OES FTP session hangs during ls or mget

  • 7022480
  • 19-Dec-2017
  • 19-Dec-2017

Environment

Open Enterprise Server 2015 (OES 2015) Linux Support Pack 1

Situation

During a FTP session, a user issues an ls or mget command with a file specification, for example:
 
After:
cd /
 
Any of the following would hang:
ls *
ls t*
mget *rpm
 
This only occurs when two conditions are met:
 
a. The FTP session's current working directory appears as a root directory. This is equally true whether it is the true root of the server's file system, or a chrooted location.
 
b. The FTP Server has "remote_server yes" set.  The configuration normally resides in: 
/etc/pure-ftpd/pure-ftpd.conf
 
If the current working directory is not root, it will succeed, even if it references a file under root. For example, the following will succeed:
cd /sub1
ls /file1
 
The ls command without any file spec succeeds. For example, the following will succeed:
cd /
ls
 

Resolution

A fix for this issue is contained in the December 2017 Maintenance update for OES 2015 SP1, which is available as of December 19th.  More specifically, the fix it in the package novell-oes-pure-ftpd, version 1.0.22-33.88.11.

Cause

If
- the current working directory is "/" (root). 
- remote_server feature is enabled. 
- certain wild card operations are performed. 
 
Then the OES FTP server may treat the file specification as a server name rather than a file or directory name. This problem has been corrected.