From 6b3b2b33a528458aa23428db7d43655aa0d883d5 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Mon, 8 May 2023 13:55:40 -0700 Subject: [PATCH] GraphObjectIndex: fix search in findGraphPosition In findGraphPosition, when there is no object whose OID starts with the first byte of the sought OID, low equals high. This violates an invariant of the loop, and when the sought OID is lexicographically greater than every other OID in the repository, causes an ArrayIndexOutOfBoundsException (because we're trying to read outside the list of OIDs). Therefore, check the "low < high" condition at the start of the loop, not only after the first iteration. Change-Id: Ic8ac198c151bd161c4996b9e7cb6e6660f151733 Helped-by: Ivan Frade Signed-off-by: Jonathan Tan --- .../commitgraph/GraphObjectIndexTest.java | 28 +++++++++++++++++++ .../storage/commitgraph/GraphObjectIndex.java | 4 +-- 2 files changed, 30 insertions(+), 2 deletions(-) create mode 100644 org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndexTest.java diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndexTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndexTest.java new file mode 100644 index 000000000..b533d5c98 --- /dev/null +++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndexTest.java @@ -0,0 +1,28 @@ +/* + * Copyright (C) 2023, Google LLC + * + * This program and the accompanying materials are made available under the + * terms of the Eclipse Distribution License v. 1.0 which is available at + * https://www.eclipse.org/org/documents/edl-v10.php. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +package org.eclipse.jgit.internal.storage.commitgraph; + +import org.eclipse.jgit.lib.ObjectId; +import org.junit.Test; +import static org.junit.Assert.assertEquals; + +public class GraphObjectIndexTest { + + @Test + public void findGraphPosition_noObjInBucket() throws CommitGraphFormatException { + GraphObjectIndex idx = new GraphObjectIndex(100, + new byte[256 * 4], new byte[] {}); + int graphPosition = idx.findGraphPosition( + ObjectId.fromString("731dfd4c5eb6f88b98e983b9b0551b3562a0c46c")); + assertEquals(-1, graphPosition); + } + +} diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndex.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndex.java index b0df46732..22b4011f9 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndex.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/commitgraph/GraphObjectIndex.java @@ -80,7 +80,7 @@ int findGraphPosition(AnyObjectId id) { if (levelOne > 0) { low = fanoutTable[levelOne - 1]; } - do { + while (low < high) { int mid = (low + high) >>> 1; int pos = objIdOffset(mid); int cmp = id.compareTo(oidLookup, pos); @@ -91,7 +91,7 @@ int findGraphPosition(AnyObjectId id) { } else { low = mid + 1; } - } while (low < high); + } return -1; }