Regression fix in check_smart monitoring plugin 6.18.2

Written by - 0 comments

Published on - Listed in Monitoring Hardware Icinga Nagios


A new version of check_smart, a monitoring plugin to monitor hard drives (HDD), solid state drives (SSD) and NVMe drives, is available.

The newest release, 6.18.2, is a bugfix release and fixes a regression previously introduced in 6.18.1.

In version 6.18.1, a security release, the handling of symbolic links was adjusted. It could have been possible (before 6.18.1) to create a symlink to a malicious file and abuse as command injection. Following this, symlinks have been disabled. 

But this created a problem for users that used the /dev/disk/ directory as device path. As you might be aware, /dev/disk/ subdirectories contain symbolic links to the relevant block device. For example:

$ ./check_smart.pl -i ata -d /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX --debug
(debug) Found /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX
(debug) /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX is a symlink, skipping for security reasons
Could not find any valid block/character special device for device /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX  !

The regression fix is in the latest release 6.18.2, available from today. It allows to use symlinks but also verifies that the real path behind the symlink is an actual block device/drive.

$ ./check_smart.pl -i ata -d /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX --debug
(debug) Found /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX
(debug) /dev/disk/by-id/ata-Samsung_SSD_850_EVO_500GB_XXXXXXXXXXXXXXXX is a symlink to block device /dev/sdb, using resolved path
###########################################################
(debug) CHECK 1: getting overall SMART health status for /dev/sdb 
########################################################### 
[...]

In order to do that, the Perl module Cwd needs to be loaded additionally. As this is part of the Perl standard library, I'm fairly certain that it won't break compatibility and won't require additional requirements.

The regression was reported by Simon F, thanks a lot for the collaboration!


Add a comment

Show form to leave a comment

Comments (newest first)

No comments yet.

RSS feed

Blog Tags:

  AWS   Android   Ansible   Apache   Apple   Atlassian   BSD   Backup   Bash   Bluecoat   CMS   Chef   Cloud   Coding   Consul   Containers   CouchDB   DB   DNS   Databases   Docker   ELK   Elasticsearch   Filebeat   FreeBSD   Galera   Git   GlusterFS   Grafana   Graphics   HAProxy   HTML   Hacks   Hardware   Icinga   Influx   Internet   Java   KVM   Kibana   Kodi   Kubernetes   LVM   LXC   Linux   Logstash   Mac   Macintosh   Mail   MariaDB   Minio   MongoDB   Monitoring   Multimedia   MySQL   NFS   Nagios   Network   Nginx   OSSEC   OTRS   Observability   Office   OpenSearch   PHP   Perl   Personal   PostgreSQL   PowerDNS   Proxmox   Proxy   Python   Rancher   Rant   Redis   Roundcube   SSL   Samba   Seafile   Security   Shell   SmartOS   Solaris   Surveillance   Systemd   TLS   Tomcat   Ubuntu   Unix   VMware   Varnish   Virtualization   Windows   Wireless   Wordpress   Wyse   ZFS   Znuny   Zoneminder