Bug 149302 – Null dereference loading Blink layout test fast/css/zoom-on-nested-scroll-crash.html

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Jon Honeycutt]

Created attachment 261436 [details]
crashing test

Null dereference loading Blink layout test fast/css/zoom-on-nested-scroll-crash.html.

Stack trace:

Crashed Thread:        0  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000028
Exception Note:        EXC_CORPSE_NOTIFY

VM Regions Near 0x28:
--> 
    __TEXT                 000000010bcc8000-000000010bcca000 [    8K] r-x/rwx SM=COW  /Users/USER/*/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.Development.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development

Application Specific Information:
CRASHING TEST: temp-tests/fast/css/zoom-on-nested-scroll-crash.html

Global Trace Buffer (reverse chronological seconds):
57.772360    CFNetwork                 	0x00007fff88d43b97 Explicitly setting CF cookie storage singleton
57.772701    CFNetwork                 	0x00007fff88d8f211 Explicitly setting cookie storage singleton

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   com.apple.WebCore             	0x000000011450e98b WebCore::RenderBox::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 491 (IntPoint.h:69)
1   com.apple.WebCore             	0x00000001144de4a1 WebCore::RenderBlock::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 145 (RenderObject.h:970)
2   com.apple.WebCore             	0x00000001145f2348 WebCore::RenderScrollbarPart::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 24 (RenderObject.h:969)
3   com.apple.WebCore             	0x0000000114540692 WebCore::RenderElement::setStyle(WTF::Ref<WebCore::RenderStyle>&&, WebCore::StyleDifference) + 594 (RenderElement.h:66)
4   com.apple.WebCore             	0x00000001145f0191 WebCore::RenderScrollbar::updateScrollbarPart(WebCore::ScrollbarPart) + 353 (Ref.h:55)
5   com.apple.WebCore             	0x00000001145f061e WebCore::RenderScrollbar::updateScrollbarParts() + 30 (RenderScrollbar.cpp:159)
6   com.apple.WebCore             	0x0000000114599c09 WebCore::RenderLayer::styleChanged(WebCore::StyleDifference, WebCore::RenderStyle const*) + 985 (RefPtr.h:75)
7   com.apple.WebCore             	0x00000001145b3f8e WebCore::RenderLayerModelObject::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 542 (RenderLayerModelObject.cpp:160)
8   com.apple.WebCore             	0x000000011450e7c2 WebCore::RenderBox::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 34 (Ref.h:120)
9   com.apple.WebCore             	0x00000001144de4a1 WebCore::RenderBlock::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 145 (RenderObject.h:970)
10  com.apple.WebCore             	0x00000001144fb49c WebCore::RenderBlockFlow::styleDidChange(WebCore::StyleDifference, WebCore::RenderStyle const*) + 28 (RenderObject.h:958)
11  com.apple.WebCore             	0x0000000114540692 WebCore::RenderElement::setStyle(WTF::Ref<WebCore::RenderStyle>&&, WebCore::StyleDifference) + 594 (RenderElement.h:66)
12  com.apple.WebCore             	0x00000001147f95cf WebCore::Style::resolveTree(WebCore::Element&, WebCore::RenderStyle&, WebCore::RenderTreePosition&, WebCore::Style::Change) + 1711 (Ref.h:55)
13  com.apple.WebCore             	0x00000001147f99c2 WebCore::Style::resolveTree(WebCore::Element&, WebCore::RenderStyle&, WebCore::RenderTreePosition&, WebCore::Style::Change) + 2722 (StyleResolveTree.cpp:827)
14  com.apple.WebCore             	0x00000001147f99c2 WebCore::Style::resolveTree(WebCore::Element&, WebCore::RenderStyle&, WebCore::RenderTreePosition&, WebCore::Style::Change) + 2722 (StyleResolveTree.cpp:827)
15  com.apple.WebCore             	0x00000001147f8f10 WebCore::Style::resolveTree(WebCore::Document&, WebCore::Style::Change) + 336 (StyleResolveTree.cpp:867)
16  com.apple.WebCore             	0x0000000113c39f7d WebCore::Document::recalcStyle(WebCore::Style::Change) + 285 (Document.cpp:1864)
17  com.apple.WebCore             	0x0000000113c45275 WebCore::Document::finishedParsing() + 405 (Frame.h:327)
18  com.apple.WebCore             	0x0000000113e71e05 WebCore::HTMLDocumentParser::prepareToStopParsing() + 165 (RefCounted.h:99)
19  com.apple.WebCore             	0x0000000113c7569a WebCore::DocumentWriter::end() + 58 (StdLibExtras.h:366)
20  com.apple.WebCore             	0x0000000113c5d9ec WebCore::DocumentLoader::finishedLoading(double) + 268 (ResourceErrorBase.h:42)
21  com.apple.WebCore             	0x0000000113a8e179 WebCore::CachedResource::checkNotify() + 153 (CachedResourceClientWalker.h:51)
22  com.apple.WebCore             	0x0000000113a8a433 WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) + 227 (CachedRawResource.cpp:104)
23  com.apple.WebCore             	0x0000000114805501 WebCore::SubresourceLoader::didFinishLoading(double) + 1153 (ResourceLoader.h:154)
24  com.apple.WebKit              	0x000000011234b98d WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::MessageDecoder&) + 561 (HandleMessage.h:16)
25  com.apple.WebKit              	0x00000001121251f1 IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::MessageDecoder, std::__1::default_delete<IPC::MessageDecoder> >) + 127 (memory:2636)
26  com.apple.WebKit              	0x0000000112127b4a IPC::Connection::dispatchOneMessage() + 126 (memory:2656)
27  com.apple.JavaScriptCore      	0x0000000113569985 WTF::RunLoop::performWork() + 437 (functional:1742)
28  com.apple.JavaScriptCore      	0x0000000113569d32 WTF::RunLoop::performWork(void*) + 34 (RunLoopCF.cpp:39)
29  com.apple.CoreFoundation      	0x00007fff949e2c01 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
30  com.apple.CoreFoundation      	0x00007fff949d4b1c __CFRunLoopDoSources0 + 556
31  com.apple.CoreFoundation      	0x00007fff949d403f __CFRunLoopRun + 927
32  com.apple.CoreFoundation      	0x00007fff949d3a38 CFRunLoopRunSpecific + 296
33  com.apple.HIToolbox           	0x00007fff88e673bd RunCurrentEventLoopInMode + 235
34  com.apple.HIToolbox           	0x00007fff88e67153 ReceiveNextEventCommon + 432
35  com.apple.HIToolbox           	0x00007fff88e66f93 _BlockUntilNextEventMatchingListInModeWithFilter + 71
36  com.apple.AppKit              	0x00007fff870b81e7 _DPSNextEvent + 1076
37  com.apple.AppKit              	0x00007fff8748490d -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454
38  com.apple.AppKit              	0x00007fff870ae0b8 -[NSApplication run] + 682
39  com.apple.AppKit              	0x00007fff87030396 NSApplicationMain + 1176
40  libxpc.dylib                  	0x00007fff8c70ff70 _xpc_objc_main + 793
41  libxpc.dylib                  	0x00007fff8c7116bf xpc_main + 494
42  com.apple.WebKit.WebContent.Development	0x000000010bcc9424 main + 409 (XPCServiceMain.Development.mm:187)
43  libdyld.dylib                 	0x00007fff93aa15ad start + 1

[Radar WebKit Bug Importer]

<rdar://problem/22747292>

[Jiewen Tan]

Created attachment 262663 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 262663 [details]
Patch

Clearing flags on attachment: 262663

Committed r190732: <http://trac.webkit.org/changeset/190732>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[alan]

By looking at the stacktrace, I think what the problem here is that RenderScrollbarPart does not create a render layer (requiresLayer() returns false) while we assume that a box with overflow clip always has a layer. This unexpected behavior will surely show up at other places too.
I'd rather check explicitly for scrollbarpart here and assert on layer(), so that we can catch other offenders.