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Bug 1791996 - TigerVNC should not arbitrarily start on unspecified ports
Summary: TigerVNC should not arbitrarily start on unspecified ports
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: tigervnc
Version: 7.7
Hardware: x86_64
OS: Linux
unspecified
medium
Target Milestone: rc
: ---
Assignee: Jan Grulich
QA Contact: Desktop QE
URL:
Whiteboard:
Depends On:
Blocks: 1789022 2174398
TreeView+ depends on / blocked
 
Reported: 2020-01-16 20:20 UTC by Joe Wright
Modified: 2023-12-15 17:11 UTC (History)
5 users (show)

Fixed In Version: tigervnc-1.8.0-20.el7
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
: 2174398 (view as bug list)
Environment:
Last Closed: 2020-09-29 19:28:00 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Knowledge Base (Solution) 5455791 0 None None None 2020-10-01 14:13:43 UTC
Red Hat Product Errata RHSA-2020:3875 0 None None None 2020-09-29 19:28:20 UTC

Description Joe Wright 2020-01-16 20:20:07 UTC 
Description of problem:
- TigerVNC should not start on unspecified ports if it fails to start on the defined port

Version-Release number of selected component (if applicable):
tigervnc-1.3.1-9.el7

How reproducible:
100%. This behavior was introduced by ERRATA RHBA-2016-2237

Steps to Reproduce:
1. configure VNC to start on a port that is already in use
2. Observe that it goes through ports until it finds one that is available to start on
3.

Actual results:
VNC opens on the first available port it can find when it fails on the defined port

Expected results:
VNC should not be opening on the first port it can find when it cannot open on the specified port

Additional info:
Comment 8 Martin Krajnak 2020-04-27 14:09:14 UTC 
tigervnc-1.8.0-21.el7.x86_64

1.Reproducer
[test@beaker-tigervnc-develop-325 tigervnc]$ vncserver :1      

New 'beaker-tigervnc-develop-325:1 (test)' desktop is beaker-tigervnc-develop-325:1

Starting applications specified in /home/test/.vnc/xstartup
Log file is /home/test/.vnc/beaker-tigervnc-develop-325:1.log

[test@beaker-tigervnc-develop-325 tigervnc]$ vncserver :1
A VNC server is already running as :1

Result:
I was able to connect to the session via vncviewer :1.


2.Reproducer
[test@beaker-tigervnc-develop-325 tigervnc]$ vncserver :1 -fallbacktofreeport
A VNC server is already running as :1
Using port :2 as fallback

New 'beaker-tigervnc-develop-325:2 (test)' desktop is beaker-tigervnc-develop-325:2

Starting applications specified in /home/test/.vnc/xstartup
Log file is /home/test/.vnc/beaker-tigervnc-develop-325:2.log

Result:
I was able to connect to the session via vncviewer :2.
Comment 10 errata-xmlrpc 2020-09-29 19:28:00 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (Moderate: tigervnc security and bug fix update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2020:3875
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