crash at QThead::wait

thamht4190

I have a crash at QThread::wait. Here is the stack trace:

FAULTING_IP: 
Qt5Cored!isRecursive+22 [c:\users\qt\work\qt\qtbase\src\corelib\thread\qmutex.cpp @ 65]
00007ffa`7e5b4372 0fb600          movzx   eax,byte ptr [rax]

EXCEPTION_RECORD:  (.exr -1)
ExceptionAddress: 00007ffa7e5b4372 (Qt5Cored!isRecursive+0x0000000000000022)
   ExceptionCode: c0000005 (Access violation)
  ExceptionFlags: 00000000
NumberParameters: 2
   Parameter[0]: 0000000000000000
   Parameter[1]: ffffffffffffffff
Attempt to read from address ffffffffffffffff

DEFAULT_BUCKET_ID:  INVALID_POINTER_READ

PROCESS_NAME:  CortexService.exe

FOLLOWUP_IP: 
Qt5Cored!isRecursive+22 [c:\users\qt\work\qt\qtbase\src\corelib\thread\qmutex.cpp @ 65]
00007ffa`7e5b4372 0fb600          movzx   eax,byte ptr [rax]

READ_ADDRESS:  ffffffffffffffff 

ERROR_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%p referenced memory at 0x%p. The memory could not be %s.

EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%p referenced memory at 0x%p. The memory could not be %s.

EXCEPTION_CODE_STR:  c0000005

EXCEPTION_PARAMETER1:  0000000000000000

EXCEPTION_PARAMETER2:  ffffffffffffffff

WATSON_BKT_PROCSTAMP:  5cecc322

WATSON_BKT_MODULE:  Qt5Cored.dll

WATSON_BKT_MODSTAMP:  5c0513ac

WATSON_BKT_MODOFFSET:  f4372

WATSON_BKT_MODVER:  5.12.0.0

MODULE_VER_PRODUCT:  Qt5

BUILD_VERSION_STRING:  17134.1.amd64fre.rs4_release.180410-1804

ANALYSIS_SESSION_HOST:  DESKTOP-ICB5G90

ANALYSIS_SESSION_TIME:  05-29-2019 16:02:39.0827

ANALYSIS_VERSION: 10.0.18869.1002 amd64fre

THREAD_ATTRIBUTES: 
BUGCHECK_STR:  APPLICATION_FAULT_INVALID_POINTER_READ

PRIMARY_PROBLEM_CLASS:  APPLICATION_FAULT

PROBLEM_CLASSES: 

    ID:     [0n313]
    Type:   [@ACCESS_VIOLATION]
    Class:  Addendum
    Scope:  BUCKET_ID
    Name:   Omit
    Data:   Omit
    PID:    [Unspecified]
    TID:    [0x29f8]
    Frame:  [0] : Qt5Cored!isRecursive

    ID:     [0n285]
    Type:   [INVALID_POINTER_READ]
    Class:  Primary
    Scope:  DEFAULT_BUCKET_ID (Failure Bucket ID prefix)
            BUCKET_ID
    Name:   Add
    Data:   Omit
    PID:    [Unspecified]
    TID:    [0x29f8]
    Frame:  [0] : Qt5Cored!isRecursive

LAST_CONTROL_TRANSFER:  from 00007ffa7e5b3e4b to 00007ffa7e5b4372

STACK_TEXT:  
000000ac`53ffb800 00007ffa`7e5b3e4b : dddddddd`dddddddd 000000ac`53ffb840 00000000`00000000 000002a4`cea17080 : Qt5Cored!isRecursive+0x22
000000ac`53ffb820 00007ffa`7e5ab81c : 000002a4`cea1f520 000002a4`cea1f520 000002a4`00000000 00000000`0000041c : Qt5Cored!QMutex::lock+0x2b
000000ac`53ffb860 00007ff7`5cc0231f : 000002a4`cea16f90 00007ff7`ffffffff 00000000`00000003 00000000`00000000 : Qt5Cored!QThread::wait+0x14c
000000ac`53ffb8e0 00007ff7`5ca73e5e : 000000ac`53cff7c8 00007ff7`5d9f5448 000002a4`000000ad 00007ff7`5d9f53b0 : CortexService!Cortex::API::CortexConnectionManager::stop+0x18f
000000ac`53ffb9c0 00007ff7`5ca74a25 : 000000ac`53cff618 00007ff7`00000000 00000104`00000000 00000000`00000000 : CortexService!CortexService::stop+0xce
000000ac`53ffba80 00007ff7`5ca8ecdc : 000000ac`53cff618 00000000`00000000 00000000`00000000 00000000`00000000 : CortexService!CortexService::signalStopService+0x15
000000ac`53ffbab0 00007ff7`5ca8e9a7 : 00007ff7`5ca74a10 000000ac`53cff618 000002a4`cea8dd80 00000000`00000000 : CortexService!QtPrivate::FunctorCall<QtPrivate::IndexesList<>,QtPrivate::List<>,void,void (__cdecl CortexService::*)(void) __ptr64>::call+0x1c
000000ac`53ffbaf0 00007ff7`5ca8ee4e : 00007ff7`5ca74a10 000000ac`53cff618 000002a4`cea8dd80 00000000`00000000 : CortexService!QtPrivate::FunctionPointer<void (__cdecl CortexService::*)(void) __ptr64>::call<QtPrivate::List<>,void>+0x27
000000ac`53ffbb20 00007ffa`7e995ec8 : 00000000`00000001 000002a4`ce424b90 000000ac`53cff618 000002a4`cea8dd80 : CortexService!QtPrivate::QSlotObject<void (__cdecl CortexService::*)(void) __ptr64,QtPrivate::List<>,void>::impl+0x8e
000000ac`53ffbb70 00007ffa`7e9dd2e6 : 000002a4`ce424b90 000000ac`53cff618 000002a4`cea8dd80 000000ac`53cff618 : Qt5Cored!QtPrivate::QSlotObjectBase::call+0x38
000000ac`53ffbbb0 00007ffa`7e9d5c3f : 000002a4`ce47e930 000000ac`53cff618 000000ac`53cff5e8 00007ffa`00000003 : Qt5Cored!QMetaCallEvent::placeMetaCall+0x36
000000ac`53ffbbf0 00007ffa`7e97dc0e : 000000ac`53cff618 000002a4`ce47e930 000000ac`53cff620 000000ac`53ffbec8 : Qt5Cored!QObject::event+0x12f
000000ac`53ffbe60 00007ffa`7e97f478 : 000000ac`53cff618 000002a4`ce47e930 000002a4`00000000 00007ffa`7e57ba74 : Qt5Cored!QCoreApplicationPrivate::notify_helper+0x9e
000000ac`53ffbea0 00007ffa`7e97b1e1 : 000000ac`53cff618 000002a4`ce47e930 ffffffff`fffffffe 000000ac`53ffbf90 : Qt5Cored!doNotify+0x78
000000ac`53ffbf00 00007ffa`7e97cc56 : 000000ac`53cff5e8 000000ac`53cff618 000002a4`ce47e930 00007ffa`7e5aa4d3 : Qt5Cored!QCoreApplication::notify+0x31
000000ac`53ffbf30 00007ffa`7e97a992 : 000000ac`53cff618 000002a4`ce47e930 00007ffa`7f1d0c30 00007ffa`00000000 : Qt5Cored!QCoreApplication::notifyInternal2+0x116
000000ac`53ffbfb0 00007ffa`7e97e60d : 000000ac`53cff618 000002a4`ce47e930 00007ffa`00000000 000002a4`ce2b25b0 : Qt5Cored!QCoreApplication::sendEvent+0x42
000000ac`53ffbfe0 00007ffa`7ea3fa8a : 00000000`00000000 00007ffa`00000000 000002a4`ce2b25b0 00007ffa`7e989312 : Qt5Cored!QCoreApplicationPrivate::sendPostedEvents+0x47d
000000ac`53ffc0f0 00007ffa`7ea3d878 : 000002a4`ce4e0ee0 00000000`00000000 000000ac`53ffc169 000000ac`53ffc1b0 : Qt5Cored!QEventDispatcherWin32::sendPostedEvents+0x2a
000000ac`53ffc130 00007ffa`d1396d41 : 00000000`0017002e 00000000`00000401 00000000`00000000 00000000`00000000 : Qt5Cored!qt_internal_proc+0x668
000000ac`53ffc2b0 00007ffa`d1396713 : 000002a4`ce4829a0 00007ffa`7e4d622a 00000000`0017002e 00007ffa`00000401 : user32!UserCallWinProcCheckWow+0x2c1
000000ac`53ffc440 00007ffa`7ea3e168 : 000000ac`53ffc538 000000ac`00000000 000000ac`53ffc538 00000000`00000000 : user32!DispatchMessageWorker+0x1c3
000000ac`53ffc4d0 00007ffa`7e976e83 : 000002a4`ce4e0ee0 00007ffa`00000024 000002a4`ce497a84 000002a4`ce497a10 : Qt5Cored!QEventDispatcherWin32::processEvents+0x558
000000ac`53fff660 00007ffa`7e9770be : 000000ac`53fff798 000000ac`00000024 000000ac`00000020 000000ac`53fff700 : Qt5Cored!QEventLoop::processEvents+0x63
000000ac`53fff6a0 00007ffa`7e5a741f : 000000ac`53fff798 00000000`00000000 000002a4`ce2b25e8 00007ffa`7e572673 : Qt5Cored!QEventLoop::exec+0x18e
000000ac`53fff750 00007ffa`7e5a7353 : 000000ac`53cffac8 000000ac`53cffac8 000002a4`ce445800 000000ac`53fff7f8 : Qt5Cored!QThread::exec+0xbf
000000ac`53fff7c0 00007ffa`7e5abc6b : 000000ac`53cffac8 000002a4`ce48e500 00000000`00000000 00000000`00000000 : Qt5Cored!QThread::run+0x13
000000ac`53fff7f0 00007ffa`cf844034 : 000000ac`53cffac8 00000000`00000000 00000000`00000000 00000000`00000000 : Qt5Cored!QThreadPrivate::start+0x15b
000000ac`53fff870 00007ffa`d1c13691 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : kernel32!BaseThreadInitThunk+0x14
000000ac`53fff8a0 00000000`00000000 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : ntdll!RtlUserThreadStart+0x21


THREAD_SHA1_HASH_MOD_FUNC:  5699dc89771ce62f48e0bcfbe264dc112cabad54

THREAD_SHA1_HASH_MOD_FUNC_OFFSET:  1838f892077d904247f98c259bb8f09a59fe89b3

THREAD_SHA1_HASH_MOD:  200f99b5f5d9d4abf8a087e3194d96dace7c8b2c

FAULT_INSTR_CODE:  4800b60f

FAULTING_SOURCE_LINE:  c:\users\qt\work\qt\qtbase\src\corelib\thread\qmutex.cpp

FAULTING_SOURCE_FILE:  c:\users\qt\work\qt\qtbase\src\corelib\thread\qmutex.cpp

FAULTING_SOURCE_LINE_NUMBER:  65

FAULTING_SOURCE_CODE:  
    61: #ifdef QT_LINUX_FUTEX
    62:     Q_ASSERT(d->recursive);
    63:     return true;
    64: #else
>   65:     return d->recursive;
    66: #endif
    67: }
    68: 
    69: class QRecursiveMutexPrivate : public QMutexData
    70: {


SYMBOL_STACK_INDEX:  0

SYMBOL_NAME:  Qt5Cored!isRecursive+22

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: Qt5Cored

IMAGE_NAME:  Qt5Cored.dll

DEBUG_FLR_IMAGE_TIMESTAMP:  5c0513ac

STACK_COMMAND:  ~9s ; .ecxr ; kb

FAILURE_BUCKET_ID:  INVALID_POINTER_READ_c0000005_Qt5Cored.dll!isRecursive

BUCKET_ID:  APPLICATION_FAULT_INVALID_POINTER_READ_Qt5Cored!isRecursive+22

FAILURE_EXCEPTION_CODE:  c0000005

FAILURE_IMAGE_NAME:  Qt5Cored.dll

BUCKET_ID_IMAGE_STR:  Qt5Cored.dll

FAILURE_MODULE_NAME:  Qt5Cored

BUCKET_ID_MODULE_STR:  Qt5Cored

FAILURE_FUNCTION_NAME:  isRecursive

BUCKET_ID_FUNCTION_STR:  isRecursive

BUCKET_ID_OFFSET:  22

BUCKET_ID_MODTIMEDATESTAMP:  5c0513ac

BUCKET_ID_MODCHECKSUM:  0

BUCKET_ID_MODVER_STR:  5.12.0.0

BUCKET_ID_PREFIX_STR:  APPLICATION_FAULT_INVALID_POINTER_READ_

FAILURE_PROBLEM_CLASS:  APPLICATION_FAULT

FAILURE_SYMBOL_NAME:  Qt5Cored.dll!isRecursive

TARGET_TIME:  2019-05-29T02:21:32.000Z

OSBUILD:  17134

OSSERVICEPACK:  753

SERVICEPACK_NUMBER: 0

OS_REVISION: 0

SUITE_MASK:  256

PRODUCT_TYPE:  1

OSPLATFORM_TYPE:  x64

OSNAME:  Windows 10

OSEDITION:  Windows 10 WinNt SingleUserTS

OS_LOCALE:  

USER_LCID:  0

OSBUILD_TIMESTAMP:  unknown_date

BUILDDATESTAMP_STR:  180410-1804

BUILDLAB_STR:  rs4_release

BUILDOSVER_STR:  10.0.17134.1.amd64fre.rs4_release.180410-1804

ANALYSIS_SESSION_ELAPSED_TIME:  ef6

ANALYSIS_SOURCE:  UM

FAILURE_ID_HASH_STRING:  um:invalid_pointer_read_c0000005_qt5cored.dll!isrecursive

FAILURE_ID_HASH:  {f1f28c3e-fce7-9e49-1a65-1afc1afc6bbb}

Followup:     MachineOwner
---------

Can anyone have any idea why it can crash on QThead::wait? Is that a Qt issue or my mistake to use QThread?
My application source is quite large and cannot be shared, so please understand that I cannot share source code here.
The crash happens sometimes. Even I cannot reproduce the crash on my machine.

J.Hilk

hi @thamht4190 and welcome

from what I can see,

I would say you try to access your Thread instance, when its already deleted. Since it doesn't happen each time and behaves differently on different PC.

I would say you have a race condition on hand.

thamht4190

Thanks very much. I will continue my investigation on your diagnose.

A.A.SEZEN

ExceptionAddress: 00007ffa7e5b4372 (Qt5Cored!isRecursive+0x0000000000000022)
ExceptionCode: c0000005 (Access violation)
/////
Hi,
Is there access to unauthorized memory in a loop?

thamht4190

@A.A.SEZEN Uhm, I think @J-Hilk is right: sometimes my Thread instance has been destroyed. I have fixed by using checking null before calling it, I don't see the crash anymore.