Zabbix Agent 3.2.10 Crashes

[zdsimpso]

I am running Zabbix-agent 3.2.10. I've compiled the zbx_unifi_Zabbix_3_2/unifi.c without error and the Zabbix agent loads it.

I can pull the unifi.alive value without issue, but the agent crashes when I try to pull a unifi.proxy value.
zabbix_agentd -t "unifi.alive"
unifi.alive [u|1]

zabbix_agentd -t "unifi.proxy[discovery,wlan]"
zabbix_agentd [18571]: ERROR: Got signal [signal:11(SIGSEGV),reason:1,refaddr:(nil)]. Crashing ...
zabbix_agentd [18571]: ERROR: ====== Fatal information: ======
zabbix_agentd [18571]: ERROR: Program counter: (nil)

<OUTPUT TRUNCATED>

zabbix_agentd [18571]: ERROR: ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
zabbix_agentd [18571]: ERROR: ================================
zabbix_agentd [18571]: ERROR: Please consider attaching a disassembly listing to your bug report.
zabbix_agentd [18571]: ERROR: This listing can be produced with, e.g., objdump -DSswx zabbix_agentd.
zabbix_agentd [18571]: ERROR: ================================

[zbx-sadman]

What OS you use?

[zdsimpso]

I'm on Debian 9.3

[zbx-sadman]

Ough... I still sit on Wheezy and test all on this release.

I'll try to install latest Debian on virtual machine when i will have some free time.

[zbx-sadman]

I've see no problem:

root@debian9:/usr/local/lib/zabbix# zabbix_agentd -t "unifi.alive"
unifi.alive                                   [u|1]

root@debian9:/usr/local/lib/zabbix# zabbix_agentd -t "unifi.proxy[discovery,wlan]"
unifi.proxy[discovery,wlan]                   [s|{"data":[{"{#SITENAME}":"default",  ...
"{#ISGUEST}":"1","{#ID}":"56a070ad9932e99b10769b7d","{#SITEDESC}":"South"}]}]

root@debian9:/usr/local/lib/zabbix# uname -a
Linux debian9 4.9.0-4-amd64 #1 SMP Debian 4.9.65-3 (2017-12-03) x86_64 GNU/Linux

root@debian9:/usr/local/sbin# zabbix_agentd -V
zabbix_agentd (daemon) (Zabbix) 3.2.10
Revision 74337 7 November 2017, compilation time: Dec 14 2017 04:52:52

Copyright (C) 2017 Zabbix SIA

[zdsimpso]

Herm. I just created a new stretch system, with base utils and ssh-server, and it's still crashing on me.

added the Zabbix 3.2 repo package
apt-get install zabbix-agent unzip
apt-get install build-essential
apt-get source zabbix-agent
cd /tmp
unzip unifi_proxy-master.zip
cd /zabbix-3.2.10
./configure
cd src/modules
cp -R /tmp/unifi_proxy-master/src/modules/zbx_unifi_Zabbix_3_2 ./unifi
cd unifi
make
mkdir -p /usr/lib/zabbix/modules/
cp unifi.so /usr/lib/zabbix/modules
cp /tmp/unifi_proxy-master/usr/local/lib/zabbix/unifi.conf /usr/lib/zabbix/modules
chown zabbix:zabbix /usr/lib/zabbix/modules/*
cp /tmp/unifi_proxy-master/etc/zabbix/zbx_unifi.conf /etc/zabbix/zabbix_agentd.d/
vim /etc/zabbix/zabbix_agentd.d/zbx_unifi.conf
<<Update module path to /usr/lib/zabbix/modules>>
vim /usr/lib/zabbix/modules/unifi.conf
<>
/etc/init.d/zabbix-agent restart

cd /tmp/unifi_proxy-master/src
gcc unifi_proxy_get.c -o unifi_proxy_get
./unifi_proxy_get 10.0.5.16 8448 "discovery,uap"
{"data":[{"{#SITEDESC}":
<>

zabbix_agentd -t "unifi.alive"
unifi.alive [u|1]

zabbix_agentd -t "unifi.proxy[discovery,wlan]"
zabbix_agentd [19761]: ERROR: Got signal [signal:11(SIGSEGV),reason:1,refaddr:(nil)]. Crashing ...
zabbix_agentd [19761]: ERROR: ====== Fatal information: ======
zabbix_agentd [19761]: ERROR: Program counter: (nil)
zabbix_agentd [19761]: ERROR: === Registers: ===
<>

[zbx-sadman]

May be something going wrong when precompiled agent package is used...

I just download as always full sources from Zabbix site (not from repo), compile agent only and install it. All other steps are close to yours.

I see that you make discovery for UAPs via CLI utility, but trying discover WLANs via zabbix_agentd .

[zbx-sadman]

I've found that precompiled agent crashing when zbx_tcp_connect() called by my module. On agentd which compiled from sources no this problem seen.

At this time i can't understand what is wrong.

[zbx-sadman]

So, the result of my investigation: i need to rewrite module code to make it more independent of Zabbix internal functions, because in https://support.zabbix.com/browse/ZBX-12900 (similar case) i've found the answer of Zabbix developers: "In your code you are using Zabbix functions, their behaviour may change without any prior notice. Closing as Won't Fix."

May be i'll done it in a week. Workaround is self-compiled agent.

[zbx-sadman]

@zdsimpso , you can try updated loadable module - i rewrited and tested via zabbix_agentd -t following:

• module for Zabbix 2.x;
• module for Zabbix >=3.2.x

At this time i haven't Zabbix 3.0/3.1 releases in my system and i leave corresponding code unchanged.

[zdsimpso]

Thanks!!

3.2.10 module appears to be working just fine now.

Tried it out on my 3.4.4 system and it appears to be working there as well.