From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 341c65242fe18aac8900e4291d472df9f7ba7bc7 ]
Currently we move orphaned msk sockets directly from FIN_WAIT2 state to CLOSE, with the rationale that incoming additional data could be just dropped by the TCP stack/TW sockets.
Anyhow we miss sending MPTCP-level ack on incoming DATA_FIN, and that may hang the peers.
Fixes: e16163b6e2b7 ("mptcp: refactor shutdown and close") 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: Sasha Levin sashal@kernel.org --- net/mptcp/protocol.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 67483e561b37..88f2d900a347 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2292,13 +2292,12 @@ static void mptcp_worker(struct work_struct *work) __mptcp_check_send_data_fin(sk); mptcp_check_data_fin(sk);
- /* if the msk data is completely acked, or the socket timedout, - * there is no point in keeping around an orphaned sk + /* There is no point in keeping around an orphaned sk timedout or + * closed, but we need the msk around to reply to incoming DATA_FIN, + * even if it is orphaned and in FIN_WAIT2 state */ if (sock_flag(sk, SOCK_DEAD) && - (mptcp_check_close_timeout(sk) || - (state != sk->sk_state && - ((1 << inet_sk_state_load(sk)) & (TCPF_CLOSE | TCPF_FIN_WAIT2))))) { + (mptcp_check_close_timeout(sk) || sk->sk_state == TCP_CLOSE)) { inet_sk_state_store(sk, TCP_CLOSE); __mptcp_destroy_sock(sk); goto unlock;