Changeset 243908 in webkit

Timestamp:

Apr 4, 2019, 2:47:29 PM (7 years ago)

Author:

Simon Fraser

Message:

Fix rare crash under collectRelatedCoordinatedScrollingNodes()
​https://bugs.webkit.org/show_bug.cgi?id=196610
rdar://problem/49595426

Reviewed by Zalan Bujtas.

hasCompositedScrollableOverflow() doesn't check whether a layer is composited (it has
to report the right status before layers have been created), so collectRelatedCoordinatedScrollingNodes()
needs to check whether there's backing.

• rendering/RenderLayerCompositor.cpp:

(WebCore::collectRelatedCoordinatedScrollingNodes):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• rendering/RenderLayerCompositor.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-04-04  Simon Fraser  <simon.fraser@apple.com>
+
+        Fix rare crash under collectRelatedCoordinatedScrollingNodes()
+        https://bugs.webkit.org/show_bug.cgi?id=196610
+        rdar://problem/49595426
+
+        Reviewed by Zalan Bujtas.
+
+        hasCompositedScrollableOverflow() doesn't check whether a layer is composited (it has
+        to report the right status before layers have been created), so collectRelatedCoordinatedScrollingNodes()
+        needs to check whether there's backing.
+
+        * rendering/RenderLayerCompositor.cpp:
+        (WebCore::collectRelatedCoordinatedScrollingNodes):
+
 2019-04-04  Simon Fraser  <simon.fraser@apple.com>
 

trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp

@@ -2988 +2988 @@
         for (const auto* currLayer = layer.parent(); currLayer != compositedAncestor; currLayer = currLayer->parent()) {
             if (currLayer->hasCompositedScrollableOverflow()) {
-                auto scrollingNodeID = currLayer->backing()->scrollingNodeIDForRole(ScrollCoordinationRole::Scrolling);
+                auto scrollingNodeID = currLayer->isComposited() ? currLayer->backing()->scrollingNodeIDForRole(ScrollCoordinationRole::Scrolling) : 0;
                 if (scrollingNodeID)
                     overflowNodeData.append(scrollingNodeID);
                 else
-                    LOG(Scrolling, "Layer %p doesn't have scrolling node ID yet", &layer);
+                    LOG(Scrolling, "Layer %p isn't composited or doesn't have scrolling node ID yet", &layer);
             }
         }