Commit c995ae22 authored by Vijay Subramanian's avatar Vijay Subramanian Committed by David S. Miller
Browse files

tcp: Change return value of tcp_rcv_established() 



tcp_rcv_established() returns only one value namely 0. We change the return
value to void (as suggested by David Miller).

After commit 0c24604b (tcp: implement RFC 5961 4.2), we no longer send RSTs in
response to SYNs. We can remove the check and processing on the return value of
tcp_rcv_established().

We also fix jtcp_rcv_established() in tcp_probe.c to match that of
tcp_rcv_established().

Signed-off-by: default avatarVijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cc8c6c1b

include/net/tcp.h

+2 −2
Original line number Original line Diff line number Diff line
@@ -371,7 +371,7 @@ extern void tcp_delack_timer_handler(struct sock *sk); 
extern int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg);

extern int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg);

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

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

				 const struct tcphdr *th, unsigned int len);

				 const struct tcphdr *th, unsigned int len);

extern int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,

extern void tcp_rcv_established(struct sock *sk, struct sk_buff *skb,

				const struct tcphdr *th, unsigned int len);

				const struct tcphdr *th, unsigned int len);

extern void tcp_rcv_space_adjust(struct sock *sk);

extern void tcp_rcv_space_adjust(struct sock *sk);

extern void tcp_cleanup_rbuf(struct sock *sk, int copied);

extern void tcp_cleanup_rbuf(struct sock *sk, int copied);

net/ipv4/tcp_input.c

+6 −7
Original line number Original line Diff line number Diff line
@@ -5049,7 +5049,7 @@ discard: 
 *	the rest is checked inline. Fast processing is turned on in

 *	the rest is checked inline. Fast processing is turned on in

 *	tcp_data_queue when everything is OK.

 *	tcp_data_queue when everything is OK.

 */

 */

int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,

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

			 const struct tcphdr *th, unsigned int len)

			 const struct tcphdr *th, unsigned int len)

{

{

	struct tcp_sock *tp = tcp_sk(sk);

	struct tcp_sock *tp = tcp_sk(sk);
@@ -5127,7 +5127,7 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb, 
				tcp_ack(sk, skb, 0);

				tcp_ack(sk, skb, 0);

				__kfree_skb(skb);

				__kfree_skb(skb);

				tcp_data_snd_check(sk);

				tcp_data_snd_check(sk);

				return 0;

				return;

			} else { /* Header too small */

			} else { /* Header too small */

				TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);

				TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);

				goto discard;

				goto discard;
@@ -5220,7 +5220,7 @@ no_ack: 
			if (eaten)

			if (eaten)

				kfree_skb_partial(skb, fragstolen);

				kfree_skb_partial(skb, fragstolen);

			sk->sk_data_ready(sk, 0);

			sk->sk_data_ready(sk, 0);

			return 0;

			return;

		}

		}

	}

	}
@@ -5236,7 +5236,7 @@ slow_path: 
	 */

	 */





	if (!tcp_validate_incoming(sk, skb, th, 1))

	if (!tcp_validate_incoming(sk, skb, th, 1))

		return 0;

		return;





step5:

step5:

	if (tcp_ack(sk, skb, FLAG_SLOWPATH | FLAG_UPDATE_TS_RECENT) < 0)

	if (tcp_ack(sk, skb, FLAG_SLOWPATH | FLAG_UPDATE_TS_RECENT) < 0)
@@ -5252,7 +5252,7 @@ step5: 




	tcp_data_snd_check(sk);

	tcp_data_snd_check(sk);

	tcp_ack_snd_check(sk);

	tcp_ack_snd_check(sk);

	return 0;

	return;





csum_error:

csum_error:

	TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS);

	TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS);
@@ -5260,7 +5260,6 @@ csum_error: 




discard:

discard:

	__kfree_skb(skb);

	__kfree_skb(skb);

	return 0;

}

}

EXPORT_SYMBOL(tcp_rcv_established);

EXPORT_SYMBOL(tcp_rcv_established);

net/ipv4/tcp_ipv4.c

+1 −4
Original line number Original line Diff line number Diff line
@@ -1799,10 +1799,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) 
				sk->sk_rx_dst = NULL;

				sk->sk_rx_dst = NULL;

			}

			}

		}

		}

		if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) {

		tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len);

			rsk = sk;

			goto reset;

		}

		return 0;

		return 0;

	}

	}

net/ipv4/tcp_probe.c

+2 −3
Original line number Original line Diff line number Diff line
@@ -122,7 +122,7 @@ static inline int tcp_probe_avail(void) 
 * Hook inserted to be called before each receive packet.

 * Hook inserted to be called before each receive packet.

 * Note: arguments must match tcp_rcv_established()!

 * Note: arguments must match tcp_rcv_established()!

 */

 */

static int jtcp_rcv_established(struct sock *sk, struct sk_buff *skb,

static void jtcp_rcv_established(struct sock *sk, struct sk_buff *skb,

				 const struct tcphdr *th, unsigned int len)

				 const struct tcphdr *th, unsigned int len)

{

{

	const struct tcp_sock *tp = tcp_sk(sk);

	const struct tcp_sock *tp = tcp_sk(sk);
@@ -172,7 +172,6 @@ static int jtcp_rcv_established(struct sock *sk, struct sk_buff *skb, 
	}

	}





	jprobe_return();

	jprobe_return();

	return 0;

}

}





static struct jprobe tcp_jprobe = {

static struct jprobe tcp_jprobe = {

net/ipv6/tcp_ipv6.c

+1 −2
Original line number Original line Diff line number Diff line
@@ -1360,8 +1360,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 
			}

			}

		}

		}





		if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len))

		tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len);

			goto reset;

		if (opt_skb)

		if (opt_skb)

			goto ipv6_pktoptions;

			goto ipv6_pktoptions;

		return 0;

		return 0;

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