Bug 214017 – Web content process hangs in AccessibilityRenderObject::setSelectedVisiblePositionRange in some corner cases.

• Status: RESOLVED
• Resolution: FIXED
• Component: New Bugs

[Andres Gonzalez]

Web content process hangs in AccessibilityRenderObject::setSelectedVisiblePositionRange in some corner cases.

[Andres Gonzalez]

<rdar://problem/63000006>

[Andres Gonzalez]

Relevant output from sample:

Sampling process 12998 for 3 seconds with 1 millisecond of run time between samples
Sampling completed, processing symbols...
Analysis of sampling com.apple.WebKit.WebContent.Development (pid 12998) every 1 millisecond
Process:         com.apple.WebKit.WebContent.Development [12998]
Path:            /System/Library/Frameworks/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.Development.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development
Load Address:    0x1058ec000
Identifier:      com.apple.WebKit.WebContent.Development

Call graph:
    2438 Thread_161694   DispatchQueue_1: com.apple.main-thread  (serial)
    + 2438 start  (in libdyld.dylib) + 1  [0x7fff6edd3221]
    +   2438 WebKit::XPCServiceMain(int, char const**)  (in WebKit) + 578  [0x7fff3e059439]
    +     2438 xpc_main  (in libxpc.dylib) + 437  [0x7fff6f046e54]
    +       2438 _xpc_objc_main  (in libxpc.dylib) + 760  [0x7fff6f04738b]
    +         2438 -[NSRunLoop(NSRunLoop) run]  (in Foundation) + 76  [0x7fff2d8fb6a3]
    +           2438 -[NSRunLoop(NSRunLoop) runMode:beforeDate:]  (in Foundation) + 212  [0x7fff2d86a5e0]
    +             2438 CFRunLoopRunSpecific  (in CoreFoundation) + 514  [0x7fff2ad9fe2b]
    +               2438 __CFRunLoopRun  (in CoreFoundation) + 1983  [0x7fff2ada0c58]
    +                 2438 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__  (in CoreFoundation) + 9  [0x7fff2addefcf]
    +                   2438 _dispatch_main_queue_callback_4CF  (in libdispatch.dylib) + 940  [0x7fff6ed882cd]
    +                     2438 _dispatch_client_callout  (in libdispatch.dylib) + 8  [0x7fff6ed7c10f]
    +                       2438 _dispatch_call_block_and_release  (in libdispatch.dylib) + 12  [0x7fff6ed7af2d]
    +                         2438 -[WebAccessibilityObjectWrapper _accessibilitySetValue:forAttribute:]  (in WebCore) + 440  [0x7fff3d89af38]
    +                           2438 WebCore::AccessibilityRenderObject::setSelectedVisiblePositionRange(WebCore::VisiblePositionRange const&) const  (in WebCore) + 945  [0x7fff3c903361]
    +                             2438 WebCore::FrameSelection::moveTo(WebCore::VisiblePosition const&, WebCore::EUserTriggered, WebCore::FrameSelection::CursorAlignOnScroll)  (in WebCore) + 298  [0x7fff3baa17da]
    +                               2438 WebCore::FrameSelection::setSelection(WebCore::VisibleSelection const&, WTF::OptionSet<WebCore::FrameSelection::SetSelectionOption>, WebCore::AXTextStateChangeIntent, WebCore::FrameSelection::CursorAlignOnScroll, WebCore::TextGranularity)  (in WebCore) + 525  [0x7fff3ccef9ad]
    +                                 2438 WebKit::WebPage::sendEditorStateUpdate()  (in WebKit) + 79  [0x7fff3e44011d]
    +                                   2438 WebKit::WebPage::editorState(WebKit::WebPage::ShouldPerformLayout) const  (in WebKit) + 1128  [0x7fff3e43801a]
    +                                     2438 WebKit::WebPage::getPlatformEditorState(WebCore::Frame&, WebKit::EditorState&) const  (in WebKit) + 787  [0x7fff3e2f9701]
    +                                       2438 WebCore::Editor::stringForCandidateRequest() const  (in WebCore) + 123  [0x7fff3cd0d4cb]
    +                                         1930 WebCore::wordRangeFromPosition(WebCore::VisiblePosition const&)  (in WebCore) + 198  [0x7fff3cd87de6]
...

[Andres Gonzalez]

Created attachment 403639 [details]
Patch

[chris fleizach]

Comment on attachment 403639 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=403639&action=review

> Source/WebCore/ChangeLog:12
> +        * accessibility/AccessibilityRenderObject.cpp:

any chance to test this?

[Andres Gonzalez]

Created attachment 403707 [details]
Patch

[EWS]

Committed r264037: <https://trac.webkit.org/changeset/264037>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 403707 [details].