<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<!DOCTYPE bugzilla SYSTEM "https://bugs.webkit.org/page.cgi?id=bugzilla.dtd">

<bugzilla version="5.0.4.1"
          urlbase="https://bugs.webkit.org/"
          
          maintainer="admin@webkit.org"
>

    <bug>
          <bug_id>247652</bug_id>
          
          <creation_ts>2022-11-08 15:23:39 -0800</creation_ts>
          <short_desc>Crash in FormData::flatten</short_desc>
          <delta_ts>2022-11-12 15:11:05 -0800</delta_ts>
          <reporter_accessible>1</reporter_accessible>
          <cclist_accessible>1</cclist_accessible>
          <classification_id>1</classification_id>
          <classification>Unclassified</classification>
          <product>WebKit</product>
          <component>Forms</component>
          <version>WebKit Nightly Build</version>
          <rep_platform>Unspecified</rep_platform>
          <op_sys>Unspecified</op_sys>
          <bug_status>RESOLVED</bug_status>
          <resolution>FIXED</resolution>
          
          
          <bug_file_loc></bug_file_loc>
          <status_whiteboard></status_whiteboard>
          <keywords>InRadar</keywords>
          <priority>P2</priority>
          <bug_severity>Normal</bug_severity>
          <target_milestone>---</target_milestone>
          
          
          <everconfirmed>1</everconfirmed>
          <reporter name="Ali Juma">ajuma</reporter>
          <assigned_to name="Ryosuke Niwa">rniwa</assigned_to>
          <cc>beidson</cc>
    
    <cc>bfulgham</cc>
    
    <cc>cdumez</cc>
    
    <cc>fpizlo</cc>
    
    <cc>msaboff</cc>
    
    <cc>rniwa</cc>
    
    <cc>rohitrao</cc>
    
    <cc>webkit-bug-importer</cc>
    
    <cc>wenson_hsieh</cc>
          

      

      

      

          <comment_sort_order>oldest_to_newest</comment_sort_order>  
          <long_desc isprivate="0" >
    <commentid>1911131</commentid>
    <comment_count>0</comment_count>
      <attachid>463460</attachid>
    <who name="Ali Juma">ajuma</who>
    <bug_when>2022-11-08 15:23:39 -0800</bug_when>
    <thetext>Created attachment 463460
Minimal test case

Filing this as a security bug since it was found using a fuzzer; there&apos;s no disclosure deadline for this bug.

This reproduces in an ASan build of WebKitTestRunner at https://commits.webkit.org/256368@main and also reproduces as a crash in STP 156.

Stack:
=================================================================
==83355==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000008 (pc 0x0001450de6dd bp 0x7ffee7bb3eb0 sp 0x7ffee7bb3eb0 T0)
==83355==The signal is caused by a READ memory access.
==83355==Hint: address points to the zero page.
    #0 0x1450de6dd in WTF::VectorBufferBase&lt;WebCore::FormDataElement, WTF::FastMalloc&gt;::buffer() const+0x1d (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x28366dd)
    #1 0x148122f08 in WTF::Vector&lt;WebCore::FormDataElement, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc&gt;::data() const+0x8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x587af08)
    #2 0x14810f8a8 in WTF::Vector&lt;WebCore::FormDataElement, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc&gt;::begin() const+0x8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x58678a8)
    #3 0x148111a67 in WebCore::FormData::flatten() const+0x27 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x5869a67)
    #4 0x148111cc9 in WebCore::FormData::flattenToString() const+0xb9 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x5869cc9)
    #5 0x147447cc9 in WebCore::FormSubmission::requestURL() const+0x169 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4b9fcc9)
    #6 0x146b999f4 in WebCore::HTMLFormElement::submit(WebCore::Event*, bool, WebCore::FormSubmissionTrigger, WebCore::HTMLFormControlElement*)+0x544 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x42f19f4)
    #7 0x146b99d71 in WebCore::HTMLFormElement::submitFromJavaScript()+0x21 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x42f1d71)
    #8 0x143af7944 in WebCore::jsHTMLFormElementPrototypeFunction_submitBody(JSC::JSGlobalObject*, JSC::CallFrame*, WebCore::JSHTMLFormElement*)::&apos;lambda&apos;()::operator()() const+0x24 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x124f944)
    #9 0x143af7918 in JSC::JSValue WebCore::toJS&lt;WebCore::IDLUndefined, WebCore::jsHTMLFormElementPrototypeFunction_submitBody(JSC::JSGlobalObject*, JSC::CallFrame*, WebCore::JSHTMLFormElement*)::&apos;lambda&apos;()&gt;(JSC::JSGlobalObject&amp;, JSC::ThrowScope&amp;, WebCore::jsHTMLFormElementPrototypeFunction_submitBody(JSC::JSGlobalObject*, JSC::CallFrame*, WebCore::JSHTMLFormElement*)::&apos;lambda&apos;()&amp;&amp;)+0x8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x124f918)
    #10 0x143af7873 in WebCore::jsHTMLFormElementPrototypeFunction_submitBody(JSC::JSGlobalObject*, JSC::CallFrame*, WebCore::JSHTMLFormElement*)+0xe3 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x124f873)
    #11 0x143af770b in long long WebCore::IDLOperation&lt;WebCore::JSHTMLFormElement&gt;::call&lt;&amp;(WebCore::jsHTMLFormElementPrototypeFunction_submitBody(JSC::JSGlobalObject*, JSC::CallFrame*, WebCore::JSHTMLFormElement*)), (WebCore::CastedThisErrorBehavior)0&gt;(JSC::JSGlobalObject&amp;, JSC::CallFrame&amp;, char const*)+0xfb (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x124f70b)
    #12 0x143af75c8 in WebCore::jsHTMLFormElementPrototypeFunction_submit(JSC::JSGlobalObject*, JSC::CallFrame*)+0x8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x124f5c8)
    #13 0x398a4a80c037  (&lt;unknown module&gt;)
    #14 0x164b3a90e in llint_entry+0x1d302 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x103290e)
    #15 0x164b3a90e in llint_entry+0x1d302 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x103290e)
    #16 0x164b1d405 in vmEntryToJavaScript+0xd4 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1015405)
    #17 0x1666ee604 in JSC::Interpreter::executeCall(JSC::JSGlobalObject*, JSC::JSObject*, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;)+0x654 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x2be6604)
    #18 0x16712fd49 in JSC::call(JSC::JSGlobalObject*, JSC::JSValue, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;)+0x49 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x3627d49)
    #19 0x16712fe3f in JSC::call(JSC::JSGlobalObject*, JSC::JSValue, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;, WTF::NakedPtr&lt;JSC::Exception&gt;&amp;)+0xdf (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x3627e3f)
    #20 0x1671301fb in JSC::profiledCall(JSC::JSGlobalObject*, JSC::ProfilingReason, JSC::JSValue, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;, WTF::NakedPtr&lt;JSC::Exception&gt;&amp;)+0x10b (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x36281fb)
    #21 0x145bfe9ff in WebCore::JSExecState::profiledCall(JSC::JSGlobalObject*, JSC::ProfilingReason, JSC::JSValue, JSC::CallData const&amp;, JSC::JSValue, JSC::ArgList const&amp;, WTF::NakedPtr&lt;JSC::Exception&gt;&amp;)+0x10f (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x33569ff)
    #22 0x145c2f735 in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&amp;, WebCore::Event&amp;)+0xb05 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x3387735)
    #23 0x14673af62 in WebCore::EventTarget::innerInvokeEventListeners(WebCore::Event&amp;, WTF::Vector&lt;WTF::RefPtr&lt;WebCore::RegisteredEventListener, WTF::RawPtrTraits&lt;WebCore::RegisteredEventListener&gt;, WTF::DefaultRefDerefTraits&lt;WebCore::RegisteredEventListener&gt; &gt;, 1ul, WTF::CrashOnOverflow, 2ul, WTF::FastMalloc&gt;, WebCore::EventTarget::EventInvokePhase)+0x522 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x3e92f62)
    #24 0x14673a84a in WebCore::EventTarget::fireEventListeners(WebCore::Event&amp;, WebCore::EventTarget::EventInvokePhase)+0x12a (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x3e9284a)
    #25 0x1476456e4 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&amp;, WebCore::EventTarget*)+0x384 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4d9d6e4)
    #26 0x14765b40f in WebCore::DOMWindow::dispatchLoadEvent()+0x26f (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4db340f)
    #27 0x1465f02c5 in WebCore::Document::dispatchWindowLoadEvent()+0x55 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x3d482c5)
    #28 0x1465efc01 in WebCore::Document::implicitClose()+0x361 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x3d47c01)
    #29 0x147453368 in WebCore::FrameLoader::checkCallImplicitClose()+0xd8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4bab368)
    #30 0x1474528e2 in WebCore::FrameLoader::checkCompleted()+0x2b2 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4baa8e2)
    #31 0x14744eea8 in WebCore::FrameLoader::finishedParsing()+0x1b8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4ba6ea8)
    #32 0x14661380e in WebCore::Document::finishedParsing()+0x2fe (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x3d6b80e)
    #33 0x146e9b9c4 in WebCore::HTMLConstructionSite::finishedParsing()+0x24 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x45f39c4)
    #34 0x146f02f3d in WebCore::HTMLTreeBuilder::finished()+0x1d (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x465af3d)
    #35 0x146ea4bd7 in WebCore::HTMLDocumentParser::end()+0x17 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x45fcbd7)
    #36 0x146ea2898 in WebCore::HTMLDocumentParser::attemptToRunDeferredScriptsAndEnd()+0x38 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x45fa898)
    #37 0x146ea27b0 in WebCore::HTMLDocumentParser::prepareToStopParsing()+0x110 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x45fa7b0)
    #38 0x146ea4c1f in WebCore::HTMLDocumentParser::attemptToEnd()+0x3f (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x45fcc1f)
    #39 0x146ea4cb9 in WebCore::HTMLDocumentParser::finish()+0x29 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x45fccb9)
    #40 0x1473e2ac0 in WebCore::DocumentWriter::end()+0x1a0 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4b3aac0)
    #41 0x1473e10e6 in WebCore::DocumentLoader::finishedLoading()+0x306 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4b390e6)
    #42 0x1473e098e in WebCore::DocumentLoader::notifyFinished(WebCore::CachedResource&amp;, WebCore::NetworkLoadMetrics const&amp;)+0x44e (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4b3898e)
    #43 0x1475baa4f in WebCore::CachedResource::checkNotify(WebCore::NetworkLoadMetrics const&amp;)+0x17f (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4d12a4f)
    #44 0x1475b473e in WebCore::CachedResource::finishLoading(WebCore::FragmentedSharedBuffer const*, WebCore::NetworkLoadMetrics const&amp;)+0x4e (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4d0c73e)
    #45 0x1475b4507 in WebCore::CachedRawResource::finishLoading(WebCore::FragmentedSharedBuffer const*, WebCore::NetworkLoadMetrics const&amp;)+0x267 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4d0c507)
    #46 0x14752c96f in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&amp;)+0x5ef (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebCore.framework/Versions/A/WebCore:x86_64+0x4c8496f)
    #47 0x13266361a in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics&amp;&amp;)+0x2ba (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x266361a)
    #48 0x132f4d8e7 in void IPC::callMemberFunctionImpl&lt;WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics&amp;&amp;), std::__1::tuple&lt;WebCore::NetworkLoadMetrics&gt;, 0ul&gt;(WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics&amp;&amp;), std::__1::tuple&lt;WebCore::NetworkLoadMetrics&gt;&amp;&amp;, std::__1::integer_sequence&lt;unsigned long, 0ul&gt;)+0x47 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x2f4d8e7)
    #49 0x132f4d847 in void IPC::callMemberFunction&lt;WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics&amp;&amp;), std::__1::tuple&lt;WebCore::NetworkLoadMetrics&gt;, std::__1::integer_sequence&lt;unsigned long, 0ul&gt; &gt;(std::__1::tuple&lt;WebCore::NetworkLoadMetrics&gt;&amp;&amp;, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics&amp;&amp;))+0x17 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x2f4d847)
    #50 0x132f47652 in void IPC::handleMessage&lt;Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics&amp;&amp;)&gt;(IPC::Connection&amp;, IPC::Decoder&amp;, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics&amp;&amp;))+0x152 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x2f47652)
    #51 0x132f469b9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&amp;, IPC::Decoder&amp;)+0x1f9 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x2f469b9)
    #52 0x132627b5e in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&amp;, IPC::Decoder&amp;)+0x10e (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x2627b5e)
    #53 0x133078e75 in IPC::Connection::dispatchMessage(IPC::Decoder&amp;)+0x275 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x3078e75)
    #54 0x133079384 in IPC::Connection::dispatchMessage(std::__1::unique_ptr&lt;IPC::Decoder, std::__1::default_delete&lt;IPC::Decoder&gt; &gt;)+0x2f4 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x3079384)
    #55 0x133079c94 in IPC::Connection::dispatchOneIncomingMessage()+0x184 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x3079c94)
    #56 0x133096100 in IPC::Connection::enqueueIncomingMessage(std::__1::unique_ptr&lt;IPC::Decoder, std::__1::default_delete&lt;IPC::Decoder&gt; &gt;)::$_17::operator()() const+0x10 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x3096100)
    #57 0x13309608c in WTF::Detail::CallableWrapper&lt;IPC::Connection::enqueueIncomingMessage(std::__1::unique_ptr&lt;IPC::Decoder, std::__1::default_delete&lt;IPC::Decoder&gt; &gt;)::$_17, void&gt;::call()+0xc (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x309608c)
    #58 0x163b45a3e in WTF::Function&lt;void ()&gt;::operator()() const+0x3e (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x3da3e)
    #59 0x163c0ac48 in WTF::RunLoop::performWork()+0x238 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x102c48)
    #60 0x163c0e5ca in WTF::RunLoop::performWork(void*)+0xba (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1065ca)
    #61 0x7fff205192bb in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__+0x10 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x802bb)
    #62 0x7fff20519223 in __CFRunLoopDoSource0+0xb3 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x80223)
    #63 0x7fff20518fa3 in __CFRunLoopDoSources0+0xf1 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x7ffa3)
    #64 0x7fff205179cb in __CFRunLoopRun+0x37c (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x7e9cb)
    #65 0x7fff20516f8b in CFRunLoopRunSpecific+0x232 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x7df8b)
    #66 0x7fff212a8606 in -[NSRunLoop(NSRunLoop) runMode:beforeDate:]+0xd3 (/System/Library/Frameworks/Foundation.framework/Versions/C/Foundation:x86_64+0x60606)
    #67 0x7fff213364d0 in -[NSRunLoop(NSRunLoop) run]+0x4b (/System/Library/Frameworks/Foundation.framework/Versions/C/Foundation:x86_64+0xee4d0)
    #68 0x7fff2017038c in _xpc_objc_main+0x338 (/usr/lib/system/libxpc.dylib:x86_64+0x1538c)
    #69 0x7fff2016fcd2 in xpc_main+0x73 (/usr/lib/system/libxpc.dylib:x86_64+0x14cd2)
    #70 0x130db7419 in WebKit::XPCServiceMain(int, char const**)+0x439 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0xdb7419)
    #71 0x133043b08 in WKXPCServiceMain+0x8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/WebKit.framework/Versions/A/WebKit:x86_64+0x3043b08)
    #72 0x10804ae98 in main+0x8 (/Users/chrome-bot/clusterfuzz/bot/builds/chrome-ios-webkit-to-fuzz_ios-webkit-to-fuzz_cb292771138f3c7c4bb12f2df778e2b1c42b4cd7/revisions/WebKitMacOS/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x100003e98)
    #73 0x7fff2043cf3c in start+0x0 (/usr/lib/system/libdyld.dylib:x86_64+0x15f3c)
==83355==Register values:
rax = 0x0000000000000001  rbx = 0x0000000000000008  rcx = 0x0000100000000001  rdx = 0x0000000000000000
rdi = 0x0000000000000008  rsi = 0x0000000000000000  rbp = 0x00007ffee7bb3eb0  rsp = 0x00007ffee7bb3eb0
 r8 = 0x0000100000000000   r9 = 0x0000000000000000  r10 = 0xffffffffffffffff  r11 = 0x00001f1ee7b8b068
r12 = 0x00007ffee7bb3f60  r13 = 0x00007ffee7bb3f60  r14 = 0x0000000000000000  r15 = 0x00007ffee7bb3f40
=====================================
Clusterfuzz-id: 4812230710460416</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1911132</commentid>
    <comment_count>1</comment_count>
    <who name="Radar WebKit Bug Importer">webkit-bug-importer</who>
    <bug_when>2022-11-08 15:23:55 -0800</bug_when>
    <thetext>&lt;rdar://problem/102112165&gt;</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1911969</commentid>
    <comment_count>2</comment_count>
    <who name="Ryosuke Niwa">rniwa</who>
    <bug_when>2022-11-12 02:12:54 -0800</bug_when>
    <thetext>This is a clean nullptr crash without any security implications.</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1911971</commentid>
    <comment_count>3</comment_count>
    <who name="Ryosuke Niwa">rniwa</who>
    <bug_when>2022-11-12 02:16:14 -0800</bug_when>
    <thetext>Pull request: https://github.com/WebKit/WebKit/pull/6424</thetext>
  </long_desc><long_desc isprivate="0" >
    <commentid>1912036</commentid>
    <comment_count>4</comment_count>
    <who name="EWS">ews-feeder</who>
    <bug_when>2022-11-12 15:11:03 -0800</bug_when>
    <thetext>Committed 256613@main (d44b5de990f9): &lt;https://commits.webkit.org/256613@main&gt;

Reviewed commits have been landed. Closing PR #6424 and removing active labels.</thetext>
  </long_desc>
      
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            <date>2022-11-08 15:23:39 -0800</date>
            <delta_ts>2022-11-08 15:23:39 -0800</delta_ts>
            <desc>Minimal test case</desc>
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