it maybe help you./usr/src/linux/net/ipv4/netfilter/ip_conntrack_proto_udp.c#define UDP_TIMEOUT (30*HZ)#define UDP_STREAM_TIMEOUT (180*HZ)To change these values you can set up the udp timeout values.
tcp
/usr/src/linux/net/ipv4/netfilter/ip_conntrack_proto_tcp.c:
static unsigned long tcp_timeouts[]= { 30 MINS, /* TCP_CONNTRACK_NONE, */5 DAYS, /* TCP_CONNTRACK_ESTABLISHED, */2 MINS, /* TCP_CONNTRACK_SYN_SENT, */60 SECS, /* TCP_CONNTRACK_SYN_RECV, */2 MINS, /* TCP_CONNTRACK_FIN_WAIT, */2 MINS, /* TCP_CONNTRACK_TIME_WAIT, */10 SECS, /* TCP_CONNTRACK_CLOSE, */60 SECS, /* TCP_CONNTRACK_CLOSE_WAIT, */30 SECS, /* TCP_CONNTRACK_LAST_ACK, */2 MINS, /* TCP_CONNTRACK_LISTEN, */};I only find these , but I am not sure whether it work.
