Merge branch 'mptcp-userspace-pm-create-sockets-for-the-right-family'

Matthieu Baerts says:

====================
mptcp: userspace pm: create sockets for the right family

Before these patches, the Userspace Path Manager would allow the
creation of subflows with wrong families: taking the one of the MPTCP
socket instead of the provided ones and resulting in the creation of
subflows with likely not the right source and/or destination IPs. It
would also allow the creation of subflows between different families or
not respecting v4/v6-only socket attributes.

Patch 1 lets the userspace PM select the proper family to avoid creating
subflows with the wrong source and/or destination addresses because the
family is not the expected one.

Patch 2 makes sure the userspace PM doesn't allow the userspace to
create subflows for a family that is not allowed.

Patch 3 validates scenarios with a mix of v4 and v6 subflows for the
same MPTCP connection.

These patches fix issues introduced in v5.19 when the userspace path
manager has been introduced.
====================

Link: https://lore.kernel.org/r/20230112-upstream-net-20230112-netlink-v4-v6-v1-0-6a8363a221d2@tessares.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/tools/testing/selftests/net/mptcp/userspace_pm.sh b/tools/testing/selftests/net/mptcp/userspace_pm.sh
index a29deb9fa024..ab2d581f28a1 100755
--- a/tools/testing/selftests/net/mptcp/userspace_pm.sh
+++ b/tools/testing/selftests/net/mptcp/userspace_pm.sh
@@ -752,6 +752,52 @@ test_subflows()
 	   "$server4_token" > /dev/null 2>&1
 }
 
+test_subflows_v4_v6_mix()
+{
+	# Attempt to add a listener at 10.0.2.1:<subflow-port>
+	ip netns exec "$ns1" ./pm_nl_ctl listen 10.0.2.1\
+	   $app6_port > /dev/null 2>&1 &
+	local listener_pid=$!
+
+	# ADD_ADDR4 from server to client machine reusing the subflow port on
+	# the established v6 connection
+	:>"$client_evts"
+	ip netns exec "$ns1" ./pm_nl_ctl ann 10.0.2.1 token "$server6_token" id\
+	   $server_addr_id dev ns1eth2 > /dev/null 2>&1
+	stdbuf -o0 -e0 printf "ADD_ADDR4 id:%d 10.0.2.1 (ns1) => ns2, reuse port\t\t" $server_addr_id
+	sleep 0.5
+	verify_announce_event "$client_evts" "$ANNOUNCED" "$client6_token" "10.0.2.1"\
+			      "$server_addr_id" "$app6_port"
+
+	# CREATE_SUBFLOW from client to server machine
+	:>"$client_evts"
+	ip netns exec "$ns2" ./pm_nl_ctl csf lip 10.0.2.2 lid 23 rip 10.0.2.1 rport\
+	   $app6_port token "$client6_token" > /dev/null 2>&1
+	sleep 0.5
+	verify_subflow_events "$client_evts" "$SUB_ESTABLISHED" "$client6_token"\
+			      "$AF_INET" "10.0.2.2" "10.0.2.1" "$app6_port" "23"\
+			      "$server_addr_id" "ns2" "ns1"
+
+	# Delete the listener from the server ns, if one was created
+	kill_wait $listener_pid
+
+	sport=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
+
+	# DESTROY_SUBFLOW from client to server machine
+	:>"$client_evts"
+	ip netns exec "$ns2" ./pm_nl_ctl dsf lip 10.0.2.2 lport "$sport" rip 10.0.2.1 rport\
+	   $app6_port token "$client6_token" > /dev/null 2>&1
+	sleep 0.5
+	verify_subflow_events "$client_evts" "$SUB_CLOSED" "$client6_token" \
+			      "$AF_INET" "10.0.2.2" "10.0.2.1" "$app6_port" "23"\
+			      "$server_addr_id" "ns2" "ns1"
+
+	# RM_ADDR from server to client machine
+	ip netns exec "$ns1" ./pm_nl_ctl rem id $server_addr_id token\
+	   "$server6_token" > /dev/null 2>&1
+	sleep 0.5
+}
+
 test_prio()
 {
 	local count
@@ -861,6 +907,7 @@ make_connection "v6"
 test_announce
 test_remove
 test_subflows
+test_subflows_v4_v6_mix
 test_prio
 test_listener