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59 * This function is obsolete.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84 * This function is obsolete.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