guard base256 length read in datamatrix decodeBase256Segment (#2084)

1 files changed, 9 insertions, 0 deletions

diff --git a/core/src/test/java/com/google/zxing/datamatrix/decoder/DecodedBitStreamParserTestCase.java b/core/src/test/java/com/google/zxing/datamatrix/decoder/DecodedBitStreamParserTestCase.java
index a0bbc58d3..af44989d2 100644
--- a/core/src/test/java/com/google/zxing/datamatrix/decoder/DecodedBitStreamParserTestCase.java
+++ b/core/src/test/java/com/google/zxing/datamatrix/decoder/DecodedBitStreamParserTestCase.java
@@ -16,6 +16,7 @@
 
 package com.google.zxing.datamatrix.decoder;
 
+import com.google.zxing.FormatException;
 import org.junit.Assert;
 import org.junit.Test;
 
@@ -42,6 +43,14 @@ public final class DecodedBitStreamParserTestCase extends Assert {
     assertEquals("00019899", decodedString);
   }
   
+  @Test(expected = FormatException.class)
+  public void testBase256TruncatedLongLength() throws Exception {
+    // 231 latches to Base 256. The next byte unrandomizes to 250 at codeword position 2,
+    // which signals a multi-byte length, but no further byte is present to read.
+    byte[] bytes = {(byte) 231, (byte) 38};
+    DecodedBitStreamParser.decode(bytes);
+  }
+
   // TODO(bbrown): Add test cases for each encoding type
   // TODO(bbrown): Add test cases for switching encoding types
 }
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