Bug 843185

Summary:	ISC dhcp server terminates because of lease time set to 0xffffffff (infinity)
Product:	[Fedora] Fedora	Reporter:	Pavel Šimerda (pavlix) <psimerda>
Component:	dhcp	Assignee:	Jiri Popelka <jpopelka>
Status:	CLOSED DUPLICATE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	17	CC:	jpopelka, pbrobinson, thozza
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-07-26 07:47:49 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Pavel Šimerda (pavlix) 2012-07-25 20:04:39 UTC

When testing bug 662254 I realised there is a similar problem in the server side
of ISC DHCP.

662254

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:

1. Prepare a clean client and a clean server

client# rm /var/lib/dhclient/dhclient.leases

server# rm /var/lib/dhcpd/dhcpd.leases
server# touch /var/lib/dhcpd/dhcpd.leases

2. Prepare server's /etc/dhcp/dhcpd.conf (make sure to use the correct subnet)

option domain-name "example.org";
option domain-name-servers 8.8.8.8;

default-lease-time 0xffffffff;
max-lease-time 0xffffffff;

subnet 192.168.25.0 netmask 255.255.255.0 {
range dynamic-bootp 192.168.25.10 192.168.25.20;
option routers 192.168.25.1;
}

3. Start/restart dhcp server

service dhcpd restart

4. Start dhcp client from commandline

dhclient eth1

5. Observe the server logs...

Jul 25 21:57:40 router dhcpd: DHCPDISCOVER from 52:54:00:eb:e9:fb via eth1
Jul 25 21:57:41 router dhcpd: DHCPOFFER on 192.168.25.10 to 52:54:00:eb:e9:fb via eth1
Jul 25 21:57:41 router dhcpd: DHCPREQUEST for 192.168.25.10 (192.168.25.1) from 52:54:00:eb:e9:fb via eth1
Jul 25 21:57:41 router dhcpd: DHCPACK on 192.168.25.10 to 52:54:00:eb:e9:fb via eth1

So far so good.

6. Restart the DHCP client

client# killall dhclient
client# dhclient eth1

7. Observe the server logs...

Jul 25 22:01:31 router dhcpd: Unable to set up timer: out of range
Jul 25 22:01:31 router dhcpd:
Jul 25 22:01:31 router dhcpd: This version of ISC DHCP is based on the release available
Jul 25 22:01:31 router dhcpd: on ftp.isc.org. Features have been added and other changes
Jul 25 22:01:31 router dhcpd: have been made to the base software release in order to make
Jul 25 22:01:31 router dhcpd: it work better with this distribution.
Jul 25 22:01:31 router dhcpd:
Jul 25 22:01:31 router dhcpd: Please report for this software via the Red Hat Bugzilla site:
Jul 25 22:01:31 router dhcpd: http://bugzilla.redhat.com
Jul 25 22:01:31 router dhcpd:
Jul 25 22:01:31 router dhcpd: exiting.

dhcp-4.2.4-0.4.rc1.fc17.x86_64

Comment 1 Pavel Šimerda (pavlix) 2012-07-25 21:33:04 UTC

A very simple and stupid patch seems to work around for me:

Index: dhcp-4.2.4-P1/common/dispatch.c
===================================================================
--- dhcp-4.2.4-P1.orig/common/dispatch.c
+++ dhcp-4.2.4-P1/common/dispatch.c
@@ -320,6 +320,11 @@ void add_timeout (when, where, what, ref
 	q->next  = timeouts;
 	timeouts = q;
 
+#define MAX 0x10000
+
+	if (sec >= MAX)
+		sec = MAX;
+
 	isc_interval_set(&interval, sec & DHCP_SEC_MAX, usec * 1000);
 	status = isc_time_nowplusinterval(&expires, &interval);
 	if (status != ISC_R_SUCCESS) {

This is not a proper fix but it keeps DHCP server running. You can tweak the value of course.

If you want to play with it, you can use a scratch build of mine before a proper fix is out:

http://koji.fedoraproject.org/koji/taskinfo?taskID=4329834

Comment 2 Jiri Popelka 2012-07-26 01:53:07 UTC

Most likely a duplicate of bug #789601 (the security-flag should be removed soon).

Can you test this scratch-build ?
http://koji.fedoraproject.org/koji/taskinfo?taskID=4330107

Comment 3 Pavel Šimerda (pavlix) 2012-07-26 07:47:49 UTC

I confirm DHCP server now DHCPACK's the lease and continues to run with:

Jul 26 09:43:02 router dhcpd: Timeout requested too large reducing to 2^^32-10
Jul 26 09:43:02 router dhcpd: DHCPREQUEST for 192.168.25.10 from 52:54:00:eb:e9:fb (station) via eth1
Jul 26 09:43:02 router dhcpd: DHCPACK on 192.168.25.10 to 52:54:00:eb:e9:fb (station) via eth1

Next dhclient run just:

Jul 26 09:44:29 router dhcpd: DHCPREQUEST for 192.168.25.10 from 52:54:00:eb:e9:fb (station) via eth1
Jul 26 09:44:29 router dhcpd: DHCPACK on 192.168.25.10 to 52:54:00:eb:e9:fb (station) via eth1

*** This bug has been marked as a duplicate of bug 789601 ***

Comment 4 Peter Robinson 2012-07-26 08:22:20 UTC

> *** This bug has been marked as a duplicate of bug 789601 ***

That bug is restricted access. Please open the bug for general access.