netdev - [PATCH net-next 4/4] mptcp: poll allow write call before actual connect

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220926232739.76317-5-mathew.j.martineau@linux.intel.com>
Date:   Mon, 26 Sep 2022 16:27:39 -0700
From:   Mat Martineau <mathew.j.martineau@...ux.intel.com>
To:     netdev@...r.kernel.org
Cc:     Benjamin Hesmans <benjamin.hesmans@...sares.net>,
        davem@...emloft.net, kuba@...nel.org, pabeni@...hat.com,
        edumazet@...gle.com, dmytro@...tyi.net,
        matthieu.baerts@...sares.net, mptcp@...ts.linux.dev,
        Mat Martineau <mathew.j.martineau@...ux.intel.com>
Subject: [PATCH net-next 4/4] mptcp: poll allow write call before actual connect

From: Benjamin Hesmans <benjamin.hesmans@...sares.net>

If fastopen is used, poll must allow a first write that will trigger
the SYN+data

Similar to what is done in tcp_poll().

Acked-by: Paolo Abeni <pabeni@...hat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@...sares.net>
Signed-off-by: Benjamin Hesmans <benjamin.hesmans@...sares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@...ux.intel.com>
---
 net/mptcp/protocol.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index fc753896caa0..16c3a6fc347f 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -3548,6 +3548,7 @@ static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 
 do_connect:
 	err = ssock->ops->connect(ssock, uaddr, addr_len, flags);
+	inet_sk(sock->sk)->defer_connect = inet_sk(ssock->sk)->defer_connect;
 	sock->state = ssock->state;
 
 	/* on successful connect, the msk state will be moved to established by
@@ -3698,6 +3699,9 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock,
 	if (state != TCP_SYN_SENT && state != TCP_SYN_RECV) {
 		mask |= mptcp_check_readable(msk);
 		mask |= mptcp_check_writeable(msk);
+	} else if (state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) {
+		/* cf tcp_poll() note about TFO */
+		mask |= EPOLLOUT | EPOLLWRNORM;
 	}
 	if (sk->sk_shutdown == SHUTDOWN_MASK || state == TCP_CLOSE)
 		mask |= EPOLLHUP;
-- 
2.37.3