From b65e6fcd7f520c763eca0464ebe9515599a73e2c Mon Sep 17 00:00:00 2001
From: Sreeja Chintalapati <schintalapati@Sreejas-MacBook-Pro.local>
Date: Tue, 19 May 2026 10:38:27 +0530
Subject: [PATCH] HDDS-15304. DeleteObjects should enforce the request key
 limit

---
 .../ozone/s3/endpoint/BucketEndpoint.java     |  6 +++
 .../apache/hadoop/ozone/s3/util/S3Consts.java |  3 ++
 .../s3/endpoint/TestObjectMultiDelete.java    | 42 +++++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/endpoint/BucketEndpoint.java b/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/endpoint/BucketEndpoint.java
index 2fd6dee16db7..b65b52e76023 100644
--- a/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/endpoint/BucketEndpoint.java
+++ b/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/endpoint/BucketEndpoint.java
@@ -62,6 +62,7 @@
 import org.apache.hadoop.ozone.s3.exception.OS3Exception;
 import org.apache.hadoop.ozone.s3.exception.S3ErrorTable;
 import org.apache.hadoop.ozone.s3.util.ContinueToken;
+import org.apache.hadoop.ozone.s3.util.S3Consts;
 import org.apache.hadoop.ozone.s3.util.S3Consts.QueryParams;
 import org.apache.hadoop.ozone.s3.util.S3StorageType;
 import org.apache.hadoop.util.Time;
@@ -341,6 +342,11 @@ public MultiDeleteResponse multiDelete(
   ) throws OS3Exception, IOException {
     S3GAction s3GAction = S3GAction.MULTI_DELETE;
 
+    if (request.getObjects() != null
+        && request.getObjects().size() > S3Consts.S3_DELETE_OBJECTS_MAX_KEYS) {
+      throw newError(S3ErrorTable.MALFORMED_XML, bucketName);
+    }
+
     OzoneBucket bucket = getVolume().getBucket(bucketName);
     MultiDeleteResponse result = new MultiDeleteResponse();
     List<String> deleteKeys = new ArrayList<>();
diff --git a/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/util/S3Consts.java b/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/util/S3Consts.java
index 76addc4b9e3d..f0f5e893467d 100644
--- a/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/util/S3Consts.java
+++ b/hadoop-ozone/s3gateway/src/main/java/org/apache/hadoop/ozone/s3/util/S3Consts.java
@@ -95,6 +95,9 @@ public final class S3Consts {
   public static final Pattern TAG_REGEX_PATTERN = Pattern.compile("^([\\p{L}\\p{Z}\\p{N}_.:/=+\\-]*)$");
   public static final String MP_PARTS_COUNT = "x-amz-mp-parts-count";
 
+  /** AWS S3 maximum number of keys per DeleteObjects request. */
+  public static final int S3_DELETE_OBJECTS_MAX_KEYS = 1000;
+
   // Bucket owner condition headers
   // See https://docs.aws.amazon.com/AmazonS3/latest/userguide/bucket-owner-condition.html
   public static final String EXPECTED_BUCKET_OWNER_HEADER = "x-amz-expected-bucket-owner";
diff --git a/hadoop-ozone/s3gateway/src/test/java/org/apache/hadoop/ozone/s3/endpoint/TestObjectMultiDelete.java b/hadoop-ozone/s3gateway/src/test/java/org/apache/hadoop/ozone/s3/endpoint/TestObjectMultiDelete.java
index 8b6c869b5d95..cc687f78c11d 100644
--- a/hadoop-ozone/s3gateway/src/test/java/org/apache/hadoop/ozone/s3/endpoint/TestObjectMultiDelete.java
+++ b/hadoop-ozone/s3gateway/src/test/java/org/apache/hadoop/ozone/s3/endpoint/TestObjectMultiDelete.java
@@ -17,8 +17,10 @@
 
 package org.apache.hadoop.ozone.s3.endpoint;
 
+import static java.net.HttpURLConnection.HTTP_BAD_REQUEST;
 import static java.util.Collections.singleton;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import com.google.common.collect.Sets;
 import java.io.IOException;
@@ -32,6 +34,7 @@
 import org.apache.hadoop.ozone.client.OzoneKey;
 import org.apache.hadoop.ozone.s3.endpoint.MultiDeleteRequest.DeleteObject;
 import org.apache.hadoop.ozone.s3.exception.OS3Exception;
+import org.apache.hadoop.ozone.s3.util.S3Consts;
 import org.junit.jupiter.api.Test;
 
 /**
@@ -101,6 +104,45 @@ public void deleteQuiet() throws IOException, OS3Exception, JAXBException {
     assertEquals(0, response.getErrors().size());
   }
 
+  @Test
+  public void multiDeleteRejectsMoreThanMaxKeysPerRequest() throws Exception {
+    OzoneClient client = new OzoneClientStub();
+    BucketEndpoint rest = EndpointBuilder.newBucketEndpointBuilder()
+        .setClient(client)
+        .build();
+
+    MultiDeleteRequest mdr = new MultiDeleteRequest();
+    for (int i = 0; i < S3Consts.S3_DELETE_OBJECTS_MAX_KEYS + 1; i++) {
+      mdr.getObjects().add(new DeleteObject("key-" + i));
+    }
+
+    OS3Exception ex = assertThrows(OS3Exception.class,
+        () -> rest.multiDelete("b1", "", mdr));
+    assertEquals("MalformedXML", ex.getCode());
+    assertEquals(HTTP_BAD_REQUEST, ex.getHttpCode());
+  }
+
+  @Test
+  public void multiDeleteAllowsMaxKeysPerRequest() throws Exception {
+    OzoneClient client = new OzoneClientStub();
+    OzoneBucket bucket = initTestData(client);
+    BucketEndpoint rest = EndpointBuilder.newBucketEndpointBuilder()
+        .setClient(client)
+        .build();
+
+    MultiDeleteRequest mdr = new MultiDeleteRequest();
+    mdr.setQuiet(true);
+    for (int i = 0; i < S3Consts.S3_DELETE_OBJECTS_MAX_KEYS; i++) {
+      mdr.getObjects().add(new DeleteObject("missing-" + i));
+    }
+
+    MultiDeleteResponse response = rest.multiDelete("b1", "", mdr);
+    assertEquals(0, response.getDeletedObjects().size());
+    assertEquals(0, response.getErrors().size());
+
+    assertEquals(3, Sets.newHashSet(bucket.listKeys("")).size());
+  }
+
   private OzoneBucket initTestData(OzoneClient client) throws IOException {
     client.getObjectStore().createS3Bucket("b1");