diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2021-02-19 18:35:40 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-02-23 03:54:59 +0100 |
| commit | 52557dbc7538ecceb27ef2206719a47a8039a335 (patch) | |
| tree | f408921b80f8f4659198c29569f578d99d153428 | |
| parent | mptcp: provide subflow aware release function (diff) | |
| download | linux-52557dbc7538ecceb27ef2206719a47a8039a335.tar.xz linux-52557dbc7538ecceb27ef2206719a47a8039a335.zip | |
mptcp: do not wakeup listener for MPJ subflows
MPJ subflows are not exposed as fds to user spaces. As such,
incoming MPJ subflows are removed from the accept queue by
tcp_check_req()/tcp_get_cookie_sock().
Later tcp_child_process() invokes subflow_data_ready() on the
parent socket regardless of the subflow kind, leading to poll
wakeups even if the later accept will block.
Address the issue by double-checking the queue state before
waking the user-space.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/164
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/mptcp/subflow.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 06e233410e0e..e1fbcab257e6 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1096,6 +1096,12 @@ static void subflow_data_ready(struct sock *sk) msk = mptcp_sk(parent); if (state & TCPF_LISTEN) { + /* MPJ subflow are removed from accept queue before reaching here, + * avoid stray wakeups + */ + if (reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue)) + return; + set_bit(MPTCP_DATA_READY, &msk->flags); parent->sk_data_ready(parent); return; |