file *f,
921 struct printf_spec spec, const char *fmt)
922 {
923 if (check_pointer(&buf, end, f, spec))
924 return buf;
925
926 return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
927 }
928 #ifdef CONFIG_BLOCK
929 static noinline_for_stack
930 char *bdev_name(char *buf, char *end, struct block_device *bdev,
931 struct printf_spec spec, const char *fmt)
932 {
933 struct gendisk *hd;
934
935 if (check_pointer(&buf, end, bdev, spec))
936 return buf;
937
938 hd = bdev->bd_disk;
939 buf = string(buf, end, hd->disk_name, spec);
940 if (bdev->bd_part->partno) {
941 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
942 if (buf < end)
943 *buf = 'p';
944 buf++;
945 }
946 buf = number(buf, end, bdev->bd_part->partno, spec);
947 }
948 return buf;
949 }
950 #endif
951
952 static noinline_for_stack
953 char *symbol_string(char *buf, char *end, void *ptr,
954 struct printf_spec spec, const char *fmt)
955 {
956 unsigned long value;
957 #ifdef CONFIG_KALLSYMS
958 char sym[KSYM_SYMBOL_LEN];
959 #endif
960
961 if (fmt[1] == 'R')
962 ptr = __builtin_extract_return_addr(ptr);
963 value = (unsigned long)ptr;
964
965 #ifdef CONFIG_KALLSYMS
966 if (*fmt == 'B')
967 sprint_backtrace(sym, value);
968 else if (*fmt != 's')
969 sprint_symbol(sym, value);
970 else
971 sprint_symbol_no_offset(sym, value);
972
973 return string_nocheck(buf, end, sym, spec);
974 #else
975 return special_hex_number(buf, end, value, sizeof(void *));
976 #endif
977 }
978
979 static const struct printf_spec default_str_spec = {
980 .field_width = -1,
981 .precision = -1,
982 };
983
984 static const struct printf_spec default_flag_spec = {
985 .base = 16,
986 .precision = -1,
987 .flags = SPECIAL | SMALL,
988 };
989
990 static const struct printf_spec default_dec_spec = {
991 .base = 10,
992 .precision = -1,
993 };
994
995 static const struct printf_spec default_dec02_spec = {
996 .base = 10,
997 .field_width = 2,
998 .precision = -1,
999 .flags = ZEROPAD,
1000 };
1001
1002 static const struct printf_spec default_dec04_spec = {
1003 .base = 10,
1004 .field_width = 4,
1005 .precision = -1,
1006 .flags = ZEROPAD,
1007 };
1008
1009 static noinline_for_stack
1010 char *resource_string(char *buf, char *end, struct resource *res,
1011 struct printf_spec spec, const char *fmt)
1012 {
1013 #ifndef IO_RSRC_PRINTK_SIZE
1014 #define IO_RSRC_PRINTK_SIZE 6
1015 #endif
1016
1017 #ifndef MEM_RSRC_PRINTK_SIZE
1018 #define MEM_RSRC_PRINTK_SIZE 10
1019 #endif
1020 static const struct printf_spec io_spec = {
1021 .base = 16,
1022 .field_width = IO_RSRC_PRINTK_SIZE,
1023 .precision = -1,
1024 .flags = SPECIAL | SMALL | ZEROPAD,
1025 };
1026 static const struct printf_spec mem_spec = {
1027 .base = 16,
1028 .field_width = MEM_RSRC_PRINTK_SIZE,
1029 .precision = -1,
1030 .flags = SPECIAL | SMALL | ZEROPAD,
1031 };
1032 static const struct printf_spec bus_spec = {
1033 .base = 16,
1034 .field_width = 2,
1035 .precision = -1,
1036 .flags = SMALL | ZEROPAD,
1037 };
1038 static const struct printf_spec str_spec = {
1039 .field_width = -1,
1040 .precision = 10,
1041 .flags = LEFT,
1042 };
1043
1044 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
1045 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
1046 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
1047 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
1048 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
1049 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
1050 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
1051 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
1052
1053 char *p = sym, *pend = sym + sizeof(sym);
1054 int decode = (fmt[0] == 'R') ? 1 : 0;
1055 const struct printf_spec *specp;
1056
1057 if (check_pointer(&buf, end, res, spec))
1058 return buf;
1059
1060 *p++ = '[';
1061 if (res->flags & IORESOURCE_IO) {
1062 p = string_nocheck(p, pend, "io ", str_spec);
1063 specp = &io_spec;
1064 } else if (res->flags & IORESOURCE_MEM) {
1065 p = string_nocheck(p, pend, "mem ", str_spec);
1066 specp = &mem_spec;
1067 } else if (res->flags & IORESOURCE_IRQ) {
1068 p = string_nocheck(p, pend, "irq ", str_spec);
1069 specp = &default_dec_spec;
1070 } else if (res->flags & IORESOURCE_DMA) {
1071 p = string_nocheck(p, pend, "dma ", str_spec);
1072 specp = &default_dec_spec;
1073 } else if (res->flags & IORESOURCE_BUS) {
1074 p = string_nocheck(p, pend, "bus ", str_spec);
1075 specp = &bus_spec;
1076 } else {
1077 p = string_nocheck(p, pend, "??? ", str_spec);
1078 specp = &mem_spec;
1079 decode = 0;
1080 }
1081 if (decode && res->flags & IORESOURCE_UNSET) {
1082 p = string_nocheck(p, pend, "size ", str_spec);
1083 p = number(p, pend, resource_size(res), *specp);
1084 } else {
1085 p = number(p, pend, res->start, *specp);
1086 if (res->start != res->end) {
1087 *p++ = '-';
1088 p = number(p, pend, res->end, *specp);
1089 }
1090 }
1091 if (decode) {
1092 if (res->flags & IORESOURCE_MEM_64)
1093 p = string_nocheck(p, pend, " 64bit", str_spec);
1094 if (res->flags & IORESOURCE_PREFETCH)
1095 p = string_nocheck(p, pend, " pref", str_spec);
1096 if (res->flags & IORESOURCE_WINDOW)
1097 p = string_nocheck(p, pend, " window", str_spec);
1098 if (res->flags & IORESOURCE_DISABLED)
1099 p = string_nocheck(p, pend, " disabled", str_spec);
1100 } else {
1101 p = string_nocheck(p, pend, " flags ", str_spec);
1102 p = number(p, pend, res->flags, default_flag_spec);
1103 }
1104 *p++ = ']';
1105 *p = '\0';
1106
1107 return string_nocheck(buf, end, sym, spec);
1108 }
1109
1110 static noinline_for_stack
1111 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1112 const char *fmt)
1113 {
1114 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
1115 negative value, fallback to the default */
1116 char separator;
1117
1118 if (spec.field_width == 0)
1119 /* nothing to print */
1120 return buf;
1121
1122 if (check_pointer(&buf, end, addr, spec))
1123 return buf;
1124
1125 switch (fmt[1]) {
1126 case 'C':
1127 separator = ':';
1128 break;
1129 case 'D':
1130 separator = '-';
1131 break;
1132 case 'N':
1133 separator = 0;
1134 break;
1135 default:
1136 separator = ' ';
1137 break;
1138 }
1139
1140 if (spec.field_width > 0)
1141 len = min_t(int, spec.field_width, 64);
1142
1143 for (i = 0; i < len; ++i) {
1144 if (buf < end)
1145 *buf = hex_asc_hi(addr[i]);
1146 ++buf;
1147 if (buf < end)
1148 *buf = hex_asc_lo(addr[i]);
1149 ++buf;
1150
1151 if (separator && i != len - 1) {
1152 if (buf < end)
1153 *buf = separator;
1154 ++buf;
1155 }
1156 }
1157
1158 return buf;
1159 }
1160
1161 static noinline_for_stack
1162 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1163 struct printf_spec spec, const char *fmt)
1164 {
1165 const int CHUNKSZ = 32;
1166 int nr_bits = max_t(int, spec.field_width, 0);
1167 int i, chunksz;
1168 bool first = true;
1169
1170 if (check_pointer(&buf, end, bitmap, spec))
1171 return buf;
1172
1173 /* reused to print numbers */
1174 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1175
1176 chunksz = nr_bits & (CHUNKSZ - 1);
1177 if (chunksz == 0)
1178 chunksz = CHUNKSZ;
1179
1180 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1181 for (; i >= 0; i -= CHUNKSZ) {
1182 u32 chunkmask, val;
1183 int word, bit;
1184
1185 chunkmask = ((1ULL << chunksz) - 1);
1186 word = i / BITS_PER_LONG;
1187 bit = i % BITS_PER_LONG;
1188 val = (bitmap[word] >> bit) & chunkmask;
1189
1190 if (!first) {
1191 if (buf < end)
1192 *buf = ',';
1193 buf++;
1194 }
1195 first = false;
1196
1197 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1198 buf = number(buf, end, val, spec);
1199
1200 chunksz = CHUNKSZ;
1201 }
1202 return buf;
1203 }
1204
1205 static noinline_for_stack
1206 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1207 struct printf_spec spec, const char *fmt)
1208 {
1209 int nr_bits = max_t(int, spec.field_width, 0);
1210 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1211 int cur, rbot, rtop;
1212 bool first = true;
1213
1214 if (check_pointer(&buf, end, bitmap, spec))
1215 return buf;
1216
1217 rbot = cur = find_first_bit(bitmap, nr_bits);
1218 while (cur < nr_bits) {
1219 rtop = cur;
1220 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1221 if (cur < nr_bits && cur <= rtop + 1)
1222 continue;
1223
1224 if (!first) {
1225 if (buf < end)
1226 *buf = ',';
1227 buf++;
1228 }
1229 first = false;
1230
1231 buf = number(buf, end, rbot, default_dec_spec);
1232 if (rbot < rtop) {
1233 if (buf < end)
1234 *buf = '-';
1235 buf++;
1236
1237 buf = number(buf, end, rtop, default_dec_spec);
1238 }
1239
1240 rbot = cur;
1241 }
1242 return buf;
1243 }
1244
1245 static noinline_for_stack
1246 char *mac_address_string(char *buf, char *end, u8 *addr,
1247 struct printf_spec spec, const char *fmt)
1248 {
1249 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1250 char *p = mac_addr;
1251 int i;
1252 char separator;
1253 bool reversed = false;
1254
1255 if (check_pointer(&buf, end, addr, spec))
1256 return buf;
1257
1258 switch (fmt[1]) {
1259 case 'F':
1260 separator = '-';
1261 break;
1262
1263 case 'R':
1264 reversed = true;
1265 /* fall through */
1266
1267 default:
1268 separator = ':';
1269 break;
1270 }
1271
1272 for (i = 0; i < 6; i++) {
1273 if (reversed)
1274 p = hex_byte_pack(p, addr[5 - i]);
1275 else
1276 p = hex_byte_pack(p, addr[i]);
1277
1278 if (fmt[0] == 'M' && i != 5)
1279 *p++ = separator;
1280 }
1281 *p = '\0';
1282
1283 return string_nocheck(buf, end, mac_addr, spec);
1284 }
1285
1286 static noinline_for_stack
1287 char *ip4_string(char *p, const u8 *addr, const char *fmt)
1288 {
1289 int i;
1290 bool leading_zeros = (fmt[0] == 'i');
1291 int index;
1292 int step;
1293
1294 switch (fmt[2]) {
1295 case 'h':
1296 #ifdef __BIG_ENDIAN
1297 index = 0;
1298 step = 1;
1299 #else
1300 index = 3;
1301 step = -1;
1302 #endif
1303 break;
1304 case 'l':
1305 index = 3;
1306 step = -1;
1307 break;
1308 case 'n':
1309 case 'b':
1310 default:
1311 index = 0;
1312 step = 1;
1313 break;
1314 }
1315 for (i = 0; i < 4; i++) {
1316 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1317 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1318 if (leading_zeros) {
1319 if (digits < 3)
1320 *p++ = '0';
1321 if (digits < 2)
1322 *p++ = '0';
1323 }
1324 /* reverse the digits in the quad */
1325 while (digits--)
1326 *p++ = temp[digits];
1327 if (i < 3)
1328 *p++ = '.';
1329 index += step;
1330 }
1331 *p = '\0';
1332
1333 return p;
1334 }
1335
1336 static noinline_for_stack
1337 char *ip6_compressed_string(char *p, const char *addr)
1338 {
1339 int i, j, range;
1340 unsigned char zerolength[8];
1341 int longest = 1;
1342 int colonpos = -1;
1343 u16 word;
1344 u8 hi, lo;
1345 bool needcolon = false;
1346 bool useIPv4;
1347 struct in6_addr in6;
1348
1349 memcpy(&in6, addr, sizeof(struct in6_addr));
1350
1351 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1352
1353 memset(zerolength, 0, sizeof(zerolength));
1354
1355 if (useIPv4)
1356 range = 6;
1357 else
1358 range = 8;
1359
1360 /* find position of longest 0 run */
1361 for (i = 0; i < range; i++) {
1362 for (j = i; j < range; j++) {
1363 if (in6.s6_addr16[j] != 0)
1364 break;
1365 zerolength[i]++;
1366 }
1367 }
1368 for (i = 0; i < range; i++) {
1369 if (zerolength[i] > longest) {
1370 longest = zerolength[i];
1371 colonpos = i;
1372 }
1373 }
1374 if (longest == 1) /* don't compress a single 0 */
1375 colonpos = -1;
1376
1377 /* emit address */
1378 for (i = 0; i < range; i++) {
1379 if (i == colonpos) {
1380 if (needcolon || i == 0)
1381 *p++ = ':';
1382 *p++ = ':';
1383 needcolon = false;
1384 i += longest - 1;
1385 continue;
1386 }
1387 if (needcolon) {
1388 *p++ = ':';
1389 needcolon = false;
1390 }
1391 /* hex u16 without leading 0s */
1392 word = ntohs(in6.s6_addr16[i]);
1393 hi = word >> 8;
1394 lo = word & 0xff;
1395 if (hi) {
1396 if (hi > 0x0f)
1397 p = hex_byte_pack(p, hi);
1398 else
1399 *p++ = hex_asc_lo(hi);
1400 p = hex_byte_pack(p, lo);
1401 }
1402 else if (lo > 0x0f)
1403 p = hex_byte_pack(p, lo);
1404 else
1405 *p++ = hex_asc_lo(lo);
1406 needcolon = true;
1407 }
1408
1409 if (useIPv4) {
1410 if (needcolon)
1411 *p++ = ':';
1412 p = ip4_string(p, &in6.s6_addr[12], "I4");
1413 }
1414 *p = '\0';
1415
1416 return p;
1417 }
1418
1419 static noinline_for_stack
1420 char *ip6_string(char *p, const char *addr, const char *fmt)
1421 {
1422 int i;
1423
1424 for (i = 0; i < 8; i++) {
1425 p = hex_byte_pack(p, *addr++);
1426 p = hex_byte_pack(p, *addr++);
1427 if (fmt[0] == 'I' && i != 7)
1428 *p++ = ':';
1429 }
1430 *p = '\0';
1431
1432 return p;
1433 }
1434
1435 static noinline_for_stack
1436 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1437 struct printf_spec spec, const char *fmt)
1438 {
1439 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1440
1441 if (fmt[0] == 'I' && fmt[2] == 'c')
1442 ip6_compressed_string(ip6_addr, addr);
1443 else
1444 ip6_string(ip6_addr, addr, fmt);
1445
1446 return string_nocheck(buf, end, ip6_addr, spec);
1447 }
1448
1449 static noinline_for_stack
1450 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1451 struct printf_spec spec, const char *fmt)
1452 {
1453 char ip4_addr[sizeof("255.255.255.255")];
1454
1455 ip4_string(ip4_addr, addr, fmt);
1456
1457 return string_nocheck(buf, end, ip4_addr, spec);
1458 }
1459
1460 static noinline_for_stack
1461 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1462 struct printf_spec spec, const char *fmt)
1463 {
1464 bool have_p = false, have_s = false, have_f = false, have_c = false;
1465 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1466 sizeof(":12345") + sizeof("/123456789") +
1467 sizeof("%1234567890")];
1468 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1469 const u8 *addr = (const u8 *) &sa->sin6_addr;
1470 char fmt6[2] = { fmt[0], '6' };
1471 u8 off = 0;
1472
1473 fmt++;
1474 while (isalpha(*++fmt)) {
1475 switch (*fmt) {
1476 case 'p':
1477 have_p = true;
1478 break;
1479 case 'f':
1480 have_f = true;
1481 break;
1482 case 's':
1483 have_s = true;
1484 break;
1485 case 'c':
1486 have_c = true;
1487 break;
1488 }
1489 }
1490
1491 if (have_p || have_s || have_f) {
1492 *p = '[';
1493 off = 1;
1494 }
1495
1496 if (fmt6[0] == 'I' && have_c)
1497 p = ip6_compressed_string(ip6_addr + off, addr);
1498 else
1499 p = ip6_string(ip6_addr + off, addr, fmt6);
1500
1501 if (have_p || have_s || have_f)
1502 *p++ = ']';
1503
1504 if (have_p) {
1505 *p++ = ':';
1506 p = number(p, pend, ntohs(sa->sin6_port), spec);
1507 }
1508 if (have_f) {
1509 *p++ = '/';
1510 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1511 IPV6_FLOWINFO_MASK), spec);
1512 }
1513 if (have_s) {
1514 *p++ = '%';
1515 p = number(p, pend, sa->sin6_scope_id, spec);
1516 }
1517 *p = '\0';
1518
1519 return string_nocheck(buf, end, ip6_addr, spec);
1520 }
1521
1522 static noinline_for_stack
1523 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1524 struct printf_spec spec, const char *fmt)
1525 {
1526 bool have_p = false;
1527 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1528 char *pend = ip4_addr + sizeof(ip4_addr);
1529 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1530 char fmt4[3] = { fmt[0], '4', 0 };
1531
1532 fmt++;
1533 while (isalpha(*++fmt)) {
1534 switch (*fmt) {
1535 case 'p':
1536 have_p = true;
1537 break;
1538 case 'h':
1539 case 'l':
1540 case 'n':
1541 case 'b':
1542 fmt4[2] = *fmt;
1543 break;
1544 }
1545 }
1546
1547 p = ip4_string(ip4_addr, addr, fmt4);
1548 if (have_p) {
1549 *p++ = ':';
1550 p = number(p, pend, ntohs(sa->sin_port), spec);
1551 }
1552 *p = '\0';
1553
1554 return string_nocheck(buf, end, ip4_addr, spec);
1555 }
1556
1557 static noinline_for_stack
1558 char *ip_addr_string(char *buf, char *end, const void *ptr,
1559 struct printf_spec spec, const char *fmt)
1560 {
1561 char *err_fmt_msg;
1562
1563 if (check_pointer(&buf, end, ptr, spec))
1564 return buf;
1565
1566 switch (fmt[1]) {
1567 case '6':
1568 return ip6_addr_string(buf, end, ptr, spec, fmt);
1569 case '4':
1570 return ip4_addr_string(buf, end, ptr, spec, fmt);
1571 case 'S': {
1572 const union {
1573 struct sockaddr raw;
1574 struct sockaddr_in v4;
1575 struct sockaddr_in6 v6;
1576 } *sa = ptr;
1577
1578 switch (sa->raw.sa_family) {
1579 case AF_INET:
1580 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1581 case AF_INET6:
1582 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1583 default:
1584 return error_string(buf, end, "(einval)", spec);
1585 }}
1586 }
1587
1588 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1589 return error_string(buf, end, err_fmt_msg, spec);
1590 }
1591
1592 static noinline_for_stack
1593 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1594 const char *fmt)
1595 {
1596 bool found = true;
1597 int count = 1;
1598 unsigned int flags = 0;
1599 int len;
1600
1601 if (spec.field_width == 0)
1602 return buf; /* nothing to print */
1603
1604 if (check_pointer(&buf, end, addr, spec))
1605 return buf;
1606
1607 do {
1608 switch (fmt[count++]) {
1609 case 'a':
1610 flags |= ESCAPE_ANY;
1611 break;
1612 case 'c':
1613 flags |= ESCAPE_SPECIAL;
1614 break;
1615 case 'h':
1616 flags |= ESCAPE_HEX;
1617 break;
1618 case 'n':
1619 flags |= ESCAPE_NULL;
1620 break;
1621 case 'o':
1622 flags |= ESCAPE_OCTAL;
1623 break;
1624 case 'p':
1625 flags |= ESCAPE_NP;
1626 break;
1627 case 's':
1628 flags |= ESCAPE_SPACE;
1629 break;
1630 default:
1631 found = false;
1632 break;
1633 }
1634 } while (found);
1635
1636 if (!flags)
1637 flags = ESCAPE_ANY_NP;
1638
1639 len = spec.field_width < 0 ? 1 : spec.field_width;
1640
1641 /*
1642 * string_escape_mem() writes as many characters as it can to
1643 * the given buffer, and returns the total size of the output
1644 * had the buffer been big enough.
1645 */
1646 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1647
1648 return buf;
1649 }
1650
1651 static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1652 struct printf_spec spec, const char *fmt)
1653 {
1654 va_list va;
1655
1656 if (check_pointer(&buf, end, va_fmt, spec))
1657 return buf;
1658
1659 va_copy(va, *va_fmt->va);
1660 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1661 va_end(va);
1662
1663 return buf;
1664 }
1665
1666 static noinline_for_stack
1667 char *uuid_string(char *buf, char *end, const u8 *addr,
1668 struct printf_spec spec, const char *fmt)
1669 {
1670 char uuid[UUID_STRING_LEN + 1];
1671 char *p = uuid;
1672 int i;
1673 const u8 *index = uuid_index;
1674 bool uc = false;
1675
1676 if (check_pointer(&buf, end, addr, spec))
1677 return buf;
1678
1679 switch (*(++fmt)) {
1680 case 'L':
1681 uc = true; /* fall-through */
1682 case 'l':
1683 index = guid_index;
1684 break;
1685 case 'B':
1686 uc = true;
1687 break;
1688 }
1689
1690 for (i = 0; i < 16; i++) {
1691 if (uc)
1692 p = hex_byte_pack_upper(p, addr[index[i]]);
1693 else
1694 p = hex_byte_pack(p, addr[index[i]]);
1695 switch (i) {
1696 case 3:
1697 case 5:
1698 case 7:
1699 case 9:
1700 *p++ = '-';
1701 break;
1702 }
1703 }
1704
1705 *p = 0;
1706
1707 return string_nocheck(buf, end, uuid, spec);
1708 }
1709
1710 static noinline_for_stack
1711 char *netdev_bits(char *buf, char *end, const void *addr,
1712 struct printf_spec spec, const char *fmt)
1713 {
1714 unsigned long long num;
1715 int size;
1716
1717 if (check_pointer(&buf, end, addr, spec))
1718 return buf;
1719
1720 switch (fmt[1]) {
1721 case 'F':
1722 num = *(const netdev_features_t *)addr;
1723 size = sizeof(netdev_features_t);
1724 break;
1725 default:
1726 return error_string(buf, end, "(%pN?)", spec);
1727 }
1728
1729 return special_hex_number(buf, end, num, size);
1730 }
1731
1732 static noinline_for_stack
1733 char *address_val(char *buf, char *end, const void *addr,
1734 struct printf_spec spec, const char *fmt)
1735 {
1736 unsigned long long num;
1737 int size;
1738
1739 if (check_pointer(&buf, end, addr, spec))
1740 return buf;
1741
1742 switch (fmt[1]) {
1743 case 'd':
1744 num = *(const dma_addr_t *)addr;
1745 size = sizeof(dma_addr_t);
1746 break;
1747 case 'p':
1748 default:
1749 num = *(const phys_addr_t *)addr;
1750 size = sizeof(phys_addr_t);
1751 break;
1752 }
1753
1754 return special_hex_number(buf, end, num, size);
1755 }
1756
1757 static noinline_for_stack
1758 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1759 {
1760 int year = tm->tm_year + (r ? 0 : 1900);
1761 int mon = tm->tm_mon + (r ? 0 : 1);
1762
1763 buf = number(buf, end, year, default_dec04_spec);
1764 if (buf < end)
1765 *buf = '-';
1766 buf++;
1767
1768 buf = number(buf, end, mon, default_dec02_spec);
1769 if (buf < end)
1770 *buf = '-';
1771 buf++;
1772
1773 return number(buf, end, tm->tm_mday, default_dec02_spec);
1774 }
1775
1776 static noinline_for_stack
1777 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1778 {
1779 buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1780 if (buf < end)
1781 *buf = ':';
1782 buf++;
1783
1784 buf = number(buf, end, tm->tm_min, default_dec02_spec);
1785 if (buf < end)
1786 *buf = ':';
1787 buf++;
1788
1789 return number(buf, end, tm->tm_sec, default_dec02_spec);
1790 }
1791
1792 static noinline_for_stack
1793 char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1794 struct printf_spec spec, const char *fmt)
1795 {
1796 bool have_t = true, have_d = true;
1797 bool raw = false;
1798 int count = 2;
1799
1800 if (check_pointer(&buf, end, tm, spec))
1801 return buf;
1802
1803 switch (fmt[count]) {
1804 case 'd':
1805 have_t = false;
1806 count++;
1807 break;
1808 case 't':
1809 have_d = false;
1810 count++;
1811 break;
1812 }
1813
1814 raw = fmt[count] == 'r';
1815
1816 if (have_d)
1817 buf = date_str(buf, end, tm, raw);
1818 if (have_d && have_t) {
1819 /* Respect ISO 8601 */
1820 if (buf < end)
1821 *buf = 'T';
1822 buf++;
1823 }
1824 if (have_t)
1825 buf = time_str(buf, end, tm, raw);
1826
1827 return buf;
1828 }
1829
1830 static noinline_for_stack
1831 char *time64_str(char *buf, char *end, const time64_t time,
1832 struct printf_spec spec, const char *fmt)
1833 {
1834 struct rtc_time rtc_time;
1835 struct tm tm;
1836
1837 time64_to_tm(time, 0, &tm);
1838
1839 rtc_time.tm_sec = tm.tm_sec;
1840 rtc_time.tm_min = tm.tm_min;
1841 rtc_time.tm_hour = tm.tm_hour;
1842 rtc_time.tm_mday = tm.tm_mday;
1843 rtc_time.tm_mon = tm.tm_mon;
1844 rtc_time.tm_year = tm.tm_year;
1845 rtc_time.tm_wday = tm.tm_wday;
1846 rtc_time.tm_yday = tm.tm_yday;
1847
1848 rtc_time.tm_isdst = 0;
1849
1850 return rtc_str(buf, end, &rtc_time, spec, fmt);
1851 }
1852
1853 static noinline_for_stack
1854 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1855 const char *fmt)
1856 {
1857 switch (fmt[1]) {
1858 case 'R':
1859 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1860 case 'T':
1861 return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt);
1862 default:
1863 return error_string(buf, end, "(%pt?)", spec);
1864 }
1865 }
1866
1867 static noinline_for_stack
1868 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1869 const char *fmt)
1870 {
1871 if (!IS_ENABLED(CONFIG_HAVE_CLK))
1872 return error_string(buf, end, "(%pC?)", spec);
1873
1874 if (check_pointer(&buf, end, clk, spec))
1875 return buf;
1876
1877 switch (fmt[1]) {
1878 case 'n':
1879 default:
1880 #ifdef CONFIG_COMMON_CLK
1881 return string(buf, end, __clk_get_name(clk), spec);
1882 #else
1883 return ptr_to_id(buf, end, clk, spec);
1884 #endif
1885 }
1886 }
1887
1888 static
1889 char *format_flags(char *buf, char *end, unsigned long flags,
1890 const struct trace_print_flags *names)
1891 {
1892 unsigned long mask;
1893
1894 for ( ; flags && names->name; names++) {
1895 mask = names->mask;
1896 if ((flags & mask) != mask)
1897 continue;
1898
1899 buf = string(buf, end, names->name, default_str_spec);
1900
1901 flags &= ~mask;
1902 if (flags) {
1903 if (buf < end)
1904 *buf = '|';
1905 buf++;
1906 }
1907 }
1908
1909 if (flags)
1910 buf = number(buf, end, flags, default_flag_spec);
1911
1912 return buf;
1913 }
1914
1915 static noinline_for_stack
1916 char *flags_string(char *buf, char *end, void *flags_ptr,
1917 struct printf_spec spec, const char *fmt)
1918 {
1919 unsigned long flags;
1920 const struct trace_print_flags *names;
1921
1922 if (check_pointer(&buf, end, flags_ptr, spec))
1923 return buf;
1924
1925 switch (fmt[1]) {
1926 case 'p':
1927 flags = *(unsigned long *)flags_ptr;
1928 /* Remove zone id */
1929 flags &= (1UL << NR_PAGEFLAGS) - 1;
1930 names = pageflag_names;
1931 break;
1932 case 'v':
1933 flags = *(unsigned long *)flags_ptr;
1934 names = vmaflag_names;
1935 break;
1936 case 'g':
1937 flags = *(gfp_t *)flags_ptr;
1938 names = gfpflag_names;
1939 break;
1940 default:
1941 return error_string(buf, end, "(%pG?)", spec);
1942 }
1943
1944 return format_flags(buf, end, flags, names);
1945 }
1946
1947 static noinline_for_stack
1948 char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf,
1949 char *end)
1950 {
1951 int depth;
1952
1953 /* Loop starting from the root node to the current node. */
1954 for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) {
1955 struct fwnode_handle *__fwnode =
1956 fwnode_get_nth_parent(fwnode, depth);
1957
1958 buf = string(buf, end, fwnode_get_name_prefix(__fwnode),
1959 default_str_spec);
1960 buf = string(buf, end, fwnode_get_name(__fwnode),
1961 default_str_spec);
1962
1963 fwnode_handle_put(__fwnode);
1964 }
1965
1966 return buf;
1967 }
1968
1969 static noinline_for_stack
1970 char *device_node_string(char *buf, char *end, struct device_node *dn,
1971 struct printf_spec spec, const char *fmt)
1972 {
1973 char tbuf[sizeof("xxxx") + 1];
1974 const char *p;
1975 int ret;
1976 char *buf_start = buf;
1977 struct property *prop;
1978 bool has_mult, pass;
1979 static const struct printf_spec num_spec = {
1980 .flags = SMALL,
1981 .field_width = -1,
1982 .precision = -1,
1983 .base = 10,
1984 };
1985
1986 struct printf_spec str_spec = spec;
1987 str_spec.field_width = -1;
1988
1989 if (fmt[0] != 'F')
1990 return error_string(buf, end, "(%pO?)", spec);
1991
1992 if (!IS_ENABLED(CONFIG_OF))
1993 return error_string(buf, end, "(%pOF?)", spec);
1994
1995 if (check_pointer(&buf, end, dn, spec))
1996 return buf;
1997
1998 /* simple case without anything any more format specifiers */
1999 fmt++;
2000 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
2001 fmt = "f";
2002
2003 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
2004 int precision;
2005 if (pass) {
2006 if (buf < end)
2007 *buf = ':';
2008 buf++;
2009 }
2010
2011 switch (*fmt) {
2012 case 'f': /* full_name */
2013 buf = fwnode_full_name_string(of_fwnode_handle(dn), buf,
2014 end);
2015 break;
2016 case 'n': /* name */
2017 p = fwnode_get_name(of_fwnode_handle(dn));
2018 precision = str_spec.precision;
2019 str_spec.precision = strchrnul(p, '@') - p;
2020 buf = string(buf, end, p, str_spec);
2021 str_spec.precision = precision;
2022 break;
2023 case 'p': /* phandle */
2024 buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
2025 break;
2026 case 'P': /* path-spec */
2027 p = fwnode_get_name(of_fwnode_handle(dn));
2028 if (!p[1])
2029 p = "/";
2030 buf = string(buf, end, p, str_spec);
2031 break;
2032 case 'F': /* flags */
2033 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
2034 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
2035 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
2036 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
2037 tbuf[4] = 0;
2038 buf = string_nocheck(buf, end, tbuf, str_spec);
2039 break;
2040 case 'c': /* major compatible string */
2041 ret = of_property_read_string(dn, "compatible", &p);
2042 if (!ret)
2043 buf = string(buf, end, p, str_spec);
2044 break;
2045 case 'C': /* full compatible string */
2046 has_mult = false;
2047 of_property_for_each_string(dn, "compatible", prop, p) {
2048 if (has_mult)
2049 buf = string_nocheck(buf, end, ",", str_spec);
2050 buf = string_nocheck(buf, end, "\"", str_spec);
2051 buf = string(buf, end, p, str_spec);
2052 buf = string_nocheck(buf, end, "\"", str_spec);
2053
2054 has_mult = true;
2055 }
2056 break;
2057 default:
2058 break;
2059 }
2060 }
2061
2062 return widen_string(buf, buf - buf_start, end, spec);
2063 }
2064
2065 static noinline_for_stack
2066 char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode,
2067 struct printf_spec spec, const char *fmt)
2068 {
2069 struct printf_spec str_spec = spec;
2070 char *buf_start = buf;
2071
2072 str_spec.field_width = -1;
2073
2074 if (*fmt != 'w')
2075 return error_string(buf, end, "(%pf?)", spec);
2076
2077 if (check_pointer(&buf, end, fwnode, spec))
2078 return buf;
2079
2080 fmt++;
2081
2082 switch (*fmt) {
2083 case 'P': /* name */
2084 buf = string(buf, end, fwnode_get_name(fwnode), str_spec);
2085 break;
2086 case 'f': /* full_name */
2087 default:
2088 buf = fwnode_full_name_string(fwnode, buf, end);
2089 break;
2090 }
2091
2092 return widen_string(buf, buf - buf_start, end, spec);
2093 }
2094
2095 /*
2096 * Show a '%p' thing. A kernel extension is that the '%p' is followed
2097 * by an extra set of alphanumeric characters that are extended format
2098 * specifiers.
2099 *
2100 * Please update scripts/checkpatch.pl when adding/removing conversion
2101 * characters. (Search for "check for vsprintf extension").
2102 *
2103 * Right now we handle:
2104 *
2105 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2106 * - 's' For symbolic direct pointers (or function descriptors) without offset
2107 * - '[Ss]R' as above with __builtin_extract_return_addr() translation
2108 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of
2109 * %ps and %pS. Be careful when re-using these specifiers.
2110 * - 'B' For backtraced symbolic direct pointers with offset
2111 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2112 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2113 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2114 * width which must be explicitly specified either as part of the
2115 * format string '%32b[l]' or through '%*b[l]', [l] selects
2116 * range-list format instead of hex format
2117 * - 'M' For a 6-byte MAC address, it prints the address in the
2118 * usual colon-separated hex notation
2119 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2120 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2121 * with a dash-separated hex notation
2122 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2123 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2124 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2125 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
2126 * [S][pfs]
2127 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2128 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2129 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2130 * IPv6 omits the colons (01020304...0f)
2131 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2132 * [S][pfs]
2133 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2134 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2135 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2136 * - 'I[6S]c' for IPv6 addresses printed as specified by
2137 * http://tools.ietf.org/html/rfc5952
2138 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2139 * of the following flags (see string_escape_mem() for the
2140 * details):
2141 * a - ESCAPE_ANY
2142 * c - ESCAPE_SPECIAL
2143 * h - ESCAPE_HEX
2144 * n - ESCAPE_NULL
2145 * o - ESCAPE_OCTAL
2146 * p - ESCAPE_NP
2147 * s - ESCAPE_SPACE
2148 * By default ESCAPE_ANY_NP is used.
2149 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2150 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2151 * Options for %pU are:
2152 * b big endian lower case hex (default)
2153 * B big endian UPPER case hex
2154 * l little endian lower case hex
2155 * L little endian UPPER case hex
2156 * big endian output byte order is:
2157 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2158 * little endian output byte order is:
2159 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2160 * - 'V' For a struct va_format which contains a format string * and va_list *,
2161 * call vsnprintf(->format, *->va_list).
2162 * Implements a "recursive vsnprintf".
2163 * Do not use this feature without some mechanism to verify the
2164 * correctness of the format string and va_list arguments.
2165 * - 'K' For a kernel pointer that should be hidden from unprivileged users
2166 * - 'NF' For a netdev_features_t
2167 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2168 * a certain separator (' ' by default):
2169 * C colon
2170 * D dash
2171 * N no separator
2172 * The maximum supported length is 64 bytes of the input. Consider
2173 * to use print_hex_dump() for the larger input.
2174 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2175 * (default assumed to be phys_addr_t, passed by reference)
2176 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2177 * - 'D[234]' Same as 'd' but for a struct file
2178 * - 'g' For block_device name (gendisk + partition number)
2179 * - 't[RT][dt][r]' For time and date as represented by:
2180 * R struct rtc_time
2181 * T time64_t
2182 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2183 * (legacy clock framework) of the clock
2184 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2185 * (legacy clock framework) of the clock
2186 * - 'G' For flags to be printed as a collection of symbolic strings that would
2187 * construct the specific value. Supported flags given by option:
2188 * p page flags (see struct page) given as pointer to unsigned long
2189 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2190 * v vma flags (VM_*) given as pointer to unsigned long
2191 * - 'OF[fnpPcCF]' For a device tree object
2192 * Without any optional arguments prints the full_name
2193 * f device node full_name
2194 * n device node name
2195 * p device node phandle
2196 * P device node path spec (name + @unit)
2197 * F device node flags
2198 * c major compatible string
2199 * C full compatible string
2200 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer
2201 * Without an option prints the full name of the node
2202 * f full name
2203 * P node name, including a possible unit address
2204 * - 'x' For printing the address. Equivalent to "%lx".
2205 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of
2206 * bpf_trace_printk() where [ku] prefix specifies either kernel (k)
2207 * or user (u) memory to probe, and:
2208 * s a string, equivalent to "%s" on direct vsnprintf() use
2209 *
2210 * ** When making changes please also update:
2211 * Documentation/core-api/printk-formats.rst
2212 *
2213 * Note: The default behaviour (unadorned %p) is to hash the address,
2214 * rendering it useful as a unique identifier.
2215 */
2216 static noinline_for_stack
2217 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2218 struct printf_spec spec)
2219 {
2220 switch (*fmt) {
2221 case 'S':
2222 case 's':
2223 ptr = dereference_symbol_descriptor(ptr);
2224 /* Fallthrough */
2225 case 'B':
2226 return symbol_string(buf, end, ptr, spec, fmt);
2227 case 'R':
2228 case 'r':
2229 return resource_string(buf, end, ptr, spec, fmt);
2230 case 'h':
2231 return hex_string(buf, end, ptr, spec, fmt);
2232 case 'b':
2233 switch (fmt[1]) {
2234 case 'l':
2235 return bitmap_list_string(buf, end, ptr, spec, fmt);
2236 default:
2237 return bitmap_string(buf, end, ptr, spec, fmt);
2238 }
2239 case 'M': /* Colon separated: 00:01:02:03:04:05 */
2240 case 'm': /* Contiguous: 000102030405 */
2241 /* [mM]F (FDDI) */
2242 /* [mM]R (Reverse order; Bluetooth) */
2243 return mac_address_string(buf, end, ptr, spec, fmt);
2244 case 'I': /* Formatted IP supported
2245 * 4: 1.2.3.4
2246 * 6: 0001:0203:...:0708
2247 * 6c: 1::708 or 1::1.2.3.4
2248 */
2249 case 'i': /* Contiguous:
2250 * 4: 001.002.003.004
2251 * 6: 000102...0f
2252 */
2253 return ip_addr_string(buf, end, ptr, spec, fmt);
2254 case 'E':
2255 return escaped_string(buf, end, ptr, spec, fmt);
2256 case 'U':
2257 return uuid_string(buf, end, ptr, spec, fmt);
2258 case 'V':
2259 return va_format(buf, end, ptr, spec, fmt);
2260 case 'K':
2261 return restricted_pointer(buf, end, ptr, spec);
2262 case 'N':
2263 return netdev_bits(buf, end, ptr, spec, fmt);
2264 case 'a':
2265 return address_val(buf, end, ptr, spec, fmt);
2266 case 'd':
2267 return dentry_name(buf, end, ptr, spec, fmt);
2268 case 't':
2269 return time_and_date(buf, end, ptr, spec, fmt);
2270 case 'C':
2271 return clock(buf, end, ptr, spec, fmt);
2272 case 'D':
2273 return file_dentry_name(buf, end, ptr, spec, fmt);
2274 #ifdef CONFIG_BLOCK
2275 case 'g':
2276 return bdev_name(buf, end, ptr, spec, fmt);
2277 #endif
2278
2279 case 'G':
2280 return flags_string(buf, end, ptr, spec, fmt);
2281 case 'O':
2282 return device_node_string(buf, end, ptr, spec, fmt + 1);
2283 case 'f':
2284 return fwnode_string(buf, end, ptr, spec, fmt + 1);
2285 case 'x':
2286 return pointer_string(buf, end, ptr, spec);
2287 case 'e':
2288 /* %pe with a non-ERR_PTR gets treated as plain %p */
2289 if (!IS_ERR(ptr))
2290 break;
2291 return err_ptr(buf, end, ptr, spec);
2292 case 'u':
2293 case 'k':
2294 switch (fmt[1]) {
2295 case 's':
2296 return string(buf, end, ptr, spec);
2297 default:
2298 return error_string(buf, end, "(einval)", spec);
2299 }
2300 }
2301
2302 /* default is to _not_ leak addresses, hash before printing */
2303 return ptr_to_id(buf, end, ptr, spec);
2304 }
2305
2306 /*
2307 * Helper function to decode printf style format.
2308 * Each call decode a token from the format and return the
2309 * number of characters read (or likely the delta where it wants
2310 * to go on the next call).
2311 * The decoded token is returned through the parameters
2312 *
2313 * 'h', 'l', or 'L' for integer fields
2314 * 'z' support added 23/7/1999 S.H.
2315 * 'z' changed to 'Z' --davidm 1/25/99
2316 * 'Z' changed to 'z' --adobriyan 2017-01-25
2317 * 't' added for ptrdiff_t
2318 *
2319 * @fmt: the format string
2320 * @type of the token returned
2321 * @flags: various flags such as +, -, # tokens..
2322 * @field_width: overwritten width
2323 * @base: base of the number (octal, hex, ...)
2324 * @precision: precision of a number
2325 * @qualifier: qualifier of a number (long, size_t, ...)
2326 */
2327 static noinline_for_stack
2328 int format_decode(const char *fmt, struct printf_spec *spec)
2329 {
2330 const char *start = fmt;
2331 char qualifier;
2332
2333 /* we finished early by reading the field width */
2334 if (spec->type == FORMAT_TYPE_WIDTH) {
2335 if (spec->field_width < 0) {
2336 spec->field_width = -spec->field_width;
2337 spec->flags |= LEFT;
2338 }
2339 spec->type = FORMAT_TYPE_NONE;
2340 goto precision;
2341 }
2342
2343 /* we finished early by reading the precision */
2344 if (spec->type == FORMAT_TYPE_PRECISION) {
2345 if (spec->precision < 0)
2346 spec->precision = 0;
2347
2348 spec->type = FORMAT_TYPE_NONE;
2349 goto qualifier;
2350 }
2351
2352 /* By default */
2353 spec->type = FORMAT_TYPE_NONE;
2354
2355 for (; *fmt ; ++fmt) {
2356 if (*fmt == '%')
2357 break;
2358 }
2359
2360 /* Return the current non-format string */
2361 if (fmt != start || !*fmt)
2362 return fmt - start;
2363
2364 /* Process flags */
2365 spec->flags = 0;
2366
2367 while (1) { /* this also skips first '%' */
2368 bool found = true;
2369
2370 ++fmt;
2371
2372 switch (*fmt) {
2373 case '-': spec->flags |= LEFT; break;
2374 case '+': spec->flags |= PLUS; break;
2375 case ' ': spec->flags |= SPACE; break;
2376 case '#': spec->flags |= SPECIAL; break;
2377 case '0': spec->flags |= ZEROPAD; break;
2378 default: found = false;
2379 }
2380
2381 if (!found)
2382 break;
2383 }
2384
2385 /* get field width */
2386 spec->field_width = -1;
2387
2388 if (isdigit(*fmt))
2389 spec->field_width = skip_atoi(&fmt);
2390 else if (*fmt == '*') {
2391 /* it's the next argument */
2392 spec->type = FORMAT_TYPE_WIDTH;
2393 return ++fmt - start;
2394 }
2395
2396 precision:
2397 /* get the precision */
2398 spec->precision = -1;
2399 if (*fmt == '.') {
2400 ++fmt;
2401 if (isdigit(*fmt)) {
2402 spec->precision = skip_atoi(&fmt);
2403 if (spec->precision < 0)
2404 spec->precision = 0;
2405 } else if (*fmt == '*') {
2406 /* it's the next argument */
2407 spec->type = FORMAT_TYPE_PRECISION;
2408 return ++fmt - start;
2409 }
2410 }
2411
2412 qualifier:
2413 /* get the conversion qualifier */
2414 qualifier = 0;
2415 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2416 *fmt == 'z' || *fmt == 't') {
2417 qualifier = *fmt++;
2418 if (unlikely(qualifier == *fmt)) {
2419 if (qualifier == 'l') {
2420 qualifier = 'L';
2421 ++fmt;
2422 } else if (qualifier == 'h') {
2423 qualifier = 'H';
2424 ++fmt;
2425 }
2426 }
2427 }
2428
2429 /* default base */
2430 spec->base = 10;
2431 switch (*fmt) {
2432 case 'c':
2433 spec->type = FORMAT_TYPE_CHAR;
2434 return ++fmt - start;
2435
2436 case 's':
2437 spec->type = FORMAT_TYPE_STR;
2438 return ++fmt - start;
2439
2440 case 'p':
2441 spec->type = FORMAT_TYPE_PTR;
2442 return ++fmt - start;
2443
2444 case '%':
2445 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2446 return ++fmt - start;
2447
2448 /* integer number formats - set up the flags and "break" */
2449 case 'o':
2450 spec->base = 8;
2451 break;
2452
2453 case 'x':
2454 spec->flags |= SMALL;
2455 /* fall through */
2456
2457 case 'X':
2458 spec->base = 16;
2459 break;
2460
2461 case 'd':
2462 case 'i':
2463 spec->flags |= SIGN;
2464 case 'u':
2465 break;
2466
2467 case 'n':
2468 /*
2469 * Since %n poses a greater security risk than
2470 * utility, treat it as any other invalid or
2471 * unsupported format specifier.
2472 */
2473 /* Fall-through */
2474
2475 default:
2476 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2477 spec->type = FORMAT_TYPE_INVALID;
2478 return fmt - start;
2479 }
2480
2481 if (qualifier == 'L')
2482 spec->type = FORMAT_TYPE_LONG_LONG;
2483 else if (qualifier == 'l') {
2484 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2485 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2486 } else if (qualifier == 'z') {
2487 spec->type = FORMAT_TYPE_SIZE_T;
2488 } else if (qualifier == 't') {
2489 spec->type = FORMAT_TYPE_PTRDIFF;
2490 } else if (qualifier == 'H') {
2491 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2492 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2493 } else if (qualifier == 'h') {
2494 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2495 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2496 } else {
2497 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2498 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2499 }
2500
2501 return ++fmt - start;
2502 }
2503
2504 static void
2505 set_field_width(struct printf_spec *spec, int width)
2506 {
2507 spec->field_width = width;
2508 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2509 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2510 }
2511 }
2512
2513 static void
2514 set_precision(struct printf_spec *spec, int prec)
2515 {
2516 spec->precision = prec;
2517 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2518 spec->precision = clamp(prec, 0, PRECISION_MAX);
2519 }
2520 }
2521
2522 /**
2523 * vsnprintf - Format a string and place it in a buffer
2524 * @buf: The buffer to place the result into
2525 * @size: The size of the buffer, including the trailing null space
2526 * @fmt: The format string to use
2527 * @args: Arguments for the format string
2528 *
2529 * This function generally follows C99 vsnprintf, but has some
2530 * extensions and a few limitations:
2531 *
2532 * - ``%n`` is unsupported
2533 * - ``%p*`` is handled by pointer()
2534 *
2535 * See pointer() or Documentation/core-api/printk-formats.rst for more
2536 * extensive description.
2537 *
2538 * **Please update the documentation in both places when making changes**
2539 *
2540 * The return value is the number of characters which would
2541 * be generated for the given input, excluding the trailing
2542 * '\0', as per ISO C99. If you want to have the exact
2543 * number of characters written into @buf as return value
2544 * (not including the trailing '\0'), use vscnprintf(). If the
2545 * return is greater than or equal to @size, the resulting
2546 * string is truncated.
2547 *
2548 * If you're not already dealing with a va_list consider using snprintf().
2549 */
2550 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2551 {
2552 unsigned long long num;
2553 char *str, *end;
2554 struct printf_spec spec = {0};
2555
2556 /* Reject out-of-range values early. Large positive sizes are
2557 used for unknown buffer sizes. */
2558 if (WARN_ON_ONCE(size > INT_MAX))
2559 return 0;
2560
2561 str = buf;
2562 end = buf + size;
2563
2564 /* Make sure end is always >= buf */
2565 if (end < buf) {
2566 end = ((void *)-1);
2567 size = end - buf;
2568 }
2569
2570 while (*fmt) {
2571 const char *old_fmt = fmt;
2572 int read = format_decode(fmt, &spec);
2573
2574 fmt += read;
2575
2576 switch (spec.type) {
2577 case FORMAT_TYPE_NONE: {
2578 int copy = read;
2579 if (str < end) {
2580 if (copy > end - str)
2581 copy = end - str;
2582 memcpy(str, old_fmt, copy);
2583 }
2584 str += read;
2585 break;
2586 }
2587
2588 case FORMAT_TYPE_WIDTH:
2589 set_field_width(&spec, va_arg(args, int));
2590 break;
2591
2592 case FORMAT_TYPE_PRECISION:
2593 set_precision(&spec, va_arg(args, int));
2594 break;
2595
2596 case FORMAT_TYPE_CHAR: {
2597 char c;
2598
2599 if (!(spec.flags & LEFT)) {
2600 while (--spec.field_width > 0) {
2601 if (str < end)
2602 *str = ' ';
2603 ++str;
2604
2605 }
2606 }
2607 c = (unsigned char) va_arg(args, int);
2608 if (str < end)
2609 *str = c;
2610 ++str;
2611 while (--spec.field_width > 0) {
2612 if (str < end)
2613 *str = ' ';
2614 ++str;
2615 }
2616 break;
2617 }
2618
2619 case FORMAT_TYPE_STR:
2620 str = string(str, end, va_arg(args, char *), spec);
2621 break;
2622
2623 case FORMAT_TYPE_PTR:
2624 str = pointer(fmt, str, end, va_arg(args, void *),
2625 spec);
2626 while (isalnum(*fmt))
2627 fmt++;
2628 break;
2629
2630 case FORMAT_TYPE_PERCENT_CHAR:
2631 if (str < end)
2632 *str = '%';
2633 ++str;
2634 break;
2635
2636 case FORMAT_TYPE_INVALID:
2637 /*
2638 * Presumably the arguments passed gcc's type
2639 * checking, but there is no safe or sane way
2640 * for us to continue parsing the format and
2641 * fetching from the va_list; the remaining
2642 * specifiers and arguments would be out of
2643 * sync.
2644 */
2645 goto out;
2646
2647 default:
2648 switch (spec.type) {
2649 case FORMAT_TYPE_LONG_LONG:
2650 num = va_arg(args, long long);
2651 break;
2652 case FORMAT_TYPE_ULONG:
2653 num = va_arg(args, unsigned long);
2654 break;
2655 case FORMAT_TYPE_LONG:
2656 num = va_arg(args, long);
2657 break;
2658 case FORMAT_TYPE_SIZE_T:
2659 if (spec.flags & SIGN)
2660 num = va_arg(args, ssize_t);
2661 else
2662 num = va_arg(args, size_t);
2663 break;
2664 case FORMAT_TYPE_PTRDIFF:
2665 num = va_arg(args, ptrdiff_t);
2666 break;
2667 case FORMAT_TYPE_UBYTE:
2668 num = (unsigned char) va_arg(args, int);
2669 break;
2670 case FORMAT_TYPE_BYTE:
2671 num = (signed char) va_arg(args, int);
2672 break;
2673 case FORMAT_TYPE_USHORT:
2674 num = (unsigned short) va_arg(args, int);
2675 break;
2676 case FORMAT_TYPE_SHORT:
2677 num = (short) va_arg(args, int);
2678 break;
2679 case FORMAT_TYPE_INT:
2680 num = (int) va_arg(args, int);
2681 break;
2682 default:
2683 num = va_arg(args, unsigned int);
2684 }
2685
2686 str = number(str, end, num, spec);
2687 }
2688 }
2689
2690 out:
2691 if (size > 0) {
2692 if (str < end)
2693 *str = '\0';
2694 else
2695 end[-1] = '\0';
2696 }
2697
2698 /* the trailing null byte doesn't count towards the total */
2699 return str-buf;
2700
2701 }
2702 EXPORT_SYMBOL(vsnprintf);
2703
2704 /**
2705 * vscnprintf - Format a string and place it in a buffer
2706 * @buf: The buffer to place the result into
2707 * @size: The size of the buffer, including the trailing null space
2708 * @fmt: The format string to use
2709 * @args: Arguments for the format string
2710 *
2711 * The return value is the number of characters which have been written into
2712 * the @buf not including the trailing '\0'. If @size is == 0 the function
2713 * returns 0.
2714 *
2715 * If you're not already dealing with a va_list consider using scnprintf().
2716 *
2717 * See the vsnprintf() documentation for format string extensions over C99.
2718 */
2719 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2720 {
2721 int i;
2722
2723 i = vsnprintf(buf, size, fmt, args);
2724
2725 if (likely(i < size))
2726 return i;
2727 if (size != 0)
2728 return size - 1;
2729 return 0;
2730 }
2731 EXPORT_SYMBOL(vscnprintf);
2732
2733 /**
2734 * snprintf - Format a string and place it in a buffer
2735 * @buf: The buffer to place the result into
2736 * @size: The size of the buffer, including the trailing null space
2737 * @fmt: The format string to use
2738 * @...: Arguments for the format string
2739 *
2740 * The return value is the number of characters which would be
2741 * generated for the given input, excluding the trailing null,
2742 * as per ISO C99. If the return is greater than or equal to
2743 * @size, the resulting string is truncated.
2744 *
2745 * See the vsnprintf() documentation for format string extensions over C99.
2746 */
2747 int snprintf(char *buf, size_t size, const char *fmt, ...)
2748 {
2749 va_list args;
2750 int i;
2751
2752 va_start(args, fmt);
2753 i = vsnprintf(buf, size, fmt, args);
2754 va_end(args);
2755
2756 return i;
2757 }
2758 EXPORT_SYMBOL(snprintf);
2759
2760 /**
2761 * scnprintf - Format a string and place it in a buffer
2762 * @buf: The buffer to place the result into
2763 * @size: The size of the buffer, including the trailing null space
2764 * @fmt: The format string to use
2765 * @...: Arguments for the format string
2766 *
2767 * The return value is the number of characters written into @buf not including
2768 * the trailing '\0'. If @size is == 0 the function returns 0.
2769 */
2770
2771 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2772 {
2773 va_list args;
2774 int i;
2775
2776 va_start(args, fmt);
2777 i = vscnprintf(buf, size, fmt, args);
2778 va_end(args);
2779
2780 return i;
2781 }
2782 EXPORT_SYMBOL(scnprintf);
2783
2784 /**
2785 * vsprintf - Format a string and place it in a buffer
2786 * @buf: The buffer to place the result into
2787 * @fmt: The format string to use
2788 * @args: Arguments for the format string
2789 *
2790 * The function returns the number of characters written
2791 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2792 * buffer overflows.
2793 *
2794 * If you're not already dealing with a va_list consider using sprintf().
2795 *
2796 * See the vsnprintf() documentation for format string extensions over C99.
2797 */
2798 int vsprintf(char *buf, const char *fmt, va_list args)
2799 {
2800 return vsnprintf(buf, INT_MAX, fmt, args);
2801 }
2802 EXPORT_SYMBOL(vsprintf);
2803
2804 /**
2805 * sprintf - Format a string and place it in a buffer
2806 * @buf: The buffer to place the result into
2807 * @fmt: The format string to use
2808 * @...: Arguments for the format string
2809 *
2810 * The function returns the number of characters written
2811 * into @buf. Use snprintf() or scnprintf() in order to avoid
2812 * buffer overflows.
2813 *
2814 * See the vsnprintf() documentation for format string extensions over C99.
2815 */
2816 int sprintf(char *buf, const char *fmt, ...)
2817 {
2818 va_list args;
2819 int i;
2820
2821 va_start(args, fmt);
2822 i = vsnprintf(buf, INT_MAX, fmt, args);
2823 va_end(args);
2824
2825 return i;
2826 }
2827 EXPORT_SYMBOL(sprintf);
2828
2829 #ifdef CONFIG_BINARY_PRINTF
2830 /*
2831 * bprintf service:
2832 * vbin_printf() - VA arguments to binary data
2833 * bstr_printf() - Binary data to text string
2834 */
2835
2836 /**
2837 * vbin_printf - Parse a format string and place args' binary value in a buffer
2838 * @bin_buf: The buffer to place args' binary value
2839 * @size: The size of the buffer(by words(32bits), not characters)
2840 * @fmt: The format string to use
2841 * @args: Arguments for the format string
2842 *
2843 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2844 * is skipped.
2845 *
2846 * The return value is the number of words(32bits) which would be generated for
2847 * the given input.
2848 *
2849 * NOTE:
2850 * If the return value is greater than @size, the resulting bin_buf is NOT
2851 * valid for bstr_printf().
2852 */
2853 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2854 {
2855 struct printf_spec spec = {0};
2856 char *str, *end;
2857 int width;
2858
2859 str = (char *)bin_buf;
2860 end = (char *)(bin_buf + size);
2861
2862 #define save_arg(type) \
2863 ({ \
2864 unsigned long long value; \
2865 if (sizeof(type) == 8) { \
2866 unsigned long long val8; \
2867 str = PTR_ALIGN(str, sizeof(u32)); \
2868 val8 = va_arg(args, unsigned long long); \
2869 if (str + sizeof(type) <= end) { \
2870 *(u32 *)str = *(u32 *)&val8; \
2871 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
2872 } \
2873 value = val8; \
2874 } else { \
2875 unsigned int val4; \
2876 str = PTR_ALIGN(str, sizeof(type)); \
2877 val4 = va_arg(args, int); \
2878 if (str + sizeof(type) <= end) \
2879 *(typeof(type) *)str = (type)(long)val4; \
2880 value = (unsigned long long)val4; \
2881 } \
2882 str += sizeof(type); \
2883 value; \
2884 })
2885
2886 while (*fmt) {
2887 int read = format_decode(fmt, &spec);
2888
2889 fmt += read;
2890
2891 switch (spec.type) {
2892 case FORMAT_TYPE_NONE:
2893 case FORMAT_TYPE_PERCENT_CHAR:
2894 break;
2895 case FORMAT_TYPE_INVALID:
2896 goto out;
2897
2898 case FORMAT_TYPE_WIDTH:
2899 case FORMAT_TYPE_PRECISION:
2900 width = (int)save_arg(int);
2901 /* Pointers may require the width */
2902 if (*fmt == 'p')
2903 set_field_width(&spec, width);
2904 break;
2905
2906 case FORMAT_TYPE_CHAR:
2907 save_arg(char);
2908 break;
2909
2910 case FORMAT_TYPE_STR: {
2911 const char *save_str = va_arg(args, char *);
2912 const char *err_msg;
2913 size_t len;
2914
2915 err_msg = check_pointer_msg(save_str);
2916 if (err_msg)
2917 save_str = err_msg;
2918
2919 len = strlen(save_str) + 1;
2920 if (str + len < end)
2921 memcpy(str, save_str, len);
2922 str += len;
2923 break;
2924 }
2925
2926 case FORMAT_TYPE_PTR:
2927 /* Dereferenced pointers must be done now */
2928 switch (*fmt) {
2929 /* Dereference of functions is still OK */
2930 case 'S':
2931 case 's':
2932 case 'x':
2933 case 'K':
2934 case 'e':
2935 save_arg(void *);
2936 break;
2937 default:
2938 if (!isalnum(*fmt)) {
2939 save_arg(void *);
2940 break;
2941 }
2942 str = pointer(fmt, str, end, va_arg(args, void *),
2943 spec);
2944 if (str + 1 < end)
2945 *str++ = '\0';
2946 else
2947 end[-1] = '\0'; /* Must be nul terminated */
2948 }
2949 /* skip all alphanumeric pointer suffixes */
2950 while (isalnum(*fmt))
2951 fmt++;
2952 break;
2953
2954 default:
2955 switch (spec.type) {
2956
2957 case FORMAT_TYPE_LONG_LONG:
2958 save_arg(long long);
2959 break;
2960 case FORMAT_TYPE_ULONG:
2961 case FORMAT_TYPE_LONG:
2962 save_arg(unsigned long);
2963 break;
2964 case FORMAT_TYPE_SIZE_T:
2965 save_arg(size_t);
2966 break;
2967 case FORMAT_TYPE_PTRDIFF:
2968 save_arg(ptrdiff_t);
2969 break;
2970 case FORMAT_TYPE_UBYTE:
2971 case FORMAT_TYPE_BYTE:
2972 save_arg(char);
2973 break;
2974 case FORMAT_TYPE_USHORT:
2975 case FORMAT_TYPE_SHORT:
2976 save_arg(short);
2977 break;
2978 default:
2979 save_arg(int);
2980 }
2981 }
2982 }
2983
2984 out:
2985 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2986 #undef save_arg
2987 }
2988 EXPORT_SYMBOL_GPL(vbin_printf);
2989
2990 /**
2991 * bstr_printf - Format a string from binary arguments and place it in a buffer
2992 * @buf: The buffer to place the result into
2993 * @size: The size of the buffer, including the trailing null space
2994 * @fmt: The format string to use
2995 * @bin_buf: Binary arguments for the format string
2996 *
2997 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2998 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2999 * a binary buffer that generated by vbin_printf.
3000 *
3001 * The format follows C99 vsnprintf, but has some extensions:
3002 * see vsnprintf comment for details.
3003 *
3004 * The return value is the number of characters which would
3005 * be generated for the given input, excluding the trailing
3006 * '\0', as per ISO C99. If you want to have the exact
3007 * number of characters written into @buf as return value
3008 * (not including the trailing '\0'), use vscnprintf(). If the
3009 * return is greater than or equal to @size, the resulting
3010 * string is truncated.
3011 */
3012 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
3013 {
3014 struct printf_spec spec = {0};
3015 char *str, *end;
3016 const char *args = (const char *)bin_buf;
3017
3018 if (WARN_ON_ONCE(size > INT_MAX))
3019 return 0;
3020
3021 str = buf;
3022 end = buf + size;
3023
3024 #define get_arg(type) \
3025 ({ \
3026 typeof(type) value; \
3027 if (sizeof(type) == 8) { \
3028 args = PTR_ALIGN(args, sizeof(u32)); \
3029 *(u32 *)&value = *(u32 *)args; \
3030 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
3031 } else { \
3032 args = PTR_ALIGN(args, sizeof(type)); \
3033 value = *(typeof(type) *)args; \
3034 } \
3035 args += sizeof(type); \
3036 value; \
3037 })
3038
3039 /* Make sure end is always >= buf */
3040 if (end < buf) {
3041 end = ((void *)-1);
3042 size = end - buf;
3043 }
3044
3045 while (*fmt) {
3046 const char *old_fmt = fmt;
3047 int read = format_decode(fmt, &spec);
3048
3049 fmt += read;
3050
3051 switch (spec.type) {
3052 case FORMAT_TYPE_NONE: {
3053 int copy = read;
3054 if (str < end) {
3055 if (copy > end - str)
3056 copy = end - str;
3057 memcpy(str, old_fmt, copy);
3058 }
3059 str += read;
3060 break;
3061 }
3062
3063 case FORMAT_TYPE_WIDTH:
3064 set_field_width(&spec, get_arg(int));
3065 break;
3066
3067 case FORMAT_TYPE_PRECISION:
3068 set_precision(&spec, get_arg(int));
3069 break;
3070
3071 case FORMAT_TYPE_CHAR: {
3072 char c;
3073
3074 if (!(spec.flags & LEFT)) {
3075 while (--spec.field_width > 0) {
3076 if (str < end)
3077 *str = ' ';
3078 ++str;
3079 }
3080 }
3081 c = (unsigned char) get_arg(char);
3082 if (str < end)
3083 *str = c;
3084 ++str;
3085 while (--spec.field_width > 0) {
3086 if (str < end)
3087 *str = ' ';
3088 ++str;
3089 }
3090 break;
3091 }
3092
3093 case FORMAT_TYPE_STR: {
3094 const char *str_arg = args;
3095 args += strlen(str_arg) + 1;
3096 str = string(str, end, (char *)str_arg, spec);
3097 break;
3098 }
3099
3100 case FORMAT_TYPE_PTR: {
3101 bool process = false;
3102 int copy, len;
3103 /* Non function dereferences were already done */
3104 switch (*fmt) {
3105 case 'S':
3106 case 's':
3107 case 'F':
3108 case 'f':
3109 case 'x':
3110 case 'K':
3111 case 'e':
3112 process = true;
3113 break;
3114 default:
3115 if (!isalnum(*fmt)) {
3116 process = true;
3117 break;
3118 }
3119 /* Pointer dereference was already processed */
3120 if (str < end) {
3121 len = copy = strlen(args);
3122 if (copy > end - str)
3123 copy = end - str;
3124 memcpy(str, args, copy);
3125 str += len;
3126 args += len + 1;
3127 }
3128 }
3129 if (process)
3130 str = pointer(fmt, str, end, get_arg(void *), spec);
3131
3132 while (isalnum(*fmt))
3133 fmt++;
3134 break;
3135 }
3136
3137 case FORMAT_TYPE_PERCENT_CHAR:
3138 if (str < end)
3139 *str = '%';
3140 ++str;
3141 break;
3142
3143 case FORMAT_TYPE_INVALID:
3144 goto out;
3145
3146 default: {
3147 unsigned long long num;
3148
3149 switch (spec.type) {
3150
3151 case FORMAT_TYPE_LONG_LONG:
3152 num = get_arg(long long);
3153 break;
3154 case FORMAT_TYPE_ULONG:
3155 case FORMAT_TYPE_LONG:
3156 num = get_arg(unsigned long);
3157 break;
3158 case FORMAT_TYPE_SIZE_T:
3159 num = get_arg(size_t);
3160 break;
3161 case FORMAT_TYPE_PTRDIFF:
3162 num = get_arg(ptrdiff_t);
3163 break;
3164 case FORMAT_TYPE_UBYTE:
3165 num = get_arg(unsigned char);
3166 break;
3167 case FORMAT_TYPE_BYTE:
3168 num = get_arg(signed char);
3169 break;
3170 case FORMAT_TYPE_USHORT:
3171 num = get_arg(unsigned short);
3172 break;
3173 case FORMAT_TYPE_SHORT:
3174 num = get_arg(short);
3175 break;
3176 case FORMAT_TYPE_UINT:
3177 num = get_arg(unsigned int);
3178 break;
3179 default:
3180 num = get_arg(int);
3181 }
3182
3183 str = number(str, end, num, spec);
3184 } /* default: */
3185 } /* switch(spec.type) */
3186 } /* while(*fmt) */
3187
3188 out:
3189 if (size > 0) {
3190 if (str < end)
3191 *str = '\0';
3192 else
3193 end[-1] = '\0';
3194 }
3195
3196 #undef get_arg
3197
3198 /* the trailing null byte doesn't count towards the total */
3199 return str - buf;
3200 }
3201 EXPORT_SYMBOL_GPL(bstr_printf);
3202
3203 /**
3204 * bprintf - Parse a format string and place args' binary value in a buffer
3205 * @bin_buf: The buffer to place args' binary value
3206 * @size: The size of the buffer(by words(32bits), not characters)
3207 * @fmt: The format string to use
3208 * @...: Arguments for the format string
3209 *
3210 * The function returns the number of words(u32) written
3211 * into @bin_buf.
3212 */
3213 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3214 {
3215 va_list args;
3216 int ret;
3217
3218 va_start(args, fmt);
3219 ret = vbin_printf(bin_buf, size, fmt, args);
3220 va_end(args);
3221
3222 return ret;
3223 }
3224 EXPORT_SYMBOL_GPL(bprintf);
3225
3226 #endif /* CONFIG_BINARY_PRINTF */
3227
3228 /**
3229 * vsscanf - Unformat a buffer into a list of arguments
3230 * @buf: input buffer
3231 * @fmt: format of buffer
3232 * @args: arguments
3233 */
3234 int vsscanf(const char *buf, const char *fmt, va_list args)
3235 {
3236 const char *str = buf;
3237 char *next;
3238 char digit;
3239 int num = 0;
3240 u8 qualifier;
3241 unsigned int base;
3242 union {
3243 long long s;
3244 unsigned long long u;
3245 } val;
3246 s16 field_width;
3247 bool is_sign;
3248
3249 while (*fmt) {
3250 /* skip any white space in format */
3251 /* white space in format matchs any amount of
3252 * white space, including none, in the input.
3253 */
3254 if (isspace(*fmt)) {
3255 fmt = skip_spaces(++fmt);
3256 str = skip_spaces(str);
3257 }
3258
3259 /* anything that is not a conversion must match exactly */
3260 if (*fmt != '%' && *fmt) {
3261 if (*fmt++ != *str++)
3262 break;
3263 continue;
3264 }
3265
3266 if (!*fmt)
3267 break;
3268 ++fmt;
3269
3270 /* skip this conversion.
3271 * advance both strings to next white space
3272 */
3273 if (*fmt == '*') {
3274 if (!*str)
3275 break;
3276 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3277 /* '%*[' not yet supported, invalid format */
3278 if (*fmt == '[')
3279 return num;
3280 fmt++;
3281 }
3282 while (!isspace(*str) && *str)
3283 str++;
3284 continue;
3285 }
3286
3287 /* get field width */
3288 field_width = -1;
3289 if (isdigit(*fmt)) {
3290 field_width = skip_atoi(&fmt);
3291 if (field_width <= 0)
3292 break;
3293 }
3294
3295 /* get conversion qualifier */
3296 qualifier = -1;
3297 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3298 *fmt == 'z') {
3299 qualifier = *fmt++;
3300 if (unlikely(qualifier == *fmt)) {
3301 if (qualifier == 'h') {
3302 qualifier = 'H';
3303 fmt++;
3304 } else if (qualifier == 'l') {
3305 qualifier = 'L';
3306 fmt++;
3307 }
3308 }
3309 }
3310
3311 if (!*fmt)
3312 break;
3313
3314 if (*fmt == 'n') {
3315 /* return number of characters read so far */
3316 *va_arg(args, int *) = str - buf;
3317 ++fmt;
3318 continue;
3319 }
3320
3321 if (!*str)
3322 break;
3323
3324 base = 10;
3325 is_sign = false;
3326
3327 switch (*fmt++) {
3328 case 'c':
3329 {
3330 char *s = (char *)va_arg(args, char*);
3331 if (field_width == -1)
3332 field_width = 1;
3333 do {
3334 *s++ = *str++;
3335 } while (--field_width > 0 && *str);
3336 num++;
3337 }
3338 continue;
3339 case 's':
3340 {
3341 char *s = (char *)va_arg(args, char *);
3342 if (field_width == -1)
3343 field_width = SHRT_MAX;
3344 /* first, skip leading white space in buffer */
3345 str = skip_spaces(str);
3346
3347 /* now copy until next white space */
3348 while (*str && !isspace(*str) && field_width--)
3349 *s++ = *str++;
3350 *s = '\0';
3351 num++;
3352 }
3353 continue;
3354 /*
3355 * Warning: This implementation of the '[' conversion specifier
3356 * deviates from its glibc counterpart in the following ways:
3357 * (1) It does NOT support ranges i.e. '-' is NOT a special
3358 * character
3359 * (2) It cannot match the closing bracket ']' itself
3360 * (3) A field width is required
3361 * (4) '%*[' (discard matching input) is currently not supported
3362 *
3363 * Example usage:
3364 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3365 * buf1, buf2, buf3);
3366 * if (ret < 3)
3367 * // etc..
3368 */
3369 case '[':
3370 {
3371 char *s = (char *)va_arg(args, char *);
3372 DECLARE_BITMAP(set, 256) = {0};
3373 unsigned int len = 0;
3374 bool negate = (*fmt == '^');
3375
3376 /* field width is required */
3377 if (field_width == -1)
3378 return num;
3379
3380 if (negate)
3381 ++fmt;
3382
3383 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3384 set_bit((u8)*fmt, set);
3385
3386 /* no ']' or no character set found */
3387 if (!*fmt || !len)
3388 return num;
3389 ++fmt;
3390
3391 if (negate) {
3392 bitmap_complement(set, set, 256);
3393 /* exclude null '\0' byte */
3394 clear_bit(0, set);
3395 }
3396
3397 /* match must be non-empty */
3398 if (!test_bit((u8)*str, set))
3399 return num;
3400
3401 while (test_bit((u8)*str, set) && field_width--)
3402 *s++ = *str++;
3403 *s = '\0';
3404 ++num;
3405 }
3406 continue;
3407 case 'o':
3408 base = 8;
3409 break;
3410 case 'x':
3411 case 'X':
3412 base = 16;
3413 break;
3414 case 'i':
3415 base = 0;
3416 /* fall through */
3417 case 'd':
3418 is_sign = true;
3419 /* fall through */
3420 case 'u':
3421 break;
3422 case '%':
3423 /* looking for '%' in str */
3424 if (*str++ != '%')
3425 return num;
3426 continue;
3427 default:
3428 /* invalid format; stop here */
3429 return num;
3430 }
3431
3432 /* have some sort of integer conversion.
3433 * first, skip white space in buffer.
3434 */
3435 str = skip_spaces(str);
3436
3437 digit = *str;
3438 if (is_sign && digit == '-')
3439 digit = *(str + 1);
3440
3441 if (!digit
3442 || (base == 16 && !isxdigit(digit))
3443 || (base == 10 && !isdigit(digit))
3444 || (base == 8 && (!isdigit(digit) || digit > '7'))
3445 || (base == 0 && !isdigit(digit)))
3446 break;
3447
3448 if (is_sign)
3449 val.s = qualifier != 'L' ?
3450 simple_strtol(str, &next, base) :
3451 simple_strtoll(str, &next, base);
3452 else
3453 val.u = qualifier != 'L' ?
3454 simple_strtoul(str, &next, base) :
3455 simple_strtoull(str, &next, base);
3456
3457 if (field_width > 0 && next - str > field_width) {
3458 if (base == 0)
3459 _parse_integer_fixup_radix(str, &base);
3460 while (next - str > field_width) {
3461 if (is_sign)
3462 val.s = div_s64(val.s, base);
3463 else
3464 val.u = div_u64(val.u, base);
3465 --next;
3466 }
3467 }
3468
3469 switch (qualifier) {
3470 case 'H': /* that's 'hh' in format */
3471 if (is_sign)
3472 *va_arg(args, signed char *) = val.s;
3473 else
3474 *va_arg(args, unsigned char *) = val.u;
3475 break;
3476 case 'h':
3477 if (is_sign)
3478 *va_arg(args, short *) = val.s;
3479 else
3480 *va_arg(args, unsigned short *) = val.u;
3481 break;
3482 case 'l':
3483 if (is_sign)
3484 *va_arg(args, long *) = val.s;
3485 else
3486 *va_arg(args, unsigned long *) = val.u;
3487 break;
3488 case 'L':
3489 if (is_sign)
3490 *va_arg(args, long long *) = val.s;
3491 else
3492 *va_arg(args, unsigned long long *) = val.u;
3493 break;
3494 case 'z':
3495 *va_arg(args, size_t *) = val.u;
3496 break;
3497 default:
3498 if (is_sign)
3499 *va_arg(args, int *) = val.s;
3500 else
3501 *va_arg(args, unsigned int *) = val.u;
3502 break;
3503 }
3504 num++;
3505
3506 if (!next)
3507 break;
3508 str = next;
3509 }
3510
3511 return num;
3512 }
3513 EXPORT_SYMBOL(vsscanf);
3514
3515 /**
3516 * sscanf - Unformat a buffer into a list of arguments
3517 * @buf: input buffer
3518 * @fmt: formatting of buffer
3519 * @...: resulting arguments
3520 */
3521 int sscanf(const char *buf, const char *fmt, ...)
3522 {
3523 va_list args;
3524 int i;
3525
3526 va_start(args, fmt);
3527 i = vsscanf(buf, fmt, args);
3528 va_end(args);
3529
3530 return i;
3531 }
3532 EXPORT_SYMBOL(sscanf);
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