mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

mptcp: fix rcv space initialization 

mptcp_rcv_space_init() is supposed to happen under the msk socket
lock, but active msk socket does that without such protection.

Leverage the existing mptcp_propagate_state() helper to that extent.
We need to ensure mptcp_rcv_space_init will happen before
mptcp_rcv_space_adjust(), and the release_cb does not assure that:
explicitly check for such condition.

While at it, move the wnd_end initialization out of mptcp_rcv_space_init(),
it never belonged there.

Note that the race does not produce ill effect in practice, but
change allows cleaning-up and defying better the locking model.

Fixes: a6b118febb ("mptcp: add receive buffer auto-tuning")
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 (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Paolo Abeni 2024-02-08 19:03:50 +01:00 committed by David S. Miller
parent bdd70eb689
commit 013e3179db
3 changed files with 10 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
net/mptcp/protocol.c
View File

@ -1963,6 +1963,9 @@ static void mptcp_rcv_space_adjust(struct mptcp_sock *msk, int copied)
if (copied <= 0)
return;
if (!msk->rcvspace_init)
mptcp_rcv_space_init(msk, msk->first);
msk->rcvq_space.copied += copied;
mstamp = div_u64(tcp_clock_ns(), NSEC_PER_USEC);
@ -3160,6 +3163,7 @@ static int mptcp_disconnect(struct sock *sk, int flags)
msk->bytes_received = 0;
msk->bytes_sent = 0;
msk->bytes_retrans = 0;
msk->rcvspace_init = 0;
WRITE_ONCE(sk->sk_shutdown, 0);
sk_error_report(sk);
@ -3247,6 +3251,7 @@ void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk)
{
const struct tcp_sock *tp = tcp_sk(ssk);
msk->rcvspace_init = 1;
msk->rcvq_space.copied = 0;
msk->rcvq_space.rtt_us = 0;
@ -3257,8 +3262,6 @@ void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk)
TCP_INIT_CWND * tp->advmss);
if (msk->rcvq_space.space == 0)
msk->rcvq_space.space = TCP_INIT_CWND * TCP_MSS_DEFAULT;
WRITE_ONCE(msk->wnd_end, msk->snd_nxt + tcp_sk(ssk)->snd_wnd);
}
void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags)
@ -3478,10 +3481,9 @@ void mptcp_finish_connect(struct sock *ssk)
WRITE_ONCE(msk->write_seq, subflow->idsn + 1);
WRITE_ONCE(msk->snd_nxt, msk->write_seq);
WRITE_ONCE(msk->snd_una, msk->write_seq);
WRITE_ONCE(msk->wnd_end, msk->snd_nxt + tcp_sk(ssk)->snd_wnd);
mptcp_pm_new_connection(msk, ssk, 0);
mptcp_rcv_space_init(msk, ssk);
}
void mptcp_sock_graft(struct sock *sk, struct socket *parent)

3
net/mptcp/protocol.h
View File

@ -304,7 +304,8 @@ struct mptcp_sock {
nodelay:1,
fastopening:1,
in_accept_queue:1,
free_first:1;
free_first:1,
rcvspace_init:1;
struct work_struct work;
struct sk_buff *ooo_last_skb;
struct rb_root out_of_order_queue;

4
net/mptcp/subflow.c
View File

@ -424,6 +424,8 @@ void __mptcp_sync_state(struct sock *sk, int state)
struct mptcp_sock *msk = mptcp_sk(sk);
__mptcp_propagate_sndbuf(sk, msk->first);
if (!msk->rcvspace_init)
mptcp_rcv_space_init(msk, msk->first);
if (sk->sk_state == TCP_SYN_SENT) {
mptcp_set_state(sk, state);
sk->sk_state_change(sk);
@ -545,7 +547,6 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
}
} else if (mptcp_check_fallback(sk)) {
fallback:
mptcp_rcv_space_init(msk, sk);
mptcp_propagate_state(parent, sk);
}
return;
@ -1744,7 +1745,6 @@ static void subflow_state_change(struct sock *sk)
msk = mptcp_sk(parent);
if (subflow_simultaneous_connect(sk)) {
mptcp_do_fallback(sk);
mptcp_rcv_space_init(msk, sk);
pr_fallback(msk);
subflow->conn_finished = 1;
mptcp_propagate_state(parent, sk);