[net-next,v2,5/5] selftests: test_vxlan_fdb_changelink: Add a test for MC remote change

Commit Message

Petr Machata Feb. 14, 2025, 4:18 p.m. UTC

Changes to MC remote need to be reflected in actual group memberships.
Add a test to verify that it is the case.

Signed-off-by: Petr Machata <[e-mail]>
Reviewed-by: Ido Schimmel <[e-mail]>
Reviewed-by: Nikolay Aleksandrov <[e-mail]>
---

Notes:
CC: Simon Horman <[e-mail]>
CC: Shuah Khan <[e-mail]>
CC: [e-mail]

 .../net/test_vxlan_fdb_changelink.sh          | 76 +++++++++++++++++++
 1 file changed, 76 insertions(+)

Patch

diff --git a/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh b/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh
index 6f2bca4b346c..062f957950af 100755
--- a/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh
+++ b/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh
@@ -3,6 +3,7 @@ 
 
 ALL_TESTS="
 	test_set_remote
+	test_change_mc_remote
 "
 source lib.sh
 
@@ -31,6 +32,81 @@  test_set_remote()
 	log_test 'FDB default-remote handling across "ip link set"'
 }
 
+fmt_remote()
+{
+	local addr=$1; shift
+
+	if [[ $addr == 224.* ]]; then
+		echo "group $addr"
+	else
+		echo "remote $addr"
+	fi
+}
+
+change_remote()
+{
+	local remote=$1; shift
+
+	ip link set dev vx type vxlan $(fmt_remote $remote) dev v1
+}
+
+check_membership()
+{
+	local check_vec=("$@")
+
+	local memberships
+	memberships=$(
+	    netstat -n --groups |
+		sed -n '/^v1\b/p' |
+		grep -o '[^ ]*$'
+	)
+	check_err $? "Couldn't obtain group memberships"
+
+	local item
+	for item in "${check_vec[@]}"; do
+		eval "local $item"
+		echo "$memberships" | grep -q "\b$group\b"
+		check_err_fail $fail $? "$group is_ex reported in IGMP query response"
+	done
+}
+
+test_change_mc_remote()
+{
+	check_command netstat || return
+
+	ip_link_add v1 up type veth peer name v2
+	ip_link_set_up v2
+
+	RET=0
+
+	ip_link_add vx up type vxlan dstport 4789 \
+		local 192.0.2.1 $(fmt_remote 224.1.1.1) dev v1 vni 1000
+
+	check_membership "group=224.1.1.1 fail=0" \
+			 "group=224.1.1.2 fail=1" \
+			 "group=224.1.1.3 fail=1"
+
+	log_test "MC group report after VXLAN creation"
+
+	RET=0
+
+	change_remote 224.1.1.2
+	check_membership "group=224.1.1.1 fail=1" \
+			 "group=224.1.1.2 fail=0" \
+			 "group=224.1.1.3 fail=1"
+
+	log_test "MC group report after changing VXLAN remote MC->MC"
+
+	RET=0
+
+	change_remote 192.0.2.2
+	check_membership "group=224.1.1.1 fail=1" \
+			 "group=224.1.1.2 fail=1" \
+			 "group=224.1.1.3 fail=1"
+
+	log_test "MC group report after changing VXLAN remote MC->UC"
+}
+
 trap defer_scopes_cleanup EXIT
 
 tests_run