[webkit-changes] [WebKit/WebKit] b2ea0a: CRASH in MobileSafari at WebCore: WebCore::Region:...

[Jer Noble]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: b2ea0ac07abf198dfab2528af225eccd4928e8e6
      https://github.com/WebKit/WebKit/commit/b2ea0ac07abf198dfab2528af225eccd4928e8e6
  Author: Jer Noble <jer.noble at apple.com>
  Date:   2023-10-11 (Wed, 11 Oct 2023)

  Changed paths:
    M Source/WebKit/UIProcess/RemoteLayerTree/ios/RemoteLayerTreeViews.mm

  Log Message:
  -----------
  CRASH in MobileSafari at WebCore: WebCore::Region::intersects
https://bugs.webkit.org/show_bug.cgi?id=263038
rdar://116794024

Reviewed by John Wilander and Wenson Hsieh.

Crash logs indicate a new crash originating in `collectDescendantViewsInRect()`, where a null return from `RemoteLayerTreeNode::forCALayer(...)` is dereferenced without a null check. A null check was added to `collectDescendantViewsAtPoint()` in 268566 at main, and a similar null check will be added here.

Verified through code inspection that no additional unguarded uses of `RemoteLayerTreeNode::forCALayer(...)` remain after this change.

* Source/WebKit/UIProcess/RemoteLayerTree/ios/RemoteLayerTreeViews.mm:
(WebKit::collectDescendantViewsInRect):

Canonical link: https://commits.webkit.org/269225@main