From 7b120a771943ffc3cbce787daecdd23eccb0505f Mon Sep 17 00:00:00 2001 From: Jamal Hadi Salim Date: Tue, 25 Aug 2026 04:10:52 -0400 Subject: [PATCH] selftests: tc-testing: add u32 node ID pool exhaustion test Add a tdc test case that fills the u32 node ID space with 4095 auto-generated handles, then attempts to add a 4096th. On the fixed kernel the 4096th filter is rejected with ENOSPC (exit 2). On the unfixed kernel it silently succeeds with a duplicate handle. The setup pipes the 4095 add commands directly into `tc -b -` inside a single bash -c (matching the existing test id 1234 pattern), avoiding any temp file. Signed-off-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260825081052.133898-2-jhs@mojatatu.com Signed-off-by: Jakub Kicinski --- .../tc-testing/tc-tests/filters/u32.json | 23 +++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/tools/testing/selftests/tc-testing/tc-tests/filters/u32.json b/tools/testing/selftests/tc-testing/tc-tests/filters/u32.json index b2ca9d4e991b..e2b03f2b5e89 100644 --- a/tools/testing/selftests/tc-testing/tc-tests/filters/u32.json +++ b/tools/testing/selftests/tc-testing/tc-tests/filters/u32.json @@ -353,5 +353,28 @@ "teardown": [ "$TC qdisc del dev $DEV1 parent root drr" ] + }, + { + "id": "70fd", + "name": "Add u32 filter when node ID pool is exhausted (4096th filter rejected)", + "category": [ + "filter", + "u32" + ], + "plugins": { + "requires": "nsPlugin" + }, + "setup": [ + "$TC qdisc add dev $DUMMY clsact", + "bash -c 'for i in {1..4095}; do echo filter add dev $DUMMY ingress prio 1 protocol ip u32 match u8 0 0 at 0; done | $TC -b -'" + ], + "cmdUnderTest": "$TC filter add dev $DUMMY ingress prio 1 protocol ip u32 match u8 0 0 at 0", + "expExitCode": "2", + "verifyCmd": "$TC -d filter show dev $DUMMY ingress", + "matchPattern": "fh 800::", + "matchCount": "4095", + "teardown": [ + "$TC qdisc del dev $DUMMY clsact" + ] } ]