//===-- asan_rtl.cc -------------------------------------------------------===// // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file is a part of AddressSanitizer, an address sanity checker. // // Main file of the ASan run-time library. //===----------------------------------------------------------------------===// #include "asan_activation.h" #include "asan_allocator.h" #include "asan_interceptors.h" #include "asan_interface_internal.h" #include "asan_internal.h" #include "asan_mapping.h" #include "asan_poisoning.h" #include "asan_report.h" #include "asan_stack.h" #include "asan_stats.h" #include "asan_suppressions.h" #include "asan_thread.h" #include "sanitizer_common/sanitizer_atomic.h" #include "sanitizer_common/sanitizer_flags.h" #include "sanitizer_common/sanitizer_libc.h" #include "sanitizer_common/sanitizer_symbolizer.h" #include "lsan/lsan_common.h" #include "ubsan/ubsan_init.h" #include "ubsan/ubsan_platform.h" int __asan_option_detect_stack_use_after_return; // Global interface symbol. uptr *__asan_test_only_reported_buggy_pointer; // Used only for testing asan. namespace __asan { uptr AsanMappingProfile[kAsanMappingProfileSize]; static void AsanDie() { static atomic_uint32_t num_calls; if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) { // Don't die twice - run a busy loop. while (1) { } } if (flags()->sleep_before_dying) { Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying); SleepForSeconds(flags()->sleep_before_dying); } if (flags()->unmap_shadow_on_exit) { if (kMidMemBeg) { UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg); UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd); } else { UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg); } } } static void AsanCheckFailed(const char *file, int line, const char *cond, u64 v1, u64 v2) { Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file, line, cond, (uptr)v1, (uptr)v2); // FIXME: check for infinite recursion without a thread-local counter here. PRINT_CURRENT_STACK_CHECK(); Die(); } // -------------------------- Globals --------------------- {{{1 int asan_inited; bool asan_init_is_running; #if !ASAN_FIXED_MAPPING uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; #endif // -------------------------- Misc ---------------- {{{1 void ShowStatsAndAbort() { __asan_print_accumulated_stats(); Die(); } // ---------------------- mmap -------------------- {{{1 // Reserve memory range [beg, end]. // We need to use inclusive range because end+1 may not be representable. void ReserveShadowMemoryRange(uptr beg, uptr end, const char *name) { CHECK_EQ((beg % GetPageSizeCached()), 0); CHECK_EQ(((end + 1) % GetPageSizeCached()), 0); uptr size = end - beg + 1; DecreaseTotalMmap(size); // Don't count the shadow against mmap_limit_mb. void *res = MmapFixedNoReserve(beg, size, name); if (res != (void*)beg) { Report("ReserveShadowMemoryRange failed while trying to map 0x%zx bytes. " "Perhaps you're using ulimit -v\n", size); Abort(); } if (common_flags()->no_huge_pages_for_shadow) NoHugePagesInRegion(beg, size); if (common_flags()->use_madv_dontdump) DontDumpShadowMemory(beg, size); } // --------------- LowLevelAllocateCallbac ---------- {{{1 static void OnLowLevelAllocate(uptr ptr, uptr size) { PoisonShadow(ptr, size, kAsanInternalHeapMagic); } // -------------------------- Run-time entry ------------------- {{{1 // exported functions #define ASAN_REPORT_ERROR(type, is_write, size) \ extern "C" NOINLINE INTERFACE_ATTRIBUTE \ void __asan_report_ ## type ## size(uptr addr) { \ GET_CALLER_PC_BP_SP; \ __asan_report_error(pc, bp, sp, addr, is_write, size, 0); \ } \ extern "C" NOINLINE INTERFACE_ATTRIBUTE \ void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) { \ GET_CALLER_PC_BP_SP; \ __asan_report_error(pc, bp, sp, addr, is_write, size, exp); \ } ASAN_REPORT_ERROR(load, false, 1) ASAN_REPORT_ERROR(load, false, 2) ASAN_REPORT_ERROR(load, false, 4) ASAN_REPORT_ERROR(load, false, 8) ASAN_REPORT_ERROR(load, false, 16) ASAN_REPORT_ERROR(store, true, 1) ASAN_REPORT_ERROR(store, true, 2) ASAN_REPORT_ERROR(store, true, 4) ASAN_REPORT_ERROR(store, true, 8) ASAN_REPORT_ERROR(store, true, 16) #define ASAN_REPORT_ERROR_N(type, is_write) \ extern "C" NOINLINE INTERFACE_ATTRIBUTE \ void __asan_report_ ## type ## _n(uptr addr, uptr size) { \ GET_CALLER_PC_BP_SP; \ __asan_report_error(pc, bp, sp, addr, is_write, size, 0); \ } \ extern "C" NOINLINE INTERFACE_ATTRIBUTE \ void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) { \ GET_CALLER_PC_BP_SP; \ __asan_report_error(pc, bp, sp, addr, is_write, size, exp); \ } ASAN_REPORT_ERROR_N(load, false) ASAN_REPORT_ERROR_N(store, true) #define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg) \ uptr sp = MEM_TO_SHADOW(addr); \ uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast(sp) \ : *reinterpret_cast(sp); \ if (UNLIKELY(s)) { \ if (UNLIKELY(size >= SHADOW_GRANULARITY || \ ((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >= \ (s8)s)) { \ if (__asan_test_only_reported_buggy_pointer) { \ *__asan_test_only_reported_buggy_pointer = addr; \ } else { \ GET_CALLER_PC_BP_SP; \ __asan_report_error(pc, bp, sp, addr, is_write, size, exp_arg); \ } \ } \ } #define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size) \ extern "C" NOINLINE INTERFACE_ATTRIBUTE \ void __asan_##type##size(uptr addr) { \ ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0) \ } \ extern "C" NOINLINE INTERFACE_ATTRIBUTE \ void __asan_exp_##type##size(uptr addr, u32 exp) { \ ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp) \ } ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1) ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2) ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4) ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8) ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16) ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1) ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2) ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4) ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8) ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16) extern "C" NOINLINE INTERFACE_ATTRIBUTE void __asan_loadN(uptr addr, uptr size) { if (__asan_region_is_poisoned(addr, size)) { GET_CALLER_PC_BP_SP; __asan_report_error(pc, bp, sp, addr, false, size, 0); } } extern "C" NOINLINE INTERFACE_ATTRIBUTE void __asan_exp_loadN(uptr addr, uptr size, u32 exp) { if (__asan_region_is_poisoned(addr, size)) { GET_CALLER_PC_BP_SP; __asan_report_error(pc, bp, sp, addr, false, size, exp); } } extern "C" NOINLINE INTERFACE_ATTRIBUTE void __asan_storeN(uptr addr, uptr size) { if (__asan_region_is_poisoned(addr, size)) { GET_CALLER_PC_BP_SP; __asan_report_error(pc, bp, sp, addr, true, size, 0); } } extern "C" NOINLINE INTERFACE_ATTRIBUTE void __asan_exp_storeN(uptr addr, uptr size, u32 exp) { if (__asan_region_is_poisoned(addr, size)) { GET_CALLER_PC_BP_SP; __asan_report_error(pc, bp, sp, addr, true, size, exp); } } // Force the linker to keep the symbols for various ASan interface functions. // We want to keep those in the executable in order to let the instrumented // dynamic libraries access the symbol even if it is not used by the executable // itself. This should help if the build system is removing dead code at link // time. static NOINLINE void force_interface_symbols() { volatile int fake_condition = 0; // prevent dead condition elimination. // __asan_report_* functions are noreturn, so we need a switch to prevent // the compiler from removing any of them. switch (fake_condition) { case 1: __asan_report_load1(0); break; case 2: __asan_report_load2(0); break; case 3: __asan_report_load4(0); break; case 4: __asan_report_load8(0); break; case 5: __asan_report_load16(0); break; case 6: __asan_report_load_n(0, 0); break; case 7: __asan_report_store1(0); break; case 8: __asan_report_store2(0); break; case 9: __asan_report_store4(0); break; case 10: __asan_report_store8(0); break; case 11: __asan_report_store16(0); break; case 12: __asan_report_store_n(0, 0); break; case 13: __asan_report_exp_load1(0, 0); break; case 14: __asan_report_exp_load2(0, 0); break; case 15: __asan_report_exp_load4(0, 0); break; case 16: __asan_report_exp_load8(0, 0); break; case 17: __asan_report_exp_load16(0, 0); break; case 18: __asan_report_exp_load_n(0, 0, 0); break; case 19: __asan_report_exp_store1(0, 0); break; case 20: __asan_report_exp_store2(0, 0); break; case 21: __asan_report_exp_store4(0, 0); break; case 22: __asan_report_exp_store8(0, 0); break; case 23: __asan_report_exp_store16(0, 0); break; case 24: __asan_report_exp_store_n(0, 0, 0); break; case 25: __asan_register_globals(nullptr, 0); break; case 26: __asan_unregister_globals(nullptr, 0); break; case 27: __asan_set_death_callback(nullptr); break; case 28: __asan_set_error_report_callback(nullptr); break; case 29: __asan_handle_no_return(); break; case 30: __asan_address_is_poisoned(nullptr); break; case 31: __asan_poison_memory_region(nullptr, 0); break; case 32: __asan_unpoison_memory_region(nullptr, 0); break; case 34: __asan_before_dynamic_init(nullptr); break; case 35: __asan_after_dynamic_init(); break; case 36: __asan_poison_stack_memory(0, 0); break; case 37: __asan_unpoison_stack_memory(0, 0); break; case 38: __asan_region_is_poisoned(0, 0); break; case 39: __asan_describe_address(0); break; } } static void asan_atexit() { Printf("AddressSanitizer exit stats:\n"); __asan_print_accumulated_stats(); // Print AsanMappingProfile. for (uptr i = 0; i < kAsanMappingProfileSize; i++) { if (AsanMappingProfile[i] == 0) continue; Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]); } } static void InitializeHighMemEnd() { #if !ASAN_FIXED_MAPPING kHighMemEnd = GetMaxVirtualAddress(); // Increase kHighMemEnd to make sure it's properly // aligned together with kHighMemBeg: kHighMemEnd |= SHADOW_GRANULARITY * GetPageSizeCached() - 1; #endif // !ASAN_FIXED_MAPPING CHECK_EQ((kHighMemBeg % GetPageSizeCached()), 0); } static void ProtectGap(uptr addr, uptr size) { void *res = MmapNoAccess(addr, size, "shadow gap"); if (addr == (uptr)res) return; // A few pages at the start of the address space can not be protected. // But we really want to protect as much as possible, to prevent this memory // being returned as a result of a non-FIXED mmap(). if (addr == kZeroBaseShadowStart) { uptr step = GetPageSizeCached(); while (size > step && addr < kZeroBaseMaxShadowStart) { addr += step; size -= step; void *res = MmapNoAccess(addr, size, "shadow gap"); if (addr == (uptr)res) return; } } Report("ERROR: Failed to protect the shadow gap. " "ASan cannot proceed correctly. ABORTING.\n"); DumpProcessMap(); Die(); } static void PrintAddressSpaceLayout() { Printf("|| `[%p, %p]` || HighMem ||\n", (void*)kHighMemBeg, (void*)kHighMemEnd); Printf("|| `[%p, %p]` || HighShadow ||\n", (void*)kHighShadowBeg, (void*)kHighShadowEnd); if (kMidMemBeg) { Printf("|| `[%p, %p]` || ShadowGap3 ||\n", (void*)kShadowGap3Beg, (void*)kShadowGap3End); Printf("|| `[%p, %p]` || MidMem ||\n", (void*)kMidMemBeg, (void*)kMidMemEnd); Printf("|| `[%p, %p]` || ShadowGap2 ||\n", (void*)kShadowGap2Beg, (void*)kShadowGap2End); Printf("|| `[%p, %p]` || MidShadow ||\n", (void*)kMidShadowBeg, (void*)kMidShadowEnd); } Printf("|| `[%p, %p]` || ShadowGap ||\n", (void*)kShadowGapBeg, (void*)kShadowGapEnd); if (kLowShadowBeg) { Printf("|| `[%p, %p]` || LowShadow ||\n", (void*)kLowShadowBeg, (void*)kLowShadowEnd); Printf("|| `[%p, %p]` || LowMem ||\n", (void*)kLowMemBeg, (void*)kLowMemEnd); } Printf("MemToShadow(shadow): %p %p %p %p", (void*)MEM_TO_SHADOW(kLowShadowBeg), (void*)MEM_TO_SHADOW(kLowShadowEnd), (void*)MEM_TO_SHADOW(kHighShadowBeg), (void*)MEM_TO_SHADOW(kHighShadowEnd)); if (kMidMemBeg) { Printf(" %p %p", (void*)MEM_TO_SHADOW(kMidShadowBeg), (void*)MEM_TO_SHADOW(kMidShadowEnd)); } Printf("\n"); Printf("redzone=%zu\n", (uptr)flags()->redzone); Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone); Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb); Printf("malloc_context_size=%zu\n", (uptr)common_flags()->malloc_context_size); Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE); Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY); Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET); CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7); if (kMidMemBeg) CHECK(kMidShadowBeg > kLowShadowEnd && kMidMemBeg > kMidShadowEnd && kHighShadowBeg > kMidMemEnd); } static void AsanInitInternal() { if (LIKELY(asan_inited)) return; SanitizerToolName = "AddressSanitizer"; CHECK(!asan_init_is_running && "ASan init calls itself!"); asan_init_is_running = true; CacheBinaryName(); // Initialize flags. This must be done early, because most of the // initialization steps look at flags(). InitializeFlags(); CheckVMASize(); AsanCheckIncompatibleRT(); AsanCheckDynamicRTPrereqs(); SetCanPoisonMemory(flags()->poison_heap); SetMallocContextSize(common_flags()->malloc_context_size); InitializeHighMemEnd(); // Make sure we are not statically linked. AsanDoesNotSupportStaticLinkage(); // Install tool-specific callbacks in sanitizer_common. AddDieCallback(AsanDie); SetCheckFailedCallback(AsanCheckFailed); SetPrintfAndReportCallback(AppendToErrorMessageBuffer); __sanitizer_set_report_path(common_flags()->log_path); // Enable UAR detection, if required. __asan_option_detect_stack_use_after_return = flags()->detect_stack_use_after_return; // Re-exec ourselves if we need to set additional env or command line args. MaybeReexec(); // Setup internal allocator callback. SetLowLevelAllocateCallback(OnLowLevelAllocate); InitializeAsanInterceptors(); // Enable system log ("adb logcat") on Android. // Doing this before interceptors are initialized crashes in: // AsanInitInternal -> android_log_write -> __interceptor_strcmp AndroidLogInit(); ReplaceSystemMalloc(); uptr shadow_start = kLowShadowBeg; if (kLowShadowBeg) shadow_start -= GetMmapGranularity(); bool full_shadow_is_available = MemoryRangeIsAvailable(shadow_start, kHighShadowEnd); #if SANITIZER_LINUX && defined(__x86_64__) && defined(_LP64) && \ !ASAN_FIXED_MAPPING if (!full_shadow_is_available) { kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0; kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x4fffffffffULL : 0; } #endif if (Verbosity()) PrintAddressSpaceLayout(); DisableCoreDumperIfNecessary(); if (full_shadow_is_available) { // mmap the low shadow plus at least one page at the left. if (kLowShadowBeg) ReserveShadowMemoryRange(shadow_start, kLowShadowEnd, "low shadow"); // mmap the high shadow. ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd, "high shadow"); // protect the gap. ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); CHECK_EQ(kShadowGapEnd, kHighShadowBeg - 1); } else if (kMidMemBeg && MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) && MemoryRangeIsAvailable(kMidMemEnd + 1, kHighShadowEnd)) { CHECK(kLowShadowBeg != kLowShadowEnd); // mmap the low shadow plus at least one page at the left. ReserveShadowMemoryRange(shadow_start, kLowShadowEnd, "low shadow"); // mmap the mid shadow. ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd, "mid shadow"); // mmap the high shadow. ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd, "high shadow"); // protect the gaps. ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1); ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1); } else { Report("Shadow memory range interleaves with an existing memory mapping. " "ASan cannot proceed correctly. ABORTING.\n"); Report("ASan shadow was supposed to be located in the [%p-%p] range.\n", shadow_start, kHighShadowEnd); DumpProcessMap(); Die(); } AsanTSDInit(PlatformTSDDtor); InstallDeadlySignalHandlers(AsanOnDeadlySignal); AllocatorOptions allocator_options; allocator_options.SetFrom(flags(), common_flags()); InitializeAllocator(allocator_options); MaybeStartBackgroudThread(); SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback); // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited // should be set to 1 prior to initializing the threads. asan_inited = 1; asan_init_is_running = false; if (flags()->atexit) Atexit(asan_atexit); InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir); // Now that ASan runtime is (mostly) initialized, deactivate it if // necessary, so that it can be re-activated when requested. if (flags()->start_deactivated) AsanDeactivate(); // interceptors InitTlsSize(); // Create main thread. AsanThread *main_thread = AsanThread::Create( /* start_routine */ nullptr, /* arg */ nullptr, /* parent_tid */ 0, /* stack */ nullptr, /* detached */ true); CHECK_EQ(0, main_thread->tid()); SetCurrentThread(main_thread); main_thread->ThreadStart(internal_getpid(), /* signal_thread_is_registered */ nullptr); force_interface_symbols(); // no-op. SanitizerInitializeUnwinder(); #if CAN_SANITIZE_LEAKS __lsan::InitCommonLsan(); if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) { Atexit(__lsan::DoLeakCheck); } #endif // CAN_SANITIZE_LEAKS #if CAN_SANITIZE_UB __ubsan::InitAsPlugin(); #endif InitializeSuppressions(); VReport(1, "AddressSanitizer Init done\n"); } // Initialize as requested from some part of ASan runtime library (interceptors, // allocator, etc). void AsanInitFromRtl() { AsanInitInternal(); } #if ASAN_DYNAMIC // Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable // (and thus normal initializers from .preinit_array or modules haven't run). class AsanInitializer { public: // NOLINT AsanInitializer() { AsanInitFromRtl(); } }; static AsanInitializer asan_initializer; #endif // ASAN_DYNAMIC } // namespace __asan // ---------------------- Interface ---------------- {{{1 using namespace __asan; // NOLINT void NOINLINE __asan_handle_no_return() { int local_stack; AsanThread *curr_thread = GetCurrentThread(); uptr PageSize = GetPageSizeCached(); uptr top, bottom; if (curr_thread) { top = curr_thread->stack_top(); bottom = ((uptr)&local_stack - PageSize) & ~(PageSize - 1); } else { // If we haven't seen this thread, try asking the OS for stack bounds. uptr tls_addr, tls_size, stack_size; GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr, &tls_size); top = bottom + stack_size; } static const uptr kMaxExpectedCleanupSize = 64 << 20; // 64M if (top - bottom > kMaxExpectedCleanupSize) { static bool reported_warning = false; if (reported_warning) return; reported_warning = true; Report("WARNING: ASan is ignoring requested __asan_handle_no_return: " "stack top: %p; bottom %p; size: %p (%zd)\n" "False positive error reports may follow\n" "For details see " "http://code.google.com/p/address-sanitizer/issues/detail?id=189\n", top, bottom, top - bottom, top - bottom); return; } PoisonShadow(bottom, top - bottom, 0); if (curr_thread && curr_thread->has_fake_stack()) curr_thread->fake_stack()->HandleNoReturn(); } void NOINLINE __asan_set_death_callback(void (*callback)(void)) { SetUserDieCallback(callback); } // Initialize as requested from instrumented application code. // We use this call as a trigger to wake up ASan from deactivated state. void __asan_init() { AsanActivate(); AsanInitInternal(); } void __asan_version_mismatch_check() { // Do nothing. }