From 5a201d633fd90a14ba76795683be36b05baedff0 Mon Sep 17 00:00:00 2001
From: 1fanwang <1fannnw@gmail.com>
Date: Tue, 25 Aug 2026 02:50:59 -0400
Subject: [PATCH] ZOOKEEPER-4947: Close clients after authentication failure

ZooKeeper.close() treated AUTH_FAILED clients as already closed and skipped prompt shutdown of their connection threads.

Signed-off-by: 1fanwang <1fannnw@gmail.com>
---
 .../src/main/java/org/apache/zookeeper/ZooKeeper.java  |  2 +-
 .../org/apache/zookeeper/test/SaslAuthFailTest.java    | 10 ++++++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/zookeeper-server/src/main/java/org/apache/zookeeper/ZooKeeper.java b/zookeeper-server/src/main/java/org/apache/zookeeper/ZooKeeper.java
index 239f97b0f70..20e8e2cddd2 100644
--- a/zookeeper-server/src/main/java/org/apache/zookeeper/ZooKeeper.java
+++ b/zookeeper-server/src/main/java/org/apache/zookeeper/ZooKeeper.java
@@ -1319,7 +1319,7 @@ public synchronized void register(Watcher watcher) {
      * @throws InterruptedException
      */
     public synchronized void close() throws InterruptedException {
-        if (!cnxn.getState().isAlive()) {
+        if (cnxn.getState() == States.CLOSED) {
             LOG.debug("Close called on already closed client");
             return;
         }
diff --git a/zookeeper-server/src/test/java/org/apache/zookeeper/test/SaslAuthFailTest.java b/zookeeper-server/src/test/java/org/apache/zookeeper/test/SaslAuthFailTest.java
index 2384cd612ef..3f586c247d3 100644
--- a/zookeeper-server/src/test/java/org/apache/zookeeper/test/SaslAuthFailTest.java
+++ b/zookeeper-server/src/test/java/org/apache/zookeeper/test/SaslAuthFailTest.java
@@ -18,11 +18,14 @@
 
 package org.apache.zookeeper.test;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assertions.fail;
 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 import org.apache.zookeeper.CreateMode;
 import org.apache.zookeeper.WatchedEvent;
 import org.apache.zookeeper.Watcher.Event.KeeperState;
@@ -88,9 +91,12 @@ public void testAuthFail() {
 
     @Test
     public void testBadSaslAuthNotifiesWatch() throws Exception {
-        try (ZooKeeper ignored = createClient(new MyWatcher(), hostPort)) {
+        try (ZooKeeper zk = createClient(new MyWatcher(), hostPort)) {
             // wait for authFailed event from client's EventThread.
-            authFailed.await();
+            assertTrue(authFailed.await(CONNECTION_TIMEOUT, TimeUnit.MILLISECONDS));
+            zk.close();
+            assertEquals(ZooKeeper.States.CLOSED, zk.getState());
+            assertTrue(zk.close(CONNECTION_TIMEOUT));
         }
     }