diff options
| author | Victor Nogueira <victor@mojatatu.com> | 2025-11-06 17:56:20 -0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-11-10 16:57:56 -0800 |
| commit | e781122d76f018ad17752ab1018b3ffbf7fad84e (patch) | |
| tree | ddfbde2541c82b8ae242ab851309bcc2bd63420a | |
| parent | 1534ff77757e44bcc4b98d0196bc5c0052fce5fa (diff) | |
net/sched: Abort __tc_modify_qdisc if parent is a clsact/ingress qdisc
Wang reported an illegal configuration [1] where the user attempts to add a
child qdisc to the ingress qdisc as follows:
tc qdisc add dev eth0 handle ffff:0 ingress
tc qdisc add dev eth0 handle ffe0:0 parent ffff:a fq
To solve this, we reject any configuration attempt to add a child qdisc to
ingress or clsact.
[1] https://lore.kernel.org/netdev/20251105022213.1981982-1-wangliang74@huawei.com/
Fixes: 5e50da01d0ce ("[NET_SCHED]: Fix endless loops (part 2): "simple" qdiscs")
Reported-by: Wang Liang <wangliang74@huawei.com>
Closes: https://lore.kernel.org/netdev/20251105022213.1981982-1-wangliang74@huawei.com/
Reviewed-by: Pedro Tammela <pctammela@mojatatu.ai>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Reviewed-by: Cong Wang <cwang@multikernel.io>
Link: https://patch.msgid.link/20251106205621.3307639-1-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/sched/sch_api.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 1e058b46d3e1..f56b18c8aebf 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -1599,6 +1599,11 @@ static int __tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, NL_SET_ERR_MSG(extack, "Failed to find specified qdisc"); return -ENOENT; } + if (p->flags & TCQ_F_INGRESS) { + NL_SET_ERR_MSG(extack, + "Cannot add children to ingress/clsact qdisc"); + return -EOPNOTSUPP; + } q = qdisc_leaf(p, clid, extack); if (IS_ERR(q)) return PTR_ERR(q); |