Fix route_address_set duplicated IP sets causing route creation failure

The FlatMap calls pre-populated routeAddressSet and routeExcludeAddressSet
before the for-loops which appended the same IP sets again, doubling every
entry. On Windows this caused CreateIpForwardEntry2 to return
ERROR_OBJECT_ALREADY_EXISTS.

Fixes #3725

Author: nekohasekai

protocol/tun/inbound.go

@@ -324,7 +324,6 @@ func (t *Inbound) Start(stage adapter.StartStage) error {
 			t.tunOptions.Name = tun.CalculateInterfaceName("")
 		}
 		if t.platformInterface == nil {
-			t.routeAddressSet = common.FlatMap(t.routeRuleSet, adapter.RuleSet.ExtractIPSet)
 			for _, routeRuleSet := range t.routeRuleSet {
 				ipSets := routeRuleSet.ExtractIPSet()
 				if len(ipSets) == 0 {
@@ -336,7 +335,6 @@ func (t *Inbound) Start(stage adapter.StartStage) error {
 					t.routeRuleSetCallback = append(t.routeRuleSetCallback, routeRuleSet.RegisterCallback(t.updateRouteAddressSet))
 				}
 			}
-			t.routeExcludeAddressSet = common.FlatMap(t.routeExcludeRuleSet, adapter.RuleSet.ExtractIPSet)
 			for _, routeExcludeRuleSet := range t.routeExcludeRuleSet {
 				ipSets := routeExcludeRuleSet.ExtractIPSet()
 				if len(ipSets) == 0 {