From 29bbc79c77708313cedebe4e35689b7468ad870a Mon Sep 17 00:00:00 2001 From: Anupam Yadav Date: Wed, 22 Apr 2026 00:18:25 +0000 Subject: [PATCH] PARQUET-3261: Fix integer overflow in CapacityByteArrayOutputStream The overflow check in addSlab() used bytesUsed which is not updated until after addSlab() returns in write(). This caused the overflow guard to miss cases where bytesAllocated + nextSlabSize exceeds Integer.MAX_VALUE. Fix: - Use bytesAllocated instead of bytesUsed for the overflow check, since bytesAllocated is always up to date when addSlab() is called. - Cap nextSlabSize when it would cause bytesAllocated to overflow, instead of letting Math.addExact throw an uncaught ArithmeticException. --- .../bytes/CapacityByteArrayOutputStream.java | 11 ++- ...CapacityByteArrayOutputStreamOverflow.java | 97 +++++++++++++++++++ 2 files changed, 106 insertions(+), 2 deletions(-) create mode 100644 parquet-common/src/test/java/org/apache/parquet/bytes/TestCapacityByteArrayOutputStreamOverflow.java diff --git a/parquet-common/src/main/java/org/apache/parquet/bytes/CapacityByteArrayOutputStream.java b/parquet-common/src/main/java/org/apache/parquet/bytes/CapacityByteArrayOutputStream.java index 84d3c5b7ba..d3d8b1b6de 100644 --- a/parquet-common/src/main/java/org/apache/parquet/bytes/CapacityByteArrayOutputStream.java +++ b/parquet-common/src/main/java/org/apache/parquet/bytes/CapacityByteArrayOutputStream.java @@ -167,9 +167,10 @@ public CapacityByteArrayOutputStream(int initialSlabSize, int maxCapacityHint, B private void addSlab(int minimumSize) { int nextSlabSize; - // check for overflow + // check for overflow using bytesAllocated which is always up to date (unlike bytesUsed which + // is updated after addSlab returns in write()) try { - Math.addExact(bytesUsed, minimumSize); + Math.addExact(bytesAllocated, minimumSize); } catch (ArithmeticException e) { // This is interpreted as a request for a value greater than Integer.MAX_VALUE // We throw OOM because that is what java.io.ByteArrayOutputStream also does @@ -191,6 +192,12 @@ private void addSlab(int minimumSize) { nextSlabSize = minimumSize; } + // Cap nextSlabSize to avoid integer overflow on bytesAllocated + int maxNextSlabSize = Integer.MAX_VALUE - bytesAllocated; + if (nextSlabSize > maxNextSlabSize) { + nextSlabSize = max(minimumSize, maxNextSlabSize); + } + LOG.debug("used {} slabs, adding new slab of size {}", slabs.size(), nextSlabSize); this.currentSlab = allocator.allocate(nextSlabSize); diff --git a/parquet-common/src/test/java/org/apache/parquet/bytes/TestCapacityByteArrayOutputStreamOverflow.java b/parquet-common/src/test/java/org/apache/parquet/bytes/TestCapacityByteArrayOutputStreamOverflow.java new file mode 100644 index 0000000000..771d9e17b4 --- /dev/null +++ b/parquet-common/src/test/java/org/apache/parquet/bytes/TestCapacityByteArrayOutputStreamOverflow.java @@ -0,0 +1,97 @@ +/* + * 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.parquet.bytes; + +import static org.junit.Assert.assertEquals; +import static org.junit.Assert.assertThrows; + +import java.lang.reflect.Field; +import org.junit.After; +import org.junit.Before; +import org.junit.Test; + +/** + * Tests for integer overflow handling in {@link CapacityByteArrayOutputStream#addSlab(int)}. + * Verifies the fix for PARQUET-3261. + */ +public class TestCapacityByteArrayOutputStreamOverflow { + + private TrackingByteBufferAllocator allocator; + + @Before + public void initAllocator() { + allocator = TrackingByteBufferAllocator.wrap(new HeapByteBufferAllocator()); + } + + @After + public void closeAllocator() { + allocator.close(); + } + + /** + * Regression test for PARQUET-3261: bytesAllocated overflow in addSlab(). + * Simulates near-overflow by setting bytesAllocated via reflection, then verifying + * that addSlab caps the slab size instead of throwing ArithmeticException. + */ + @Test + public void testAddSlabCapsSlabSizeNearIntegerMaxValue() throws Exception { + int slabSize = 1024; + try (CapacityByteArrayOutputStream cbaos = + new CapacityByteArrayOutputStream(slabSize, Integer.MAX_VALUE, allocator)) { + // Write initial data to set up internal state + byte[] data = new byte[slabSize]; + cbaos.write(data, 0, data.length); + + // Simulate near-overflow by setting bytesAllocated close to Integer.MAX_VALUE + Field bytesAllocatedField = CapacityByteArrayOutputStream.class.getDeclaredField("bytesAllocated"); + bytesAllocatedField.setAccessible(true); + bytesAllocatedField.setInt(cbaos, Integer.MAX_VALUE - 100); + + // Writing 1 byte triggers addSlab with minimumSize=1. + // Without the fix, the doubling strategy would compute nextSlabSize = bytesUsed (1024), + // and bytesAllocated + 1024 would overflow. With the fix, nextSlabSize is capped to 100. + cbaos.write(1); + assertEquals(slabSize + 1, cbaos.size()); + } + } + + /** + * Verify that a true overflow (bytesAllocated + minimumSize > Integer.MAX_VALUE) + * still throws OutOfMemoryError. + */ + @Test + public void testAddSlabThrowsOOMOnTrueOverflow() throws Exception { + int slabSize = 1024; + try (CapacityByteArrayOutputStream cbaos = + new CapacityByteArrayOutputStream(slabSize, Integer.MAX_VALUE, allocator)) { + byte[] data = new byte[slabSize]; + cbaos.write(data, 0, data.length); + + // Set bytesAllocated so that even minimumSize=200 would overflow + Field bytesAllocatedField = CapacityByteArrayOutputStream.class.getDeclaredField("bytesAllocated"); + bytesAllocatedField.setAccessible(true); + bytesAllocatedField.setInt(cbaos, Integer.MAX_VALUE - 50); + + // Writing 200 bytes requires minimumSize=200, but only 50 bytes remain. + // The addExact(bytesAllocated, minimumSize) check should throw OOM. + byte[] tooLarge = new byte[200]; + assertThrows(OutOfMemoryError.class, () -> cbaos.write(tooLarge, 0, tooLarge.length)); + } + } +}