On Wed, 27 May 2015 12:20, blue hut wrote:
On 05/27/2015 12:16 PM, Carlos E. R. wrote:
On 2015-05-26 21:19, blue hut wrote:
Hi,
upgraded to Tumbleweed from 13.2 today. No problems, except this one: lightdm didn't start my xfce anymore, first I thought its a problem in lightdm, then I realized that s bit was missing from /usr/bin/Xorg. After setting it, all works as expected.
Just wanted to let you know. That bit is intentionally unset since 11.X or thereabouts. In the /etc/permissions.local you see this note since years:
# setuid bit on Xorg is only needed if no display manager, ie startx # is used. Beware of CVE-2010-2240. # # /usr/bin/Xorg root:root 4711
Alright. But I still don't get why I had to set it to get lightdm to start xfce. Like I said, I was on 13.2 and switched to Tumbleweed yesterday. After rebooting the display manager couldn't start any DE anymore. After setting the bit, it worked.
A shot in the dark, but as which user is lightdm running? Running as "root", no suid bit is needed, the rights are sufficent, running as e.g. user "lightdm" and the rights remaining may not be sufficent to start the xserver for the user that wants to login. Background: A program can be started as root, and then drop any rights and capabilities it does not need and change userid to a less privileged user. See e.g. "apache2" on how that is done right. Either lightdm is started directly as a less privileged user, then it will never have the needed rights, and suid on Xorg is the way to go without changeing systemd-service-files. (drop-in snippets ftw) Or, lightdm is started as root and drops to much privileges, then it is a bug, that has to be addressed, and suid on Xorg is just the crutch until it's fixed. What exactly happend in your case, I can not say. - Yamaban. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org