[patch net] net: sched: fix memleak for chain zero
From: Jiri Pirko <jiri@resnulli.us>
Date: 2017-09-06 11:14:22
Subsystem:
networking [general], tc subsystem, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
From: Jiri Pirko <redacted>
There's a memleak happening for chain 0. The thing is, chain 0 needs to
be always present, not created on demand. Therefore tcf_block_get upon
creation of block calls the tcf_chain_create function directly. The
chain is created with refcnt == 1, which is not correct in this case and
causes the memleak. So move the refcnt increment into tcf_chain_get
function even for the case when chain needs to be created.
Reported-by: Jakub Kicinski <redacted>
Fixes: 5bc1701881e3 ("net: sched: introduce multichain support for filters")
Signed-off-by: Jiri Pirko <redacted>
---
net/sched/cls_api.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 6c5ea84..30ef466 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c@@ -197,7 +197,7 @@ static struct tcf_chain *tcf_chain_create(struct tcf_block *block, list_add_tail(&chain->list, &block->chain_list); chain->block = block; chain->index = chain_index; - chain->refcnt = 1; + chain->refcnt = 0; return chain; }
@@ -232,15 +232,15 @@ struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index, struct tcf_chain *chain; list_for_each_entry(chain, &block->chain_list, list) { - if (chain->index == chain_index) { - chain->refcnt++; - return chain; - } + if (chain->index == chain_index) + goto incref; } - if (create) - return tcf_chain_create(block, chain_index); - else - return NULL; + chain = create ? tcf_chain_create(block, chain_index) : NULL; + +incref: + if (chain) + chain->refcnt++; + return chain; } EXPORT_SYMBOL(tcf_chain_get);
--
2.9.3