mptcp: send out MP_FAIL when data checksum fails
When a bad checksum is detected, set the send_mp_fail flag to send out
the MP_FAIL option.
Add a new function mptcp_has_another_subflow() to check whether there's
only a single subflow.
When multiple subflows are in use, close the affected subflow with a RST
that includes an MP_FAIL option and discard the data with the bad
checksum.
Set the sk_state of the subsocket to TCP_CLOSE, then the flag
MPTCP_WORK_CLOSE_SUBFLOW will be set in subflow_sched_work_if_closed,
and the subflow will be closed.
When a single subfow is in use, temporarily handled by sending MP_FAIL
with a RST too.
Signed-off-by: Geliang Tang <geliangtang@xiaomi.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 9ee5676..57a50b11 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -614,6 +614,19 @@ static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
}
+static inline bool mptcp_has_another_subflow(struct sock *ssk)
+{
+ struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk), *tmp;
+ struct mptcp_sock *msk = mptcp_sk(subflow->conn);
+
+ mptcp_for_each_subflow(msk, tmp) {
+ if (tmp != subflow)
+ return true;
+ }
+
+ return false;
+}
+
void __init mptcp_proto_init(void);
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
int __init mptcp_proto_v6_init(void);