Fix for reflog corruption caused by multiline message

If a client passes a multiline message as argument to ReflogWriter.log()
the Reflog gets corrupted and cannot be parsed. ReflogWriter.log() is
invoked implicitly from various commands such as StashCreate, Rebase and
many more. However the message is not always filtered for line feeds.

Such an example is the StashCreateOperation of EGit which passes
unchecked user input as commit message. If a multiline comment is pasted
to the stash create dialog, the reflog gets corrupted.

ReflogWriter now replaces line endings in log message with spaces.

Bug: 435509
Change-Id: I3010cc902e13bee4d7b6696dfd11ab51062739d3
Signed-off-by: Andreas Hermann <a.v.hermann@gmail.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/ReflogWriterTest.java

@@ -0,0 +1,96 @@
+/*******************************************************************************
+ * Copyright (c) 2014 Andreas Hermann
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *******************************************************************************/
+package org.eclipse.jgit.internal.storage.file;
+
+import static org.junit.Assert.assertEquals;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.PersonIdent;
+import org.eclipse.jgit.test.resources.SampleDataRepositoryTestCase;
+import org.junit.Test;
+
+public class ReflogWriterTest extends SampleDataRepositoryTestCase {
+
+	private static String oneLine = "da85355dfc525c9f6f3927b876f379f46ccf826e 3e7549db262d1e836d9bf0af7e22355468f1717c"
+			+ " John Doe <john@doe.com> 1243028200 +0200\tstash: Add message with line feeds\n";
+
+	@Test
+	public void shouldFilterLineFeedFromMessage() throws Exception {
+		ReflogWriter writer = new ReflogWriter(db);
+		PersonIdent ident = new PersonIdent("John Doe", "john@doe.com",
+				1243028200000L, 120);
+		ObjectId oldId = ObjectId
+				.fromString("da85355dfc525c9f6f3927b876f379f46ccf826e");
+		ObjectId newId = ObjectId
+				.fromString("3e7549db262d1e836d9bf0af7e22355468f1717c");
+
+		writer.log("refs/heads/master", oldId, newId, ident,
+				"stash: Add\nmessage\r\nwith line feeds");
+
+		byte[] buffer = new byte[oneLine.getBytes().length];
+		readReflog(buffer);
+		assertEquals(oneLine, new String(buffer));
+	}
+
+	private void readReflog(byte[] buffer)
+			throws FileNotFoundException, IOException {
+		File logfile = new File(db.getDirectory(), "logs/refs/heads/master");
+		if (!logfile.getParentFile().mkdirs()
+				&& !logfile.getParentFile().isDirectory()) {
+			throw new IOException(
+					"oops, cannot create the directory for the test reflog file"
+							+ logfile);
+		}
+		FileInputStream fileInputStream = new FileInputStream(logfile);
+		try {
+			fileInputStream.read(buffer);
+		} finally {
+			fileInputStream.close();
+		}
+	}
+}

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ReflogWriter.java

@@ -237,7 +237,7 @@ public class ReflogWriter {
 		r.append(' ');
 		r.append(ident.toExternalString());
 		r.append('\t');
-		r.append(message);
+		r.append(message.replace("\r\n", " ").replace("\n", " ")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$
 		r.append('\n');
 		return Constants.encode(r.toString());
 	}