[HDFS-11053] Unnecessary superuser check in versionRequest()

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.7.4, 3.0.0-alpha2
• Component/s: namenode, security
• Target Version/s: 2.7.4
• Hadoop Flags: Reviewed
• Assignee: Kihwal Lee
• Reporter: Kihwal Lee
• Created: 25/Oct/16 20:31
• Updated: 27/Oct/16 15:53
• Resolved: 26/Oct/16 14:21

Description

The versionRequest() call does not return any sensitive information. It is mainly used for sanity checks. The presence of checkSuperuserPrivilege() forces users to run datanode as a hdfs superuser.

In secure setup, a keytab obtained from a compromised datanode can allow the intruder to gain hdfs superuser privilege. We should allow datanodes to be run as non-hdfs-superuser by removing checkSuperuserPrivilege() from versionRequest().

Issue Links

• relates to: HDFS-11069 Tighten the authorization of datanode RPC