net/mptcp/mptcp_ipv4.c
######################
>>> NOW, m -j32 iso_img , problem is located in mptcp_v4_do_rcv() in net/mptcp/mptcp_ipv4.c
>>> that is, inet_csk_search_req
######################
-------------------------------------------------------------------------test-1 result
net/ipv4/mptcp_output.c: 792: mptcp_write_xmit
net/ipv4/tcp_output.c: 2558: __tcp_push_pending_frames
net/ipv4/tcp_ipv4.c: 1535: tcp_v4_do_rcv
net/mptcp/mptcp_ipv4.c: 191: mptcp_v4_do_rcv
-------------------------------------------------------------------------test-2 result
net/mptcp/mptcp_input.c: 1179: mptcp_find_join
net/mptcp/mptcp_input.c: 1201: mptcp_lookup_join
net/mptcp/mptcp_input.c: 1219: mptcp_lookup_join
net/mptcp/mptcp_input.c: 1241: mptcp_lookup_join
net/mptcp/mptcp_input.c: 1254: mptcp_lookup_join
net/ipv4/tcp_ipv4.c: 1917: tcp_v4_rcv
net/ipv4/tcp_ipv4.c: 1535: tcp_v4_do_rcv
net/mptcp/mptcp_ipv4.c: 191: mptcp_v4_do_rcv
-------------------------------------------------------------------------problem is located
unable to handle kernel NULL pointer dereference at 0000000000000048
IP: [<ffffffff81577fa2>] inet_csk_search_req+0x2f/0xad