Report information
The Basics
Id:
25601
Status:
open
Worked:
20 minutes
Priority:
Medium/Medium
Queue:

People
Owner:
Nobody in particular
Cc:
AdminCc:

BugTracker
Version Fixed:
(no value)
Version Found:
(no value)
Versions Affected:
(no value)
Versions Planned:
(no value)
Priority:
(no value)
Severity:
S3 Low
CVSS Score:
(no value)
CVE ID:
(no value)
Component:
DHCP Server
Area:
bug

Dates
Created:Thu, 25 Aug 2011 01:45:18 -0400
Updated:Fri, 07 Jul 2017 01:28:44 -0400
Closed:Not set



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CC: gdiener@excelii.com, 627136-forwarded@bugs.debian.org, 627136@bugs.debian.org
Subject: [gdiener@excelii.com: Bug#627136: isc-dhcp-server: dhcpd segfaults on config with multiple empty lines]
Date: Wed, 24 Aug 2011 22:44:22 -0700
To: dhcp-bugs@isc.org
From: Andrew Pollock <apollock@debian.org>
Hello, A user reported this bug to us a while ago. I can reproduce it with the configuration included below on 4.2.2, just by using the -t option. Please maintain the Cc of this email to keep our bug tracking system in the loop. regards Andrew ----- Forwarded message from Glen Diener <gdiener@excelii.com> ----- Date: Tue, 17 May 2011 17:07:49 -0500 From: Glen Diener <gdiener@excelii.com> To: Debian Bug Tracking System <submit@bugs.debian.org> Subject: Bug#627136: isc-dhcp-server: dhcpd segfaults on config with multiple empty lines X-Mailer: reportbug 4.12.6 Package: isc-dhcp-server Version: 4.1.1-P1-15+squeeze2 Severity: important The dhcpd server dies with segmentation fault when the dhcpd.conf file contains numerous consecutive blank lines. In my case, the dhcpd.conf had 100 consecutive lines with 23 spaces. The server will exhibit the same behavior with 1507 or more consecutive blank lines. The relevant contents of /var/log/syslog follow: May 17 15:45:41 buddy dhcpd: Internet Systems Consortium DHCP Server 4.1.1-P1 May 17 15:45:41 buddy dhcpd: Copyright 2004-2010 Internet Systems Consortium. May 17 15:45:41 buddy dhcpd: All rights reserved. May 17 15:45:41 buddy dhcpd: For info, please visit https://www.isc.org/software/dhcp/ May 17 15:45:41 buddy kernel: [29319.970678] dhcpd[15683]: segfault at 1003549 ip 00000000004414bc sp 00007fff74979718 error 4 in dhcpd[400000+a7000] I suspect a buffer overflow problem when the amount of white space between configuration directives reaches a threshold. -- System Information: Debian Release: 6.0.1 APT prefers stable APT policy: (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 2.6.32-5-amd64 (SMP w/1 CPU core) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Versions of packages isc-dhcp-server depends on: ii debconf [debconf-2. 1.5.36.1 Debian configuration management sy ii debianutils 3.4 Miscellaneous utilities specific t ii isc-dhcp-common 4.1.1-P1-15+squeeze2 common files used by all the isc-d ii libc6 2.11.2-10 Embedded GNU C Library: Shared lib ii lsb-base 3.2-23.2squeeze1 Linux Standard Base 3.2 init scrip isc-dhcp-server recommends no packages. Versions of packages isc-dhcp-server suggests: pn isc-dhcp-server-ldap <none> (no description available) -- Configuration Files: /etc/dhcp/dhcpd.conf changed: authoritative; option domain-name "internal.excelhustler.com"; option domain-name-servers 192.168.0.2; option wpad code 252 = text; option wpad "http://wpad.internal.hustlerturf.com/wpad.dat"; option systemimager-server code 140 = text; option systemimager-server "192.168.0.8"; option space gpxe; option gpxe-encap-opts code 175 = encapsulate gpxe; option gpxe.bus-id code 177 = string; option gpxe.keep-san code 8 = unsigned integer 8; option subnet-mask 255.255.0.0; default-lease-time 172800; max-lease-time 345600; allow duplicates; # Seems to be needed for Mac clients subnet 192.168.0.0 netmask 255.255.0.0 { option broadcast-address 192.168.255.255; option routers 192.168.0.1; } host rgomez.desktop.internal.excelhustler.com { # This machine belongs to rgomez # This machine is: PG030911005191 # Ethernet vendor is: Unknown hardware ethernet 00:e0:4c:a8:78:c0; fixed-address 192.168.5.3; next-server 192.168.0.61; filename "pxelinux.0"; } -- debconf information excluded ----- End forwarded message -----

Message body not shown because it is not plain text.

On Thu Aug 25 05:45:18 2011, apollock@debian.org wrote:
> Hello,
>
> A user reported this bug to us a while ago. I can reproduce it with
> the configuration included below on 4.2.2, just by using the -t option.

Andrew --

I've confirmed that dhcpd behaves as you have described -- thanks for the
useful characterization of the bug, it made it much easier to reproduce --
and forwarded it to our dev team along with conf files which trigger it.

Thanks for reporting it.

Michael McNally
ISC Support