Bug 479481

Summary:	KDE applications cannot be launched from konsole after su to another user
Product:	[Fedora] Fedora	Reporter:	Need Real Name <k.j.nash>
Component:	kdebase	Assignee:	Than Ngo <than>
Status:	CLOSED DUPLICATE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	low
Version:	10	CC:	jreznik, kevin, lorenzo, ltinkl, rdieter, than, tuxbrewr
Target Milestone:	---
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2009-01-10 18:50:59 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Need Real Name 2009-01-09 22:43:04 UTC

Description of problem:

KDE applications cannot be launched from konsole after su to another user.
This appears to be related to the value of DBUS_SESSION_BUS_ADDRESS

Version-Release number of selected component (if applicable):
kdebase-4.1.3-2.fc10.x86_64
coreutils-6.12-18.fc10.x86_64

How reproducible:
Always

Steps to Reproduce:
1. start konsole
2. su fred # any user, root or non-root
3. kwrite
  
Actual results:

kwrite hangs with no output to konsole and no display.
similar results with dolphin, kate
This is not an X11 authentication problem - non-KDE X11 apps have no problem.

Expected results:

kwrite opens in its own window

Fix:

Run this command before launching kwrite:
export DBUS_SESSION_BUS_ADDRESS=

(I found that I could launch KDE applications as another user by switching user with ssh; I compared the environments created by ssh and su, and discovered this fix by trial and error.)

Additional info:

System installed from x86_64 live CD to fresh partition, SELinux disabled, many more RPMs installed with yum.  All components up to date with yum mirrors at
Fri Jan  9 22:25:07 GMT 2009

Comment 1 Rex Dieter 2009-01-10 00:45:32 UTC

Nice workaround, but what do you expect us to do with this information?

Comment 2 Need Real Name 2009-01-10 18:04:40 UTC

This bug is a regression - this method of launching KDE applications as a different user worked with KDE 3 in Fedora 8 and earlier.

I am not sufficiently knowledgeable about the KDE/DBUS ecosystem to know where exactly the bug lies.  However, I am sure that one of the Fedora maintainers will have that knowledge, and if the bug is considered sufficiently important, he/she will consider fixing it.

My workaround suggests that the problem lies in the interaction between KDE4 and DBUS, but does not come with any greater understanding than that. I thought you'd rather have the information than not have it.

Keith.

Comment 3 Kevin Kofler 2009-01-10 18:50:59 UTC

Running GUI apps under su has never been a good idea, I've seen all sorts of problems caused by it in KDE 3, like permissions on Unix sockets used by KDE getting screwed up.

That's what kdesu is for (currently /usr/libexec/kde4/kdesu, we're going to replace the broken KDE 3 /usr/bin/kdesu with a symlink to that in the KDE 4.2 update, maybe already in an earlier update).

*** This bug has been marked as a duplicate of bug 473465 ***

Comment 4 Kevin Kofler 2009-01-10 18:51:26 UTC

(Oh, and your workaround is not a fix.)

Comment 5 Need Real Name 2009-01-11 00:29:30 UTC

Re #4: fair comment.