Created attachment 273405 [details] linux-4.4-netlink-genlmcgroup.patch Kernel Version: 4.4 File: netlink/genetlink.c While reserving multicast groups for a netlink family in the kernel, if the request has more than 13 groups the code allocates only 13 groups and returns success. In the function "genl_allocate_reserve_groups" the variable "id" is returned with the first available multicast group slot but it doesn't check if the request "n_groups" is more than 13. Attached patch fixes the problem.