This is a note to let you know that I've just added the patch titled
net/sched: Reserve TC_H_INGRESS (TC_H_CLSACT) for ingress (clsact) Qdiscs
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-sched-reserve-tc_h_ingress-tc_h_clsact-for-ingre.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9a2921b9225d6c6d8a2021f9640ca0f449d4929f
Author: Peilin Ye <peilin.ye@xxxxxxxxxxxxx>
Date: Mon May 29 12:54:03 2023 -0700
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 <pctammela@xxxxxxxxxxxx>
Acked-by: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
Reviewed-by: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
Reviewed-by: Vlad Buslov <vladbu@xxxxxxxxxx>
Signed-off-by: Peilin Ye <peilin.ye@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 67d6bc97e5fe9..cd6af51bd9ff2 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 9f1ed810b7b89..28168799ca1b8 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,
