xref: /openbsd-src/lib/libc/stdlib/malloc.c (revision df17eac1ea1e8b2c7a0e8b617aa2489684177147)
1 /*	$OpenBSD: malloc.c,v 1.265 2020/10/09 16:01:48 otto Exp $	*/
2 /*
3  * Copyright (c) 2008, 2010, 2011, 2016 Otto Moerbeek <otto@drijf.net>
4  * Copyright (c) 2012 Matthew Dempsky <matthew@openbsd.org>
5  * Copyright (c) 2008 Damien Miller <djm@openbsd.org>
6  * Copyright (c) 2000 Poul-Henning Kamp <phk@FreeBSD.org>
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 /*
22  * If we meet some day, and you think this stuff is worth it, you
23  * can buy me a beer in return. Poul-Henning Kamp
24  */
25 
26 /* #define MALLOC_STATS */
27 
28 #include <sys/types.h>
29 #include <sys/queue.h>
30 #include <sys/mman.h>
31 #include <sys/sysctl.h>
32 #include <uvm/uvmexp.h>
33 #include <errno.h>
34 #include <stdarg.h>
35 #include <stdint.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 
41 #ifdef MALLOC_STATS
42 #include <sys/tree.h>
43 #include <fcntl.h>
44 #endif
45 
46 #include "thread_private.h"
47 #include <tib.h>
48 
49 #define MALLOC_PAGESHIFT	_MAX_PAGE_SHIFT
50 
51 #define MALLOC_MINSHIFT		4
52 #define MALLOC_MAXSHIFT		(MALLOC_PAGESHIFT - 1)
53 #define MALLOC_PAGESIZE		(1UL << MALLOC_PAGESHIFT)
54 #define MALLOC_MINSIZE		(1UL << MALLOC_MINSHIFT)
55 #define MALLOC_PAGEMASK		(MALLOC_PAGESIZE - 1)
56 #define MASK_POINTER(p)		((void *)(((uintptr_t)(p)) & ~MALLOC_PAGEMASK))
57 
58 #define MALLOC_MAXCHUNK		(1 << MALLOC_MAXSHIFT)
59 #define MALLOC_MAXCACHE		256
60 #define MALLOC_DELAYED_CHUNK_MASK	15
61 #ifdef MALLOC_STATS
62 #define MALLOC_INITIAL_REGIONS	512
63 #else
64 #define MALLOC_INITIAL_REGIONS	(MALLOC_PAGESIZE / sizeof(struct region_info))
65 #endif
66 #define MALLOC_DEFAULT_CACHE	64
67 #define MALLOC_CHUNK_LISTS	4
68 #define CHUNK_CHECK_LENGTH	32
69 
70 /*
71  * We move allocations between half a page and a whole page towards the end,
72  * subject to alignment constraints. This is the extra headroom we allow.
73  * Set to zero to be the most strict.
74  */
75 #define MALLOC_LEEWAY		0
76 #define MALLOC_MOVE_COND(sz)	((sz) - mopts.malloc_guard < 		\
77 				    MALLOC_PAGESIZE - MALLOC_LEEWAY)
78 #define MALLOC_MOVE(p, sz)  	(((char *)(p)) +			\
79 				    ((MALLOC_PAGESIZE - MALLOC_LEEWAY -	\
80 			    	    ((sz) - mopts.malloc_guard)) & 	\
81 				    ~(MALLOC_MINSIZE - 1)))
82 
83 #define PAGEROUND(x)  (((x) + (MALLOC_PAGEMASK)) & ~MALLOC_PAGEMASK)
84 
85 /*
86  * What to use for Junk.  This is the byte value we use to fill with
87  * when the 'J' option is enabled. Use SOME_JUNK right after alloc,
88  * and SOME_FREEJUNK right before free.
89  */
90 #define SOME_JUNK		0xdb	/* deadbeef */
91 #define SOME_FREEJUNK		0xdf	/* dead, free */
92 
93 #define MMAP(sz,f)	mmap(NULL, (sz), PROT_READ | PROT_WRITE, \
94     MAP_ANON | MAP_PRIVATE | (f), -1, 0)
95 
96 #define MMAPNONE(sz,f)	mmap(NULL, (sz), PROT_NONE, \
97     MAP_ANON | MAP_PRIVATE | (f), -1, 0)
98 
99 #define MMAPA(a,sz,f)	mmap((a), (sz), PROT_READ | PROT_WRITE, \
100     MAP_ANON | MAP_PRIVATE | (f), -1, 0)
101 
102 #define MQUERY(a,sz,f)	mquery((a), (sz), PROT_READ | PROT_WRITE, \
103     MAP_ANON | MAP_PRIVATE | MAP_FIXED | (f), -1, 0)
104 
105 struct region_info {
106 	void *p;		/* page; low bits used to mark chunks */
107 	uintptr_t size;		/* size for pages, or chunk_info pointer */
108 #ifdef MALLOC_STATS
109 	void *f;		/* where allocated from */
110 #endif
111 };
112 
113 LIST_HEAD(chunk_head, chunk_info);
114 
115 struct dir_info {
116 	u_int32_t canary1;
117 	int active;			/* status of malloc */
118 	struct region_info *r;		/* region slots */
119 	size_t regions_total;		/* number of region slots */
120 	size_t regions_free;		/* number of free slots */
121 	size_t free_regions_size;	/* free pages cached */
122 	size_t rbytesused;		/* random bytes used */
123 	char *func;			/* current function */
124 	u_int malloc_cache;		/* # of free pages we cache */
125 	int malloc_junk;		/* junk fill? */
126 	int mmap_flag;			/* extra flag for mmap */
127 	u_int rotor;
128 	int mutex;
129 					/* lists of free chunk info structs */
130 	struct chunk_head chunk_info_list[MALLOC_MAXSHIFT + 1];
131 					/* lists of chunks with free slots */
132 	struct chunk_head chunk_dir[MALLOC_MAXSHIFT + 1][MALLOC_CHUNK_LISTS];
133 					/* free pages cache */
134 	struct region_info free_regions[MALLOC_MAXCACHE];
135 					/* delayed free chunk slots */
136 	void *delayed_chunks[MALLOC_DELAYED_CHUNK_MASK + 1];
137 	u_char rbytes[32];		/* random bytes */
138 #ifdef MALLOC_STATS
139 	size_t inserts;
140 	size_t insert_collisions;
141 	size_t finds;
142 	size_t find_collisions;
143 	size_t deletes;
144 	size_t delete_moves;
145 	size_t cheap_realloc_tries;
146 	size_t cheap_reallocs;
147 	size_t malloc_used;		/* bytes allocated */
148 	size_t malloc_guarded;		/* bytes used for guards */
149 	size_t pool_searches;		/* searches for pool */
150 	size_t other_pool;		/* searches in other pool */
151 #define STATS_ADD(x,y)	((x) += (y))
152 #define STATS_SUB(x,y)	((x) -= (y))
153 #define STATS_INC(x)	((x)++)
154 #define STATS_ZERO(x)	((x) = 0)
155 #define STATS_SETF(x,y)	((x)->f = (y))
156 #else
157 #define STATS_ADD(x,y)	/* nothing */
158 #define STATS_SUB(x,y)	/* nothing */
159 #define STATS_INC(x)	/* nothing */
160 #define STATS_ZERO(x)	/* nothing */
161 #define STATS_SETF(x,y)	/* nothing */
162 #endif /* MALLOC_STATS */
163 	u_int32_t canary2;
164 };
165 #define DIR_INFO_RSZ	((sizeof(struct dir_info) + MALLOC_PAGEMASK) & \
166 			~MALLOC_PAGEMASK)
167 
168 /*
169  * This structure describes a page worth of chunks.
170  *
171  * How many bits per u_short in the bitmap
172  */
173 #define MALLOC_BITS		(NBBY * sizeof(u_short))
174 struct chunk_info {
175 	LIST_ENTRY(chunk_info) entries;
176 	void *page;			/* pointer to the page */
177 	u_short canary;
178 	u_short size;			/* size of this page's chunks */
179 	u_short shift;			/* how far to shift for this size */
180 	u_short free;			/* how many free chunks */
181 	u_short total;			/* how many chunks */
182 	u_short offset;			/* requested size table offset */
183 	u_short bits[1];		/* which chunks are free */
184 };
185 
186 struct malloc_readonly {
187 					/* Main bookkeeping information */
188 	struct dir_info *malloc_pool[_MALLOC_MUTEXES];
189 	u_int	malloc_mutexes;		/* how much in actual use? */
190 	int	malloc_mt;		/* multi-threaded mode? */
191 	int	malloc_freecheck;	/* Extensive double free check */
192 	int	malloc_freeunmap;	/* mprotect free pages PROT_NONE? */
193 	int	def_malloc_junk;	/* junk fill? */
194 	int	malloc_realloc;		/* always realloc? */
195 	int	malloc_xmalloc;		/* xmalloc behaviour? */
196 	u_int	chunk_canaries;		/* use canaries after chunks? */
197 	int	internal_funcs;		/* use better recallocarray/freezero? */
198 	u_int	def_malloc_cache;	/* free pages we cache */
199 	size_t	malloc_guard;		/* use guard pages after allocations? */
200 #ifdef MALLOC_STATS
201 	int	malloc_stats;		/* dump statistics at end */
202 #endif
203 	u_int32_t malloc_canary;	/* Matched against ones in malloc_pool */
204 };
205 
206 /* This object is mapped PROT_READ after initialisation to prevent tampering */
207 static union {
208 	struct malloc_readonly mopts;
209 	u_char _pad[MALLOC_PAGESIZE];
210 } malloc_readonly __attribute__((aligned(MALLOC_PAGESIZE)));
211 #define mopts	malloc_readonly.mopts
212 
213 char		*malloc_options;	/* compile-time options */
214 
215 static __dead void wrterror(struct dir_info *d, char *msg, ...)
216     __attribute__((__format__ (printf, 2, 3)));
217 
218 #ifdef MALLOC_STATS
219 void malloc_dump(int, int, struct dir_info *);
220 PROTO_NORMAL(malloc_dump);
221 void malloc_gdump(int);
222 PROTO_NORMAL(malloc_gdump);
223 static void malloc_exit(void);
224 #define CALLER	__builtin_return_address(0)
225 #else
226 #define CALLER	NULL
227 #endif
228 
229 /* low bits of r->p determine size: 0 means >= page size and r->size holding
230  * real size, otherwise low bits are a shift count, or 1 for malloc(0)
231  */
232 #define REALSIZE(sz, r)						\
233 	(sz) = (uintptr_t)(r)->p & MALLOC_PAGEMASK,		\
234 	(sz) = ((sz) == 0 ? (r)->size : ((sz) == 1 ? 0 : (1 << ((sz)-1))))
235 
236 static inline void
237 _MALLOC_LEAVE(struct dir_info *d)
238 {
239 	if (mopts.malloc_mt) {
240 		d->active--;
241 		_MALLOC_UNLOCK(d->mutex);
242 	}
243 }
244 
245 static inline void
246 _MALLOC_ENTER(struct dir_info *d)
247 {
248 	if (mopts.malloc_mt) {
249 		_MALLOC_LOCK(d->mutex);
250 		d->active++;
251 	}
252 }
253 
254 static inline size_t
255 hash(void *p)
256 {
257 	size_t sum;
258 	uintptr_t u;
259 
260 	u = (uintptr_t)p >> MALLOC_PAGESHIFT;
261 	sum = u;
262 	sum = (sum << 7) - sum + (u >> 16);
263 #ifdef __LP64__
264 	sum = (sum << 7) - sum + (u >> 32);
265 	sum = (sum << 7) - sum + (u >> 48);
266 #endif
267 	return sum;
268 }
269 
270 static inline struct dir_info *
271 getpool(void)
272 {
273 	if (!mopts.malloc_mt)
274 		return mopts.malloc_pool[1];
275 	else	/* first one reserved for special pool */
276 		return mopts.malloc_pool[1 + TIB_GET()->tib_tid %
277 		    (mopts.malloc_mutexes - 1)];
278 }
279 
280 static __dead void
281 wrterror(struct dir_info *d, char *msg, ...)
282 {
283 	int		saved_errno = errno;
284 	va_list		ap;
285 
286 	dprintf(STDERR_FILENO, "%s(%d) in %s(): ", __progname,
287 	    getpid(), (d != NULL && d->func) ? d->func : "unknown");
288 	va_start(ap, msg);
289 	vdprintf(STDERR_FILENO, msg, ap);
290 	va_end(ap);
291 	dprintf(STDERR_FILENO, "\n");
292 
293 #ifdef MALLOC_STATS
294 	if (mopts.malloc_stats)
295 		malloc_gdump(STDERR_FILENO);
296 #endif /* MALLOC_STATS */
297 
298 	errno = saved_errno;
299 
300 	abort();
301 }
302 
303 static void
304 rbytes_init(struct dir_info *d)
305 {
306 	arc4random_buf(d->rbytes, sizeof(d->rbytes));
307 	/* add 1 to account for using d->rbytes[0] */
308 	d->rbytesused = 1 + d->rbytes[0] % (sizeof(d->rbytes) / 2);
309 }
310 
311 static inline u_char
312 getrbyte(struct dir_info *d)
313 {
314 	u_char x;
315 
316 	if (d->rbytesused >= sizeof(d->rbytes))
317 		rbytes_init(d);
318 	x = d->rbytes[d->rbytesused++];
319 	return x;
320 }
321 
322 static void
323 omalloc_parseopt(char opt)
324 {
325 	switch (opt) {
326 	case '+':
327 		mopts.malloc_mutexes <<= 1;
328 		if (mopts.malloc_mutexes > _MALLOC_MUTEXES)
329 			mopts.malloc_mutexes = _MALLOC_MUTEXES;
330 		break;
331 	case '-':
332 		mopts.malloc_mutexes >>= 1;
333 		if (mopts.malloc_mutexes < 2)
334 			mopts.malloc_mutexes = 2;
335 		break;
336 	case '>':
337 		mopts.def_malloc_cache <<= 1;
338 		if (mopts.def_malloc_cache > MALLOC_MAXCACHE)
339 			mopts.def_malloc_cache = MALLOC_MAXCACHE;
340 		break;
341 	case '<':
342 		mopts.def_malloc_cache >>= 1;
343 		break;
344 	case 'c':
345 		mopts.chunk_canaries = 0;
346 		break;
347 	case 'C':
348 		mopts.chunk_canaries = 1;
349 		break;
350 #ifdef MALLOC_STATS
351 	case 'd':
352 		mopts.malloc_stats = 0;
353 		break;
354 	case 'D':
355 		mopts.malloc_stats = 1;
356 		break;
357 #endif /* MALLOC_STATS */
358 	case 'f':
359 		mopts.malloc_freecheck = 0;
360 		mopts.malloc_freeunmap = 0;
361 		break;
362 	case 'F':
363 		mopts.malloc_freecheck = 1;
364 		mopts.malloc_freeunmap = 1;
365 		break;
366 	case 'g':
367 		mopts.malloc_guard = 0;
368 		break;
369 	case 'G':
370 		mopts.malloc_guard = MALLOC_PAGESIZE;
371 		break;
372 	case 'j':
373 		if (mopts.def_malloc_junk > 0)
374 			mopts.def_malloc_junk--;
375 		break;
376 	case 'J':
377 		if (mopts.def_malloc_junk < 2)
378 			mopts.def_malloc_junk++;
379 		break;
380 	case 'r':
381 		mopts.malloc_realloc = 0;
382 		break;
383 	case 'R':
384 		mopts.malloc_realloc = 1;
385 		break;
386 	case 'u':
387 		mopts.malloc_freeunmap = 0;
388 		break;
389 	case 'U':
390 		mopts.malloc_freeunmap = 1;
391 		break;
392 	case 'x':
393 		mopts.malloc_xmalloc = 0;
394 		break;
395 	case 'X':
396 		mopts.malloc_xmalloc = 1;
397 		break;
398 	default:
399 		dprintf(STDERR_FILENO, "malloc() warning: "
400                     "unknown char in MALLOC_OPTIONS\n");
401 		break;
402 	}
403 }
404 
405 static void
406 omalloc_init(void)
407 {
408 	char *p, *q, b[16];
409 	int i, j, mib[2];
410 	size_t sb;
411 
412 	/*
413 	 * Default options
414 	 */
415 	mopts.malloc_mutexes = 8;
416 	mopts.def_malloc_junk = 1;
417 	mopts.def_malloc_cache = MALLOC_DEFAULT_CACHE;
418 
419 	for (i = 0; i < 3; i++) {
420 		switch (i) {
421 		case 0:
422 			mib[0] = CTL_VM;
423 			mib[1] = VM_MALLOC_CONF;
424 			sb = sizeof(b);
425 			j = sysctl(mib, 2, b, &sb, NULL, 0);
426 			if (j != 0)
427 				continue;
428 			p = b;
429 			break;
430 		case 1:
431 			if (issetugid() == 0)
432 				p = getenv("MALLOC_OPTIONS");
433 			else
434 				continue;
435 			break;
436 		case 2:
437 			p = malloc_options;
438 			break;
439 		default:
440 			p = NULL;
441 		}
442 
443 		for (; p != NULL && *p != '\0'; p++) {
444 			switch (*p) {
445 			case 'S':
446 				for (q = "CFGJ"; *q != '\0'; q++)
447 					omalloc_parseopt(*q);
448 				mopts.def_malloc_cache = 0;
449 				break;
450 			case 's':
451 				for (q = "cfgj"; *q != '\0'; q++)
452 					omalloc_parseopt(*q);
453 				mopts.def_malloc_cache = MALLOC_DEFAULT_CACHE;
454 				break;
455 			default:
456 				omalloc_parseopt(*p);
457 				break;
458 			}
459 		}
460 	}
461 
462 #ifdef MALLOC_STATS
463 	if (mopts.malloc_stats && (atexit(malloc_exit) == -1)) {
464 		dprintf(STDERR_FILENO, "malloc() warning: atexit(2) failed."
465 		    " Will not be able to dump stats on exit\n");
466 	}
467 #endif /* MALLOC_STATS */
468 
469 	while ((mopts.malloc_canary = arc4random()) == 0)
470 		;
471 	if (mopts.chunk_canaries)
472 		do {
473 			mopts.chunk_canaries = arc4random();
474 		} while ((u_char)mopts.chunk_canaries == 0 ||
475 		    (u_char)mopts.chunk_canaries == SOME_FREEJUNK);
476 }
477 
478 static void
479 omalloc_poolinit(struct dir_info **dp, int mmap_flag)
480 {
481 	char *p;
482 	size_t d_avail, regioninfo_size;
483 	struct dir_info *d;
484 	int i, j;
485 
486 	/*
487 	 * Allocate dir_info with a guard page on either side. Also
488 	 * randomise offset inside the page at which the dir_info
489 	 * lies (subject to alignment by 1 << MALLOC_MINSHIFT)
490 	 */
491 	if ((p = MMAPNONE(DIR_INFO_RSZ + (MALLOC_PAGESIZE * 2), mmap_flag)) ==
492 	    MAP_FAILED)
493 		wrterror(NULL, "malloc init mmap failed");
494 	mprotect(p + MALLOC_PAGESIZE, DIR_INFO_RSZ, PROT_READ | PROT_WRITE);
495 	d_avail = (DIR_INFO_RSZ - sizeof(*d)) >> MALLOC_MINSHIFT;
496 	d = (struct dir_info *)(p + MALLOC_PAGESIZE +
497 	    (arc4random_uniform(d_avail) << MALLOC_MINSHIFT));
498 
499 	rbytes_init(d);
500 	d->regions_free = d->regions_total = MALLOC_INITIAL_REGIONS;
501 	regioninfo_size = d->regions_total * sizeof(struct region_info);
502 	d->r = MMAP(regioninfo_size, mmap_flag);
503 	if (d->r == MAP_FAILED) {
504 		d->regions_total = 0;
505 		wrterror(NULL, "malloc init mmap failed");
506 	}
507 	for (i = 0; i <= MALLOC_MAXSHIFT; i++) {
508 		LIST_INIT(&d->chunk_info_list[i]);
509 		for (j = 0; j < MALLOC_CHUNK_LISTS; j++)
510 			LIST_INIT(&d->chunk_dir[i][j]);
511 	}
512 	STATS_ADD(d->malloc_used, regioninfo_size + 3 * MALLOC_PAGESIZE);
513 	d->mmap_flag = mmap_flag;
514 	d->malloc_junk = mopts.def_malloc_junk;
515 	d->malloc_cache = mopts.def_malloc_cache;
516 	d->canary1 = mopts.malloc_canary ^ (u_int32_t)(uintptr_t)d;
517 	d->canary2 = ~d->canary1;
518 
519 	*dp = d;
520 }
521 
522 static int
523 omalloc_grow(struct dir_info *d)
524 {
525 	size_t newtotal;
526 	size_t newsize;
527 	size_t mask;
528 	size_t i;
529 	struct region_info *p;
530 
531 	if (d->regions_total > SIZE_MAX / sizeof(struct region_info) / 2)
532 		return 1;
533 
534 	newtotal = d->regions_total * 2;
535 	newsize = newtotal * sizeof(struct region_info);
536 	mask = newtotal - 1;
537 
538 	p = MMAP(newsize, d->mmap_flag);
539 	if (p == MAP_FAILED)
540 		return 1;
541 
542 	STATS_ADD(d->malloc_used, newsize);
543 	STATS_ZERO(d->inserts);
544 	STATS_ZERO(d->insert_collisions);
545 	for (i = 0; i < d->regions_total; i++) {
546 		void *q = d->r[i].p;
547 		if (q != NULL) {
548 			size_t index = hash(q) & mask;
549 			STATS_INC(d->inserts);
550 			while (p[index].p != NULL) {
551 				index = (index - 1) & mask;
552 				STATS_INC(d->insert_collisions);
553 			}
554 			p[index] = d->r[i];
555 		}
556 	}
557 	/* avoid pages containing meta info to end up in cache */
558 	if (munmap(d->r, d->regions_total * sizeof(struct region_info)))
559 		wrterror(d, "munmap %p", (void *)d->r);
560 	else
561 		STATS_SUB(d->malloc_used,
562 		    d->regions_total * sizeof(struct region_info));
563 	d->regions_free = d->regions_free + d->regions_total;
564 	d->regions_total = newtotal;
565 	d->r = p;
566 	return 0;
567 }
568 
569 /*
570  * The hashtable uses the assumption that p is never NULL. This holds since
571  * non-MAP_FIXED mappings with hint 0 start at BRKSIZ.
572  */
573 static int
574 insert(struct dir_info *d, void *p, size_t sz, void *f)
575 {
576 	size_t index;
577 	size_t mask;
578 	void *q;
579 
580 	if (d->regions_free * 4 < d->regions_total) {
581 		if (omalloc_grow(d))
582 			return 1;
583 	}
584 	mask = d->regions_total - 1;
585 	index = hash(p) & mask;
586 	q = d->r[index].p;
587 	STATS_INC(d->inserts);
588 	while (q != NULL) {
589 		index = (index - 1) & mask;
590 		q = d->r[index].p;
591 		STATS_INC(d->insert_collisions);
592 	}
593 	d->r[index].p = p;
594 	d->r[index].size = sz;
595 #ifdef MALLOC_STATS
596 	d->r[index].f = f;
597 #endif
598 	d->regions_free--;
599 	return 0;
600 }
601 
602 static struct region_info *
603 find(struct dir_info *d, void *p)
604 {
605 	size_t index;
606 	size_t mask = d->regions_total - 1;
607 	void *q, *r;
608 
609 	if (mopts.malloc_canary != (d->canary1 ^ (u_int32_t)(uintptr_t)d) ||
610 	    d->canary1 != ~d->canary2)
611 		wrterror(d, "internal struct corrupt");
612 	p = MASK_POINTER(p);
613 	index = hash(p) & mask;
614 	r = d->r[index].p;
615 	q = MASK_POINTER(r);
616 	STATS_INC(d->finds);
617 	while (q != p && r != NULL) {
618 		index = (index - 1) & mask;
619 		r = d->r[index].p;
620 		q = MASK_POINTER(r);
621 		STATS_INC(d->find_collisions);
622 	}
623 	return (q == p && r != NULL) ? &d->r[index] : NULL;
624 }
625 
626 static void
627 delete(struct dir_info *d, struct region_info *ri)
628 {
629 	/* algorithm R, Knuth Vol III section 6.4 */
630 	size_t mask = d->regions_total - 1;
631 	size_t i, j, r;
632 
633 	if (d->regions_total & (d->regions_total - 1))
634 		wrterror(d, "regions_total not 2^x");
635 	d->regions_free++;
636 	STATS_INC(d->deletes);
637 
638 	i = ri - d->r;
639 	for (;;) {
640 		d->r[i].p = NULL;
641 		d->r[i].size = 0;
642 		j = i;
643 		for (;;) {
644 			i = (i - 1) & mask;
645 			if (d->r[i].p == NULL)
646 				return;
647 			r = hash(d->r[i].p) & mask;
648 			if ((i <= r && r < j) || (r < j && j < i) ||
649 			    (j < i && i <= r))
650 				continue;
651 			d->r[j] = d->r[i];
652 			STATS_INC(d->delete_moves);
653 			break;
654 		}
655 
656 	}
657 }
658 
659 /*
660  * Cache maintenance. We keep at most malloc_cache pages cached.
661  * If the cache is becoming full, unmap pages in the cache for real,
662  * and then add the region to the cache
663  * Opposed to the regular region data structure, the sizes in the
664  * cache are in MALLOC_PAGESIZE units.
665  */
666 static void
667 unmap(struct dir_info *d, void *p, size_t sz, size_t clear, int junk)
668 {
669 	size_t psz = sz >> MALLOC_PAGESHIFT;
670 	size_t rsz;
671 	struct region_info *r;
672 	u_int i, offset, mask;
673 
674 	if (sz != PAGEROUND(sz))
675 		wrterror(d, "munmap round");
676 
677 	rsz = d->malloc_cache - d->free_regions_size;
678 
679 	/*
680 	 * normally the cache holds recently freed regions, but if the region
681 	 * to unmap is larger than the cache size or we're clearing and the
682 	 * cache is full, just munmap
683 	 */
684 	if (psz > d->malloc_cache || (clear > 0 && rsz == 0)) {
685 		i = munmap(p, sz);
686 		if (i)
687 			wrterror(d, "munmap %p", p);
688 		STATS_SUB(d->malloc_used, sz);
689 		return;
690 	}
691 	offset = getrbyte(d);
692 	mask = d->malloc_cache - 1;
693 	if (psz > rsz) {
694 		size_t tounmap = psz - rsz;
695 		for (i = 0; ; i++) {
696 			r = &d->free_regions[(i + offset) & mask];
697 			if (r->p != NULL) {
698 				rsz = r->size << MALLOC_PAGESHIFT;
699 				if (munmap(r->p, rsz))
700 					wrterror(d, "munmap %p", r->p);
701 				r->p = NULL;
702 				if (tounmap > r->size)
703 					tounmap -= r->size;
704 				else
705 					tounmap = 0;
706 				d->free_regions_size -= r->size;
707 				STATS_SUB(d->malloc_used, rsz);
708 				if (tounmap == 0) {
709 					offset = i;
710 					break;
711 				}
712 			}
713 		}
714 	}
715 	for (i = 0; ; i++) {
716 		r = &d->free_regions[(i + offset) & mask];
717 		if (r->p == NULL) {
718 			if (clear > 0)
719 				memset(p, 0, clear);
720 			if (junk && !mopts.malloc_freeunmap) {
721 				size_t amt = junk == 1 ?  MALLOC_MAXCHUNK : sz;
722 				memset(p, SOME_FREEJUNK, amt);
723 			}
724 			if (mopts.malloc_freeunmap)
725 				mprotect(p, sz, PROT_NONE);
726 			r->p = p;
727 			r->size = psz;
728 			d->free_regions_size += psz;
729 			break;
730 		}
731 	}
732 	if (d->free_regions_size > d->malloc_cache)
733 		wrterror(d, "malloc cache overflow");
734 }
735 
736 static void *
737 map(struct dir_info *d, size_t sz, int zero_fill)
738 {
739 	size_t psz = sz >> MALLOC_PAGESHIFT;
740 	struct region_info *r, *big = NULL;
741 	u_int i;
742 	void *p;
743 
744 	if (mopts.malloc_canary != (d->canary1 ^ (u_int32_t)(uintptr_t)d) ||
745 	    d->canary1 != ~d->canary2)
746 		wrterror(d, "internal struct corrupt");
747 	if (sz != PAGEROUND(sz))
748 		wrterror(d, "map round");
749 
750 	if (psz > d->free_regions_size) {
751 		_MALLOC_LEAVE(d);
752 		p = MMAP(sz, d->mmap_flag);
753 		_MALLOC_ENTER(d);
754 		if (p != MAP_FAILED)
755 			STATS_ADD(d->malloc_used, sz);
756 		/* zero fill not needed */
757 		return p;
758 	}
759 	for (i = 0; i < d->malloc_cache; i++) {
760 		r = &d->free_regions[(i + d->rotor) & (d->malloc_cache - 1)];
761 		if (r->p != NULL) {
762 			if (r->size == psz) {
763 				p = r->p;
764 				r->p = NULL;
765 				d->free_regions_size -= psz;
766 				if (mopts.malloc_freeunmap)
767 					mprotect(p, sz, PROT_READ | PROT_WRITE);
768 				if (zero_fill)
769 					memset(p, 0, sz);
770 				else if (d->malloc_junk == 2 &&
771 				    mopts.malloc_freeunmap)
772 					memset(p, SOME_FREEJUNK, sz);
773 				d->rotor += i + 1;
774 				return p;
775 			} else if (r->size > psz)
776 				big = r;
777 		}
778 	}
779 	if (big != NULL) {
780 		r = big;
781 		p = r->p;
782 		r->p = (char *)r->p + (psz << MALLOC_PAGESHIFT);
783 		if (mopts.malloc_freeunmap)
784 			mprotect(p, sz, PROT_READ | PROT_WRITE);
785 		r->size -= psz;
786 		d->free_regions_size -= psz;
787 		if (zero_fill)
788 			memset(p, 0, sz);
789 		else if (d->malloc_junk == 2 && mopts.malloc_freeunmap)
790 			memset(p, SOME_FREEJUNK, sz);
791 		return p;
792 	}
793 	if (d->free_regions_size > d->malloc_cache)
794 		wrterror(d, "malloc cache");
795 	_MALLOC_LEAVE(d);
796 	p = MMAP(sz, d->mmap_flag);
797 	_MALLOC_ENTER(d);
798 	if (p != MAP_FAILED)
799 		STATS_ADD(d->malloc_used, sz);
800 	/* zero fill not needed */
801 	return p;
802 }
803 
804 static void
805 init_chunk_info(struct dir_info *d, struct chunk_info *p, int bits)
806 {
807 	int i;
808 
809 	if (bits == 0) {
810 		p->shift = MALLOC_MINSHIFT;
811 		p->total = p->free = MALLOC_PAGESIZE >> p->shift;
812 		p->size = 0;
813 		p->offset = 0xdead;
814 	} else {
815 		p->shift = bits;
816 		p->total = p->free = MALLOC_PAGESIZE >> p->shift;
817 		p->size = 1U << bits;
818 		p->offset = howmany(p->total, MALLOC_BITS);
819 	}
820 	p->canary = (u_short)d->canary1;
821 
822 	/* set all valid bits in the bitmap */
823  	i = p->total - 1;
824 	memset(p->bits, 0xff, sizeof(p->bits[0]) * (i / MALLOC_BITS));
825 	p->bits[i / MALLOC_BITS] = (2U << (i % MALLOC_BITS)) - 1;
826 }
827 
828 static struct chunk_info *
829 alloc_chunk_info(struct dir_info *d, int bits)
830 {
831 	struct chunk_info *p;
832 
833 	if (LIST_EMPTY(&d->chunk_info_list[bits])) {
834 		size_t size, count, i;
835 		char *q;
836 
837 		if (bits == 0)
838 			count = MALLOC_PAGESIZE / MALLOC_MINSIZE;
839 		else
840 			count = MALLOC_PAGESIZE >> bits;
841 
842 		size = howmany(count, MALLOC_BITS);
843 		size = sizeof(struct chunk_info) + (size - 1) * sizeof(u_short);
844 		if (mopts.chunk_canaries)
845 			size += count * sizeof(u_short);
846 		size = _ALIGN(size);
847 
848 		q = MMAP(MALLOC_PAGESIZE, d->mmap_flag);
849 		if (q == MAP_FAILED)
850 			return NULL;
851 		STATS_ADD(d->malloc_used, MALLOC_PAGESIZE);
852 		count = MALLOC_PAGESIZE / size;
853 
854 		for (i = 0; i < count; i++, q += size) {
855 			p = (struct chunk_info *)q;
856 			LIST_INSERT_HEAD(&d->chunk_info_list[bits], p, entries);
857 		}
858 	}
859 	p = LIST_FIRST(&d->chunk_info_list[bits]);
860 	LIST_REMOVE(p, entries);
861 	if (p->shift == 0)
862 		init_chunk_info(d, p, bits);
863 	return p;
864 }
865 
866 /*
867  * Allocate a page of chunks
868  */
869 static struct chunk_info *
870 omalloc_make_chunks(struct dir_info *d, int bits, int listnum)
871 {
872 	struct chunk_info *bp;
873 	void *pp;
874 
875 	/* Allocate a new bucket */
876 	pp = map(d, MALLOC_PAGESIZE, 0);
877 	if (pp == MAP_FAILED)
878 		return NULL;
879 
880 	/* memory protect the page allocated in the malloc(0) case */
881 	if (bits == 0 && mprotect(pp, MALLOC_PAGESIZE, PROT_NONE) == -1)
882 		goto err;
883 
884 	bp = alloc_chunk_info(d, bits);
885 	if (bp == NULL)
886 		goto err;
887 	bp->page = pp;
888 
889 	if (insert(d, (void *)((uintptr_t)pp | (bits + 1)), (uintptr_t)bp,
890 	    NULL))
891 		goto err;
892 	LIST_INSERT_HEAD(&d->chunk_dir[bits][listnum], bp, entries);
893 	return bp;
894 
895 err:
896 	unmap(d, pp, MALLOC_PAGESIZE, 0, d->malloc_junk);
897 	return NULL;
898 }
899 
900 static int
901 find_chunksize(size_t size)
902 {
903 	int r;
904 
905 	/* malloc(0) is special */
906 	if (size == 0)
907 		return 0;
908 
909 	if (size < MALLOC_MINSIZE)
910 		size = MALLOC_MINSIZE;
911 	size--;
912 
913 	r = MALLOC_MINSHIFT;
914 	while (size >> r)
915 		r++;
916 	return r;
917 }
918 
919 static void
920 fill_canary(char *ptr, size_t sz, size_t allocated)
921 {
922 	size_t check_sz = allocated - sz;
923 
924 	if (check_sz > CHUNK_CHECK_LENGTH)
925 		check_sz = CHUNK_CHECK_LENGTH;
926 	memset(ptr + sz, mopts.chunk_canaries, check_sz);
927 }
928 
929 /*
930  * Allocate a chunk
931  */
932 static void *
933 malloc_bytes(struct dir_info *d, size_t size, void *f)
934 {
935 	u_int i, r;
936 	int j, listnum;
937 	size_t k;
938 	u_short	*lp;
939 	struct chunk_info *bp;
940 	void *p;
941 
942 	if (mopts.malloc_canary != (d->canary1 ^ (u_int32_t)(uintptr_t)d) ||
943 	    d->canary1 != ~d->canary2)
944 		wrterror(d, "internal struct corrupt");
945 
946 	j = find_chunksize(size);
947 
948 	r = ((u_int)getrbyte(d) << 8) | getrbyte(d);
949 	listnum = r % MALLOC_CHUNK_LISTS;
950 	/* If it's empty, make a page more of that size chunks */
951 	if ((bp = LIST_FIRST(&d->chunk_dir[j][listnum])) == NULL) {
952 		bp = omalloc_make_chunks(d, j, listnum);
953 		if (bp == NULL)
954 			return NULL;
955 	}
956 
957 	if (bp->canary != (u_short)d->canary1)
958 		wrterror(d, "chunk info corrupted");
959 
960 	i = (r / MALLOC_CHUNK_LISTS) & (bp->total - 1);
961 
962 	/* start somewhere in a short */
963 	lp = &bp->bits[i / MALLOC_BITS];
964 	if (*lp) {
965 		j = i % MALLOC_BITS;
966 		k = ffs(*lp >> j);
967 		if (k != 0) {
968 			k += j - 1;
969 			goto found;
970 		}
971 	}
972 	/* no bit halfway, go to next full short */
973 	i /= MALLOC_BITS;
974 	for (;;) {
975 		if (++i >= bp->total / MALLOC_BITS)
976 			i = 0;
977 		lp = &bp->bits[i];
978 		if (*lp) {
979 			k = ffs(*lp) - 1;
980 			break;
981 		}
982 	}
983 found:
984 #ifdef MALLOC_STATS
985 	if (i == 0 && k == 0) {
986 		struct region_info *r = find(d, bp->page);
987 		r->f = f;
988 	}
989 #endif
990 
991 	*lp ^= 1 << k;
992 
993 	/* If there are no more free, remove from free-list */
994 	if (--bp->free == 0)
995 		LIST_REMOVE(bp, entries);
996 
997 	/* Adjust to the real offset of that chunk */
998 	k += (lp - bp->bits) * MALLOC_BITS;
999 
1000 	if (mopts.chunk_canaries && size > 0)
1001 		bp->bits[bp->offset + k] = size;
1002 
1003 	k <<= bp->shift;
1004 
1005 	p = (char *)bp->page + k;
1006 	if (bp->size > 0) {
1007 		if (d->malloc_junk == 2)
1008 			memset(p, SOME_JUNK, bp->size);
1009 		else if (mopts.chunk_canaries)
1010 			fill_canary(p, size, bp->size);
1011 	}
1012 	return p;
1013 }
1014 
1015 static void
1016 validate_canary(struct dir_info *d, u_char *ptr, size_t sz, size_t allocated)
1017 {
1018 	size_t check_sz = allocated - sz;
1019 	u_char *p, *q;
1020 
1021 	if (check_sz > CHUNK_CHECK_LENGTH)
1022 		check_sz = CHUNK_CHECK_LENGTH;
1023 	p = ptr + sz;
1024 	q = p + check_sz;
1025 
1026 	while (p < q) {
1027 		if (*p != (u_char)mopts.chunk_canaries && *p != SOME_JUNK) {
1028 			wrterror(d, "chunk canary corrupted %p %#tx@%#zx%s",
1029 			    ptr, p - ptr, sz,
1030 			    *p == SOME_FREEJUNK ? " (double free?)" : "");
1031 		}
1032 		p++;
1033 	}
1034 }
1035 
1036 static uint32_t
1037 find_chunknum(struct dir_info *d, struct chunk_info *info, void *ptr, int check)
1038 {
1039 	uint32_t chunknum;
1040 
1041 	if (info->canary != (u_short)d->canary1)
1042 		wrterror(d, "chunk info corrupted");
1043 
1044 	/* Find the chunk number on the page */
1045 	chunknum = ((uintptr_t)ptr & MALLOC_PAGEMASK) >> info->shift;
1046 
1047 	if ((uintptr_t)ptr & ((1U << (info->shift)) - 1))
1048 		wrterror(d, "modified chunk-pointer %p", ptr);
1049 	if (info->bits[chunknum / MALLOC_BITS] &
1050 	    (1U << (chunknum % MALLOC_BITS)))
1051 		wrterror(d, "chunk is already free %p", ptr);
1052 	if (check && info->size > 0) {
1053 		validate_canary(d, ptr, info->bits[info->offset + chunknum],
1054 		    info->size);
1055 	}
1056 	return chunknum;
1057 }
1058 
1059 /*
1060  * Free a chunk, and possibly the page it's on, if the page becomes empty.
1061  */
1062 static void
1063 free_bytes(struct dir_info *d, struct region_info *r, void *ptr)
1064 {
1065 	struct chunk_head *mp;
1066 	struct chunk_info *info;
1067 	uint32_t chunknum;
1068 	int listnum;
1069 
1070 	info = (struct chunk_info *)r->size;
1071 	chunknum = find_chunknum(d, info, ptr, 0);
1072 
1073 	info->bits[chunknum / MALLOC_BITS] |= 1U << (chunknum % MALLOC_BITS);
1074 	info->free++;
1075 
1076 	if (info->free == 1) {
1077 		/* Page became non-full */
1078 		listnum = getrbyte(d) % MALLOC_CHUNK_LISTS;
1079 		if (info->size != 0)
1080 			mp = &d->chunk_dir[info->shift][listnum];
1081 		else
1082 			mp = &d->chunk_dir[0][listnum];
1083 
1084 		LIST_INSERT_HEAD(mp, info, entries);
1085 		return;
1086 	}
1087 
1088 	if (info->free != info->total)
1089 		return;
1090 
1091 	LIST_REMOVE(info, entries);
1092 
1093 	if (info->size == 0 && !mopts.malloc_freeunmap)
1094 		mprotect(info->page, MALLOC_PAGESIZE, PROT_READ | PROT_WRITE);
1095 	unmap(d, info->page, MALLOC_PAGESIZE, 0, 0);
1096 
1097 	delete(d, r);
1098 	if (info->size != 0)
1099 		mp = &d->chunk_info_list[info->shift];
1100 	else
1101 		mp = &d->chunk_info_list[0];
1102 	LIST_INSERT_HEAD(mp, info, entries);
1103 }
1104 
1105 
1106 
1107 static void *
1108 omalloc(struct dir_info *pool, size_t sz, int zero_fill, void *f)
1109 {
1110 	void *p;
1111 	size_t psz;
1112 
1113 	if (sz > MALLOC_MAXCHUNK) {
1114 		if (sz >= SIZE_MAX - mopts.malloc_guard - MALLOC_PAGESIZE) {
1115 			errno = ENOMEM;
1116 			return NULL;
1117 		}
1118 		sz += mopts.malloc_guard;
1119 		psz = PAGEROUND(sz);
1120 		p = map(pool, psz, zero_fill);
1121 		if (p == MAP_FAILED) {
1122 			errno = ENOMEM;
1123 			return NULL;
1124 		}
1125 		if (insert(pool, p, sz, f)) {
1126 			unmap(pool, p, psz, 0, 0);
1127 			errno = ENOMEM;
1128 			return NULL;
1129 		}
1130 		if (mopts.malloc_guard) {
1131 			if (mprotect((char *)p + psz - mopts.malloc_guard,
1132 			    mopts.malloc_guard, PROT_NONE))
1133 				wrterror(pool, "mprotect");
1134 			STATS_ADD(pool->malloc_guarded, mopts.malloc_guard);
1135 		}
1136 
1137 		if (MALLOC_MOVE_COND(sz)) {
1138 			/* fill whole allocation */
1139 			if (pool->malloc_junk == 2)
1140 				memset(p, SOME_JUNK, psz - mopts.malloc_guard);
1141 			/* shift towards the end */
1142 			p = MALLOC_MOVE(p, sz);
1143 			/* fill zeros if needed and overwritten above */
1144 			if (zero_fill && pool->malloc_junk == 2)
1145 				memset(p, 0, sz - mopts.malloc_guard);
1146 		} else {
1147 			if (pool->malloc_junk == 2) {
1148 				if (zero_fill)
1149 					memset((char *)p + sz - mopts.malloc_guard,
1150 					    SOME_JUNK, psz - sz);
1151 				else
1152 					memset(p, SOME_JUNK,
1153 					    psz - mopts.malloc_guard);
1154 			} else if (mopts.chunk_canaries)
1155 				fill_canary(p, sz - mopts.malloc_guard,
1156 				    psz - mopts.malloc_guard);
1157 		}
1158 
1159 	} else {
1160 		/* takes care of SOME_JUNK */
1161 		p = malloc_bytes(pool, sz, f);
1162 		if (zero_fill && p != NULL && sz > 0)
1163 			memset(p, 0, sz);
1164 	}
1165 
1166 	return p;
1167 }
1168 
1169 /*
1170  * Common function for handling recursion.  Only
1171  * print the error message once, to avoid making the problem
1172  * potentially worse.
1173  */
1174 static void
1175 malloc_recurse(struct dir_info *d)
1176 {
1177 	static int noprint;
1178 
1179 	if (noprint == 0) {
1180 		noprint = 1;
1181 		wrterror(d, "recursive call");
1182 	}
1183 	d->active--;
1184 	_MALLOC_UNLOCK(d->mutex);
1185 	errno = EDEADLK;
1186 }
1187 
1188 void
1189 _malloc_init(int from_rthreads)
1190 {
1191 	u_int i, nmutexes;
1192 	struct dir_info *d;
1193 
1194 	_MALLOC_LOCK(1);
1195 	if (!from_rthreads && mopts.malloc_pool[1]) {
1196 		_MALLOC_UNLOCK(1);
1197 		return;
1198 	}
1199 	if (!mopts.malloc_canary)
1200 		omalloc_init();
1201 
1202 	nmutexes = from_rthreads ? mopts.malloc_mutexes : 2;
1203 	if (((uintptr_t)&malloc_readonly & MALLOC_PAGEMASK) == 0)
1204 		mprotect(&malloc_readonly, sizeof(malloc_readonly),
1205 		    PROT_READ | PROT_WRITE);
1206 	for (i = 0; i < nmutexes; i++) {
1207 		if (mopts.malloc_pool[i])
1208 			continue;
1209 		if (i == 0) {
1210 			omalloc_poolinit(&d, MAP_CONCEAL);
1211 			d->malloc_junk = 2;
1212 			d->malloc_cache = 0;
1213 		} else {
1214 			omalloc_poolinit(&d, 0);
1215 			d->malloc_junk = mopts.def_malloc_junk;
1216 			d->malloc_cache = mopts.def_malloc_cache;
1217 		}
1218 		d->mutex = i;
1219 		mopts.malloc_pool[i] = d;
1220 	}
1221 
1222 	if (from_rthreads)
1223 		mopts.malloc_mt = 1;
1224 	else
1225 		mopts.internal_funcs = 1;
1226 
1227 	/*
1228 	 * Options have been set and will never be reset.
1229 	 * Prevent further tampering with them.
1230 	 */
1231 	if (((uintptr_t)&malloc_readonly & MALLOC_PAGEMASK) == 0)
1232 		mprotect(&malloc_readonly, sizeof(malloc_readonly), PROT_READ);
1233 	_MALLOC_UNLOCK(1);
1234 }
1235 DEF_STRONG(_malloc_init);
1236 
1237 #define PROLOGUE(p, fn)			\
1238 	d = (p); 			\
1239 	if (d == NULL) { 		\
1240 		_malloc_init(0);	\
1241 		d = (p);		\
1242 	}				\
1243 	_MALLOC_LOCK(d->mutex);		\
1244 	d->func = fn;			\
1245 	if (d->active++) {		\
1246 		malloc_recurse(d);	\
1247 		return NULL;		\
1248 	}				\
1249 
1250 #define EPILOGUE()				\
1251 	d->active--;				\
1252 	_MALLOC_UNLOCK(d->mutex);		\
1253 	if (r == NULL && mopts.malloc_xmalloc)	\
1254 		wrterror(d, "out of memory");	\
1255 	if (r != NULL)				\
1256 		errno = saved_errno;		\
1257 
1258 void *
1259 malloc(size_t size)
1260 {
1261 	void *r;
1262 	struct dir_info *d;
1263 	int saved_errno = errno;
1264 
1265 	PROLOGUE(getpool(), "malloc")
1266 	r = omalloc(d, size, 0, CALLER);
1267 	EPILOGUE()
1268 	return r;
1269 }
1270 /*DEF_STRONG(malloc);*/
1271 
1272 void *
1273 malloc_conceal(size_t size)
1274 {
1275 	void *r;
1276 	struct dir_info *d;
1277 	int saved_errno = errno;
1278 
1279 	PROLOGUE(mopts.malloc_pool[0], "malloc_conceal")
1280 	r = omalloc(d, size, 0, CALLER);
1281 	EPILOGUE()
1282 	return r;
1283 }
1284 DEF_WEAK(malloc_conceal);
1285 
1286 static void
1287 validate_junk(struct dir_info *pool, void *p)
1288 {
1289 	struct region_info *r;
1290 	size_t byte, sz;
1291 
1292 	if (p == NULL)
1293 		return;
1294 	r = find(pool, p);
1295 	if (r == NULL)
1296 		wrterror(pool, "bogus pointer in validate_junk %p", p);
1297 	REALSIZE(sz, r);
1298 	if (sz > CHUNK_CHECK_LENGTH)
1299 		sz = CHUNK_CHECK_LENGTH;
1300 	for (byte = 0; byte < sz; byte++) {
1301 		if (((unsigned char *)p)[byte] != SOME_FREEJUNK)
1302 			wrterror(pool, "use after free %p", p);
1303 	}
1304 }
1305 
1306 
1307 static struct region_info *
1308 findpool(void *p, struct dir_info *argpool, struct dir_info **foundpool,
1309     char **saved_function)
1310 {
1311 	struct dir_info *pool = argpool;
1312 	struct region_info *r = find(pool, p);
1313 
1314 	STATS_INC(pool->pool_searches);
1315 	if (r == NULL) {
1316 		u_int i, nmutexes;
1317 
1318 		nmutexes = mopts.malloc_mt ? mopts.malloc_mutexes : 2;
1319 		STATS_INC(pool->other_pool);
1320 		for (i = 1; i < nmutexes; i++) {
1321 			u_int j = (argpool->mutex + i) & (nmutexes - 1);
1322 
1323 			pool->active--;
1324 			_MALLOC_UNLOCK(pool->mutex);
1325 			pool = mopts.malloc_pool[j];
1326 			_MALLOC_LOCK(pool->mutex);
1327 			pool->active++;
1328 			r = find(pool, p);
1329 			if (r != NULL) {
1330 				*saved_function = pool->func;
1331 				pool->func = argpool->func;
1332 				break;
1333 			}
1334 		}
1335 		if (r == NULL)
1336 			wrterror(argpool, "bogus pointer (double free?) %p", p);
1337 	}
1338 	*foundpool = pool;
1339 	return r;
1340 }
1341 
1342 static void
1343 ofree(struct dir_info **argpool, void *p, int clear, int check, size_t argsz)
1344 {
1345 	struct region_info *r;
1346 	struct dir_info *pool;
1347 	char *saved_function;
1348 	size_t sz;
1349 
1350 	r = findpool(p, *argpool, &pool, &saved_function);
1351 
1352 	REALSIZE(sz, r);
1353 	if (pool->mmap_flag) {
1354 		clear = 1;
1355 		if (!check)
1356 			argsz = sz;
1357 	}
1358 	if (check) {
1359 		if (sz <= MALLOC_MAXCHUNK) {
1360 			if (mopts.chunk_canaries && sz > 0) {
1361 				struct chunk_info *info =
1362 				    (struct chunk_info *)r->size;
1363 				uint32_t chunknum =
1364 				    find_chunknum(pool, info, p, 0);
1365 
1366 				if (info->bits[info->offset + chunknum] < argsz)
1367 					wrterror(pool, "recorded size %hu"
1368 					    " < %zu",
1369 					    info->bits[info->offset + chunknum],
1370 					    argsz);
1371 			} else {
1372 				if (sz < argsz)
1373 					wrterror(pool, "chunk size %zu < %zu",
1374 					    sz, argsz);
1375 			}
1376 		} else if (sz - mopts.malloc_guard < argsz) {
1377 			wrterror(pool, "recorded size %zu < %zu",
1378 			    sz - mopts.malloc_guard, argsz);
1379 		}
1380 	}
1381 	if (sz > MALLOC_MAXCHUNK) {
1382 		if (!MALLOC_MOVE_COND(sz)) {
1383 			if (r->p != p)
1384 				wrterror(pool, "bogus pointer %p", p);
1385 			if (mopts.chunk_canaries)
1386 				validate_canary(pool, p,
1387 				    sz - mopts.malloc_guard,
1388 				    PAGEROUND(sz - mopts.malloc_guard));
1389 		} else {
1390 			/* shifted towards the end */
1391 			if (p != MALLOC_MOVE(r->p, sz))
1392 				wrterror(pool, "bogus moved pointer %p", p);
1393 			p = r->p;
1394 		}
1395 		if (mopts.malloc_guard) {
1396 			if (sz < mopts.malloc_guard)
1397 				wrterror(pool, "guard size");
1398 			if (!mopts.malloc_freeunmap) {
1399 				if (mprotect((char *)p + PAGEROUND(sz) -
1400 				    mopts.malloc_guard, mopts.malloc_guard,
1401 				    PROT_READ | PROT_WRITE))
1402 					wrterror(pool, "mprotect");
1403 			}
1404 			STATS_SUB(pool->malloc_guarded, mopts.malloc_guard);
1405 		}
1406 		unmap(pool, p, PAGEROUND(sz), clear ? argsz : 0,
1407 		    pool->malloc_junk);
1408 		delete(pool, r);
1409 	} else {
1410 		/* Validate and optionally canary check */
1411 		struct chunk_info *info = (struct chunk_info *)r->size;
1412 		find_chunknum(pool, info, p, mopts.chunk_canaries);
1413 		if (!clear) {
1414 			void *tmp;
1415 			int i;
1416 
1417 			if (mopts.malloc_freecheck) {
1418 				for (i = 0; i <= MALLOC_DELAYED_CHUNK_MASK; i++)
1419 					if (p == pool->delayed_chunks[i])
1420 						wrterror(pool,
1421 						    "double free %p", p);
1422 			}
1423 			if (pool->malloc_junk && sz > 0)
1424 				memset(p, SOME_FREEJUNK, sz);
1425 			i = getrbyte(pool) & MALLOC_DELAYED_CHUNK_MASK;
1426 			tmp = p;
1427 			p = pool->delayed_chunks[i];
1428 			if (tmp == p)
1429 				wrterror(pool, "double free %p", tmp);
1430 			pool->delayed_chunks[i] = tmp;
1431 			if (pool->malloc_junk)
1432 				validate_junk(pool, p);
1433 		} else if (argsz > 0)
1434 			memset(p, 0, argsz);
1435 		if (p != NULL) {
1436 			r = find(pool, p);
1437 			if (r == NULL)
1438 				wrterror(pool,
1439 				    "bogus pointer (double free?) %p", p);
1440 			free_bytes(pool, r, p);
1441 		}
1442 	}
1443 
1444 	if (*argpool != pool) {
1445 		pool->func = saved_function;
1446 		*argpool = pool;
1447 	}
1448 }
1449 
1450 void
1451 free(void *ptr)
1452 {
1453 	struct dir_info *d;
1454 	int saved_errno = errno;
1455 
1456 	/* This is legal. */
1457 	if (ptr == NULL)
1458 		return;
1459 
1460 	d = getpool();
1461 	if (d == NULL)
1462 		wrterror(d, "free() called before allocation");
1463 	_MALLOC_LOCK(d->mutex);
1464 	d->func = "free";
1465 	if (d->active++) {
1466 		malloc_recurse(d);
1467 		return;
1468 	}
1469 	ofree(&d, ptr, 0, 0, 0);
1470 	d->active--;
1471 	_MALLOC_UNLOCK(d->mutex);
1472 	errno = saved_errno;
1473 }
1474 /*DEF_STRONG(free);*/
1475 
1476 static void
1477 freezero_p(void *ptr, size_t sz)
1478 {
1479 	explicit_bzero(ptr, sz);
1480 	free(ptr);
1481 }
1482 
1483 void
1484 freezero(void *ptr, size_t sz)
1485 {
1486 	struct dir_info *d;
1487 	int saved_errno = errno;
1488 
1489 	/* This is legal. */
1490 	if (ptr == NULL)
1491 		return;
1492 
1493 	if (!mopts.internal_funcs) {
1494 		freezero_p(ptr, sz);
1495 		return;
1496 	}
1497 
1498 	d = getpool();
1499 	if (d == NULL)
1500 		wrterror(d, "freezero() called before allocation");
1501 	_MALLOC_LOCK(d->mutex);
1502 	d->func = "freezero";
1503 	if (d->active++) {
1504 		malloc_recurse(d);
1505 		return;
1506 	}
1507 	ofree(&d, ptr, 1, 1, sz);
1508 	d->active--;
1509 	_MALLOC_UNLOCK(d->mutex);
1510 	errno = saved_errno;
1511 }
1512 DEF_WEAK(freezero);
1513 
1514 static void *
1515 orealloc(struct dir_info **argpool, void *p, size_t newsz, void *f)
1516 {
1517 	struct region_info *r;
1518 	struct dir_info *pool;
1519 	char *saved_function;
1520 	struct chunk_info *info;
1521 	size_t oldsz, goldsz, gnewsz;
1522 	void *q, *ret;
1523 	uint32_t chunknum;
1524 	int forced;
1525 
1526 	if (p == NULL)
1527 		return omalloc(*argpool, newsz, 0, f);
1528 
1529 	if (newsz >= SIZE_MAX - mopts.malloc_guard - MALLOC_PAGESIZE) {
1530 		errno = ENOMEM;
1531 		return  NULL;
1532 	}
1533 
1534 	r = findpool(p, *argpool, &pool, &saved_function);
1535 
1536 	REALSIZE(oldsz, r);
1537 	if (mopts.chunk_canaries && oldsz <= MALLOC_MAXCHUNK) {
1538 		info = (struct chunk_info *)r->size;
1539 		chunknum = find_chunknum(pool, info, p, 0);
1540 	}
1541 
1542 	goldsz = oldsz;
1543 	if (oldsz > MALLOC_MAXCHUNK) {
1544 		if (oldsz < mopts.malloc_guard)
1545 			wrterror(pool, "guard size");
1546 		oldsz -= mopts.malloc_guard;
1547 	}
1548 
1549 	gnewsz = newsz;
1550 	if (gnewsz > MALLOC_MAXCHUNK)
1551 		gnewsz += mopts.malloc_guard;
1552 
1553 	forced = mopts.malloc_realloc || pool->mmap_flag;
1554 	if (newsz > MALLOC_MAXCHUNK && oldsz > MALLOC_MAXCHUNK && !forced) {
1555 		/* First case: from n pages sized allocation to m pages sized
1556 		   allocation, m > n */
1557 		size_t roldsz = PAGEROUND(goldsz);
1558 		size_t rnewsz = PAGEROUND(gnewsz);
1559 
1560 		if (rnewsz < roldsz && rnewsz > roldsz / 2 &&
1561 		    roldsz - rnewsz < pool->malloc_cache * MALLOC_PAGESIZE &&
1562 		    !mopts.malloc_guard) {
1563 
1564 			ret = p;
1565 			goto done;
1566 		}
1567 
1568 		if (rnewsz > roldsz) {
1569 			/* try to extend existing region */
1570 			if (!mopts.malloc_guard) {
1571 				void *hint = (char *)r->p + roldsz;
1572 				size_t needed = rnewsz - roldsz;
1573 
1574 				STATS_INC(pool->cheap_realloc_tries);
1575 				q = MQUERY(hint, needed, pool->mmap_flag);
1576 				if (q == hint)
1577 					q = MMAPA(hint, needed, pool->mmap_flag);
1578 				else
1579 					q = MAP_FAILED;
1580 				if (q == hint) {
1581 					STATS_ADD(pool->malloc_used, needed);
1582 					if (pool->malloc_junk == 2)
1583 						memset(q, SOME_JUNK, needed);
1584 					r->size = gnewsz;
1585 					if (r->p != p) {
1586 						/* old pointer is moved */
1587 						memmove(r->p, p, oldsz);
1588 						p = r->p;
1589 					}
1590 					if (mopts.chunk_canaries)
1591 						fill_canary(p, newsz,
1592 						    PAGEROUND(newsz));
1593 					STATS_SETF(r, f);
1594 					STATS_INC(pool->cheap_reallocs);
1595 					ret = p;
1596 					goto done;
1597 				} else if (q != MAP_FAILED) {
1598 					if (munmap(q, needed))
1599 						wrterror(pool, "munmap %p", q);
1600 				}
1601 			}
1602 		} else if (rnewsz < roldsz) {
1603 			/* shrink number of pages */
1604 			if (mopts.malloc_guard) {
1605 				if (mprotect((char *)r->p + rnewsz -
1606 				    mopts.malloc_guard, mopts.malloc_guard,
1607 				    PROT_NONE))
1608 					wrterror(pool, "mprotect");
1609 			}
1610 			if (munmap((char *)r->p + rnewsz, roldsz - rnewsz))
1611 				wrterror(pool, "munmap %p", (char *)r->p + rnewsz);
1612 			r->size = gnewsz;
1613 			if (MALLOC_MOVE_COND(gnewsz)) {
1614 				void *pp = MALLOC_MOVE(r->p, gnewsz);
1615 				memmove(pp, p, newsz);
1616 				p = pp;
1617 			} else if (mopts.chunk_canaries)
1618 				fill_canary(p, newsz, PAGEROUND(newsz));
1619 			STATS_SETF(r, f);
1620 			ret = p;
1621 			goto done;
1622 		} else {
1623 			/* number of pages remains the same */
1624 			void *pp = r->p;
1625 
1626 			r->size = gnewsz;
1627 			if (MALLOC_MOVE_COND(gnewsz))
1628 				pp = MALLOC_MOVE(r->p, gnewsz);
1629 			if (p != pp) {
1630 				memmove(pp, p, oldsz < newsz ? oldsz : newsz);
1631 				p = pp;
1632 			}
1633 			if (p == r->p) {
1634 				if (newsz > oldsz && pool->malloc_junk == 2)
1635 					memset((char *)p + newsz, SOME_JUNK,
1636 					    rnewsz - mopts.malloc_guard -
1637 					    newsz);
1638 				if (mopts.chunk_canaries)
1639 					fill_canary(p, newsz, PAGEROUND(newsz));
1640 			}
1641 			STATS_SETF(r, f);
1642 			ret = p;
1643 			goto done;
1644 		}
1645 	}
1646 	if (oldsz <= MALLOC_MAXCHUNK && oldsz > 0 &&
1647 	    newsz <= MALLOC_MAXCHUNK && newsz > 0 &&
1648 	    1 << find_chunksize(newsz) == oldsz && !forced) {
1649 		/* do not reallocate if new size fits good in existing chunk */
1650 		if (pool->malloc_junk == 2)
1651 			memset((char *)p + newsz, SOME_JUNK, oldsz - newsz);
1652 		if (mopts.chunk_canaries) {
1653 			info->bits[info->offset + chunknum] = newsz;
1654 			fill_canary(p, newsz, info->size);
1655 		}
1656 		STATS_SETF(r, f);
1657 		ret = p;
1658 	} else if (newsz != oldsz || forced) {
1659 		/* create new allocation */
1660 		q = omalloc(pool, newsz, 0, f);
1661 		if (q == NULL) {
1662 			ret = NULL;
1663 			goto done;
1664 		}
1665 		if (newsz != 0 && oldsz != 0)
1666 			memcpy(q, p, oldsz < newsz ? oldsz : newsz);
1667 		ofree(&pool, p, 0, 0, 0);
1668 		ret = q;
1669 	} else {
1670 		/* oldsz == newsz */
1671 		if (newsz != 0)
1672 			wrterror(pool, "realloc internal inconsistency");
1673 		STATS_SETF(r, f);
1674 		ret = p;
1675 	}
1676 done:
1677 	if (*argpool != pool) {
1678 		pool->func = saved_function;
1679 		*argpool = pool;
1680 	}
1681 	return ret;
1682 }
1683 
1684 void *
1685 realloc(void *ptr, size_t size)
1686 {
1687 	struct dir_info *d;
1688 	void *r;
1689 	int saved_errno = errno;
1690 
1691 	PROLOGUE(getpool(), "realloc")
1692 	r = orealloc(&d, ptr, size, CALLER);
1693 	EPILOGUE()
1694 	return r;
1695 }
1696 /*DEF_STRONG(realloc);*/
1697 
1698 /*
1699  * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
1700  * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
1701  */
1702 #define MUL_NO_OVERFLOW	(1UL << (sizeof(size_t) * 4))
1703 
1704 void *
1705 calloc(size_t nmemb, size_t size)
1706 {
1707 	struct dir_info *d;
1708 	void *r;
1709 	int saved_errno = errno;
1710 
1711 	PROLOGUE(getpool(), "calloc")
1712 	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
1713 	    nmemb > 0 && SIZE_MAX / nmemb < size) {
1714 		d->active--;
1715 		_MALLOC_UNLOCK(d->mutex);
1716 		if (mopts.malloc_xmalloc)
1717 			wrterror(d, "out of memory");
1718 		errno = ENOMEM;
1719 		return NULL;
1720 	}
1721 
1722 	size *= nmemb;
1723 	r = omalloc(d, size, 1, CALLER);
1724 	EPILOGUE()
1725 	return r;
1726 }
1727 /*DEF_STRONG(calloc);*/
1728 
1729 void *
1730 calloc_conceal(size_t nmemb, size_t size)
1731 {
1732 	struct dir_info *d;
1733 	void *r;
1734 	int saved_errno = errno;
1735 
1736 	PROLOGUE(mopts.malloc_pool[0], "calloc_conceal")
1737 	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
1738 	    nmemb > 0 && SIZE_MAX / nmemb < size) {
1739 		d->active--;
1740 		_MALLOC_UNLOCK(d->mutex);
1741 		if (mopts.malloc_xmalloc)
1742 			wrterror(d, "out of memory");
1743 		errno = ENOMEM;
1744 		return NULL;
1745 	}
1746 
1747 	size *= nmemb;
1748 	r = omalloc(d, size, 1, CALLER);
1749 	EPILOGUE()
1750 	return r;
1751 }
1752 DEF_WEAK(calloc_conceal);
1753 
1754 static void *
1755 orecallocarray(struct dir_info **argpool, void *p, size_t oldsize,
1756     size_t newsize, void *f)
1757 {
1758 	struct region_info *r;
1759 	struct dir_info *pool;
1760 	char *saved_function;
1761 	void *newptr;
1762 	size_t sz;
1763 
1764 	if (p == NULL)
1765 		return omalloc(*argpool, newsize, 1, f);
1766 
1767 	if (oldsize == newsize)
1768 		return p;
1769 
1770 	r = findpool(p, *argpool, &pool, &saved_function);
1771 
1772 	REALSIZE(sz, r);
1773 	if (sz <= MALLOC_MAXCHUNK) {
1774 		if (mopts.chunk_canaries && sz > 0) {
1775 			struct chunk_info *info = (struct chunk_info *)r->size;
1776 			uint32_t chunknum = find_chunknum(pool, info, p, 0);
1777 
1778 			if (info->bits[info->offset + chunknum] != oldsize)
1779 				wrterror(pool, "recorded old size %hu != %zu",
1780 				    info->bits[info->offset + chunknum],
1781 				    oldsize);
1782 		}
1783 	} else if (oldsize < (sz - mopts.malloc_guard) / 2)
1784 		wrterror(pool, "recorded old size %zu != %zu",
1785 		    sz - mopts.malloc_guard, oldsize);
1786 
1787 	newptr = omalloc(pool, newsize, 0, f);
1788 	if (newptr == NULL)
1789 		goto done;
1790 
1791 	if (newsize > oldsize) {
1792 		memcpy(newptr, p, oldsize);
1793 		memset((char *)newptr + oldsize, 0, newsize - oldsize);
1794 	} else
1795 		memcpy(newptr, p, newsize);
1796 
1797 	ofree(&pool, p, 1, 0, oldsize);
1798 
1799 done:
1800 	if (*argpool != pool) {
1801 		pool->func = saved_function;
1802 		*argpool = pool;
1803 	}
1804 
1805 	return newptr;
1806 }
1807 
1808 static void *
1809 recallocarray_p(void *ptr, size_t oldnmemb, size_t newnmemb, size_t size)
1810 {
1811 	size_t oldsize, newsize;
1812 	void *newptr;
1813 
1814 	if (ptr == NULL)
1815 		return calloc(newnmemb, size);
1816 
1817 	if ((newnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
1818 	    newnmemb > 0 && SIZE_MAX / newnmemb < size) {
1819 		errno = ENOMEM;
1820 		return NULL;
1821 	}
1822 	newsize = newnmemb * size;
1823 
1824 	if ((oldnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
1825 	    oldnmemb > 0 && SIZE_MAX / oldnmemb < size) {
1826 		errno = EINVAL;
1827 		return NULL;
1828 	}
1829 	oldsize = oldnmemb * size;
1830 
1831 	/*
1832 	 * Don't bother too much if we're shrinking just a bit,
1833 	 * we do not shrink for series of small steps, oh well.
1834 	 */
1835 	if (newsize <= oldsize) {
1836 		size_t d = oldsize - newsize;
1837 
1838 		if (d < oldsize / 2 && d < MALLOC_PAGESIZE) {
1839 			memset((char *)ptr + newsize, 0, d);
1840 			return ptr;
1841 		}
1842 	}
1843 
1844 	newptr = malloc(newsize);
1845 	if (newptr == NULL)
1846 		return NULL;
1847 
1848 	if (newsize > oldsize) {
1849 		memcpy(newptr, ptr, oldsize);
1850 		memset((char *)newptr + oldsize, 0, newsize - oldsize);
1851 	} else
1852 		memcpy(newptr, ptr, newsize);
1853 
1854 	explicit_bzero(ptr, oldsize);
1855 	free(ptr);
1856 
1857 	return newptr;
1858 }
1859 
1860 void *
1861 recallocarray(void *ptr, size_t oldnmemb, size_t newnmemb, size_t size)
1862 {
1863 	struct dir_info *d;
1864 	size_t oldsize = 0, newsize;
1865 	void *r;
1866 	int saved_errno = errno;
1867 
1868 	if (!mopts.internal_funcs)
1869 		return recallocarray_p(ptr, oldnmemb, newnmemb, size);
1870 
1871 	PROLOGUE(getpool(), "recallocarray")
1872 
1873 	if ((newnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
1874 	    newnmemb > 0 && SIZE_MAX / newnmemb < size) {
1875 		d->active--;
1876 		_MALLOC_UNLOCK(d->mutex);
1877 		if (mopts.malloc_xmalloc)
1878 			wrterror(d, "out of memory");
1879 		errno = ENOMEM;
1880 		return NULL;
1881 	}
1882 	newsize = newnmemb * size;
1883 
1884 	if (ptr != NULL) {
1885 		if ((oldnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
1886 		    oldnmemb > 0 && SIZE_MAX / oldnmemb < size) {
1887 			d->active--;
1888 			_MALLOC_UNLOCK(d->mutex);
1889 			errno = EINVAL;
1890 			return NULL;
1891 		}
1892 		oldsize = oldnmemb * size;
1893 	}
1894 
1895 	r = orecallocarray(&d, ptr, oldsize, newsize, CALLER);
1896 	EPILOGUE()
1897 	return r;
1898 }
1899 DEF_WEAK(recallocarray);
1900 
1901 static void *
1902 mapalign(struct dir_info *d, size_t alignment, size_t sz, int zero_fill)
1903 {
1904 	char *p, *q;
1905 
1906 	if (alignment < MALLOC_PAGESIZE || ((alignment - 1) & alignment) != 0)
1907 		wrterror(d, "mapalign bad alignment");
1908 	if (sz != PAGEROUND(sz))
1909 		wrterror(d, "mapalign round");
1910 
1911 	/* Allocate sz + alignment bytes of memory, which must include a
1912 	 * subrange of size bytes that is properly aligned.  Unmap the
1913 	 * other bytes, and then return that subrange.
1914 	 */
1915 
1916 	/* We need sz + alignment to fit into a size_t. */
1917 	if (alignment > SIZE_MAX - sz)
1918 		return MAP_FAILED;
1919 
1920 	p = map(d, sz + alignment, zero_fill);
1921 	if (p == MAP_FAILED)
1922 		return MAP_FAILED;
1923 	q = (char *)(((uintptr_t)p + alignment - 1) & ~(alignment - 1));
1924 	if (q != p) {
1925 		if (munmap(p, q - p))
1926 			wrterror(d, "munmap %p", p);
1927 	}
1928 	if (munmap(q + sz, alignment - (q - p)))
1929 		wrterror(d, "munmap %p", q + sz);
1930 	STATS_SUB(d->malloc_used, alignment);
1931 
1932 	return q;
1933 }
1934 
1935 static void *
1936 omemalign(struct dir_info *pool, size_t alignment, size_t sz, int zero_fill,
1937     void *f)
1938 {
1939 	size_t psz;
1940 	void *p;
1941 
1942 	/* If between half a page and a page, avoid MALLOC_MOVE. */
1943 	if (sz > MALLOC_MAXCHUNK && sz < MALLOC_PAGESIZE)
1944 		sz = MALLOC_PAGESIZE;
1945 	if (alignment <= MALLOC_PAGESIZE) {
1946 		/*
1947 		 * max(size, alignment) is enough to assure the requested
1948 		 * alignment, since the allocator always allocates
1949 		 * power-of-two blocks.
1950 		 */
1951 		if (sz < alignment)
1952 			sz = alignment;
1953 		return omalloc(pool, sz, zero_fill, f);
1954 	}
1955 
1956 	if (sz >= SIZE_MAX - mopts.malloc_guard - MALLOC_PAGESIZE) {
1957 		errno = ENOMEM;
1958 		return NULL;
1959 	}
1960 
1961 	sz += mopts.malloc_guard;
1962 	psz = PAGEROUND(sz);
1963 
1964 	p = mapalign(pool, alignment, psz, zero_fill);
1965 	if (p == MAP_FAILED) {
1966 		errno = ENOMEM;
1967 		return NULL;
1968 	}
1969 
1970 	if (insert(pool, p, sz, f)) {
1971 		unmap(pool, p, psz, 0, 0);
1972 		errno = ENOMEM;
1973 		return NULL;
1974 	}
1975 
1976 	if (mopts.malloc_guard) {
1977 		if (mprotect((char *)p + psz - mopts.malloc_guard,
1978 		    mopts.malloc_guard, PROT_NONE))
1979 			wrterror(pool, "mprotect");
1980 		STATS_ADD(pool->malloc_guarded, mopts.malloc_guard);
1981 	}
1982 
1983 	if (pool->malloc_junk == 2) {
1984 		if (zero_fill)
1985 			memset((char *)p + sz - mopts.malloc_guard,
1986 			    SOME_JUNK, psz - sz);
1987 		else
1988 			memset(p, SOME_JUNK, psz - mopts.malloc_guard);
1989 	} else if (mopts.chunk_canaries)
1990 		fill_canary(p, sz - mopts.malloc_guard,
1991 		    psz - mopts.malloc_guard);
1992 
1993 	return p;
1994 }
1995 
1996 int
1997 posix_memalign(void **memptr, size_t alignment, size_t size)
1998 {
1999 	struct dir_info *d;
2000 	int res, saved_errno = errno;
2001 	void *r;
2002 
2003 	/* Make sure that alignment is a large enough power of 2. */
2004 	if (((alignment - 1) & alignment) != 0 || alignment < sizeof(void *))
2005 		return EINVAL;
2006 
2007 	d = getpool();
2008 	if (d == NULL) {
2009 		_malloc_init(0);
2010 		d = getpool();
2011 	}
2012 	_MALLOC_LOCK(d->mutex);
2013 	d->func = "posix_memalign";
2014 	if (d->active++) {
2015 		malloc_recurse(d);
2016 		goto err;
2017 	}
2018 	r = omemalign(d, alignment, size, 0, CALLER);
2019 	d->active--;
2020 	_MALLOC_UNLOCK(d->mutex);
2021 	if (r == NULL) {
2022 		if (mopts.malloc_xmalloc)
2023 			wrterror(d, "out of memory");
2024 		goto err;
2025 	}
2026 	errno = saved_errno;
2027 	*memptr = r;
2028 	return 0;
2029 
2030 err:
2031 	res = errno;
2032 	errno = saved_errno;
2033 	return res;
2034 }
2035 /*DEF_STRONG(posix_memalign);*/
2036 
2037 void *
2038 aligned_alloc(size_t alignment, size_t size)
2039 {
2040 	struct dir_info *d;
2041 	int saved_errno = errno;
2042 	void *r;
2043 
2044 	/* Make sure that alignment is a positive power of 2. */
2045 	if (((alignment - 1) & alignment) != 0 || alignment == 0) {
2046 		errno = EINVAL;
2047 		return NULL;
2048 	};
2049 	/* Per spec, size should be a multiple of alignment */
2050 	if ((size & (alignment - 1)) != 0) {
2051 		errno = EINVAL;
2052 		return NULL;
2053 	}
2054 
2055 	PROLOGUE(getpool(), "aligned_alloc")
2056 	r = omemalign(d, alignment, size, 0, CALLER);
2057 	EPILOGUE()
2058 	return r;
2059 }
2060 /*DEF_STRONG(aligned_alloc);*/
2061 
2062 #ifdef MALLOC_STATS
2063 
2064 struct malloc_leak {
2065 	void *f;
2066 	size_t total_size;
2067 	int count;
2068 };
2069 
2070 struct leaknode {
2071 	RBT_ENTRY(leaknode) entry;
2072 	struct malloc_leak d;
2073 };
2074 
2075 static inline int
2076 leakcmp(const struct leaknode *e1, const struct leaknode *e2)
2077 {
2078 	return e1->d.f < e2->d.f ? -1 : e1->d.f > e2->d.f;
2079 }
2080 
2081 static RBT_HEAD(leaktree, leaknode) leakhead;
2082 RBT_PROTOTYPE(leaktree, leaknode, entry, leakcmp);
2083 RBT_GENERATE(leaktree, leaknode, entry, leakcmp);
2084 
2085 static void
2086 putleakinfo(void *f, size_t sz, int cnt)
2087 {
2088 	struct leaknode key, *p;
2089 	static struct leaknode *page;
2090 	static int used;
2091 
2092 	if (cnt == 0 || page == MAP_FAILED)
2093 		return;
2094 
2095 	key.d.f = f;
2096 	p = RBT_FIND(leaktree, &leakhead, &key);
2097 	if (p == NULL) {
2098 		if (page == NULL ||
2099 		    used >= MALLOC_PAGESIZE / sizeof(struct leaknode)) {
2100 			page = MMAP(MALLOC_PAGESIZE, 0);
2101 			if (page == MAP_FAILED)
2102 				return;
2103 			used = 0;
2104 		}
2105 		p = &page[used++];
2106 		p->d.f = f;
2107 		p->d.total_size = sz * cnt;
2108 		p->d.count = cnt;
2109 		RBT_INSERT(leaktree, &leakhead, p);
2110 	} else {
2111 		p->d.total_size += sz * cnt;
2112 		p->d.count += cnt;
2113 	}
2114 }
2115 
2116 static struct malloc_leak *malloc_leaks;
2117 
2118 static void
2119 dump_leaks(int fd)
2120 {
2121 	struct leaknode *p;
2122 	int i = 0;
2123 
2124 	dprintf(fd, "Leak report\n");
2125 	dprintf(fd, "                 f     sum      #    avg\n");
2126 	/* XXX only one page of summary */
2127 	if (malloc_leaks == NULL)
2128 		malloc_leaks = MMAP(MALLOC_PAGESIZE, 0);
2129 	if (malloc_leaks != MAP_FAILED)
2130 		memset(malloc_leaks, 0, MALLOC_PAGESIZE);
2131 	RBT_FOREACH(p, leaktree, &leakhead) {
2132 		dprintf(fd, "%18p %7zu %6u %6zu\n", p->d.f,
2133 		    p->d.total_size, p->d.count, p->d.total_size / p->d.count);
2134 		if (malloc_leaks == MAP_FAILED ||
2135 		    i >= MALLOC_PAGESIZE / sizeof(struct malloc_leak))
2136 			continue;
2137 		malloc_leaks[i].f = p->d.f;
2138 		malloc_leaks[i].total_size = p->d.total_size;
2139 		malloc_leaks[i].count = p->d.count;
2140 		i++;
2141 	}
2142 }
2143 
2144 static void
2145 dump_chunk(int fd, struct chunk_info *p, void *f, int fromfreelist)
2146 {
2147 	while (p != NULL) {
2148 		dprintf(fd, "chunk %18p %18p %4d %d/%d\n",
2149 		    p->page, ((p->bits[0] & 1) ? NULL : f),
2150 		    p->size, p->free, p->total);
2151 		if (!fromfreelist) {
2152 			if (p->bits[0] & 1)
2153 				putleakinfo(NULL, p->size, p->total - p->free);
2154 			else {
2155 				putleakinfo(f, p->size, 1);
2156 				putleakinfo(NULL, p->size,
2157 				    p->total - p->free - 1);
2158 			}
2159 			break;
2160 		}
2161 		p = LIST_NEXT(p, entries);
2162 		if (p != NULL)
2163 			dprintf(fd, "        ");
2164 	}
2165 }
2166 
2167 static void
2168 dump_free_chunk_info(int fd, struct dir_info *d)
2169 {
2170 	int i, j, count;
2171 	struct chunk_info *p;
2172 
2173 	dprintf(fd, "Free chunk structs:\n");
2174 	for (i = 0; i <= MALLOC_MAXSHIFT; i++) {
2175 		count = 0;
2176 		LIST_FOREACH(p, &d->chunk_info_list[i], entries)
2177 			count++;
2178 		for (j = 0; j < MALLOC_CHUNK_LISTS; j++) {
2179 			p = LIST_FIRST(&d->chunk_dir[i][j]);
2180 			if (p == NULL && count == 0)
2181 				continue;
2182 			dprintf(fd, "%2d) %3d ", i, count);
2183 			if (p != NULL)
2184 				dump_chunk(fd, p, NULL, 1);
2185 			else
2186 				dprintf(fd, "\n");
2187 		}
2188 	}
2189 
2190 }
2191 
2192 static void
2193 dump_free_page_info(int fd, struct dir_info *d)
2194 {
2195 	int i;
2196 
2197 	dprintf(fd, "Free pages cached: %zu\n", d->free_regions_size);
2198 	for (i = 0; i < d->malloc_cache; i++) {
2199 		if (d->free_regions[i].p != NULL) {
2200 			dprintf(fd, "%2d) ", i);
2201 			dprintf(fd, "free at %p: %zu\n",
2202 			    d->free_regions[i].p, d->free_regions[i].size);
2203 		}
2204 	}
2205 }
2206 
2207 static void
2208 malloc_dump1(int fd, int poolno, struct dir_info *d)
2209 {
2210 	size_t i, realsize;
2211 
2212 	dprintf(fd, "Malloc dir of %s pool %d at %p\n", __progname, poolno, d);
2213 	if (d == NULL)
2214 		return;
2215 	dprintf(fd, "J=%d cache=%u Fl=%x\n",
2216 	    d->malloc_junk, d->malloc_cache, d->mmap_flag);
2217 	dprintf(fd, "Region slots free %zu/%zu\n",
2218 		d->regions_free, d->regions_total);
2219 	dprintf(fd, "Finds %zu/%zu\n", d->finds, d->find_collisions);
2220 	dprintf(fd, "Inserts %zu/%zu\n", d->inserts, d->insert_collisions);
2221 	dprintf(fd, "Deletes %zu/%zu\n", d->deletes, d->delete_moves);
2222 	dprintf(fd, "Cheap reallocs %zu/%zu\n",
2223 	    d->cheap_reallocs, d->cheap_realloc_tries);
2224 	dprintf(fd, "Other pool searches %zu/%zu\n",
2225 	    d->other_pool, d->pool_searches);
2226 	dprintf(fd, "In use %zu\n", d->malloc_used);
2227 	dprintf(fd, "Guarded %zu\n", d->malloc_guarded);
2228 	dump_free_chunk_info(fd, d);
2229 	dump_free_page_info(fd, d);
2230 	dprintf(fd,
2231 	    "slot)  hash d  type               page                  f size [free/n]\n");
2232 	for (i = 0; i < d->regions_total; i++) {
2233 		if (d->r[i].p != NULL) {
2234 			size_t h = hash(d->r[i].p) &
2235 			    (d->regions_total - 1);
2236 			dprintf(fd, "%4zx) #%4zx %zd ",
2237 			    i, h, h - i);
2238 			REALSIZE(realsize, &d->r[i]);
2239 			if (realsize > MALLOC_MAXCHUNK) {
2240 				putleakinfo(d->r[i].f, realsize, 1);
2241 				dprintf(fd,
2242 				    "pages %18p %18p %zu\n", d->r[i].p,
2243 				    d->r[i].f, realsize);
2244 			} else
2245 				dump_chunk(fd,
2246 				    (struct chunk_info *)d->r[i].size,
2247 				    d->r[i].f, 0);
2248 		}
2249 	}
2250 	dump_leaks(fd);
2251 	dprintf(fd, "\n");
2252 }
2253 
2254 void
2255 malloc_dump(int fd, int poolno, struct dir_info *pool)
2256 {
2257 	int i;
2258 	void *p;
2259 	struct region_info *r;
2260 	int saved_errno = errno;
2261 
2262 	if (pool == NULL)
2263 		return;
2264 	for (i = 0; i < MALLOC_DELAYED_CHUNK_MASK + 1; i++) {
2265 		p = pool->delayed_chunks[i];
2266 		if (p == NULL)
2267 			continue;
2268 		r = find(pool, p);
2269 		if (r == NULL)
2270 			wrterror(pool, "bogus pointer in malloc_dump %p", p);
2271 		free_bytes(pool, r, p);
2272 		pool->delayed_chunks[i] = NULL;
2273 	}
2274 	/* XXX leak when run multiple times */
2275 	RBT_INIT(leaktree, &leakhead);
2276 	malloc_dump1(fd, poolno, pool);
2277 	errno = saved_errno;
2278 }
2279 DEF_WEAK(malloc_dump);
2280 
2281 void
2282 malloc_gdump(int fd)
2283 {
2284 	int i;
2285 	int saved_errno = errno;
2286 
2287 	for (i = 0; i < mopts.malloc_mutexes; i++)
2288 		malloc_dump(fd, i, mopts.malloc_pool[i]);
2289 
2290 	errno = saved_errno;
2291 }
2292 DEF_WEAK(malloc_gdump);
2293 
2294 static void
2295 malloc_exit(void)
2296 {
2297 	int save_errno = errno, fd, i;
2298 
2299 	fd = open("malloc.out", O_RDWR|O_APPEND);
2300 	if (fd != -1) {
2301 		dprintf(fd, "******** Start dump %s *******\n", __progname);
2302 		dprintf(fd,
2303 		    "MT=%d M=%u I=%d F=%d U=%d J=%d R=%d X=%d C=%d cache=%u G=%zu\n",
2304 		    mopts.malloc_mt, mopts.malloc_mutexes,
2305 		    mopts.internal_funcs, mopts.malloc_freecheck,
2306 		    mopts.malloc_freeunmap, mopts.def_malloc_junk,
2307 		    mopts.malloc_realloc, mopts.malloc_xmalloc,
2308 		    mopts.chunk_canaries, mopts.def_malloc_cache,
2309 		    mopts.malloc_guard);
2310 
2311 		for (i = 0; i < mopts.malloc_mutexes; i++)
2312 			malloc_dump(fd, i, mopts.malloc_pool[i]);
2313 		dprintf(fd, "******** End dump %s *******\n", __progname);
2314 		close(fd);
2315 	} else
2316 		dprintf(STDERR_FILENO,
2317 		    "malloc() warning: Couldn't dump stats\n");
2318 	errno = save_errno;
2319 }
2320 
2321 #endif /* MALLOC_STATS */
2322