WebKit: use-after-free in FormSubmission::create CVE-2017-2460 There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on a nightly version of WebKit. The PoC has also been observed to crash Safari 10.0.2 on Mac. Please note: This bug is subject to a 90 day disclosure deadline. If 90 days elapse without a broadly available patch, then the bug report will automatically become visible to the public. With any fix, please give credit for identifying the vulnerability to Ivan Fratric of Google Project Zero. PoC: =================================================================
a ================================================================= Preliminary analysis: The bug is in FormSubmission::create(). This function traverses the vector of form.associatedElements(), however it is possible for JavaScript event handlers to trigger while the vector is being traversed and to resize (reallocate) the vector's buffer. ASan log: ================================================================= ==1013==ERROR: AddressSanitizer: heap-use-after-free on address 0x60c0000a3b48 at pc 0x0001126c7be0 bp 0x7fff55811d50 sp 0x7fff55811d48 READ of size 8 at 0x60c0000a3b48 thread T0 #0 0x1126c7bdf in WebCore::FormSubmission::create(WebCore::HTMLFormElement*, WebCore::FormSubmission::Attributes const&, WTF::PassRefPtr, WebCore::LockHistory, WebCore::FormSubmissionTrigger) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa55bdf) #1 0x1128c2df1 in WebCore::HTMLFormElement::submit(WebCore::Event*, bool, bool, WebCore::FormSubmissionTrigger) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc50df1) #2 0x11312acf0 in WebCore::jsHTMLFormElementPrototypeFunctionSubmitCaller(JSC::ExecState*, WebCore::JSHTMLFormElement*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x14b8cf0) #3 0x1131273cd in long long WebCore::BindingCaller::callOperation<&(WebCore::jsHTMLFormElementPrototypeFunctionSubmitCaller(JSC::ExecState*, WebCore::JSHTMLFormElement*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState*, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x14b53cd) #4 0x3212cc401027 () #5 0x10f3aa26c in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x12c526c) #6 0x10f3aa26c in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x12c526c) #7 0x10f3a383a in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x12be83a) #8 0x10f06247d in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0xf7d47d) #9 0x10efecaa3 in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0xf07aa3) #10 0x10e6de991 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x5f9991) #11 0x10e6deabb in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x5f9abb) #12 0x10e6dee06 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x5f9e06) #13 0x112d24b2e in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x10b2b2e) #14 0x11300a786 in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext*, WebCore::Event*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x1398786) #15 0x112565a05 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x8f3a05) #16 0x11256552f in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x8f352f) #17 0x112454431 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x7e2431) #18 0x112463c2f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x7f1c2f) #19 0x112372aef in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x700aef) #20 0x11236d88e in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x6fb88e) #21 0x1126d93a1 in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa673a1) #22 0x111ed86f7 in WebCore::CachedResourceLoader::loadDone(WebCore::CachedResource*, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x2666f7) #23 0x1144728a3 in WebCore::SubresourceLoader::notifyDone() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x28008a3) #24 0x11447081b in WebCore::SubresourceLoader::didFinishLoading(double) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x27fe81b) #25 0x10acdf615 in void IPC::handleMessage(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(double)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit+0x8de615) #26 0x10acdec2a in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit+0x8ddc2a) #27 0x10a68d1f9 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit+0x28c1f9) #28 0x10a4b0448 in IPC::Connection::dispatchMessage(std::__1::unique_ptr >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit+0xaf448) #29 0x10a4b9614 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit+0xb8614) #30 0x10f99bab3 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x18b6ab3) #31 0x10f99df1e in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x18b8f1e) #32 0x7fff9aa2c7e0 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation+0xaa7e0) #33 0x7fff9aa0bf1b in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation+0x89f1b) #34 0x7fff9aa0b43e in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation+0x8943e) #35 0x7fff9aa0ae37 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation+0x88e37) #36 0x7fff8c153934 in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox+0x30934) #37 0x7fff8c15376e in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox+0x3076e) #38 0x7fff8c1535ae in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox+0x305ae) #39 0x7fff882d1df5 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit+0x48df5) #40 0x7fff882d1225 in -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit+0x48225) #41 0x7fff882c5d7f in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit+0x3cd7f) #42 0x7fff8828f367 in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit+0x6367) #43 0x7fff9375e193 in _xpc_objc_main (/usr/lib/system/libxpc.dylib+0x11193) #44 0x7fff9375cbbd in xpc_main (/usr/lib/system/libxpc.dylib+0xfbbd) #45 0x10a3ebb73 in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development+0x100001b73) #46 0x7fff9765e5ac in start (/usr/lib/system/libdyld.dylib+0x35ac) 0x60c0000a3b48 is located 8 bytes inside of 128-byte region [0x60c0000a3b40,0x60c0000a3bc0) freed by thread T0 here: #0 0x10c9b9cf4 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.0.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib+0x4bcf4) #1 0x10f9e636f in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x190136f) #2 0x1128c8383 in WTF::Vector::expandCapacity(unsigned long, WebCore::FormAssociatedElement**) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc56383) #3 0x1128c48f0 in void WTF::Vector::insert(unsigned long, WebCore::FormAssociatedElement*&&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc528f0) #4 0x1128c4770 in WebCore::HTMLFormElement::registerFormElement(WebCore::FormAssociatedElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc52770) #5 0x11267b4d8 in WebCore::FormAssociatedElement::setForm(WebCore::HTMLFormElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa094d8) #6 0x11267bd4e in WebCore::FormAssociatedElement::resetFormOwner() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa09d4e) #7 0x1128e2fcd in WebCore::HTMLInputElement::finishedInsertingSubtree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc70fcd) #8 0x112008db8 in WebCore::ContainerNode::notifyChildInserted(WebCore::Node&, WebCore::ContainerNode::ChildChangeSource) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x396db8) #9 0x112008a22 in WebCore::ContainerNode::updateTreeAfterInsertion(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x396a22) #10 0x112008518 in WebCore::ContainerNode::appendChildWithoutPreInsertionValidityCheck(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x396518) #11 0x11200ab16 in WebCore::ContainerNode::appendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x398b16) #12 0x113b094eb in WebCore::Node::appendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x1e974eb) #13 0x1133318b7 in WebCore::JSNode::appendChild(JSC::ExecState&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x16bf8b7) #14 0x11332e951 in WebCore::jsNodePrototypeFunctionAppendChildCaller(JSC::ExecState*, WebCore::JSNode*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x16bc951) #15 0x11332aea2 in long long WebCore::BindingCaller::callOperation<&(WebCore::jsNodePrototypeFunctionAppendChildCaller(JSC::ExecState*, WebCore::JSNode*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState*, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x16b8ea2) #16 0x11332ad4e in WebCore::jsNodePrototypeFunctionAppendChild(JSC::ExecState*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x16b8d4e) #17 0x3212cc401027 () #18 0x10f3aa1fa in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x12c51fa) #19 0x10f3aa26c in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x12c526c) #20 0x10f3a383a in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x12be83a) #21 0x10f06247d in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0xf7d47d) #22 0x10efecaa3 in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0xf07aa3) #23 0x10e6de991 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x5f9991) #24 0x10e6deabb in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x5f9abb) #25 0x10e6dee06 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x5f9e06) #26 0x112d24b2e in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x10b2b2e) #27 0x11300a786 in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext*, WebCore::Event*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x1398786) #28 0x112565a05 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x8f3a05) #29 0x11256552f in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x8f352f) previously allocated by thread T0 here: #0 0x10c9b9790 in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.0.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib+0x4b790) #1 0x7fff8ce465a0 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib+0x25a0) #2 0x10f9efdb4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x190adb4) #3 0x10f9e512b in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x190012b) #4 0x10f97c995 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore+0x1897995) #5 0x1128b17c0 in WTF::VectorBufferBase::allocateBuffer(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc3f7c0) #6 0x1128b1ae3 in WTF::Vector::reserveCapacity(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc3fae3) #7 0x1128c8383 in WTF::Vector::expandCapacity(unsigned long, WebCore::FormAssociatedElement**) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc56383) #8 0x1128c48f0 in void WTF::Vector::insert(unsigned long, WebCore::FormAssociatedElement*&&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc528f0) #9 0x1128c4770 in WebCore::HTMLFormElement::registerFormElement(WebCore::FormAssociatedElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc52770) #10 0x11267b4d8 in WebCore::FormAssociatedElement::setForm(WebCore::HTMLFormElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa094d8) #11 0x11267b79c in WebCore::FormAssociatedElement::insertedInto(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa0979c) #12 0x1129386c3 in WebCore::HTMLObjectElement::insertedInto(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xcc66c3) #13 0x112019476 in WebCore::notifyNodeInsertedIntoDocument(WebCore::ContainerNode&, WebCore::Node&, WTF::Vector, 11ul, WTF::CrashOnOverflow, 16ul>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x3a7476) #14 0x112019318 in WebCore::notifyChildNodeInserted(WebCore::ContainerNode&, WebCore::Node&, WTF::Vector, 11ul, WTF::CrashOnOverflow, 16ul>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x3a7318) #15 0x112008c77 in WebCore::ContainerNode::notifyChildInserted(WebCore::Node&, WebCore::ContainerNode::ChildChangeSource) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x396c77) #16 0x11200769a in WebCore::ContainerNode::parserAppendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x39569a) #17 0x11285d09c in WebCore::executeInsertTask(WebCore::HTMLConstructionSiteTask&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xbeb09c) #18 0x112856007 in WebCore::HTMLConstructionSite::executeQueuedTasks() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xbe4007) #19 0x112886d48 in WebCore::HTMLDocumentParser::constructTreeFromHTMLToken(WebCore::HTMLTokenizer::TokenPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc14d48) #20 0x112886902 in WebCore::HTMLDocumentParser::pumpTokenizerLoop(WebCore::HTMLDocumentParser::SynchronousMode, bool, WebCore::PumpSession&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc14902) #21 0x112885b94 in WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc13b94) #22 0x11288758d in WebCore::HTMLDocumentParser::append(WTF::RefPtr&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xc1558d) #23 0x1122f4661 in WebCore::DecodedDataDocumentParser::flush(WebCore::DocumentWriter&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x682661) #24 0x1124201f8 in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x7ae1f8) #25 0x1123e486f in WebCore::DocumentLoader::finishedLoading(double) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x77286f) #26 0x111ec4fb7 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x252fb7) #27 0x111ebfb69 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x24db69) #28 0x1144707e4 in WebCore::SubresourceLoader::didFinishLoading(double) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0x27fe7e4) #29 0x10acdf615 in void IPC::handleMessage(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(double)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit+0x8de615) SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore+0xa55bdf) in WebCore::FormSubmission::create(WebCore::HTMLFormElement*, WebCore::FormSubmission::Attributes const&, WTF::PassRefPtr, WebCore::LockHistory, WebCore::FormSubmissionTrigger) Shadow bytes around the buggy address: 0x1c1800014710: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa 0x1c1800014720: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa 0x1c1800014730: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00 0x1c1800014740: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa 0x1c1800014750: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd =>0x1c1800014760: fa fa fa fa fa fa fa fa fd[fd]fd fd fd fd fd fd 0x1c1800014770: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa 0x1c1800014780: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x1c1800014790: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd 0x1c18000147a0: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa 0x1c18000147b0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==1013==ABORTING This bug is subject to a 90 day disclosure deadline. If 90 days elapse without a broadly available patch, then the bug report will automatically become visible to the public. Found by: ifratric