From f140506d6756f8d9aaeb728e5309ab27c513f996 Mon Sep 17 00:00:00 2001
From: FuzzingTeam <114765570+FuzzingTeam@users.noreply.github.com>
Date: Tue, 25 Oct 2022 22:37:49 +0530
Subject: [PATCH] HADOOP-18504. Fixed an unhandled NullPointerException in
 class KeyProvider (#5064)

Contributed by FuzzingTeam
---
 .../main/java/org/apache/hadoop/crypto/key/KeyProvider.java    | 3 ++-
 .../java/org/apache/hadoop/crypto/key/TestKeyProvider.java     | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/key/KeyProvider.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/key/KeyProvider.java
index 4d1674bd7b8..5e207251805 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/key/KeyProvider.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/key/KeyProvider.java
@@ -639,13 +639,14 @@ public abstract class KeyProvider implements Closeable {
   public abstract void flush() throws IOException;
 
   /**
-   * Split the versionName in to a base name. Converts "/aaa/bbb/3" to
+   * Split the versionName in to a base name. Converts "/aaa/bbb@3" to
    * "/aaa/bbb".
    * @param versionName the version name to split
    * @return the base name of the key
    * @throws IOException raised on errors performing I/O.
    */
   public static String getBaseName(String versionName) throws IOException {
+    Objects.requireNonNull(versionName, "VersionName cannot be null");
     int div = versionName.lastIndexOf('@');
     if (div == -1) {
       throw new IOException("No version in key path " + versionName);
diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/crypto/key/TestKeyProvider.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/crypto/key/TestKeyProvider.java
index cb6a1fb31e6..b0c3b090022 100644
--- a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/crypto/key/TestKeyProvider.java
+++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/crypto/key/TestKeyProvider.java
@@ -36,6 +36,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.hadoop.test.LambdaTestUtils.intercept;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
@@ -62,6 +63,8 @@ public class TestKeyProvider {
     } catch (IOException e) {
       assertTrue(true);
     }
+    intercept(NullPointerException.class, () ->
+        KeyProvider.getBaseName(null));
   }
 
   @Test