[PATCH net] net: sched: fix possible refcount leak in tc_chain_tmplt_add()

From: Hangyu Hua
Date: Mon Jun 05 2023 - 03:03:14 EST


try_module_get can be called in tcf_proto_lookup_ops. So if ops don't
implement the corresponding function we should call module_put to drop
the refcount.

Fixes: 9f407f1768d3 ("net: sched: introduce chain templates")
Signed-off-by: Hangyu Hua <hbh25y@xxxxxxxxx>
---
net/sched/cls_api.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 2621550bfddc..92bfb892e638 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -2952,6 +2952,7 @@ static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
return PTR_ERR(ops);
if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
+ module_put(ops->owner);
return -EOPNOTSUPP;
}

--
2.34.1