5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
commit db0a37b7ac27d8ca27d3dc676a16d081c16ec7b9 upstream.
In a previous fix, the in-kernel path-manager has been modified not to
retrigger the removal of a subflow if it was already closed, e.g. when
the initial subflow is removed, but kept in the subflows list.
To be complete, this fix should also skip the subflows that are in any
closing state: mptcp_close_ssk() will initiate the closure, but the
switch to the TCP_CLOSE state depends on the other peer.
Fixes: 58e1b66b4e4b ("mptcp: pm: do not remove already closed subflows")
Cc: stable@xxxxxxxxxxxxxxx
Suggested-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Acked-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Link: https://patch.msgid.link/20241008-net-mptcp-fallback-fixes-v1-4-c6fb8e93e551@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mptcp/pm_netlink.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -778,7 +778,8 @@ static void mptcp_pm_nl_rm_addr_or_subfl
int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
u8 id = subflow->local_id;
- if (inet_sk_state_load(ssk) == TCP_CLOSE)
+ if ((1 << inet_sk_state_load(ssk)) &
+ (TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING | TCPF_CLOSE))
continue;
if (rm_type == MPTCP_MIB_RMADDR)
