asan_malloc_mac.cc revision 280031
1//===-- asan_malloc_mac.cc ------------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file is a part of AddressSanitizer, an address sanity checker. 11// 12// Mac-specific malloc interception. 13//===----------------------------------------------------------------------===// 14 15#include "sanitizer_common/sanitizer_platform.h" 16#if SANITIZER_MAC 17 18#include <AvailabilityMacros.h> 19#include <CoreFoundation/CFBase.h> 20#include <dlfcn.h> 21#include <malloc/malloc.h> 22#include <sys/mman.h> 23 24#include "asan_allocator.h" 25#include "asan_interceptors.h" 26#include "asan_internal.h" 27#include "asan_report.h" 28#include "asan_stack.h" 29#include "asan_stats.h" 30#include "sanitizer_common/sanitizer_mac.h" 31 32// Similar code is used in Google Perftools, 33// http://code.google.com/p/google-perftools. 34 35// ---------------------- Replacement functions ---------------- {{{1 36using namespace __asan; // NOLINT 37 38// TODO(glider): do we need both zones? 39static malloc_zone_t *system_malloc_zone = 0; 40static malloc_zone_t asan_zone; 41 42INTERCEPTOR(malloc_zone_t *, malloc_create_zone, 43 vm_size_t start_size, unsigned zone_flags) { 44 ENSURE_ASAN_INITED(); 45 GET_STACK_TRACE_MALLOC; 46 uptr page_size = GetPageSizeCached(); 47 uptr allocated_size = RoundUpTo(sizeof(asan_zone), page_size); 48 malloc_zone_t *new_zone = 49 (malloc_zone_t*)asan_memalign(page_size, allocated_size, 50 &stack, FROM_MALLOC); 51 internal_memcpy(new_zone, &asan_zone, sizeof(asan_zone)); 52 new_zone->zone_name = NULL; // The name will be changed anyway. 53 if (GetMacosVersion() >= MACOS_VERSION_LION) { 54 // Prevent the client app from overwriting the zone contents. 55 // Library functions that need to modify the zone will set PROT_WRITE on it. 56 // This matches the behavior of malloc_create_zone() on OSX 10.7 and higher. 57 mprotect(new_zone, allocated_size, PROT_READ); 58 } 59 return new_zone; 60} 61 62INTERCEPTOR(malloc_zone_t *, malloc_default_zone, void) { 63 ENSURE_ASAN_INITED(); 64 return &asan_zone; 65} 66 67INTERCEPTOR(malloc_zone_t *, malloc_default_purgeable_zone, void) { 68 // FIXME: ASan should support purgeable allocations. 69 // https://code.google.com/p/address-sanitizer/issues/detail?id=139 70 ENSURE_ASAN_INITED(); 71 return &asan_zone; 72} 73 74INTERCEPTOR(void, malloc_make_purgeable, void *ptr) { 75 // FIXME: ASan should support purgeable allocations. Ignoring them is fine 76 // for now. 77 ENSURE_ASAN_INITED(); 78} 79 80INTERCEPTOR(int, malloc_make_nonpurgeable, void *ptr) { 81 // FIXME: ASan should support purgeable allocations. Ignoring them is fine 82 // for now. 83 ENSURE_ASAN_INITED(); 84 // Must return 0 if the contents were not purged since the last call to 85 // malloc_make_purgeable(). 86 return 0; 87} 88 89INTERCEPTOR(void, malloc_set_zone_name, malloc_zone_t *zone, const char *name) { 90 ENSURE_ASAN_INITED(); 91 // Allocate |strlen("asan-") + 1 + internal_strlen(name)| bytes. 92 size_t buflen = 6 + (name ? internal_strlen(name) : 0); 93 InternalScopedString new_name(buflen); 94 if (name && zone->introspect == asan_zone.introspect) { 95 new_name.append("asan-%s", name); 96 name = new_name.data(); 97 } 98 99 // Call the system malloc's implementation for both external and our zones, 100 // since that appropriately changes VM region protections on the zone. 101 REAL(malloc_set_zone_name)(zone, name); 102} 103 104INTERCEPTOR(void *, malloc, size_t size) { 105 ENSURE_ASAN_INITED(); 106 GET_STACK_TRACE_MALLOC; 107 void *res = asan_malloc(size, &stack); 108 return res; 109} 110 111INTERCEPTOR(void, free, void *ptr) { 112 ENSURE_ASAN_INITED(); 113 if (!ptr) return; 114 GET_STACK_TRACE_FREE; 115 asan_free(ptr, &stack, FROM_MALLOC); 116} 117 118INTERCEPTOR(void *, realloc, void *ptr, size_t size) { 119 ENSURE_ASAN_INITED(); 120 GET_STACK_TRACE_MALLOC; 121 return asan_realloc(ptr, size, &stack); 122} 123 124INTERCEPTOR(void *, calloc, size_t nmemb, size_t size) { 125 ENSURE_ASAN_INITED(); 126 GET_STACK_TRACE_MALLOC; 127 return asan_calloc(nmemb, size, &stack); 128} 129 130INTERCEPTOR(void *, valloc, size_t size) { 131 ENSURE_ASAN_INITED(); 132 GET_STACK_TRACE_MALLOC; 133 return asan_memalign(GetPageSizeCached(), size, &stack, FROM_MALLOC); 134} 135 136INTERCEPTOR(size_t, malloc_good_size, size_t size) { 137 ENSURE_ASAN_INITED(); 138 return asan_zone.introspect->good_size(&asan_zone, size); 139} 140 141INTERCEPTOR(int, posix_memalign, void **memptr, size_t alignment, size_t size) { 142 ENSURE_ASAN_INITED(); 143 CHECK(memptr); 144 GET_STACK_TRACE_MALLOC; 145 void *result = asan_memalign(alignment, size, &stack, FROM_MALLOC); 146 if (result) { 147 *memptr = result; 148 return 0; 149 } 150 return -1; 151} 152 153namespace { 154 155// TODO(glider): the __asan_mz_* functions should be united with the Linux 156// wrappers, as they are basically copied from there. 157extern "C" 158SANITIZER_INTERFACE_ATTRIBUTE 159size_t __asan_mz_size(malloc_zone_t* zone, const void* ptr) { 160 return asan_mz_size(ptr); 161} 162 163extern "C" 164SANITIZER_INTERFACE_ATTRIBUTE 165void *__asan_mz_malloc(malloc_zone_t *zone, uptr size) { 166 if (UNLIKELY(!asan_inited)) { 167 CHECK(system_malloc_zone); 168 return malloc_zone_malloc(system_malloc_zone, size); 169 } 170 GET_STACK_TRACE_MALLOC; 171 return asan_malloc(size, &stack); 172} 173 174extern "C" 175SANITIZER_INTERFACE_ATTRIBUTE 176void *__asan_mz_calloc(malloc_zone_t *zone, size_t nmemb, size_t size) { 177 if (UNLIKELY(!asan_inited)) { 178 // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym. 179 const size_t kCallocPoolSize = 1024; 180 static uptr calloc_memory_for_dlsym[kCallocPoolSize]; 181 static size_t allocated; 182 size_t size_in_words = ((nmemb * size) + kWordSize - 1) / kWordSize; 183 void *mem = (void*)&calloc_memory_for_dlsym[allocated]; 184 allocated += size_in_words; 185 CHECK(allocated < kCallocPoolSize); 186 return mem; 187 } 188 GET_STACK_TRACE_MALLOC; 189 return asan_calloc(nmemb, size, &stack); 190} 191 192extern "C" 193SANITIZER_INTERFACE_ATTRIBUTE 194void *__asan_mz_valloc(malloc_zone_t *zone, size_t size) { 195 if (UNLIKELY(!asan_inited)) { 196 CHECK(system_malloc_zone); 197 return malloc_zone_valloc(system_malloc_zone, size); 198 } 199 GET_STACK_TRACE_MALLOC; 200 return asan_memalign(GetPageSizeCached(), size, &stack, FROM_MALLOC); 201} 202 203#define GET_ZONE_FOR_PTR(ptr) \ 204 malloc_zone_t *zone_ptr = malloc_zone_from_ptr(ptr); \ 205 const char *zone_name = (zone_ptr == 0) ? 0 : zone_ptr->zone_name 206 207void ALWAYS_INLINE free_common(void *context, void *ptr) { 208 if (!ptr) return; 209 GET_STACK_TRACE_FREE; 210 // FIXME: need to retire this flag. 211 if (!flags()->mac_ignore_invalid_free) { 212 asan_free(ptr, &stack, FROM_MALLOC); 213 } else { 214 GET_ZONE_FOR_PTR(ptr); 215 WarnMacFreeUnallocated((uptr)ptr, (uptr)zone_ptr, zone_name, &stack); 216 return; 217 } 218} 219 220// TODO(glider): the allocation callbacks need to be refactored. 221extern "C" 222SANITIZER_INTERFACE_ATTRIBUTE 223void __asan_mz_free(malloc_zone_t *zone, void *ptr) { 224 free_common(zone, ptr); 225} 226 227extern "C" 228SANITIZER_INTERFACE_ATTRIBUTE 229void *__asan_mz_realloc(malloc_zone_t *zone, void *ptr, size_t size) { 230 if (!ptr) { 231 GET_STACK_TRACE_MALLOC; 232 return asan_malloc(size, &stack); 233 } else { 234 if (asan_mz_size(ptr)) { 235 GET_STACK_TRACE_MALLOC; 236 return asan_realloc(ptr, size, &stack); 237 } else { 238 // We can't recover from reallocating an unknown address, because 239 // this would require reading at most |size| bytes from 240 // potentially unaccessible memory. 241 GET_STACK_TRACE_FREE; 242 GET_ZONE_FOR_PTR(ptr); 243 ReportMacMzReallocUnknown((uptr)ptr, (uptr)zone_ptr, zone_name, &stack); 244 } 245 } 246} 247 248extern "C" 249SANITIZER_INTERFACE_ATTRIBUTE 250void __asan_mz_destroy(malloc_zone_t* zone) { 251 // A no-op -- we will not be destroyed! 252 Report("__asan_mz_destroy() called -- ignoring\n"); 253} 254 255extern "C" 256SANITIZER_INTERFACE_ATTRIBUTE 257void *__asan_mz_memalign(malloc_zone_t *zone, size_t align, size_t size) { 258 if (UNLIKELY(!asan_inited)) { 259 CHECK(system_malloc_zone); 260 return malloc_zone_memalign(system_malloc_zone, align, size); 261 } 262 GET_STACK_TRACE_MALLOC; 263 return asan_memalign(align, size, &stack, FROM_MALLOC); 264} 265 266// This function is currently unused, and we build with -Werror. 267#if 0 268void __asan_mz_free_definite_size( 269 malloc_zone_t* zone, void *ptr, size_t size) { 270 // TODO(glider): check that |size| is valid. 271 UNIMPLEMENTED(); 272} 273#endif 274 275kern_return_t mi_enumerator(task_t task, void *, 276 unsigned type_mask, vm_address_t zone_address, 277 memory_reader_t reader, 278 vm_range_recorder_t recorder) { 279 // Should enumerate all the pointers we have. Seems like a lot of work. 280 return KERN_FAILURE; 281} 282 283size_t mi_good_size(malloc_zone_t *zone, size_t size) { 284 // I think it's always safe to return size, but we maybe could do better. 285 return size; 286} 287 288boolean_t mi_check(malloc_zone_t *zone) { 289 UNIMPLEMENTED(); 290} 291 292void mi_print(malloc_zone_t *zone, boolean_t verbose) { 293 UNIMPLEMENTED(); 294} 295 296void mi_log(malloc_zone_t *zone, void *address) { 297 // I don't think we support anything like this 298} 299 300void mi_force_lock(malloc_zone_t *zone) { 301 asan_mz_force_lock(); 302} 303 304void mi_force_unlock(malloc_zone_t *zone) { 305 asan_mz_force_unlock(); 306} 307 308void mi_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) { 309 AsanMallocStats malloc_stats; 310 FillMallocStatistics(&malloc_stats); 311 CHECK(sizeof(malloc_statistics_t) == sizeof(AsanMallocStats)); 312 internal_memcpy(stats, &malloc_stats, sizeof(malloc_statistics_t)); 313} 314 315boolean_t mi_zone_locked(malloc_zone_t *zone) { 316 // UNIMPLEMENTED(); 317 return false; 318} 319 320} // unnamed namespace 321 322namespace __asan { 323 324void ReplaceSystemMalloc() { 325 static malloc_introspection_t asan_introspection; 326 // Ok to use internal_memset, these places are not performance-critical. 327 internal_memset(&asan_introspection, 0, sizeof(asan_introspection)); 328 329 asan_introspection.enumerator = &mi_enumerator; 330 asan_introspection.good_size = &mi_good_size; 331 asan_introspection.check = &mi_check; 332 asan_introspection.print = &mi_print; 333 asan_introspection.log = &mi_log; 334 asan_introspection.force_lock = &mi_force_lock; 335 asan_introspection.force_unlock = &mi_force_unlock; 336 asan_introspection.statistics = &mi_statistics; 337 asan_introspection.zone_locked = &mi_zone_locked; 338 339 internal_memset(&asan_zone, 0, sizeof(malloc_zone_t)); 340 341 // Use version 6 for OSX >= 10.6. 342 asan_zone.version = 6; 343 asan_zone.zone_name = "asan"; 344 asan_zone.size = &__asan_mz_size; 345 asan_zone.malloc = &__asan_mz_malloc; 346 asan_zone.calloc = &__asan_mz_calloc; 347 asan_zone.valloc = &__asan_mz_valloc; 348 asan_zone.free = &__asan_mz_free; 349 asan_zone.realloc = &__asan_mz_realloc; 350 asan_zone.destroy = &__asan_mz_destroy; 351 asan_zone.batch_malloc = 0; 352 asan_zone.batch_free = 0; 353 asan_zone.free_definite_size = 0; 354 asan_zone.memalign = &__asan_mz_memalign; 355 asan_zone.introspect = &asan_introspection; 356 357 // Register the ASan zone. 358 malloc_zone_register(&asan_zone); 359} 360} // namespace __asan 361 362#endif // SANITIZER_MAC 363