[HADOOP-1195] NullPointerException in FSNamesystem due to getDatanode() return value is not checked

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.16.0
• Assignee: Dhruba Borthakur
• Reporter: Konstantin Shvachko
• Created: 03/Apr/07 00:44
• Updated: 08/Jul/09 16:42
• Resolved: 25/Jan/08 09:20

Description

FSNamesystem.getDatanode( nodeID ) returns null if the node is not found.
There are several places where we do not check wether the returned node is null, e.g.
FSNamesystem.processReport()
FSNamesystem.setDatanodeDead()
FSNamesystem.invalidateBlock()
FSNamesystem.verifyNodeRegistration()

I'm getting the following NPE:

07/04/02 17:31:50 WARN dfs.DataNode: org.apache.hadoop.ipc.RemoteException: java.io.IOException: java.lang.NullPointerException
at org.apache.hadoop.dfs.FSNamesystem.shouldNodeShutdown(FSNamesystem.java:3306)
at org.apache.hadoop.dfs.FSNamesystem.processReport(FSNamesystem.java:2012)
at org.apache.hadoop.dfs.NameNode.blockReport(NameNode.java:654)
at sun.reflect.GeneratedMethodAccessor7.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:341)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:580)

at org.apache.hadoop.ipc.Client.call(Client.java:473)
at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:164)
at org.apache.hadoop.dfs.$Proxy1.blockReport(Unknown Source)
at org.apache.hadoop.dfs.DataNode.offerService(DataNode.java:460)
at org.apache.hadoop.dfs.DataNode.run(DataNode.java:1095)
at org.apache.hadoop.dfs.MiniDFSCluster$DataNodeRunner.run(MiniDFSCluster.java:160)
at java.lang.Thread.run(Thread.java:595)