diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2020-05-29 17:43:29 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-05-30 21:39:13 -0700 |
| commit | 41be81a8d3d09acb9033799938306349328861f9 (patch) | |
| tree | 20cb78f94610de7a0a694a4f87436d9db51a5f9b | |
| parent | 05aa69e5cba61d8900970a364825f854401694ec (diff) | |
mptcp: fix unblocking connect()
Currently unblocking connect() on MPTCP sockets fails frequently.
If mptcp_stream_connect() is invoked to complete a previously
attempted unblocking connection, it will still try to create
the first subflow via __mptcp_socket_create(). If the 3whs is
completed and the 'can_ack' flag is already set, the latter
will fail with -EINVAL.
This change addresses the issue checking for pending connect and
delegating the completion to the first subflow. Additionally
do msk addresses and sk_state changes only when needed.
Fixes: 2303f994b3e1 ("mptcp: Associate MPTCP context with TCP socket")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/mptcp/protocol.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index c8675d2eb5b9..8959a74f707d 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1712,6 +1712,14 @@ static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr, int err; lock_sock(sock->sk); + if (sock->state != SS_UNCONNECTED && msk->subflow) { + /* pending connection or invalid state, let existing subflow + * cope with that + */ + ssock = msk->subflow; + goto do_connect; + } + ssock = __mptcp_socket_create(msk, TCP_SYN_SENT); if (IS_ERR(ssock)) { err = PTR_ERR(ssock); @@ -1726,9 +1734,17 @@ static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr, mptcp_subflow_ctx(ssock->sk)->request_mptcp = 0; #endif +do_connect: err = ssock->ops->connect(ssock, uaddr, addr_len, flags); - inet_sk_state_store(sock->sk, inet_sk_state_load(ssock->sk)); - mptcp_copy_inaddrs(sock->sk, ssock->sk); + sock->state = ssock->state; + + /* on successful connect, the msk state will be moved to established by + * subflow_finish_connect() + */ + if (!err || err == EINPROGRESS) + mptcp_copy_inaddrs(sock->sk, ssock->sk); + else + inet_sk_state_store(sock->sk, inet_sk_state_load(ssock->sk)); unlock: release_sock(sock->sk); |