From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 0e4f35d7880157ceccf0a58377d778b02762af82 ]
The msk can close MP_JOIN subflows if the initial handshake fails. Currently such subflows are kept alive in the conn_list until the msk itself is closed.
Beyond the wasted memory, we could end-up sending the DATA_FIN and the DATA_FIN ack on such socket, even after a reset.
Fixes: 43b54c6ee382 ("mptcp: Use full MPTCP-level disconnect state machine") 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 --- net/mptcp/protocol.c | 17 +++++++++++++++++ net/mptcp/protocol.h | 1 + net/mptcp/subflow.c | 6 ++++++ 3 files changed, 24 insertions(+)
--- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1383,6 +1383,20 @@ static void pm_work(struct mptcp_sock *m spin_unlock_bh(&msk->pm.lock); }
+static void __mptcp_close_subflow(struct mptcp_sock *msk) +{ + struct mptcp_subflow_context *subflow, *tmp; + + list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + + if (inet_sk_state_load(ssk) != TCP_CLOSE) + continue; + + __mptcp_close_ssk((struct sock *)msk, ssk, subflow, 0); + } +} + static void mptcp_worker(struct work_struct *work) { struct mptcp_sock *msk = container_of(work, struct mptcp_sock, work); @@ -1400,6 +1414,9 @@ static void mptcp_worker(struct work_str mptcp_clean_una(sk); mptcp_check_data_fin_ack(sk); __mptcp_flush_join_list(msk); + if (test_and_clear_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags)) + __mptcp_close_subflow(msk); + __mptcp_move_skbs(msk);
if (msk->pm.status) --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -90,6 +90,7 @@ #define MPTCP_WORK_RTX 2 #define MPTCP_WORK_EOF 3 #define MPTCP_FALLBACK_DONE 4 +#define MPTCP_WORK_CLOSE_SUBFLOW 5
struct mptcp_options_received { u64 sndr_key; --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -272,9 +272,15 @@ static bool subflow_thmac_valid(struct m
void mptcp_subflow_reset(struct sock *ssk) { + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); + struct sock *sk = subflow->conn; + tcp_set_state(ssk, TCP_CLOSE); tcp_send_active_reset(ssk, GFP_ATOMIC); tcp_done(ssk); + if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags) && + schedule_work(&mptcp_sk(sk)->work)) + sock_hold(sk); }
static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)