8190997: PNGImageReader throws NullPointerException when PLTE section is missing
Reviewed-by: serb, bpb, pnarayanan
--- a/src/java.desktop/share/classes/com/sun/imageio/plugins/png/PNGImageReader.java Fri Dec 22 11:00:06 2017 +0530
+++ b/src/java.desktop/share/classes/com/sun/imageio/plugins/png/PNGImageReader.java Tue Dec 26 13:38:31 2017 +0530
@@ -739,6 +739,17 @@
// If chunk type is 'IDAT', we've reached the image data.
if (imageStartPosition == -1L) {
/*
+ * The PNG specification mandates that if colorType is
+ * PNG_COLOR_PALETTE then the PLTE chunk should appear
+ * before the first IDAT chunk.
+ */
+ if (colorType == PNG_COLOR_PALETTE &&
+ !(metadata.PLTE_present))
+ {
+ throw new IIOException("Required PLTE chunk"
+ + " missing");
+ }
+ /*
* PNGs may contain multiple IDAT chunks containing
* a portion of image data. We store the position of
* the first IDAT chunk and continue with iteration
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/javax/imageio/plugins/png/PngPLTEChunkMissingTest.java Tue Dec 26 13:38:31 2017 +0530
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8190997
+ * @summary Test verifies that ImageIO.read() throws proper IIOException
+ * when we have a PNG image with color type PNG_COLOR_PALETTE but
+ * missing the required PLTE chunk.
+ * @run main PngPLTEChunkMissingTest
+ */
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.util.Base64;
+import javax.imageio.IIOException;
+import javax.imageio.ImageIO;
+
+public class PngPLTEChunkMissingTest {
+
+ // PNG image stream missing the required PLTE chunk
+ private static String inputImageBase64 = "iVBORw0KGgoAAAANSUhEUgAAAAEAAAAB"
+ + "CAMAAAA6fptVAAAACklEQVQYV2P4DwABAQEAWk1v8QAAAABJRU5ErkJgggo=";
+
+ public static void main(String[] args) throws Exception {
+
+ byte[] inputBytes = Base64.getDecoder().decode(inputImageBase64);
+ InputStream in = new ByteArrayInputStream(inputBytes);
+
+ /*
+ * Attempt to read a PNG image of color type PNG_COLOR_PALETTE
+ * but missing the required PLTE chunk.
+ */
+ try {
+ ImageIO.read(in);
+ } catch (IIOException e) {
+ /*
+ * We expect ImageIO to throw IIOException with proper message
+ * instead of throwing NullPointerException.
+ */
+ Throwable cause = e.getCause();
+ if (cause == null ||
+ (!(cause.getMessage().
+ equals("Required PLTE chunk missing"))))
+ {
+ throw e;
+ }
+ }
+ }
+}
+