From e42c9e4824358b9b38414df0370919c822ed8523 Mon Sep 17 00:00:00 2001
From: AlanLiu90 <alanliu90@gmail.com>
Date: Mon, 16 May 2022 09:53:06 +0800
Subject: [PATCH] Fixed rare race condition in name table when deserializing on
 device with ARM processors (#2602)

---
 Src/Newtonsoft.Json/DefaultJsonNameTable.cs | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/Src/Newtonsoft.Json/DefaultJsonNameTable.cs b/Src/Newtonsoft.Json/DefaultJsonNameTable.cs
index 5243160e..659eefab 100644
--- a/Src/Newtonsoft.Json/DefaultJsonNameTable.cs
+++ b/Src/Newtonsoft.Json/DefaultJsonNameTable.cs
@@ -24,6 +24,7 @@
 #endregion
 
 using System;
+using System.Threading;
 
 namespace Newtonsoft.Json
 {
@@ -78,7 +79,12 @@ namespace Newtonsoft.Json
             hashCode -= hashCode >> 5;
 
             // make sure index is evaluated before accessing _entries, otherwise potential race condition causing IndexOutOfRangeException
-            var index = hashCode & _mask;
+#if NET20 || NET35 || NET40
+            int mask = Thread.VolatileRead(ref _mask);
+#else
+            int mask = Volatile.Read(ref _mask);
+#endif
+            var index = hashCode & mask;
             var entries = _entries;
 
             for (Entry entry = entries[index]; entry != null; entry = entry.Next)
@@ -160,7 +166,12 @@ namespace Newtonsoft.Json
                 }
             }
             _entries = newEntries;
-            _mask = newMask;
+
+#if NET20 || NET35 || NET40
+            Thread.VolatileWrite(ref _mask, newMask);
+#else
+            Volatile.Write(ref _mask, newMask);
+#endif
         }
 
         private static bool TextEquals(string str1, char[] str2, int str2Start, int str2Length)