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| author | Paolo Abeni <pabeni@redhat.com> | 2021-02-19 18:35:40 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-07 12:35:47 +0100 |
| commit | d3b762715998a001cfb6eac5f6fc93a702e5679d (patch) | |
| tree | 1919205c041e898864e74437e3287a9cb23082e1 /net | |
| parent | c90751e08834e212cf45c95f10d27a661d55cf29 (diff) | |
| download | linux-stable-d3b762715998a001cfb6eac5f6fc93a702e5679d.tar.gz linux-stable-d3b762715998a001cfb6eac5f6fc93a702e5679d.tar.bz2 linux-stable-d3b762715998a001cfb6eac5f6fc93a702e5679d.zip | |
mptcp: do not wakeup listener for MPJ subflows
commit 52557dbc7538ecceb27ef2206719a47a8039a335 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -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 278cbe3e539e..9d28f6e3dc49 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1026,6 +1026,12 @@ 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; |