| Message ID | 039d97d7c7d90a52e55aa90760585eea7cb0d027.1613755058.git.pabeni@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | mptcp: a bunch of fixes | expand |
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 8b2338dfdc80..59f992fe6728 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1018,6 +1018,12 @@ 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;
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> --- net/mptcp/subflow.c | 6 ++++++ 1 file changed, 6 insertions(+)