This is an automated email from the ASF dual-hosted git repository.
smengcl pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/ozone.git
The following commit(s) were added to refs/heads/master by this push:
new 2ae0ca931e4 HDDS-15341. EC write can fail with
ArrayIndexOutOfBoundsException due to CoderUtil emptyChunk resize race (#10324)
2ae0ca931e4 is described below
commit 2ae0ca931e4dbd7ba0c984b1b719124afd5bd137
Author: Siyao Meng <[email protected]>
AuthorDate: Thu May 28 14:32:07 2026 -0700
HDDS-15341. EC write can fail with ArrayIndexOutOfBoundsException due to
CoderUtil emptyChunk resize race (#10324)
Generated-by: Claude Code (Opus 4.7)
---
.../ozone/erasurecode/rawcoder/CoderUtil.java | 16 +++-
.../ozone/erasurecode/rawcoder/TestCoderUtil.java | 100 +++++++++++++++++++++
2 files changed, 112 insertions(+), 4 deletions(-)
diff --git
a/hadoop-hdds/erasurecode/src/main/java/org/apache/ozone/erasurecode/rawcoder/CoderUtil.java
b/hadoop-hdds/erasurecode/src/main/java/org/apache/ozone/erasurecode/rawcoder/CoderUtil.java
index ebf45e88dda..1fdadcad15b 100644
---
a/hadoop-hdds/erasurecode/src/main/java/org/apache/ozone/erasurecode/rawcoder/CoderUtil.java
+++
b/hadoop-hdds/erasurecode/src/main/java/org/apache/ozone/erasurecode/rawcoder/CoderUtil.java
@@ -38,15 +38,23 @@ private CoderUtil() {
* @return empty chunk of zero bytes
*/
static byte[] getEmptyChunk(int leastLength) {
- if (emptyChunk.length >= leastLength) {
- return emptyChunk; // In most time
+ byte[] chunk = emptyChunk;
+ if (chunk.length >= leastLength) {
+ return chunk; // In most time
}
synchronized (CoderUtil.class) {
- emptyChunk = new byte[leastLength];
+ // Recheck under the lock: another caller may already have grown the
+ // cache while this caller waited. A larger cached chunk is valid for a
+ // smaller request, so only allocate when the cache is still too small.
+ chunk = emptyChunk;
+ if (chunk.length < leastLength) {
+ chunk = new byte[leastLength];
+ emptyChunk = chunk;
+ }
}
- return emptyChunk;
+ return chunk;
}
/**
diff --git
a/hadoop-hdds/erasurecode/src/test/java/org/apache/ozone/erasurecode/rawcoder/TestCoderUtil.java
b/hadoop-hdds/erasurecode/src/test/java/org/apache/ozone/erasurecode/rawcoder/TestCoderUtil.java
new file mode 100644
index 00000000000..2135a31ecc3
--- /dev/null
+++
b/hadoop-hdds/erasurecode/src/test/java/org/apache/ozone/erasurecode/rawcoder/TestCoderUtil.java
@@ -0,0 +1,100 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.ozone.erasurecode.rawcoder;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.fail;
+
+import java.lang.reflect.Field;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests for raw coder utility methods.
+ */
+public class TestCoderUtil {
+
+ private static final int INITIAL_LENGTH = 4096;
+ private static final int SMALL_LENGTH = INITIAL_LENGTH + 1;
+ private static final int LARGE_LENGTH = SMALL_LENGTH * 2;
+
+ @BeforeEach
+ public void resetEmptyChunk() throws Exception {
+ Field emptyChunk = CoderUtil.class.getDeclaredField("emptyChunk");
+ emptyChunk.setAccessible(true);
+ synchronized (CoderUtil.class) {
+ emptyChunk.set(null, new byte[INITIAL_LENGTH]);
+ }
+ }
+
+ @Test
+ // HDDS-15341: This can reproduce the race that can make getEmptyChunk()
+ // return a buffer shorter than requested, which later causes
+ // ArrayIndexOutOfBoundsException when resetBuffer() passes that buffer
+ // to System.arraycopy().
+ public void getEmptyChunkDoesNotShrinkWhenCacheGrowsConcurrently()
+ throws Exception {
+ AtomicReference<Thread> workerThread = new AtomicReference<>();
+ ExecutorService executor = Executors.newSingleThreadExecutor(r -> {
+ Thread thread = new Thread(r, "get-empty-chunk-small");
+ workerThread.set(thread);
+ return thread;
+ });
+
+ try {
+ Future<byte[]> smallChunk;
+ synchronized (CoderUtil.class) {
+ smallChunk = executor.submit(() -> CoderUtil.getEmptyChunk(
+ SMALL_LENGTH));
+ waitUntilBlocked(workerThread);
+ assertThat(CoderUtil.getEmptyChunk(LARGE_LENGTH).length)
+ .isGreaterThanOrEqualTo(LARGE_LENGTH);
+ }
+
+ assertThat(smallChunk.get(10, TimeUnit.SECONDS).length)
+ .as("concurrent caller should return the larger chunk already
cached")
+ .isGreaterThanOrEqualTo(LARGE_LENGTH);
+ assertThat(CoderUtil.getEmptyChunk(LARGE_LENGTH).length)
+ .as("empty chunk cache should not shrink")
+ .isGreaterThanOrEqualTo(LARGE_LENGTH);
+ } finally {
+ executor.shutdownNow();
+ }
+ }
+
+ private static void waitUntilBlocked(AtomicReference<Thread> threadRef)
+ throws InterruptedException {
+ long deadline = System.nanoTime() + TimeUnit.SECONDS.toNanos(10);
+ while (System.nanoTime() < deadline) {
+ Thread thread = threadRef.get();
+ if (thread != null && thread.getState() == Thread.State.BLOCKED) {
+ return;
+ }
+ Thread.sleep(10);
+ }
+
+ Thread thread = threadRef.get();
+ fail("small getEmptyChunk caller did not block on CoderUtil.class; state="
+ + (thread == null ? "not started" : thread.getState()));
+ }
+}
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
