Bug 55290 – REGRESSION(r79398): Webkit crash on dojo theme tester page

• Status: RESOLVED
• Resolution: FIXED
• Component: HTML Editing

[Darth]

Browser crashes while looking at dojo theme tester.
Doesn't happen in nightly release r79303. Happens in all nightly beyond that.
Chromium 11.0.683.0 is also getting a renderer crash, might be due to the same.

[Alexey Proskuryakov]

Confirmed with nightly r79488. Suspecting <http://trac.webkit.org/r79398>.

0   com.apple.WebCore             	0x0000000100ef1e1d WebCore::Editor::selectionStartCSSPropertyValue(int) + 45
1   com.apple.WebCore             	0x0000000100efdc18 WebCore::valueStyle(WebCore::Frame*, int) + 24
2   com.apple.WebCore             	0x0000000100efdca6 WebCore::valueFontName(WebCore::Frame*, WebCore::Event*) + 22
3   com.apple.WebCore             	0x0000000100eff1df WebCore::Editor::Command::value(WebCore::Event*) const + 111
4   com.apple.WebCore             	0x0000000100e060c9 WebCore::Document::queryCommandValue(WTF::String const&) + 41
5   com.apple.WebCore             	0x00000001011d8c36 WebCore::jsDocumentPrototypeFunctionQueryCommandValue(JSC::ExecState*) + 278

[Alexey Proskuryakov]

<rdar://problem/9058070>

[Ryosuke Niwa]

(In reply to comment #1)
> Confirmed with nightly r79488. Suspecting <http://trac.webkit.org/r79398>.
> 
> 0   com.apple.WebCore                 0x0000000100ef1e1d WebCore::Editor::selectionStartCSSPropertyValue(int) + 45
> 1   com.apple.WebCore                 0x0000000100efdc18 WebCore::valueStyle(WebCore::Frame*, int) + 24
> 2   com.apple.WebCore                 0x0000000100efdca6 WebCore::valueFontName(WebCore::Frame*, WebCore::Event*) + 22
> 3   com.apple.WebCore                 0x0000000100eff1df WebCore::Editor::Command::value(WebCore::Event*) const + 111
> 4   com.apple.WebCore                 0x0000000100e060c9 WebCore::Document::queryCommandValue(WTF::String const&) + 41
> 5   com.apple.WebCore                 0x00000001011d8c36 WebCore::jsDocumentPrototypeFunctionQueryCommandValue(JSC::ExecState*) + 278

Oops!  Yes, it's missing a null check. http://trac.webkit.org/browser/trunk/Source/WebCore/editing/Editor.cpp#L1043

    RefPtr<EditingStyle> selectionStyle = selectionStartStyle();
	    if (!selectionStyle->style())
	        return String();

should be

    RefPtr<EditingStyle> selectionStyle = selectionStartStyle();
	    if (!selectionStyle || !selectionStyle->style())
	        return String();

instead.

[Ryosuke Niwa]

Created attachment 83937 [details]
fixes the bug

[Ryosuke Niwa]

This was an embarrassing bug :(

[WebKit Commit Bot]

Comment on attachment 83937 [details]
fixes the bug

Clearing flags on attachment: 83937

Committed r79794: <http://trac.webkit.org/changeset/79794>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Ryosuke Niwa]

*** Bug 55359 has been marked as a duplicate of this bug. ***