Bug 820876

Summary:	vsftpd DNS lookup cannot be disabled
Product:	Red Hat Enterprise Linux 6	Reporter:	Sebastien Caps <sebastien.caps>
Component:	vsftpd	Assignee:	Jiri Skala <jskala>
Status:	CLOSED DUPLICATE	QA Contact:	BaseOS QE Security Team <qe-baseos-security>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	6.2	CC:	aglotov, ovasik
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-05-11 10:15:57 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Sebastien Caps 2012-05-11 09:30:33 UTC

Description of problem:
vsftpd DNS lookup cannot be disabled.
This bug have been resolv in 5.x with the option 'reverse_lookup_enable'
but in 6.2 this option is no longer available

https://rhn.redhat.com/errata/RHBA-2009-1282.html :
...
* the DNS reverse lookup feature was implemented without any way to disable
it. This update contains the parameter 'reverse_lookup_enable', which
allows users to enable or disable the DNS reverse lookup functionality.
(BZ#498548) 
...
Version-Release number of selected component (if applicable):
rpm -qi vsftpd
Name : vsftpd Relocations: (not relocatable)
Version : 2.2.2 
Release : 6.el6_2.1

How reproducible:
ALWAYS
Steps to Reproduce:
1. having 2(or more) nameserver in /etc/resolv.conf that is NOT reachable
2. and then try to connect to the ftp server.
  
Actual results:
Connection timed out

Expected results:
Connection succesfull

Additional info:
trying with "reverse_lookup_enable=NO"
service vsftpd restart
Shutting down vsftpd: [FAILED]
Starting vsftpd for vsftpd: 500 OOPS: unrecognised variable in config file: reverse_lookup_enable
                                                           [FAILED]

Comment 2 Jiri Skala 2012-05-11 10:15:57 UTC

The fix will be available in the next update 6.3.

*** This bug has been marked as a duplicate of bug 752954 ***