renegade-project/linux-snapdragon
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

net: sched: Fix for duplicate class dump

Browse Source 
When dumping classes by parent, kernel would return classes twice:

| # tc qdisc add dev lo root prio
| # tc class show dev lo
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:
| # tc class show dev lo parent 8001:
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:

This comes from qdisc_match_from_root() potentially returning the root
qdisc itself if its handle matched. Though in that case, root's classes
were already dumped a few lines above.

Fixes: cb395b2010 ("net: sched: optimize class dumps")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Phil Sutter 2018-10-18 10:34:26 +02:00 committed by David S. Miller
parent 6b839b6cf9
commit 3c53ed8fef
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
net/sched/sch_api.c
View File

@ -2059,7 +2059,8 @@ static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
if (tcm->tcm_parent) {
q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent));
if (q && tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
if (q && q != root &&
tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
return -1;
return 0;
}