diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2022-05-04 14:54:07 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-05-05 19:00:15 -0700 |
| commit | f3589be0c420a3137e5902d15705ced6a36f3f43 (patch) | |
| tree | 979fd53649b562923da3d0f70013f98948c62b0f /net/mptcp/protocol.c | |
| parent | ea66758c1795cef81dc59cd5240e9d0f5c5207cf (diff) | |
mptcp: never shrink offered window
As per RFC, the offered MPTCP-level window should never shrink.
While we currently track the right edge, we don't enforce the
above constraint on the wire.
Additionally, concurrent xmit on different subflows can end-up in
erroneous right edge update.
Address the above explicitly updating the announced window and
protecting the update with an additional atomic operation (sic)
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/protocol.c')
| -rw-r--r-- | net/mptcp/protocol.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 961c2aba2a11..9e46cc89a8f7 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -216,7 +216,7 @@ static void mptcp_data_queue_ofo(struct mptcp_sock *msk, struct sk_buff *skb) seq = MPTCP_SKB_CB(skb)->map_seq; end_seq = MPTCP_SKB_CB(skb)->end_seq; - max_seq = READ_ONCE(msk->rcv_wnd_sent); + max_seq = atomic64_read(&msk->rcv_wnd_sent); pr_debug("msk=%p seq=%llx limit=%llx empty=%d", msk, seq, max_seq, RB_EMPTY_ROOT(&msk->out_of_order_queue)); @@ -225,7 +225,7 @@ static void mptcp_data_queue_ofo(struct mptcp_sock *msk, struct sk_buff *skb) mptcp_drop(sk, skb); pr_debug("oow by %lld, rcv_wnd_sent %llu\n", (unsigned long long)end_seq - (unsigned long)max_seq, - (unsigned long long)msk->rcv_wnd_sent); + (unsigned long long)atomic64_read(&msk->rcv_wnd_sent)); MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_NODSSWINDOW); return; } @@ -3004,7 +3004,7 @@ struct sock *mptcp_sk_clone(const struct sock *sk, mptcp_crypto_key_sha(msk->remote_key, NULL, &ack_seq); ack_seq++; WRITE_ONCE(msk->ack_seq, ack_seq); - WRITE_ONCE(msk->rcv_wnd_sent, ack_seq); + atomic64_set(&msk->rcv_wnd_sent, ack_seq); } sock_reset_flag(nsk, SOCK_RCU_FREE); @@ -3297,9 +3297,9 @@ 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->ack_seq, ack_seq); - WRITE_ONCE(msk->rcv_wnd_sent, ack_seq); WRITE_ONCE(msk->can_ack, 1); WRITE_ONCE(msk->snd_una, msk->write_seq); + atomic64_set(&msk->rcv_wnd_sent, ack_seq); mptcp_pm_new_connection(msk, ssk, 0); |