Bug 1408724

Summary:	Xvnc -inetd in wait mode loops when a client connect
Product:	[Fedora] Fedora	Reporter:	Francis.Montagnac
Component:	tigervnc	Assignee:	Jan Grulich <jgrulich>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	25	CC:	bphinz, extras-qa, hdegoede, ipilcher, jgrulich, twaugh
Target Milestone:	---	Keywords:	Regression
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	tigervnc-1.7.0-6.fc25	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:	1293243	Environment:
Last Closed:	2017-01-12 05:24:36 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 Francis.Montagnac 2016-12-26 18:00:44 UTC

+++ This bug was initially created as a clone of Bug #1293243 +++

Description of problem:

    Xvnc -inetd in wait mode loops when a client connect.

Version-Release number of selected component (if applicable):

    tigervnc-server-minimal-1.7.0-5.fc25.x86_64

How reproducible: always

Steps to Reproduce:
    1. install the xinetd package
    2. install the attached vnc-test xinetd service in /etc/xinetd.d
    3. install the attached vnc-test-session in /tmp
       Note: the attachment is in the #1293243 bugzilla
    4. start xinetd
    5. executes: vncviewer localhost &
    6. you will see Xvnc loops

Actual results:

    The Xvnc loops.

Additional info:

This bug it not present in tigervnc-server-minimal-1.7.0-1.fc24.x86_64

Xvnc polls the file descriptor 2 that is opened to /dev/null

lsof -d 0-9 -a -p 12296
COMMAND   PID USER   FD   TYPE             DEVICE SIZE/OFF  NODE NAME
Xvnc    12296 root    0u  IPv6              87422      0t0   TCP localhost:rfb (LISTEN)
Xvnc    12296 root    1u  IPv6              87422      0t0   TCP localhost:rfb (LISTEN)
Xvnc    12296 root    2w   CHR                1,3      0t0  1028 /dev/null
Xvnc    12296 root    3u  IPv6              87422      0t0   TCP localhost:rfb (LISTEN)
Xvnc    12296 root    4u  unix 0xffff94d329f65c00      0t0 86489 @/tmp/.X11-unix/X2 type=STREAM
Xvnc    12296 root    5u  unix 0xffff94d329f67000      0t0 86490 /tmp/.X11-unix/X2 type=STREAM
Xvnc    12296 root    6u  unix 0xffff94d329f63000      0t0 86492 type=DGRAM

strace -s 100  -p 12296 |& head -10
strace: Process 12296 attached
epoll_wait(2, 0x7ffeeb9a6b20, 256, 542134) = -1 EINVAL (Invalid argument)
write(2, "WaitForSomething(): poll: Invalid argument\n", 43) = 43
epoll_wait(2, 0x7ffeeb9a6b20, 256, 542134) = -1 EINVAL (Invalid argument)
write(2, "WaitForSomething(): poll: Invalid argument\n", 43) = 43
epoll_wait(2, 0x7ffeeb9a6b20, 256, 542134) = -1 EINVAL (Invalid argument)
write(2, "WaitForSomething(): poll: Invalid argument\n", 43) = 43
epoll_wait(2, 0x7ffeeb9a6b20, 256, 542134) = -1 EINVAL (Invalid argument)
write(2, "WaitForSomething(): poll: Invalid argument\n", 43) = 43
epoll_wait(2, 0x7ffeeb9a6b20, 256, 542134) = -1 EINVAL (Invalid argument)

Comment 1 Francis.Montagnac 2016-12-27 18:41:55 UTC

This bug shows up also with tigervnc-server-minimal-1.7.0-3.fc25

Comment 2 Ian Pilcher 2017-01-05 03:36:13 UTC

I've managed to rebuild tigervnc-1.6.0-6.fc24.src.rpm for Fedora 25, and it appears to work.  In order to build from the older SRPM, I had to install xorg-x11-server-source-1.18.4-5.fc24.noarch (rather than the F25 package).

Comment 3 Ian Pilcher 2017-01-05 15:47:36 UTC

I just built 1.7.0 from git.  I followed the upstream directions and used xorg-x11-server-source-1.18.4-5.fc24.noarch.  Lo and behold, it works just fine.

So this appears to be related to the 1.19 compatibility patches (or to 1.19 itself).

Comment 4 Ian Pilcher 2017-01-05 16:01:02 UTC

In fact, simply installing xorg-x11-server-source-1.18.4-5.fc24.noarch on a Fedora 25 system and rebuilding tigervnc-1.7.0-5.fc25.src.rpm (with rpmbuild, not in mock) produces a working binary.

Comment 5 Jan Grulich 2017-01-06 06:16:18 UTC

Thanks for your investigation, to me it appears that this is broken either because of changes made to support XServer 1.19 or because of XServer 1.19 itself.

@Hans, any idea what could be the reason why this is broken with XServer 1.19?

Comment 6 Hans de Goede 2017-01-09 16:17:39 UTC

Hi,

(In reply to Jan Grulich from comment #5)
> Thanks for your investigation, to me it appears that this is broken either
> because of changes made to support XServer 1.19 or because of XServer 1.19
> itself.
> 
> @Hans, any idea what could be the reason why this is broken with XServer
> 1.19?

I had to debug things a bit, but I've found the culprit, this patch fixes this:

http://pkgs.fedoraproject.org/cgit/rpms/tigervnc.git/tree/0001-Fix-inetd-not-working-with-xserver-1.19.patch

I'm preparing an F25 update with the fix.

Regards,

Hans

Comment 7 Fedora Update System 2017-01-09 17:07:42 UTC

tigervnc-1.7.0-6.fc25 has been submitted as an update to Fedora 25. https://bodhi.fedoraproject.org/updates/FEDORA-2017-5758dfef76

Comment 8 Fedora Update System 2017-01-10 03:28:17 UTC

tigervnc-1.7.0-6.fc25 has been pushed to the Fedora 25 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-5758dfef76

Comment 9 Jan Grulich 2017-01-10 06:22:26 UTC

Thank you so much Hans for the fix.

Comment 10 Francis.Montagnac 2017-01-11 16:52:48 UTC

I confirm that it works also for me.

Thanks a lot.

Comment 11 Fedora Update System 2017-01-12 05:24:36 UTC

tigervnc-1.7.0-6.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.