diff options
Diffstat (limited to 'contrib/llvm-project/compiler-rt/lib/msan/msan_thread.cpp')
-rw-r--r-- | contrib/llvm-project/compiler-rt/lib/msan/msan_thread.cpp | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/msan/msan_thread.cpp b/contrib/llvm-project/compiler-rt/lib/msan/msan_thread.cpp new file mode 100644 index 000000000000..280a7be2d8f4 --- /dev/null +++ b/contrib/llvm-project/compiler-rt/lib/msan/msan_thread.cpp @@ -0,0 +1,123 @@ + +#include "msan_thread.h" + +#include "msan.h" +#include "msan_interface_internal.h" +#include "sanitizer_common/sanitizer_tls_get_addr.h" + +namespace __msan { + +MsanThread *MsanThread::Create(thread_callback_t start_routine, + void *arg) { + uptr PageSize = GetPageSizeCached(); + uptr size = RoundUpTo(sizeof(MsanThread), PageSize); + MsanThread *thread = (MsanThread*)MmapOrDie(size, __func__); + thread->start_routine_ = start_routine; + thread->arg_ = arg; + thread->destructor_iterations_ = GetPthreadDestructorIterations(); + + return thread; +} + +void MsanThread::SetThreadStackAndTls() { + uptr tls_size = 0; + uptr stack_size = 0; + GetThreadStackAndTls(IsMainThread(), &stack_.bottom, &stack_size, &tls_begin_, + &tls_size); + stack_.top = stack_.bottom + stack_size; + tls_end_ = tls_begin_ + tls_size; + + int local; + CHECK(AddrIsInStack((uptr)&local)); +} + +void MsanThread::ClearShadowForThreadStackAndTLS() { + __msan_unpoison((void *)stack_.bottom, stack_.top - stack_.bottom); + if (tls_begin_ != tls_end_) + __msan_unpoison((void *)tls_begin_, tls_end_ - tls_begin_); + DTLS *dtls = DTLS_Get(); + CHECK_NE(dtls, 0); + ForEachDVT(dtls, [](const DTLS::DTV &dtv, int id) { + __msan_unpoison((void *)(dtv.beg), dtv.size); + }); +} + +void MsanThread::Init() { + SetThreadStackAndTls(); + CHECK(MEM_IS_APP(stack_.bottom)); + CHECK(MEM_IS_APP(stack_.top - 1)); + ClearShadowForThreadStackAndTLS(); + malloc_storage().Init(); +} + +void MsanThread::TSDDtor(void *tsd) { + MsanThread *t = (MsanThread*)tsd; + t->Destroy(); +} + +void MsanThread::Destroy() { + malloc_storage().CommitBack(); + // 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. + ClearShadowForThreadStackAndTLS(); + uptr size = RoundUpTo(sizeof(MsanThread), GetPageSizeCached()); + UnmapOrDie(this, size); + DTLS_Destroy(); +} + +thread_return_t MsanThread::ThreadStart() { + 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. + return 0; + } + + thread_return_t res = start_routine_(arg_); + + return res; +} + +MsanThread::StackBounds MsanThread::GetStackBounds() const { + if (!stack_switching_) + return {stack_.bottom, stack_.top}; + const uptr cur_stack = GET_CURRENT_FRAME(); + // Note: need to check next stack first, because FinishSwitchFiber + // may be in process of overwriting stack_.top/bottom_. But in such case + // we are already on the next stack. + if (cur_stack >= next_stack_.bottom && cur_stack < next_stack_.top) + return {next_stack_.bottom, next_stack_.top}; + return {stack_.bottom, stack_.top}; +} + +uptr MsanThread::stack_top() { return GetStackBounds().top; } + +uptr MsanThread::stack_bottom() { return GetStackBounds().bottom; } + +bool MsanThread::AddrIsInStack(uptr addr) { + const auto bounds = GetStackBounds(); + return addr >= bounds.bottom && addr < bounds.top; +} + +void MsanThread::StartSwitchFiber(uptr bottom, uptr size) { + CHECK(!stack_switching_); + next_stack_.bottom = bottom; + next_stack_.top = bottom + size; + stack_switching_ = true; +} + +void MsanThread::FinishSwitchFiber(uptr *bottom_old, uptr *size_old) { + CHECK(stack_switching_); + if (bottom_old) + *bottom_old = stack_.bottom; + if (size_old) + *size_old = stack_.top - stack_.bottom; + stack_.bottom = next_stack_.bottom; + stack_.top = next_stack_.top; + stack_switching_ = false; + next_stack_.top = 0; + next_stack_.bottom = 0; +} + +} // namespace __msan |