[HDFS-12485] expunge may fail to remove trash from encryption zone

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.8.0, 3.0.0-alpha1
• Fix Version/s: 2.9.0, 2.8.3, 3.0.0
• Hadoop Flags: Reviewed
• Assignee: Wei-Chiu Chuang
• Reporter: Wei-Chiu Chuang
• Created: 18/Sep/17 22:42
• Updated: 02/Oct/19 17:15
• Resolved: 16/Oct/17 20:09

Description

This is related to HDFS-12484, but turns out that even if I have super user permission, -expunge may not remove trash either.

If I log into Linux as root, and then login as the superuser [e-mail]

[root@nightly511-1 ~]# hdfs dfs -rm /scale/b
17/09/18 15:21:32 INFO fs.TrashPolicyDefault: Moved: 'hdfs://ns1/scale/b' to trash at: hdfs://ns1/scale/.Trash/hdfs/Current/scale/b
[root@nightly511-1 ~]# hdfs dfs -expunge
17/09/18 15:21:59 INFO fs.TrashPolicyDefault: TrashPolicyDefault#deleteCheckpoint for trashRoot: hdfs://ns1/user/hdfs/.Trash
17/09/18 15:21:59 INFO fs.TrashPolicyDefault: TrashPolicyDefault#deleteCheckpoint for trashRoot: hdfs://ns1/user/hdfs/.Trash
17/09/18 15:21:59 INFO fs.TrashPolicyDefault: Deleted trash checkpoint: /user/hdfs/.Trash/170918143916
17/09/18 15:21:59 INFO fs.TrashPolicyDefault: TrashPolicyDefault#createCheckpoint for trashRoot: hdfs://ns1/user/hdfs/.Trash
[root@nightly511-1 ~]# hdfs dfs -ls hdfs://ns1/scale/.Trash/hdfs/Current/scale/b
-rw-r--r--   3 hdfs systest          0 2017-09-18 15:21 hdfs://ns1/scale/.Trash/hdfs/Current/scale/b

expunge does not remove trash under /scale, because it does not know I am 'hdfs' user.

DistributedFileSystem#getTrashRoots

Path ezTrashRoot = new Path(it.next().getPath(),
            FileSystem.TRASH_PREFIX);
        if (!exists(ezTrashRoot)) {
          continue;
        }
        if (allUsers) {
          for (FileStatus candidate : listStatus(ezTrashRoot)) {
            if (exists(candidate.getPath())) {
              ret.add(candidate);
            }
          }
        } else {
          Path userTrash = new Path(ezTrashRoot, System.getProperty(
              "user.name")); --> bug
          try {
            ret.add(getFileStatus(userTrash));
          } catch (FileNotFoundException ignored) {
          }
        }

It should use UGI for user name, rather than system login user name.