blob: 2f2773212f73aac171f2e73989ed951f2a90814f [file] [log] [blame]
//===-- asan_thread.cc ----------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// 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.
//
// Thread-related code.
//===----------------------------------------------------------------------===//
#include "asan_allocator.h"
#include "asan_interceptors.h"
#include "asan_stack.h"
#include "asan_thread.h"
#include "asan_thread_registry.h"
#include "asan_mapping.h"
#include "sanitizer_common/sanitizer_common.h"
namespace __asan {
AsanThread::AsanThread(LinkerInitialized x)
: fake_stack_(x),
malloc_storage_(x),
stats_(x) { }
AsanThread *AsanThread::Create(u32 parent_tid, thread_callback_t start_routine,
void *arg, AsanStackTrace *stack) {
uptr size = RoundUpTo(sizeof(AsanThread), kPageSize);
AsanThread *thread = (AsanThread*)MmapOrDie(size, __FUNCTION__);
thread->start_routine_ = start_routine;
thread->arg_ = arg;
AsanThreadSummary *summary = new AsanThreadSummary(parent_tid, stack);
summary->set_thread(thread);
thread->set_summary(summary);
return thread;
}
void AsanThreadSummary::TSDDtor(void *tsd) {
AsanThreadSummary *summary = (AsanThreadSummary*)tsd;
if (flags()->verbosity >= 1) {
Report("T%d TSDDtor\n", summary->tid());
}
if (summary->thread()) {
summary->thread()->Destroy();
}
}
void AsanThread::Destroy() {
if (flags()->verbosity >= 1) {
Report("T%d exited\n", tid());
}
asanThreadRegistry().UnregisterThread(this);
CHECK(summary()->thread() == 0);
// We also clear the shadow on thread destruction because
// some code may still be executing in later TSD destructors
// and we don't want it to have any poisoned stack.
ClearShadowForThreadStack();
fake_stack().Cleanup();
uptr size = RoundUpTo(sizeof(AsanThread), kPageSize);
UnmapOrDie(this, size);
}
void AsanThread::Init() {
SetThreadStackTopAndBottom();
CHECK(AddrIsInMem(stack_bottom_));
CHECK(AddrIsInMem(stack_top_));
ClearShadowForThreadStack();
if (flags()->verbosity >= 1) {
int local = 0;
Report("T%d: stack [%p,%p) size 0x%zx; local=%p\n",
tid(), (void*)stack_bottom_, (void*)stack_top_,
stack_top_ - stack_bottom_, &local);
}
fake_stack_.Init(stack_size());
}
thread_return_t AsanThread::ThreadStart() {
Init();
if (flags()->use_sigaltstack) SetAlternateSignalStack();
if (!start_routine_) {
// start_routine_ == 0 if we're on the main thread or on one of the
// OS X libdispatch worker threads. But nobody is supposed to call
// ThreadStart() for the worker threads.
CHECK(tid() == 0);
return 0;
}
thread_return_t res = start_routine_(arg_);
malloc_storage().CommitBack();
if (flags()->use_sigaltstack) UnsetAlternateSignalStack();
this->Destroy();
return res;
}
void AsanThread::SetThreadStackTopAndBottom() {
GetThreadStackTopAndBottom(tid() == 0, &stack_top_, &stack_bottom_);
int local;
CHECK(AddrIsInStack((uptr)&local));
}
void AsanThread::ClearShadowForThreadStack() {
PoisonShadow(stack_bottom_, stack_top_ - stack_bottom_, 0);
}
const char *AsanThread::GetFrameNameByAddr(uptr addr, uptr *offset) {
uptr bottom = 0;
bool is_fake_stack = false;
if (AddrIsInStack(addr)) {
bottom = stack_bottom();
} else {
bottom = fake_stack().AddrIsInFakeStack(addr);
CHECK(bottom);
is_fake_stack = true;
}
uptr aligned_addr = addr & ~(__WORDSIZE/8 - 1); // align addr.
u8 *shadow_ptr = (u8*)MemToShadow(aligned_addr);
u8 *shadow_bottom = (u8*)MemToShadow(bottom);
while (shadow_ptr >= shadow_bottom &&
*shadow_ptr != kAsanStackLeftRedzoneMagic) {
shadow_ptr--;
}
while (shadow_ptr >= shadow_bottom &&
*shadow_ptr == kAsanStackLeftRedzoneMagic) {
shadow_ptr--;
}
if (shadow_ptr < shadow_bottom) {
*offset = 0;
return "UNKNOWN";
}
uptr* ptr = (uptr*)SHADOW_TO_MEM((uptr)(shadow_ptr + 1));
CHECK((ptr[0] == kCurrentStackFrameMagic) ||
(is_fake_stack && ptr[0] == kRetiredStackFrameMagic));
*offset = addr - (uptr)ptr;
return (const char*)ptr[1];
}
} // namespace __asan