From 6e05e46fa821a5c1b281355f1f622ac76cb6080a Mon Sep 17 00:00:00 2001 From: Xuanqiang Luo Date: Thu, 10 Sep 2026 17:34:12 +0800 Subject: [PATCH 1/2] net/sched: act_api: release tail references on DELACTION failure A batched RTM_DELACTION request takes a temporary reference on each action before attempting any deletion. tcf_action_delete() clears each processed slot and drops its temporary reference before attempting the deletion. If deletion fails, tca_action_gd() calls tcf_action_put_many() to release the remaining references, but its tcf_act_for_each_action() iterator stops at the first NULL slot. When a batch stops at an action bound to a filter, this leaks a reference on each subsequent action. A later delete of an unbound action can then return success without removing it from the IDR. Walk the full array in tcf_action_put_many() and skip NULL slots to release the references held on the unprocessed actions. Fixes: a0e947c9ccff ("net/sched: act_api: avoid non-contiguous action array") Cc: stable@vger.kernel.org Signed-off-by: Xuanqiang Luo Link: https://patch.msgid.link/20260910093413.34509-2-xuanqiang.luo@linux.dev Signed-off-by: Jakub Kicinski --- net/sched/act_api.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 19501dc99464..3f653721c45f 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -1218,11 +1218,16 @@ static int tcf_action_put(struct tc_action *p) static void tcf_action_put_many(struct tc_action *actions[]) { - struct tc_action *a; int i; - tcf_act_for_each_action(i, a, actions) { - const struct tc_action_ops *ops = a->ops; + /* Deletion may have cleared entries before failing. */ + for (i = 0; i < TCA_ACT_MAX_PRIO; i++) { + struct tc_action *a = actions[i]; + const struct tc_action_ops *ops; + + if (!a) + continue; + ops = a->ops; if (tcf_action_put(a)) module_put(ops->owner); } From 14c5eb685cdefbd32e73d2723071ecbd8effbce9 Mon Sep 17 00:00:00 2001 From: Xuanqiang Luo Date: Thu, 10 Sep 2026 17:34:13 +0800 Subject: [PATCH 2/2] selftests: tc-testing: test action batch deletion failure cleanup Add tests for cleanup after a batched RTM_DELACTION request fails at a gact action bound to a filter. Check that subsequent actions retain their original reference counts and that earlier successful deletions are preserved. Cover failures at the first and middle entries. Verify that a remaining unbound action can be removed with one subsequent delete. Signed-off-by: Xuanqiang Luo Link: https://patch.msgid.link/20260910093413.34509-3-xuanqiang.luo@linux.dev Signed-off-by: Jakub Kicinski --- .../tc-tests/actions/batch-delete.json | 115 ++++++++++++++++++ 1 file changed, 115 insertions(+) create mode 100644 tools/testing/selftests/tc-testing/tc-tests/actions/batch-delete.json diff --git a/tools/testing/selftests/tc-testing/tc-tests/actions/batch-delete.json b/tools/testing/selftests/tc-testing/tc-tests/actions/batch-delete.json new file mode 100644 index 000000000000..ef7ca4a6775b --- /dev/null +++ b/tools/testing/selftests/tc-testing/tc-tests/actions/batch-delete.json @@ -0,0 +1,115 @@ +[ + { + "id": "d710", + "name": "Release tail references after first action deletion fails", + "category": [ + "actions", + "gact" + ], + "plugins": { + "requires": "nsPlugin" + }, + "setup": [ + [ + "$TC actions flush action gact", + 0, + 1, + 255 + ], + "$TC qdisc add dev $DEV1 ingress", + "$TC actions add action pass index 1", + "$TC actions add action pass index 2", + "$TC actions add action pass index 3", + "$TC filter add dev $DEV1 protocol ip ingress u32 match u32 0 0 action gact index 1" + ], + "cmdUnderTest": "$TC actions del action gact index 1 action gact index 2 action gact index 3", + "expExitCode": "255", + "verifyCmd": "$TC actions ls action gact", + "matchPattern": "total acts 3\\b.*index 1 ref 2 bind 1\\b.*index 2 ref 1 bind 0\\b.*index 3 ref 1 bind 0\\b", + "matchCount": "1", + "teardown": [ + "$TC qdisc del dev $DEV1 ingress", + [ + "$TC actions flush action gact", + 0, + 1, + 255 + ] + ] + }, + { + "id": "d711", + "name": "Release tail references after middle action deletion fails", + "category": [ + "actions", + "gact" + ], + "plugins": { + "requires": "nsPlugin" + }, + "setup": [ + [ + "$TC actions flush action gact", + 0, + 1, + 255 + ], + "$TC qdisc add dev $DEV1 ingress", + "$TC actions add action pass index 1", + "$TC actions add action pass index 2", + "$TC actions add action pass index 3", + "$TC filter add dev $DEV1 protocol ip ingress u32 match u32 0 0 action gact index 2" + ], + "cmdUnderTest": "$TC actions del action gact index 1 action gact index 2 action gact index 3", + "expExitCode": "255", + "verifyCmd": "$TC actions ls action gact", + "matchPattern": "total acts 2\\b.*index 2 ref 2 bind 1\\b.*index 3 ref 1 bind 0\\b", + "matchCount": "1", + "teardown": [ + "$TC qdisc del dev $DEV1 ingress", + [ + "$TC actions flush action gact", + 0, + 1, + 255 + ] + ] + }, + { + "id": "d713", + "name": "Delete a tail action once after a failed batch", + "category": [ + "actions", + "gact" + ], + "plugins": { + "requires": "nsPlugin" + }, + "setup": [ + [ + "$TC actions flush action gact", + 0, + 1, + 255 + ], + "$TC qdisc add dev $DEV1 ingress", + "$TC actions add action pass index 1", + "$TC actions add action pass index 2", + "$TC filter add dev $DEV1 protocol ip ingress u32 match u32 0 0 action gact index 1" + ], + "cmdUnderTest": "$TC actions del action gact index 1 action gact index 2", + "expExitCode": "255", + "verifyCmd": "sh -c '$TC actions del action gact index 2 && $TC actions ls action gact'", + "matchPattern": "total acts 1\\b.*index 1 ref 2 bind 1\\b", + "matchCount": "1", + "teardown": [ + "$TC qdisc del dev $DEV1 ingress", + [ + "$TC actions flush action gact", + 0, + 1, + 255 + ] + ] + } +]