<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>[188298] trunk/Source/WebCore</title>
</head>
<body>
<style type="text/css"><!--
#msg dl.meta { border: 1px #006 solid; background: #369; padding: 6px; color: #fff; }
#msg dl.meta dt { float: left; width: 6em; font-weight: bold; }
#msg dt:after { content:':';}
#msg dl, #msg dt, #msg ul, #msg li, #header, #footer, #logmsg { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; }
#msg dl a { font-weight: bold}
#msg dl a:link { color:#fc3; }
#msg dl a:active { color:#ff0; }
#msg dl a:visited { color:#cc6; }
h3 { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; font-weight: bold; }
#msg pre { overflow: auto; background: #ffc; border: 1px #fa0 solid; padding: 6px; }
#logmsg { background: #ffc; border: 1px #fa0 solid; padding: 1em 1em 0 1em; }
#logmsg p, #logmsg pre, #logmsg blockquote { margin: 0 0 1em 0; }
#logmsg p, #logmsg li, #logmsg dt, #logmsg dd { line-height: 14pt; }
#logmsg h1, #logmsg h2, #logmsg h3, #logmsg h4, #logmsg h5, #logmsg h6 { margin: .5em 0; }
#logmsg h1:first-child, #logmsg h2:first-child, #logmsg h3:first-child, #logmsg h4:first-child, #logmsg h5:first-child, #logmsg h6:first-child { margin-top: 0; }
#logmsg ul, #logmsg ol { padding: 0; list-style-position: inside; margin: 0 0 0 1em; }
#logmsg ul { text-indent: -1em; padding-left: 1em; }#logmsg ol { text-indent: -1.5em; padding-left: 1.5em; }
#logmsg > ul, #logmsg > ol { margin: 0 0 1em 0; }
#logmsg pre { background: #eee; padding: 1em; }
#logmsg blockquote { border: 1px solid #fa0; border-left-width: 10px; padding: 1em 1em 0 1em; background: white;}
#logmsg dl { margin: 0; }
#logmsg dt { font-weight: bold; }
#logmsg dd { margin: 0; padding: 0 0 0.5em 0; }
#logmsg dd:before { content:'\00bb';}
#logmsg table { border-spacing: 0px; border-collapse: collapse; border-top: 4px solid #fa0; border-bottom: 1px solid #fa0; background: #fff; }
#logmsg table th { text-align: left; font-weight: normal; padding: 0.2em 0.5em; border-top: 1px dotted #fa0; }
#logmsg table td { text-align: right; border-top: 1px dotted #fa0; padding: 0.2em 0.5em; }
#logmsg table thead th { text-align: center; border-bottom: 1px solid #fa0; }
#logmsg table th.Corner { text-align: left; }
#logmsg hr { border: none 0; border-top: 2px dashed #fa0; height: 1px; }
#header, #footer { color: #fff; background: #636; border: 1px #300 solid; padding: 6px; }
#patch { width: 100%; }
#patch h4 {font-family: verdana,arial,helvetica,sans-serif;font-size:10pt;padding:8px;background:#369;color:#fff;margin:0;}
#patch .propset h4, #patch .binary h4 {margin:0;}
#patch pre {padding:0;line-height:1.2em;margin:0;}
#patch .diff {width:100%;background:#eee;padding: 0 0 10px 0;overflow:auto;}
#patch .propset .diff, #patch .binary .diff {padding:10px 0;}
#patch span {display:block;padding:0 10px;}
#patch .modfile, #patch .addfile, #patch .delfile, #patch .propset, #patch .binary, #patch .copfile {border:1px solid #ccc;margin:10px 0;}
#patch ins {background:#dfd;text-decoration:none;display:block;padding:0 10px;}
#patch del {background:#fdd;text-decoration:none;display:block;padding:0 10px;}
#patch .lines, .info {color:#888;background:#fff;}
--></style>
<div id="msg">
<dl class="meta">
<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/188298">188298</a></dd>
<dt>Author</dt> <dd>zalan@apple.com</dd>
<dt>Date</dt> <dd>2015-08-11 14:50:32 -0700 (Tue, 11 Aug 2015)</dd>
</dl>
<h3>Log Message</h3>
<pre>Invalid FrameView::m_viewportRenderer after layout is finished.
https://bugs.webkit.org/show_bug.cgi?id=147848
rdar://problem/22205197
Reviewed by Simon Fraser.
We cache the current viewport renderer (FrameView::m_viewportRenderer) right before layout.
It gets dereferenced later when layout is finished to update the overflow status.
If the viewport renderer gets destroyed during layout, we end up with a dangling pointer.
This patch replaces the pointer caching with type caching (none, body, document).
Unable to construct a test case.</pre>
<h3>Modified Paths</h3>
<ul>
<li><a href="#trunkSourceWebCoreChangeLog">trunk/Source/WebCore/ChangeLog</a></li>
<li><a href="#trunkSourceWebCorepageFrameViewcpp">trunk/Source/WebCore/page/FrameView.cpp</a></li>
<li><a href="#trunkSourceWebCorepageFrameViewh">trunk/Source/WebCore/page/FrameView.h</a></li>
</ul>
</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunkSourceWebCoreChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/ChangeLog (188297 => 188298)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/ChangeLog 2015-08-11 21:42:05 UTC (rev 188297)
+++ trunk/Source/WebCore/ChangeLog 2015-08-11 21:50:32 UTC (rev 188298)
</span><span class="lines">@@ -1,3 +1,18 @@
</span><ins>+2015-08-11 Zalan Bujtas <zalan@apple.com>
+
+ Invalid FrameView::m_viewportRenderer after layout is finished.
+ https://bugs.webkit.org/show_bug.cgi?id=147848
+ rdar://problem/22205197
+
+ Reviewed by Simon Fraser.
+
+ We cache the current viewport renderer (FrameView::m_viewportRenderer) right before layout.
+ It gets dereferenced later when layout is finished to update the overflow status.
+ If the viewport renderer gets destroyed during layout, we end up with a dangling pointer.
+ This patch replaces the pointer caching with type caching (none, body, document).
+
+ Unable to construct a test case.
+
</ins><span class="cx"> 2015-08-11 Brent Fulgham <bfulgham@apple.com>
</span><span class="cx">
</span><span class="cx"> [Win] Switch Windows build to Visual Studio 2015
</span></span></pre></div>
<a id="trunkSourceWebCorepageFrameViewcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/page/FrameView.cpp (188297 => 188298)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/page/FrameView.cpp 2015-08-11 21:42:05 UTC (rev 188297)
+++ trunk/Source/WebCore/page/FrameView.cpp 2015-08-11 21:50:32 UTC (rev 188298)
</span><span class="lines">@@ -172,7 +172,6 @@
</span><span class="cx"> , m_baseBackgroundColor(Color::white)
</span><span class="cx"> , m_mediaType("screen")
</span><span class="cx"> , m_overflowStatusDirty(true)
</span><del>- , m_viewportRenderer(nullptr)
</del><span class="cx"> , m_wasScrolledByUser(false)
</span><span class="cx"> , m_inProgrammaticScroll(false)
</span><span class="cx"> , m_safeToPropagateScrollToParent(true)
</span><span class="lines">@@ -621,18 +620,19 @@
</span><span class="cx"> IntSize FrameView::contentsSizeRespectingOverflow() const
</span><span class="cx"> {
</span><span class="cx"> RenderView* renderView = this->renderView();
</span><del>- if (!renderView || !m_viewportRenderer || !is<RenderBox>(m_viewportRenderer) || !frame().isMainFrame())
</del><ins>+ auto* viewportRenderer = this->viewportRenderer();
+ if (!renderView || !is<RenderBox>(viewportRenderer) || !frame().isMainFrame())
</ins><span class="cx"> return contentsSize();
</span><span class="cx">
</span><span class="cx"> ASSERT(frame().view() == this);
</span><span class="cx">
</span><span class="cx"> FloatRect contentRect = renderView->unscaledDocumentRect();
</span><del>- RenderBox& viewportRendererBox = downcast<RenderBox>(*m_viewportRenderer);
</del><ins>+ RenderBox& viewportRendererBox = downcast<RenderBox>(*viewportRenderer);
</ins><span class="cx">
</span><del>- if (m_viewportRenderer->style().overflowX() == OHIDDEN)
</del><ins>+ if (viewportRendererBox.style().overflowX() == OHIDDEN)
</ins><span class="cx"> contentRect.setWidth(std::min<float>(contentRect.width(), viewportRendererBox.frameRect().width()));
</span><span class="cx">
</span><del>- if (m_viewportRenderer->style().overflowY() == OHIDDEN)
</del><ins>+ if (viewportRendererBox.style().overflowY() == OHIDDEN)
</ins><span class="cx"> contentRect.setHeight(std::min<float>(contentRect.height(), viewportRendererBox.frameRect().height()));
</span><span class="cx">
</span><span class="cx"> if (renderView->hasTransform())
</span><span class="lines">@@ -641,7 +641,7 @@
</span><span class="cx"> return IntSize(contentRect.size());
</span><span class="cx"> }
</span><span class="cx">
</span><del>-void FrameView::applyOverflowToViewport(RenderElement* renderer, ScrollbarMode& hMode, ScrollbarMode& vMode)
</del><ins>+void FrameView::applyOverflowToViewport(const RenderElement& renderer, ScrollbarMode& hMode, ScrollbarMode& vMode)
</ins><span class="cx"> {
</span><span class="cx"> // Handle the overflow:hidden/scroll case for the body/html elements. WinIE treats
</span><span class="cx"> // overflow:hidden and overflow:scroll on <body> as applying to the document's
</span><span class="lines">@@ -654,13 +654,13 @@
</span><span class="cx">
</span><span class="cx"> bool overrideHidden = frame().isMainFrame() && ((frame().frameScaleFactor() > 1) || headerHeight() || footerHeight());
</span><span class="cx">
</span><del>- EOverflow overflowX = renderer->style().overflowX();
- EOverflow overflowY = renderer->style().overflowY();
</del><ins>+ EOverflow overflowX = renderer.style().overflowX();
+ EOverflow overflowY = renderer.style().overflowY();
</ins><span class="cx">
</span><del>- if (is<RenderSVGRoot>(*renderer)) {
</del><ins>+ if (is<RenderSVGRoot>(renderer)) {
</ins><span class="cx"> // FIXME: evaluate if we can allow overflow for these cases too.
</span><span class="cx"> // Overflow is always hidden when stand-alone SVG documents are embedded.
</span><del>- if (downcast<RenderSVGRoot>(*renderer).isEmbeddedThroughFrameContainingSVGDocument()) {
</del><ins>+ if (downcast<RenderSVGRoot>(renderer).isEmbeddedThroughFrameContainingSVGDocument()) {
</ins><span class="cx"> overflowX = OHIDDEN;
</span><span class="cx"> overflowY = OHIDDEN;
</span><span class="cx"> }
</span><span class="lines">@@ -701,8 +701,6 @@
</span><span class="cx"> // Don't set it at all. Values of OPAGEDX and OPAGEDY are handled by applyPaginationToViewPort().
</span><span class="cx"> ;
</span><span class="cx"> }
</span><del>-
- m_viewportRenderer = renderer;
</del><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> void FrameView::applyPaginationToViewport()
</span><span class="lines">@@ -733,7 +731,7 @@
</span><span class="cx">
</span><span class="cx"> void FrameView::calculateScrollbarModesForLayout(ScrollbarMode& hMode, ScrollbarMode& vMode, ScrollbarModesCalculationStrategy strategy)
</span><span class="cx"> {
</span><del>- m_viewportRenderer = nullptr;
</del><ins>+ m_viewportRendererType = ViewportRendererType::None;
</ins><span class="cx">
</span><span class="cx"> const HTMLFrameOwnerElement* owner = frame().ownerElement();
</span><span class="cx"> if (owner && (owner->scrollingMode() == ScrollbarAlwaysOff)) {
</span><span class="lines">@@ -750,24 +748,47 @@
</span><span class="cx"> vMode = ScrollbarAlwaysOff;
</span><span class="cx"> }
</span><span class="cx">
</span><del>- if (!m_layoutRoot) {
- Document* document = frame().document();
- auto documentElement = document->documentElement();
- RenderElement* rootRenderer = documentElement ? documentElement->renderer() : nullptr;
- auto* body = document->bodyOrFrameset();
- if (body && body->renderer()) {
- if (is<HTMLFrameSetElement>(*body) && !frameFlatteningEnabled()) {
- vMode = ScrollbarAlwaysOff;
- hMode = ScrollbarAlwaysOff;
- } else if (is<HTMLBodyElement>(*body)) {
- // It's sufficient to just check the X overflow,
- // since it's illegal to have visible in only one direction.
- RenderElement* o = rootRenderer->style().overflowX() == OVISIBLE && is<HTMLHtmlElement>(*document->documentElement()) ? body->renderer() : rootRenderer;
- applyOverflowToViewport(o, hMode, vMode);
</del><ins>+ if (m_layoutRoot)
+ return;
+
+ auto* document = frame().document();
+ if (!document)
+ return;
+
+ auto documentElement = document->documentElement();
+ if (!documentElement)
+ return;
+
+ auto* bodyOrFrameset = document->bodyOrFrameset();
+ auto* rootRenderer = documentElement->renderer();
+ if (!bodyOrFrameset || !bodyOrFrameset->renderer()) {
+ if (rootRenderer) {
+ applyOverflowToViewport(*rootRenderer, hMode, vMode);
+ m_viewportRendererType = ViewportRendererType::Document;
+ }
+ return;
+ }
+
+ if (is<HTMLFrameSetElement>(*bodyOrFrameset) && !frameFlatteningEnabled()) {
+ vMode = ScrollbarAlwaysOff;
+ hMode = ScrollbarAlwaysOff;
+ return;
+ }
+
+ if (is<HTMLBodyElement>(*bodyOrFrameset) && rootRenderer) {
+ // It's sufficient to just check the X overflow,
+ // since it's illegal to have visible in only one direction.
+ if (rootRenderer->style().overflowX() == OVISIBLE && is<HTMLHtmlElement>(documentElement)) {
+ auto* bodyRenderer = bodyOrFrameset->renderer();
+ if (bodyRenderer) {
+ applyOverflowToViewport(*bodyRenderer, hMode, vMode);
+ m_viewportRendererType = ViewportRendererType::Body;
</ins><span class="cx"> }
</span><del>- } else if (rootRenderer)
- applyOverflowToViewport(rootRenderer, hMode, vMode);
- }
</del><ins>+ } else {
+ applyOverflowToViewport(*rootRenderer, hMode, vMode);
+ m_viewportRendererType = ViewportRendererType::Document;
+ }
+ }
</ins><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> void FrameView::willRecalcStyle()
</span><span class="lines">@@ -3263,9 +3284,37 @@
</span><span class="cx"> setNeedsLayout();
</span><span class="cx"> }
</span><span class="cx">
</span><ins>+RenderElement* FrameView::viewportRenderer() const
+{
+ if (m_viewportRendererType == ViewportRendererType::None)
+ return nullptr;
+
+ auto* document = frame().document();
+ if (!document)
+ return nullptr;
+
+ if (m_viewportRendererType == ViewportRendererType::Document) {
+ auto* documentElement = document->documentElement();
+ if (!documentElement)
+ return nullptr;
+ return documentElement->renderer();
+ }
+
+ if (m_viewportRendererType == ViewportRendererType::Body) {
+ auto* body = document->body();
+ if (!body)
+ return nullptr;
+ return body->renderer();
+ }
+
+ ASSERT_NOT_REACHED();
+ return nullptr;
+}
+
</ins><span class="cx"> void FrameView::updateOverflowStatus(bool horizontalOverflow, bool verticalOverflow)
</span><span class="cx"> {
</span><del>- if (!m_viewportRenderer)
</del><ins>+ auto* viewportRenderer = this->viewportRenderer();
+ if (!viewportRenderer)
</ins><span class="cx"> return;
</span><span class="cx">
</span><span class="cx"> if (m_overflowStatusDirty) {
</span><span class="lines">@@ -3284,7 +3333,7 @@
</span><span class="cx">
</span><span class="cx"> RefPtr<OverflowEvent> overflowEvent = OverflowEvent::create(horizontalOverflowChanged, horizontalOverflow,
</span><span class="cx"> verticalOverflowChanged, verticalOverflow);
</span><del>- overflowEvent->setTarget(m_viewportRenderer->element());
</del><ins>+ overflowEvent->setTarget(viewportRenderer->element());
</ins><span class="cx">
</span><span class="cx"> frame().document()->enqueueOverflowEvent(overflowEvent.release());
</span><span class="cx"> }
</span></span></pre></div>
<a id="trunkSourceWebCorepageFrameViewh"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/page/FrameView.h (188297 => 188298)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/page/FrameView.h 2015-08-11 21:42:05 UTC (rev 188297)
+++ trunk/Source/WebCore/page/FrameView.h 2015-08-11 21:50:32 UTC (rev 188298)
</span><span class="lines">@@ -594,7 +594,7 @@
</span><span class="cx">
</span><span class="cx"> virtual void scrollPositionChangedViaPlatformWidgetImpl(const IntPoint& oldPosition, const IntPoint& newPosition) override;
</span><span class="cx">
</span><del>- void applyOverflowToViewport(RenderElement*, ScrollbarMode& hMode, ScrollbarMode& vMode);
</del><ins>+ void applyOverflowToViewport(const RenderElement&, ScrollbarMode& hMode, ScrollbarMode& vMode);
</ins><span class="cx"> void applyPaginationToViewport();
</span><span class="cx">
</span><span class="cx"> void updateOverflowStatus(bool horizontalOverflow, bool verticalOverflow);
</span><span class="lines">@@ -675,6 +675,8 @@
</span><span class="cx"> void removeFromAXObjectCache();
</span><span class="cx"> void notifyWidgets(WidgetNotification);
</span><span class="cx">
</span><ins>+ RenderElement* viewportRenderer() const;
+
</ins><span class="cx"> HashSet<Widget*> m_widgetsInRenderTree;
</span><span class="cx">
</span><span class="cx"> static double sCurrentPaintTimeStamp; // used for detecting decoded resource thrash in the cache
</span><span class="lines">@@ -718,8 +720,9 @@
</span><span class="cx">
</span><span class="cx"> bool m_overflowStatusDirty;
</span><span class="cx"> bool m_horizontalOverflow;
</span><del>- bool m_verticalOverflow;
- RenderElement* m_viewportRenderer;
</del><ins>+ bool m_verticalOverflow;
+ enum class ViewportRendererType { None, Document, Body };
+ ViewportRendererType m_viewportRendererType { ViewportRendererType::None };
</ins><span class="cx">
</span><span class="cx"> Pagination m_pagination;
</span><span class="cx">
</span></span></pre>
</div>
</div>
</body>
</html>