Commit 7d6ed9af authored by Jason Xing's avatar Jason Xing Committed by David S. Miller
Browse files

tcp: add dropreasons in tcp_rcv_state_process() 



In this patch, I equipped this function with more dropreasons, but
it still doesn't work yet, which I will do later.

Signed-off-by: default avatarJason Xing <kernelxing@tencent.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Reviewed-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e615e3a2

include/net/tcp.h

+1 −1
Original line number Diff line number Diff line
@@ -348,7 +348,7 @@ void tcp_wfree(struct sk_buff *skb); 
void tcp_write_timer_handler(struct sock *sk);

void tcp_delack_timer_handler(struct sock *sk);

int tcp_ioctl(struct sock *sk, int cmd, int *karg);

int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb);

enum skb_drop_reason tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb);

void tcp_rcv_established(struct sock *sk, struct sk_buff *skb);

void tcp_rcv_space_adjust(struct sock *sk);

int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp);

net/ipv4/tcp_input.c

+12 −7
Original line number Diff line number Diff line
@@ -6619,7 +6619,8 @@ static void tcp_rcv_synrecv_state_fastopen(struct sock *sk) 
 *	address independent.

 */



int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)

enum skb_drop_reason

tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)

{

	struct tcp_sock *tp = tcp_sk(sk);

	struct inet_connection_sock *icsk = inet_csk(sk);
@@ -6635,7 +6636,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 


	case TCP_LISTEN:

		if (th->ack)

			return 1;

			return SKB_DROP_REASON_TCP_FLAGS;



		if (th->rst) {

			SKB_DR_SET(reason, TCP_RESET);
@@ -6704,8 +6705,12 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 
				  FLAG_NO_CHALLENGE_ACK);



	if ((int)reason <= 0) {

		if (sk->sk_state == TCP_SYN_RECV)

			return 1;	/* send one RST */

		if (sk->sk_state == TCP_SYN_RECV) {

			/* send one RST */

			if (!reason)

				return SKB_DROP_REASON_TCP_OLD_ACK;

			return -reason;

		}

		/* accept old ack during closing */

		if ((int)reason < 0) {

			tcp_send_challenge_ack(sk);
@@ -6781,7 +6786,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 
		if (READ_ONCE(tp->linger2) < 0) {

			tcp_done(sk);

			NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);

			return 1;

			return SKB_DROP_REASON_TCP_ABORT_ON_DATA;

		}

		if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&

		    after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt)) {
@@ -6790,7 +6795,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 
				tcp_fastopen_active_disable(sk);

			tcp_done(sk);

			NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);

			return 1;

			return SKB_DROP_REASON_TCP_ABORT_ON_DATA;

		}



		tmo = tcp_fin_time(sk);
@@ -6855,7 +6860,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 
			    after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt)) {

				NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);

				tcp_reset(sk, skb);

				return 1;

				return SKB_DROP_REASON_TCP_ABORT_ON_DATA;

			}

		}

		fallthrough;