host[47240]: segfault at 1f ip 00007f8c5a00db0c sp 00007f8c56bf7e20 error 6 in host.orig[7f8c5a001000+1a000]

[Ralf Hildebrandt]

On our nagios/centreon server, the host command is crashing from time to time.
In order to find out what query causes "host" to crash, I wrapped host into a bash shell script:

Apr 22 07:36:01 nagios-netz kernel: [7646451.019916] host.orig[21971]: segfault at 1f ip 00007f8233a5bb0c sp 00007f8230645e20 error 6 in host.orig[7f8233a4f000+1a000]
Apr 22 07:36:01 nagios-netz logger: Error: Command [ /usr/bin/host.orig 35.206.42.141.combined.njabl.org ] returned 139

Apr 22 07:51:01 nagios-netz kernel: [7647350.025178] host.orig[27152]: segfault at 1f ip 00007f1f140d6b0c sp 00007f1f10cc0e20 error 6 in host.orig[7f1f140ca000+1a000]
Apr 22 07:51:01 nagios-netz logger: Error: Command [ /usr/bin/host.orig 35.206.42.141.combined.njabl.org ] returned 139

Apr 22 07:58:39 nagios-netz kernel: [7647807.508337] host.orig[29693]: segfault at 1f ip 00007f6bba66bb0c sp 00007f6bb7255e20 error 6 in host.orig[7f6bba65f000+1a000]
Apr 22 07:58:39 nagios-netz logger: Error: Command [ /usr/bin/host.orig 208.73.175.193.combined.njabl.org ] returned 139
Apr 22 07:58:50 nagios-netz kernel: [7647818.577504] host.orig[29718]: segfault at 1f ip 00007fe0c53f6b0c sp 00007fe0c1fe0e20 error 6 in host.orig[7fe0c53ea000+1a000]
Apr 22 07:58:50 nagios-netz logger: Error: Command [ /usr/bin/host.orig 208.73.175.193.dnsbl.njabl.org ] returned 139

Apr 22 08:30:05 nagios-netz kernel: [7649692.695913] host.orig[41538]: segfault at 1f ip 00007fe6be9aeb0c sp 00007fe6bb598e20 error 6 in host.orig[7fe6be9a2000+1a000]
Apr 22 08:30:05 nagios-netz logger: Error: Command [ /usr/bin/host.orig 209.73.175.193.dnsbl.njabl.org ] returned 139

Apr 22 08:38:50 nagios-netz kernel: [7650217.411805] host.orig[44547]: segfault at 1f ip 00007f5a847e8b0c sp 00007f5a813d2e20 error 6 in host.orig[7f5a847dc000+1a000]
Apr 22 08:38:50 nagios-netz logger: Error: Command [ /usr/bin/host.orig 208.73.175.193.dnsbl.njabl.org ] returned 139

Apr 22 08:49:54 nagios-netz kernel: [7650881.020604] host.orig[48422]: segfault at 1f ip 00007f9b17077b0c sp 00007f9b13c61e20 error 6 in host.orig[7f9b1706b000+1a000]
Apr 22 08:49:54 nagios-netz logger: Error: Command [ /usr/bin/host.orig 209.73.175.193.combined.njabl.org ] returned 139

Apr 22 09:41:02 nagios-netz kernel: [7653946.424708] host.orig[1972]: segfault at 1f ip 00007fe230b11b0c sp 00007fe22d6fbe20 error 6 in host.orig[7fe230b05000+1a000]
Apr 22 09:41:02 nagios-netz logger: Error: Command [ /usr/bin/host.orig 35.206.42.141.combined.njabl.org ] returned 139

Apr 22 10:15:06 nagios-netz kernel: [7655989.190830] host.orig[14658]: segfault at 1f ip 00007f0dc6916b0c sp 00007f0dc3500e20 error 6 in host.orig[7f0dc690a000+1a000]
Apr 22 10:15:06 nagios-netz logger: Error: Command [ /usr/bin/host.orig 209.73.175.193.dnsbl.njabl.org ] returned 139

Apr 22 10:23:38 nagios-netz kernel: [7656500.832449] host.orig[17654]: segfault at 1f ip 00007fab9abb0b0c sp 00007fab9779ae20 error 6 in host.orig[7fab9aba4000+1a000]
Apr 22 10:23:38 nagios-netz logger: Error: Command [ /usr/bin/host.orig 208.73.175.193.combined.njabl.org ] returned 139

Apr 22 10:55:07 nagios-netz kernel: [7658389.023423] host.orig[28471]: segfault at 1f ip 00007f1925df5b0c sp 00007f19229dfe20 error 6 in host.orig[7f1925de9000+1a000]
Apr 22 10:55:07 nagios-netz logger: Error: Command [ /usr/bin/host.orig 209.73.175.193.dnsbl.njabl.org ] returned 139

Apr 22 11:33:50 nagios-netz kernel: [7660710.279109] host.orig[42828]: segfault at 1f ip 00007efe6eb27b0c sp 00007efe6b711e20 error 6 in host.orig[7efe6eb1b000+1a000]
Apr 22 11:33:50 nagios-netz logger: Error: Command [ /usr/bin/host.orig 208.73.175.193.dnsbl.njabl.org ] returned 139

Apr 22 11:46:13 nagios-netz kernel: [7661452.829980] host.orig[47240]: segfault at 1f ip 00007f8c5a00db0c sp 00007f8c56bf7e20 error 6 in host.orig[7f8c5a001000+1a000]
Apr 22 11:46:13 nagios-netz logger: Error: Command [ /usr/bin/host.orig 35.206.42.141.dnsbl.njabl.org ] returned 139

Apr 22 12:20:08 nagios-netz kernel: [7663486.330496] host.orig[60333]: segfault at 1f ip 00007f6bb796fb0c sp 00007f6bb4559e20 error 6 in host.orig[7f6bb7963000+1a000]
Apr 22 12:20:08 nagios-netz logger: Error: Command [ /usr/bin/host.orig 209.73.175.193.dnsbl.njabl.org ] returned 139

The queries itself take quite some time when run manually:

# time /usr/bin/host.orig 209.73.175.193.dnsbl.njabl.org
Host 209.73.175.193.dnsbl.njabl.org not found: 3(NXDOMAIN)

real 0m12.008s
user 0m0.000s
sys 0m0.004s

# time /usr/bin/host.orig 208.73.175.193.combined.njabl.org
Host 208.73.175.193.combined.njabl.org not found: 3(NXDOMAIN)

real 0m12.009s
user 0m0.000s
sys 0m0.004s

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: bind9-host 1:9.8.1.dfsg.P1-4ubuntu0.22 [modified: usr/bin/host]
ProcVersionSignature: Ubuntu 3.2.0-120.163-virtual 3.2.79
Uname: Linux 3.2.0-120-virtual x86_64
ApportVersion: 2.0.1-0ubuntu17.15
Architecture: amd64
Date: Sat Apr 22 12:20:14 2017
InstallationMedia: Ubuntu-Server 10.04 LTS "Lucid Lynx" - Release amd64 (20100427)
MarkForUpload: True
SourcePackage: bind9
UpgradeStatus: Upgraded to precise on 2012-06-11 (1775 days ago)

[Christian Ehrhardt  (paelzer)]

Hi Ralf,
sorry but the output of your shell wrapper is rather long.
Do I understand it right that "time /usr/bin/host 209.73.175.193.dnsbl.njabl.org" gives you a segfault at 100% of the tries? Before you said time to time, so should we loop over it to see if one out of many reproduces this?

If it has crashed with a segfault you should find them in /var/crash, and can report them with apport-collect to add them to this bug.

If you happen to know - Is this a new behavior due to an update?

I see that newer versions report "2(SERVFAIL)" while the precise version does (as in your post) "3(NXDOMAIN)"

Since only the first is slow I ran 1000 with the following loop but could not reproduce:
for i in $(seq 1 1000); do time /usr/bin/host 209.73.175.193.dnsbl.njabl.org; done

[Christian Ehrhardt  (paelzer)]

Thank you for your report and thereby your help on Ubuntu.
But for now I have to mark it incomplete until further info is provided.

[Launchpad Janitor (janitor)]

[Expired for bind9 (Ubuntu) because there has been no activity for 60 days.]