1 /* $OpenBSD: malloc.c,v 1.264 2020/10/06 06:31:14 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 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 } 472 473 static void 474 omalloc_poolinit(struct dir_info **dp, int mmap_flag) 475 { 476 char *p; 477 size_t d_avail, regioninfo_size; 478 struct dir_info *d; 479 int i, j; 480 481 /* 482 * Allocate dir_info with a guard page on either side. Also 483 * randomise offset inside the page at which the dir_info 484 * lies (subject to alignment by 1 << MALLOC_MINSHIFT) 485 */ 486 if ((p = MMAPNONE(DIR_INFO_RSZ + (MALLOC_PAGESIZE * 2), mmap_flag)) == 487 MAP_FAILED) 488 wrterror(NULL, "malloc init mmap failed"); 489 mprotect(p + MALLOC_PAGESIZE, DIR_INFO_RSZ, PROT_READ | PROT_WRITE); 490 d_avail = (DIR_INFO_RSZ - sizeof(*d)) >> MALLOC_MINSHIFT; 491 d = (struct dir_info *)(p + MALLOC_PAGESIZE + 492 (arc4random_uniform(d_avail) << MALLOC_MINSHIFT)); 493 494 rbytes_init(d); 495 d->regions_free = d->regions_total = MALLOC_INITIAL_REGIONS; 496 regioninfo_size = d->regions_total * sizeof(struct region_info); 497 d->r = MMAP(regioninfo_size, mmap_flag); 498 if (d->r == MAP_FAILED) { 499 d->regions_total = 0; 500 wrterror(NULL, "malloc init mmap failed"); 501 } 502 for (i = 0; i <= MALLOC_MAXSHIFT; i++) { 503 LIST_INIT(&d->chunk_info_list[i]); 504 for (j = 0; j < MALLOC_CHUNK_LISTS; j++) 505 LIST_INIT(&d->chunk_dir[i][j]); 506 } 507 STATS_ADD(d->malloc_used, regioninfo_size + 3 * MALLOC_PAGESIZE); 508 d->mmap_flag = mmap_flag; 509 d->malloc_junk = mopts.def_malloc_junk; 510 d->malloc_cache = mopts.def_malloc_cache; 511 d->canary1 = mopts.malloc_canary ^ (u_int32_t)(uintptr_t)d; 512 d->canary2 = ~d->canary1; 513 514 *dp = d; 515 } 516 517 static int 518 omalloc_grow(struct dir_info *d) 519 { 520 size_t newtotal; 521 size_t newsize; 522 size_t mask; 523 size_t i; 524 struct region_info *p; 525 526 if (d->regions_total > SIZE_MAX / sizeof(struct region_info) / 2) 527 return 1; 528 529 newtotal = d->regions_total * 2; 530 newsize = newtotal * sizeof(struct region_info); 531 mask = newtotal - 1; 532 533 p = MMAP(newsize, d->mmap_flag); 534 if (p == MAP_FAILED) 535 return 1; 536 537 STATS_ADD(d->malloc_used, newsize); 538 STATS_ZERO(d->inserts); 539 STATS_ZERO(d->insert_collisions); 540 for (i = 0; i < d->regions_total; i++) { 541 void *q = d->r[i].p; 542 if (q != NULL) { 543 size_t index = hash(q) & mask; 544 STATS_INC(d->inserts); 545 while (p[index].p != NULL) { 546 index = (index - 1) & mask; 547 STATS_INC(d->insert_collisions); 548 } 549 p[index] = d->r[i]; 550 } 551 } 552 /* avoid pages containing meta info to end up in cache */ 553 if (munmap(d->r, d->regions_total * sizeof(struct region_info))) 554 wrterror(d, "munmap %p", (void *)d->r); 555 else 556 STATS_SUB(d->malloc_used, 557 d->regions_total * sizeof(struct region_info)); 558 d->regions_free = d->regions_free + d->regions_total; 559 d->regions_total = newtotal; 560 d->r = p; 561 return 0; 562 } 563 564 /* 565 * The hashtable uses the assumption that p is never NULL. This holds since 566 * non-MAP_FIXED mappings with hint 0 start at BRKSIZ. 567 */ 568 static int 569 insert(struct dir_info *d, void *p, size_t sz, void *f) 570 { 571 size_t index; 572 size_t mask; 573 void *q; 574 575 if (d->regions_free * 4 < d->regions_total) { 576 if (omalloc_grow(d)) 577 return 1; 578 } 579 mask = d->regions_total - 1; 580 index = hash(p) & mask; 581 q = d->r[index].p; 582 STATS_INC(d->inserts); 583 while (q != NULL) { 584 index = (index - 1) & mask; 585 q = d->r[index].p; 586 STATS_INC(d->insert_collisions); 587 } 588 d->r[index].p = p; 589 d->r[index].size = sz; 590 #ifdef MALLOC_STATS 591 d->r[index].f = f; 592 #endif 593 d->regions_free--; 594 return 0; 595 } 596 597 static struct region_info * 598 find(struct dir_info *d, void *p) 599 { 600 size_t index; 601 size_t mask = d->regions_total - 1; 602 void *q, *r; 603 604 if (mopts.malloc_canary != (d->canary1 ^ (u_int32_t)(uintptr_t)d) || 605 d->canary1 != ~d->canary2) 606 wrterror(d, "internal struct corrupt"); 607 p = MASK_POINTER(p); 608 index = hash(p) & mask; 609 r = d->r[index].p; 610 q = MASK_POINTER(r); 611 STATS_INC(d->finds); 612 while (q != p && r != NULL) { 613 index = (index - 1) & mask; 614 r = d->r[index].p; 615 q = MASK_POINTER(r); 616 STATS_INC(d->find_collisions); 617 } 618 return (q == p && r != NULL) ? &d->r[index] : NULL; 619 } 620 621 static void 622 delete(struct dir_info *d, struct region_info *ri) 623 { 624 /* algorithm R, Knuth Vol III section 6.4 */ 625 size_t mask = d->regions_total - 1; 626 size_t i, j, r; 627 628 if (d->regions_total & (d->regions_total - 1)) 629 wrterror(d, "regions_total not 2^x"); 630 d->regions_free++; 631 STATS_INC(d->deletes); 632 633 i = ri - d->r; 634 for (;;) { 635 d->r[i].p = NULL; 636 d->r[i].size = 0; 637 j = i; 638 for (;;) { 639 i = (i - 1) & mask; 640 if (d->r[i].p == NULL) 641 return; 642 r = hash(d->r[i].p) & mask; 643 if ((i <= r && r < j) || (r < j && j < i) || 644 (j < i && i <= r)) 645 continue; 646 d->r[j] = d->r[i]; 647 STATS_INC(d->delete_moves); 648 break; 649 } 650 651 } 652 } 653 654 /* 655 * Cache maintenance. We keep at most malloc_cache pages cached. 656 * If the cache is becoming full, unmap pages in the cache for real, 657 * and then add the region to the cache 658 * Opposed to the regular region data structure, the sizes in the 659 * cache are in MALLOC_PAGESIZE units. 660 */ 661 static void 662 unmap(struct dir_info *d, void *p, size_t sz, size_t clear, int junk) 663 { 664 size_t psz = sz >> MALLOC_PAGESHIFT; 665 size_t rsz; 666 struct region_info *r; 667 u_int i, offset, mask; 668 669 if (sz != PAGEROUND(sz)) 670 wrterror(d, "munmap round"); 671 672 rsz = d->malloc_cache - d->free_regions_size; 673 674 /* 675 * normally the cache holds recently freed regions, but if the region 676 * to unmap is larger than the cache size or we're clearing and the 677 * cache is full, just munmap 678 */ 679 if (psz > d->malloc_cache || (clear > 0 && rsz == 0)) { 680 i = munmap(p, sz); 681 if (i) 682 wrterror(d, "munmap %p", p); 683 STATS_SUB(d->malloc_used, sz); 684 return; 685 } 686 offset = getrbyte(d); 687 mask = d->malloc_cache - 1; 688 if (psz > rsz) { 689 size_t tounmap = psz - rsz; 690 for (i = 0; ; i++) { 691 r = &d->free_regions[(i + offset) & mask]; 692 if (r->p != NULL) { 693 rsz = r->size << MALLOC_PAGESHIFT; 694 if (munmap(r->p, rsz)) 695 wrterror(d, "munmap %p", r->p); 696 r->p = NULL; 697 if (tounmap > r->size) 698 tounmap -= r->size; 699 else 700 tounmap = 0; 701 d->free_regions_size -= r->size; 702 STATS_SUB(d->malloc_used, rsz); 703 if (tounmap == 0) { 704 offset = i; 705 break; 706 } 707 } 708 } 709 } 710 for (i = 0; ; i++) { 711 r = &d->free_regions[(i + offset) & mask]; 712 if (r->p == NULL) { 713 if (clear > 0) 714 memset(p, 0, clear); 715 if (junk && !mopts.malloc_freeunmap) { 716 size_t amt = junk == 1 ? MALLOC_MAXCHUNK : sz; 717 memset(p, SOME_FREEJUNK, amt); 718 } 719 if (mopts.malloc_freeunmap) 720 mprotect(p, sz, PROT_NONE); 721 r->p = p; 722 r->size = psz; 723 d->free_regions_size += psz; 724 break; 725 } 726 } 727 if (d->free_regions_size > d->malloc_cache) 728 wrterror(d, "malloc cache overflow"); 729 } 730 731 static void * 732 map(struct dir_info *d, size_t sz, int zero_fill) 733 { 734 size_t psz = sz >> MALLOC_PAGESHIFT; 735 struct region_info *r, *big = NULL; 736 u_int i; 737 void *p; 738 739 if (mopts.malloc_canary != (d->canary1 ^ (u_int32_t)(uintptr_t)d) || 740 d->canary1 != ~d->canary2) 741 wrterror(d, "internal struct corrupt"); 742 if (sz != PAGEROUND(sz)) 743 wrterror(d, "map round"); 744 745 if (psz > d->free_regions_size) { 746 _MALLOC_LEAVE(d); 747 p = MMAP(sz, d->mmap_flag); 748 _MALLOC_ENTER(d); 749 if (p != MAP_FAILED) 750 STATS_ADD(d->malloc_used, sz); 751 /* zero fill not needed */ 752 return p; 753 } 754 for (i = 0; i < d->malloc_cache; i++) { 755 r = &d->free_regions[(i + d->rotor) & (d->malloc_cache - 1)]; 756 if (r->p != NULL) { 757 if (r->size == psz) { 758 p = r->p; 759 r->p = NULL; 760 d->free_regions_size -= psz; 761 if (mopts.malloc_freeunmap) 762 mprotect(p, sz, PROT_READ | PROT_WRITE); 763 if (zero_fill) 764 memset(p, 0, sz); 765 else if (d->malloc_junk == 2 && 766 mopts.malloc_freeunmap) 767 memset(p, SOME_FREEJUNK, sz); 768 d->rotor += i + 1; 769 return p; 770 } else if (r->size > psz) 771 big = r; 772 } 773 } 774 if (big != NULL) { 775 r = big; 776 p = r->p; 777 r->p = (char *)r->p + (psz << MALLOC_PAGESHIFT); 778 if (mopts.malloc_freeunmap) 779 mprotect(p, sz, PROT_READ | PROT_WRITE); 780 r->size -= psz; 781 d->free_regions_size -= psz; 782 if (zero_fill) 783 memset(p, 0, sz); 784 else if (d->malloc_junk == 2 && mopts.malloc_freeunmap) 785 memset(p, SOME_FREEJUNK, sz); 786 return p; 787 } 788 if (d->free_regions_size > d->malloc_cache) 789 wrterror(d, "malloc cache"); 790 _MALLOC_LEAVE(d); 791 p = MMAP(sz, d->mmap_flag); 792 _MALLOC_ENTER(d); 793 if (p != MAP_FAILED) 794 STATS_ADD(d->malloc_used, sz); 795 /* zero fill not needed */ 796 return p; 797 } 798 799 static void 800 init_chunk_info(struct dir_info *d, struct chunk_info *p, int bits) 801 { 802 int i; 803 804 if (bits == 0) { 805 p->shift = MALLOC_MINSHIFT; 806 p->total = p->free = MALLOC_PAGESIZE >> p->shift; 807 p->size = 0; 808 p->offset = 0xdead; 809 } else { 810 p->shift = bits; 811 p->total = p->free = MALLOC_PAGESIZE >> p->shift; 812 p->size = 1U << bits; 813 p->offset = howmany(p->total, MALLOC_BITS); 814 } 815 p->canary = (u_short)d->canary1; 816 817 /* set all valid bits in the bitmap */ 818 i = p->total - 1; 819 memset(p->bits, 0xff, sizeof(p->bits[0]) * (i / MALLOC_BITS)); 820 p->bits[i / MALLOC_BITS] = (2U << (i % MALLOC_BITS)) - 1; 821 } 822 823 static struct chunk_info * 824 alloc_chunk_info(struct dir_info *d, int bits) 825 { 826 struct chunk_info *p; 827 828 if (LIST_EMPTY(&d->chunk_info_list[bits])) { 829 size_t size, count, i; 830 char *q; 831 832 if (bits == 0) 833 count = MALLOC_PAGESIZE / MALLOC_MINSIZE; 834 else 835 count = MALLOC_PAGESIZE >> bits; 836 837 size = howmany(count, MALLOC_BITS); 838 size = sizeof(struct chunk_info) + (size - 1) * sizeof(u_short); 839 if (mopts.chunk_canaries) 840 size += count * sizeof(u_short); 841 size = _ALIGN(size); 842 843 q = MMAP(MALLOC_PAGESIZE, d->mmap_flag); 844 if (q == MAP_FAILED) 845 return NULL; 846 STATS_ADD(d->malloc_used, MALLOC_PAGESIZE); 847 count = MALLOC_PAGESIZE / size; 848 849 for (i = 0; i < count; i++, q += size) { 850 p = (struct chunk_info *)q; 851 LIST_INSERT_HEAD(&d->chunk_info_list[bits], p, entries); 852 } 853 } 854 p = LIST_FIRST(&d->chunk_info_list[bits]); 855 LIST_REMOVE(p, entries); 856 if (p->shift == 0) 857 init_chunk_info(d, p, bits); 858 return p; 859 } 860 861 /* 862 * Allocate a page of chunks 863 */ 864 static struct chunk_info * 865 omalloc_make_chunks(struct dir_info *d, int bits, int listnum) 866 { 867 struct chunk_info *bp; 868 void *pp; 869 870 /* Allocate a new bucket */ 871 pp = map(d, MALLOC_PAGESIZE, 0); 872 if (pp == MAP_FAILED) 873 return NULL; 874 875 /* memory protect the page allocated in the malloc(0) case */ 876 if (bits == 0 && mprotect(pp, MALLOC_PAGESIZE, PROT_NONE) == -1) 877 goto err; 878 879 bp = alloc_chunk_info(d, bits); 880 if (bp == NULL) 881 goto err; 882 bp->page = pp; 883 884 if (insert(d, (void *)((uintptr_t)pp | (bits + 1)), (uintptr_t)bp, 885 NULL)) 886 goto err; 887 LIST_INSERT_HEAD(&d->chunk_dir[bits][listnum], bp, entries); 888 return bp; 889 890 err: 891 unmap(d, pp, MALLOC_PAGESIZE, 0, d->malloc_junk); 892 return NULL; 893 } 894 895 static int 896 find_chunksize(size_t size) 897 { 898 int r; 899 900 /* malloc(0) is special */ 901 if (size == 0) 902 return 0; 903 904 if (size < MALLOC_MINSIZE) 905 size = MALLOC_MINSIZE; 906 size--; 907 908 r = MALLOC_MINSHIFT; 909 while (size >> r) 910 r++; 911 return r; 912 } 913 914 static void 915 fill_canary(char *ptr, size_t sz, size_t allocated) 916 { 917 size_t check_sz = allocated - sz; 918 919 if (check_sz > CHUNK_CHECK_LENGTH) 920 check_sz = CHUNK_CHECK_LENGTH; 921 memset(ptr + sz, SOME_JUNK, check_sz); 922 } 923 924 /* 925 * Allocate a chunk 926 */ 927 static void * 928 malloc_bytes(struct dir_info *d, size_t size, void *f) 929 { 930 u_int i, r; 931 int j, listnum; 932 size_t k; 933 u_short *lp; 934 struct chunk_info *bp; 935 void *p; 936 937 if (mopts.malloc_canary != (d->canary1 ^ (u_int32_t)(uintptr_t)d) || 938 d->canary1 != ~d->canary2) 939 wrterror(d, "internal struct corrupt"); 940 941 j = find_chunksize(size); 942 943 r = ((u_int)getrbyte(d) << 8) | getrbyte(d); 944 listnum = r % MALLOC_CHUNK_LISTS; 945 /* If it's empty, make a page more of that size chunks */ 946 if ((bp = LIST_FIRST(&d->chunk_dir[j][listnum])) == NULL) { 947 bp = omalloc_make_chunks(d, j, listnum); 948 if (bp == NULL) 949 return NULL; 950 } 951 952 if (bp->canary != (u_short)d->canary1) 953 wrterror(d, "chunk info corrupted"); 954 955 i = (r / MALLOC_CHUNK_LISTS) & (bp->total - 1); 956 957 /* start somewhere in a short */ 958 lp = &bp->bits[i / MALLOC_BITS]; 959 if (*lp) { 960 j = i % MALLOC_BITS; 961 k = ffs(*lp >> j); 962 if (k != 0) { 963 k += j - 1; 964 goto found; 965 } 966 } 967 /* no bit halfway, go to next full short */ 968 i /= MALLOC_BITS; 969 for (;;) { 970 if (++i >= bp->total / MALLOC_BITS) 971 i = 0; 972 lp = &bp->bits[i]; 973 if (*lp) { 974 k = ffs(*lp) - 1; 975 break; 976 } 977 } 978 found: 979 #ifdef MALLOC_STATS 980 if (i == 0 && k == 0) { 981 struct region_info *r = find(d, bp->page); 982 r->f = f; 983 } 984 #endif 985 986 *lp ^= 1 << k; 987 988 /* If there are no more free, remove from free-list */ 989 if (--bp->free == 0) 990 LIST_REMOVE(bp, entries); 991 992 /* Adjust to the real offset of that chunk */ 993 k += (lp - bp->bits) * MALLOC_BITS; 994 995 if (mopts.chunk_canaries && size > 0) 996 bp->bits[bp->offset + k] = size; 997 998 k <<= bp->shift; 999 1000 p = (char *)bp->page + k; 1001 if (bp->size > 0) { 1002 if (d->malloc_junk == 2) 1003 memset(p, SOME_JUNK, bp->size); 1004 else if (mopts.chunk_canaries) 1005 fill_canary(p, size, bp->size); 1006 } 1007 return p; 1008 } 1009 1010 static void 1011 validate_canary(struct dir_info *d, u_char *ptr, size_t sz, size_t allocated) 1012 { 1013 size_t check_sz = allocated - sz; 1014 u_char *p, *q; 1015 1016 if (check_sz > CHUNK_CHECK_LENGTH) 1017 check_sz = CHUNK_CHECK_LENGTH; 1018 p = ptr + sz; 1019 q = p + check_sz; 1020 1021 while (p < q) { 1022 if (*p != SOME_JUNK) { 1023 wrterror(d, "chunk canary corrupted %p %#tx@%#zx%s", 1024 ptr, p - ptr, sz, 1025 *p == SOME_FREEJUNK ? " (double free?)" : ""); 1026 } 1027 p++; 1028 } 1029 } 1030 1031 static uint32_t 1032 find_chunknum(struct dir_info *d, struct chunk_info *info, void *ptr, int check) 1033 { 1034 uint32_t chunknum; 1035 1036 if (info->canary != (u_short)d->canary1) 1037 wrterror(d, "chunk info corrupted"); 1038 1039 /* Find the chunk number on the page */ 1040 chunknum = ((uintptr_t)ptr & MALLOC_PAGEMASK) >> info->shift; 1041 1042 if ((uintptr_t)ptr & ((1U << (info->shift)) - 1)) 1043 wrterror(d, "modified chunk-pointer %p", ptr); 1044 if (info->bits[chunknum / MALLOC_BITS] & 1045 (1U << (chunknum % MALLOC_BITS))) 1046 wrterror(d, "chunk is already free %p", ptr); 1047 if (check && info->size > 0) { 1048 validate_canary(d, ptr, info->bits[info->offset + chunknum], 1049 info->size); 1050 } 1051 return chunknum; 1052 } 1053 1054 /* 1055 * Free a chunk, and possibly the page it's on, if the page becomes empty. 1056 */ 1057 static void 1058 free_bytes(struct dir_info *d, struct region_info *r, void *ptr) 1059 { 1060 struct chunk_head *mp; 1061 struct chunk_info *info; 1062 uint32_t chunknum; 1063 int listnum; 1064 1065 info = (struct chunk_info *)r->size; 1066 chunknum = find_chunknum(d, info, ptr, 0); 1067 1068 info->bits[chunknum / MALLOC_BITS] |= 1U << (chunknum % MALLOC_BITS); 1069 info->free++; 1070 1071 if (info->free == 1) { 1072 /* Page became non-full */ 1073 listnum = getrbyte(d) % MALLOC_CHUNK_LISTS; 1074 if (info->size != 0) 1075 mp = &d->chunk_dir[info->shift][listnum]; 1076 else 1077 mp = &d->chunk_dir[0][listnum]; 1078 1079 LIST_INSERT_HEAD(mp, info, entries); 1080 return; 1081 } 1082 1083 if (info->free != info->total) 1084 return; 1085 1086 LIST_REMOVE(info, entries); 1087 1088 if (info->size == 0 && !mopts.malloc_freeunmap) 1089 mprotect(info->page, MALLOC_PAGESIZE, PROT_READ | PROT_WRITE); 1090 unmap(d, info->page, MALLOC_PAGESIZE, 0, 0); 1091 1092 delete(d, r); 1093 if (info->size != 0) 1094 mp = &d->chunk_info_list[info->shift]; 1095 else 1096 mp = &d->chunk_info_list[0]; 1097 LIST_INSERT_HEAD(mp, info, entries); 1098 } 1099 1100 1101 1102 static void * 1103 omalloc(struct dir_info *pool, size_t sz, int zero_fill, void *f) 1104 { 1105 void *p; 1106 size_t psz; 1107 1108 if (sz > MALLOC_MAXCHUNK) { 1109 if (sz >= SIZE_MAX - mopts.malloc_guard - MALLOC_PAGESIZE) { 1110 errno = ENOMEM; 1111 return NULL; 1112 } 1113 sz += mopts.malloc_guard; 1114 psz = PAGEROUND(sz); 1115 p = map(pool, psz, zero_fill); 1116 if (p == MAP_FAILED) { 1117 errno = ENOMEM; 1118 return NULL; 1119 } 1120 if (insert(pool, p, sz, f)) { 1121 unmap(pool, p, psz, 0, 0); 1122 errno = ENOMEM; 1123 return NULL; 1124 } 1125 if (mopts.malloc_guard) { 1126 if (mprotect((char *)p + psz - mopts.malloc_guard, 1127 mopts.malloc_guard, PROT_NONE)) 1128 wrterror(pool, "mprotect"); 1129 STATS_ADD(pool->malloc_guarded, mopts.malloc_guard); 1130 } 1131 1132 if (MALLOC_MOVE_COND(sz)) { 1133 /* fill whole allocation */ 1134 if (pool->malloc_junk == 2) 1135 memset(p, SOME_JUNK, psz - mopts.malloc_guard); 1136 /* shift towards the end */ 1137 p = MALLOC_MOVE(p, sz); 1138 /* fill zeros if needed and overwritten above */ 1139 if (zero_fill && pool->malloc_junk == 2) 1140 memset(p, 0, sz - mopts.malloc_guard); 1141 } else { 1142 if (pool->malloc_junk == 2) { 1143 if (zero_fill) 1144 memset((char *)p + sz - mopts.malloc_guard, 1145 SOME_JUNK, psz - sz); 1146 else 1147 memset(p, SOME_JUNK, 1148 psz - mopts.malloc_guard); 1149 } else if (mopts.chunk_canaries) 1150 fill_canary(p, sz - mopts.malloc_guard, 1151 psz - mopts.malloc_guard); 1152 } 1153 1154 } else { 1155 /* takes care of SOME_JUNK */ 1156 p = malloc_bytes(pool, sz, f); 1157 if (zero_fill && p != NULL && sz > 0) 1158 memset(p, 0, sz); 1159 } 1160 1161 return p; 1162 } 1163 1164 /* 1165 * Common function for handling recursion. Only 1166 * print the error message once, to avoid making the problem 1167 * potentially worse. 1168 */ 1169 static void 1170 malloc_recurse(struct dir_info *d) 1171 { 1172 static int noprint; 1173 1174 if (noprint == 0) { 1175 noprint = 1; 1176 wrterror(d, "recursive call"); 1177 } 1178 d->active--; 1179 _MALLOC_UNLOCK(d->mutex); 1180 errno = EDEADLK; 1181 } 1182 1183 void 1184 _malloc_init(int from_rthreads) 1185 { 1186 u_int i, nmutexes; 1187 struct dir_info *d; 1188 1189 _MALLOC_LOCK(1); 1190 if (!from_rthreads && mopts.malloc_pool[1]) { 1191 _MALLOC_UNLOCK(1); 1192 return; 1193 } 1194 if (!mopts.malloc_canary) 1195 omalloc_init(); 1196 1197 nmutexes = from_rthreads ? mopts.malloc_mutexes : 2; 1198 if (((uintptr_t)&malloc_readonly & MALLOC_PAGEMASK) == 0) 1199 mprotect(&malloc_readonly, sizeof(malloc_readonly), 1200 PROT_READ | PROT_WRITE); 1201 for (i = 0; i < nmutexes; i++) { 1202 if (mopts.malloc_pool[i]) 1203 continue; 1204 if (i == 0) { 1205 omalloc_poolinit(&d, MAP_CONCEAL); 1206 d->malloc_junk = 2; 1207 d->malloc_cache = 0; 1208 } else { 1209 omalloc_poolinit(&d, 0); 1210 d->malloc_junk = mopts.def_malloc_junk; 1211 d->malloc_cache = mopts.def_malloc_cache; 1212 } 1213 d->mutex = i; 1214 mopts.malloc_pool[i] = d; 1215 } 1216 1217 if (from_rthreads) 1218 mopts.malloc_mt = 1; 1219 else 1220 mopts.internal_funcs = 1; 1221 1222 /* 1223 * Options have been set and will never be reset. 1224 * Prevent further tampering with them. 1225 */ 1226 if (((uintptr_t)&malloc_readonly & MALLOC_PAGEMASK) == 0) 1227 mprotect(&malloc_readonly, sizeof(malloc_readonly), PROT_READ); 1228 _MALLOC_UNLOCK(1); 1229 } 1230 DEF_STRONG(_malloc_init); 1231 1232 #define PROLOGUE(p, fn) \ 1233 d = (p); \ 1234 if (d == NULL) { \ 1235 _malloc_init(0); \ 1236 d = (p); \ 1237 } \ 1238 _MALLOC_LOCK(d->mutex); \ 1239 d->func = fn; \ 1240 if (d->active++) { \ 1241 malloc_recurse(d); \ 1242 return NULL; \ 1243 } \ 1244 1245 #define EPILOGUE() \ 1246 d->active--; \ 1247 _MALLOC_UNLOCK(d->mutex); \ 1248 if (r == NULL && mopts.malloc_xmalloc) \ 1249 wrterror(d, "out of memory"); \ 1250 if (r != NULL) \ 1251 errno = saved_errno; \ 1252 1253 void * 1254 malloc(size_t size) 1255 { 1256 void *r; 1257 struct dir_info *d; 1258 int saved_errno = errno; 1259 1260 PROLOGUE(getpool(), "malloc") 1261 r = omalloc(d, size, 0, CALLER); 1262 EPILOGUE() 1263 return r; 1264 } 1265 /*DEF_STRONG(malloc);*/ 1266 1267 void * 1268 malloc_conceal(size_t size) 1269 { 1270 void *r; 1271 struct dir_info *d; 1272 int saved_errno = errno; 1273 1274 PROLOGUE(mopts.malloc_pool[0], "malloc_conceal") 1275 r = omalloc(d, size, 0, CALLER); 1276 EPILOGUE() 1277 return r; 1278 } 1279 DEF_WEAK(malloc_conceal); 1280 1281 static void 1282 validate_junk(struct dir_info *pool, void *p) 1283 { 1284 struct region_info *r; 1285 size_t byte, sz; 1286 1287 if (p == NULL) 1288 return; 1289 r = find(pool, p); 1290 if (r == NULL) 1291 wrterror(pool, "bogus pointer in validate_junk %p", p); 1292 REALSIZE(sz, r); 1293 if (sz > CHUNK_CHECK_LENGTH) 1294 sz = CHUNK_CHECK_LENGTH; 1295 for (byte = 0; byte < sz; byte++) { 1296 if (((unsigned char *)p)[byte] != SOME_FREEJUNK) 1297 wrterror(pool, "use after free %p", p); 1298 } 1299 } 1300 1301 1302 static struct region_info * 1303 findpool(void *p, struct dir_info *argpool, struct dir_info **foundpool, 1304 char **saved_function) 1305 { 1306 struct dir_info *pool = argpool; 1307 struct region_info *r = find(pool, p); 1308 1309 STATS_INC(pool->pool_searches); 1310 if (r == NULL) { 1311 u_int i, nmutexes; 1312 1313 nmutexes = mopts.malloc_mt ? mopts.malloc_mutexes : 2; 1314 STATS_INC(pool->other_pool); 1315 for (i = 1; i < nmutexes; i++) { 1316 u_int j = (argpool->mutex + i) & (nmutexes - 1); 1317 1318 pool->active--; 1319 _MALLOC_UNLOCK(pool->mutex); 1320 pool = mopts.malloc_pool[j]; 1321 _MALLOC_LOCK(pool->mutex); 1322 pool->active++; 1323 r = find(pool, p); 1324 if (r != NULL) { 1325 *saved_function = pool->func; 1326 pool->func = argpool->func; 1327 break; 1328 } 1329 } 1330 if (r == NULL) 1331 wrterror(argpool, "bogus pointer (double free?) %p", p); 1332 } 1333 *foundpool = pool; 1334 return r; 1335 } 1336 1337 static void 1338 ofree(struct dir_info **argpool, void *p, int clear, int check, size_t argsz) 1339 { 1340 struct region_info *r; 1341 struct dir_info *pool; 1342 char *saved_function; 1343 size_t sz; 1344 1345 r = findpool(p, *argpool, &pool, &saved_function); 1346 1347 REALSIZE(sz, r); 1348 if (pool->mmap_flag) { 1349 clear = 1; 1350 if (!check) 1351 argsz = sz; 1352 } 1353 if (check) { 1354 if (sz <= MALLOC_MAXCHUNK) { 1355 if (mopts.chunk_canaries && sz > 0) { 1356 struct chunk_info *info = 1357 (struct chunk_info *)r->size; 1358 uint32_t chunknum = 1359 find_chunknum(pool, info, p, 0); 1360 1361 if (info->bits[info->offset + chunknum] < argsz) 1362 wrterror(pool, "recorded size %hu" 1363 " < %zu", 1364 info->bits[info->offset + chunknum], 1365 argsz); 1366 } else { 1367 if (sz < argsz) 1368 wrterror(pool, "chunk size %zu < %zu", 1369 sz, argsz); 1370 } 1371 } else if (sz - mopts.malloc_guard < argsz) { 1372 wrterror(pool, "recorded size %zu < %zu", 1373 sz - mopts.malloc_guard, argsz); 1374 } 1375 } 1376 if (sz > MALLOC_MAXCHUNK) { 1377 if (!MALLOC_MOVE_COND(sz)) { 1378 if (r->p != p) 1379 wrterror(pool, "bogus pointer %p", p); 1380 if (mopts.chunk_canaries) 1381 validate_canary(pool, p, 1382 sz - mopts.malloc_guard, 1383 PAGEROUND(sz - mopts.malloc_guard)); 1384 } else { 1385 /* shifted towards the end */ 1386 if (p != MALLOC_MOVE(r->p, sz)) 1387 wrterror(pool, "bogus moved pointer %p", p); 1388 p = r->p; 1389 } 1390 if (mopts.malloc_guard) { 1391 if (sz < mopts.malloc_guard) 1392 wrterror(pool, "guard size"); 1393 if (!mopts.malloc_freeunmap) { 1394 if (mprotect((char *)p + PAGEROUND(sz) - 1395 mopts.malloc_guard, mopts.malloc_guard, 1396 PROT_READ | PROT_WRITE)) 1397 wrterror(pool, "mprotect"); 1398 } 1399 STATS_SUB(pool->malloc_guarded, mopts.malloc_guard); 1400 } 1401 unmap(pool, p, PAGEROUND(sz), clear ? argsz : 0, 1402 pool->malloc_junk); 1403 delete(pool, r); 1404 } else { 1405 /* Validate and optionally canary check */ 1406 struct chunk_info *info = (struct chunk_info *)r->size; 1407 find_chunknum(pool, info, p, mopts.chunk_canaries); 1408 if (!clear) { 1409 void *tmp; 1410 int i; 1411 1412 if (mopts.malloc_freecheck) { 1413 for (i = 0; i <= MALLOC_DELAYED_CHUNK_MASK; i++) 1414 if (p == pool->delayed_chunks[i]) 1415 wrterror(pool, 1416 "double free %p", p); 1417 } 1418 if (pool->malloc_junk && sz > 0) 1419 memset(p, SOME_FREEJUNK, sz); 1420 i = getrbyte(pool) & MALLOC_DELAYED_CHUNK_MASK; 1421 tmp = p; 1422 p = pool->delayed_chunks[i]; 1423 if (tmp == p) 1424 wrterror(pool, "double free %p", tmp); 1425 pool->delayed_chunks[i] = tmp; 1426 if (pool->malloc_junk) 1427 validate_junk(pool, p); 1428 } else if (argsz > 0) 1429 memset(p, 0, argsz); 1430 if (p != NULL) { 1431 r = find(pool, p); 1432 if (r == NULL) 1433 wrterror(pool, 1434 "bogus pointer (double free?) %p", p); 1435 free_bytes(pool, r, p); 1436 } 1437 } 1438 1439 if (*argpool != pool) { 1440 pool->func = saved_function; 1441 *argpool = pool; 1442 } 1443 } 1444 1445 void 1446 free(void *ptr) 1447 { 1448 struct dir_info *d; 1449 int saved_errno = errno; 1450 1451 /* This is legal. */ 1452 if (ptr == NULL) 1453 return; 1454 1455 d = getpool(); 1456 if (d == NULL) 1457 wrterror(d, "free() called before allocation"); 1458 _MALLOC_LOCK(d->mutex); 1459 d->func = "free"; 1460 if (d->active++) { 1461 malloc_recurse(d); 1462 return; 1463 } 1464 ofree(&d, ptr, 0, 0, 0); 1465 d->active--; 1466 _MALLOC_UNLOCK(d->mutex); 1467 errno = saved_errno; 1468 } 1469 /*DEF_STRONG(free);*/ 1470 1471 static void 1472 freezero_p(void *ptr, size_t sz) 1473 { 1474 explicit_bzero(ptr, sz); 1475 free(ptr); 1476 } 1477 1478 void 1479 freezero(void *ptr, size_t sz) 1480 { 1481 struct dir_info *d; 1482 int saved_errno = errno; 1483 1484 /* This is legal. */ 1485 if (ptr == NULL) 1486 return; 1487 1488 if (!mopts.internal_funcs) { 1489 freezero_p(ptr, sz); 1490 return; 1491 } 1492 1493 d = getpool(); 1494 if (d == NULL) 1495 wrterror(d, "freezero() called before allocation"); 1496 _MALLOC_LOCK(d->mutex); 1497 d->func = "freezero"; 1498 if (d->active++) { 1499 malloc_recurse(d); 1500 return; 1501 } 1502 ofree(&d, ptr, 1, 1, sz); 1503 d->active--; 1504 _MALLOC_UNLOCK(d->mutex); 1505 errno = saved_errno; 1506 } 1507 DEF_WEAK(freezero); 1508 1509 static void * 1510 orealloc(struct dir_info **argpool, void *p, size_t newsz, void *f) 1511 { 1512 struct region_info *r; 1513 struct dir_info *pool; 1514 char *saved_function; 1515 struct chunk_info *info; 1516 size_t oldsz, goldsz, gnewsz; 1517 void *q, *ret; 1518 uint32_t chunknum; 1519 int forced; 1520 1521 if (p == NULL) 1522 return omalloc(*argpool, newsz, 0, f); 1523 1524 if (newsz >= SIZE_MAX - mopts.malloc_guard - MALLOC_PAGESIZE) { 1525 errno = ENOMEM; 1526 return NULL; 1527 } 1528 1529 r = findpool(p, *argpool, &pool, &saved_function); 1530 1531 REALSIZE(oldsz, r); 1532 if (mopts.chunk_canaries && oldsz <= MALLOC_MAXCHUNK) { 1533 info = (struct chunk_info *)r->size; 1534 chunknum = find_chunknum(pool, info, p, 0); 1535 } 1536 1537 goldsz = oldsz; 1538 if (oldsz > MALLOC_MAXCHUNK) { 1539 if (oldsz < mopts.malloc_guard) 1540 wrterror(pool, "guard size"); 1541 oldsz -= mopts.malloc_guard; 1542 } 1543 1544 gnewsz = newsz; 1545 if (gnewsz > MALLOC_MAXCHUNK) 1546 gnewsz += mopts.malloc_guard; 1547 1548 forced = mopts.malloc_realloc || pool->mmap_flag; 1549 if (newsz > MALLOC_MAXCHUNK && oldsz > MALLOC_MAXCHUNK && !forced) { 1550 /* First case: from n pages sized allocation to m pages sized 1551 allocation, m > n */ 1552 size_t roldsz = PAGEROUND(goldsz); 1553 size_t rnewsz = PAGEROUND(gnewsz); 1554 1555 if (rnewsz < roldsz && rnewsz > roldsz / 2 && 1556 roldsz - rnewsz < pool->malloc_cache * MALLOC_PAGESIZE && 1557 !mopts.malloc_guard) { 1558 1559 ret = p; 1560 goto done; 1561 } 1562 1563 if (rnewsz > roldsz) { 1564 /* try to extend existing region */ 1565 if (!mopts.malloc_guard) { 1566 void *hint = (char *)r->p + roldsz; 1567 size_t needed = rnewsz - roldsz; 1568 1569 STATS_INC(pool->cheap_realloc_tries); 1570 q = MQUERY(hint, needed, pool->mmap_flag); 1571 if (q == hint) 1572 q = MMAPA(hint, needed, pool->mmap_flag); 1573 else 1574 q = MAP_FAILED; 1575 if (q == hint) { 1576 STATS_ADD(pool->malloc_used, needed); 1577 if (pool->malloc_junk == 2) 1578 memset(q, SOME_JUNK, needed); 1579 r->size = gnewsz; 1580 if (r->p != p) { 1581 /* old pointer is moved */ 1582 memmove(r->p, p, oldsz); 1583 p = r->p; 1584 } 1585 if (mopts.chunk_canaries) 1586 fill_canary(p, newsz, 1587 PAGEROUND(newsz)); 1588 STATS_SETF(r, f); 1589 STATS_INC(pool->cheap_reallocs); 1590 ret = p; 1591 goto done; 1592 } else if (q != MAP_FAILED) { 1593 if (munmap(q, needed)) 1594 wrterror(pool, "munmap %p", q); 1595 } 1596 } 1597 } else if (rnewsz < roldsz) { 1598 /* shrink number of pages */ 1599 if (mopts.malloc_guard) { 1600 if (mprotect((char *)r->p + rnewsz - 1601 mopts.malloc_guard, mopts.malloc_guard, 1602 PROT_NONE)) 1603 wrterror(pool, "mprotect"); 1604 } 1605 if (munmap((char *)r->p + rnewsz, roldsz - rnewsz)) 1606 wrterror(pool, "munmap %p", (char *)r->p + rnewsz); 1607 r->size = gnewsz; 1608 if (MALLOC_MOVE_COND(gnewsz)) { 1609 void *pp = MALLOC_MOVE(r->p, gnewsz); 1610 memmove(pp, p, newsz); 1611 p = pp; 1612 } else if (mopts.chunk_canaries) 1613 fill_canary(p, newsz, PAGEROUND(newsz)); 1614 STATS_SETF(r, f); 1615 ret = p; 1616 goto done; 1617 } else { 1618 /* number of pages remains the same */ 1619 void *pp = r->p; 1620 1621 r->size = gnewsz; 1622 if (MALLOC_MOVE_COND(gnewsz)) 1623 pp = MALLOC_MOVE(r->p, gnewsz); 1624 if (p != pp) { 1625 memmove(pp, p, oldsz < newsz ? oldsz : newsz); 1626 p = pp; 1627 } 1628 if (p == r->p) { 1629 if (newsz > oldsz && pool->malloc_junk == 2) 1630 memset((char *)p + newsz, SOME_JUNK, 1631 rnewsz - mopts.malloc_guard - 1632 newsz); 1633 if (mopts.chunk_canaries) 1634 fill_canary(p, newsz, PAGEROUND(newsz)); 1635 } 1636 STATS_SETF(r, f); 1637 ret = p; 1638 goto done; 1639 } 1640 } 1641 if (oldsz <= MALLOC_MAXCHUNK && oldsz > 0 && 1642 newsz <= MALLOC_MAXCHUNK && newsz > 0 && 1643 1 << find_chunksize(newsz) == oldsz && !forced) { 1644 /* do not reallocate if new size fits good in existing chunk */ 1645 if (pool->malloc_junk == 2) 1646 memset((char *)p + newsz, SOME_JUNK, oldsz - newsz); 1647 if (mopts.chunk_canaries) { 1648 info->bits[info->offset + chunknum] = newsz; 1649 fill_canary(p, newsz, info->size); 1650 } 1651 STATS_SETF(r, f); 1652 ret = p; 1653 } else if (newsz != oldsz || forced) { 1654 /* create new allocation */ 1655 q = omalloc(pool, newsz, 0, f); 1656 if (q == NULL) { 1657 ret = NULL; 1658 goto done; 1659 } 1660 if (newsz != 0 && oldsz != 0) 1661 memcpy(q, p, oldsz < newsz ? oldsz : newsz); 1662 ofree(&pool, p, 0, 0, 0); 1663 ret = q; 1664 } else { 1665 /* oldsz == newsz */ 1666 if (newsz != 0) 1667 wrterror(pool, "realloc internal inconsistency"); 1668 STATS_SETF(r, f); 1669 ret = p; 1670 } 1671 done: 1672 if (*argpool != pool) { 1673 pool->func = saved_function; 1674 *argpool = pool; 1675 } 1676 return ret; 1677 } 1678 1679 void * 1680 realloc(void *ptr, size_t size) 1681 { 1682 struct dir_info *d; 1683 void *r; 1684 int saved_errno = errno; 1685 1686 PROLOGUE(getpool(), "realloc") 1687 r = orealloc(&d, ptr, size, CALLER); 1688 EPILOGUE() 1689 return r; 1690 } 1691 /*DEF_STRONG(realloc);*/ 1692 1693 /* 1694 * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX 1695 * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW 1696 */ 1697 #define MUL_NO_OVERFLOW (1UL << (sizeof(size_t) * 4)) 1698 1699 void * 1700 calloc(size_t nmemb, size_t size) 1701 { 1702 struct dir_info *d; 1703 void *r; 1704 int saved_errno = errno; 1705 1706 PROLOGUE(getpool(), "calloc") 1707 if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 1708 nmemb > 0 && SIZE_MAX / nmemb < size) { 1709 d->active--; 1710 _MALLOC_UNLOCK(d->mutex); 1711 if (mopts.malloc_xmalloc) 1712 wrterror(d, "out of memory"); 1713 errno = ENOMEM; 1714 return NULL; 1715 } 1716 1717 size *= nmemb; 1718 r = omalloc(d, size, 1, CALLER); 1719 EPILOGUE() 1720 return r; 1721 } 1722 /*DEF_STRONG(calloc);*/ 1723 1724 void * 1725 calloc_conceal(size_t nmemb, size_t size) 1726 { 1727 struct dir_info *d; 1728 void *r; 1729 int saved_errno = errno; 1730 1731 PROLOGUE(mopts.malloc_pool[0], "calloc_conceal") 1732 if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 1733 nmemb > 0 && SIZE_MAX / nmemb < size) { 1734 d->active--; 1735 _MALLOC_UNLOCK(d->mutex); 1736 if (mopts.malloc_xmalloc) 1737 wrterror(d, "out of memory"); 1738 errno = ENOMEM; 1739 return NULL; 1740 } 1741 1742 size *= nmemb; 1743 r = omalloc(d, size, 1, CALLER); 1744 EPILOGUE() 1745 return r; 1746 } 1747 DEF_WEAK(calloc_conceal); 1748 1749 static void * 1750 orecallocarray(struct dir_info **argpool, void *p, size_t oldsize, 1751 size_t newsize, void *f) 1752 { 1753 struct region_info *r; 1754 struct dir_info *pool; 1755 char *saved_function; 1756 void *newptr; 1757 size_t sz; 1758 1759 if (p == NULL) 1760 return omalloc(*argpool, newsize, 1, f); 1761 1762 if (oldsize == newsize) 1763 return p; 1764 1765 r = findpool(p, *argpool, &pool, &saved_function); 1766 1767 REALSIZE(sz, r); 1768 if (sz <= MALLOC_MAXCHUNK) { 1769 if (mopts.chunk_canaries && sz > 0) { 1770 struct chunk_info *info = (struct chunk_info *)r->size; 1771 uint32_t chunknum = find_chunknum(pool, info, p, 0); 1772 1773 if (info->bits[info->offset + chunknum] != oldsize) 1774 wrterror(pool, "recorded old size %hu != %zu", 1775 info->bits[info->offset + chunknum], 1776 oldsize); 1777 } 1778 } else if (oldsize < (sz - mopts.malloc_guard) / 2) 1779 wrterror(pool, "recorded old size %zu != %zu", 1780 sz - mopts.malloc_guard, oldsize); 1781 1782 newptr = omalloc(pool, newsize, 0, f); 1783 if (newptr == NULL) 1784 goto done; 1785 1786 if (newsize > oldsize) { 1787 memcpy(newptr, p, oldsize); 1788 memset((char *)newptr + oldsize, 0, newsize - oldsize); 1789 } else 1790 memcpy(newptr, p, newsize); 1791 1792 ofree(&pool, p, 1, 0, oldsize); 1793 1794 done: 1795 if (*argpool != pool) { 1796 pool->func = saved_function; 1797 *argpool = pool; 1798 } 1799 1800 return newptr; 1801 } 1802 1803 static void * 1804 recallocarray_p(void *ptr, size_t oldnmemb, size_t newnmemb, size_t size) 1805 { 1806 size_t oldsize, newsize; 1807 void *newptr; 1808 1809 if (ptr == NULL) 1810 return calloc(newnmemb, size); 1811 1812 if ((newnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 1813 newnmemb > 0 && SIZE_MAX / newnmemb < size) { 1814 errno = ENOMEM; 1815 return NULL; 1816 } 1817 newsize = newnmemb * size; 1818 1819 if ((oldnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 1820 oldnmemb > 0 && SIZE_MAX / oldnmemb < size) { 1821 errno = EINVAL; 1822 return NULL; 1823 } 1824 oldsize = oldnmemb * size; 1825 1826 /* 1827 * Don't bother too much if we're shrinking just a bit, 1828 * we do not shrink for series of small steps, oh well. 1829 */ 1830 if (newsize <= oldsize) { 1831 size_t d = oldsize - newsize; 1832 1833 if (d < oldsize / 2 && d < MALLOC_PAGESIZE) { 1834 memset((char *)ptr + newsize, 0, d); 1835 return ptr; 1836 } 1837 } 1838 1839 newptr = malloc(newsize); 1840 if (newptr == NULL) 1841 return NULL; 1842 1843 if (newsize > oldsize) { 1844 memcpy(newptr, ptr, oldsize); 1845 memset((char *)newptr + oldsize, 0, newsize - oldsize); 1846 } else 1847 memcpy(newptr, ptr, newsize); 1848 1849 explicit_bzero(ptr, oldsize); 1850 free(ptr); 1851 1852 return newptr; 1853 } 1854 1855 void * 1856 recallocarray(void *ptr, size_t oldnmemb, size_t newnmemb, size_t size) 1857 { 1858 struct dir_info *d; 1859 size_t oldsize = 0, newsize; 1860 void *r; 1861 int saved_errno = errno; 1862 1863 if (!mopts.internal_funcs) 1864 return recallocarray_p(ptr, oldnmemb, newnmemb, size); 1865 1866 PROLOGUE(getpool(), "recallocarray") 1867 1868 if ((newnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 1869 newnmemb > 0 && SIZE_MAX / newnmemb < size) { 1870 d->active--; 1871 _MALLOC_UNLOCK(d->mutex); 1872 if (mopts.malloc_xmalloc) 1873 wrterror(d, "out of memory"); 1874 errno = ENOMEM; 1875 return NULL; 1876 } 1877 newsize = newnmemb * size; 1878 1879 if (ptr != NULL) { 1880 if ((oldnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 1881 oldnmemb > 0 && SIZE_MAX / oldnmemb < size) { 1882 d->active--; 1883 _MALLOC_UNLOCK(d->mutex); 1884 errno = EINVAL; 1885 return NULL; 1886 } 1887 oldsize = oldnmemb * size; 1888 } 1889 1890 r = orecallocarray(&d, ptr, oldsize, newsize, CALLER); 1891 EPILOGUE() 1892 return r; 1893 } 1894 DEF_WEAK(recallocarray); 1895 1896 static void * 1897 mapalign(struct dir_info *d, size_t alignment, size_t sz, int zero_fill) 1898 { 1899 char *p, *q; 1900 1901 if (alignment < MALLOC_PAGESIZE || ((alignment - 1) & alignment) != 0) 1902 wrterror(d, "mapalign bad alignment"); 1903 if (sz != PAGEROUND(sz)) 1904 wrterror(d, "mapalign round"); 1905 1906 /* Allocate sz + alignment bytes of memory, which must include a 1907 * subrange of size bytes that is properly aligned. Unmap the 1908 * other bytes, and then return that subrange. 1909 */ 1910 1911 /* We need sz + alignment to fit into a size_t. */ 1912 if (alignment > SIZE_MAX - sz) 1913 return MAP_FAILED; 1914 1915 p = map(d, sz + alignment, zero_fill); 1916 if (p == MAP_FAILED) 1917 return MAP_FAILED; 1918 q = (char *)(((uintptr_t)p + alignment - 1) & ~(alignment - 1)); 1919 if (q != p) { 1920 if (munmap(p, q - p)) 1921 wrterror(d, "munmap %p", p); 1922 } 1923 if (munmap(q + sz, alignment - (q - p))) 1924 wrterror(d, "munmap %p", q + sz); 1925 STATS_SUB(d->malloc_used, alignment); 1926 1927 return q; 1928 } 1929 1930 static void * 1931 omemalign(struct dir_info *pool, size_t alignment, size_t sz, int zero_fill, 1932 void *f) 1933 { 1934 size_t psz; 1935 void *p; 1936 1937 /* If between half a page and a page, avoid MALLOC_MOVE. */ 1938 if (sz > MALLOC_MAXCHUNK && sz < MALLOC_PAGESIZE) 1939 sz = MALLOC_PAGESIZE; 1940 if (alignment <= MALLOC_PAGESIZE) { 1941 /* 1942 * max(size, alignment) is enough to assure the requested 1943 * alignment, since the allocator always allocates 1944 * power-of-two blocks. 1945 */ 1946 if (sz < alignment) 1947 sz = alignment; 1948 return omalloc(pool, sz, zero_fill, f); 1949 } 1950 1951 if (sz >= SIZE_MAX - mopts.malloc_guard - MALLOC_PAGESIZE) { 1952 errno = ENOMEM; 1953 return NULL; 1954 } 1955 1956 sz += mopts.malloc_guard; 1957 psz = PAGEROUND(sz); 1958 1959 p = mapalign(pool, alignment, psz, zero_fill); 1960 if (p == MAP_FAILED) { 1961 errno = ENOMEM; 1962 return NULL; 1963 } 1964 1965 if (insert(pool, p, sz, f)) { 1966 unmap(pool, p, psz, 0, 0); 1967 errno = ENOMEM; 1968 return NULL; 1969 } 1970 1971 if (mopts.malloc_guard) { 1972 if (mprotect((char *)p + psz - mopts.malloc_guard, 1973 mopts.malloc_guard, PROT_NONE)) 1974 wrterror(pool, "mprotect"); 1975 STATS_ADD(pool->malloc_guarded, mopts.malloc_guard); 1976 } 1977 1978 if (pool->malloc_junk == 2) { 1979 if (zero_fill) 1980 memset((char *)p + sz - mopts.malloc_guard, 1981 SOME_JUNK, psz - sz); 1982 else 1983 memset(p, SOME_JUNK, psz - mopts.malloc_guard); 1984 } else if (mopts.chunk_canaries) 1985 fill_canary(p, sz - mopts.malloc_guard, 1986 psz - mopts.malloc_guard); 1987 1988 return p; 1989 } 1990 1991 int 1992 posix_memalign(void **memptr, size_t alignment, size_t size) 1993 { 1994 struct dir_info *d; 1995 int res, saved_errno = errno; 1996 void *r; 1997 1998 /* Make sure that alignment is a large enough power of 2. */ 1999 if (((alignment - 1) & alignment) != 0 || alignment < sizeof(void *)) 2000 return EINVAL; 2001 2002 d = getpool(); 2003 if (d == NULL) { 2004 _malloc_init(0); 2005 d = getpool(); 2006 } 2007 _MALLOC_LOCK(d->mutex); 2008 d->func = "posix_memalign"; 2009 if (d->active++) { 2010 malloc_recurse(d); 2011 goto err; 2012 } 2013 r = omemalign(d, alignment, size, 0, CALLER); 2014 d->active--; 2015 _MALLOC_UNLOCK(d->mutex); 2016 if (r == NULL) { 2017 if (mopts.malloc_xmalloc) 2018 wrterror(d, "out of memory"); 2019 goto err; 2020 } 2021 errno = saved_errno; 2022 *memptr = r; 2023 return 0; 2024 2025 err: 2026 res = errno; 2027 errno = saved_errno; 2028 return res; 2029 } 2030 /*DEF_STRONG(posix_memalign);*/ 2031 2032 void * 2033 aligned_alloc(size_t alignment, size_t size) 2034 { 2035 struct dir_info *d; 2036 int saved_errno = errno; 2037 void *r; 2038 2039 /* Make sure that alignment is a positive power of 2. */ 2040 if (((alignment - 1) & alignment) != 0 || alignment == 0) { 2041 errno = EINVAL; 2042 return NULL; 2043 }; 2044 /* Per spec, size should be a multiple of alignment */ 2045 if ((size & (alignment - 1)) != 0) { 2046 errno = EINVAL; 2047 return NULL; 2048 } 2049 2050 PROLOGUE(getpool(), "aligned_alloc") 2051 r = omemalign(d, alignment, size, 0, CALLER); 2052 EPILOGUE() 2053 return r; 2054 } 2055 /*DEF_STRONG(aligned_alloc);*/ 2056 2057 #ifdef MALLOC_STATS 2058 2059 struct malloc_leak { 2060 void *f; 2061 size_t total_size; 2062 int count; 2063 }; 2064 2065 struct leaknode { 2066 RBT_ENTRY(leaknode) entry; 2067 struct malloc_leak d; 2068 }; 2069 2070 static inline int 2071 leakcmp(const struct leaknode *e1, const struct leaknode *e2) 2072 { 2073 return e1->d.f < e2->d.f ? -1 : e1->d.f > e2->d.f; 2074 } 2075 2076 static RBT_HEAD(leaktree, leaknode) leakhead; 2077 RBT_PROTOTYPE(leaktree, leaknode, entry, leakcmp); 2078 RBT_GENERATE(leaktree, leaknode, entry, leakcmp); 2079 2080 static void 2081 putleakinfo(void *f, size_t sz, int cnt) 2082 { 2083 struct leaknode key, *p; 2084 static struct leaknode *page; 2085 static int used; 2086 2087 if (cnt == 0 || page == MAP_FAILED) 2088 return; 2089 2090 key.d.f = f; 2091 p = RBT_FIND(leaktree, &leakhead, &key); 2092 if (p == NULL) { 2093 if (page == NULL || 2094 used >= MALLOC_PAGESIZE / sizeof(struct leaknode)) { 2095 page = MMAP(MALLOC_PAGESIZE, 0); 2096 if (page == MAP_FAILED) 2097 return; 2098 used = 0; 2099 } 2100 p = &page[used++]; 2101 p->d.f = f; 2102 p->d.total_size = sz * cnt; 2103 p->d.count = cnt; 2104 RBT_INSERT(leaktree, &leakhead, p); 2105 } else { 2106 p->d.total_size += sz * cnt; 2107 p->d.count += cnt; 2108 } 2109 } 2110 2111 static struct malloc_leak *malloc_leaks; 2112 2113 static void 2114 dump_leaks(int fd) 2115 { 2116 struct leaknode *p; 2117 int i = 0; 2118 2119 dprintf(fd, "Leak report\n"); 2120 dprintf(fd, " f sum # avg\n"); 2121 /* XXX only one page of summary */ 2122 if (malloc_leaks == NULL) 2123 malloc_leaks = MMAP(MALLOC_PAGESIZE, 0); 2124 if (malloc_leaks != MAP_FAILED) 2125 memset(malloc_leaks, 0, MALLOC_PAGESIZE); 2126 RBT_FOREACH(p, leaktree, &leakhead) { 2127 dprintf(fd, "%18p %7zu %6u %6zu\n", p->d.f, 2128 p->d.total_size, p->d.count, p->d.total_size / p->d.count); 2129 if (malloc_leaks == MAP_FAILED || 2130 i >= MALLOC_PAGESIZE / sizeof(struct malloc_leak)) 2131 continue; 2132 malloc_leaks[i].f = p->d.f; 2133 malloc_leaks[i].total_size = p->d.total_size; 2134 malloc_leaks[i].count = p->d.count; 2135 i++; 2136 } 2137 } 2138 2139 static void 2140 dump_chunk(int fd, struct chunk_info *p, void *f, int fromfreelist) 2141 { 2142 while (p != NULL) { 2143 dprintf(fd, "chunk %18p %18p %4d %d/%d\n", 2144 p->page, ((p->bits[0] & 1) ? NULL : f), 2145 p->size, p->free, p->total); 2146 if (!fromfreelist) { 2147 if (p->bits[0] & 1) 2148 putleakinfo(NULL, p->size, p->total - p->free); 2149 else { 2150 putleakinfo(f, p->size, 1); 2151 putleakinfo(NULL, p->size, 2152 p->total - p->free - 1); 2153 } 2154 break; 2155 } 2156 p = LIST_NEXT(p, entries); 2157 if (p != NULL) 2158 dprintf(fd, " "); 2159 } 2160 } 2161 2162 static void 2163 dump_free_chunk_info(int fd, struct dir_info *d) 2164 { 2165 int i, j, count; 2166 struct chunk_info *p; 2167 2168 dprintf(fd, "Free chunk structs:\n"); 2169 for (i = 0; i <= MALLOC_MAXSHIFT; i++) { 2170 count = 0; 2171 LIST_FOREACH(p, &d->chunk_info_list[i], entries) 2172 count++; 2173 for (j = 0; j < MALLOC_CHUNK_LISTS; j++) { 2174 p = LIST_FIRST(&d->chunk_dir[i][j]); 2175 if (p == NULL && count == 0) 2176 continue; 2177 dprintf(fd, "%2d) %3d ", i, count); 2178 if (p != NULL) 2179 dump_chunk(fd, p, NULL, 1); 2180 else 2181 dprintf(fd, "\n"); 2182 } 2183 } 2184 2185 } 2186 2187 static void 2188 dump_free_page_info(int fd, struct dir_info *d) 2189 { 2190 int i; 2191 2192 dprintf(fd, "Free pages cached: %zu\n", d->free_regions_size); 2193 for (i = 0; i < d->malloc_cache; i++) { 2194 if (d->free_regions[i].p != NULL) { 2195 dprintf(fd, "%2d) ", i); 2196 dprintf(fd, "free at %p: %zu\n", 2197 d->free_regions[i].p, d->free_regions[i].size); 2198 } 2199 } 2200 } 2201 2202 static void 2203 malloc_dump1(int fd, int poolno, struct dir_info *d) 2204 { 2205 size_t i, realsize; 2206 2207 dprintf(fd, "Malloc dir of %s pool %d at %p\n", __progname, poolno, d); 2208 if (d == NULL) 2209 return; 2210 dprintf(fd, "J=%d cache=%u Fl=%x\n", 2211 d->malloc_junk, d->malloc_cache, d->mmap_flag); 2212 dprintf(fd, "Region slots free %zu/%zu\n", 2213 d->regions_free, d->regions_total); 2214 dprintf(fd, "Finds %zu/%zu\n", d->finds, d->find_collisions); 2215 dprintf(fd, "Inserts %zu/%zu\n", d->inserts, d->insert_collisions); 2216 dprintf(fd, "Deletes %zu/%zu\n", d->deletes, d->delete_moves); 2217 dprintf(fd, "Cheap reallocs %zu/%zu\n", 2218 d->cheap_reallocs, d->cheap_realloc_tries); 2219 dprintf(fd, "Other pool searches %zu/%zu\n", 2220 d->other_pool, d->pool_searches); 2221 dprintf(fd, "In use %zu\n", d->malloc_used); 2222 dprintf(fd, "Guarded %zu\n", d->malloc_guarded); 2223 dump_free_chunk_info(fd, d); 2224 dump_free_page_info(fd, d); 2225 dprintf(fd, 2226 "slot) hash d type page f size [free/n]\n"); 2227 for (i = 0; i < d->regions_total; i++) { 2228 if (d->r[i].p != NULL) { 2229 size_t h = hash(d->r[i].p) & 2230 (d->regions_total - 1); 2231 dprintf(fd, "%4zx) #%4zx %zd ", 2232 i, h, h - i); 2233 REALSIZE(realsize, &d->r[i]); 2234 if (realsize > MALLOC_MAXCHUNK) { 2235 putleakinfo(d->r[i].f, realsize, 1); 2236 dprintf(fd, 2237 "pages %18p %18p %zu\n", d->r[i].p, 2238 d->r[i].f, realsize); 2239 } else 2240 dump_chunk(fd, 2241 (struct chunk_info *)d->r[i].size, 2242 d->r[i].f, 0); 2243 } 2244 } 2245 dump_leaks(fd); 2246 dprintf(fd, "\n"); 2247 } 2248 2249 void 2250 malloc_dump(int fd, int poolno, struct dir_info *pool) 2251 { 2252 int i; 2253 void *p; 2254 struct region_info *r; 2255 int saved_errno = errno; 2256 2257 if (pool == NULL) 2258 return; 2259 for (i = 0; i < MALLOC_DELAYED_CHUNK_MASK + 1; i++) { 2260 p = pool->delayed_chunks[i]; 2261 if (p == NULL) 2262 continue; 2263 r = find(pool, p); 2264 if (r == NULL) 2265 wrterror(pool, "bogus pointer in malloc_dump %p", p); 2266 free_bytes(pool, r, p); 2267 pool->delayed_chunks[i] = NULL; 2268 } 2269 /* XXX leak when run multiple times */ 2270 RBT_INIT(leaktree, &leakhead); 2271 malloc_dump1(fd, poolno, pool); 2272 errno = saved_errno; 2273 } 2274 DEF_WEAK(malloc_dump); 2275 2276 void 2277 malloc_gdump(int fd) 2278 { 2279 int i; 2280 int saved_errno = errno; 2281 2282 for (i = 0; i < mopts.malloc_mutexes; i++) 2283 malloc_dump(fd, i, mopts.malloc_pool[i]); 2284 2285 errno = saved_errno; 2286 } 2287 DEF_WEAK(malloc_gdump); 2288 2289 static void 2290 malloc_exit(void) 2291 { 2292 int save_errno = errno, fd, i; 2293 2294 fd = open("malloc.out", O_RDWR|O_APPEND); 2295 if (fd != -1) { 2296 dprintf(fd, "******** Start dump %s *******\n", __progname); 2297 dprintf(fd, 2298 "MT=%d M=%u I=%d F=%d U=%d J=%d R=%d X=%d C=%d cache=%u G=%zu\n", 2299 mopts.malloc_mt, mopts.malloc_mutexes, 2300 mopts.internal_funcs, mopts.malloc_freecheck, 2301 mopts.malloc_freeunmap, mopts.def_malloc_junk, 2302 mopts.malloc_realloc, mopts.malloc_xmalloc, 2303 mopts.chunk_canaries, mopts.def_malloc_cache, 2304 mopts.malloc_guard); 2305 2306 for (i = 0; i < mopts.malloc_mutexes; i++) 2307 malloc_dump(fd, i, mopts.malloc_pool[i]); 2308 dprintf(fd, "******** End dump %s *******\n", __progname); 2309 close(fd); 2310 } else 2311 dprintf(STDERR_FILENO, 2312 "malloc() warning: Couldn't dump stats\n"); 2313 errno = save_errno; 2314 } 2315 2316 #endif /* MALLOC_STATS */ 2317