Commit 74696496 authored by Litao Jiao's avatar Litao Jiao
Browse files

net/smc: align the connect behaviour with TCP 

mainline inclusion
from mainline-v5.19-rc1
commit 3aba1030
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6TK1U
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3aba103006bcc4a7472b7c9506b3bc065ffb7992



--------------------------------

Connect with O_NONBLOCK will not be completed immediately
and returns -EINPROGRESS. It is possible to use selector/poll
for completion by selecting the socket for writing. After select
indicates writability, a second connect function call will return
0 to indicate connected successfully as TCP does, but smc returns
-EISCONN. Use socket state for smc to indicate connect state, which
can help smc aligning the connect behaviour with TCP.

Signed-off-by: default avatarGuangguan Wang <guangguan.wang@linux.alibaba.com>
Acked-by: default avatarKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarLitao Jiao <jiaolitao@sangfor.com.cn>
parent 22bae0fc

net/smc/af_smc.c

+46 −4
Original line number Diff line number Diff line
@@ -1097,9 +1097,29 @@ static int smc_connect(struct socket *sock, struct sockaddr *addr, 
		goto out_err;



	lock_sock(sk);

	switch (sock->state) {

	default:

		rc = -EINVAL;

		goto out;

	case SS_CONNECTED:

		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;

		goto out;

	case SS_CONNECTING:

		if (sk->sk_state == SMC_ACTIVE)

			goto connected;

		break;

	case SS_UNCONNECTED:

		sock->state = SS_CONNECTING;

		break;

	}



	switch (sk->sk_state) {

	default:

		goto out;

	case SMC_CLOSED:

		rc = sock_error(sk) ? : -ECONNABORTED;

		sock->state = SS_UNCONNECTED;

		goto out;

	case SMC_ACTIVE:

		rc = -EISCONN;

		goto out;
@@ -1118,21 +1138,25 @@ static int smc_connect(struct socket *sock, struct sockaddr *addr, 
	if (rc && rc != -EINPROGRESS)

		goto out;



	if (smc->use_fallback)

	if (smc->use_fallback) {

		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;

		goto out;

	}

	sock_hold(&smc->sk); /* sock put in passive closing */

	if (flags & O_NONBLOCK) {

		if (queue_work(smc_hs_wq, &smc->connect_work))

			smc->connect_nonblock = 1;

		rc = -EINPROGRESS;

		goto out;

	} else {

		rc = __smc_connect(smc);

		if (rc < 0)

			goto out;

		else

			rc = 0; /* success cases including fallback */

	}



connected:

	rc = 0;

	sock->state = SS_CONNECTED;

out:

	release_sock(sk);

out_err:
@@ -1234,6 +1258,7 @@ struct sock *smc_accept_dequeue(struct sock *parent, 
		}

		if (new_sock) {

			sock_graft(new_sk, new_sock);

			new_sock->state = SS_CONNECTED;

			if (isk->use_fallback) {

				smc_sk(new_sk)->clcsock->file = new_sock->file;

				isk->clcsock->file->private_data = isk->clcsock;
@@ -1864,7 +1889,7 @@ static int smc_listen(struct socket *sock, int backlog) 


	rc = -EINVAL;

	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||

	    smc->connect_nonblock)

	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)

		goto out;



	rc = 0;
@@ -2134,6 +2159,17 @@ static int smc_shutdown(struct socket *sock, int how) 


	lock_sock(sk);



	if (sock->state == SS_CONNECTING) {

		if (sk->sk_state == SMC_ACTIVE)

			sock->state = SS_CONNECTED;

		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||

			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||

			 sk->sk_state == SMC_APPCLOSEWAIT1 ||

			 sk->sk_state == SMC_APPCLOSEWAIT2 ||

			 sk->sk_state == SMC_APPFINCLOSEWAIT)

			sock->state = SS_DISCONNECTING;

	}



	rc = -ENOTCONN;

	if ((sk->sk_state != SMC_ACTIVE) &&

	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
@@ -2147,6 +2183,7 @@ static int smc_shutdown(struct socket *sock, int how) 
		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;

		if (sk->sk_shutdown == SHUTDOWN_MASK) {

			sk->sk_state = SMC_CLOSED;

			sk->sk_socket->state = SS_UNCONNECTED;

			sock_put(sk);

		}

		goto out;
@@ -2172,6 +2209,10 @@ static int smc_shutdown(struct socket *sock, int how) 
	/* map sock_shutdown_cmd constants to sk_shutdown value range */

	sk->sk_shutdown |= how + 1;



	if (sk->sk_state == SMC_CLOSED)

		sock->state = SS_UNCONNECTED;

	else

		sock->state = SS_DISCONNECTING;

out:

	release_sock(sk);

	return rc ? rc : rc1;
@@ -2463,6 +2504,7 @@ static int smc_create(struct net *net, struct socket *sock, int protocol, 


	rc = -ENOBUFS;

	sock->ops = &smc_sock_ops;

	sock->state = SS_UNCONNECTED;

	sk = smc_sock_alloc(net, sock, protocol);

	if (!sk)

		goto out;