From 80b20d528a712de5dd2d417d912bf9cb7c4d9b7c Mon Sep 17 00:00:00 2001 From: Peilin Ye Date: Mon, 29 May 2023 12:54:03 -0700 Subject: [PATCH] net/sched: Reserve TC_H_INGRESS (TC_H_CLSACT) for ingress (clsact) Qdiscs [ Upstream commit f85fa45d4a9408d98c46c8fa45ba2e3b2f4bf219 ] Currently it is possible to add e.g. an HTB Qdisc under ffff:fff1 (TC_H_INGRESS, TC_H_CLSACT): $ ip link add name ifb0 type ifb $ tc qdisc add dev ifb0 parent ffff:fff1 htb $ tc qdisc add dev ifb0 clsact Error: Exclusivity flag on, cannot modify. $ drgn ... >>> ifb0 = netdev_get_by_name(prog, "ifb0") >>> qdisc = ifb0.ingress_queue.qdisc_sleeping >>> print(qdisc.ops.id.string_().decode()) htb >>> qdisc.flags.value_() # TCQ_F_INGRESS 2 Only allow ingress and clsact Qdiscs under ffff:fff1. Return -EINVAL for everything else. Make TCQ_F_INGRESS a static flag of ingress and clsact Qdiscs. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: 1f211a1b929c ("net, sched: add clsact qdisc") Tested-by: Pedro Tammela Acked-by: Jamal Hadi Salim Reviewed-by: Jamal Hadi Salim Reviewed-by: Vlad Buslov Signed-off-by: Peilin Ye Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_api.c | 7 ++++++- net/sched/sch_ingress.c | 4 ++-- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 67d6bc97e5fe..cd6af51bd9ff 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -1214,7 +1214,12 @@ static struct Qdisc *qdisc_create(struct net_device *dev, sch->parent = parent; if (handle == TC_H_INGRESS) { - sch->flags |= TCQ_F_INGRESS; + if (!(sch->flags & TCQ_F_INGRESS)) { + NL_SET_ERR_MSG(extack, + "Specified parent ID is reserved for ingress and clsact Qdiscs"); + err = -EINVAL; + goto err_out3; + } handle = TC_H_MAKE(TC_H_INGRESS, 0); } else { if (handle == 0) { diff --git a/net/sched/sch_ingress.c b/net/sched/sch_ingress.c index 9f1ed810b7b8..28168799ca1b 100644 --- a/net/sched/sch_ingress.c +++ b/net/sched/sch_ingress.c @@ -133,7 +133,7 @@ static struct Qdisc_ops ingress_qdisc_ops __read_mostly = { .cl_ops = &ingress_class_ops, .id = "ingress", .priv_size = sizeof(struct ingress_sched_data), - .static_flags = TCQ_F_CPUSTATS, + .static_flags = TCQ_F_INGRESS | TCQ_F_CPUSTATS, .init = ingress_init, .destroy = ingress_destroy, .dump = ingress_dump, @@ -272,7 +272,7 @@ static struct Qdisc_ops clsact_qdisc_ops __read_mostly = { .cl_ops = &clsact_class_ops, .id = "clsact", .priv_size = sizeof(struct clsact_sched_data), - .static_flags = TCQ_F_CPUSTATS, + .static_flags = TCQ_F_INGRESS | TCQ_F_CPUSTATS, .init = clsact_init, .destroy = clsact_destroy, .dump = ingress_dump,