1 //===-- sanitizer_malloc_mac.inc --------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains Mac-specific malloc interceptors and a custom zone
11 // implementation, which together replace the system allocator.
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_common/sanitizer_platform.h"
17 #error "This file should only be compiled on Darwin."
20 #include <AvailabilityMacros.h>
21 #include <CoreFoundation/CFBase.h>
23 #include <malloc/malloc.h>
26 #include "interception/interception.h"
27 #include "sanitizer_common/sanitizer_mac.h"
29 // Similar code is used in Google Perftools,
30 // https://github.com/gperftools/gperftools.
32 static malloc_zone_t sanitizer_zone;
34 INTERCEPTOR(malloc_zone_t *, malloc_create_zone,
35 vm_size_t start_size, unsigned zone_flags) {
36 COMMON_MALLOC_ENTER();
37 uptr page_size = GetPageSizeCached();
38 uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
39 COMMON_MALLOC_MEMALIGN(page_size, allocated_size);
40 malloc_zone_t *new_zone = (malloc_zone_t *)p;
41 internal_memcpy(new_zone, &sanitizer_zone, sizeof(sanitizer_zone));
42 new_zone->zone_name = NULL; // The name will be changed anyway.
43 if (GetMacosVersion() >= MACOS_VERSION_LION) {
44 // Prevent the client app from overwriting the zone contents.
45 // Library functions that need to modify the zone will set PROT_WRITE on it.
46 // This matches the behavior of malloc_create_zone() on OSX 10.7 and higher.
47 mprotect(new_zone, allocated_size, PROT_READ);
49 // We're explicitly *NOT* registering the zone.
53 INTERCEPTOR(void, malloc_destroy_zone, malloc_zone_t *zone) {
54 COMMON_MALLOC_ENTER();
55 // We don't need to do anything here. We're not registering new zones, so we
56 // don't to unregister. Just un-mprotect and free() the zone.
57 if (GetMacosVersion() >= MACOS_VERSION_LION) {
58 uptr page_size = GetPageSizeCached();
59 uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
60 mprotect(zone, allocated_size, PROT_READ | PROT_WRITE);
62 COMMON_MALLOC_FREE(zone);
65 extern unsigned malloc_num_zones;
66 extern malloc_zone_t **malloc_zones;
68 // We need to make sure that sanitizer_zone is registered as malloc_zones[0]. If
69 // libmalloc tries to set up a different zone as malloc_zones[0], it will call
70 // mprotect(malloc_zones, ..., PROT_READ). This interceptor will catch that and
71 // make sure we are still the first (default) zone.
72 INTERCEPTOR(int, mprotect, void *addr, size_t len, int prot) {
73 if (addr == malloc_zones && prot == PROT_READ) {
74 if (malloc_num_zones > 1 && malloc_zones[0] != &sanitizer_zone) {
75 for (unsigned i = 1; i < malloc_num_zones; i++) {
76 if (malloc_zones[i] == &sanitizer_zone) {
77 // Swap malloc_zones[0] and malloc_zones[i].
78 malloc_zones[i] = malloc_zones[0];
79 malloc_zones[0] = &sanitizer_zone;
85 return REAL(mprotect)(addr, len, prot);
88 INTERCEPTOR(malloc_zone_t *, malloc_default_zone, void) {
89 COMMON_MALLOC_ENTER();
90 return &sanitizer_zone;
93 INTERCEPTOR(malloc_zone_t *, malloc_default_purgeable_zone, void) {
94 // FIXME: ASan should support purgeable allocations.
95 // https://github.com/google/sanitizers/issues/139
96 COMMON_MALLOC_ENTER();
97 return &sanitizer_zone;
100 INTERCEPTOR(void, malloc_make_purgeable, void *ptr) {
101 // FIXME: ASan should support purgeable allocations. Ignoring them is fine
103 COMMON_MALLOC_ENTER();
106 INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) {
107 // FIXME: ASan should support purgeable allocations. Ignoring them is fine
109 COMMON_MALLOC_ENTER();
110 // Must return 0 if the contents were not purged since the last call to
111 // malloc_make_purgeable().
115 INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) {
116 COMMON_MALLOC_ENTER();
117 // Allocate |sizeof(COMMON_MALLOC_ZONE_NAME "-") + internal_strlen(name)|
120 sizeof(COMMON_MALLOC_ZONE_NAME "-") + (name ? internal_strlen(name) : 0);
121 InternalScopedString new_name(buflen);
122 if (name && zone->introspect == sanitizer_zone.introspect) {
123 new_name.append(COMMON_MALLOC_ZONE_NAME "-%s", name);
124 name = new_name.data();
127 // Call the system malloc's implementation for both external and our zones,
128 // since that appropriately changes VM region protections on the zone.
129 REAL(malloc_set_zone_name)(zone, name);
132 INTERCEPTOR(void *, malloc, size_t size) {
133 COMMON_MALLOC_ENTER();
134 COMMON_MALLOC_MALLOC(size);
138 INTERCEPTOR(void, free, void *ptr) {
139 COMMON_MALLOC_ENTER();
141 COMMON_MALLOC_FREE(ptr);
144 INTERCEPTOR(void *, realloc, void *ptr, size_t size) {
145 COMMON_MALLOC_ENTER();
146 COMMON_MALLOC_REALLOC(ptr, size);
150 INTERCEPTOR(void *, calloc, size_t nmemb, size_t size) {
151 COMMON_MALLOC_ENTER();
152 COMMON_MALLOC_CALLOC(nmemb, size);
156 INTERCEPTOR(void *, valloc, size_t size) {
157 COMMON_MALLOC_ENTER();
158 COMMON_MALLOC_VALLOC(size);
162 INTERCEPTOR(size_t, malloc_good_size, size_t size) {
163 COMMON_MALLOC_ENTER();
164 return sanitizer_zone.introspect->good_size(&sanitizer_zone, size);
167 INTERCEPTOR(int, posix_memalign, void **memptr, size_t alignment, size_t size) {
168 COMMON_MALLOC_ENTER();
170 COMMON_MALLOC_MEMALIGN(alignment, size);
180 // TODO(glider): the __sanitizer_mz_* functions should be united with the Linux
181 // wrappers, as they are basically copied from there.
183 SANITIZER_INTERFACE_ATTRIBUTE
184 size_t __sanitizer_mz_size(malloc_zone_t* zone, const void* ptr) {
185 COMMON_MALLOC_SIZE(ptr);
190 SANITIZER_INTERFACE_ATTRIBUTE
191 void *__sanitizer_mz_malloc(malloc_zone_t *zone, uptr size) {
192 COMMON_MALLOC_ENTER();
193 COMMON_MALLOC_MALLOC(size);
198 SANITIZER_INTERFACE_ATTRIBUTE
199 void *__sanitizer_mz_calloc(malloc_zone_t *zone, size_t nmemb, size_t size) {
200 if (UNLIKELY(!COMMON_MALLOC_SANITIZER_INITIALIZED)) {
201 // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
202 const size_t kCallocPoolSize = 1024;
203 static uptr calloc_memory_for_dlsym[kCallocPoolSize];
204 static size_t allocated;
205 size_t size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize;
206 void *mem = (void*)&calloc_memory_for_dlsym[allocated];
207 allocated += size_in_words;
208 CHECK(allocated < kCallocPoolSize);
211 COMMON_MALLOC_CALLOC(nmemb, size);
216 SANITIZER_INTERFACE_ATTRIBUTE
217 void *__sanitizer_mz_valloc(malloc_zone_t *zone, size_t size) {
218 COMMON_MALLOC_ENTER();
219 COMMON_MALLOC_VALLOC(size);
223 // TODO(glider): the allocation callbacks need to be refactored.
225 SANITIZER_INTERFACE_ATTRIBUTE
226 void __sanitizer_mz_free(malloc_zone_t *zone, void *ptr) {
228 COMMON_MALLOC_FREE(ptr);
231 #define GET_ZONE_FOR_PTR(ptr) \
232 malloc_zone_t *zone_ptr = malloc_zone_from_ptr(ptr); \
233 const char *zone_name = (zone_ptr == 0) ? 0 : zone_ptr->zone_name
236 SANITIZER_INTERFACE_ATTRIBUTE
237 void *__sanitizer_mz_realloc(malloc_zone_t *zone, void *ptr, size_t new_size) {
239 COMMON_MALLOC_MALLOC(new_size);
242 COMMON_MALLOC_SIZE(ptr);
244 COMMON_MALLOC_REALLOC(ptr, new_size);
247 // We can't recover from reallocating an unknown address, because
248 // this would require reading at most |new_size| bytes from
249 // potentially unaccessible memory.
250 GET_ZONE_FOR_PTR(ptr);
251 COMMON_MALLOC_REPORT_UNKNOWN_REALLOC(ptr, zone_ptr, zone_name);
258 SANITIZER_INTERFACE_ATTRIBUTE
259 void __sanitizer_mz_destroy(malloc_zone_t* zone) {
260 // A no-op -- we will not be destroyed!
261 Report("__sanitizer_mz_destroy() called -- ignoring\n");
265 SANITIZER_INTERFACE_ATTRIBUTE
266 void *__sanitizer_mz_memalign(malloc_zone_t *zone, size_t align, size_t size) {
267 COMMON_MALLOC_ENTER();
268 COMMON_MALLOC_MEMALIGN(align, size);
272 // This function is currently unused, and we build with -Werror.
274 void __sanitizer_mz_free_definite_size(
275 malloc_zone_t* zone, void *ptr, size_t size) {
276 // TODO(glider): check that |size| is valid.
281 kern_return_t mi_enumerator(task_t task, void *,
282 unsigned type_mask, vm_address_t zone_address,
283 memory_reader_t reader,
284 vm_range_recorder_t recorder) {
285 // Should enumerate all the pointers we have. Seems like a lot of work.
289 size_t mi_good_size(malloc_zone_t *zone, size_t size) {
290 // I think it's always safe to return size, but we maybe could do better.
294 boolean_t mi_check(malloc_zone_t *zone) {
298 void mi_print(malloc_zone_t *zone, boolean_t verbose) {
302 void mi_log(malloc_zone_t *zone, void *address) {
303 // I don't think we support anything like this
306 void mi_force_lock(malloc_zone_t *zone) {
307 COMMON_MALLOC_FORCE_LOCK();
310 void mi_force_unlock(malloc_zone_t *zone) {
311 COMMON_MALLOC_FORCE_UNLOCK();
314 void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
315 COMMON_MALLOC_FILL_STATS(zone, stats);
318 boolean_t mi_zone_locked(malloc_zone_t *zone) {
323 } // unnamed namespace
325 namespace COMMON_MALLOC_NAMESPACE {
327 void ReplaceSystemMalloc() {
328 static malloc_introspection_t sanitizer_zone_introspection;
329 // Ok to use internal_memset, these places are not performance-critical.
330 internal_memset(&sanitizer_zone_introspection, 0,
331 sizeof(sanitizer_zone_introspection));
333 sanitizer_zone_introspection.enumerator = &mi_enumerator;
334 sanitizer_zone_introspection.good_size = &mi_good_size;
335 sanitizer_zone_introspection.check = &mi_check;
336 sanitizer_zone_introspection.print = &mi_print;
337 sanitizer_zone_introspection.log = &mi_log;
338 sanitizer_zone_introspection.force_lock = &mi_force_lock;
339 sanitizer_zone_introspection.force_unlock = &mi_force_unlock;
340 sanitizer_zone_introspection.statistics = &mi_statistics;
341 sanitizer_zone_introspection.zone_locked = &mi_zone_locked;
343 internal_memset(&sanitizer_zone, 0, sizeof(malloc_zone_t));
345 // Use version 6 for OSX >= 10.6.
346 sanitizer_zone.version = 6;
347 sanitizer_zone.zone_name = COMMON_MALLOC_ZONE_NAME;
348 sanitizer_zone.size = &__sanitizer_mz_size;
349 sanitizer_zone.malloc = &__sanitizer_mz_malloc;
350 sanitizer_zone.calloc = &__sanitizer_mz_calloc;
351 sanitizer_zone.valloc = &__sanitizer_mz_valloc;
352 sanitizer_zone.free = &__sanitizer_mz_free;
353 sanitizer_zone.realloc = &__sanitizer_mz_realloc;
354 sanitizer_zone.destroy = &__sanitizer_mz_destroy;
355 sanitizer_zone.batch_malloc = 0;
356 sanitizer_zone.batch_free = 0;
357 sanitizer_zone.free_definite_size = 0;
358 sanitizer_zone.memalign = &__sanitizer_mz_memalign;
359 sanitizer_zone.introspect = &sanitizer_zone_introspection;
361 // Register the zone.
362 malloc_zone_register(&sanitizer_zone);
365 } // namespace COMMON_MALLOC_NAMESPACE