Bug 181742 – REGRESSION (r226385?): Crash in com.apple.WebCore: WebCore::MediaQueryEvaluator::evaluate const + 32

• Status: RESOLVED
• Resolution: FIXED
• Component: CSS

[Antti Koivisto]

>  1 com.apple.WebCore              0x00bf2440 WebCore::MediaQueryEvaluator::evaluate(WebCore::MediaQueryExpression const&) const + 32
   2 com.apple.WebCore              0x00bf2278 WebCore::MediaQueryEvaluator::evaluate(WebCore::MediaQuerySet const&, WebCore::StyleResolver*) const + 344
   3 com.apple.WebCore              0x00bfdcf9 WebCore::RuleSet::addChildRules(WTF::Vector<WTF::RefPtr<WebCore::StyleRuleBase, WTF::DumbPtrTraits<WebCore::StyleRuleBase> >, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc> const&, WebCore::MediaQueryEvaluator const&, WebCore::StyleResolver*, bool) + 281
   4 com.apple.WebCore              0x00bfde71 WebCore::RuleSet::addRulesFromSheet(WebCore::StyleSheetContents&, WebCore::MediaQueryEvaluator const&, WebCore::StyleResolver*) + 145
   5 com.apple.WebCore              0x00be1fb7 WebCore::ElementRuleCollector::ElementRuleCollector(WebCore::Element const&, WebCore::DocumentRuleSets const&, WebCore::SelectorFilter const*) + 135
   6 com.apple.WebCore              0x00c0df0e WebCore::StyleResolver::styleForElement(WebCore::Element const&, WebCore::RenderStyle const*, WebCore::RenderStyle const*, WebCore::RuleMatchingBehavior, WebCore::SelectorFilter const*) + 798
   7 com.apple.WebCore              0x00caa22e WebCore::Document::styleForElementIgnoringPendingStylesheets(WebCore::Element&, WebCore::RenderStyle const*, WebCore::PseudoId) + 158
   8 com.apple.WebCore              0x00cdaefb WebCore::Element::resolveComputedStyle() + 699
   9 com.apple.WebCore              0x0007293a WebCore::Element::computedStyle(WebCore::PseudoId) + 186
  10 com.apple.WebCore              0x00e57a91 WebCore::HTMLTitleElement::computedTextWithDirection() + 33
  11 com.apple.WebCore              0x00e579ed WebCore::HTMLTitleElement::childrenChanged(WebCore::ContainerNode::ChildChange const&) + 29
  12 com.apple.WebCore              0x00c91d44 WebCore::ContainerNode::appendChildWithoutPreInsertionValidityCheck(WebCore::Node&) + 980
  13 com.apple.WebCore              0x00c93a65 WebCore::ContainerNode::replaceAllChildren(WTF::Ref<WebCore::Node, WTF::DumbPtrTraits<WebCore::Node> >&&) + 645
  14 com.apple.WebCore              0x00df1949 WebCore::HTMLElement::setInnerText(WTF::String const&) + 265
  15 com.apple.WebCore              0x0051b32e WebCore::setJSHTMLElementInnerText(JSC::ExecState*, long long, long long) + 334

[Antti Koivisto]

<rdar://problem/36334726>

[Antti Koivisto]

Created attachment 331494 [details]
patch

[David Kilzer (:ddkilzer)]

Comment on attachment 331494 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=331494&action=review

r=me, but maybe you want a review from Dean Jackson or another area expert.

> Source/WebCore/css/MediaQueryEvaluator.cpp:778
> +    if (!m_document)
> +        return m_fallbackResult;
> +
> +    Document& document = *m_document;
> +    auto* frame = document.frame();
> +    if (!frame || !frame->view() || !m_style)
>          return m_fallbackResult;

You could move the "!m_style" check to the first if statement to avoid a small amount of work:

    if (!m_document || !m_style)
        return m_fallbackResult;

[WebKit Commit Bot]

Comment on attachment 331494 [details]
patch

Clearing flags on attachment: 331494

Committed r227082: <https://trac.webkit.org/changeset/227082>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.