libsanitizer/sanitizer_common/sanitizer_malloc_mac.inc

   1 //===-- sanitizer_malloc_mac.inc --------------------------------*- C++ -*-===//
   2 //
   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
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains Mac-specific malloc interceptors and a custom zone
  10 // implementation, which together replace the system allocator.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "sanitizer_common/sanitizer_platform.h"
  15 #if !SANITIZER_MAC
  16 #error "This file should only be compiled on Darwin."
  17 #endif
  18
  19 #include <AvailabilityMacros.h>
  20 #include <CoreFoundation/CFBase.h>
  21 #include <dlfcn.h>
  22 #include <malloc/malloc.h>
  23 #include <sys/mman.h>
  24
  25 #include "interception/interception.h"
  26 #include "sanitizer_common/sanitizer_mac.h"
  27
  28 // Similar code is used in Google Perftools,
  29 // https://github.com/gperftools/gperftools.
  30
  31 namespace __sanitizer {
  32
  33 extern malloc_zone_t sanitizer_zone;
  34
  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.
  38
  39   // Used to track changes to the allocator that will affect
  40   // zone enumeration.
  41   u64 allocator_enumeration_version;
  42   uptr allocator_ptr;
  43   uptr allocator_size;
  44 };
  45
  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.
  50   return 0;
  51 }
  52
  53 }  // namespace __sanitizer
  54
  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   // Prevent the client app from overwriting the zone contents.
  65   // Library functions that need to modify the zone will set PROT_WRITE on it.
  66   // This matches the behavior of malloc_create_zone() on OSX 10.7 and higher.
  67   mprotect(new_zone, allocated_size, PROT_READ);
  68   // We're explicitly *NOT* registering the zone.
  69   return new_zone;
  70 }
  71
  72 INTERCEPTOR(void, malloc_destroy_zone, malloc_zone_t *zone) {
  73   COMMON_MALLOC_ENTER();
  74   // We don't need to do anything here.  We're not registering new zones, so we
  75   // don't to unregister.  Just un-mprotect and free() the zone.
  76   uptr page_size = GetPageSizeCached();
  77   uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
  78   mprotect(zone, allocated_size, PROT_READ | PROT_WRITE);
  79   if (zone->zone_name) {
  80     COMMON_MALLOC_FREE((void *)zone->zone_name);
  81   }
  82   COMMON_MALLOC_FREE(zone);
  83 }
  84
  85 INTERCEPTOR(malloc_zone_t *, malloc_default_zone, void) {
  86   COMMON_MALLOC_ENTER();
  87   return &sanitizer_zone;
  88 }
  89
  90 INTERCEPTOR(malloc_zone_t *, malloc_zone_from_ptr, const void *ptr) {
  91   COMMON_MALLOC_ENTER();
  92   size_t size = sanitizer_zone.size(&sanitizer_zone, ptr);
  93   if (size) { // Claimed by sanitizer zone?
  94     return &sanitizer_zone;
  95   }
  96   return REAL(malloc_zone_from_ptr)(ptr);
  97 }
  98
  99 INTERCEPTOR(malloc_zone_t *, malloc_default_purgeable_zone, void) {
 100   // FIXME: ASan should support purgeable allocations.
 101   // https://github.com/google/sanitizers/issues/139
 102   COMMON_MALLOC_ENTER();
 103   return &sanitizer_zone;
 104 }
 105
 106 INTERCEPTOR(void, malloc_make_purgeable, void *ptr) {
 107   // FIXME: ASan should support purgeable allocations. Ignoring them is fine
 108   // for now.
 109   COMMON_MALLOC_ENTER();
 110 }
 111
 112 INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) {
 113   // FIXME: ASan should support purgeable allocations. Ignoring them is fine
 114   // for now.
 115   COMMON_MALLOC_ENTER();
 116   // Must return 0 if the contents were not purged since the last call to
 117   // malloc_make_purgeable().
 118   return 0;
 119 }
 120
 121 INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) {
 122   COMMON_MALLOC_ENTER();
 123   // Allocate |sizeof(COMMON_MALLOC_ZONE_NAME "-") + internal_strlen(name)|
 124   // bytes.
 125   size_t buflen =
 126       sizeof(COMMON_MALLOC_ZONE_NAME "-") + (name ? internal_strlen(name) : 0);
 127   InternalScopedString new_name(buflen);
 128   if (name && zone->introspect == sanitizer_zone.introspect) {
 129     new_name.append(COMMON_MALLOC_ZONE_NAME "-%s", name);
 130     name = new_name.data();
 131   }
 132
 133   // Call the system malloc's implementation for both external and our zones,
 134   // since that appropriately changes VM region protections on the zone.
 135   REAL(malloc_set_zone_name)(zone, name);
 136 }
 137
 138 INTERCEPTOR(void *, malloc, size_t size) {
 139   COMMON_MALLOC_ENTER();
 140   COMMON_MALLOC_MALLOC(size);
 141   return p;
 142 }
 143
 144 INTERCEPTOR(void, free, void *ptr) {
 145   COMMON_MALLOC_ENTER();
 146   if (!ptr) return;
 147   COMMON_MALLOC_FREE(ptr);
 148 }
 149
 150 INTERCEPTOR(void *, realloc, void *ptr, size_t size) {
 151   COMMON_MALLOC_ENTER();
 152   COMMON_MALLOC_REALLOC(ptr, size);
 153   return p;
 154 }
 155
 156 INTERCEPTOR(void *, calloc, size_t nmemb, size_t size) {
 157   COMMON_MALLOC_ENTER();
 158   COMMON_MALLOC_CALLOC(nmemb, size);
 159   return p;
 160 }
 161
 162 INTERCEPTOR(void *, valloc, size_t size) {
 163   COMMON_MALLOC_ENTER();
 164   COMMON_MALLOC_VALLOC(size);
 165   return p;
 166 }
 167
 168 INTERCEPTOR(size_t, malloc_good_size, size_t size) {
 169   COMMON_MALLOC_ENTER();
 170   return sanitizer_zone.introspect->good_size(&sanitizer_zone, size);
 171 }
 172
 173 INTERCEPTOR(int, posix_memalign, void **memptr, size_t alignment, size_t size) {
 174   COMMON_MALLOC_ENTER();
 175   CHECK(memptr);
 176   COMMON_MALLOC_POSIX_MEMALIGN(memptr, alignment, size);
 177   return res;
 178 }
 179
 180 namespace {
 181
 182 // TODO(glider): the __sanitizer_mz_* functions should be united with the Linux
 183 // wrappers, as they are basically copied from there.
 184 extern "C"
 185 SANITIZER_INTERFACE_ATTRIBUTE
 186 size_t __sanitizer_mz_size(malloc_zone_t* zone, const void* ptr) {
 187   COMMON_MALLOC_SIZE(ptr);
 188   return size;
 189 }
 190
 191 extern "C"
 192 SANITIZER_INTERFACE_ATTRIBUTE
 193 void *__sanitizer_mz_malloc(malloc_zone_t *zone, uptr size) {
 194   COMMON_MALLOC_ENTER();
 195   COMMON_MALLOC_MALLOC(size);
 196   return p;
 197 }
 198
 199 extern "C"
 200 SANITIZER_INTERFACE_ATTRIBUTE
 201 void *__sanitizer_mz_calloc(malloc_zone_t *zone, size_t nmemb, size_t size) {
 202   if (UNLIKELY(!COMMON_MALLOC_SANITIZER_INITIALIZED)) {
 203     // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
 204     const size_t kCallocPoolSize = 1024;
 205     static uptr calloc_memory_for_dlsym[kCallocPoolSize];
 206     static size_t allocated;
 207     size_t size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize;
 208     void *mem = (void*)&calloc_memory_for_dlsym[allocated];
 209     allocated += size_in_words;
 210     CHECK(allocated < kCallocPoolSize);
 211     return mem;
 212   }
 213   COMMON_MALLOC_CALLOC(nmemb, size);
 214   return p;
 215 }
 216
 217 extern "C"
 218 SANITIZER_INTERFACE_ATTRIBUTE
 219 void *__sanitizer_mz_valloc(malloc_zone_t *zone, size_t size) {
 220   COMMON_MALLOC_ENTER();
 221   COMMON_MALLOC_VALLOC(size);
 222   return p;
 223 }
 224
 225 // TODO(glider): the allocation callbacks need to be refactored.
 226 extern "C"
 227 SANITIZER_INTERFACE_ATTRIBUTE
 228 void __sanitizer_mz_free(malloc_zone_t *zone, void *ptr) {
 229   if (!ptr) return;
 230   COMMON_MALLOC_FREE(ptr);
 231 }
 232
 233 #define GET_ZONE_FOR_PTR(ptr) \
 234   malloc_zone_t *zone_ptr = WRAP(malloc_zone_from_ptr)(ptr); \
 235   const char *zone_name = (zone_ptr == 0) ? 0 : zone_ptr->zone_name
 236
 237 extern "C"
 238 SANITIZER_INTERFACE_ATTRIBUTE
 239 void *__sanitizer_mz_realloc(malloc_zone_t *zone, void *ptr, size_t new_size) {
 240   if (!ptr) {
 241     COMMON_MALLOC_MALLOC(new_size);
 242     return p;
 243   } else {
 244     COMMON_MALLOC_SIZE(ptr);
 245     if (size) {
 246       COMMON_MALLOC_REALLOC(ptr, new_size);
 247       return p;
 248     } else {
 249       // We can't recover from reallocating an unknown address, because
 250       // this would require reading at most |new_size| bytes from
 251       // potentially unaccessible memory.
 252       GET_ZONE_FOR_PTR(ptr);
 253       COMMON_MALLOC_REPORT_UNKNOWN_REALLOC(ptr, zone_ptr, zone_name);
 254       return nullptr;
 255     }
 256   }
 257 }
 258
 259 extern "C"
 260 SANITIZER_INTERFACE_ATTRIBUTE
 261 void __sanitizer_mz_destroy(malloc_zone_t* zone) {
 262   // A no-op -- we will not be destroyed!
 263   Report("__sanitizer_mz_destroy() called -- ignoring\n");
 264 }
 265
 266 extern "C"
 267 SANITIZER_INTERFACE_ATTRIBUTE
 268 void *__sanitizer_mz_memalign(malloc_zone_t *zone, size_t align, size_t size) {
 269   COMMON_MALLOC_ENTER();
 270   COMMON_MALLOC_MEMALIGN(align, size);
 271   return p;
 272 }
 273
 274 // This public API exists purely for testing purposes.
 275 extern "C"
 276 SANITIZER_INTERFACE_ATTRIBUTE
 277 malloc_zone_t* __sanitizer_mz_default_zone() {
 278   return &sanitizer_zone;
 279 }
 280
 281 // This function is currently unused, and we build with -Werror.
 282 #if 0
 283 void __sanitizer_mz_free_definite_size(
 284     malloc_zone_t* zone, void *ptr, size_t size) {
 285   // TODO(glider): check that |size| is valid.
 286   UNIMPLEMENTED();
 287 }
 288 #endif
 289
 290 #ifndef COMMON_MALLOC_HAS_ZONE_ENUMERATOR
 291 #error "COMMON_MALLOC_HAS_ZONE_ENUMERATOR must be defined"
 292 #endif
 293 static_assert((COMMON_MALLOC_HAS_ZONE_ENUMERATOR) == 0 ||
 294                   (COMMON_MALLOC_HAS_ZONE_ENUMERATOR) == 1,
 295               "COMMON_MALLOC_HAS_ZONE_ENUMERATOR must be 0 or 1");
 296
 297 #if COMMON_MALLOC_HAS_ZONE_ENUMERATOR
 298 // Forward declare and expect the implementation to provided by
 299 // includer.
 300 kern_return_t mi_enumerator(task_t task, void *, unsigned type_mask,
 301                             vm_address_t zone_address, memory_reader_t reader,
 302                             vm_range_recorder_t recorder);
 303 #else
 304 // Provide stub implementation that fails.
 305 kern_return_t mi_enumerator(task_t task, void *, unsigned type_mask,
 306                             vm_address_t zone_address, memory_reader_t reader,
 307                             vm_range_recorder_t recorder) {
 308   // Not supported.
 309   return KERN_FAILURE;
 310 }
 311 #endif
 312
 313 #ifndef COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT
 314 #error "COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT must be defined"
 315 #endif
 316 static_assert((COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT) == 0 ||
 317                   (COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT) == 1,
 318               "COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT must be 0 or 1");
 319 #if COMMON_MALLOC_HAS_EXTRA_INTROSPECTION_INIT
 320 // Forward declare and expect the implementation to provided by
 321 // includer.
 322 void mi_extra_init(
 323     sanitizer_malloc_introspection_t *mi);
 324 #else
 325 void mi_extra_init(
 326     sanitizer_malloc_introspection_t *mi) {
 327   // Just zero initialize the fields.
 328   mi->allocator_ptr = 0;
 329   mi->allocator_size = 0;
 330 }
 331 #endif
 332
 333 size_t mi_good_size(malloc_zone_t *zone, size_t size) {
 334   // I think it's always safe to return size, but we maybe could do better.
 335   return size;
 336 }
 337
 338 boolean_t mi_check(malloc_zone_t *zone) {
 339   UNIMPLEMENTED();
 340 }
 341
 342 void mi_print(malloc_zone_t *zone, boolean_t verbose) {
 343   UNIMPLEMENTED();
 344 }
 345
 346 void mi_log(malloc_zone_t *zone, void *address) {
 347   // I don't think we support anything like this
 348 }
 349
 350 void mi_force_lock(malloc_zone_t *zone) {
 351   COMMON_MALLOC_FORCE_LOCK();
 352 }
 353
 354 void mi_force_unlock(malloc_zone_t *zone) {
 355   COMMON_MALLOC_FORCE_UNLOCK();
 356 }
 357
 358 void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
 359   COMMON_MALLOC_FILL_STATS(zone, stats);
 360 }
 361
 362 boolean_t mi_zone_locked(malloc_zone_t *zone) {
 363   // UNIMPLEMENTED();
 364   return false;
 365 }
 366
 367 }  // unnamed namespace
 368
 369 namespace COMMON_MALLOC_NAMESPACE {
 370
 371 void InitMallocZoneFields() {
 372   static sanitizer_malloc_introspection_t sanitizer_zone_introspection;
 373   // Ok to use internal_memset, these places are not performance-critical.
 374   internal_memset(&sanitizer_zone_introspection, 0,
 375                   sizeof(sanitizer_zone_introspection));
 376
 377   sanitizer_zone_introspection.enumerator = &mi_enumerator;
 378   sanitizer_zone_introspection.good_size = &mi_good_size;
 379   sanitizer_zone_introspection.check = &mi_check;
 380   sanitizer_zone_introspection.print = &mi_print;
 381   sanitizer_zone_introspection.log = &mi_log;
 382   sanitizer_zone_introspection.force_lock = &mi_force_lock;
 383   sanitizer_zone_introspection.force_unlock = &mi_force_unlock;
 384   sanitizer_zone_introspection.statistics = &mi_statistics;
 385   sanitizer_zone_introspection.zone_locked = &mi_zone_locked;
 386
 387   // Set current allocator enumeration version.
 388   sanitizer_zone_introspection.allocator_enumeration_version =
 389       GetMallocZoneAllocatorEnumerationVersion();
 390
 391   // Perform any sanitizer specific initialization.
 392   mi_extra_init(&sanitizer_zone_introspection);
 393
 394   internal_memset(&sanitizer_zone, 0, sizeof(malloc_zone_t));
 395
 396   // Use version 6 for OSX >= 10.6.
 397   sanitizer_zone.version = 6;
 398   sanitizer_zone.zone_name = COMMON_MALLOC_ZONE_NAME;
 399   sanitizer_zone.size = &__sanitizer_mz_size;
 400   sanitizer_zone.malloc = &__sanitizer_mz_malloc;
 401   sanitizer_zone.calloc = &__sanitizer_mz_calloc;
 402   sanitizer_zone.valloc = &__sanitizer_mz_valloc;
 403   sanitizer_zone.free = &__sanitizer_mz_free;
 404   sanitizer_zone.realloc = &__sanitizer_mz_realloc;
 405   sanitizer_zone.destroy = &__sanitizer_mz_destroy;
 406   sanitizer_zone.batch_malloc = 0;
 407   sanitizer_zone.batch_free = 0;
 408   sanitizer_zone.free_definite_size = 0;
 409   sanitizer_zone.memalign = &__sanitizer_mz_memalign;
 410   sanitizer_zone.introspect = &sanitizer_zone_introspection;
 411 }
 412
 413 void ReplaceSystemMalloc() {
 414   InitMallocZoneFields();
 415
 416   // Register the zone.
 417   malloc_zone_register(&sanitizer_zone);
 418 }
 419
 420 }  // namespace COMMON_MALLOC_NAMESPACE