Changeset 240896 in webkit

Timestamp:

Feb 2, 2019 10:35:42 AM (5 years ago)

Author:

ddkilzer@apple.com

Message:

Leak of WTF::StringImpl under SymbolImpl::createNullSymbol() (48 bytes) in com.apple.WebKit.WebContent running layout tests
<​https://webkit.org/b/193291>
<rdar://problem/46655953>

Reviewed by Keith Miller.

• wtf/text/SymbolImpl.h:

(WTF::SymbolImpl::~SymbolImpl): Fix the leak by implementing the
class destructor that calls StringImpl::deref() on m_owner.
Two of the three constructors leak the StringImpl when setting
m_owner, so we need to balance that by manually calling
deref().

Location:

trunk/Source/WTF

Files:

• ChangeLog (modified) (1 diff)
• wtf/text/SymbolImpl.h (modified) (1 diff)

trunk/Source/WTF/ChangeLog

@@ +1 @@
+2019-02-02  David Kilzer  <ddkilzer@apple.com>
+
+        Leak of WTF::StringImpl under SymbolImpl::createNullSymbol() (48 bytes) in com.apple.WebKit.WebContent running layout tests
+        <https://webkit.org/b/193291>
+        <rdar://problem/46655953>
+
+        Reviewed by Keith Miller.
+
+        * wtf/text/SymbolImpl.h:
+        (WTF::SymbolImpl::~SymbolImpl): Fix the leak by implementing the
+        class destructor that calls StringImpl::deref() on `m_owner`.
+        Two of the three constructors leak the StringImpl when setting
+        `m_owner`, so we need to balance that by manually calling
+        deref().
+
 2018-12-16  Darin Adler  <darin@apple.com>
 

trunk/Source/WTF/wtf/text/SymbolImpl.h

@@ -117 +117 @@
     }
 
+    ~SymbolImpl()
+    {
+        if (m_owner != StringImpl::empty())
+            m_owner->deref();
+        m_owner = nullptr;
+    }
+
     // The pointer to the owner string should be immediately following after the StringImpl layout,
     // since we would like to align the layout of SymbolImpl to the one of BufferSubstring StringImpl.