[PATCH net-next v8 11/11] selftests: net: Add test cases for link and peer netns

Xiao Liang
2025-01-13T14:39:14Z

- Add test for creating link in another netns when a link of the same
name and ifindex exists in current netns.
- Add test to verify that link is created in target netns directly -
no link new/del events should be generated in link netns or current
netns.
- Add test cases to verify that link-netns is set as expected for
various drivers and combination of namespace-related parameters.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
tools/testing/selftests/net/Makefile | 1 +
tools/testing/selftests/net/config | 5 +
tools/testing/selftests/net/link_netns.py | 141 ++++++++++++++++++++++
tools/testing/selftests/net/netns-name.sh | 10 ++
4 files changed, 157 insertions(+)
create mode 100755 tools/testing/selftests/net/link_netns.py

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 73ee88d6b043..df07a38f884f 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -35,6 +35,7 @@ TEST_PROGS += cmsg_so_mark.sh
TEST_PROGS += cmsg_so_priority.sh
TEST_PROGS += cmsg_time.sh cmsg_ipv6.sh
TEST_PROGS += netns-name.sh
+TEST_PROGS += link_netns.py
TEST_PROGS += nl_netdev.py
TEST_PROGS += srv6_end_dt46_l3vpn_test.sh
TEST_PROGS += srv6_end_dt4_l3vpn_test.sh
diff --git a/tools/testing/selftests/net/config b/tools/testing/selftests/net/config
index 5b9baf708950..ab55270669ec 100644
--- a/tools/testing/selftests/net/config
+++ b/tools/testing/selftests/net/config
@@ -107,3 +107,8 @@ CONFIG_XFRM_INTERFACE=m
CONFIG_XFRM_USER=m
CONFIG_IP_NF_MATCH_RPFILTER=m
CONFIG_IP6_NF_MATCH_RPFILTER=m
+CONFIG_IPVLAN=m
+CONFIG_CAN=m
+CONFIG_CAN_DEV=m
+CONFIG_CAN_VXCAN=m
+CONFIG_NETKIT=y
diff --git a/tools/testing/selftests/net/link_netns.py b/tools/testing/selftests/net/link_netns.py
new file mode 100755
index 000000000000..aab043c59d69
--- /dev/null
+++ b/tools/testing/selftests/net/link_netns.py
@@ -0,0 +1,141 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+import time
+
+from lib.py import ksft_run, ksft_exit, ksft_true
+from lib.py import ip
+from lib.py import NetNS, NetNSEnter
+from lib.py import RtnlFamily
+
+
+LINK_NETNSID = 100
+
+
+def test_event() -> None:
+ with NetNS() as ns1, NetNS() as ns2:
+ with NetNSEnter(str(ns2)):
+ rtnl = RtnlFamily()
+
+ rtnl.ntf_subscribe("rtnlgrp-link")
+
+ ip(f"netns set {ns2} {LINK_NETNSID}", ns=str(ns1))
+ ip(f"link add netns {ns1} link-netnsid {LINK_NETNSID} dummy1 type dummy")
+ ip(f"link add netns {ns1} dummy2 type dummy", ns=str(ns2))
+
+ ip("link del dummy1", ns=str(ns1))
+ ip("link del dummy2", ns=str(ns1))
+
+ time.sleep(1)
+ rtnl.check_ntf()
+ ksft_true(rtnl.async_msg_queue.empty(),
+ "Received unexpected link notification")
+
+
+def validate_link_netns(netns, ifname, link_netnsid) -> bool:
+ link_info = ip(f"-d link show dev {ifname}", ns=netns, json=True)
+ if not link_info:
+ return False
+ return link_info[0].get("link_netnsid") == link_netnsid
+
+
+def test_link_net() -> None:
+ configs = [
+ # type, common args, type args, fallback to dev_net
+ ("ipvlan", "link dummy1", "", False),
+ ("macsec", "link dummy1", "", False),
+ ("macvlan", "link dummy1", "", False),
+ ("macvtap", "link dummy1", "", False),
+ ("vlan", "link dummy1", "id 100", False),
+ ("gre", "", "local 192.0.2.1", True),
+ ("vti", "", "local 192.0.2.1", True),
+ ("ipip", "", "local 192.0.2.1", True),
+ ("ip6gre", "", "local 2001:db8::1", True),
+ ("ip6tnl", "", "local 2001:db8::1", True),
+ ("vti6", "", "local 2001:db8::1", True),
+ ("sit", "", "local 192.0.2.1", True),
+ ("xfrm", "", "if_id 1", True),
+ ]
+
+ with NetNS() as ns1, NetNS() as ns2, NetNS() as ns3:
+ net1, net2, net3 = str(ns1), str(ns2), str(ns3)
+
+ # prepare link netnsid and a dummy link needed by certain drivers
+ ip(f"netns set {net3} {LINK_NETNSID}", ns=str(net2))
+ ip("link add dummy1 type dummy", ns=net3)
+
+ cases = [
+ # source, "netns", "link-netns", expected link-netns
+ (net3, None, None, None, None),
+ (net3, net2, None, None, LINK_NETNSID),
+ (net2, None, net3, LINK_NETNSID, LINK_NETNSID),
+ (net1, net2, net3, LINK_NETNSID, LINK_NETNSID),
+ ]
+
+ for src_net, netns, link_netns, exp1, exp2 in cases:
+ tgt_net = netns or src_net
+ for typ, cargs, targs, fb_dev_net in configs:
+ cmd = "link add"
+ if netns:
+ cmd += f" netns {netns}"
+ if link_netns:
+ cmd += f" link-netns {link_netns}"
+ cmd += f" {cargs} foo type {typ} {targs}"
+ ip(cmd, ns=src_net)
+ if fb_dev_net:
+ ksft_true(validate_link_netns(tgt_net, "foo", exp1),
+ f"{typ} link_netns validation failed")
+ else:
+ ksft_true(validate_link_netns(tgt_net, "foo", exp2),
+ f"{typ} link_netns validation failed")
+ ip(f"link del foo", ns=tgt_net)
+
+
+def test_peer_net() -> None:
+ types = [
+ "vxcan",
+ "netkit",
+ "veth",
+ ]
+
+ with NetNS() as ns1, NetNS() as ns2, NetNS() as ns3, NetNS() as ns4:
+ net1, net2, net3, net4 = str(ns1), str(ns2), str(ns3), str(ns4)
+
+ ip(f"netns set {net3} {LINK_NETNSID}", ns=str(net2))
+
+ cases = [
+ # source, "netns", "link-netns", "peer netns", expected
+ (net1, None, None, None, None),
+ (net1, net2, None, None, None),
+ (net2, None, net3, None, LINK_NETNSID),
+ (net1, net2, net3, None, None),
+ (net2, None, None, net3, LINK_NETNSID),
+ (net1, net2, None, net3, LINK_NETNSID),
+ (net2, None, net2, net3, LINK_NETNSID),
+ (net1, net2, net4, net3, LINK_NETNSID),
+ ]
+
+ for src_net, netns, link_netns, peer_netns, exp in cases:
+ tgt_net = netns or src_net
+ for typ in types:
+ cmd = "link add"
+ if netns:
+ cmd += f" netns {netns}"
+ if link_netns:
+ cmd += f" link-netns {link_netns}"
+ cmd += f" foo type {typ}"
+ if peer_netns:
+ cmd += f" peer netns {peer_netns}"
+ ip(cmd, ns=src_net)
+ ksft_true(validate_link_netns(tgt_net, "foo", exp),
+ f"{typ} peer_netns validation failed")
+ ip(f"link del foo", ns=tgt_net)
+
+
+def main() -> None:
+ ksft_run([test_event, test_link_net, test_peer_net])
+ ksft_exit()
+
+
+if __name__ == "__main__":
+ main()
diff --git a/tools/testing/selftests/net/netns-name.sh b/tools/testing/selftests/net/netns-name.sh
index 6974474c26f3..0be1905d1f2f 100755
--- a/tools/testing/selftests/net/netns-name.sh
+++ b/tools/testing/selftests/net/netns-name.sh
@@ -78,6 +78,16 @@ ip -netns $NS link show dev $ALT_NAME 2> /dev/null &&
fail "Can still find alt-name after move"
ip -netns $test_ns link del $DEV || fail

+#
+# Test no conflict of the same name/ifindex in different netns
+#
+ip -netns $NS link add name $DEV index 100 type dummy || fail
+ip -netns $NS link add netns $test_ns name $DEV index 100 type dummy ||
+ fail "Can create in netns without moving"
+ip -netns $test_ns link show dev $DEV >> /dev/null || fail "Device not found"
+ip -netns $NS link del $DEV || fail
+ip -netns $test_ns link del $DEV || fail
+
echo -ne "$(basename $0) \t\t\t\t"
if [ $RET_CODE -eq 0 ]; then
echo "[ OK ]"
--
2.47.1