microsoft
/
WSL2-Linux-Kernel
зеркало из https://github.com/microsoft/WSL2-Linux-Kernel.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность

mptcp: consolidate fallback and non fallback state machine 

commit 81c1d02901 upstream.

An orphaned msk releases the used resources via the worker,
when the latter first see the msk in CLOSED status.

If the msk status transitions to TCP_CLOSE in the release callback
invoked by the worker's final release_sock(), such instance of the
workqueue will not take any action.

Additionally the MPTCP code prevents scheduling the worker once the
socket reaches the CLOSE status: such msk resources will be leaked.

The only code path that can trigger the above scenario is the
__mptcp_check_send_data_fin() in fallback mode.

Address the issue removing the special handling of fallback socket
in __mptcp_check_send_data_fin(), consolidating the state machine
for fallback and non fallback socket.

Since non-fallback sockets do not send and do not receive data_fin,
the mptcp code can update the msk internal status to match the next
step in the SM every time data fin (ack) should be generated or
received.

As a consequence we can remove a bunch of checks for fallback from
the fastpath.

Fixes: 6e628cd3a8 ("mptcp: use mptcp release_cb for delayed tasks")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Paolo Abeni 2023-06-20 18:24:21 +02:00 коммит произвёл Greg Kroah-Hartman
Родитель 42ff95b4bd
Коммит b46021ab83
2 изменённых файлов: 25 добавлений и 31 удалений
Показать статистику Скачать Patch файл Скачать Diff файл Показать все файлы Свернуть все файлы

37
net/mptcp/protocol.c
Просмотреть файл

@ -51,7 +51,7 @@ enum {
static struct percpu_counter mptcp_sockets_allocated;
static void __mptcp_destroy_sock(struct sock *sk);
static void __mptcp_check_send_data_fin(struct sock *sk);
static void mptcp_check_send_data_fin(struct sock *sk);
DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
static struct net_device mptcp_napi_dev;
@ -355,8 +355,7 @@ static bool mptcp_pending_data_fin_ack(struct sock *sk)
{
struct mptcp_sock *msk = mptcp_sk(sk);
return !__mptcp_check_fallback(msk) &&
((1 << sk->sk_state) &
return ((1 << sk->sk_state) &
(TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_LAST_ACK)) &&
msk->write_seq == READ_ONCE(msk->snd_una);
}
@ -509,9 +508,6 @@ static bool mptcp_check_data_fin(struct sock *sk)
u64 rcv_data_fin_seq;
bool ret = false;
if (__mptcp_check_fallback(msk))
return ret;
/* Need to ack a DATA_FIN received from a peer while this side
* of the connection is in ESTABLISHED, FIN_WAIT1, or FIN_WAIT2.
* msk->rcv_data_fin was set when parsing the incoming options
@ -549,6 +545,7 @@ static bool mptcp_check_data_fin(struct sock *sk)
}
ret = true;
if (!__mptcp_check_fallback(msk))
mptcp_send_ack(msk);
mptcp_close_wake_up(sk);
}
@ -1612,7 +1609,7 @@ out:
if (!mptcp_timer_pending(sk))
mptcp_reset_timer(sk);
if (copied)
__mptcp_check_send_data_fin(sk);
mptcp_check_send_data_fin(sk);
}
static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk)
@ -2451,7 +2448,6 @@ static void mptcp_worker(struct work_struct *work)
if (unlikely((1 << state) & (TCPF_CLOSE | TCPF_LISTEN)))
goto unlock;
mptcp_check_data_fin_ack(sk);
mptcp_flush_join_list(msk);
mptcp_check_fastclose(msk);
@ -2462,7 +2458,8 @@ static void mptcp_worker(struct work_struct *work)
if (test_and_clear_bit(MPTCP_WORK_EOF, &msk->flags))
mptcp_check_for_eof(msk);
__mptcp_check_send_data_fin(sk);
mptcp_check_send_data_fin(sk);
mptcp_check_data_fin_ack(sk);
mptcp_check_data_fin(sk);
/* There is no point in keeping around an orphaned sk timedout or
@ -2591,6 +2588,12 @@ void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how)
pr_debug("Fallback");
ssk->sk_shutdown |= how;
tcp_shutdown(ssk, how);
/* simulate the data_fin ack reception to let the state
* machine move forward
*/
WRITE_ONCE(mptcp_sk(sk)->snd_una, mptcp_sk(sk)->snd_nxt);
mptcp_schedule_work(sk);
} else {
pr_debug("Sending DATA_FIN on subflow %p", ssk);
tcp_send_ack(ssk);
@ -2630,7 +2633,7 @@ static int mptcp_close_state(struct sock *sk)
return next & TCP_ACTION_FIN;
}
static void __mptcp_check_send_data_fin(struct sock *sk)
static void mptcp_check_send_data_fin(struct sock *sk)
{
struct mptcp_subflow_context *subflow;
struct mptcp_sock *msk = mptcp_sk(sk);
@ -2648,18 +2651,6 @@ static void __mptcp_check_send_data_fin(struct sock *sk)
WRITE_ONCE(msk->snd_nxt, msk->write_seq);
/* fallback socket will not get data_fin/ack, can move to the next
* state now
*/
if (__mptcp_check_fallback(msk)) {
if ((1 << sk->sk_state) & (TCPF_CLOSING | TCPF_LAST_ACK)) {
inet_sk_state_store(sk, TCP_CLOSE);
mptcp_close_wake_up(sk);
} else if (sk->sk_state == TCP_FIN_WAIT1) {
inet_sk_state_store(sk, TCP_FIN_WAIT2);
}
}
mptcp_flush_join_list(msk);
mptcp_for_each_subflow(msk, subflow) {
struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow);
@ -2680,7 +2671,7 @@ static void __mptcp_wr_shutdown(struct sock *sk)
WRITE_ONCE(msk->write_seq, msk->write_seq + 1);
WRITE_ONCE(msk->snd_data_fin_enable, 1);
__mptcp_check_send_data_fin(sk);
mptcp_check_send_data_fin(sk);
}
static void __mptcp_destroy_sock(struct sock *sk)

17
net/mptcp/subflow.c
Просмотреть файл

@ -1653,14 +1653,16 @@ static void subflow_state_change(struct sock *sk)
{
struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
struct sock *parent = subflow->conn;
struct mptcp_sock *msk;
__subflow_state_change(sk);
msk = mptcp_sk(parent);
if (subflow_simultaneous_connect(sk)) {
mptcp_propagate_sndbuf(parent, sk);
mptcp_do_fallback(sk);
mptcp_rcv_space_init(mptcp_sk(parent), sk);
pr_fallback(mptcp_sk(parent));
mptcp_rcv_space_init(msk, sk);
pr_fallback(msk);
subflow->conn_finished = 1;
mptcp_set_connected(parent);
}
@ -1676,11 +1678,12 @@ static void subflow_state_change(struct sock *sk)
subflow_sched_work_if_closed(mptcp_sk(parent), sk);
if (__mptcp_check_fallback(mptcp_sk(parent)) &&
!subflow->rx_eof && subflow_is_done(sk)) {
subflow->rx_eof = 1;
mptcp_subflow_eof(parent);
}
/* when the fallback subflow closes the rx side, trigger a 'dummy'
* ingress data fin, so that the msk state will follow along
*/
if (__mptcp_check_fallback(msk) && subflow_is_done(sk) && msk->first == sk &&
mptcp_update_rcv_data_fin(msk, READ_ONCE(msk->ack_seq), true))
mptcp_schedule_work(parent);
}
static int subflow_ulp_init(struct sock *sk)