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_mac.h"
28 // Similar code is used in Google Perftools,
29 // https://github.com/gperftools/gperftools.
31 namespace __sanitizer {
33 extern malloc_zone_t sanitizer_zone;
35 struct sanitizer_malloc_introspection_t : public malloc_introspection_t {
36 // IMPORTANT: Do not change the order, alignment, or types of these fields to
37 // maintain binary compatibility. You should only add fields to this struct.
39 // Used to track changes to the allocator that will affect
41 u64 allocator_enumeration_version;
46 u64 GetMallocZoneAllocatorEnumerationVersion() {
47 // This represents the current allocator ABI version.
48 // This field should be incremented every time the Allocator
49 // ABI changes in a way that breaks allocator enumeration.
53 } // namespace __sanitizer
55 INTERCEPTOR(malloc_zone_t *, malloc_create_zone,
56 vm_size_t start_size, unsigned zone_flags) {
57 COMMON_MALLOC_ENTER();
58 uptr page_size = GetPageSizeCached();
59 uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
60 COMMON_MALLOC_MEMALIGN(page_size, allocated_size);
61 malloc_zone_t *new_zone = (malloc_zone_t *)p;
62 internal_memcpy(new_zone, &sanitizer_zone, sizeof(sanitizer_zone));
63 new_zone->zone_name = NULL; // The name will be changed anyway.
64 if (GetMacosVersion() >= MACOS_VERSION_LION) {
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);
70 // We're explicitly *NOT* registering the zone.
74 INTERCEPTOR(void, malloc_destroy_zone, malloc_zone_t *zone) {
75 COMMON_MALLOC_ENTER();
76 // We don't need to do anything here. We're not registering new zones, so we
77 // don't to unregister. Just un-mprotect and free() the zone.
78 if (GetMacosVersion() >= MACOS_VERSION_LION) {
79 uptr page_size = GetPageSizeCached();
80 uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
81 mprotect(zone, allocated_size, PROT_READ | PROT_WRITE);
83 if (zone->zone_name) {
84 COMMON_MALLOC_FREE((void *)zone->zone_name);
86 COMMON_MALLOC_FREE(zone);
89 INTERCEPTOR(malloc_zone_t *, malloc_default_zone, void) {
90 COMMON_MALLOC_ENTER();
91 return &sanitizer_zone;
94 INTERCEPTOR(malloc_zone_t *, malloc_zone_from_ptr, const void *ptr) {
95 COMMON_MALLOC_ENTER();
96 size_t size = sanitizer_zone.size(&sanitizer_zone, ptr);
97 if (size) { // Claimed by sanitizer zone?
98 return &sanitizer_zone;
100 return REAL(malloc_zone_from_ptr)(ptr);
103 INTERCEPTOR(malloc_zone_t *, malloc_default_purgeable_zone, void) {
104 // FIXME: ASan should support purgeable allocations.
105 // https://github.com/google/sanitizers/issues/139
106 COMMON_MALLOC_ENTER();
107 return &sanitizer_zone;
110 INTERCEPTOR(void, malloc_make_purgeable, void *ptr) {
111 // FIXME: ASan should support purgeable allocations. Ignoring them is fine
113 COMMON_MALLOC_ENTER();
116 INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) {
117 // FIXME: ASan should support purgeable allocations. Ignoring them is fine
119 COMMON_MALLOC_ENTER();
120 // Must return 0 if the contents were not purged since the last call to
121 // malloc_make_purgeable().
125 INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) {
126 COMMON_MALLOC_ENTER();
127 // Allocate |sizeof(COMMON_MALLOC_ZONE_NAME "-") + internal_strlen(name)|
130 sizeof(COMMON_MALLOC_ZONE_NAME "-") + (name ? internal_strlen(name) : 0);
131 InternalScopedString new_name(buflen);
132 if (name && zone->introspect == sanitizer_zone.introspect) {
133 new_name.append(COMMON_MALLOC_ZONE_NAME "-%s", name);
134 name = new_name.data();
137 // Call the system malloc's implementation for both external and our zones,
138 // since that appropriately changes VM region protections on the zone.
139 REAL(malloc_set_zone_name)(zone, name);
142 INTERCEPTOR(void *, malloc, size_t size) {
143 COMMON_MALLOC_ENTER();
144 COMMON_MALLOC_MALLOC(size);
148 INTERCEPTOR(void, free, void *ptr) {
149 COMMON_MALLOC_ENTER();
151 COMMON_MALLOC_FREE(ptr);
154 INTERCEPTOR(void *, realloc, void *ptr, size_t size) {
155 COMMON_MALLOC_ENTER();
156 COMMON_MALLOC_REALLOC(ptr, size);
160 INTERCEPTOR(void *, calloc, size_t nmemb, size_t size) {
161 COMMON_MALLOC_ENTER();
162 COMMON_MALLOC_CALLOC(nmemb, size);
166 INTERCEPTOR(void *, valloc, size_t size) {
167 COMMON_MALLOC_ENTER();
168 COMMON_MALLOC_VALLOC(size);
172 INTERCEPTOR(size_t, malloc_good_size, size_t size) {
173 COMMON_MALLOC_ENTER();
174 return sanitizer_zone.introspect->good_size(&sanitizer_zone, size);
177 INTERCEPTOR(int, posix_memalign, void **memptr, size_t alignment, size_t size) {
178 COMMON_MALLOC_ENTER();
180 COMMON_MALLOC_POSIX_MEMALIGN(memptr, alignment, size);
186 // TODO(glider): the __sanitizer_mz_* functions should be united with the Linux
187 // wrappers, as they are basically copied from there.
189 SANITIZER_INTERFACE_ATTRIBUTE
190 size_t __sanitizer_mz_size(malloc_zone_t* zone, const void* ptr) {
191 COMMON_MALLOC_SIZE(ptr);
196 SANITIZER_INTERFACE_ATTRIBUTE
197 void *__sanitizer_mz_malloc(malloc_zone_t *zone, uptr size) {
198 COMMON_MALLOC_ENTER();
199 COMMON_MALLOC_MALLOC(size);
204 SANITIZER_INTERFACE_ATTRIBUTE
205 void *__sanitizer_mz_calloc(malloc_zone_t *zone, size_t nmemb, size_t size) {
206 if (UNLIKELY(!COMMON_MALLOC_SANITIZER_INITIALIZED)) {
207 // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
208 const size_t kCallocPoolSize = 1024;
209 static uptr calloc_memory_for_dlsym[kCallocPoolSize];
210 static size_t allocated;
211 size_t size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize;
212 void *mem = (void*)&calloc_memory_for_dlsym[allocated];
213 allocated += size_in_words;
214 CHECK(allocated < kCallocPoolSize);
217 COMMON_MALLOC_CALLOC(nmemb, size);
222 SANITIZER_INTERFACE_ATTRIBUTE
223 void *__sanitizer_mz_valloc(malloc_zone_t *zone, size_t size) {
224 COMMON_MALLOC_ENTER();
225 COMMON_MALLOC_VALLOC(size);
229 // TODO(glider): the allocation callbacks need to be refactored.
231 SANITIZER_INTERFACE_ATTRIBUTE
232 void __sanitizer_mz_free(malloc_zone_t *zone, void *ptr) {
234 COMMON_MALLOC_FREE(ptr);
237 #define GET_ZONE_FOR_PTR(ptr) \
238 malloc_zone_t *zone_ptr = WRAP(malloc_zone_from_ptr)(ptr); \
239 const char *zone_name = (zone_ptr == 0) ? 0 : zone_ptr->zone_name
242 SANITIZER_INTERFACE_ATTRIBUTE
243 void *__sanitizer_mz_realloc(malloc_zone_t *zone, void *ptr, size_t new_size) {
245 COMMON_MALLOC_MALLOC(new_size);
248 COMMON_MALLOC_SIZE(ptr);
250 COMMON_MALLOC_REALLOC(ptr, new_size);
253 // We can't recover from reallocating an unknown address, because
254 // this would require reading at most |new_size| bytes from
255 // potentially unaccessible memory.
256 GET_ZONE_FOR_PTR(ptr);
257 COMMON_MALLOC_REPORT_UNKNOWN_REALLOC(ptr, zone_ptr, zone_name);
264 SANITIZER_INTERFACE_ATTRIBUTE
265 void __sanitizer_mz_destroy(malloc_zone_t* zone) {
266 // A no-op -- we will not be destroyed!
267 Report("__sanitizer_mz_destroy() called -- ignoring\n");
271 SANITIZER_INTERFACE_ATTRIBUTE
272 void *__sanitizer_mz_memalign(malloc_zone_t *zone, size_t align, size_t size) {
273 COMMON_MALLOC_ENTER();
274 COMMON_MALLOC_MEMALIGN(align, size);
278 // This public API exists purely for testing purposes.
280 SANITIZER_INTERFACE_ATTRIBUTE
281 malloc_zone_t* __sanitizer_mz_default_zone() {
282 return &sanitizer_zone;
285 // This function is currently unused, and we build with -Werror.
287 void __sanitizer_mz_free_definite_size(
288 malloc_zone_t* zone, void *ptr, size_t size) {
289 // TODO(glider): check that |size| is valid.
294 #ifndef COMMON_MALLOC_HAS_ZONE_ENUMERATOR
295 #error "COMMON_MALLOC_HAS_ZONE_ENUMERATOR must be defined"
297 static_assert((COMMON_MALLOC_HAS_ZONE_ENUMERATOR) == 0 ||
298 (COMMON_MALLOC_HAS_ZONE_ENUMERATOR) == 1,
299 "COMMON_MALLOC_HAS_ZONE_ENUMERATOR must be 0 or 1");
301 #if COMMON_MALLOC_HAS_ZONE_ENUMERATOR
302 // Forward declare and expect the implementation to provided by
304 kern_return_t mi_enumerator(task_t task, void *, unsigned type_mask,
305 vm_address_t zone_address, memory_reader_t reader,
306 vm_range_recorder_t recorder);
308 // Provide stub implementation that fails.
309 kern_return_t mi_enumerator(task_t task, void *, unsigned type_mask,
310 vm_address_t zone_address, memory_reader_t reader,
311 vm_range_recorder_t recorder) {
317 #ifndef COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT
318 #error "COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT must be defined"
320 static_assert((COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT) == 0 ||
321 (COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT) == 1,
322 "COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT must be 0 or 1");
323 #if COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT
324 // Forward declare and expect the implementation to provided by
327 sanitizer_malloc_introspection_t *mi);
330 sanitizer_malloc_introspection_t *mi) {
331 // Just zero initialize the fields.
332 mi->allocator_ptr = 0;
333 mi->allocator_size = 0;
337 size_t mi_good_size(malloc_zone_t *zone, size_t size) {
338 // I think it's always safe to return size, but we maybe could do better.
342 boolean_t mi_check(malloc_zone_t *zone) {
346 void mi_print(malloc_zone_t *zone, boolean_t verbose) {
350 void mi_log(malloc_zone_t *zone, void *address) {
351 // I don't think we support anything like this
354 void mi_force_lock(malloc_zone_t *zone) {
355 COMMON_MALLOC_FORCE_LOCK();
358 void mi_force_unlock(malloc_zone_t *zone) {
359 COMMON_MALLOC_FORCE_UNLOCK();
362 void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
363 COMMON_MALLOC_FILL_STATS(zone, stats);
366 boolean_t mi_zone_locked(malloc_zone_t *zone) {
371 } // unnamed namespace
373 namespace COMMON_MALLOC_NAMESPACE {
375 void InitMallocZoneFields() {
376 static sanitizer_malloc_introspection_t sanitizer_zone_introspection;
377 // Ok to use internal_memset, these places are not performance-critical.
378 internal_memset(&sanitizer_zone_introspection, 0,
379 sizeof(sanitizer_zone_introspection));
381 sanitizer_zone_introspection.enumerator = &mi_enumerator;
382 sanitizer_zone_introspection.good_size = &mi_good_size;
383 sanitizer_zone_introspection.check = &mi_check;
384 sanitizer_zone_introspection.print = &mi_print;
385 sanitizer_zone_introspection.log = &mi_log;
386 sanitizer_zone_introspection.force_lock = &mi_force_lock;
387 sanitizer_zone_introspection.force_unlock = &mi_force_unlock;
388 sanitizer_zone_introspection.statistics = &mi_statistics;
389 sanitizer_zone_introspection.zone_locked = &mi_zone_locked;
391 // Set current allocator enumeration version.
392 sanitizer_zone_introspection.allocator_enumeration_version =
393 GetMallocZoneAllocatorEnumerationVersion();
395 // Perform any sanitizer specific initialization.
396 mi_extra_init(&sanitizer_zone_introspection);
398 internal_memset(&sanitizer_zone, 0, sizeof(malloc_zone_t));
400 // Use version 6 for OSX >= 10.6.
401 sanitizer_zone.version = 6;
402 sanitizer_zone.zone_name = COMMON_MALLOC_ZONE_NAME;
403 sanitizer_zone.size = &__sanitizer_mz_size;
404 sanitizer_zone.malloc = &__sanitizer_mz_malloc;
405 sanitizer_zone.calloc = &__sanitizer_mz_calloc;
406 sanitizer_zone.valloc = &__sanitizer_mz_valloc;
407 sanitizer_zone.free = &__sanitizer_mz_free;
408 sanitizer_zone.realloc = &__sanitizer_mz_realloc;
409 sanitizer_zone.destroy = &__sanitizer_mz_destroy;
410 sanitizer_zone.batch_malloc = 0;
411 sanitizer_zone.batch_free = 0;
412 sanitizer_zone.free_definite_size = 0;
413 sanitizer_zone.memalign = &__sanitizer_mz_memalign;
414 sanitizer_zone.introspect = &sanitizer_zone_introspection;
417 void ReplaceSystemMalloc() {
418 InitMallocZoneFields();
420 // Register the zone.
421 malloc_zone_register(&sanitizer_zone);
424 } // namespace COMMON_MALLOC_NAMESPACE