libsanitizer/asan/asan_malloc_mac.cc

   1 //===-- asan_malloc_mac.cc ------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of AddressSanitizer, an address sanity checker.
   9 //
  10 // Mac-specific malloc interception.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_common/sanitizer_platform.h"
  14 #if SANITIZER_MAC
  15
  16 #include <AvailabilityMacros.h>
  17 #include <CoreFoundation/CFBase.h>
  18 #include <dlfcn.h>
  19 #include <malloc/malloc.h>
  20 #include <sys/mman.h>
  21
  22 #include "asan_allocator.h"
  23 #include "asan_interceptors.h"
  24 #include "asan_internal.h"
  25 #include "asan_report.h"
  26 #include "asan_stack.h"
  27 #include "asan_stats.h"
  28 #include "sanitizer_common/sanitizer_mac.h"
  29
  30 // Similar code is used in Google Perftools,
  31 // http://code.google.com/p/google-perftools.
  32
  33 // ---------------------- Replacement functions ---------------- {{{1
  34 using namespace __asan;  // NOLINT
  35
  36 // TODO(glider): do we need both zones?
  37 static malloc_zone_t *system_malloc_zone = 0;
  38 static malloc_zone_t asan_zone;
  39
  40 INTERCEPTOR(malloc_zone_t *, malloc_create_zone,
  41                              vm_size_t start_size, unsigned zone_flags) {
  42   ENSURE_ASAN_INITED();
  43   GET_STACK_TRACE_MALLOC;
  44   uptr page_size = GetPageSizeCached();
  45   uptr allocated_size = RoundUpTo(sizeof(asan_zone), page_size);
  46   malloc_zone_t *new_zone =
  47       (malloc_zone_t*)asan_memalign(page_size, allocated_size,
  48                                     &stack, FROM_MALLOC);
  49   internal_memcpy(new_zone, &asan_zone, sizeof(asan_zone));
  50   new_zone->zone_name = NULL;  // The name will be changed anyway.
  51   if (GetMacosVersion() >= MACOS_VERSION_LION) {
  52     // Prevent the client app from overwriting the zone contents.
  53     // Library functions that need to modify the zone will set PROT_WRITE on it.
  54     // This matches the behavior of malloc_create_zone() on OSX 10.7 and higher.
  55     mprotect(new_zone, allocated_size, PROT_READ);
  56   }
  57   return new_zone;
  58 }
  59
  60 INTERCEPTOR(malloc_zone_t *, malloc_default_zone, void) {
  61   ENSURE_ASAN_INITED();
  62   return &asan_zone;
  63 }
  64
  65 INTERCEPTOR(malloc_zone_t *, malloc_default_purgeable_zone, void) {
  66   // FIXME: ASan should support purgeable allocations.
  67   // https://code.google.com/p/address-sanitizer/issues/detail?id=139
  68   ENSURE_ASAN_INITED();
  69   return &asan_zone;
  70 }
  71
  72 INTERCEPTOR(void, malloc_make_purgeable, void *ptr) {
  73   // FIXME: ASan should support purgeable allocations. Ignoring them is fine
  74   // for now.
  75   ENSURE_ASAN_INITED();
  76 }
  77
  78 INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) {
  79   // FIXME: ASan should support purgeable allocations. Ignoring them is fine
  80   // for now.
  81   ENSURE_ASAN_INITED();
  82   // Must return 0 if the contents were not purged since the last call to
  83   // malloc_make_purgeable().
  84   return 0;
  85 }
  86
  87 INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) {
  88   ENSURE_ASAN_INITED();
  89   // Allocate |strlen("asan-") + 1 + internal_strlen(name)| bytes.
  90   size_t buflen = 6 + (name ? internal_strlen(name) : 0);
  91   InternalScopedString new_name(buflen);
  92   if (name && zone->introspect == asan_zone.introspect) {
  93     new_name.append("asan-%s", name);
  94     name = new_name.data();
  95   }
  96
  97   // Call the system malloc's implementation for both external and our zones,
  98   // since that appropriately changes VM region protections on the zone.
  99   REAL(malloc_set_zone_name)(zone, name);
 100 }
 101
 102 INTERCEPTOR(void *, malloc, size_t size) {
 103   ENSURE_ASAN_INITED();
 104   GET_STACK_TRACE_MALLOC;
 105   void *res = asan_malloc(size, &stack);
 106   return res;
 107 }
 108
 109 INTERCEPTOR(void, free, void *ptr) {
 110   ENSURE_ASAN_INITED();
 111   if (!ptr) return;
 112   GET_STACK_TRACE_FREE;
 113   asan_free(ptr, &stack, FROM_MALLOC);
 114 }
 115
 116 INTERCEPTOR(void *, realloc, void *ptr, size_t size) {
 117   ENSURE_ASAN_INITED();
 118   GET_STACK_TRACE_MALLOC;
 119   return asan_realloc(ptr, size, &stack);
 120 }
 121
 122 INTERCEPTOR(void *, calloc, size_t nmemb, size_t size) {
 123   ENSURE_ASAN_INITED();
 124   GET_STACK_TRACE_MALLOC;
 125   return asan_calloc(nmemb, size, &stack);
 126 }
 127
 128 INTERCEPTOR(void *, valloc, size_t size) {
 129   ENSURE_ASAN_INITED();
 130   GET_STACK_TRACE_MALLOC;
 131   return asan_memalign(GetPageSizeCached(), size, &stack, FROM_MALLOC);
 132 }
 133
 134 INTERCEPTOR(size_t, malloc_good_size, size_t size) {
 135   ENSURE_ASAN_INITED();
 136   return asan_zone.introspect->good_size(&asan_zone, size);
 137 }
 138
 139 INTERCEPTOR(int, posix_memalign, void **memptr, size_t alignment, size_t size) {
 140   ENSURE_ASAN_INITED();
 141   CHECK(memptr);
 142   GET_STACK_TRACE_MALLOC;
 143   void *result = asan_memalign(alignment, size, &stack, FROM_MALLOC);
 144   if (result) {
 145     *memptr = result;
 146     return 0;
 147   }
 148   return -1;
 149 }
 150
 151 namespace {
 152
 153 // TODO(glider): the __asan_mz_* functions should be united with the Linux
 154 // wrappers, as they are basically copied from there.
 155 extern "C"
 156 SANITIZER_INTERFACE_ATTRIBUTE
 157 size_t __asan_mz_size(malloc_zone_t* zone, const void* ptr) {
 158   return asan_mz_size(ptr);
 159 }
 160
 161 extern "C"
 162 SANITIZER_INTERFACE_ATTRIBUTE
 163 void *__asan_mz_malloc(malloc_zone_t *zone, uptr size) {
 164   if (UNLIKELY(!asan_inited)) {
 165     CHECK(system_malloc_zone);
 166     return malloc_zone_malloc(system_malloc_zone, size);
 167   }
 168   GET_STACK_TRACE_MALLOC;
 169   return asan_malloc(size, &stack);
 170 }
 171
 172 extern "C"
 173 SANITIZER_INTERFACE_ATTRIBUTE
 174 void *__asan_mz_calloc(malloc_zone_t *zone, size_t nmemb, size_t size) {
 175   if (UNLIKELY(!asan_inited)) {
 176     // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
 177     const size_t kCallocPoolSize = 1024;
 178     static uptr calloc_memory_for_dlsym[kCallocPoolSize];
 179     static size_t allocated;
 180     size_t size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize;
 181     void *mem = (void*)&calloc_memory_for_dlsym[allocated];
 182     allocated += size_in_words;
 183     CHECK(allocated < kCallocPoolSize);
 184     return mem;
 185   }
 186   GET_STACK_TRACE_MALLOC;
 187   return asan_calloc(nmemb, size, &stack);
 188 }
 189
 190 extern "C"
 191 SANITIZER_INTERFACE_ATTRIBUTE
 192 void *__asan_mz_valloc(malloc_zone_t *zone, size_t size) {
 193   if (UNLIKELY(!asan_inited)) {
 194     CHECK(system_malloc_zone);
 195     return malloc_zone_valloc(system_malloc_zone, size);
 196   }
 197   GET_STACK_TRACE_MALLOC;
 198   return asan_memalign(GetPageSizeCached(), size, &stack, FROM_MALLOC);
 199 }
 200
 201 #define GET_ZONE_FOR_PTR(ptr) \
 202   malloc_zone_t *zone_ptr = malloc_zone_from_ptr(ptr); \
 203   const char *zone_name = (zone_ptr == 0) ? 0 : zone_ptr->zone_name
 204
 205 void ALWAYS_INLINE free_common(void *context, void *ptr) {
 206   if (!ptr) return;
 207   GET_STACK_TRACE_FREE;
 208   // FIXME: need to retire this flag.
 209   if (!flags()->mac_ignore_invalid_free) {
 210     asan_free(ptr, &stack, FROM_MALLOC);
 211   } else {
 212     GET_ZONE_FOR_PTR(ptr);
 213     WarnMacFreeUnallocated((uptr)ptr, (uptr)zone_ptr, zone_name, &stack);
 214     return;
 215   }
 216 }
 217
 218 // TODO(glider): the allocation callbacks need to be refactored.
 219 extern "C"
 220 SANITIZER_INTERFACE_ATTRIBUTE
 221 void __asan_mz_free(malloc_zone_t *zone, void *ptr) {
 222   free_common(zone, ptr);
 223 }
 224
 225 extern "C"
 226 SANITIZER_INTERFACE_ATTRIBUTE
 227 void *__asan_mz_realloc(malloc_zone_t *zone, void *ptr, size_t size) {
 228   if (!ptr) {
 229     GET_STACK_TRACE_MALLOC;
 230     return asan_malloc(size, &stack);
 231   } else {
 232     if (asan_mz_size(ptr)) {
 233       GET_STACK_TRACE_MALLOC;
 234       return asan_realloc(ptr, size, &stack);
 235     } else {
 236       // We can't recover from reallocating an unknown address, because
 237       // this would require reading at most |size| bytes from
 238       // potentially unaccessible memory.
 239       GET_STACK_TRACE_FREE;
 240       GET_ZONE_FOR_PTR(ptr);
 241       ReportMacMzReallocUnknown((uptr)ptr, (uptr)zone_ptr, zone_name, &stack);
 242     }
 243   }
 244 }
 245
 246 extern "C"
 247 SANITIZER_INTERFACE_ATTRIBUTE
 248 void __asan_mz_destroy(malloc_zone_t* zone) {
 249   // A no-op -- we will not be destroyed!
 250   Report("__asan_mz_destroy() called -- ignoring\n");
 251 }
 252
 253 extern "C"
 254 SANITIZER_INTERFACE_ATTRIBUTE
 255 void *__asan_mz_memalign(malloc_zone_t *zone, size_t align, size_t size) {
 256   if (UNLIKELY(!asan_inited)) {
 257     CHECK(system_malloc_zone);
 258     return malloc_zone_memalign(system_malloc_zone, align, size);
 259   }
 260   GET_STACK_TRACE_MALLOC;
 261   return asan_memalign(align, size, &stack, FROM_MALLOC);
 262 }
 263
 264 // This function is currently unused, and we build with -Werror.
 265 #if 0
 266 void __asan_mz_free_definite_size(
 267     malloc_zone_t* zone, void *ptr, size_t size) {
 268   // TODO(glider): check that |size| is valid.
 269   UNIMPLEMENTED();
 270 }
 271 #endif
 272
 273 kern_return_t mi_enumerator(task_t task, void *,
 274                             unsigned type_mask, vm_address_t zone_address,
 275                             memory_reader_t reader,
 276                             vm_range_recorder_t recorder) {
 277   // Should enumerate all the pointers we have.  Seems like a lot of work.
 278   return KERN_FAILURE;
 279 }
 280
 281 size_t mi_good_size(malloc_zone_t *zone, size_t size) {
 282   // I think it's always safe to return size, but we maybe could do better.
 283   return size;
 284 }
 285
 286 boolean_t mi_check(malloc_zone_t *zone) {
 287   UNIMPLEMENTED();
 288 }
 289
 290 void mi_print(malloc_zone_t *zone, boolean_t verbose) {
 291   UNIMPLEMENTED();
 292 }
 293
 294 void mi_log(malloc_zone_t *zone, void *address) {
 295   // I don't think we support anything like this
 296 }
 297
 298 void mi_force_lock(malloc_zone_t *zone) {
 299   asan_mz_force_lock();
 300 }
 301
 302 void mi_force_unlock(malloc_zone_t *zone) {
 303   asan_mz_force_unlock();
 304 }
 305
 306 void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
 307   AsanMallocStats malloc_stats;
 308   FillMallocStatistics(&malloc_stats);
 309   CHECK(sizeof(malloc_statistics_t) == sizeof(AsanMallocStats));
 310   internal_memcpy(stats, &malloc_stats, sizeof(malloc_statistics_t));
 311 }
 312
 313 boolean_t mi_zone_locked(malloc_zone_t *zone) {
 314   // UNIMPLEMENTED();
 315   return false;
 316 }
 317
 318 }  // unnamed namespace
 319
 320 namespace __asan {
 321
 322 void ReplaceSystemMalloc() {
 323   static malloc_introspection_t asan_introspection;
 324   // Ok to use internal_memset, these places are not performance-critical.
 325   internal_memset(&asan_introspection, 0, sizeof(asan_introspection));
 326
 327   asan_introspection.enumerator = &mi_enumerator;
 328   asan_introspection.good_size = &mi_good_size;
 329   asan_introspection.check = &mi_check;
 330   asan_introspection.print = &mi_print;
 331   asan_introspection.log = &mi_log;
 332   asan_introspection.force_lock = &mi_force_lock;
 333   asan_introspection.force_unlock = &mi_force_unlock;
 334   asan_introspection.statistics = &mi_statistics;
 335   asan_introspection.zone_locked = &mi_zone_locked;
 336
 337   internal_memset(&asan_zone, 0, sizeof(malloc_zone_t));
 338
 339   // Use version 6 for OSX >= 10.6.
 340   asan_zone.version = 6;
 341   asan_zone.zone_name = "asan";
 342   asan_zone.size = &__asan_mz_size;
 343   asan_zone.malloc = &__asan_mz_malloc;
 344   asan_zone.calloc = &__asan_mz_calloc;
 345   asan_zone.valloc = &__asan_mz_valloc;
 346   asan_zone.free = &__asan_mz_free;
 347   asan_zone.realloc = &__asan_mz_realloc;
 348   asan_zone.destroy = &__asan_mz_destroy;
 349   asan_zone.batch_malloc = 0;
 350   asan_zone.batch_free = 0;
 351   asan_zone.free_definite_size = 0;
 352   asan_zone.memalign = &__asan_mz_memalign;
 353   asan_zone.introspect = &asan_introspection;
 354
 355   // Register the ASan zone.
 356   malloc_zone_register(&asan_zone);
 357 }
 358 }  // namespace __asan
 359
 360 #endif  // SANITIZER_MAC