Lock EnsureConfigured to prevent initialization issues in JsonTypeInfo (

#68605) * Lock EnsureConfigured to prevent initialization issues in JsonTypeInfo * do not use this for lock, ensure we call Configure from lock
dotnet · Apr 28, 2022 · 7654bf2 · 7654bf2
1 parent aef3dc9
commit 7654bf2
Showing 1 changed file with 10 additions and 2 deletions.
diff --git a/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs b/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs
@@ -195,19 +195,27 @@ internal JsonTypeInfo(Type type, JsonConverter converter, JsonSerializerOptions
         }
 
         private bool _isConfigured;
+        private object _configureLock = new object();
 
         internal void EnsureConfigured()
         {
             if (_isConfigured)
                 return;
 
-            Configure();
+            lock (_configureLock)
+            {
+                if (_isConfigured)
+                    return;
+
+                Configure();
 
-            _isConfigured = true;
+                _isConfigured = true;
+            }
         }
 
         internal virtual void Configure()
         {
+            Debug.Assert(Monitor.IsEntered(_configureLock), "Configure called directly, use EnsureConfigured which locks this method");
             JsonConverter converter = PropertyInfoForTypeInfo.ConverterBase;
             Debug.Assert(PropertyInfoForTypeInfo.ConverterStrategy == PropertyInfoForTypeInfo.ConverterBase.ConverterStrategy,
                 $"ConverterStrategy from PropertyInfoForTypeInfo.ConverterStrategy ({PropertyInfoForTypeInfo.ConverterStrategy}) does not match converter's ({PropertyInfoForTypeInfo.ConverterBase.ConverterStrategy})");