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From: Stephen Hemminger <stephen@networkplumber.org>
To: netdev@vger.kernel.org
Cc: Victor Nogueira <victor@mojatatu.com>,
	Jamal Hadi Salim <jhs@mojatatu.com>,
	Stephen Hemminger <stephen@networkplumber.org>,
	Jiri Pirko <jiri@resnulli.us>, Shuah Khan <shuah@kernel.org>,
	Paolo Abeni <pabeni@redhat.com>, Jakub Kicinski <kuba@kernel.org>,
	linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST
	FRAMEWORK), linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v3 6/7] selftests/tc-testing: Add mirred test cases exercising loops
Date: Thu, 26 Mar 2026 11:01:05 -0700	[thread overview]
Message-ID: <20260326181701.308275-7-stephen@networkplumber.org> (raw)
In-Reply-To: <20260326181701.308275-1-stephen@networkplumber.org>

From: Victor Nogueira <victor@mojatatu.com>

Add mirred loop test cases to validate that those will be caught and other
test cases that were previously misinterpreted as loops by mirred.

This commit adds 12 test cases:

- Redirect multiport: dummy egress -> dev1 ingress -> dummy egress (Loop)
- Redirect singleport: dev1 ingress -> dev1 egress -> dev1 ingress (Loop)
- Redirect multiport: dev1 ingress -> dummy ingress -> dev1 egress (No Loop)
- Redirect multiport: dev1 ingress -> dummy ingress -> dev1 ingress (Loop)
- Redirect multiport: dev1 ingress -> dummy egress -> dev1 ingress (Loop)
- Redirect multiport: dummy egress -> dev1 ingress -> dummy egress, different prios (Loop)
- Redirect multiport: dev1 ingress -> dummy ingress -> dummy egress -> dev1 egress (No Loop)
- Redirect multiport: dev1 ingress -> dummy egress -> dev1 egress (No Loop)
- Redirect multiport: dev1 ingress -> dummy egress -> dummy ingress (No Loop)
- Redirect singleport: dev1 ingress -> dev1 ingress (Loop)
- Redirect singleport: dummy egress -> dummy ingress (No Loop)
- Redirect multiport: dev1 ingress -> dummy ingress -> dummy egress (No Loop)

Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
---
 .../tc-testing/tc-tests/actions/mirred.json   | 616 +++++++++++++++++-
 1 file changed, 615 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/tc-testing/tc-tests/actions/mirred.json b/tools/testing/selftests/tc-testing/tc-tests/actions/mirred.json
index b056eb966871..d0cad6571691 100644
--- a/tools/testing/selftests/tc-testing/tc-tests/actions/mirred.json
+++ b/tools/testing/selftests/tc-testing/tc-tests/actions/mirred.json
@@ -1144,6 +1144,620 @@
         "teardown": [
             "$TC qdisc del dev $DUMMY clsact"
         ]
+    },
+    {
+        "id": "531c",
+        "name": "Redirect multiport: dummy egress -> dev1 ingress -> dummy egress (Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin"
+            ]
+        },
+        "setup": [
+            "$IP link set dev $DUMMY up || true",
+            "$IP addr add 10.10.10.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY clsact",
+            "$TC filter add dev $DUMMY egress protocol ip prio 10 matchall action mirred ingress redirect dev $DEV1 index 1",
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred egress redirect dev $DUMMY index 2"
+        ],
+        "cmdUnderTest": "ping -c1 -W0.01 -I $DUMMY 10.10.10.1",
+        "expExitCode": "1",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 3
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DUMMY clsact",
+            "$TC qdisc del dev $DEV1 clsact"
+        ]
+    },
+    {
+        "id": "b1d7",
+        "name": "Redirect singleport: dev1 ingress -> dev1 egress -> dev1 ingress (Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred egress redirect dev $DEV1 index 1"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DEV1 egress protocol ip prio 11 matchall action mirred ingress redirect dev $DEV1 index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "egress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 3
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact"
+        ]
+    },
+    {
+        "id": "c66d",
+        "name": "Redirect multiport: dev1 ingress -> dummy ingress -> dev1 egress (No Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred ingress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY ingress protocol ip prio 11 matchall action mirred egress redirect dev $DEV1 index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "aa99",
+        "name": "Redirect multiport: dev1 ingress -> dummy ingress -> dev1 ingress (Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred ingress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY ingress protocol ip prio 11 matchall action mirred ingress redirect dev $DEV1 index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 2,
+                            "overlimits": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "37d7",
+        "name": "Redirect multiport: dev1 ingress -> dummy egress -> dev1 ingress (Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred egress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY egress protocol ip prio 11 matchall action mirred ingress redirect dev $DEV1 index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "egress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 3
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "6d02",
+        "name": "Redirect multiport: dummy egress -> dev1 ingress -> dummy egress, different prios (Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin"
+            ]
+        },
+        "setup": [
+            "$IP link set dev $DUMMY up || true",
+            "$IP addr add 10.10.10.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY clsact",
+            "$TC filter add dev $DUMMY egress protocol ip prio 10 matchall action mirred ingress redirect dev $DEV1 index 1",
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 11 matchall action mirred egress redirect dev $DUMMY index 2"
+        ],
+        "cmdUnderTest": "ping -c1 -W0.01 -I $DUMMY 10.10.10.1",
+        "expExitCode": "1",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 3
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DUMMY clsact",
+            "$TC qdisc del dev $DEV1 clsact"
+        ]
+    },
+    {
+        "id": "8115",
+        "name": "Redirect multiport: dev1 ingress -> dummy ingress -> dummy egress -> dev1 egress (No Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred ingress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact",
+            "$TC filter add dev $DUMMY ingress protocol ip prio 11 matchall action mirred egress redirect dev $DUMMY index 2"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY egress protocol ip prio 12 matchall action mirred egress redirect dev $DEV1 index 3",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "9eb3",
+        "name": "Redirect multiport: dev1 ingress -> dummy egress -> dev1 egress (No Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred egress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY egress protocol ip prio 11 matchall action mirred egress redirect dev $DEV1 index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "egress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "d837",
+        "name": "Redirect multiport: dev1 ingress -> dummy egress -> dummy ingress (No Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred egress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY egress protocol ip prio 11 matchall action mirred ingress redirect dev $DUMMY index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "egress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "2071",
+        "name": "Redirect singleport: dev1 ingress -> dev1 ingress (Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred ingress redirect dev $DEV1 index 1",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1,
+                            "overlimits": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact"
+        ]
+    },
+    {
+        "id": "0101",
+        "name": "Redirect singleport: dummy egress -> dummy ingress (No Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin"
+            ]
+        },
+        "setup": [
+            "$IP addr add 10.10.10.10/24 dev $DUMMY || true",
+            "$TC qdisc add dev $DUMMY clsact",
+            "$TC filter add dev $DUMMY egress protocol ip prio 11 matchall action mirred ingress redirect dev $DUMMY index 1"
+        ],
+        "cmdUnderTest": "ping -c1 -W0.01 -I $DUMMY 10.10.10.1",
+        "expExitCode": "1",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
+    },
+    {
+        "id": "cf97",
+        "name": "Redirect multiport: dev1 ingress -> dummy ingress -> dummy egress (No Loop)",
+        "category": [
+            "filter",
+            "mirred"
+        ],
+        "plugins": {
+            "requires": [
+                "nsPlugin",
+                "scapyPlugin"
+            ]
+        },
+        "setup": [
+            "$TC qdisc add dev $DEV1 clsact",
+            "$TC filter add dev $DEV1 ingress protocol ip prio 10 matchall action mirred ingress redirect dev $DUMMY index 1",
+            "$TC qdisc add dev $DUMMY clsact"
+        ],
+        "cmdUnderTest": "$TC filter add dev $DUMMY ingress protocol ip prio 11 matchall action mirred egress redirect dev $DUMMY index 2",
+        "scapy": [
+            {
+                "iface": "$DEV0",
+                "count": 1,
+                "packet": "Ether()/IP(dst='10.10.10.1', src='10.10.10.10')/ICMP()"
+            }
+        ],
+        "expExitCode": "0",
+        "verifyCmd": "$TC -j -s actions get action mirred index 1",
+        "matchJSON": [
+            {
+                "total acts": 0
+            },
+            {
+                "actions": [
+                    {
+                        "order": 1,
+                        "kind": "mirred",
+                        "mirred_action": "redirect",
+                        "direction": "ingress",
+                        "index": 1,
+                        "stats": {
+                            "packets": 1
+                        },
+                        "not_in_hw": true
+                    }
+                ]
+            }
+        ],
+        "teardown": [
+            "$TC qdisc del dev $DEV1 clsact",
+            "$TC qdisc del dev $DUMMY clsact"
+        ]
     }
-
 ]
-- 
2.53.0


  parent reply	other threads:[~2026-03-26 18:17 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-26 18:00 [PATCH net v3 0/7] net/sched: Fix packet loops in mirred and netem Stephen Hemminger
2026-03-26 18:01 ` [PATCH v3 1/7] net: Introduce skb tc depth field to track packet loops Stephen Hemminger
2026-03-26 18:01 ` [PATCH v3 2/7] net/sched: Revert "net/sched: Restrict conditions for adding duplicating netems to qdisc tree" Stephen Hemminger
2026-03-26 18:01 ` [PATCH v3 3/7] Revert "selftests/tc-testing: Add tests for restrictions on netem duplication" Stephen Hemminger
2026-03-26 18:01 ` [PATCH v3 4/7] net/sched: fix packet loop on netem when duplicate is on Stephen Hemminger
2026-03-27  7:00   ` William Liu
2026-03-26 18:01 ` [PATCH v3 5/7] net/sched: Fix ethx:ingress -> ethy:egress -> ethx:ingress mirred loop Stephen Hemminger
2026-03-26 18:01 ` Stephen Hemminger [this message]
2026-03-26 18:01 ` [PATCH v3 7/7] selftests/tc-testing: Add netem test case exercising loops Stephen Hemminger

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    --in-reply-to=20260326181701.308275-7-stephen@networkplumber.org \
    --to=stephen@networkplumber.org \
    --cc=jhs@mojatatu.com \
    --cc=jiri@resnulli.us \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=shuah@kernel.org \
    --cc=victor@mojatatu.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

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