The test makes subscribes to link events from all namespaces and makes sure that local events do not carry NSID in their ancillary data (even if there is a self-referential NSID allocated for the local namespace), and remote events do.
Assisted-by: OpenCode:claude-opus-4.6 Signed-off-by: Ilya Maximets <[email protected]> --- tools/testing/selftests/net/link_netns.py | 52 +++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/tools/testing/selftests/net/link_netns.py b/tools/testing/selftests/net/link_netns.py index 2aae422d3f8a6..1e766154cb573 100755 --- a/tools/testing/selftests/net/link_netns.py +++ b/tools/testing/selftests/net/link_netns.py @@ -33,6 +33,57 @@ def test_event() -> None: "Received unexpected link notification") +def test_event_all_nsid() -> None: + """NETLINK_LISTEN_ALL_NSID notifications: local events must not + carry nsid even with a self-referential mapping. Remote events + must carry the correct nsid.""" + + with NetNS() as ns1, NetNS() as ns2: + net1, net2 = str(ns1), str(ns2) + + with NetNSEnter(net1): + rtnl = RtnlFamily() + rtnl.ntf_listen_all_nsid() + rtnl.ntf_subscribe("rtnlgrp-link") + + # Case 1: no nsid assigned, local event, no nsid expected. + ip("link add dummy-lo type dummy", ns=net1) + + # Case 2: self-referential nsid, local event, still no nsid. + ip(f"netns set {net1} {LINK_NETNSID}", ns=net1) + ip("link add dummy-sr type dummy", ns=net1) + + # Case 3: remote event, nsid present. + ip(f"netns set {net2} {LINK_NETNSID2}", ns=net1) + ip("link add dummy-re type dummy", ns=net2) + + # Collect the three newlink events, ignoring unrelated noise. + events = {} + for msg in rtnl.poll_ntf(duration=1): + if msg['name'] == 'getlink': + ifname = msg['msg'].get('ifname') + if ifname in ('dummy-lo', 'dummy-sr', 'dummy-re'): + events[ifname] = msg + if len(events) == 3: + break + + ksft_true('dummy-lo' in events, "missing local event") + ksft_true(events['dummy-lo'].get('nsid') is None, + "local event without nsid should not carry nsid") + + ksft_true('dummy-sr' in events, "missing self-ref event") + ksft_true(events['dummy-sr'].get('nsid') is None, + "local event with self-ref nsid should not carry nsid") + + ksft_true('dummy-re' in events, "missing remote event") + ksft_eq(events['dummy-re'].get('nsid'), LINK_NETNSID2, + "remote event should carry nsid") + + ip("link del dummy-lo", ns=net1) + ip("link del dummy-sr", ns=net1) + ip("link del dummy-re", ns=net2) + + 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: @@ -175,6 +226,7 @@ def test_peer_net_cross_ns() -> None: def main() -> None: ksft_run([ test_event, + test_event_all_nsid, test_link_net, test_peer_net, test_peer_net_cross_ns, -- 2.53.0

