Merge "GZIPInputStream: Correctly handle extras in gzip headers."

2 files changed, 17 insertions, 1 deletions

diff --git a/luni/src/main/java/java/util/zip/GZIPInputStream.java b/luni/src/main/java/java/util/zip/GZIPInputStream.java
index afbbafe..925e8c4 100644
--- a/luni/src/main/java/java/util/zip/GZIPInputStream.java
+++ b/luni/src/main/java/java/util/zip/GZIPInputStream.java
@@ -222,7 +222,7 @@ public class GZIPInputStream extends InflaterInputStream {
             if (hcrc) {
                 crc.update(header, 0, 2);
             }
-            int length = Memory.peekShort(scratch, 0, ByteOrder.LITTLE_ENDIAN) & 0xffff;
+            int length = Memory.peekShort(header, 0, ByteOrder.LITTLE_ENDIAN) & 0xffff;
             while (length > 0) {
                 int max = length > scratch.length ? scratch.length : length;
                 int result = in.read(scratch, 0, max);
diff --git a/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java b/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java
index 153f324..5813753 100644
--- a/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java
+++ b/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java
@@ -51,6 +51,18 @@ public final class GZIPInputStreamTest extends TestCase {
         -13, 72, -51, -55, -55, 87, 8, -49, 47, -54, 73, 1, 0, 86, -79, 23, 74, 11, 0, 0, 0  // data
     };
 
+    /*(
+     * This is the same as {@code HELLO_WORLD_GZIPPED} except that the 4th header byte is 4
+     * (FEXTRA flag) and that the 8 bytes after the header make up the extra.
+     *
+     * Constructed manually because none of the commonly used tools appear to emit header CRCs.
+     */
+    private static final byte[] HELLO_WORLD_GZIPPED_WITH_EXTRA = new byte[] {
+        31, -117, 8, 4, 0, 0, 0, 0, 0, 0,  // 10 byte header
+        6, 0, 4, 2, 4, 2, 4, 2,  // 2 byte extra length + 6 byte extra.
+        -13, 72, -51, -55, -55, 87, 8, -49, 47, -54, 73, 1, 0, 86, -79, 23, 74, 11, 0, 0, 0  // data
+    };
+
     public void testShortMessage() throws IOException {
         assertEquals("Hello World", new String(gunzip(HELLO_WORLD_GZIPPED), "UTF-8"));
     }
@@ -59,6 +71,10 @@ public final class GZIPInputStreamTest extends TestCase {
         assertEquals("Hello World", new String(gunzip(HELLO_WORLD_GZIPPED_WITH_HEADER_CRC), "UTF-8"));
     }
 
+    public void testShortMessageWithHeaderExtra() throws IOException {
+        assertEquals("Hello World", new String(gunzip(HELLO_WORLD_GZIPPED_WITH_EXTRA), "UTF-8"));
+    }
+
     public void testLongMessage() throws IOException {
         byte[] data = new byte[1024 * 1024];
         new Random().nextBytes(data);