jsauer/torvalds-linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-01-11 17:10:13 +00:00
Code

net/sched: Abort __tc_modify_qdisc if parent is a clsact/ingress qdisc

Browse Source 
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>
This commit is contained in:
Victor Nogueira 2025-11-06 17:56:20 -03:00 committed by Jakub Kicinski
parent 1534ff7775
commit e781122d76
1 changed files with 5 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
net/sched/sch_api.c
View File

@ -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);