Created attachment 263277 [details] Test Load this with debug WebKit: <!DOCTYPE html> <textarea autofocus></textarea> <script> document.designMode = 'on'; document.execCommand("selectAll", false, null); </script> <body hidden> <li> <script> document.execCommand("selectAll", false, null); document.execCommand("cut", true , null); document.execCommand("insertParagraph", true , null); </script> Backtrace: ASSERTION FAILED: renderer() ../../Source/WebCore/html/HTMLTextAreaElement.cpp(341) : void WebCore::HTMLTextAreaElement::updateValue() const Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fff8effd700 (LWP 27716)] 0x00007fffec497eda in WTFCrash () at ../../Source/WTF/wtf/Assertions.cpp:321 321 *(int *)(uintptr_t)0xbbadbeef = 0; (gdb) bt #0 0x00007fffec497eda in WTFCrash () at ../../Source/WTF/wtf/Assertions.cpp:321 #1 0x00007ffff2bf0a0e in WebCore::HTMLTextAreaElement::updateValue (this=0x7fffd5bb6000) at ../../Source/WebCore/html/HTMLTextAreaElement.cpp:341 #2 0x00007ffff2bf0ace in WebCore::HTMLTextAreaElement::value (this=0x7fffd5bb6000) at ../../Source/WebCore/html/HTMLTextAreaElement.cpp:351 #3 0x00007ffff2bf14c6 in WebCore::HTMLTextAreaElement::tooLong (this=0x7fffd5bb6000) at ../../Source/WebCore/html/HTMLTextAreaElement.cpp:466 #4 0x00007ffff2b2d593 in WebCore::FormAssociatedElement::valid (this=0x7fffd5bb6068) at ../../Source/WebCore/html/FormAssociatedElement.cpp:218 #5 0x00007ffff2b6ac91 in WebCore::HTMLFormControlElement::updateValidity (this=0x7fffd5bb6000) at ../../Source/WebCore/html/HTMLFormControlElement.cpp:497 #6 0x00007ffff2bf0503 in WebCore::HTMLTextAreaElement::subtreeHasChanged (this=0x7fffd5bb6000) at ../../Source/WebCore/html/HTMLTextAreaElement.cpp:282 #7 0x00007ffff2bf2e97 in WebCore::HTMLTextFormControlElement::didEditInnerTextValue (this=0x7fffd5bb6000) at ../../Source/WebCore/html/HTMLTextFormControlElement.cpp:111 #8 0x00007ffff2a5fdd7 in WebCore::notifyTextFromControls (startRoot=0x7fffd5be24e0, endRoot=0x7fffd5be24e0) at ../../Source/WebCore/editing/Editor.cpp:1002 #9 0x00007ffff2a6018b in WebCore::Editor::appliedEditing (this=0x7fffd5aec000, cmd=...) at ../../Source/WebCore/editing/Editor.cpp:1025 #10 0x00007ffff2acf0c0 in WebCore::TypingCommand::typingAddedToOpenCommand (this=0x7fffd5aa4000, commandTypeForAddedTyping=WebCore::TypingCommand::InsertParagraphSeparator) at ../../Source/WebCore/editing/TypingCommand.cpp:359 #11 0x00007ffff2acf45e in WebCore::TypingCommand::insertParagraphSeparator (this=0x7fffd5aa4000) at ../../Source/WebCore/editing/TypingCommand.cpp:399 #12 0x00007ffff2acebcc in WebCore::TypingCommand::doApply (this=0x7fffd5aa4000) at ../../Source/WebCore/editing/TypingCommand.cpp:275 #13 0x00007ffff2a2bd72 in WebCore::CompositeEditCommand::apply (this=0x7fffd5aa4000) at ../../Source/WebCore/editing/CompositeEditCommand.cpp:229 #14 0x00007ffff2a2bb23 in WebCore::applyCommand (command=...) at ../../Source/WebCore/editing/CompositeEditCommand.cpp:188 #15 0x00007ffff2ace7de in WebCore::TypingCommand::insertParagraphSeparator (document=..., options=0) at ../../Source/WebCore/editing/TypingCommand.cpp:222 #16 0x00007ffff2a76a1c in WebCore::executeInsertParagraph (frame=...) at ../../Source/WebCore/editing/EditorCommand.cpp:524 #17 0x00007ffff2a7a5ca in WebCore::Editor::Command::execute (this=0x7fffffffb920, parameter=..., triggeringEvent=0x0) at ../../Source/WebCore/editing/EditorCommand.cpp:1704 #18 0x00007ffff28df7f7 in WebCore::Document::execCommand (this=0x7fffd581ea00, commandName=..., userInterface=true, value=...) at ../../Source/WebCore/dom/Document.cpp:4657 #19 0x00007ffff3a87d9f in WebCore::jsDocumentPrototypeFunctionExecCommand (state=0x7fffffffb9f0) at DerivedSources/WebCore/JSDocument.cpp:5101 #20 0x00007fff953e00c8 in ?? () #21 0x00007fffffffba70 in ?? () #22 0x00007fffec440591 in llint_entry () from /home/reni/data/REPOS/fuzztargets/webkit/WebKitBuild/Debug/lib/libjavascriptcoregtk-4.0.so.18
This problem does not reproduce under r204037. If you believe there is still a problem, please reopen the bug and provide a revised test case.