running nscd as user nobody

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Environment

SUSE Linux Enterprise Server 11 SP2
AppArmor 2.0

Situation

nscd (Name Service Cache Daemon) by default runs as root.
It's prepared to run as unpriviliged user nobody, when configured to do so, nscd can't start.

Resolution

The nscd Apparmor profile is not prepared for that and needs some additional
capabilities added.

Necessary changes are:

/etc/nscd.conf:

        server-user             nobody

/etc/apparmor.d/usr.sbin.nscd

          capability setgid,
          capability setuid,

After adding these lines, restart Apparmor and subsequently nscd

Cause

nscd on SLES11 by default runs as root, thus all directories and files it
needs to access are owned by root.

Specifically the files in the /var/run/nscd directory are problematic.

setgid and setuid capabilities are needed to allow nscd running as nobody to
update the cache files owned by root.

Disclaimer

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