Merge. HDFS-5671. Fix socket leak in DFSInputStream#getBlockReader. Contributed by JamesLi

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1554556 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -438,6 +438,8 @@ Release 2.3.0 - UNRELEASED
     HDFS-5582. hdfs getconf -excludeFile or -includeFile always failed (sathish
     via cmccabe)
 
+    HDFS-5671. Fix socket leak in DFSInputStream#getBlockReader. (JamesLi via umamahesh) 
+
 Release 2.2.0 - 2013-10-13
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java

@@ -1188,11 +1188,21 @@ implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
     }
     // Try to create a new remote peer.
     Peer peer = newTcpPeer(dnAddr);
-    return BlockReaderFactory.newBlockReader(
-        dfsClient.getConf(), file, block, blockToken, startOffset,
-        len, verifyChecksum, clientName, peer, chosenNode, 
-        dsFactory, peerCache, fileInputStreamCache, false,
+    try {
+      reader = BlockReaderFactory.newBlockReader(dfsClient.getConf(), file,
+          block, blockToken, startOffset, len, verifyChecksum, clientName,
+          peer, chosenNode, dsFactory, peerCache, fileInputStreamCache, false,
         curCachingStrategy);
+      return reader;
+    } catch (IOException ex) {
+      DFSClient.LOG.debug(
+          "Exception while getting block reader, closing stale " + peer, ex);
+      throw ex;
+    } finally {
+      if (reader == null) {
+        IOUtils.closeQuietly(peer);
+  }
+    }
   }