Skip tun interface traffic in prerouting UDP/ICMP chain

redirect_nftables.go

@@ -192,6 +192,25 @@ func (r *autoRedirect) setupNFTables() error {
 				},
 			},
 		})
+		nft.AddRule(&nftables.Rule{
+			Table: table,
+			Chain: chainPreRoutingUDP,
+			Exprs: []expr.Any{
+				&expr.Meta{
+					Key:      expr.MetaKeyIIFNAME,
+					Register: 1,
+				},
+				&expr.Cmp{
+					Op:       expr.CmpOpEq,
+					Register: 1,
+					Data:     nftablesIfname(r.tunOptions.Name),
+				},
+				&expr.Counter{},
+				&expr.Verdict{
+					Kind: expr.VerdictReturn,
+				},
+			},
+		})
 		nft.AddRule(&nftables.Rule{
 			Table: table,
 			Chain: chainPreRoutingUDP,