CONFIG_IP_MROUTE_COMMON (not configurable)

modulename: ipmr_base.ko

configname: CONFIG_IP_MROUTE_COMMON

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>IP_MROUTE_COMMON
In linux kernel since version 4.2 (release Date: 2015-08-30)  
source code:
net/ipv4/ipmr_base.c