RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 693381 - dhcpd running as root
Summary: dhcpd running as root
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: dhcp
Version: 6.1
Hardware: All
OS: Linux
medium
medium
Target Milestone: rc
: ---
Assignee: Jiri Popelka
QA Contact: Release Test Team
URL:
Whiteboard:
Depends On: 699713 737571
Blocks: 743047 748554
TreeView+ depends on / blocked
 
Reported: 2011-04-04 13:52 UTC by Marko Myllynen
Modified: 2011-12-06 12:00 UTC (History)
6 users (show)

Fixed In Version: dhcp-4.1.1-25.P1.el6
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2011-12-06 12:00:32 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2011:1597 0 normal SHIPPED_LIVE dhcp bug fix and enhancement update 2011-12-06 00:51:17 UTC

Description Marko Myllynen 2011-04-04 13:52:02 UTC 
Description of problem:
On RHEL/Fedora dhcpd seems to be running as root although on some other widely used distributions it is running as a non-root user which is very favourable from the security point of view.

Please consider running dhcpd as non-root.

Version-Release number of selected component (if applicable):
RHEL 6.0 / RHEL 6.1 Beta
Comment 2 RHEL Program Management 2011-04-04 13:54:53 UTC 
Since RHEL 6.1 External Beta has begun, and this bug remains
unresolved, it has been rejected as it is not proposed as
exception or blocker.

Red Hat invites you to ask your support representative to
propose this request, if appropriate and relevant, in the
next release of Red Hat Enterprise Linux.
Comment 3 Jiri Popelka 2011-04-05 14:43:41 UTC 
AFAICT dhcpd needs to be run as superuser because of using of SOCK_RAW sockets.

When you try to run dhcpd as non-root you get:
'unable to create icmp socket: Operation not permitted'

Can you be more specific in what distributions do you have in mind ?
I have tried debian stable with exactly the same results as on RHEL/Fedora,
i.e. you need to be root to start the dhcp server service (called isc-dhcp-server) or directly dhcpd there.
Comment 4 Marko Myllynen 2011-04-05 15:37:29 UTC 
> Can you be more specific in what distributions do you have in mind ?

On Ubuntu dhcpd is running as user dhcpd. Interestingly, on Debian dhcpd indeed runs as root.

This is definitely in the nice-to-have category but Ubuntu has a patch to use capabilities in order to be able to drop root privileges, see:

http://packages.ubuntu.com/natty/isc-dhcp-server
http://archive.ubuntu.com/ubuntu/pool/main/i/isc-dhcp/isc-dhcp_4.1.1-P1-15ubuntu6.diff.gz

I'm CC'ing sgrubb how can possibly comment whether it would make sense for us too to use capabilities to drop root privileges with dhcpd?

Thanks.
Comment 6 Jiri Popelka 2011-04-26 12:52:11 UTC 
This seems to be a significant change which should be implemented upstream (in Fedora) first.
Cloned for Fedora as bug #699713
and closing this as UPSTREAM.

Thank you for the report.
Comment 7 Marko Myllynen 2011-09-12 09:53:18 UTC 
Reopening for discussion about backporting this since upstream/Fedora has rootless dhcpd feature now available (bug 699713).

Although there are no known customer requests for this yet backporting this might well make sense given that RHEL 6 still has almost 6.5+3 years left as supported platform.
Comment 20 errata-xmlrpc 2011-12-06 12:00:32 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2011-1597.html
Note You need to log in before you can comment on or make changes to this bug.