1//===-- asan_thread.cc ------------------------------------------*- C++ -*-===// 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// Thread-related code. 13//===----------------------------------------------------------------------===// 14#include "asan_allocator.h" 15#include "asan_interceptors.h" 16#include "asan_procmaps.h" 17#include "asan_stack.h" 18#include "asan_thread.h" 19#include "asan_thread_registry.h" 20#include "asan_mapping.h" 21 22namespace __asan { 23 24AsanThread::AsanThread(LinkerInitialized x) 25 : fake_stack_(x), 26 malloc_storage_(x), 27 stats_(x) { } 28 29AsanThread *AsanThread::Create(int parent_tid, thread_callback_t start_routine, 30 void *arg, AsanStackTrace *stack) { 31 size_t size = RoundUpTo(sizeof(AsanThread), kPageSize); 32 AsanThread *thread = (AsanThread*)AsanMmapSomewhereOrDie(size, __FUNCTION__); 33 thread->start_routine_ = start_routine; 34 thread->arg_ = arg; 35 36 AsanThreadSummary *summary = new AsanThreadSummary(parent_tid, stack); 37 summary->set_thread(thread); 38 thread->set_summary(summary); 39 40 return thread; 41} 42 43void AsanThreadSummary::TSDDtor(void *tsd) { 44 AsanThreadSummary *summary = (AsanThreadSummary*)tsd; 45 if (FLAG_v >= 1) { 46 Report("T%d TSDDtor\n", summary->tid()); 47 } 48 if (summary->thread()) { 49 summary->thread()->Destroy(); 50 } 51} 52 53void AsanThread::Destroy() { 54 if (FLAG_v >= 1) { 55 Report("T%d exited\n", tid()); 56 } 57 58 asanThreadRegistry().UnregisterThread(this); 59 CHECK(summary()->thread() == NULL); 60 // We also clear the shadow on thread destruction because 61 // some code may still be executing in later TSD destructors 62 // and we don't want it to have any poisoned stack. 63 ClearShadowForThreadStack(); 64 fake_stack().Cleanup(); 65 size_t size = RoundUpTo(sizeof(AsanThread), kPageSize); 66 AsanUnmapOrDie(this, size); 67} 68 69void AsanThread::Init() { 70 SetThreadStackTopAndBottom(); 71 CHECK(AddrIsInMem(stack_bottom_)); 72 CHECK(AddrIsInMem(stack_top_)); 73 ClearShadowForThreadStack(); 74 if (FLAG_v >= 1) { 75 int local = 0; 76 Report("T%d: stack [%p,%p) size 0x%zx; local=%p\n", 77 tid(), stack_bottom_, stack_top_, 78 stack_top_ - stack_bottom_, &local); 79 } 80 fake_stack_.Init(stack_size()); 81} 82 83thread_return_t AsanThread::ThreadStart() { 84 Init(); 85 if (FLAG_use_sigaltstack) SetAlternateSignalStack(); 86 87 if (!start_routine_) { 88 // start_routine_ == NULL if we're on the main thread or on one of the 89 // OS X libdispatch worker threads. But nobody is supposed to call 90 // ThreadStart() for the worker threads. 91 CHECK(tid() == 0); 92 return 0; 93 } 94 95 thread_return_t res = start_routine_(arg_); 96 malloc_storage().CommitBack(); 97 if (FLAG_use_sigaltstack) UnsetAlternateSignalStack(); 98 99 this->Destroy(); 100 101 return res; 102} 103 104void AsanThread::ClearShadowForThreadStack() { 105 PoisonShadow(stack_bottom_, stack_top_ - stack_bottom_, 0); 106} 107 108const char *AsanThread::GetFrameNameByAddr(uintptr_t addr, uintptr_t *offset) { 109 uintptr_t bottom = 0; 110 bool is_fake_stack = false; 111 if (AddrIsInStack(addr)) { 112 bottom = stack_bottom(); 113 } else { 114 bottom = fake_stack().AddrIsInFakeStack(addr); 115 CHECK(bottom); 116 is_fake_stack = true; 117 } 118 uintptr_t aligned_addr = addr & ~(__WORDSIZE/8 - 1); // align addr. 119 uintptr_t *ptr = (uintptr_t*)aligned_addr; 120 while (ptr >= (uintptr_t*)bottom) { 121 if (ptr[0] == kCurrentStackFrameMagic || 122 (is_fake_stack && ptr[0] == kRetiredStackFrameMagic)) { 123 *offset = addr - (uintptr_t)ptr; 124 return (const char*)ptr[1]; 125 } 126 ptr--; 127 } 128 *offset = 0; 129 return "UNKNOWN"; 130} 131 132} // namespace __asan 133