1 //===-- sanitizer_malloc_mac.inc --------------------------------*- C++ -*-===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file contains Mac-specific malloc interceptors and a custom zone
10 // implementation, which together replace the system allocator.
12 //===----------------------------------------------------------------------===//
14 #include "sanitizer_common/sanitizer_platform.h"
16 #error "This file should only be compiled on Darwin."
19 #include <AvailabilityMacros.h>
20 #include <CoreFoundation/CFBase.h>
22 #include <malloc/malloc.h>
25 #include "interception/interception.h"
26 #include "sanitizer_common/sanitizer_allocator_dlsym.h"
27 #include "sanitizer_common/sanitizer_mac.h"
29 // Similar code is used in Google Perftools,
30 // https://github.com/gperftools/gperftools.
32 namespace __sanitizer {
34 extern malloc_zone_t sanitizer_zone;
36 struct sanitizer_malloc_introspection_t : public malloc_introspection_t {
37 // IMPORTANT: Do not change the order, alignment, or types of these fields to
38 // maintain binary compatibility. You should only add fields to this struct.
40 // Used to track changes to the allocator that will affect
42 u64 allocator_enumeration_version;
47 u64 GetMallocZoneAllocatorEnumerationVersion() {
48 // This represents the current allocator ABI version.
49 // This field should be incremented every time the Allocator
50 // ABI changes in a way that breaks allocator enumeration.
54 } // namespace __sanitizer
56 INTERCEPTOR(malloc_zone_t *, malloc_create_zone,
57 vm_size_t start_size, unsigned zone_flags) {
58 COMMON_MALLOC_ENTER();
59 uptr page_size = GetPageSizeCached();
60 uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
61 COMMON_MALLOC_MEMALIGN(page_size, allocated_size);
62 malloc_zone_t *new_zone = (malloc_zone_t *)p;
63 internal_memcpy(new_zone, &sanitizer_zone, sizeof(sanitizer_zone));
64 new_zone->zone_name = NULL; // The name will be changed anyway.
65 // Prevent the client app from overwriting the zone contents.
66 // Library functions that need to modify the zone will set PROT_WRITE on it.
67 // This matches the behavior of malloc_create_zone() on OSX 10.7 and higher.
68 mprotect(new_zone, allocated_size, PROT_READ);
69 // We're explicitly *NOT* registering the zone.
73 INTERCEPTOR(void, malloc_destroy_zone, malloc_zone_t *zone) {
74 COMMON_MALLOC_ENTER();
75 // We don't need to do anything here. We're not registering new zones, so we
76 // don't to unregister. Just un-mprotect and free() the zone.
77 uptr page_size = GetPageSizeCached();
78 uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
79 mprotect(zone, allocated_size, PROT_READ | PROT_WRITE);
80 if (zone->zone_name) {
81 COMMON_MALLOC_FREE((void *)zone->zone_name);
83 COMMON_MALLOC_FREE(zone);
86 INTERCEPTOR(malloc_zone_t *, malloc_default_zone, void) {
87 COMMON_MALLOC_ENTER();
88 return &sanitizer_zone;
91 INTERCEPTOR(malloc_zone_t *, malloc_zone_from_ptr, const void *ptr) {
92 COMMON_MALLOC_ENTER();
93 size_t size = sanitizer_zone.size(&sanitizer_zone, ptr);
94 if (size) { // Claimed by sanitizer zone?
95 return &sanitizer_zone;
97 return REAL(malloc_zone_from_ptr)(ptr);
100 INTERCEPTOR(malloc_zone_t *, malloc_default_purgeable_zone, void) {
101 // FIXME: ASan should support purgeable allocations.
102 // https://github.com/google/sanitizers/issues/139
103 COMMON_MALLOC_ENTER();
104 return &sanitizer_zone;
107 INTERCEPTOR(void, malloc_make_purgeable, void *ptr) {
108 // FIXME: ASan should support purgeable allocations. Ignoring them is fine
110 COMMON_MALLOC_ENTER();
113 INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) {
114 // FIXME: ASan should support purgeable allocations. Ignoring them is fine
116 COMMON_MALLOC_ENTER();
117 // Must return 0 if the contents were not purged since the last call to
118 // malloc_make_purgeable().
122 INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) {
123 COMMON_MALLOC_ENTER();
124 InternalScopedString new_name;
125 if (name && zone->introspect == sanitizer_zone.introspect) {
126 new_name.AppendF(COMMON_MALLOC_ZONE_NAME "-%s", name);
127 name = new_name.data();
130 // Call the system malloc's implementation for both external and our zones,
131 // since that appropriately changes VM region protections on the zone.
132 REAL(malloc_set_zone_name)(zone, name);
135 INTERCEPTOR(void *, malloc, size_t size) {
136 COMMON_MALLOC_ENTER();
137 COMMON_MALLOC_MALLOC(size);
141 INTERCEPTOR(void, free, void *ptr) {
142 COMMON_MALLOC_ENTER();
144 COMMON_MALLOC_FREE(ptr);
147 INTERCEPTOR(void *, realloc, void *ptr, size_t size) {
148 COMMON_MALLOC_ENTER();
149 COMMON_MALLOC_REALLOC(ptr, size);
153 INTERCEPTOR(void *, calloc, size_t nmemb, size_t size) {
154 COMMON_MALLOC_ENTER();
155 COMMON_MALLOC_CALLOC(nmemb, size);
159 INTERCEPTOR(void *, valloc, size_t size) {
160 COMMON_MALLOC_ENTER();
161 COMMON_MALLOC_VALLOC(size);
165 INTERCEPTOR(size_t, malloc_good_size, size_t size) {
166 COMMON_MALLOC_ENTER();
167 return sanitizer_zone.introspect->good_size(&sanitizer_zone, size);
170 INTERCEPTOR(int, posix_memalign, void **memptr, size_t alignment, size_t size) {
171 COMMON_MALLOC_ENTER();
173 COMMON_MALLOC_POSIX_MEMALIGN(memptr, alignment, size);
179 // TODO(glider): the __sanitizer_mz_* functions should be united with the Linux
180 // wrappers, as they are basically copied from there.
182 SANITIZER_INTERFACE_ATTRIBUTE
183 size_t __sanitizer_mz_size(malloc_zone_t* zone, const void* ptr) {
184 COMMON_MALLOC_SIZE(ptr);
189 SANITIZER_INTERFACE_ATTRIBUTE
190 void *__sanitizer_mz_malloc(malloc_zone_t *zone, uptr size) {
191 COMMON_MALLOC_ENTER();
192 COMMON_MALLOC_MALLOC(size);
196 struct DlsymAlloc : public DlSymAllocator<DlsymAlloc> {
197 static bool UseImpl() { return !COMMON_MALLOC_SANITIZER_INITIALIZED; }
201 SANITIZER_INTERFACE_ATTRIBUTE
202 void *__sanitizer_mz_calloc(malloc_zone_t *zone, size_t nmemb, size_t size) {
203 if (DlsymAlloc::Use())
204 return DlsymAlloc::Callocate(nmemb, size);
205 COMMON_MALLOC_CALLOC(nmemb, size);
210 SANITIZER_INTERFACE_ATTRIBUTE
211 void *__sanitizer_mz_valloc(malloc_zone_t *zone, size_t size) {
212 COMMON_MALLOC_ENTER();
213 COMMON_MALLOC_VALLOC(size);
217 // TODO(glider): the allocation callbacks need to be refactored.
219 SANITIZER_INTERFACE_ATTRIBUTE
220 void __sanitizer_mz_free(malloc_zone_t *zone, void *ptr) {
222 if (DlsymAlloc::PointerIsMine(ptr))
223 return DlsymAlloc::Free(ptr);
224 COMMON_MALLOC_FREE(ptr);
227 #define GET_ZONE_FOR_PTR(ptr) \
228 malloc_zone_t *zone_ptr = WRAP(malloc_zone_from_ptr)(ptr); \
229 const char *zone_name = (zone_ptr == 0) ? 0 : zone_ptr->zone_name
232 SANITIZER_INTERFACE_ATTRIBUTE
233 void *__sanitizer_mz_realloc(malloc_zone_t *zone, void *ptr, size_t new_size) {
235 COMMON_MALLOC_MALLOC(new_size);
238 COMMON_MALLOC_SIZE(ptr);
240 COMMON_MALLOC_REALLOC(ptr, new_size);
243 // We can't recover from reallocating an unknown address, because
244 // this would require reading at most |new_size| bytes from
245 // potentially unaccessible memory.
246 GET_ZONE_FOR_PTR(ptr);
247 COMMON_MALLOC_REPORT_UNKNOWN_REALLOC(ptr, zone_ptr, zone_name);
254 SANITIZER_INTERFACE_ATTRIBUTE
255 void __sanitizer_mz_destroy(malloc_zone_t* zone) {
256 // A no-op -- we will not be destroyed!
257 Report("__sanitizer_mz_destroy() called -- ignoring\n");
261 SANITIZER_INTERFACE_ATTRIBUTE
262 void *__sanitizer_mz_memalign(malloc_zone_t *zone, size_t align, size_t size) {
263 COMMON_MALLOC_ENTER();
264 COMMON_MALLOC_MEMALIGN(align, size);
268 // This public API exists purely for testing purposes.
270 SANITIZER_INTERFACE_ATTRIBUTE
271 malloc_zone_t* __sanitizer_mz_default_zone() {
272 return &sanitizer_zone;
275 // This function is currently unused, and we build with -Werror.
277 void __sanitizer_mz_free_definite_size(
278 malloc_zone_t* zone, void *ptr, size_t size) {
279 // TODO(glider): check that |size| is valid.
284 #ifndef COMMON_MALLOC_HAS_ZONE_ENUMERATOR
285 #error "COMMON_MALLOC_HAS_ZONE_ENUMERATOR must be defined"
287 static_assert((COMMON_MALLOC_HAS_ZONE_ENUMERATOR) == 0 ||
288 (COMMON_MALLOC_HAS_ZONE_ENUMERATOR) == 1,
289 "COMMON_MALLOC_HAS_ZONE_ENUMERATOR must be 0 or 1");
291 #if COMMON_MALLOC_HAS_ZONE_ENUMERATOR
292 // Forward declare and expect the implementation to provided by
294 kern_return_t mi_enumerator(task_t task, void *, unsigned type_mask,
295 vm_address_t zone_address, memory_reader_t reader,
296 vm_range_recorder_t recorder);
298 // Provide stub implementation that fails.
299 kern_return_t mi_enumerator(task_t task, void *, unsigned type_mask,
300 vm_address_t zone_address, memory_reader_t reader,
301 vm_range_recorder_t recorder) {
307 #ifndef COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT
308 #error "COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT must be defined"
310 static_assert((COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT) == 0 ||
311 (COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT) == 1,
312 "COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT must be 0 or 1");
313 #if COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT
314 // Forward declare and expect the implementation to provided by
317 sanitizer_malloc_introspection_t *mi);
320 sanitizer_malloc_introspection_t *mi) {
321 // Just zero initialize the fields.
322 mi->allocator_ptr = 0;
323 mi->allocator_size = 0;
327 size_t mi_good_size(malloc_zone_t *zone, size_t size) {
328 // I think it's always safe to return size, but we maybe could do better.
332 boolean_t mi_check(malloc_zone_t *zone) {
336 void mi_print(malloc_zone_t *zone, boolean_t verbose) {
340 void mi_log(malloc_zone_t *zone, void *address) {
341 // I don't think we support anything like this
344 void mi_force_lock(malloc_zone_t *zone) {
345 COMMON_MALLOC_FORCE_LOCK();
348 void mi_force_unlock(malloc_zone_t *zone) {
349 COMMON_MALLOC_FORCE_UNLOCK();
352 void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
353 COMMON_MALLOC_FILL_STATS(zone, stats);
356 boolean_t mi_zone_locked(malloc_zone_t *zone) {
361 } // unnamed namespace
363 namespace COMMON_MALLOC_NAMESPACE {
365 void InitMallocZoneFields() {
366 static sanitizer_malloc_introspection_t sanitizer_zone_introspection;
367 // Ok to use internal_memset, these places are not performance-critical.
368 internal_memset(&sanitizer_zone_introspection, 0,
369 sizeof(sanitizer_zone_introspection));
371 sanitizer_zone_introspection.enumerator = &mi_enumerator;
372 sanitizer_zone_introspection.good_size = &mi_good_size;
373 sanitizer_zone_introspection.check = &mi_check;
374 sanitizer_zone_introspection.print = &mi_print;
375 sanitizer_zone_introspection.log = &mi_log;
376 sanitizer_zone_introspection.force_lock = &mi_force_lock;
377 sanitizer_zone_introspection.force_unlock = &mi_force_unlock;
378 sanitizer_zone_introspection.statistics = &mi_statistics;
379 sanitizer_zone_introspection.zone_locked = &mi_zone_locked;
381 // Set current allocator enumeration version.
382 sanitizer_zone_introspection.allocator_enumeration_version =
383 GetMallocZoneAllocatorEnumerationVersion();
385 // Perform any sanitizer specific initialization.
386 mi_extra_init(&sanitizer_zone_introspection);
388 internal_memset(&sanitizer_zone, 0, sizeof(malloc_zone_t));
390 // Use version 6 for OSX >= 10.6.
391 sanitizer_zone.version = 6;
392 sanitizer_zone.zone_name = COMMON_MALLOC_ZONE_NAME;
393 sanitizer_zone.size = &__sanitizer_mz_size;
394 sanitizer_zone.malloc = &__sanitizer_mz_malloc;
395 sanitizer_zone.calloc = &__sanitizer_mz_calloc;
396 sanitizer_zone.valloc = &__sanitizer_mz_valloc;
397 sanitizer_zone.free = &__sanitizer_mz_free;
398 sanitizer_zone.realloc = &__sanitizer_mz_realloc;
399 sanitizer_zone.destroy = &__sanitizer_mz_destroy;
400 sanitizer_zone.batch_malloc = 0;
401 sanitizer_zone.batch_free = 0;
402 sanitizer_zone.free_definite_size = 0;
403 sanitizer_zone.memalign = &__sanitizer_mz_memalign;
404 sanitizer_zone.introspect = &sanitizer_zone_introspection;
407 void ReplaceSystemMalloc() {
408 InitMallocZoneFields();
410 // Register the zone.
411 malloc_zone_register(&sanitizer_zone);
414 } // namespace COMMON_MALLOC_NAMESPACE