MSVC中的Address Sanitizer：为什么启动时报错？

Question

I'm trying a project that uses Qt with MSVC 2019 with Address Sanitizer. I built with Address Sanitizer the project, but didn't rebuild all libs, including Qt.

it crashes inside Qt in resource initialization (with qRegisterResourceData in the call stack).

Is this:

• Misuse of address sanitizer, like, I should rebuild Qt DLLs with it too?
• An issue in Qt I should investigate deeper?
• Known Qt issue?

I've recreated the issue in Widget application created by Wizard by default. The call stack is as follows:

>   KernelBase.dll!RaiseException() Unknown
    QtWidgetsApplication1.exe!__vcasan::OnAsanReport(const char * description, const char * report, bool __throw) Line 602  C++
    QtWidgetsApplication1.exe!__vcasan::ReportCallback(const char * szReport) Line 325  C++
    clang_rt.asan_dbg_dynamic-x86_64.dll!__asan::ScopedInErrorReport::~ScopedInErrorReport(void)    Unknown
    clang_rt.asan_dbg_dynamic-x86_64.dll!__asan::ReportMallocUsableSizeNotOwned(unsigned __int64,struct __sanitizer::BufferedStackTrace *)  Unknown
    clang_rt.asan_dbg_dynamic-x86_64.dll!__asan::asan_malloc_usable_size(void const *,unsigned __int64,unsigned __int64)    Unknown
    clang_rt.asan_dbg_dynamic-x86_64.dll!_recalloc()    Unknown
    ucrtbased.dll!_register_onexit_function::__l2::<lambda>() Line 112  C++
    ucrtbased.dll!__crt_seh_guarded_call<int>::operator()<void <lambda>(void),int <lambda>(void) &,void <lambda>(void)>(__acrt_lock_and_call::__l2::void <lambda>(void) && setup, _register_onexit_function::__l2::int <lambda>(void) & action, __acrt_lock_and_call::__l2::void <lambda>(void) && cleanup) Line 204    C++
    ucrtbased.dll!__acrt_lock_and_call<int <lambda>(void)>(const __acrt_lock_id lock_id, _register_onexit_function::__l2::int <lambda>(void) && action) Line 980    C++
    ucrtbased.dll!_register_onexit_function(_onexit_table_t * table, int(*)() function) Line 149    C++
    Qt5Cored.dll!_onexit(int(*)() function) Line 267    C++
    Qt5Cored.dll!atexit(void(*)() function) Line 275    C++
    Qt5Cored.dll!QPropertyAnimation::updateState(QAbstractAnimation::State newState, QAbstractAnimation::State oldState) Line 268   C++
    Qt5Cored.dll!QAbstractAnimationPrivate::setState(QAbstractAnimation::State newState) Line 991   C++
    Qt5Cored.dll!QAbstractAnimation::start(QAbstractAnimation::DeletionPolicy policy) Line 1362 C++
    Qt5Widgetsd.dll!QWidgetAnimator::animate(QWidget * widget, const QRect & _final_geometry, bool animate) Line 114    C++
    Qt5Widgetsd.dll!QToolBarAreaLayout::apply(bool animate) Line 936    C++
    Qt5Widgetsd.dll!QMainWindowLayoutState::apply(bool animated) Line 687   C++
    Qt5Widgetsd.dll!QMainWindowLayout::applyState(QMainWindowLayoutState & newState, bool animate) Line 2759    C++
    Qt5Widgetsd.dll!QMainWindowLayout::setGeometry(const QRect & _r) Line 1979  C++
    Qt5Widgetsd.dll!QLayoutPrivate::doResize() Line 596 C++
    Qt5Widgetsd.dll!QLayout::activate() Line 1119   C++
    Qt5Widgetsd.dll!QWidgetPrivate::setVisible(bool visible) Line 8083  C++
    Qt5Widgetsd.dll!QWidget::setVisible(bool visible) Line 8044 C++
    Qt5Widgetsd.dll!QWidget::show() Line 7670   C++
    QtWidgetsApplication1.exe!main(int argc, char * * argv) Line 9  C++
    QtWidgetsApplication1.exe!WinMain(HINSTANCE__ * __formal, HINSTANCE__ * __formal, char * __formal, int __formal) Line 97    C++
    QtWidgetsApplication1.exe!invoke_main() Line 107    C++
    QtWidgetsApplication1.exe!__scrt_common_main_seh() Line 288 C++
    QtWidgetsApplication1.exe!__scrt_common_main() Line 331 C++
    QtWidgetsApplication1.exe!WinMainCRTStartup(void * __formal) Line 17    C++
    kernel32.dll!BaseThreadInitThunk()  Unknown
    ntdll.dll!RtlUserThreadStart()  Unknown

The output:

Address 0x01c416f8eda0 is a wild pointer.
SUMMARY: AddressSanitizer: bad-malloc_usable_size (C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\VC\Tools\MSVC\14.29.30133\bin\HostX86\x64\clang_rt.asan_dbg_dynamic-x86_64.dll+0x18004e63a) in _asan_wrap_GlobalSize+0x4b948
Address Sanitizer Error: bad-malloc_usable_size

Answer 1

The issue is load order .

Qt happens to load before ASan and load C/C++ runtime before ASan DLLs loaded. Qt performs some initialization. So the memory is malloc ed without ASan knowledge, and later ASan sees realloc without prior malloc , which it reports.

Building Qt with ASan should resolve the issue, I have not tried that, as I have found a workaround that does not involve Qt rebuild.

The workaround: just make Qt DLLs import ASan DLLs. For me it is via the following commands:

setdll /d:clang_rt.asan_dbg_dynamic-x86_64.dll <path_to_deployed_debug_app>\Qt5Cored.dll <path_to_deployed_debug_app>\Qt5Guid.dll

setdll /d:clang_rt.asan_dynamic-x86_64.dll <path_to_deployed_release_app>\Qt5Core.dll <path_to_deployed_release_app>\Qt5Gui.dll

setdll is a tool from Detours library that may be obtained from https://github.com/microsoft/Detours and then built using nmake .