[HDFS-7382] DataNode in secure mode may throw NullPointerException if client connects before DataNode registers itself with NameNode.

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.6.0
• Component/s: datanode, security
• Target Version/s: 2.6.0
• Hadoop Flags: Reviewed
• Assignee: Chris Nauroth
• Reporter: Chris Nauroth
• Created: 08/Nov/14 22:19
• Updated: 01/Dec/14 03:08
• Resolved: 09/Nov/14 06:34

Description

SaslDataTransferServer#receive needs to check if the DataNode is listening on a privileged port. It does this by checking the address from the DatanodeID. However, there is a window of time when this will be null. If a client is still holding a LocatedBlock that references that DataNode and chooses to connect, then there is a risk of getting a NullPointerException.

Issue Links

• is broken by: HDFS-2856 Fix block protocol so that Datanodes don't require root or jsvc
• relates to: HDFS-7386 Replace check "port number < 1024" with shared isPrivilegedPort method