Hi, Thank you for the patch! Yet something to improve: [auto build test ERROR on mptcp/export] [also build test ERROR on next-20210624] [cannot apply to kselftest/next linus/master v5.13-rc7] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/wujianguo106-163-com/Fix-some-mptcp-syncookie-process-bugs/20210625-110557 base: https://github.com/multipath-tcp/mptcp_net-next.git export config: i386-randconfig-a011-20210622 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/8bac278b64d6949fede4d0f383ca5f01fca11ef7 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review wujianguo106-163-com/Fix-some-mptcp-syncookie-process-bugs/20210625-110557 git checkout 8bac278b64d6949fede4d0f383ca5f01fca11ef7 # save the attached .config to linux build tree make W=1 ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): net/ipv4/tcp_input.c: In function 'tcp_data_queue': >> net/ipv4/tcp_input.c:4950:25: error: invalid use of void expression 4950 | if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) { | ^ net/ipv4/tcp_input.c: In function 'tcp_rcv_state_process': net/ipv4/tcp_input.c:6537:27: error: invalid use of void expression 6537 | if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) | ^ vim +4950 net/ipv4/tcp_input.c 4940 4941 static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) 4942 { 4943 struct tcp_sock *tp = tcp_sk(sk); 4944 bool fragstolen; 4945 int eaten; 4946 4947 /* If a subflow has been reset, the packet should not continue 4948 * to be processed, drop the packet. 4949 */ > 4950 if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) { 4951 __kfree_skb(skb); 4952 return; 4953 } 4954 4955 if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) { 4956 __kfree_skb(skb); 4957 return; 4958 } 4959 skb_dst_drop(skb); 4960 __skb_pull(skb, tcp_hdr(skb)->doff * 4); 4961 4962 tp->rx_opt.dsack = 0; 4963 4964 /* Queue data for delivery to the user. 4965 * Packets in sequence go to the receive queue. 4966 * Out of sequence packets to the out_of_order_queue. 4967 */ 4968 if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) { 4969 if (tcp_receive_window(tp) == 0) { 4970 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); 4971 goto out_of_window; 4972 } 4973 4974 /* Ok. In sequence. In window. */ 4975 queue_and_out: 4976 if (skb_queue_len(&sk->sk_receive_queue) == 0) 4977 sk_forced_mem_schedule(sk, skb->truesize); 4978 else if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) { 4979 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP); 4980 sk->sk_data_ready(sk); 4981 goto drop; 4982 } 4983 4984 eaten = tcp_queue_rcv(sk, skb, &fragstolen); 4985 if (skb->len) 4986 tcp_event_data_recv(sk, skb); 4987 if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) 4988 tcp_fin(sk); 4989 4990 if (!RB_EMPTY_ROOT(&tp->out_of_order_queue)) { 4991 tcp_ofo_queue(sk); 4992 4993 /* RFC5681. 4.2. SHOULD send immediate ACK, when 4994 * gap in queue is filled. 4995 */ 4996 if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) 4997 inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW; 4998 } 4999 5000 if (tp->rx_opt.num_sacks) 5001 tcp_sack_remove(tp); 5002 5003 tcp_fast_path_check(sk); 5004 5005 if (eaten > 0) 5006 kfree_skb_partial(skb, fragstolen); 5007 if (!sock_flag(sk, SOCK_DEAD)) 5008 tcp_data_ready(sk); 5009 return; 5010 } 5011 5012 if (!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) { 5013 tcp_rcv_spurious_retrans(sk, skb); 5014 /* A retransmit, 2nd most common case. Force an immediate ack. */ 5015 NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST); 5016 tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq); 5017 5018 out_of_window: 5019 tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); 5020 inet_csk_schedule_ack(sk); 5021 drop: 5022 tcp_drop(sk, skb); 5023 return; 5024 } 5025 5026 /* Out of window. F.e. zero window probe. */ 5027 if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt + tcp_receive_window(tp))) 5028 goto out_of_window; 5029 5030 if (before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { 5031 /* Partial packet, seq < rcv_next < end_seq */ 5032 tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, tp->rcv_nxt); 5033 5034 /* If window is closed, drop tail of packet. But after 5035 * remembering D-SACK for its head made in previous line. 5036 */ 5037 if (!tcp_receive_window(tp)) { 5038 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); 5039 goto out_of_window; 5040 } 5041 goto queue_and_out; 5042 } 5043 5044 tcp_data_queue_ofo(sk, skb); 5045 } 5046 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org