mptcp: better msk-level shutdown.

Instead of re-implementing most of inet_shutdown, re-use
such helper, and implement the MPTCP-specific bits at the
'proto' level.

The msk-level disconnect() can now be invoked, lets provide a
suitable implementation.

As a side effect, this fixes bad state management for listener
sockets. The latter could lead to division by 0 oops since
commit ea4ca586b1 ("mptcp: refine MPTCP-level ack scheduling").

Fixes: 43b54c6ee3 ("mptcp: Use full MPTCP-level disconnect state machine")
Fixes: ea4ca586b1 ("mptcp: refine MPTCP-level ack scheduling")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paolo Abeni 2021-01-12 18:25:24 +01:00 committed by Jakub Kicinski
parent 20bc80b6f5
commit 76e2a55d16

View File

@ -2642,11 +2642,12 @@ static void mptcp_copy_inaddrs(struct sock *msk, const struct sock *ssk)
static int mptcp_disconnect(struct sock *sk, int flags)
{
/* Should never be called.
* inet_stream_connect() calls ->disconnect, but that
* refers to the subflow socket, not the mptcp one.
*/
WARN_ON_ONCE(1);
struct mptcp_subflow_context *subflow;
struct mptcp_sock *msk = mptcp_sk(sk);
__mptcp_flush_join_list(msk);
mptcp_for_each_subflow(msk, subflow)
tcp_disconnect(mptcp_subflow_tcp_sock(subflow), flags);
return 0;
}
@ -3089,6 +3090,14 @@ bool mptcp_finish_join(struct sock *ssk)
return true;
}
static void mptcp_shutdown(struct sock *sk, int how)
{
pr_debug("sk=%p, how=%d", sk, how);
if ((how & SEND_SHUTDOWN) && mptcp_close_state(sk))
__mptcp_wr_shutdown(sk);
}
static struct proto mptcp_prot = {
.name = "MPTCP",
.owner = THIS_MODULE,
@ -3098,7 +3107,7 @@ static struct proto mptcp_prot = {
.accept = mptcp_accept,
.setsockopt = mptcp_setsockopt,
.getsockopt = mptcp_getsockopt,
.shutdown = tcp_shutdown,
.shutdown = mptcp_shutdown,
.destroy = mptcp_destroy,
.sendmsg = mptcp_sendmsg,
.recvmsg = mptcp_recvmsg,
@ -3344,43 +3353,6 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock,
return mask;
}
static int mptcp_shutdown(struct socket *sock, int how)
{
struct mptcp_sock *msk = mptcp_sk(sock->sk);
struct sock *sk = sock->sk;
int ret = 0;
pr_debug("sk=%p, how=%d", msk, how);
lock_sock(sk);
how++;
if ((how & ~SHUTDOWN_MASK) || !how) {
ret = -EINVAL;
goto out_unlock;
}
if (sock->state == SS_CONNECTING) {
if ((1 << sk->sk_state) &
(TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
sock->state = SS_DISCONNECTING;
else
sock->state = SS_CONNECTED;
}
sk->sk_shutdown |= how;
if ((how & SEND_SHUTDOWN) && mptcp_close_state(sk))
__mptcp_wr_shutdown(sk);
/* Wake up anyone sleeping in poll. */
sk->sk_state_change(sk);
out_unlock:
release_sock(sk);
return ret;
}
static const struct proto_ops mptcp_stream_ops = {
.family = PF_INET,
.owner = THIS_MODULE,
@ -3394,7 +3366,7 @@ static const struct proto_ops mptcp_stream_ops = {
.ioctl = inet_ioctl,
.gettstamp = sock_gettstamp,
.listen = mptcp_listen,
.shutdown = mptcp_shutdown,
.shutdown = inet_shutdown,
.setsockopt = sock_common_setsockopt,
.getsockopt = sock_common_getsockopt,
.sendmsg = inet_sendmsg,
@ -3444,7 +3416,7 @@ static const struct proto_ops mptcp_v6_stream_ops = {
.ioctl = inet6_ioctl,
.gettstamp = sock_gettstamp,
.listen = mptcp_listen,
.shutdown = mptcp_shutdown,
.shutdown = inet_shutdown,
.setsockopt = sock_common_setsockopt,
.getsockopt = sock_common_getsockopt,
.sendmsg = inet6_sendmsg,