1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim maintainers 2019 - 2020 */
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 . Orthogonal to the three pool types, there are two classes of memory: untainted
48 and tainted. The latter is used for values derived from untrusted input, and
49 the string-expansion mechanism refuses to operate on such values (obviously,
50 it can expand an untainted value to return a tainted result). The classes
51 are implemented by duplicating the four pool types. Pool resets are requested
52 against the nontainted sibling and apply to both siblings.
54 Only memory blocks requested for tainted use are regarded as tainted; anything
55 else (including stack auto variables) is untainted. Care is needed when coding
56 to not copy untrusted data into untainted memory, as downstream taint-checks
59 Intermediate layers (eg. the string functions) can test for taint, and use this
60 for ensurinng that results have proper state. For example the
61 string_vformat_trc() routing supporting the string_sprintf() interface will
62 recopy a string being built into a tainted allocation if it meets a %s for a
63 tainted argument. Any intermediate-layer function that (can) return a new
64 allocation should behave this way; returning a tainted result if any tainted
65 content is used. Intermediate-layer functions (eg. Ustrncpy) that modify
66 existing allocations fail if tainted data is written into an untainted area.
67 Users of functions that modify existing allocations should check if a tainted
68 source and an untainted destination is used, and fail instead (sprintf() being
74 /* keep config.h before memcheck.h, for NVALGRIND */
81 /* We need to know how to align blocks of data for general use. I'm not sure
82 how to get an alignment factor in general. In the current world, a value of 8
83 is probably right, and this is sizeof(double) on some systems and sizeof(void
84 *) on others, so take the larger of those. Since everything in this expression
85 is a constant, the compiler should optimize it to a simple constant wherever it
86 appears (I checked that gcc does do this). */
89 (sizeof(void *) > sizeof(double) ? sizeof(void *) : sizeof(double))
91 /* store_reset() will not free the following block if the last used block has
92 less than this much left in it. */
94 #define STOREPOOL_MIN_SIZE 256
96 /* Structure describing the beginning of each big block. */
98 typedef struct storeblock {
99 struct storeblock *next;
103 /* Just in case we find ourselves on a system where the structure above has a
104 length that is not a multiple of the alignment, set up a macro for the padded
107 #define ALIGNED_SIZEOF_STOREBLOCK \
108 (((sizeof(storeblock) + alignment - 1) / alignment) * alignment)
110 /* Size of block to get from malloc to carve up into smaller ones. This
111 must be a multiple of the alignment. We assume that 4096 is going to be
112 suitably aligned. Double the size per-pool for every malloc, to mitigate
113 certain denial-of-service attacks. Don't bother to decrease on block frees.
114 We waste average half the current alloc size per pool. This could be several
115 hundred kB now, vs. 4kB with a constant-size block size. But the search time
116 for is_tainted(), linear in the number of blocks for the pool, is O(n log n)
118 A test of 2000 RCPTs and just accept ACL had 370kB in 21 blocks before,
119 504kB in 6 blocks now, for the untainted-main (largest) pool.
120 Builds for restricted-memory system can disable the expansion by
121 defining RESTRICTED_MEMORY */
122 /*XXX should we allow any for malloc's own overhead? But how much? */
124 /* #define RESTRICTED_MEMORY */
125 #define STORE_BLOCK_SIZE(order) ((1U << (order)) - ALIGNED_SIZEOF_STOREBLOCK)
127 /* Variables holding data for the local pools of store. The current pool number
128 is held in store_pool, which is global so that it can be changed from outside.
129 Setting the initial length values to -1 forces a malloc for the first call,
130 even if the length is zero (which is used for getting a point to reset to). */
132 int store_pool = POOL_MAIN;
134 static storeblock *chainbase[NPOOLS];
135 static storeblock *current_block[NPOOLS];
136 static void *next_yield[NPOOLS];
137 static int yield_length[NPOOLS];
138 static unsigned store_block_order[NPOOLS];
140 /* pool_malloc holds the amount of memory used by the store pools; this goes up
141 and down as store is reset or released. nonpool_malloc is the total got by
142 malloc from other calls; this doesn't go down because it is just freed by
145 static int pool_malloc;
146 static int nonpool_malloc;
148 /* This variable is set by store_get() to its yield, and by store_reset() to
149 NULL. This enables string_cat() to optimize its store handling for very long
150 strings. That's why the variable is global. */
152 void *store_last_get[NPOOLS];
154 /* These are purely for stats-gathering */
156 static int nbytes[NPOOLS]; /* current bytes allocated */
157 static int maxbytes[NPOOLS]; /* max number reached */
158 static int nblocks[NPOOLS]; /* current number of blocks allocated */
159 static int maxblocks[NPOOLS];
160 static unsigned maxorder[NPOOLS];
161 static int n_nonpool_blocks; /* current number of direct store_malloc() blocks */
162 static int max_nonpool_blocks;
163 static int max_pool_malloc; /* max value for pool_malloc */
164 static int max_nonpool_malloc; /* max value for nonpool_malloc */
167 #ifndef COMPILE_UTILITY
168 static const uschar * pooluse[NPOOLS] = {
169 [POOL_MAIN] = US"main",
170 [POOL_PERM] = US"perm",
171 [POOL_CONFIG] = US"config",
172 [POOL_SEARCH] = US"search",
173 [POOL_MESSAGE] = US"message",
174 [POOL_TAINT_MAIN] = US"main",
175 [POOL_TAINT_PERM] = US"perm",
176 [POOL_TAINT_CONFIG] = US"config",
177 [POOL_TAINT_SEARCH] = US"search",
178 [POOL_TAINT_MESSAGE] = US"message",
180 static const uschar * poolclass[NPOOLS] = {
181 [POOL_MAIN] = US"untainted",
182 [POOL_PERM] = US"untainted",
183 [POOL_CONFIG] = US"untainted",
184 [POOL_SEARCH] = US"untainted",
185 [POOL_MESSAGE] = US"untainted",
186 [POOL_TAINT_MAIN] = US"tainted",
187 [POOL_TAINT_PERM] = US"tainted",
188 [POOL_TAINT_CONFIG] = US"tainted",
189 [POOL_TAINT_SEARCH] = US"tainted",
190 [POOL_TAINT_MESSAGE] = US"tainted",
195 static void * internal_store_malloc(int, const char *, int);
196 static void internal_store_free(void *, const char *, int linenumber);
198 /******************************************************************************/
199 /* Initialisation, for things fragile with parameter channges when using
200 static initialisers. */
205 for (int i = 0; i < NPOOLS; i++)
207 yield_length[i] = -1;
208 store_block_order[i] = 12; /* log2(allocation_size) ie. 4kB */
212 /******************************************************************************/
214 /* Test if a pointer refers to tainted memory.
216 Slower version check, for use when platform intermixes malloc and mmap area
217 addresses. Test against the current-block of all tainted pools first, then all
218 blocks of all tainted pools.
220 Return: TRUE iff tainted
224 is_tainted_fn(const void * p)
228 for (int pool = POOL_TAINT_BASE; pool < nelem(chainbase); pool++)
229 if ((b = current_block[pool]))
231 uschar * bc = US b + ALIGNED_SIZEOF_STOREBLOCK;
232 if (US p >= bc && US p < bc + b->length) return TRUE;
235 for (int pool = POOL_TAINT_BASE; pool < nelem(chainbase); pool++)
236 for (b = chainbase[pool]; b; b = b->next)
238 uschar * bc = US b + ALIGNED_SIZEOF_STOREBLOCK;
239 if (US p >= bc && US p < bc + b->length) return TRUE;
246 die_tainted(const uschar * msg, const uschar * func, int line)
248 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Taint mismatch, %s: %s %d\n",
254 /******************************************************************************/
256 store_writeprotect(int pool)
258 for (storeblock * b = chainbase[pool]; b; b = b->next)
260 #ifndef COMPILE_UTILITY
261 if (mprotect(b, ALIGNED_SIZEOF_STOREBLOCK + b->length, PROT_READ) != 0)
262 DEBUG(D_any) debug_printf("config block mprotect: (%d) %s\n", errno, strerror(errno))
268 /******************************************************************************/
270 /*************************************************
271 * Get a block from the current pool *
272 *************************************************/
274 /* Running out of store is a total disaster. This function is called via the
275 macro store_get(). It passes back a block of store within the current big
276 block, getting a new one if necessary. The address is saved in
280 size amount wanted, bytes
281 tainted class: set to true for untrusted data (eg. from smtp input)
282 func function from which called
283 linenumber line number in source file
285 Returns: pointer to store (panic on malloc failure)
289 store_get_3(int size, BOOL tainted, const char *func, int linenumber)
291 int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool;
293 /* Ensure we've been asked to allocate memory.
294 A negative size is a sign of a security problem.
295 A zero size might be also suspect, but our internal usage deliberately
296 does this to return a current watermark value for a later release of
299 if (size < 0 || size >= INT_MAX/2)
300 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
301 "bad memory allocation requested (%d bytes) at %s %d",
302 size, func, linenumber);
304 /* Round up the size to a multiple of the alignment. Although this looks a
305 messy statement, because "alignment" is a constant expression, the compiler can
306 do a reasonable job of optimizing, especially if the value of "alignment" is a
307 power of two. I checked this with -O2, and gcc did very well, compiling it to 4
308 instructions on a Sparc (alignment = 8). */
310 if (size % alignment != 0) size += alignment - (size % alignment);
312 /* If there isn't room in the current block, get a new one. The minimum
313 size is STORE_BLOCK_SIZE, and we would expect this to be the norm, since
314 these functions are mostly called for small amounts of store. */
316 if (size > yield_length[pool])
319 STORE_BLOCK_SIZE(store_block_order[pool]) - ALIGNED_SIZEOF_STOREBLOCK,
321 int mlength = length + ALIGNED_SIZEOF_STOREBLOCK;
322 storeblock * newblock;
324 /* Sometimes store_reset() may leave a block for us; check if we can use it */
326 if ( (newblock = current_block[pool])
327 && (newblock = newblock->next)
328 && newblock->length < length
331 /* Give up on this block, because it's too small */
333 internal_store_free(newblock, func, linenumber);
337 /* If there was no free block, get a new one */
341 if ((nbytes[pool] += mlength) > maxbytes[pool])
342 maxbytes[pool] = nbytes[pool];
343 if ((pool_malloc += mlength) > max_pool_malloc) /* Used in pools */
344 max_pool_malloc = pool_malloc;
345 nonpool_malloc -= mlength; /* Exclude from overall total */
346 if (++nblocks[pool] > maxblocks[pool])
347 maxblocks[pool] = nblocks[pool];
349 if (pool == POOL_CONFIG)
351 long pgsize = sysconf(_SC_PAGESIZE);
352 posix_memalign((void **)&newblock, pgsize, (mlength + pgsize - 1) & ~(pgsize - 1));
355 newblock = internal_store_malloc(mlength, func, linenumber);
356 newblock->next = NULL;
357 newblock->length = length;
358 #ifndef RESTRICTED_MEMORY
359 if (store_block_order[pool]++ > maxorder[pool])
360 maxorder[pool] = store_block_order[pool];
363 if (!chainbase[pool])
364 chainbase[pool] = newblock;
366 current_block[pool]->next = newblock;
369 current_block[pool] = newblock;
370 yield_length[pool] = newblock->length;
372 (void *)(CS current_block[pool] + ALIGNED_SIZEOF_STOREBLOCK);
373 (void) VALGRIND_MAKE_MEM_NOACCESS(next_yield[pool], yield_length[pool]);
376 /* There's (now) enough room in the current block; the yield is the next
379 store_last_get[pool] = next_yield[pool];
381 /* Cut out the debugging stuff for utilities, but stop picky compilers from
384 #ifndef COMPILE_UTILITY
386 debug_printf("---%d Get %6p %5d %-14s %4d\n", pool,
387 store_last_get[pool], size, func, linenumber);
388 #endif /* COMPILE_UTILITY */
390 (void) VALGRIND_MAKE_MEM_UNDEFINED(store_last_get[pool], size);
391 /* Update next pointer and number of bytes left in the current block. */
393 next_yield[pool] = (void *)(CS next_yield[pool] + size);
394 yield_length[pool] -= size;
395 return store_last_get[pool];
400 /*************************************************
401 * Get a block from the PERM pool *
402 *************************************************/
404 /* This is just a convenience function, useful when just a single block is to
409 func function from which called
410 linenumber line number in source file
412 Returns: pointer to store (panic on malloc failure)
416 store_get_perm_3(int size, BOOL tainted, const char *func, int linenumber)
419 int old_pool = store_pool;
420 store_pool = POOL_PERM;
421 yield = store_get_3(size, tainted, func, linenumber);
422 store_pool = old_pool;
428 /*************************************************
429 * Extend a block if it is at the top *
430 *************************************************/
432 /* While reading strings of unknown length, it is often the case that the
433 string is being read into the block at the top of the stack. If it needs to be
434 extended, it is more efficient just to extend within the top block rather than
435 allocate a new block and then have to copy the data. This function is provided
436 for the use of string_cat(), but of course can be used elsewhere too.
437 The block itself is not expanded; only the top allocation from it.
440 ptr pointer to store block
441 oldsize current size of the block, as requested by user
442 newsize new size required
443 func function from which called
444 linenumber line number in source file
446 Returns: TRUE if the block is at the top of the stack and has been
447 extended; FALSE if it isn't at the top of the stack, or cannot
452 store_extend_3(void *ptr, BOOL tainted, int oldsize, int newsize,
453 const char *func, int linenumber)
455 int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool;
456 int inc = newsize - oldsize;
457 int rounded_oldsize = oldsize;
459 if (oldsize < 0 || newsize < oldsize || newsize >= INT_MAX/2)
460 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
461 "bad memory extension requested (%d -> %d bytes) at %s %d",
462 oldsize, newsize, func, linenumber);
464 /* Check that the block being extended was already of the required taint status;
465 refuse to extend if not. */
467 if (is_tainted(ptr) != tainted)
470 if (rounded_oldsize % alignment != 0)
471 rounded_oldsize += alignment - (rounded_oldsize % alignment);
473 if (CS ptr + rounded_oldsize != CS (next_yield[pool]) ||
474 inc > yield_length[pool] + rounded_oldsize - oldsize)
477 /* Cut out the debugging stuff for utilities, but stop picky compilers from
480 #ifndef COMPILE_UTILITY
482 debug_printf("---%d Ext %6p %5d %-14s %4d\n", pool, ptr, newsize,
484 #endif /* COMPILE_UTILITY */
486 if (newsize % alignment != 0) newsize += alignment - (newsize % alignment);
487 next_yield[pool] = CS ptr + newsize;
488 yield_length[pool] -= newsize - rounded_oldsize;
489 (void) VALGRIND_MAKE_MEM_UNDEFINED(ptr + oldsize, inc);
497 is_pwr2_size(int len)
500 return (x & (x - 1)) == 0;
504 /*************************************************
505 * Back up to a previous point on the stack *
506 *************************************************/
508 /* This function resets the next pointer, freeing any subsequent whole blocks
509 that are now unused. Call with a cookie obtained from store_mark() only; do
510 not call with a pointer returned by store_get(). Both the untainted and tainted
511 pools corresposding to store_pool are reset.
514 ptr place to back up to
515 pool pool holding the pointer
516 func function from which called
517 linenumber line number in source file
523 internal_store_reset(void * ptr, int pool, const char *func, int linenumber)
526 storeblock * b = current_block[pool];
527 char * bc = CS b + ALIGNED_SIZEOF_STOREBLOCK;
528 int newlength, count;
529 #ifndef COMPILE_UTILITY
530 int oldmalloc = pool_malloc;
533 /* Last store operation was not a get */
535 store_last_get[pool] = NULL;
537 /* See if the place is in the current block - as it often will be. Otherwise,
538 search for the block in which it lies. */
540 if (CS ptr < bc || CS ptr > bc + b->length)
542 for (b = chainbase[pool]; b; b = b->next)
544 bc = CS b + ALIGNED_SIZEOF_STOREBLOCK;
545 if (CS ptr >= bc && CS ptr <= bc + b->length) break;
548 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal error: store_reset(%p) "
549 "failed: pool=%d %-14s %4d", ptr, pool, func, linenumber);
552 /* Back up, rounding to the alignment if necessary. When testing, flatten
553 the released memory. */
555 newlength = bc + b->length - CS ptr;
556 #ifndef COMPILE_UTILITY
559 assert_no_variables(ptr, newlength, func, linenumber);
560 if (f.running_in_test_harness)
562 (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength);
563 memset(ptr, 0xF0, newlength);
567 (void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength);
568 next_yield[pool] = CS ptr + (newlength % alignment);
569 count = yield_length[pool];
570 count = (yield_length[pool] = newlength - (newlength % alignment)) - count;
571 current_block[pool] = b;
573 /* Free any subsequent block. Do NOT free the first
574 successor, if our current block has less than 256 bytes left. This should
575 prevent us from flapping memory. However, keep this block only when it has
576 a power-of-two size so probably is not a custom inflated one. */
578 if ( yield_length[pool] < STOREPOOL_MIN_SIZE
580 && is_pwr2_size(b->next->length + ALIGNED_SIZEOF_STOREBLOCK))
583 #ifndef COMPILE_UTILITY
585 assert_no_variables(b, b->length + ALIGNED_SIZEOF_STOREBLOCK,
588 (void) VALGRIND_MAKE_MEM_NOACCESS(CS b + ALIGNED_SIZEOF_STOREBLOCK,
589 b->length - ALIGNED_SIZEOF_STOREBLOCK);
593 if (pool != POOL_CONFIG)
598 int siz = b->length + ALIGNED_SIZEOF_STOREBLOCK;
600 #ifndef COMPILE_UTILITY
602 assert_no_variables(b, b->length + ALIGNED_SIZEOF_STOREBLOCK,
609 if (pool != POOL_CONFIG)
610 internal_store_free(b, func, linenumber);
612 #ifndef RESTRICTED_MEMORY
613 if (store_block_order[pool] > 13) store_block_order[pool]--;
617 /* Cut out the debugging stuff for utilities, but stop picky compilers from
620 #ifndef COMPILE_UTILITY
622 debug_printf("---%d Rst %6p %5d %-14s %4d\tpool %d\n", pool, ptr,
623 count + oldmalloc - pool_malloc,
624 func, linenumber, pool_malloc);
625 #endif /* COMPILE_UTILITY */
630 store_reset_3(rmark r, const char *func, int linenumber)
634 if (store_pool >= POOL_TAINT_BASE)
635 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
636 "store_reset called for pool %d: %s %d\n", store_pool, func, linenumber);
638 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
639 "store_reset called with bad mark: %s %d\n", func, linenumber);
641 internal_store_reset(*ptr, store_pool + POOL_TAINT_BASE, func, linenumber);
642 internal_store_reset(ptr, store_pool, func, linenumber);
648 /* Free tail-end unused allocation. This lets us allocate a big chunk
649 early, for cases when we only discover later how much was really needed.
651 Can be called with a value from store_get(), or an offset after such. Only
652 the tainted or untainted pool that serviced the store_get() will be affected.
654 This is mostly a cut-down version of internal_store_reset().
655 XXX needs rationalising
659 store_release_above_3(void *ptr, const char *func, int linenumber)
661 /* Search all pools' "current" blocks. If it isn't one of those,
662 ignore it (it usually will be). */
664 for (int pool = 0; pool < nelem(current_block); pool++)
666 storeblock * b = current_block[pool];
668 int count, newlength;
673 bc = CS b + ALIGNED_SIZEOF_STOREBLOCK;
674 if (CS ptr < bc || CS ptr > bc + b->length)
677 /* Last store operation was not a get */
679 store_last_get[pool] = NULL;
681 /* Back up, rounding to the alignment if necessary. When testing, flatten
682 the released memory. */
684 newlength = bc + b->length - CS ptr;
685 #ifndef COMPILE_UTILITY
688 assert_no_variables(ptr, newlength, func, linenumber);
689 if (f.running_in_test_harness)
691 (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength);
692 memset(ptr, 0xF0, newlength);
696 (void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength);
697 next_yield[pool] = CS ptr + (newlength % alignment);
698 count = yield_length[pool];
699 count = (yield_length[pool] = newlength - (newlength % alignment)) - count;
701 /* Cut out the debugging stuff for utilities, but stop picky compilers from
704 #ifndef COMPILE_UTILITY
706 debug_printf("---%d Rel %6p %5d %-14s %4d\tpool %d\n", pool, ptr, count,
707 func, linenumber, pool_malloc);
711 #ifndef COMPILE_UTILITY
713 debug_printf("non-last memory release try: %s %d\n", func, linenumber);
720 store_mark_3(const char *func, int linenumber)
724 #ifndef COMPILE_UTILITY
726 debug_printf("---%d Mrk %-14s %4d\tpool %d\n",
727 store_pool, func, linenumber, pool_malloc);
728 #endif /* COMPILE_UTILITY */
730 if (store_pool >= POOL_TAINT_BASE)
731 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
732 "store_mark called for pool %d: %s %d\n", store_pool, func, linenumber);
734 /* Stash a mark for the tainted-twin release, in the untainted twin. Return
735 a cookie (actually the address in the untainted pool) to the caller.
736 Reset uses the cookie to recover the t-mark, winds back the tainted pool with it
737 and winds back the untainted pool with the cookie. */
739 p = store_get_3(sizeof(void *), FALSE, func, linenumber);
740 *p = store_get_3(0, TRUE, func, linenumber);
747 /************************************************
749 ************************************************/
751 /* This function checks that the pointer it is given is the first thing in a
752 block, and if so, releases that block.
755 block block of store to consider
756 func function from which called
757 linenumber line number in source file
763 store_release_3(void * block, int pool, const char * func, int linenumber)
765 /* It will never be the first block, so no need to check that. */
767 for (storeblock * b = chainbase[pool]; b; b = b->next)
769 storeblock * bb = b->next;
770 if (bb && CS block == CS bb + ALIGNED_SIZEOF_STOREBLOCK)
772 int siz = bb->length + ALIGNED_SIZEOF_STOREBLOCK;
778 /* Cut out the debugging stuff for utilities, but stop picky compilers
779 from giving warnings. */
781 #ifndef COMPILE_UTILITY
783 debug_printf("-Release %6p %-20s %4d %d\n", (void *)bb, func,
784 linenumber, pool_malloc);
786 if (f.running_in_test_harness)
787 memset(bb, 0xF0, bb->length+ALIGNED_SIZEOF_STOREBLOCK);
788 #endif /* COMPILE_UTILITY */
790 internal_store_free(bb, func, linenumber);
797 /************************************************
799 ************************************************/
801 /* Allocate a new block big enough to expend to the given size and
802 copy the current data into it. Free the old one if possible.
804 This function is specifically provided for use when reading very
805 long strings, e.g. header lines. When the string gets longer than a
806 complete block, it gets copied to a new block. It is helpful to free
807 the old block iff the previous copy of the string is at its start,
808 and therefore the only thing in it. Otherwise, for very long strings,
809 dead store can pile up somewhat disastrously. This function checks that
810 the pointer it is given is the first thing in a block, and that nothing
811 has been allocated since. If so, releases that block.
818 Returns: new location of data
822 store_newblock_3(void * block, BOOL tainted, int newsize, int len,
823 const char * func, int linenumber)
825 int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool;
826 BOOL release_ok = !tainted && store_last_get[pool] == block;
829 #if !defined(MACRO_PREDEF) && !defined(COMPILE_UTILITY)
830 if (is_tainted(block) != tainted)
831 die_tainted(US"store_newblock", CUS func, linenumber);
834 if (len < 0 || len > newsize)
835 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
836 "bad memory extension requested (%d -> %d bytes) at %s %d",
837 len, newsize, func, linenumber);
839 newtext = store_get(newsize, tainted);
840 memcpy(newtext, block, len);
841 if (release_ok) store_release_3(block, pool, func, linenumber);
842 return (void *)newtext;
848 /*************************************************
850 *************************************************/
852 /* Running out of store is a total disaster for exim. Some malloc functions
853 do not run happily on very small sizes, nor do they document this fact. This
854 function is called via the macro store_malloc().
857 size amount of store wanted
858 func function from which called
859 line line number in source file
861 Returns: pointer to gotten store (panic on failure)
865 internal_store_malloc(int size, const char *func, int line)
869 if (size < 0 || size >= INT_MAX/2)
870 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
871 "bad memory allocation requested (%d bytes) at %s %d",
874 size += sizeof(int); /* space to store the size, used under debug */
875 if (size < 16) size = 16;
877 if (!(yield = malloc((size_t)size)))
878 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to malloc %d bytes of memory: "
879 "called from line %d in %s", size, line, func);
881 #ifndef COMPILE_UTILITY
882 DEBUG(D_any) *(int *)yield = size;
884 yield = US yield + sizeof(int);
886 if ((nonpool_malloc += size) > max_nonpool_malloc)
887 max_nonpool_malloc = nonpool_malloc;
889 /* Cut out the debugging stuff for utilities, but stop picky compilers from
892 #ifndef COMPILE_UTILITY
893 /* If running in test harness, spend time making sure all the new store
894 is not filled with zeros so as to catch problems. */
896 if (f.running_in_test_harness)
897 memset(yield, 0xF0, (size_t)size - sizeof(int));
898 DEBUG(D_memory) debug_printf("--Malloc %6p %5d bytes\t%-20s %4d\tpool %5d nonpool %5d\n",
899 yield, size, func, line, pool_malloc, nonpool_malloc);
900 #endif /* COMPILE_UTILITY */
906 store_malloc_3(int size, const char *func, int linenumber)
908 if (n_nonpool_blocks++ > max_nonpool_blocks)
909 max_nonpool_blocks = n_nonpool_blocks;
910 return internal_store_malloc(size, func, linenumber);
914 /************************************************
916 ************************************************/
918 /* This function is called by the macro store_free().
921 block block of store to free
922 func function from which called
923 linenumber line number in source file
929 internal_store_free(void * block, const char * func, int linenumber)
931 uschar * p = US block - sizeof(int);
932 #ifndef COMPILE_UTILITY
933 DEBUG(D_any) nonpool_malloc -= *(int *)p;
934 DEBUG(D_memory) debug_printf("----Free %6p %5d bytes\t%-20s %4d\n", block, *(int *)p, func, linenumber);
940 store_free_3(void * block, const char * func, int linenumber)
943 internal_store_free(block, func, linenumber);
946 /******************************************************************************/
947 /* Stats output on process exit */
951 #ifndef COMPILE_UTILITY
954 debug_printf("----Exit nonpool max: %3d kB in %d blocks\n",
955 (max_nonpool_malloc+1023)/1024, max_nonpool_blocks);
956 debug_printf("----Exit npools max: %3d kB\n", max_pool_malloc/1024);
957 for (int i = 0; i < NPOOLS; i++)
958 debug_printf("----Exit pool %d max: %3d kB in %d blocks at order %u\t%s %s\n",
959 i, (maxbytes[i]+1023)/1024, maxblocks[i], maxorder[i],
960 poolclass[i], pooluse[i]);
966 /******************************************************************************/
967 /* Per-message pool management */
969 static rmark message_reset_point = NULL;
974 int oldpool = store_pool;
975 store_pool = POOL_MESSAGE;
976 if (!message_reset_point) message_reset_point = store_mark();
977 store_pool = oldpool;
980 void message_tidyup(void)
983 if (!message_reset_point) return;
984 oldpool = store_pool;
985 store_pool = POOL_MESSAGE;
986 message_reset_point = store_reset(message_reset_point);
987 store_pool = oldpool;