Bug 202265 – Webthread crash in iOS

• Component: WebCore JavaScript
• Status: RESOLVED INVALID

[Raghav]

Found a Webthread crash in iOS application for WKWebview, Below is the stack trace for the crash:

    #2. Crashed: WebThread
    0  WebCore                        0x1bc7e83c4 WebCore::CrossOriginPreflightChecker::validatePreflightResponse(WebCore::DocumentThreadableLoader&, WebCore::ResourceRequest&&, unsigned long, WebCore::ResourceResponse const&) + 460
    1  WebCore                        0x1bc7e83c4 WebCore::CrossOriginPreflightChecker::validatePreflightResponse(WebCore::DocumentThreadableLoader&, WebCore::ResourceRequest&&, unsigned long, WebCore::ResourceResponse const&) + 460
    2  WebCore                        0x1bc7e8f88 WebCore::CrossOriginPreflightChecker::doPreflight(WebCore::DocumentThreadableLoader&, WebCore::ResourceRequest&&) + 1032
    3  WebCore                        0x1bc7fc240 WebCore::DocumentThreadableLoader::makeCrossOriginAccessRequest(WebCore::ResourceRequest&&) + 672
    4  WebCore                        0x1bc7fb024 WebCore::DocumentThreadableLoader::DocumentThreadableLoader(WebCore::Document&, WebCore::ThreadableLoaderClient&, WebCore::DocumentThreadableLoader::BlockingBehavior, WebCore::ResourceRequest&&, WebCore::ThreadableLoaderOptions const&, WTF::RefPtr<WebCore::SecurityOrigin, WTF::DumbPtrTraits<WebCore::SecurityOrigin> >&&, std::__1::unique_ptr<WebCore::ContentSecurityPolicy, std::__1::default_delete<WebCore::ContentSecurityPolicy> >&&, WTF::String&&, WebCore::DocumentThreadableLoader::ShouldLogError) + 1108
    5  WebCore                        0x1bc7fa7c4 WebCore::DocumentThreadableLoader::loadResourceSynchronously(WebCore::Document&, WebCore::ResourceRequest&&, WebCore::ThreadableLoaderClient&, WebCore::ThreadableLoaderOptions const&) + 108
    6  WebCore                        0x1bc8494f8 WebCore::ThreadableLoader::loadResourceSynchronously(WebCore::ScriptExecutionContext&, WebCore::ResourceRequest&&, WebCore::ThreadableLoaderClient&, WebCore::ThreadableLoaderOptions const&) + 92
    7  WebCore                        0x1bced5374 WebCore::XMLHttpRequest::createRequest() + 1180
    8  WebCore                        0x1bced4ad8 WebCore::XMLHttpRequest::send(WTF::String const&) + 804
    9  WebCore                        0x1bced4614 WebCore::XMLHttpRequest::send(WTF::Optional<WTF::Variant<WTF::RefPtr<WebCore::Document, WTF::DumbPtrTraits<WebCore::Document> >, WTF::RefPtr<WebCore::Blob, WTF::DumbPtrTraits<WebCore::Blob> >, WTF::RefPtr<JSC::ArrayBufferView, WTF::DumbPtrTraits<JSC::ArrayBufferView> >, WTF::RefPtr<JSC::ArrayBuffer, WTF::DumbPtrTraits<JSC::ArrayBuffer> >, WTF::RefPtr<WebCore::DOMFormData, WTF::DumbPtrTraits<WebCore::DOMFormData> >, WTF::String> >&&) + 132
    10 WebCore                        0x1bbfb7e88 WebCore::jsXMLHttpRequestPrototypeFunctionSend(JSC::ExecState*) + 292
    11 JavaScriptCore                 0x1ba2d3d8c llint_entry + 89612
    12 JavaScriptCore                 0x1ba2d23a4 llint_entry + 82980
    13 JavaScriptCore                 0x1ba2d23a4 llint_entry + 82980
    14 JavaScriptCore                 0x1ba2bdcec vmEntryToJavaScript + 268
    15 JavaScriptCore                 0x1ba7ef4d0 JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 424
    16 JavaScriptCore                 0x1ba9d168c JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) + 200
    17 WebCore                        0x1bc20facc WebCore::JSExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) + 140
    18 WebCore                        0x1bc22724c WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) + 1092
    19 WebCore                        0x1bc4a2370 WebCore::EventTarget::innerInvokeEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener, WTF::DumbPtrTraits<WebCore::RegisteredEventListener> >, 1ul, WTF::CrashOnOverflow, 16ul>, WebCore::EventTarget::EventInvokePhase) + 740
    20 WebCore                        0x1bc49fbcc WebCore::EventTarget::fireEventListeners(WebCore::Event&, WebCore::EventTarget::EventInvokePhase) + 268
    21 WebCore                        0x1bc49faac WebCore::WindowEventContext::handleLocalEvents(WebCore::Event&, WebCore::EventTarget::EventInvokePhase) const + 120
    22 WebCore                        0x1bc49c518 WebCore::EventDispatcher::dispatchEvent(WebCore::Node&, WebCore::Event&) + 868
    23 WebCore                        0x1bc46e290 WebCore::DocumentEventQueue::pendingEventTimerFired() + 276
    24 WebCore                        0x1bc98e5bc WebCore::ThreadTimers::sharedTimerFiredInternal() + 216
    25 WebCore                        0x1bc9ae608 WebCore::timerFired(__CFRunLoopTimer*, void*) + 28
    26 CoreFoundation                 0x1b2eacd60 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 28
    27 CoreFoundation                 0x1b2eaca90 __CFRunLoopDoTimer + 864
    28 CoreFoundation                 0x1b2eac2c4 __CFRunLoopDoTimers + 248
    29 CoreFoundation                 0x1b2ea7214 __CFRunLoopRun + 1844
    30 CoreFoundation                 0x1b2ea67c0 CFRunLoopRunSpecific + 436
    31 WebCore                        0x1bbb99fc4 RunWebThread(void*) + 600
    32 libsystem_pthread.dylib        0x1b2b392c0 _pthread_body + 128
    33 libsystem_pthread.dylib        0x1b2b39220 _pthread_start + 44
    34 libsystem_pthread.dylib        0x1b2b3ccdc thread_start + 4

[Raghav]

Any idea why this crash is happening?

[Alexey Proskuryakov]

Please e-mail webkit-help for questions about using WebKit.

For a bug report, we would need at least a complete stack trace, but even so, these are only actionable in limited cases:

- there are steps to reproduce;

- or at least the crash is known to be very frequent.