CONFIG_IP_NF_CONNTRACK (not configurable)

modulename: ip_conntrack.ko

configname: CONFIG_IP_NF_CONNTRACK

Linux Kernel Configuration
└─>Networking
└─>Networking options
└─>Network packet filtering framework (Netfilter)
└─>Core Netfilter Configuration
└─>IP_NF_CONNTRACK
In linux kernel since version 2.6.12  
source code: