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https://issues.apache.org/jira/browse/HDFS-6165?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13970052#comment-13970052
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Daryn Sharp commented on HDFS-6165:
-----------------------------------

After looking over the FsShell code, I'll revise my stance.  I think the only 
change, for now, is the NN should only check permissions of the parent 
directory for deletes.  The permissions of the file/dir shouldn't matter.  
FsShell isn't recursively descending like I thought...  (Explains why deletion 
of a dir with millions of files took down a NN)

While it's technically wrong and violates posix to allow deleting a non-empty 
directory to which the user has no permissions, it doesn't make anything worse. 
 The NN's recursive delete is already terribly broken in that it ignores 
permissions deeper in the tree.

I bet for the described problem, you could delete the no-perms dir if you 
created a new directory, moved the no-perms dir into it, and then recursively 
deleted the new directory.

> "hdfs dfs -rm -r" and "hdfs -rmdir" commands can't remove empty directory 
> --------------------------------------------------------------------------
>
>                 Key: HDFS-6165
>                 URL: https://issues.apache.org/jira/browse/HDFS-6165
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: hdfs-client
>    Affects Versions: 2.3.0
>            Reporter: Yongjun Zhang
>            Assignee: Yongjun Zhang
>            Priority: Minor
>         Attachments: HDFS-6165.001.patch, HDFS-6165.002.patch, 
> HDFS-6165.003.patch, HDFS-6165.004.patch, HDFS-6165.004.patch
>
>
> Given a directory owned by user A with WRITE permission containing an empty 
> directory owned by user B, it is not possible to delete user B's empty 
> directory with either "hdfs dfs -rm -r" or "hdfs dfs -rmdir". Because the 
> current implementation requires FULL permission of the empty directory, and 
> throws exception. 
> On the other hand, on linux, "rm -r" and "rmdir" command can remove empty 
> directory as long as the parent directory has WRITE permission (and prefix 
> component of the path have EXECUTE permission), For the tested OSes, some 
> prompt user asking for confirmation, some don't.
> Here's a reproduction:
> {code}
> [root@vm01 ~]# hdfs dfs -ls /user/
> Found 4 items
> drwxr-xr-x   - userabc users               0 2013-05-03 01:55 /user/userabc
> drwxr-xr-x   - hdfs    supergroup          0 2013-05-03 00:28 /user/hdfs
> drwxrwxrwx   - mapred  hadoop              0 2013-05-03 00:13 /user/history
> drwxr-xr-x   - hdfs    supergroup          0 2013-04-14 16:46 /user/hive
> [root@vm01 ~]# hdfs dfs -ls /user/userabc
> Found 8 items
> drwx------   - userabc users          0 2013-05-02 17:00 /user/userabc/.Trash
> drwxr-xr-x   - userabc users          0 2013-05-03 01:34 /user/userabc/.cm
> drwx------   - userabc users          0 2013-05-03 01:06 
> /user/userabc/.staging
> drwxr-xr-x   - userabc users          0 2013-04-14 18:31 /user/userabc/apps
> drwxr-xr-x   - userabc users          0 2013-04-30 18:05 /user/userabc/ds
> drwxr-xr-x   - hdfs    users          0 2013-05-03 01:54 /user/userabc/foo
> drwxr-xr-x   - userabc users          0 2013-04-30 16:18 
> /user/userabc/maven_source
> drwxr-xr-x   - hdfs    users          0 2013-05-03 01:40 
> /user/userabc/test-restore
> [root@vm01 ~]# hdfs dfs -ls /user/userabc/foo/
> [root@vm01 ~]# sudo -u userabc hdfs dfs -rm -r -skipTrash /user/userabc/foo
> rm: Permission denied: user=userabc, access=ALL, 
> inode="/user/userabc/foo":hdfs:users:drwxr-xr-x
> {code}
> The super user can delete the directory.
> {code}
> [root@vm01 ~]# sudo -u hdfs hdfs dfs -rm -r -skipTrash /user/userabc/foo
> Deleted /user/userabc/foo
> {code}
> The same is not true for files, however. They have the correct behavior.
> {code}
> [root@vm01 ~]# sudo -u hdfs hdfs dfs -touchz /user/userabc/foo-file
> [root@vm01 ~]# hdfs dfs -ls /user/userabc/
> Found 8 items
> drwx------   - userabc users          0 2013-05-02 17:00 /user/userabc/.Trash
> drwxr-xr-x   - userabc users          0 2013-05-03 01:34 /user/userabc/.cm
> drwx------   - userabc users          0 2013-05-03 01:06 
> /user/userabc/.staging
> drwxr-xr-x   - userabc users          0 2013-04-14 18:31 /user/userabc/apps
> drwxr-xr-x   - userabc users          0 2013-04-30 18:05 /user/userabc/ds
> -rw-r--r--   1 hdfs    users          0 2013-05-03 02:11 
> /user/userabc/foo-file
> drwxr-xr-x   - userabc users          0 2013-04-30 16:18 
> /user/userabc/maven_source
> drwxr-xr-x   - hdfs    users          0 2013-05-03 01:40 
> /user/userabc/test-restore
> [root@vm01 ~]# sudo -u userabc hdfs dfs -rm -skipTrash /user/userabc/foo-file
> Deleted /user/userabc/foo-file
> {code}
> Using "hdfs dfs -rmdir" command:
> {code}
> bash-4.1$ hadoop fs -lsr /
> lsr: DEPRECATED: Please use 'ls -R' instead.
> drwxr-xr-x   - hdfs supergroup          0 2014-03-25 16:29 /user
> drwxr-xr-x   - hdfs   supergroup          0 2014-03-25 16:28 /user/hdfs
> drwxr-xr-x   - usrabc users               0 2014-03-28 23:39 /user/usrabc
> drwxr-xr-x   - abc    abc                 0 2014-03-28 23:39 
> /user/usrabc/foo-empty1
> [root@vm01 usrabc]# su usrabc
> [usrabc@vm01 ~]$ hdfs dfs -rmdir /user/usrabc/foo-empty1
> rmdir: Permission denied: user=usrabc, access=ALL, 
> inode="/user/usrabc/foo-empty1":abc:abc:drwxr-xr-x
> {code}



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