Merge branch 'net-fix-bugs-in-device-netns-move-and-rename'

Jakub Kicinski says:

====================
net: fix bugs in device netns-move and rename

Daniel reported issues with the uevents generated during netdev
namespace move, if the netdev is getting renamed at the same time.

While the issue that he actually cares about is not fixed here,
there is a bunch of seemingly obvious other bugs in this code.
Fix the purely networking bugs while the discussion around
the uevent fix is still ongoing.
====================

Link: https://lore.kernel.org/r/20231018013817.2391509-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

2 files changed, 88 insertions, 0 deletions

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 8b017070960d..4a2881d43989 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -34,6 +34,7 @@ TEST_PROGS += gro.sh
 TEST_PROGS += gre_gso.sh
 TEST_PROGS += cmsg_so_mark.sh
 TEST_PROGS += cmsg_time.sh cmsg_ipv6.sh
+TEST_PROGS += netns-name.sh
 TEST_PROGS += srv6_end_dt46_l3vpn_test.sh
 TEST_PROGS += srv6_end_dt4_l3vpn_test.sh
 TEST_PROGS += srv6_end_dt6_l3vpn_test.sh
diff --git a/tools/testing/selftests/net/netns-name.sh b/tools/testing/selftests/net/netns-name.sh
new file mode 100755
index 000000000000..7d3d3fc99461
--- /dev/null
+++ b/tools/testing/selftests/net/netns-name.sh
@@ -0,0 +1,87 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+set -o pipefail
+
+NS=netns-name-test
+DEV=dummy-dev0
+DEV2=dummy-dev1
+ALT_NAME=some-alt-name
+
+RET_CODE=0
+
+cleanup() {
+    ip netns del $NS
+}
+
+trap cleanup EXIT
+
+fail() {
+    echo "ERROR: ${1:-unexpected return code} (ret: $_)" >&2
+    RET_CODE=1
+}
+
+ip netns add $NS
+
+#
+# Test basic move without a rename
+#
+ip -netns $NS link add name $DEV type dummy || fail
+ip -netns $NS link set dev $DEV netns 1 ||
+    fail "Can't perform a netns move"
+ip link show dev $DEV >> /dev/null || fail "Device not found after move"
+ip link del $DEV || fail
+
+#
+# Test move with a conflict
+#
+ip link add name $DEV type dummy
+ip -netns $NS link add name $DEV type dummy || fail
+ip -netns $NS link set dev $DEV netns 1 2> /dev/null &&
+    fail "Performed a netns move with a name conflict"
+ip link show dev $DEV >> /dev/null || fail "Device not found after move"
+ip -netns $NS link del $DEV || fail
+ip link del $DEV || fail
+
+#
+# Test move with a conflict and rename
+#
+ip link add name $DEV type dummy
+ip -netns $NS link add name $DEV type dummy || fail
+ip -netns $NS link set dev $DEV netns 1 name $DEV2 ||
+    fail "Can't perform a netns move with rename"
+ip link del $DEV2 || fail
+ip link del $DEV || fail
+
+#
+# Test dup alt-name with netns move
+#
+ip link add name $DEV type dummy || fail
+ip link property add dev $DEV altname $ALT_NAME || fail
+ip -netns $NS link add name $DEV2 type dummy || fail
+ip -netns $NS link property add dev $DEV2 altname $ALT_NAME || fail
+
+ip -netns $NS link set dev $DEV2 netns 1 2> /dev/null &&
+    fail "Moved with alt-name dup"
+
+ip link del $DEV || fail
+ip -netns $NS link del $DEV2 || fail
+
+#
+# Test creating alt-name in one net-ns and using in another
+#
+ip -netns $NS link add name $DEV type dummy || fail
+ip -netns $NS link property add dev $DEV altname $ALT_NAME || fail
+ip -netns $NS link set dev $DEV netns 1 || fail
+ip link show dev $ALT_NAME >> /dev/null || fail "Can't find alt-name after move"
+ip  -netns $NS link show dev $ALT_NAME 2> /dev/null &&
+    fail "Can still find alt-name after move"
+ip link del $DEV || fail
+
+echo -ne "$(basename $0) \t\t\t\t"
+if [ $RET_CODE -eq 0 ]; then
+    echo "[  OK  ]"
+else
+    echo "[ FAIL ]"
+fi
+exit $RET_CODE