1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim maintainers 2019 - 2021 */
7 /* See the file NOTICE for conditions of use and distribution. */
9 /* Exim gets and frees all its store through these functions. In the original
10 implementation there was a lot of mallocing and freeing of small bits of store.
11 The philosophy has now changed to a scheme which includes the concept of
12 "stacking pools" of store. For the short-lived processes, there isn't any real
13 need to do any garbage collection, but the stack concept allows quick resetting
14 in places where this seems sensible.
16 Obviously the long-running processes (the daemon, the queue runner, and eximon)
17 must take care not to eat store.
19 The following different types of store are recognized:
21 . Long-lived, large blocks: This is implemented by retaining the original
22 malloc/free functions, and it used for permanent working buffers and for
23 getting blocks to cut up for the other types.
25 . Long-lived, small blocks: This is used for blocks that have to survive until
26 the process exits. It is implemented as a stacking pool (POOL_PERM). This is
27 functionally the same as store_malloc(), except that the store can't be
28 freed, but I expect it to be more efficient for handling small blocks.
30 . Short-lived, short blocks: Most of the dynamic store falls into this
31 category. It is implemented as a stacking pool (POOL_MAIN) which is reset
32 after accepting a message when multiple messages are received by a single
33 process. Resetting happens at some other times as well, usually fairly
34 locally after some specific processing that needs working store.
36 . There is a separate pool (POOL_SEARCH) that is used only for lookup storage.
37 This means it can be freed when search_tidyup() is called to close down all
40 - There is another pool (POOL_MESSAGE) used for medium-lifetime objects; within
41 a single message transaction but needed for longer than the use of the main
42 pool permits. Currently this means only receive-time DKIM information.
44 - There is a dedicated pool for configuration data read from the config file(s).
45 Once complete, it is made readonly.
47 - There are pools for each active combination of lookup-quoting, dynamically created.
49 . Orthogonal to the four main pool types, there are two classes of memory: untainted
50 and tainted. The latter is used for values derived from untrusted input, and
51 the string-expansion mechanism refuses to operate on such values (obviously,
52 it can expand an untainted value to return a tainted result). The classes
53 are implemented by duplicating the four pool types. Pool resets are requested
54 against the nontainted sibling and apply to both siblings.
56 Only memory blocks requested for tainted use are regarded as tainted; anything
57 else (including stack auto variables) is untainted. Care is needed when coding
58 to not copy untrusted data into untainted memory, as downstream taint-checks
61 Intermediate layers (eg. the string functions) can test for taint, and use this
62 for ensurinng that results have proper state. For example the
63 string_vformat_trc() routing supporting the string_sprintf() interface will
64 recopy a string being built into a tainted allocation if it meets a %s for a
65 tainted argument. Any intermediate-layer function that (can) return a new
66 allocation should behave this way; returning a tainted result if any tainted
67 content is used. Intermediate-layer functions (eg. Ustrncpy) that modify
68 existing allocations fail if tainted data is written into an untainted area.
69 Users of functions that modify existing allocations should check if a tainted
70 source and an untainted destination is used, and fail instead (sprintf() being
76 /* keep config.h before memcheck.h, for NVALGRIND */
83 /* We need to know how to align blocks of data for general use. I'm not sure
84 how to get an alignment factor in general. In the current world, a value of 8
85 is probably right, and this is sizeof(double) on some systems and sizeof(void
86 *) on others, so take the larger of those. Since everything in this expression
87 is a constant, the compiler should optimize it to a simple constant wherever it
88 appears (I checked that gcc does do this). */
91 (sizeof(void *) > sizeof(double) ? sizeof(void *) : sizeof(double))
93 /* store_reset() will not free the following block if the last used block has
94 less than this much left in it. */
96 #define STOREPOOL_MIN_SIZE 256
98 /* Structure describing the beginning of each big block. */
100 typedef struct storeblock {
101 struct storeblock *next;
105 /* Pool descriptor struct */
107 typedef struct pooldesc {
108 storeblock * chainbase; /* list of blocks in pool */
109 storeblock * current_block; /* top block, still with free space */
110 void * next_yield; /* next allocation point */
111 int yield_length; /* remaining space in current block */
112 unsigned store_block_order; /* log2(size) block allocation size */
114 /* This variable is set by store_get() to its yield, and by store_reset() to
115 NULL. This enables string_cat() to optimize its store handling for very long
116 strings. That's why the variable is global. */
118 void * store_last_get;
120 /* These are purely for stats-gathering */
129 /* Enhanced pool descriptor for quoted pools */
131 typedef struct quoted_pooldesc {
134 struct quoted_pooldesc * next;
137 /* Just in case we find ourselves on a system where the structure above has a
138 length that is not a multiple of the alignment, set up a macro for the padded
141 #define ALIGNED_SIZEOF_STOREBLOCK \
142 (((sizeof(storeblock) + alignment - 1) / alignment) * alignment)
144 /* Size of block to get from malloc to carve up into smaller ones. This
145 must be a multiple of the alignment. We assume that 4096 is going to be
146 suitably aligned. Double the size per-pool for every malloc, to mitigate
147 certain denial-of-service attacks. Don't bother to decrease on block frees.
148 We waste average half the current alloc size per pool. This could be several
149 hundred kB now, vs. 4kB with a constant-size block size. But the search time
150 for is_tainted(), linear in the number of blocks for the pool, is O(n log n)
152 A test of 2000 RCPTs and just accept ACL had 370kB in 21 blocks before,
153 504kB in 6 blocks now, for the untainted-main (largest) pool.
154 Builds for restricted-memory system can disable the expansion by
155 defining RESTRICTED_MEMORY */
156 /*XXX should we allow any for malloc's own overhead? But how much? */
158 /* #define RESTRICTED_MEMORY */
159 #define STORE_BLOCK_SIZE(order) ((1U << (order)) - ALIGNED_SIZEOF_STOREBLOCK)
161 /* Variables holding data for the local pools of store. The current pool number
162 is held in store_pool, which is global so that it can be changed from outside.
163 Setting the initial length values to -1 forces a malloc for the first call,
164 even if the length is zero (which is used for getting a point to reset to). */
166 int store_pool = POOL_MAIN;
168 pooldesc paired_pools[N_PAIRED_POOLS];
169 quoted_pooldesc * quoted_pools = NULL;
171 static int n_nonpool_blocks; /* current number of direct store_malloc() blocks */
172 static int max_nonpool_blocks;
173 static int max_pool_malloc; /* max value for pool_malloc */
174 static int max_nonpool_malloc; /* max value for nonpool_malloc */
176 /* pool_malloc holds the amount of memory used by the store pools; this goes up
177 and down as store is reset or released. nonpool_malloc is the total got by
178 malloc from other calls; this doesn't go down because it is just freed by
181 static int pool_malloc;
182 static int nonpool_malloc;
185 #ifndef COMPILE_UTILITY
186 static const uschar * pooluse[N_PAIRED_POOLS] = {
187 [POOL_MAIN] = US"main",
188 [POOL_PERM] = US"perm",
189 [POOL_CONFIG] = US"config",
190 [POOL_SEARCH] = US"search",
191 [POOL_MESSAGE] = US"message",
192 [POOL_TAINT_MAIN] = US"main",
193 [POOL_TAINT_PERM] = US"perm",
194 [POOL_TAINT_CONFIG] = US"config",
195 [POOL_TAINT_SEARCH] = US"search",
196 [POOL_TAINT_MESSAGE] = US"message",
198 static const uschar * poolclass[N_PAIRED_POOLS] = {
199 [POOL_MAIN] = US"untainted",
200 [POOL_PERM] = US"untainted",
201 [POOL_CONFIG] = US"untainted",
202 [POOL_SEARCH] = US"untainted",
203 [POOL_MESSAGE] = US"untainted",
204 [POOL_TAINT_MAIN] = US"tainted",
205 [POOL_TAINT_PERM] = US"tainted",
206 [POOL_TAINT_CONFIG] = US"tainted",
207 [POOL_TAINT_SEARCH] = US"tainted",
208 [POOL_TAINT_MESSAGE] = US"tainted",
213 static void * internal_store_malloc(size_t, const char *, int);
214 static void internal_store_free(void *, const char *, int linenumber);
216 /******************************************************************************/
219 pool_init(pooldesc * pp)
221 memset(pp, 0, sizeof(*pp));
222 pp->yield_length = -1;
223 pp->store_block_order = 12; /* log2(allocation_size) ie. 4kB */
226 /* Initialisation, for things fragile with parameter channges when using
227 static initialisers. */
232 for (pooldesc * pp = paired_pools; pp < paired_pools + N_PAIRED_POOLS; pp++)
236 /******************************************************************************/
237 /* Locating elements given memory pointer */
240 is_pointer_in_block(const storeblock * b, const void * p)
242 uschar * bc = US b + ALIGNED_SIZEOF_STOREBLOCK;
243 return US p >= bc && US p < bc + b->length;
247 pool_current_for_pointer(const void * p)
251 for (quoted_pooldesc * qp = quoted_pools; qp; qp = qp->next)
252 if ((b = qp->pool.current_block) && is_pointer_in_block(b, p))
255 for (pooldesc * pp = paired_pools; pp < paired_pools + N_PAIRED_POOLS; pp++)
256 if ((b = pp->current_block) && is_pointer_in_block(b, p))
262 pool_for_pointer(const void * p)
267 if ((pp = pool_current_for_pointer(p))) return pp;
269 for (quoted_pooldesc * qp = quoted_pools; qp; qp = qp->next)
270 for (b = qp->pool.chainbase; b; b = b->next)
271 if (is_pointer_in_block(b, p)) return &qp->pool;
273 for (pp = paired_pools; pp < paired_pools + N_PAIRED_POOLS; pp++)
274 for (b = pp->chainbase; b; b = b->next)
275 if (is_pointer_in_block(b, p)) return pp;
277 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "bad memory reference; pool not found");
281 /******************************************************************************/
282 /* Test if a pointer refers to tainted memory.
284 Slower version check, for use when platform intermixes malloc and mmap area
285 addresses. Test against the current-block of all tainted pools first, then all
286 blocks of all tainted pools.
288 Return: TRUE iff tainted
292 is_tainted_fn(const void * p)
296 if (p == GET_UNTAINTED) return FALSE;
297 if (p == GET_TAINTED) return TRUE;
299 for (pooldesc * pp = paired_pools + POOL_TAINT_BASE;
300 pp < paired_pools + N_PAIRED_POOLS; pp++)
301 if ((b = pp->current_block))
302 if (is_pointer_in_block(b, p)) return TRUE;
304 for (quoted_pooldesc * qp = quoted_pools; qp; qp = qp->next)
305 if (b = qp->pool.current_block)
306 if (is_pointer_in_block(b, p)) return TRUE;
308 for (pooldesc * pp = paired_pools + POOL_TAINT_BASE;
309 pp < paired_pools + N_PAIRED_POOLS; pp++)
310 for (b = pp->chainbase; b; b = b->next)
311 if (is_pointer_in_block(b, p)) return TRUE;
313 for (quoted_pooldesc * qp = quoted_pools; qp; qp = qp->next)
314 for (b = qp->pool.chainbase; b; b = b->next)
315 if (is_pointer_in_block(b, p)) return TRUE;
322 die_tainted(const uschar * msg, const uschar * func, int line)
324 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Taint mismatch, %s: %s %d\n",
329 #ifndef COMPILE_UTILITY
330 /* Return the pool for the given quoter, or null */
333 pool_for_quoter(unsigned quoter)
335 for (quoted_pooldesc * qp = quoted_pools; qp; qp = qp->next)
336 if (qp->quoter == quoter)
341 /* Allocate/init a new quoted-pool and return the pool */
344 quoted_pool_new(unsigned quoter)
346 // debug_printf("allocating quoted-pool\n");
347 quoted_pooldesc * qp = store_get_perm(sizeof(quoted_pooldesc), GET_UNTAINTED);
349 pool_init(&qp->pool);
351 qp->next = quoted_pools;
358 /******************************************************************************/
360 store_writeprotect(int pool)
362 #if !defined(COMPILE_UTILITY) && !defined(MISSING_POSIX_MEMALIGN)
363 for (storeblock * b = paired_pools[pool].chainbase; b; b = b->next)
364 if (mprotect(b, ALIGNED_SIZEOF_STOREBLOCK + b->length, PROT_READ) != 0)
365 DEBUG(D_any) debug_printf("config block mprotect: (%d) %s\n", errno, strerror(errno));
369 /******************************************************************************/
372 pool_get(pooldesc * pp, int size, BOOL align_mem, const char * func, int linenumber)
374 /* Ensure we've been asked to allocate memory.
375 A negative size is a sign of a security problem.
376 A zero size might be also suspect, but our internal usage deliberately
377 does this to return a current watermark value for a later release of
380 if (size < 0 || size >= INT_MAX/2)
381 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
382 "bad memory allocation requested (%d bytes) at %s %d",
383 size, func, linenumber);
385 /* Round up the size to a multiple of the alignment. Although this looks a
386 messy statement, because "alignment" is a constant expression, the compiler can
387 do a reasonable job of optimizing, especially if the value of "alignment" is a
388 power of two. I checked this with -O2, and gcc did very well, compiling it to 4
389 instructions on a Sparc (alignment = 8). */
391 if (size % alignment != 0) size += alignment - (size % alignment);
393 /* If there isn't room in the current block, get a new one. The minimum
394 size is STORE_BLOCK_SIZE, and we would expect this to be the norm, since
395 these functions are mostly called for small amounts of store. */
397 if (size > pp->yield_length)
400 STORE_BLOCK_SIZE(pp->store_block_order) - ALIGNED_SIZEOF_STOREBLOCK,
402 int mlength = length + ALIGNED_SIZEOF_STOREBLOCK;
403 storeblock * newblock;
405 /* Sometimes store_reset() may leave a block for us; check if we can use it */
407 if ( (newblock = pp->current_block)
408 && (newblock = newblock->next)
409 && newblock->length < length
412 /* Give up on this block, because it's too small */
414 internal_store_free(newblock, func, linenumber);
418 /* If there was no free block, get a new one */
422 if ((pp->nbytes += mlength) > pp->maxbytes)
423 pp->maxbytes = pp->nbytes;
424 if ((pool_malloc += mlength) > max_pool_malloc) /* Used in pools */
425 max_pool_malloc = pool_malloc;
426 nonpool_malloc -= mlength; /* Exclude from overall total */
427 if (++pp->nblocks > pp->maxblocks)
428 pp->maxblocks = pp->nblocks;
430 #ifndef MISSING_POSIX_MEMALIGN
433 long pgsize = sysconf(_SC_PAGESIZE);
434 int err = posix_memalign((void **)&newblock,
435 pgsize, (mlength + pgsize - 1) & ~(pgsize - 1));
437 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
438 "failed to alloc (using posix_memalign) %d bytes of memory: '%s'"
439 "called from line %d in %s",
440 size, strerror(err), linenumber, func);
444 newblock = internal_store_malloc(mlength, func, linenumber);
445 newblock->next = NULL;
446 newblock->length = length;
447 #ifndef RESTRICTED_MEMORY
448 if (pp->store_block_order++ > pp->maxorder)
449 pp->maxorder = pp->store_block_order;
453 pp->chainbase = newblock;
455 pp->current_block->next = newblock;
458 pp->current_block = newblock;
459 pp->yield_length = newblock->length;
461 (void *)(CS pp->current_block + ALIGNED_SIZEOF_STOREBLOCK);
462 (void) VALGRIND_MAKE_MEM_NOACCESS(pp->next_yield, pp->yield_length);
465 /* There's (now) enough room in the current block; the yield is the next
468 pp->store_last_get = pp->next_yield;
470 (void) VALGRIND_MAKE_MEM_UNDEFINED(pp->store_last_get, size);
471 /* Update next pointer and number of bytes left in the current block. */
473 pp->next_yield = (void *)(CS pp->next_yield + size);
474 pp->yield_length -= size;
475 return pp->store_last_get;
478 /*************************************************
479 * Get a block from the current pool *
480 *************************************************/
482 /* Running out of store is a total disaster. This function is called via the
483 macro store_get(). The current store_pool is used, adjusting for taint.
484 If the protoype is quoted, use a quoted-pool.
485 Return a block of store within the current big block of the pool, getting a new
486 one if necessary. The address is saved in store_last_get for the pool.
489 size amount wanted, bytes
490 proto_mem class: get store conformant to this
491 Special values: 0 forces untainted, 1 forces tainted
492 func function from which called
493 linenumber line number in source file
495 Returns: pointer to store (panic on malloc failure)
499 store_get_3(int size, const void * proto_mem, const char * func, int linenumber)
501 #ifndef COMPILE_UTILITY
502 int quoter = quoter_for_address(proto_mem);
507 #ifndef COMPILE_UTILITY
508 if (!is_real_quoter(quoter))
511 BOOL tainted = is_tainted(proto_mem);
512 int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool;
513 pp = paired_pools + pool;
514 yield = pool_get(pp, size, (pool == POOL_CONFIG), func, linenumber);
516 /* Cut out the debugging stuff for utilities, but stop picky compilers from
519 #ifndef COMPILE_UTILITY
521 debug_printf("---%d Get %6p %5d %-14s %4d\n", pool,
522 pp->store_last_get, size, func, linenumber);
525 #ifndef COMPILE_UTILITY
529 debug_printf("allocating quoted-block for quoter %u (from %s %d)\n",
530 quoter, func, linenumber);
531 if (!(pp = pool_for_quoter(quoter))) pp = quoted_pool_new(quoter);
532 yield = pool_get(pp, size, FALSE, func, linenumber);
534 debug_printf("---QQ Get %6p %5d %-14s %4d\n",
535 pp->store_last_get, size, func, linenumber);
543 /*************************************************
544 * Get a block from the PERM pool *
545 *************************************************/
547 /* This is just a convenience function, useful when just a single block is to
552 proto_mem class: get store conformant to this
553 func function from which called
554 linenumber line number in source file
556 Returns: pointer to store (panic on malloc failure)
560 store_get_perm_3(int size, const void * proto_mem, const char * func, int linenumber)
563 int old_pool = store_pool;
564 store_pool = POOL_PERM;
565 yield = store_get_3(size, proto_mem, func, linenumber);
566 store_pool = old_pool;
571 #ifndef COMPILE_UTILITY
572 /*************************************************
573 * Get a block annotated as being lookup-quoted *
574 *************************************************/
576 /* Allocate from pool a pool consistent with the proto_mem augmented by the
577 requested quoter type.
579 XXX currently not handling mark/release
581 Args: size number of bytes to allocate
582 quoter id for the quoting type
583 func caller, for debug
584 linenumber caller, for debug
586 Return: allocated memory block
590 store_force_get_quoted(int size, unsigned quoter,
591 const char * func, int linenumber)
593 pooldesc * pp = pool_for_quoter(quoter);
597 debug_printf("allocating quoted-block for quoter %u (from %s %d)\n", quoter, func, linenumber);
599 if (!pp) pp = quoted_pool_new(quoter);
600 yield = pool_get(pp, size, FALSE, func, linenumber);
603 debug_printf("---QQ Get %6p %5d %-14s %4d\n",
604 pp->store_last_get, size, func, linenumber);
609 /* Maybe get memory for the specified quoter, but only if the
610 prototype memory is tainted. Otherwise, get plain memory.
613 store_get_quoted_3(int size, const void * proto_mem, unsigned quoter,
614 const char * func, int linenumber)
616 // debug_printf("store_get_quoted_3: quoter %u\n", quoter);
617 return is_tainted(proto_mem)
618 ? store_force_get_quoted(size, quoter, func, linenumber)
619 : store_get_3(size, proto_mem, func, linenumber);
622 /* Return quoter for given address, or -1 if not in a quoted-pool. */
624 quoter_for_address(const void * p)
626 for (quoted_pooldesc * qp = quoted_pools; qp; qp = qp->next)
628 pooldesc * pp = &qp->pool;
631 if (b = pp->current_block)
632 if (is_pointer_in_block(b, p))
635 for (b = pp->chainbase; b; b = b->next)
636 if (is_pointer_in_block(b, p))
642 /* Return TRUE iff the given address is quoted for the given type.
643 There is extra complexity to handle lookup providers with multiple
644 find variants but shared quote functions. */
646 is_quoted_like(const void * p, unsigned quoter)
648 int pq = quoter_for_address(p);
650 is_real_quoter(pq) && lookup_list[pq]->quote == lookup_list[quoter]->quote;
651 /* debug_printf("is_quoted(%p, %u): %c\n", p, quoter, y?'T':'F'); */
655 /* Return TRUE if the quoter value indicates an actual quoter */
657 is_real_quoter(int quoter)
662 /* Return TRUE if the "new" data requires that the "old" data
663 be recopied to new-class memory. We order the classes as
665 2: tainted, not quoted
666 1: quoted (which is also tainted)
669 If the "new" is higher-order than the "old", they are not compatible
670 and a copy is needed. If both are quoted, but the quoters differ,
671 not compatible. Otherwise they are compatible.
674 is_incompatible_fn(const void * old, const void * new)
679 ni = is_real_quoter(nq = quoter_for_address(new)) ? 1 : is_tainted(new) ? 2 : 0;
680 oi = is_real_quoter(oq = quoter_for_address(old)) ? 1 : is_tainted(old) ? 2 : 0;
681 return ni > oi || ni == oi && nq != oq;
684 #endif /*!COMPILE_UTILITY*/
686 /*************************************************
687 * Extend a block if it is at the top *
688 *************************************************/
690 /* While reading strings of unknown length, it is often the case that the
691 string is being read into the block at the top of the stack. If it needs to be
692 extended, it is more efficient just to extend within the top block rather than
693 allocate a new block and then have to copy the data. This function is provided
694 for the use of string_cat(), but of course can be used elsewhere too.
695 The block itself is not expanded; only the top allocation from it.
698 ptr pointer to store block
699 oldsize current size of the block, as requested by user
700 newsize new size required
701 func function from which called
702 linenumber line number in source file
704 Returns: TRUE if the block is at the top of the stack and has been
705 extended; FALSE if it isn't at the top of the stack, or cannot
708 XXX needs extension for quoted-tracking. This assumes that the global store_pool
709 is the one to alloc from, which breaks with separated pools.
713 store_extend_3(void * ptr, int oldsize, int newsize,
714 const char * func, int linenumber)
716 pooldesc * pp = pool_for_pointer(ptr);
717 int inc = newsize - oldsize;
718 int rounded_oldsize = oldsize;
720 if (oldsize < 0 || newsize < oldsize || newsize >= INT_MAX/2)
721 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
722 "bad memory extension requested (%d -> %d bytes) at %s %d",
723 oldsize, newsize, func, linenumber);
725 if (rounded_oldsize % alignment != 0)
726 rounded_oldsize += alignment - (rounded_oldsize % alignment);
728 if (CS ptr + rounded_oldsize != CS (pp->next_yield) ||
729 inc > pp->yield_length + rounded_oldsize - oldsize)
732 /* Cut out the debugging stuff for utilities, but stop picky compilers from
735 #ifndef COMPILE_UTILITY
738 quoted_pooldesc * qp;
739 for (qp = quoted_pools; qp; qp = qp->next)
742 debug_printf("---Q%d Ext %6p %5d %-14s %4d\n",
743 (int)(qp - quoted_pools),
744 ptr, newsize, func, linenumber);
748 debug_printf("---%d Ext %6p %5d %-14s %4d\n",
749 (int)(pp - paired_pools),
750 ptr, newsize, func, linenumber);
752 #endif /* COMPILE_UTILITY */
754 if (newsize % alignment != 0) newsize += alignment - (newsize % alignment);
755 pp->next_yield = CS ptr + newsize;
756 pp->yield_length -= newsize - rounded_oldsize;
757 (void) VALGRIND_MAKE_MEM_UNDEFINED(ptr + oldsize, inc);
765 is_pwr2_size(int len)
768 return (x & (x - 1)) == 0;
772 /*************************************************
773 * Back up to a previous point on the stack *
774 *************************************************/
776 /* This function resets the next pointer, freeing any subsequent whole blocks
777 that are now unused. Call with a cookie obtained from store_mark() only; do
778 not call with a pointer returned by store_get(). Both the untainted and tainted
779 pools corresposding to store_pool are reset.
781 Quoted pools are not handled.
784 ptr place to back up to
785 pool pool holding the pointer
786 func function from which called
787 linenumber line number in source file
793 internal_store_reset(void * ptr, int pool, const char *func, int linenumber)
796 pooldesc * pp = paired_pools + pool;
797 storeblock * b = pp->current_block;
798 char * bc = CS b + ALIGNED_SIZEOF_STOREBLOCK;
799 int newlength, count;
800 #ifndef COMPILE_UTILITY
801 int oldmalloc = pool_malloc;
804 if (!b) return; /* exim_dumpdb gets this, becuse it has never used tainted mem */
806 /* Last store operation was not a get */
808 pp->store_last_get = NULL;
810 /* See if the place is in the current block - as it often will be. Otherwise,
811 search for the block in which it lies. */
813 if (CS ptr < bc || CS ptr > bc + b->length)
815 for (b = pp->chainbase; b; b = b->next)
817 bc = CS b + ALIGNED_SIZEOF_STOREBLOCK;
818 if (CS ptr >= bc && CS ptr <= bc + b->length) break;
821 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal error: store_reset(%p) "
822 "failed: pool=%d %-14s %4d", ptr, pool, func, linenumber);
825 /* Back up, rounding to the alignment if necessary. When testing, flatten
826 the released memory. */
828 newlength = bc + b->length - CS ptr;
829 #ifndef COMPILE_UTILITY
832 assert_no_variables(ptr, newlength, func, linenumber);
833 if (f.running_in_test_harness)
835 (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength);
836 memset(ptr, 0xF0, newlength);
840 (void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength);
841 pp->next_yield = CS ptr + (newlength % alignment);
842 count = pp->yield_length;
843 count = (pp->yield_length = newlength - (newlength % alignment)) - count;
844 pp->current_block = b;
846 /* Free any subsequent block. Do NOT free the first
847 successor, if our current block has less than 256 bytes left. This should
848 prevent us from flapping memory. However, keep this block only when it has
849 a power-of-two size so probably is not a custom inflated one. */
851 if ( pp->yield_length < STOREPOOL_MIN_SIZE
853 && is_pwr2_size(b->next->length + ALIGNED_SIZEOF_STOREBLOCK))
856 #ifndef COMPILE_UTILITY
858 assert_no_variables(b, b->length + ALIGNED_SIZEOF_STOREBLOCK,
861 (void) VALGRIND_MAKE_MEM_NOACCESS(CS b + ALIGNED_SIZEOF_STOREBLOCK,
862 b->length - ALIGNED_SIZEOF_STOREBLOCK);
866 if (pool != POOL_CONFIG)
871 int siz = b->length + ALIGNED_SIZEOF_STOREBLOCK;
873 #ifndef COMPILE_UTILITY
875 assert_no_variables(b, b->length + ALIGNED_SIZEOF_STOREBLOCK,
882 if (pool != POOL_CONFIG)
883 internal_store_free(b, func, linenumber);
885 #ifndef RESTRICTED_MEMORY
886 if (pp->store_block_order > 13) pp->store_block_order--;
890 /* Cut out the debugging stuff for utilities, but stop picky compilers from
893 #ifndef COMPILE_UTILITY
895 debug_printf("---%d Rst %6p %5d %-14s %4d\tpool %d\n", pool, ptr,
896 count + oldmalloc - pool_malloc,
897 func, linenumber, pool_malloc);
898 #endif /* COMPILE_UTILITY */
902 /* Back up the pool pair, untainted and tainted, of the store_pool setting.
903 Quoted pools are not handled.
907 store_reset_3(rmark r, const char * func, int linenumber)
911 if (store_pool >= POOL_TAINT_BASE)
912 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
913 "store_reset called for pool %d: %s %d\n", store_pool, func, linenumber);
915 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
916 "store_reset called with bad mark: %s %d\n", func, linenumber);
918 internal_store_reset(*ptr, store_pool + POOL_TAINT_BASE, func, linenumber);
919 internal_store_reset(ptr, store_pool, func, linenumber);
926 /* Free tail-end unused allocation. This lets us allocate a big chunk
927 early, for cases when we only discover later how much was really needed.
929 Can be called with a value from store_get(), or an offset after such. Only
930 the tainted or untainted pool that serviced the store_get() will be affected.
932 This is mostly a cut-down version of internal_store_reset().
933 XXX needs rationalising
937 store_release_above_3(void * ptr, const char * func, int linenumber)
941 /* Search all pools' "current" blocks. If it isn't one of those,
942 ignore it (it usually will be). */
944 if ((pp = pool_current_for_pointer(ptr)))
946 storeblock * b = pp->current_block;
947 int count, newlength;
949 /* Last store operation was not a get */
951 pp->store_last_get = NULL;
953 /* Back up, rounding to the alignment if necessary. When testing, flatten
954 the released memory. */
956 newlength = (CS b + ALIGNED_SIZEOF_STOREBLOCK) + b->length - CS ptr;
957 #ifndef COMPILE_UTILITY
960 assert_no_variables(ptr, newlength, func, linenumber);
961 if (f.running_in_test_harness)
963 (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength);
964 memset(ptr, 0xF0, newlength);
968 (void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength);
969 pp->next_yield = CS ptr + (newlength % alignment);
970 count = pp->yield_length;
971 count = (pp->yield_length = newlength - (newlength % alignment)) - count;
973 /* Cut out the debugging stuff for utilities, but stop picky compilers from
976 #ifndef COMPILE_UTILITY
979 quoted_pooldesc * qp;
980 for (qp = quoted_pools; qp; qp = qp->next)
982 debug_printf("---Q%d Rel %6p %5d %-14s %4d\tpool %d\n",
983 (int)(qp - quoted_pools),
984 ptr, count, func, linenumber, pool_malloc);
986 debug_printf("---%d Rel %6p %5d %-14s %4d\tpool %d\n",
987 (int)(pp - paired_pools), ptr, count,
988 func, linenumber, pool_malloc);
993 #ifndef COMPILE_UTILITY
995 debug_printf("non-last memory release try: %s %d\n", func, linenumber);
1002 store_mark_3(const char * func, int linenumber)
1006 #ifndef COMPILE_UTILITY
1008 debug_printf("---%d Mrk %-14s %4d\tpool %d\n",
1009 store_pool, func, linenumber, pool_malloc);
1010 #endif /* COMPILE_UTILITY */
1012 if (store_pool >= POOL_TAINT_BASE)
1013 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
1014 "store_mark called for pool %d: %s %d\n", store_pool, func, linenumber);
1016 /* Stash a mark for the tainted-twin release, in the untainted twin. Return
1017 a cookie (actually the address in the untainted pool) to the caller.
1018 Reset uses the cookie to recover the t-mark, winds back the tainted pool with it
1019 and winds back the untainted pool with the cookie. */
1021 p = store_get_3(sizeof(void *), GET_UNTAINTED, func, linenumber);
1022 *p = store_get_3(0, GET_TAINTED, func, linenumber);
1029 /************************************************
1031 ************************************************/
1033 /* This function checks that the pointer it is given is the first thing in a
1034 block, and if so, releases that block.
1037 block block of store to consider
1038 pp pool containing the block
1039 func function from which called
1040 linenumber line number in source file
1046 store_release_3(void * block, pooldesc * pp, const char * func, int linenumber)
1048 /* It will never be the first block, so no need to check that. */
1050 for (storeblock * b = pp->chainbase; b; b = b->next)
1052 storeblock * bb = b->next;
1053 if (bb && CS block == CS bb + ALIGNED_SIZEOF_STOREBLOCK)
1055 int siz = bb->length + ALIGNED_SIZEOF_STOREBLOCK;
1061 /* Cut out the debugging stuff for utilities, but stop picky compilers
1062 from giving warnings. */
1064 #ifndef COMPILE_UTILITY
1066 debug_printf("-Release %6p %-20s %4d %d\n", (void *)bb, func,
1067 linenumber, pool_malloc);
1069 if (f.running_in_test_harness)
1070 memset(bb, 0xF0, bb->length+ALIGNED_SIZEOF_STOREBLOCK);
1071 #endif /* COMPILE_UTILITY */
1073 internal_store_free(bb, func, linenumber);
1080 /************************************************
1082 ************************************************/
1084 /* Allocate a new block big enough to expend to the given size and
1085 copy the current data into it. Free the old one if possible.
1087 This function is specifically provided for use when reading very
1088 long strings, e.g. header lines. When the string gets longer than a
1089 complete block, it gets copied to a new block. It is helpful to free
1090 the old block iff the previous copy of the string is at its start,
1091 and therefore the only thing in it. Otherwise, for very long strings,
1092 dead store can pile up somewhat disastrously. This function checks that
1093 the pointer it is given is the first thing in a block, and that nothing
1094 has been allocated since. If so, releases that block.
1098 newsize requested size
1101 Returns: new location of data
1105 store_newblock_3(void * oldblock, int newsize, int len,
1106 const char * func, int linenumber)
1108 pooldesc * pp = pool_for_pointer(oldblock);
1109 BOOL release_ok = !is_tainted(oldblock) && pp->store_last_get == oldblock; /*XXX why tainted not handled? */
1112 if (len < 0 || len > newsize)
1113 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
1114 "bad memory extension requested (%d -> %d bytes) at %s %d",
1115 len, newsize, func, linenumber);
1117 newblock = store_get(newsize, oldblock);
1118 memcpy(newblock, oldblock, len);
1119 if (release_ok) store_release_3(oldblock, pp, func, linenumber);
1120 return (void *)newblock;
1126 /*************************************************
1128 *************************************************/
1130 /* Running out of store is a total disaster for exim. Some malloc functions
1131 do not run happily on very small sizes, nor do they document this fact. This
1132 function is called via the macro store_malloc().
1135 size amount of store wanted
1136 func function from which called
1137 line line number in source file
1139 Returns: pointer to gotten store (panic on failure)
1143 internal_store_malloc(size_t size, const char *func, int line)
1147 /* Check specifically for a possibly result of conversion from
1148 a negative int, to the (unsigned, wider) size_t */
1150 if (size >= INT_MAX/2)
1151 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
1152 "bad memory allocation requested (" SIZE_T_FMT " bytes) at %s %d",
1155 size += sizeof(size_t); /* space to store the size, used under debug */
1156 if (size < 16) size = 16;
1158 if (!(yield = malloc(size)))
1159 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to malloc " SIZE_T_FMT " bytes of memory: "
1160 "called from line %d in %s", size, line, func);
1162 #ifndef COMPILE_UTILITY
1163 DEBUG(D_any) *(size_t *)yield = size;
1165 yield = US yield + sizeof(size_t);
1167 if ((nonpool_malloc += size) > max_nonpool_malloc)
1168 max_nonpool_malloc = nonpool_malloc;
1170 /* Cut out the debugging stuff for utilities, but stop picky compilers from
1173 #ifndef COMPILE_UTILITY
1174 /* If running in test harness, spend time making sure all the new store
1175 is not filled with zeros so as to catch problems. */
1177 if (f.running_in_test_harness)
1178 memset(yield, 0xF0, size - sizeof(size_t));
1179 DEBUG(D_memory) debug_printf("--Malloc %6p %5lu bytes\t%-20s %4d\tpool %5d nonpool %5d\n",
1180 yield, size, func, line, pool_malloc, nonpool_malloc);
1181 #endif /* COMPILE_UTILITY */
1187 store_malloc_3(size_t size, const char *func, int linenumber)
1189 if (n_nonpool_blocks++ > max_nonpool_blocks)
1190 max_nonpool_blocks = n_nonpool_blocks;
1191 return internal_store_malloc(size, func, linenumber);
1195 /************************************************
1197 ************************************************/
1199 /* This function is called by the macro store_free().
1202 block block of store to free
1203 func function from which called
1204 linenumber line number in source file
1210 internal_store_free(void * block, const char * func, int linenumber)
1212 uschar * p = US block - sizeof(size_t);
1213 #ifndef COMPILE_UTILITY
1214 DEBUG(D_any) nonpool_malloc -= *(size_t *)p;
1215 DEBUG(D_memory) debug_printf("----Free %6p %5ld bytes\t%-20s %4d\n",
1216 block, *(size_t *)p, func, linenumber);
1222 store_free_3(void * block, const char * func, int linenumber)
1225 internal_store_free(block, func, linenumber);
1228 /******************************************************************************/
1229 /* Stats output on process exit */
1233 #ifndef COMPILE_UTILITY
1237 debug_printf("----Exit nonpool max: %3d kB in %d blocks\n",
1238 (max_nonpool_malloc+1023)/1024, max_nonpool_blocks);
1239 debug_printf("----Exit npools max: %3d kB\n", max_pool_malloc/1024);
1241 for (i = 0; i < N_PAIRED_POOLS; i++)
1243 pooldesc * pp = paired_pools + i;
1244 debug_printf("----Exit pool %2d max: %3d kB in %d blocks at order %u\t%s %s\n",
1245 i, (pp->maxbytes+1023)/1024, pp->maxblocks, pp->maxorder,
1246 poolclass[i], pooluse[i]);
1249 for (quoted_pooldesc * qp = quoted_pools; qp; i++, qp = qp->next)
1251 pooldesc * pp = &qp->pool;
1252 debug_printf("----Exit pool Q%d max: %3d kB in %d blocks at order %u\ttainted quoted:%s\n",
1253 i, (pp->maxbytes+1023)/1024, pp->maxblocks, pp->maxorder, lookup_list[qp->quoter]->name);
1260 /******************************************************************************/
1261 /* Per-message pool management */
1263 static rmark message_reset_point = NULL;
1268 int oldpool = store_pool;
1269 store_pool = POOL_MESSAGE;
1270 if (!message_reset_point) message_reset_point = store_mark();
1271 store_pool = oldpool;
1275 message_tidyup(void)
1278 if (!message_reset_point) return;
1279 oldpool = store_pool;
1280 store_pool = POOL_MESSAGE;
1281 message_reset_point = store_reset(message_reset_point);
1282 store_pool = oldpool;
1285 /******************************************************************************/
1286 /* Debug analysis of address */
1288 #ifndef COMPILE_UTILITY
1290 debug_print_taint(const void * p)
1292 int q = quoter_for_address(p);
1293 if (!is_tainted(p)) return;
1294 debug_printf("(tainted");
1295 if (is_real_quoter(q)) debug_printf(", quoted:%s", lookup_list[q]->name);
1296 debug_printf(")\n");
1300 /* End of store.c */