Changeset 259769 in webkit

Timestamp:

Apr 8, 2020, 5:38:27 PM (6 years ago)

Author:

Alan Coon

Message:

Cherry-pick r259766. rdar://problem/61487124

REGRESSION (r258525): Occasional crashes under TextManipulationController::observeParagraphs
​https://bugs.webkit.org/show_bug.cgi?id=210215
<rdar://problem/61362512>

Reviewed by Darin Adler.

In the case where startOfParagraph or endOfParagraph return a null Position, we end up crashing under
TextManipulationController::observeParagraphs while creating ParagraphContentIterator, which expects non-null
Positions because it dereferences the result of makeBoundaryPoint.

Avoid this crash for now by bailing if either the start or end positions are null. Tests to be added in a
followup patch.

• editing/TextManipulationController.cpp: (WebCore::TextManipulationController::observeParagraphs):

git-svn-id: ​https://svn.webkit.org/repository/webkit/trunk@259766 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Location:

branches/safari-610.1.9-branch/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• editing/TextManipulationController.cpp (modified) (1 diff)

branches/safari-610.1.9-branch/Source/WebCore/ChangeLog

@@ +1 @@
+2020-04-08  Alan Coon  <alancoon@apple.com>
+
+        Cherry-pick r259766. rdar://problem/61487124
+
+    REGRESSION (r258525): Occasional crashes under TextManipulationController::observeParagraphs
+    https://bugs.webkit.org/show_bug.cgi?id=210215
+    <rdar://problem/61362512>
+    
+    Reviewed by Darin Adler.
+    
+    In the case where `startOfParagraph` or `endOfParagraph` return a null `Position`, we end up crashing under
+    TextManipulationController::observeParagraphs while creating `ParagraphContentIterator`, which expects non-null
+    `Position`s because it dereferences the result of `makeBoundaryPoint`.
+    
+    Avoid this crash for now by bailing if either the start or end positions are null. Tests to be added in a
+    followup patch.
+    
+    * editing/TextManipulationController.cpp:
+    (WebCore::TextManipulationController::observeParagraphs):
+    
+    
+    git-svn-id: https://svn.webkit.org/repository/webkit/trunk@259766 268f45cc-cd09-0410-ab3c-d52691b4dbfc
+
+    2020-04-08  Wenson Hsieh  <wenson_hsieh@apple.com>
+
+            REGRESSION (r258525): Occasional crashes under TextManipulationController::observeParagraphs
+            https://bugs.webkit.org/show_bug.cgi?id=210215
+            <rdar://problem/61362512>
+
+            Reviewed by Darin Adler.
+
+            In the case where `startOfParagraph` or `endOfParagraph` return a null `Position`, we end up crashing under
+            TextManipulationController::observeParagraphs while creating `ParagraphContentIterator`, which expects non-null
+            `Position`s because it dereferences the result of `makeBoundaryPoint`.
+
+            Avoid this crash for now by bailing if either the start or end positions are null. Tests to be added in a
+            followup patch.
+
+            * editing/TextManipulationController.cpp:
+            (WebCore::TextManipulationController::observeParagraphs):
+
 2020-04-07  Alan Coon  <alancoon@apple.com>
 

branches/safari-610.1.9-branch/Source/WebCore/editing/TextManipulationController.cpp

@@ -240 +240 @@
 void TextManipulationController::observeParagraphs(const Position& start, const Position& end)
 {
+    if (start.isNull() || end.isNull())
+        return;
+
     auto document = makeRefPtr(start.document());
     ASSERT(document);