Packet marking using secmarks for netfilter

configname: CONFIG_SECURITY_SMACK_NETFILTER

Linux Kernel Configuration
└─>Security options
└─>Packet marking using secmarks for netfilter
In linux kernel since version 4 (release Date: 2015-04-12)  
This enables security marking of network packets using
Smack labels.
If you are unsure how to answer this question, answer N.