Ubuntu

Comment 0 for bug 423252

On Karmic (alpha 4 plus updates), changing the nsswitch.conf 'passwd' field to anything with 'ldap' as the first item breaks the ability to become root using 'su' and 'sudo' as anyone but root.

Default nsswitch.conf:

passwd: compat
group: compat
shadow: compat

matt@box:~$ sudo uname -a
[sudo] password for matt:
Linux box 2.6.31-9-server #29-Ubuntu SMP Sun Aug 30 18:37:42 UTC 2009 x86_64 GNU/Linux

matt@box:~$ su -
Password:
root@box:~#

Modified nsswitch.conf with 'ldap' before 'compat':

passwd: ldap compat
group: ldap compat
shadow: ldap compat

matt@box:~$ sudo uname -a
sudo: setreuid(ROOT_UID, user_uid): Operation not permitted

matt@box:~$ su -
Password:
setgid: Operation not permitted

Modified nsswitch.conf with 'ldap' after 'compat':

passwd: compat ldap
group: compat ldap
shadow: compat ldap

matt@box:~$ sudo uname -a
[sudo] password for matt:
Linux box 2.6.31-9-server #29-Ubuntu SMP Sun Aug 30 18:37:42 UTC 2009 x86_64 GNU/Linux

matt@box:~$ su -
Password:
root@box:~#

The same arrangements in nsswitch.conf work as expected in Jaunty and earlier releases.