RESOLVED FIXED 75593
null-check variable page before using it in FrameView::notifyPageThatContentAreaWillPaint. 
https://bugs.webkit.org/show_bug.cgi?id=75593
Summary null-check variable page before using it in FrameView::notifyPageThatContentA...
Yongjun Zhang
Reported 2012-01-04 17:57:00 PST
In FrameView::notifyPageThatContentAreaWillPaint(), we should null-check variable page, which is common usage pattern throughout the rest of FrameView.cpp.
Attachments
null-check variable 'page', to follow the usage pattern of m_frame->page() throughout the rest of FrameView.cpp. (1.26 KB, patch)
2012-01-04 18:03 PST, Yongjun Zhang 		no flags
DetailsFormatted DiffDiff
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Yongjun Zhang
Comment 1 2012-01-04 18:03:58 PST
Created attachment 121199 [details] null-check variable 'page', to follow the usage pattern of m_frame->page() throughout the rest of FrameView.cpp.
Yongjun Zhang
Comment 2 2012-01-04 18:06:43 PST
<rdar://problem/10603538>
Alexey Proskuryakov
Comment 3 2012-01-05 10:30:27 PST
Comment on attachment 121199 [details] null-check variable 'page', to follow the usage pattern of m_frame->page() throughout the rest of FrameView.cpp. There are several other places in FrameView.cpp that don't do the null check. It would be strange if a pageless frame were to be painted! Does this fix an actual crash?
Yongjun Zhang
Comment 4 2012-01-05 14:36:12 PST
(In reply to comment #3) > (From update of attachment 121199 [details]) > There are several other places in FrameView.cpp that don't do the null check. > > It would be strange if a pageless frame were to be painted! Does this fix an actual crash? It fixed a hard-to-reproduce crash in iOS.
Alexey Proskuryakov
Comment 5 2012-01-05 16:56:01 PST
Comment on attachment 121199 [details] null-check variable 'page', to follow the usage pattern of m_frame->page() throughout the rest of FrameView.cpp. I guess it's OK to add = another null check (there is enough confusion about when they are needed in this file already). It would be much better to find out why anyone would call notifyPageThatContentAreaWillPaint() when there is no page, and they are not painting, and fix that instead.
Yongjun Zhang
Comment 6 2012-01-05 17:13:57 PST
(In reply to comment #5) > (From update of attachment 121199 [details]) > I guess it's OK to add = another null check (there is enough confusion about when they are needed in this file already). > > It would be much better to find out why anyone would call notifyPageThatContentAreaWillPaint() when there is no page, and they are not painting, and fix that instead. thanks Alexey! Let's land this first and I will keep trying to find a reproducible case.
WebKit Review Bot
Comment 7 2012-01-05 18:13:44 PST
Comment on attachment 121199 [details] null-check variable 'page', to follow the usage pattern of m_frame->page() throughout the rest of FrameView.cpp. Clearing flags on attachment: 121199 Committed r104260: <http://trac.webkit.org/changeset/104260>
WebKit Review Bot
Comment 8 2012-01-05 18:13:49 PST
All reviewed patches have been landed. Closing bug.
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