[SPARK-12084][CORE] Fix codes that uses ByteBuffer.array incorrectly

`ByteBuffer` doesn't guarantee all contents in `ByteBuffer.array` are valid. E.g, a ByteBuffer returned by `ByteBuffer.slice`. We should not use the whole content of `ByteBuffer` unless we know that's correct.

This patch fixed all places that use `ByteBuffer.array` incorrectly.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #10083 from zsxwing/bytebuffer-array.

1 files changed, 4 insertions, 1 deletions

diff --git a/examples/src/main/scala/org/apache/spark/examples/pythonconverters/AvroConverters.scala b/examples/src/main/scala/org/apache/spark/examples/pythonconverters/AvroConverters.scala
index 805184e740..cf12c98b4a 100644
--- a/examples/src/main/scala/org/apache/spark/examples/pythonconverters/AvroConverters.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/pythonconverters/AvroConverters.scala
@@ -79,7 +79,10 @@ object AvroConversionUtil extends Serializable {
 
   def unpackBytes(obj: Any): Array[Byte] = {
     val bytes: Array[Byte] = obj match {
-      case buf: java.nio.ByteBuffer => buf.array()
+      case buf: java.nio.ByteBuffer =>
+        val arr = new Array[Byte](buf.remaining())
+        buf.get(arr)
+        arr
       case arr: Array[Byte] => arr
       case other => throw new SparkException(
         s"Unknown BYTES type ${other.getClass.getName}")