[SOLVED] sudo gui apps cannot connect to xserver from terminal app

daedalusman · 2010-08-27 22:03:09

I just started getting this error about a week ago.

sudo kwrite /etc/pacman.conf
Password: 
No protocol specified
kwrite: cannot connect to X server :0.0

Prior to that time this worked just as it would without the sudo command preempting, it would just run the gui application. I made no configuration changes but I have updated my system in that time period. Was there a change to sudo or somewhere in KDE that would cause this change in behavior? Or is there something I can do to get this working like it used to a few weeks ago?

Thanks for any help.

Last edited by daedalusman (2010-08-29 20:04:45)

keripix · 2010-08-28 01:04:52

maybe you could use:

kdesu kwrite /etc/pacman.conf

*vitali* · 2010-08-28 01:32:17

run "xhost +".
I added this to kde autostart, you should now be able to launch all GUI program from root.

daedalusman · 2010-08-28 04:47:52

*vitali* wrote:

run "xhost +".
I added this to kde autostart, you should now be able to launch all GUI program from root.

I have never done this before and up until about a week ago I never had this problem. So why would I have to do this now?

Labello · 2010-08-28 08:21:42

keripix wrote:

maybe you could use:
kdesu kwrite /etc/pacman.conf

this is the right way to go!

mir · 2010-08-28 09:08:06

Last time I checked kdesu had nothing like /etc/sudoers, or does it have something similar?

Last edited by mir (2010-08-28 09:08:23)

tsv · 2010-08-28 09:17:18

Not 100%, but I think this is actually a feature, to prevent random users using your X display. If you use the xhost route, it could make it possible for other users to launch programs to your X session (perhaps over SSH), So yes kdesu / gksu are the recommended path. Don't actually use them myself though, so I'm afraid I can't speak as to features.

PirateJonno · 2010-08-28 11:24:16

daedalusman wrote:

I have never done this before and up until about a week ago I never had this problem. So why would I have to do this now?

Sudo was updated recently, and no longer preserves some environment variables like HOME. See the /etc/sudoers file for details (it says how to fix this too). I'm not sure which is less secure - preserving HOME or running xhost + all the time...

Last edited by PirateJonno (2010-08-28 11:25:55)

*vitali* · 2010-08-28 16:09:44

How about a bashrc alias sort of like
alias sudo='A=`alias` sudo '
alias kwrite="xhost +; kwrite; xhost -"
alias kate="xhost +; kate; xhost -"
except it won't take arguments anymore.....

flamelab · 2010-08-28 16:55:58

xhost + and sudo is not a good security options for launching gui apps. It would be much better to use kdesu .

mir · 2010-08-29 17:05:42

Don't do "xhost +" without understanding the implications.

I found out that adding

"DISPLAY XAUTHORITY"

to the "env_keep" defaults (in /etc/sudoers) works

See

man Xsecurity

Last edited by mir (2010-08-29 17:08:04)

RobertMe · 2010-08-29 17:53:41

mir wrote:

Last time I checked kdesu had nothing like /etc/sudoers, or does it have something similar?

kdesu can use sudo instead of su to gain root access. See the sudo wiki page for instructions how to do this.

Vamp898 · 2010-08-29 19:42:08

A lot of people have this problem and its very easy to solve

The Solution is, read the pacman messages at upgrade

the last upgrade of sudo told you that there is a new /etc/sudoers and there is a lot of new content in it

If you read the Comments in the "new" sudoers file you´ll find out to enable X support in seconds

Its even that easy that you just have to uncomment the already prepared lines. Really, people often ignore the "New .pacnew file" messages when upgrading there system or just delete them... its not good at all...

also you should rename the title cause this happens in GNOME and every other DE/WM too

Last edited by Vamp898 (2010-08-29 19:42:40)

daedalusman · 2010-08-29 20:04:06

Thanks, Vamp898 and PirateJonno, I missed that message about the new sudoers file. Everything is back to how I like it.

mir · 2010-08-29 21:11:50

Hmm, I found HOME unnecessary and confusing. XAUTHORITY containts the full path to the cookie file. so there's no need to keep HOME.

Just my 2c ...

shervinkh · 2011-01-11 22:10:25

Thank You So Much.I Solved It With /etc/sudoers.pacnew

Arch Linux

#1 2010-08-27 22:03:09

[SOLVED] sudo gui apps cannot connect to xserver from terminal app

#2 2010-08-28 01:04:52

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#3 2010-08-28 01:32:17

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#4 2010-08-28 04:47:52

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#5 2010-08-28 08:21:42

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#6 2010-08-28 09:08:06

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#7 2010-08-28 09:17:18

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#8 2010-08-28 11:24:16

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#9 2010-08-28 16:09:44

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#10 2010-08-28 16:55:58

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#11 2010-08-29 17:05:42

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#12 2010-08-29 17:53:41

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#13 2010-08-29 19:42:08

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#14 2010-08-29 20:04:06

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#15 2010-08-29 21:11:50

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

#16 2011-01-11 22:10:25

Re: [SOLVED] sudo gui apps cannot connect to xserver from terminal app

Board footer