selftests: net: vxlan: Fix selftest regression after changes in iproute2.

The iproute2 output that eventually landed upstream is different than
the one used in this test, resulting in failures. Fix by adjusting the
test to use iproute2's JSON output, which is more stable than regular
output.

Fixes: 305c0418 ("selftests: net: vxlan: Add tests for vxlan nolocalbypass option.")
Signed-off-by: Vladimir Nikishkin <vladimir@nikishkin.pw>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/test_vxlan_nolocalbypass.sh

@@ -130,7 +130,7 @@ nolocalbypass()
 	run_cmd "tc -n ns1 qdisc add dev lo clsact"
 	run_cmd "tc -n ns1 filter add dev lo ingress pref 1 handle 101 proto ip flower ip_proto udp dst_port 4790 action drop"
 
-	run_cmd "ip -n ns1 -d link show dev vx0 | grep ' localbypass'"
+	run_cmd "ip -n ns1 -d -j link show dev vx0 | jq -e '.[][\"linkinfo\"][\"info_data\"][\"localbypass\"] == true'"
 	log_test $? 0 "localbypass enabled"
 
 	run_cmd "ip netns exec ns1 mausezahn vx0 -a $smac -b $dmac -c 1 -p 100 -q"
@@ -140,7 +140,7 @@ nolocalbypass()
 
 	run_cmd "ip -n ns1 link set dev vx0 type vxlan nolocalbypass"
 
-	run_cmd "ip -n ns1 -d link show dev vx0 | grep 'nolocalbypass'"
+	run_cmd "ip -n ns1 -d -j link show dev vx0 | jq -e '.[][\"linkinfo\"][\"info_data\"][\"localbypass\"] == false'"
 	log_test $? 0 "localbypass disabled"
 
 	run_cmd "ip netns exec ns1 mausezahn vx0 -a $smac -b $dmac -c 1 -p 100 -q"
@@ -150,7 +150,7 @@ nolocalbypass()
 
 	run_cmd "ip -n ns1 link set dev vx0 type vxlan localbypass"
 
-	run_cmd "ip -n ns1 -d link show dev vx0 | grep ' localbypass'"
+	run_cmd "ip -n ns1 -d -j link show dev vx0 | jq -e '.[][\"linkinfo\"][\"info_data\"][\"localbypass\"] == true'"
 	log_test $? 0 "localbypass enabled"
 
 	run_cmd "ip netns exec ns1 mausezahn vx0 -a $smac -b $dmac -c 1 -p 100 -q"