From 79e157a32ec9f4ffaa8373658d289167b9d8e2a1 Mon Sep 17 00:00:00 2001
From: brido4125 <hcs4125@gmail.com>
Date: Tue, 2 Jul 2024 09:54:46 +0900
Subject: [PATCH] FIX: Concurrency problem in locator allNodes.

---
 .../java/net/spy/memcached/ArcusKetamaNodeLocator.java    | 8 +++++---
 .../net/spy/memcached/ArcusReplKetamaNodeLocator.java     | 8 +++++---
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/main/java/net/spy/memcached/ArcusKetamaNodeLocator.java b/src/main/java/net/spy/memcached/ArcusKetamaNodeLocator.java
index 66aa7be4b..70246ad76 100644
--- a/src/main/java/net/spy/memcached/ArcusKetamaNodeLocator.java
+++ b/src/main/java/net/spy/memcached/ArcusKetamaNodeLocator.java
@@ -41,7 +41,7 @@
 public class ArcusKetamaNodeLocator extends SpyObject implements NodeLocator {
 
   private final TreeMap<Long, SortedSet<MemcachedNode>> ketamaNodes;
-  private final Collection<MemcachedNode> allNodes;
+  private Collection<MemcachedNode> allNodes;
 
   /* ENABLE_MIGRATION if */
   private TreeMap<Long, SortedSet<MemcachedNode>> ketamaAlterNodes;
@@ -206,15 +206,16 @@ public void update(Collection<MemcachedNode> toAttach,
                      Collection<MemcachedNode> toDelete) {
     lock.lock();
     try {
+      ArrayList<MemcachedNode> newAllNodes = new ArrayList<>(allNodes);
       // Add memcached nodes.
       for (MemcachedNode node : toAttach) {
-        allNodes.add(node);
+        newAllNodes.add(node);
         insertHash(node);
       }
 
       // Remove memcached nodes.
       for (MemcachedNode node : toDelete) {
-        allNodes.remove(node);
+        newAllNodes.remove(node);
         removeHash(node);
         try {
           node.closeChannel();
@@ -223,6 +224,7 @@ public void update(Collection<MemcachedNode> toAttach,
                   "Failed to closeChannel the node : " + node);
         }
       }
+      allNodes = newAllNodes;
     } finally {
       /* ENABLE_MIGRATION if */
       if (migrationInProgress && alterNodes.isEmpty()) {
diff --git a/src/main/java/net/spy/memcached/ArcusReplKetamaNodeLocator.java b/src/main/java/net/spy/memcached/ArcusReplKetamaNodeLocator.java
index a01259aca..55a721dbc 100644
--- a/src/main/java/net/spy/memcached/ArcusReplKetamaNodeLocator.java
+++ b/src/main/java/net/spy/memcached/ArcusReplKetamaNodeLocator.java
@@ -42,7 +42,7 @@ public class ArcusReplKetamaNodeLocator extends SpyObject implements NodeLocator
 
   private final TreeMap<Long, SortedSet<MemcachedReplicaGroup>> ketamaGroups;
   private final HashMap<String, MemcachedReplicaGroup> allGroups;
-  private final Collection<MemcachedNode> allNodes;
+  private Collection<MemcachedNode> allNodes;
 
   /* ENABLE_MIGRATION if */
   private TreeMap<Long, SortedSet<MemcachedReplicaGroup>> ketamaAlterGroups;
@@ -251,9 +251,10 @@ public void update(Collection<MemcachedNode> toAttach,
      */
     lock.lock();
     try {
+      ArrayList<MemcachedNode> newAllNodes = new ArrayList<>(allNodes);
       // Remove memcached nodes.
       for (MemcachedNode node : toDelete) {
-        allNodes.remove(node);
+        newAllNodes.remove(node);
         removeNodeFromGroup(node);
         try {
           node.closeChannel();
@@ -269,7 +270,7 @@ public void update(Collection<MemcachedNode> toAttach,
 
       // Add memcached nodes.
       for (MemcachedNode node : toAttach) {
-        allNodes.add(node);
+        newAllNodes.add(node);
         insertNodeIntoGroup(node);
       }
 
@@ -280,6 +281,7 @@ public void update(Collection<MemcachedNode> toAttach,
         removeHash(group);
       }
       toDeleteGroups.clear();
+      allNodes = newAllNodes;
     } finally {
       /* ENABLE_MIGRATION if */
       if (migrationInProgress && alterNodes.isEmpty()) {