Commit | Line | Data |
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059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
f9ba5e22 | 5 | /* Copyright (c) University of Cambridge 1995 - 2018 */ |
f3ebb786 | 6 | /* Copyright (c) The Exim maintainers 2019 */ |
059ec3d9 PH |
7 | /* See the file NOTICE for conditions of use and distribution. */ |
8 | ||
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. | |
15 | ||
16 | Obviously the long-running processes (the daemon, the queue runner, and eximon) | |
17 | must take care not to eat store. | |
18 | ||
19 | The following different types of store are recognized: | |
20 | ||
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. | |
24 | ||
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. | |
29 | ||
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. | |
35 | ||
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 | |
38 | the lookup caching. | |
f3ebb786 JH |
39 | |
40 | . Orthogonal to the three pool types, there are two classes of memory: untainted | |
41 | and tainted. The latter is used for values derived from untrusted input, and | |
42 | the string-expansion mechanism refuses to operate on such values (obviously, | |
43 | it can expand an untainted value to return a tainted result). The classes | |
adc4ecf9 | 44 | are implemented by duplicating the three pool types. Pool resets are requested |
f3ebb786 | 45 | against the nontainted sibling and apply to both siblings. |
adc4ecf9 JH |
46 | |
47 | Only memory blocks requested for tainted use are regarded as tainted; anything | |
48 | else (including stack auto variables) is untainted. Care is needed when coding | |
49 | to not copy untrusted data into untainted memory, as downstream taint-checks | |
50 | would be avoided. | |
51 | ||
adc4ecf9 JH |
52 | Internally we currently use malloc for nontainted pools, and mmap for tainted |
53 | pools. The disparity is for speed of testing the taintedness of pointers; | |
54 | because Linux appears to use distinct non-overlapping address allocations for | |
55 | mmap vs. everything else, which means only two pointer-compares suffice for the | |
56 | test. Other OS' cannot use that optimisation, and a more lengthy test against | |
57 | the limits of tainted-pool allcations has to be done. | |
2fd4074d JH |
58 | |
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. Users of functions that modify existing allocations should | |
66 | check if a tainted source and an untainted destination is used, and fail instead | |
67 | (sprintf() being the classic case). | |
059ec3d9 PH |
68 | */ |
69 | ||
70 | ||
71 | #include "exim.h" | |
438257ba PP |
72 | /* keep config.h before memcheck.h, for NVALGRIND */ |
73 | #include "config.h" | |
74 | ||
f3ebb786 | 75 | #include <sys/mman.h> |
7f36d675 | 76 | #include "memcheck.h" |
059ec3d9 PH |
77 | |
78 | ||
79 | /* We need to know how to align blocks of data for general use. I'm not sure | |
80 | how to get an alignment factor in general. In the current world, a value of 8 | |
81 | is probably right, and this is sizeof(double) on some systems and sizeof(void | |
82 | *) on others, so take the larger of those. Since everything in this expression | |
83 | is a constant, the compiler should optimize it to a simple constant wherever it | |
84 | appears (I checked that gcc does do this). */ | |
85 | ||
86 | #define alignment \ | |
f3ebb786 | 87 | (sizeof(void *) > sizeof(double) ? sizeof(void *) : sizeof(double)) |
059ec3d9 PH |
88 | |
89 | /* store_reset() will not free the following block if the last used block has | |
90 | less than this much left in it. */ | |
91 | ||
92 | #define STOREPOOL_MIN_SIZE 256 | |
93 | ||
94 | /* Structure describing the beginning of each big block. */ | |
95 | ||
96 | typedef struct storeblock { | |
97 | struct storeblock *next; | |
98 | size_t length; | |
99 | } storeblock; | |
100 | ||
101 | /* Just in case we find ourselves on a system where the structure above has a | |
102 | length that is not a multiple of the alignment, set up a macro for the padded | |
103 | length. */ | |
104 | ||
105 | #define ALIGNED_SIZEOF_STOREBLOCK \ | |
106 | (((sizeof(storeblock) + alignment - 1) / alignment) * alignment) | |
107 | ||
f3ebb786 JH |
108 | /* Size of block to get from malloc to carve up into smaller ones. This |
109 | must be a multiple of the alignment. We assume that 8192 is going to be | |
110 | suitably aligned. */ | |
111 | ||
112 | #define STORE_BLOCK_SIZE (8192 - ALIGNED_SIZEOF_STOREBLOCK) | |
113 | ||
059ec3d9 PH |
114 | /* Variables holding data for the local pools of store. The current pool number |
115 | is held in store_pool, which is global so that it can be changed from outside. | |
116 | Setting the initial length values to -1 forces a malloc for the first call, | |
117 | even if the length is zero (which is used for getting a point to reset to). */ | |
118 | ||
f3ebb786 | 119 | int store_pool = POOL_MAIN; |
059ec3d9 | 120 | |
f3ebb786 JH |
121 | #define NPOOLS 6 |
122 | static storeblock *chainbase[NPOOLS]; | |
123 | static storeblock *current_block[NPOOLS]; | |
124 | static void *next_yield[NPOOLS]; | |
125 | static int yield_length[NPOOLS] = { -1, -1, -1, -1, -1, -1 }; | |
126 | ||
127 | /* The limits of the tainted pools. Tracking these on new allocations enables | |
128 | a fast is_tainted implementation. We assume the kernel only allocates mmaps using | |
129 | one side or the other of data+heap, not both. */ | |
130 | ||
6d5f5caf JH |
131 | void * tainted_base = (void *)-1; |
132 | void * tainted_top = (void *)0; | |
059ec3d9 PH |
133 | |
134 | /* pool_malloc holds the amount of memory used by the store pools; this goes up | |
135 | and down as store is reset or released. nonpool_malloc is the total got by | |
136 | malloc from other calls; this doesn't go down because it is just freed by | |
137 | pointer. */ | |
138 | ||
f3ebb786 JH |
139 | static int pool_malloc; |
140 | static int nonpool_malloc; | |
059ec3d9 PH |
141 | |
142 | /* This variable is set by store_get() to its yield, and by store_reset() to | |
143 | NULL. This enables string_cat() to optimize its store handling for very long | |
144 | strings. That's why the variable is global. */ | |
145 | ||
f3ebb786 JH |
146 | void *store_last_get[NPOOLS]; |
147 | ||
148 | /* These are purely for stats-gathering */ | |
149 | ||
150 | static int nbytes[NPOOLS]; /* current bytes allocated */ | |
151 | static int maxbytes[NPOOLS]; /* max number reached */ | |
152 | static int nblocks[NPOOLS]; /* current number of blocks allocated */ | |
153 | static int maxblocks[NPOOLS]; | |
154 | static int n_nonpool_blocks; /* current number of direct store_malloc() blocks */ | |
155 | static int max_nonpool_blocks; | |
156 | static int max_pool_malloc; /* max value for pool_malloc */ | |
157 | static int max_nonpool_malloc; /* max value for nonpool_malloc */ | |
158 | ||
159 | ||
81a559c8 | 160 | #ifndef COMPILE_UTILITY |
f3ebb786 JH |
161 | static const uschar * pooluse[NPOOLS] = { |
162 | [POOL_MAIN] = US"main", | |
163 | [POOL_PERM] = US"perm", | |
164 | [POOL_SEARCH] = US"search", | |
165 | [POOL_TAINT_MAIN] = US"main", | |
166 | [POOL_TAINT_PERM] = US"perm", | |
167 | [POOL_TAINT_SEARCH] = US"search", | |
168 | }; | |
169 | static const uschar * poolclass[NPOOLS] = { | |
170 | [POOL_MAIN] = US"untainted", | |
171 | [POOL_PERM] = US"untainted", | |
172 | [POOL_SEARCH] = US"untainted", | |
173 | [POOL_TAINT_MAIN] = US"tainted", | |
174 | [POOL_TAINT_PERM] = US"tainted", | |
175 | [POOL_TAINT_SEARCH] = US"tainted", | |
176 | }; | |
81a559c8 | 177 | #endif |
f3ebb786 JH |
178 | |
179 | ||
180 | static void * store_mmap(int, const char *, int); | |
181 | static void * internal_store_malloc(int, const char *, int); | |
65766f1b JH |
182 | static void internal_untainted_free(void *, const char *, int linenumber); |
183 | static void internal_tainted_free(storeblock *, const char *, int linenumber); | |
f3ebb786 JH |
184 | |
185 | /******************************************************************************/ | |
186 | ||
f096bccc | 187 | #ifndef TAINT_CHECK_FAST |
2fd4074d JH |
188 | /* Test if a pointer refers to tainted memory. |
189 | ||
190 | Slower version check, for use when platform intermixes malloc and mmap area | |
191 | addresses. Test against the current-block of all tainted pools first, then all | |
192 | blocks of all tainted pools. | |
193 | ||
194 | Return: TRUE iff tainted | |
195 | */ | |
14ca5d2a JH |
196 | |
197 | BOOL | |
198 | is_tainted_fn(const void * p) | |
199 | { | |
200 | storeblock * b; | |
201 | int pool; | |
202 | ||
2fd4074d | 203 | for (pool = POOL_TAINT_BASE; pool < nelem(chainbase); pool++) |
14ca5d2a JH |
204 | if ((b = current_block[pool])) |
205 | { | |
206 | char * bc = CS b + ALIGNED_SIZEOF_STOREBLOCK; | |
2fd4074d | 207 | if (CS p >= bc && CS p <= bc + b->length) return TRUE; |
14ca5d2a JH |
208 | } |
209 | ||
2fd4074d | 210 | for (pool = POOL_TAINT_BASE; pool < nelem(chainbase); pool++) |
14ca5d2a JH |
211 | for (b = chainbase[pool]; b; b = b->next) |
212 | { | |
213 | char * bc = CS b + ALIGNED_SIZEOF_STOREBLOCK; | |
2fd4074d | 214 | if (CS p >= bc && CS p <= bc + b->length) return TRUE; |
14ca5d2a JH |
215 | } |
216 | return FALSE; | |
14ca5d2a | 217 | } |
f096bccc | 218 | #endif |
14ca5d2a JH |
219 | |
220 | ||
f3ebb786 JH |
221 | void |
222 | die_tainted(const uschar * msg, const uschar * func, int line) | |
223 | { | |
224 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Taint mismatch, %s: %s %d\n", | |
225 | msg, func, line); | |
226 | } | |
059ec3d9 PH |
227 | |
228 | ||
229 | /************************************************* | |
230 | * Get a block from the current pool * | |
231 | *************************************************/ | |
232 | ||
233 | /* Running out of store is a total disaster. This function is called via the | |
234 | macro store_get(). It passes back a block of store within the current big | |
235 | block, getting a new one if necessary. The address is saved in | |
236 | store_last_was_get. | |
237 | ||
238 | Arguments: | |
adc4ecf9 JH |
239 | size amount wanted, bytes |
240 | tainted class: set to true for untrusted data (eg. from smtp input) | |
f3ebb786 JH |
241 | func function from which called |
242 | linenumber line number in source file | |
059ec3d9 PH |
243 | |
244 | Returns: pointer to store (panic on malloc failure) | |
245 | */ | |
246 | ||
247 | void * | |
f3ebb786 | 248 | store_get_3(int size, BOOL tainted, const char *func, int linenumber) |
059ec3d9 | 249 | { |
f3ebb786 JH |
250 | int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool; |
251 | ||
059ec3d9 PH |
252 | /* Round up the size to a multiple of the alignment. Although this looks a |
253 | messy statement, because "alignment" is a constant expression, the compiler can | |
254 | do a reasonable job of optimizing, especially if the value of "alignment" is a | |
255 | power of two. I checked this with -O2, and gcc did very well, compiling it to 4 | |
256 | instructions on a Sparc (alignment = 8). */ | |
257 | ||
258 | if (size % alignment != 0) size += alignment - (size % alignment); | |
259 | ||
260 | /* If there isn't room in the current block, get a new one. The minimum | |
261 | size is STORE_BLOCK_SIZE, and we would expect this to be the norm, since | |
262 | these functions are mostly called for small amounts of store. */ | |
263 | ||
f3ebb786 | 264 | if (size > yield_length[pool]) |
059ec3d9 | 265 | { |
f3ebb786 | 266 | int length = size <= STORE_BLOCK_SIZE ? STORE_BLOCK_SIZE : size; |
059ec3d9 | 267 | int mlength = length + ALIGNED_SIZEOF_STOREBLOCK; |
f3ebb786 | 268 | storeblock * newblock; |
059ec3d9 PH |
269 | |
270 | /* Sometimes store_reset() may leave a block for us; check if we can use it */ | |
271 | ||
f3ebb786 | 272 | if ( (newblock = current_block[pool]) |
64073d9c JH |
273 | && (newblock = newblock->next) |
274 | && newblock->length < length | |
275 | ) | |
059ec3d9 | 276 | { |
64073d9c | 277 | /* Give up on this block, because it's too small */ |
f3ebb786 JH |
278 | nblocks[pool]--; |
279 | if (pool < POOL_TAINT_BASE) | |
65766f1b | 280 | internal_untainted_free(newblock, func, linenumber); |
f3ebb786 | 281 | else |
65766f1b | 282 | internal_tainted_free(newblock, func, linenumber); |
64073d9c | 283 | newblock = NULL; |
059ec3d9 PH |
284 | } |
285 | ||
286 | /* If there was no free block, get a new one */ | |
287 | ||
64073d9c | 288 | if (!newblock) |
059ec3d9 | 289 | { |
f3ebb786 JH |
290 | if ((nbytes[pool] += mlength) > maxbytes[pool]) |
291 | maxbytes[pool] = nbytes[pool]; | |
292 | if ((pool_malloc += mlength) > max_pool_malloc) /* Used in pools */ | |
293 | max_pool_malloc = pool_malloc; | |
294 | nonpool_malloc -= mlength; /* Exclude from overall total */ | |
295 | if (++nblocks[pool] > maxblocks[pool]) | |
296 | maxblocks[pool] = nblocks[pool]; | |
297 | ||
298 | newblock = tainted | |
299 | ? store_mmap(mlength, func, linenumber) | |
300 | : internal_store_malloc(mlength, func, linenumber); | |
059ec3d9 PH |
301 | newblock->next = NULL; |
302 | newblock->length = length; | |
f3ebb786 JH |
303 | |
304 | if (!chainbase[pool]) | |
305 | chainbase[pool] = newblock; | |
64073d9c | 306 | else |
f3ebb786 | 307 | current_block[pool]->next = newblock; |
059ec3d9 PH |
308 | } |
309 | ||
f3ebb786 JH |
310 | current_block[pool] = newblock; |
311 | yield_length[pool] = newblock->length; | |
312 | next_yield[pool] = | |
313 | (void *)(CS current_block[pool] + ALIGNED_SIZEOF_STOREBLOCK); | |
314 | (void) VALGRIND_MAKE_MEM_NOACCESS(next_yield[pool], yield_length[pool]); | |
059ec3d9 PH |
315 | } |
316 | ||
317 | /* There's (now) enough room in the current block; the yield is the next | |
318 | pointer. */ | |
319 | ||
f3ebb786 | 320 | store_last_get[pool] = next_yield[pool]; |
059ec3d9 PH |
321 | |
322 | /* Cut out the debugging stuff for utilities, but stop picky compilers from | |
323 | giving warnings. */ | |
324 | ||
325 | #ifdef COMPILE_UTILITY | |
f3ebb786 | 326 | func = func; |
059ec3d9 PH |
327 | linenumber = linenumber; |
328 | #else | |
329 | DEBUG(D_memory) | |
f3ebb786 JH |
330 | debug_printf("---%d Get %6p %5d %-14s %4d\n", pool, |
331 | store_last_get[pool], size, func, linenumber); | |
059ec3d9 PH |
332 | #endif /* COMPILE_UTILITY */ |
333 | ||
f3ebb786 | 334 | (void) VALGRIND_MAKE_MEM_UNDEFINED(store_last_get[pool], size); |
059ec3d9 PH |
335 | /* Update next pointer and number of bytes left in the current block. */ |
336 | ||
f3ebb786 JH |
337 | next_yield[pool] = (void *)(CS next_yield[pool] + size); |
338 | yield_length[pool] -= size; | |
339 | return store_last_get[pool]; | |
059ec3d9 PH |
340 | } |
341 | ||
342 | ||
343 | ||
344 | /************************************************* | |
345 | * Get a block from the PERM pool * | |
346 | *************************************************/ | |
347 | ||
348 | /* This is just a convenience function, useful when just a single block is to | |
349 | be obtained. | |
350 | ||
351 | Arguments: | |
352 | size amount wanted | |
f3ebb786 JH |
353 | func function from which called |
354 | linenumber line number in source file | |
059ec3d9 PH |
355 | |
356 | Returns: pointer to store (panic on malloc failure) | |
357 | */ | |
358 | ||
359 | void * | |
f3ebb786 | 360 | store_get_perm_3(int size, BOOL tainted, const char *func, int linenumber) |
059ec3d9 PH |
361 | { |
362 | void *yield; | |
363 | int old_pool = store_pool; | |
364 | store_pool = POOL_PERM; | |
f3ebb786 | 365 | yield = store_get_3(size, tainted, func, linenumber); |
059ec3d9 PH |
366 | store_pool = old_pool; |
367 | return yield; | |
368 | } | |
369 | ||
370 | ||
371 | ||
372 | /************************************************* | |
373 | * Extend a block if it is at the top * | |
374 | *************************************************/ | |
375 | ||
376 | /* While reading strings of unknown length, it is often the case that the | |
377 | string is being read into the block at the top of the stack. If it needs to be | |
f3ebb786 | 378 | extended, it is more efficient just to extend within the top block rather than |
059ec3d9 PH |
379 | allocate a new block and then have to copy the data. This function is provided |
380 | for the use of string_cat(), but of course can be used elsewhere too. | |
f3ebb786 | 381 | The block itself is not expanded; only the top allocation from it. |
059ec3d9 PH |
382 | |
383 | Arguments: | |
384 | ptr pointer to store block | |
385 | oldsize current size of the block, as requested by user | |
386 | newsize new size required | |
f3ebb786 | 387 | func function from which called |
059ec3d9 PH |
388 | linenumber line number in source file |
389 | ||
390 | Returns: TRUE if the block is at the top of the stack and has been | |
391 | extended; FALSE if it isn't at the top of the stack, or cannot | |
392 | be extended | |
393 | */ | |
394 | ||
395 | BOOL | |
f3ebb786 JH |
396 | store_extend_3(void *ptr, BOOL tainted, int oldsize, int newsize, |
397 | const char *func, int linenumber) | |
059ec3d9 | 398 | { |
f3ebb786 | 399 | int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool; |
059ec3d9 PH |
400 | int inc = newsize - oldsize; |
401 | int rounded_oldsize = oldsize; | |
402 | ||
f3ebb786 JH |
403 | /* Check that the block being extended was already of the required taint status; |
404 | refuse to extend if not. */ | |
405 | ||
406 | if (is_tainted(ptr) != tainted) | |
407 | return FALSE; | |
408 | ||
059ec3d9 PH |
409 | if (rounded_oldsize % alignment != 0) |
410 | rounded_oldsize += alignment - (rounded_oldsize % alignment); | |
411 | ||
f3ebb786 JH |
412 | if (CS ptr + rounded_oldsize != CS (next_yield[pool]) || |
413 | inc > yield_length[pool] + rounded_oldsize - oldsize) | |
059ec3d9 PH |
414 | return FALSE; |
415 | ||
416 | /* Cut out the debugging stuff for utilities, but stop picky compilers from | |
417 | giving warnings. */ | |
418 | ||
419 | #ifdef COMPILE_UTILITY | |
f3ebb786 | 420 | func = func; |
059ec3d9 PH |
421 | linenumber = linenumber; |
422 | #else | |
423 | DEBUG(D_memory) | |
f3ebb786 JH |
424 | debug_printf("---%d Ext %6p %5d %-14s %4d\n", pool, ptr, newsize, |
425 | func, linenumber); | |
059ec3d9 PH |
426 | #endif /* COMPILE_UTILITY */ |
427 | ||
428 | if (newsize % alignment != 0) newsize += alignment - (newsize % alignment); | |
f3ebb786 JH |
429 | next_yield[pool] = CS ptr + newsize; |
430 | yield_length[pool] -= newsize - rounded_oldsize; | |
4d8bb202 | 431 | (void) VALGRIND_MAKE_MEM_UNDEFINED(ptr + oldsize, inc); |
059ec3d9 PH |
432 | return TRUE; |
433 | } | |
434 | ||
435 | ||
436 | ||
437 | ||
438 | /************************************************* | |
439 | * Back up to a previous point on the stack * | |
440 | *************************************************/ | |
441 | ||
442 | /* This function resets the next pointer, freeing any subsequent whole blocks | |
f3ebb786 JH |
443 | that are now unused. Call with a cookie obtained from store_mark() only; do |
444 | not call with a pointer returned by store_get(). Both the untainted and tainted | |
445 | pools corresposding to store_pool are reset. | |
059ec3d9 PH |
446 | |
447 | Arguments: | |
f3ebb786 JH |
448 | r place to back up to |
449 | func function from which called | |
059ec3d9 PH |
450 | linenumber line number in source file |
451 | ||
452 | Returns: nothing | |
453 | */ | |
454 | ||
f3ebb786 JH |
455 | static void |
456 | internal_store_reset(void * ptr, int pool, const char *func, int linenumber) | |
059ec3d9 | 457 | { |
cf0812d5 | 458 | storeblock * bb; |
f3ebb786 | 459 | storeblock * b = current_block[pool]; |
cf0812d5 | 460 | char * bc = CS b + ALIGNED_SIZEOF_STOREBLOCK; |
f3ebb786 JH |
461 | int newlength, count; |
462 | #ifndef COMPILE_UTILITY | |
463 | int oldmalloc = pool_malloc; | |
464 | #endif | |
059ec3d9 PH |
465 | |
466 | /* Last store operation was not a get */ | |
467 | ||
f3ebb786 | 468 | store_last_get[pool] = NULL; |
059ec3d9 PH |
469 | |
470 | /* See if the place is in the current block - as it often will be. Otherwise, | |
471 | search for the block in which it lies. */ | |
472 | ||
cf0812d5 | 473 | if (CS ptr < bc || CS ptr > bc + b->length) |
059ec3d9 | 474 | { |
f3ebb786 | 475 | for (b = chainbase[pool]; b; b = b->next) |
059ec3d9 | 476 | { |
cf0812d5 JH |
477 | bc = CS b + ALIGNED_SIZEOF_STOREBLOCK; |
478 | if (CS ptr >= bc && CS ptr <= bc + b->length) break; | |
059ec3d9 | 479 | } |
cf0812d5 | 480 | if (!b) |
438257ba | 481 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal error: store_reset(%p) " |
f3ebb786 | 482 | "failed: pool=%d %-14s %4d", ptr, pool, func, linenumber); |
059ec3d9 PH |
483 | } |
484 | ||
485 | /* Back up, rounding to the alignment if necessary. When testing, flatten | |
486 | the released memory. */ | |
487 | ||
cf0812d5 | 488 | newlength = bc + b->length - CS ptr; |
059ec3d9 | 489 | #ifndef COMPILE_UTILITY |
65a32f85 | 490 | if (debug_store) |
2c9f7ff8 | 491 | { |
f3ebb786 | 492 | assert_no_variables(ptr, newlength, func, linenumber); |
8768d548 | 493 | if (f.running_in_test_harness) |
64073d9c JH |
494 | { |
495 | (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength); | |
496 | memset(ptr, 0xF0, newlength); | |
497 | } | |
2c9f7ff8 | 498 | } |
059ec3d9 | 499 | #endif |
4d8bb202 | 500 | (void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength); |
f3ebb786 JH |
501 | next_yield[pool] = CS ptr + (newlength % alignment); |
502 | count = yield_length[pool]; | |
503 | count = (yield_length[pool] = newlength - (newlength % alignment)) - count; | |
504 | current_block[pool] = b; | |
505 | ||
506 | /* Free any subsequent block. Do NOT free the first | |
507 | successor, if our current block has less than 256 bytes left. This should | |
508 | prevent us from flapping memory. However, keep this block only when it has | |
509 | the default size. */ | |
510 | ||
511 | if ( yield_length[pool] < STOREPOOL_MIN_SIZE | |
512 | && b->next | |
513 | && b->next->length == STORE_BLOCK_SIZE) | |
7f36d675 | 514 | { |
059ec3d9 | 515 | b = b->next; |
cf0812d5 | 516 | #ifndef COMPILE_UTILITY |
65a32f85 | 517 | if (debug_store) |
cf0812d5 | 518 | assert_no_variables(b, b->length + ALIGNED_SIZEOF_STOREBLOCK, |
f3ebb786 | 519 | func, linenumber); |
cf0812d5 JH |
520 | #endif |
521 | (void) VALGRIND_MAKE_MEM_NOACCESS(CS b + ALIGNED_SIZEOF_STOREBLOCK, | |
4d8bb202 | 522 | b->length - ALIGNED_SIZEOF_STOREBLOCK); |
7f36d675 | 523 | } |
059ec3d9 PH |
524 | |
525 | bb = b->next; | |
526 | b->next = NULL; | |
527 | ||
cf0812d5 | 528 | while ((b = bb)) |
059ec3d9 | 529 | { |
f3ebb786 | 530 | int siz = b->length + ALIGNED_SIZEOF_STOREBLOCK; |
cf0812d5 | 531 | #ifndef COMPILE_UTILITY |
65a32f85 | 532 | if (debug_store) |
cf0812d5 | 533 | assert_no_variables(b, b->length + ALIGNED_SIZEOF_STOREBLOCK, |
f3ebb786 | 534 | func, linenumber); |
cf0812d5 | 535 | #endif |
059ec3d9 | 536 | bb = bb->next; |
f3ebb786 JH |
537 | nbytes[pool] -= siz; |
538 | pool_malloc -= siz; | |
539 | nblocks[pool]--; | |
540 | if (pool < POOL_TAINT_BASE) | |
65766f1b | 541 | internal_untainted_free(b, func, linenumber); |
f3ebb786 | 542 | else |
65766f1b | 543 | internal_tainted_free(b, func, linenumber); |
059ec3d9 PH |
544 | } |
545 | ||
546 | /* Cut out the debugging stuff for utilities, but stop picky compilers from | |
547 | giving warnings. */ | |
548 | ||
549 | #ifdef COMPILE_UTILITY | |
f3ebb786 | 550 | func = func; |
059ec3d9 PH |
551 | linenumber = linenumber; |
552 | #else | |
553 | DEBUG(D_memory) | |
f3ebb786 JH |
554 | debug_printf("---%d Rst %6p %5d %-14s %4d %d\n", pool, ptr, |
555 | count + oldmalloc - pool_malloc, | |
556 | func, linenumber, pool_malloc); | |
557 | #endif /* COMPILE_UTILITY */ | |
558 | } | |
559 | ||
560 | ||
561 | rmark | |
562 | store_reset_3(rmark r, int pool, const char *func, int linenumber) | |
563 | { | |
564 | void ** ptr = r; | |
565 | ||
566 | if (pool >= POOL_TAINT_BASE) | |
567 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, | |
568 | "store_reset called for pool %d: %s %d\n", pool, func, linenumber); | |
569 | if (!r) | |
570 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, | |
571 | "store_reset called with bad mark: %s %d\n", func, linenumber); | |
572 | ||
573 | internal_store_reset(*ptr, pool + POOL_TAINT_BASE, func, linenumber); | |
574 | internal_store_reset(ptr, pool, func, linenumber); | |
575 | return NULL; | |
576 | } | |
577 | ||
578 | ||
579 | ||
580 | /* Free tail-end unused allocation. This lets us allocate a big chunk | |
581 | early, for cases when we only discover later how much was really needed. | |
582 | ||
583 | Can be called with a value from store_get(), or an offset after such. Only | |
584 | the tainted or untainted pool that serviced the store_get() will be affected. | |
585 | ||
586 | This is mostly a cut-down version of internal_store_reset(). | |
587 | XXX needs rationalising | |
588 | */ | |
589 | ||
590 | void | |
591 | store_release_above_3(void *ptr, const char *func, int linenumber) | |
592 | { | |
593 | /* Search all pools' "current" blocks. If it isn't one of those, | |
594 | ignore it (it usually will be). */ | |
595 | ||
596 | for (int pool = 0; pool < nelem(current_block); pool++) | |
059ec3d9 | 597 | { |
f3ebb786 JH |
598 | storeblock * b = current_block[pool]; |
599 | char * bc; | |
600 | int count, newlength; | |
601 | ||
602 | if (!b) | |
603 | continue; | |
604 | ||
605 | bc = CS b + ALIGNED_SIZEOF_STOREBLOCK; | |
606 | if (CS ptr < bc || CS ptr > bc + b->length) | |
607 | continue; | |
608 | ||
609 | /* Last store operation was not a get */ | |
610 | ||
611 | store_last_get[pool] = NULL; | |
612 | ||
613 | /* Back up, rounding to the alignment if necessary. When testing, flatten | |
614 | the released memory. */ | |
615 | ||
616 | newlength = bc + b->length - CS ptr; | |
617 | #ifndef COMPILE_UTILITY | |
618 | if (debug_store) | |
619 | { | |
620 | assert_no_variables(ptr, newlength, func, linenumber); | |
621 | if (f.running_in_test_harness) | |
622 | { | |
623 | (void) VALGRIND_MAKE_MEM_DEFINED(ptr, newlength); | |
624 | memset(ptr, 0xF0, newlength); | |
625 | } | |
626 | } | |
627 | #endif | |
628 | (void) VALGRIND_MAKE_MEM_NOACCESS(ptr, newlength); | |
629 | next_yield[pool] = CS ptr + (newlength % alignment); | |
630 | count = yield_length[pool]; | |
631 | count = (yield_length[pool] = newlength - (newlength % alignment)) - count; | |
632 | ||
633 | /* Cut out the debugging stuff for utilities, but stop picky compilers from | |
634 | giving warnings. */ | |
635 | ||
636 | #ifdef COMPILE_UTILITY | |
637 | func = func; | |
638 | linenumber = linenumber; | |
639 | #else | |
640 | DEBUG(D_memory) | |
641 | debug_printf("---%d Rel %6p %5d %-14s %4d %d\n", pool, ptr, count, | |
642 | func, linenumber, pool_malloc); | |
643 | #endif | |
644 | return; | |
059ec3d9 | 645 | } |
f3ebb786 JH |
646 | #ifndef COMPILE_UTILITY |
647 | DEBUG(D_memory) | |
648 | debug_printf("non-last memory release try: %s %d\n", func, linenumber); | |
649 | #endif | |
059ec3d9 PH |
650 | } |
651 | ||
652 | ||
653 | ||
f3ebb786 JH |
654 | rmark |
655 | store_mark_3(const char *func, int linenumber) | |
656 | { | |
657 | void ** p; | |
658 | ||
659 | if (store_pool >= POOL_TAINT_BASE) | |
660 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, | |
661 | "store_mark called for pool %d: %s %d\n", store_pool, func, linenumber); | |
662 | ||
663 | /* Stash a mark for the tainted-twin release, in the untainted twin. Return | |
664 | a cookie (actually the address in the untainted pool) to the caller. | |
665 | Reset uses the cookie to recover the t-mark, winds back the tainted pool with it | |
666 | and winds back the untainted pool with the cookie. */ | |
667 | ||
668 | p = store_get_3(sizeof(void *), FALSE, func, linenumber); | |
669 | *p = store_get_3(0, TRUE, func, linenumber); | |
670 | return p; | |
671 | } | |
672 | ||
673 | ||
059ec3d9 PH |
674 | |
675 | ||
676 | /************************************************ | |
677 | * Release store * | |
678 | ************************************************/ | |
679 | ||
459fca58 JH |
680 | /* This function checks that the pointer it is given is the first thing in a |
681 | block, and if so, releases that block. | |
059ec3d9 PH |
682 | |
683 | Arguments: | |
684 | block block of store to consider | |
f3ebb786 | 685 | func function from which called |
059ec3d9 PH |
686 | linenumber line number in source file |
687 | ||
688 | Returns: nothing | |
689 | */ | |
690 | ||
459fca58 | 691 | static void |
f3ebb786 | 692 | store_release_3(void * block, int pool, const char * func, int linenumber) |
059ec3d9 | 693 | { |
059ec3d9 PH |
694 | /* It will never be the first block, so no need to check that. */ |
695 | ||
f3ebb786 | 696 | for (storeblock * b = chainbase[pool]; b; b = b->next) |
059ec3d9 | 697 | { |
459fca58 JH |
698 | storeblock * bb = b->next; |
699 | if (bb && CS block == CS bb + ALIGNED_SIZEOF_STOREBLOCK) | |
059ec3d9 | 700 | { |
f3ebb786 | 701 | int siz = bb->length + ALIGNED_SIZEOF_STOREBLOCK; |
059ec3d9 | 702 | b->next = bb->next; |
f3ebb786 JH |
703 | nbytes[pool] -= siz; |
704 | pool_malloc -= siz; | |
705 | nblocks[pool]--; | |
059ec3d9 PH |
706 | |
707 | /* Cut out the debugging stuff for utilities, but stop picky compilers | |
708 | from giving warnings. */ | |
709 | ||
459fca58 | 710 | #ifdef COMPILE_UTILITY |
f3ebb786 | 711 | func = func; |
059ec3d9 | 712 | linenumber = linenumber; |
459fca58 | 713 | #else |
059ec3d9 | 714 | DEBUG(D_memory) |
f3ebb786 JH |
715 | debug_printf("-Release %6p %-20s %4d %d\n", (void *)bb, func, |
716 | linenumber, pool_malloc); | |
459fca58 | 717 | |
8768d548 | 718 | if (f.running_in_test_harness) |
059ec3d9 | 719 | memset(bb, 0xF0, bb->length+ALIGNED_SIZEOF_STOREBLOCK); |
459fca58 | 720 | #endif /* COMPILE_UTILITY */ |
059ec3d9 PH |
721 | |
722 | free(bb); | |
723 | return; | |
724 | } | |
725 | } | |
726 | } | |
727 | ||
728 | ||
459fca58 JH |
729 | /************************************************ |
730 | * Move store * | |
731 | ************************************************/ | |
732 | ||
733 | /* Allocate a new block big enough to expend to the given size and | |
734 | copy the current data into it. Free the old one if possible. | |
735 | ||
736 | This function is specifically provided for use when reading very | |
737 | long strings, e.g. header lines. When the string gets longer than a | |
738 | complete block, it gets copied to a new block. It is helpful to free | |
739 | the old block iff the previous copy of the string is at its start, | |
740 | and therefore the only thing in it. Otherwise, for very long strings, | |
741 | dead store can pile up somewhat disastrously. This function checks that | |
742 | the pointer it is given is the first thing in a block, and that nothing | |
743 | has been allocated since. If so, releases that block. | |
744 | ||
745 | Arguments: | |
746 | block | |
747 | newsize | |
748 | len | |
749 | ||
750 | Returns: new location of data | |
751 | */ | |
752 | ||
753 | void * | |
f3ebb786 JH |
754 | store_newblock_3(void * block, BOOL tainted, int newsize, int len, |
755 | const char * func, int linenumber) | |
459fca58 | 756 | { |
f3ebb786 JH |
757 | int pool = tainted ? store_pool + POOL_TAINT_BASE : store_pool; |
758 | BOOL release_ok = !tainted && store_last_get[pool] == block; | |
759 | uschar * newtext; | |
760 | ||
aaabfafe | 761 | #ifndef MACRO_PREDEF |
f3ebb786 JH |
762 | if (is_tainted(block) != tainted) |
763 | die_tainted(US"store_newblock", CUS func, linenumber); | |
aaabfafe | 764 | #endif |
459fca58 | 765 | |
f3ebb786 | 766 | newtext = store_get(newsize, tainted); |
459fca58 | 767 | memcpy(newtext, block, len); |
f3ebb786 | 768 | if (release_ok) store_release_3(block, pool, func, linenumber); |
459fca58 JH |
769 | return (void *)newtext; |
770 | } | |
771 | ||
772 | ||
059ec3d9 PH |
773 | |
774 | ||
f3ebb786 JH |
775 | /******************************************************************************/ |
776 | static void * | |
777 | store_alloc_tail(void * yield, int size, const char * func, int line, | |
778 | const uschar * type) | |
779 | { | |
780 | if ((nonpool_malloc += size) > max_nonpool_malloc) | |
781 | max_nonpool_malloc = nonpool_malloc; | |
782 | ||
783 | /* Cut out the debugging stuff for utilities, but stop picky compilers from | |
784 | giving warnings. */ | |
785 | ||
786 | #ifdef COMPILE_UTILITY | |
787 | func = func; line = line; type = type; | |
788 | #else | |
789 | ||
790 | /* If running in test harness, spend time making sure all the new store | |
791 | is not filled with zeros so as to catch problems. */ | |
792 | ||
793 | if (f.running_in_test_harness) | |
794 | memset(yield, 0xF0, (size_t)size); | |
795 | DEBUG(D_memory) debug_printf("--%6s %6p %5d bytes\t%-14s %4d\tpool %5d nonpool %5d\n", | |
796 | type, yield, size, func, line, pool_malloc, nonpool_malloc); | |
797 | #endif /* COMPILE_UTILITY */ | |
798 | ||
799 | return yield; | |
800 | } | |
801 | ||
802 | /************************************************* | |
803 | * Mmap store * | |
804 | *************************************************/ | |
805 | ||
806 | static void * | |
807 | store_mmap(int size, const char * func, int line) | |
808 | { | |
809 | void * yield, * top; | |
810 | ||
811 | if (size < 16) size = 16; | |
812 | ||
813 | if (!(yield = mmap(NULL, (size_t)size, | |
814 | PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0))) | |
815 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to mmap %d bytes of memory: " | |
816 | "called from line %d of %s", size, line, func); | |
817 | ||
818 | if (yield < tainted_base) tainted_base = yield; | |
6d95688d | 819 | if ((top = US yield + size) > tainted_top) tainted_top = top; |
f3ebb786 JH |
820 | |
821 | return store_alloc_tail(yield, size, func, line, US"Mmap"); | |
822 | } | |
823 | ||
059ec3d9 PH |
824 | /************************************************* |
825 | * Malloc store * | |
826 | *************************************************/ | |
827 | ||
828 | /* Running out of store is a total disaster for exim. Some malloc functions | |
829 | do not run happily on very small sizes, nor do they document this fact. This | |
830 | function is called via the macro store_malloc(). | |
831 | ||
832 | Arguments: | |
833 | size amount of store wanted | |
f3ebb786 | 834 | func function from which called |
059ec3d9 PH |
835 | linenumber line number in source file |
836 | ||
837 | Returns: pointer to gotten store (panic on failure) | |
838 | */ | |
839 | ||
f3ebb786 JH |
840 | static void * |
841 | internal_store_malloc(int size, const char *func, int linenumber) | |
059ec3d9 | 842 | { |
f3ebb786 | 843 | void * yield; |
059ec3d9 PH |
844 | |
845 | if (size < 16) size = 16; | |
059ec3d9 | 846 | |
40c90bca | 847 | if (!(yield = malloc((size_t)size))) |
059ec3d9 | 848 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to malloc %d bytes of memory: " |
f3ebb786 | 849 | "called from line %d in %s", size, linenumber, func); |
059ec3d9 | 850 | |
f3ebb786 JH |
851 | return store_alloc_tail(yield, size, func, linenumber, US"Malloc"); |
852 | } | |
059ec3d9 | 853 | |
f3ebb786 JH |
854 | void * |
855 | store_malloc_3(int size, const char *func, int linenumber) | |
856 | { | |
857 | if (n_nonpool_blocks++ > max_nonpool_blocks) | |
858 | max_nonpool_blocks = n_nonpool_blocks; | |
859 | return internal_store_malloc(size, func, linenumber); | |
059ec3d9 PH |
860 | } |
861 | ||
862 | ||
863 | /************************************************ | |
864 | * Free store * | |
865 | ************************************************/ | |
866 | ||
867 | /* This function is called by the macro store_free(). | |
868 | ||
869 | Arguments: | |
870 | block block of store to free | |
f3ebb786 | 871 | func function from which called |
059ec3d9 PH |
872 | linenumber line number in source file |
873 | ||
874 | Returns: nothing | |
875 | */ | |
876 | ||
f3ebb786 | 877 | static void |
65766f1b | 878 | internal_untainted_free(void * block, const char * func, int linenumber) |
059ec3d9 PH |
879 | { |
880 | #ifdef COMPILE_UTILITY | |
f3ebb786 | 881 | func = func; |
059ec3d9 PH |
882 | linenumber = linenumber; |
883 | #else | |
884 | DEBUG(D_memory) | |
f3ebb786 | 885 | debug_printf("----Free %6p %-20s %4d\n", block, func, linenumber); |
059ec3d9 PH |
886 | #endif /* COMPILE_UTILITY */ |
887 | free(block); | |
888 | } | |
889 | ||
f3ebb786 | 890 | void |
65766f1b | 891 | store_free_3(void * block, const char * func, int linenumber) |
f3ebb786 JH |
892 | { |
893 | n_nonpool_blocks--; | |
65766f1b JH |
894 | internal_untainted_free(block, func, linenumber); |
895 | } | |
896 | ||
897 | /******************************************************************************/ | |
898 | static void | |
899 | internal_tainted_free(storeblock * block, const char * func, int linenumber) | |
900 | { | |
901 | #ifdef COMPILE_UTILITY | |
902 | func = func; | |
903 | linenumber = linenumber; | |
904 | #else | |
905 | DEBUG(D_memory) | |
906 | debug_printf("---Unmap %6p %-20s %4d\n", block, func, linenumber); | |
907 | #endif | |
908 | munmap((void *)block, block->length + ALIGNED_SIZEOF_STOREBLOCK); | |
f3ebb786 JH |
909 | } |
910 | ||
911 | /******************************************************************************/ | |
912 | /* Stats output on process exit */ | |
913 | void | |
914 | store_exit(void) | |
915 | { | |
916 | #ifndef COMPILE_UTILITY | |
917 | DEBUG(D_memory) | |
918 | { | |
919 | debug_printf("----Exit nonpool max: %3d kB in %d blocks\n", | |
920 | (max_nonpool_malloc+1023)/1024, max_nonpool_blocks); | |
921 | debug_printf("----Exit npools max: %3d kB\n", max_pool_malloc/1024); | |
922 | for (int i = 0; i < NPOOLS; i++) | |
923 | debug_printf("----Exit pool %d max: %3d kB in %d blocks\t%s %s\n", | |
924 | i, maxbytes[i]/1024, maxblocks[i], poolclass[i], pooluse[i]); | |
925 | } | |
926 | #endif | |
927 | } | |
928 | ||
059ec3d9 | 929 | /* End of store.c */ |