net: sched: Fix qdisc_rate_table refcount leak when get tcf_block failed

[ Upstream commit c66070125837900163b81a03063ddd657a7e9bfb ]

The reference counting issue happens in one exception handling path of
cbq_change_class(). When failing to get tcf_block, the function forgets
to decrease the refcount of "rtab" increased by qdisc_put_rtab(),
causing a refcount leak.

Fix this issue by jumping to "failure" label when get tcf_block failed.

Fixes: 6529eaba33 ("net: sched: introduce tcf block infractructure")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Link: https://lore.kernel.org/r/1630252681-71588-1-git-send-email-xiyuyang19@fudan.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Xiyu Yang 2021-08-29 23:58:01 +08:00 committed by AuxXxilium
parent 995644c46b
commit 0a5dc4e135

View File

@ -1614,7 +1614,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct nlattr **t
err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack); err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack);
if (err) { if (err) {
kfree(cl); kfree(cl);
return err; goto failure;
} }
if (tca[TCA_RATE]) { if (tca[TCA_RATE]) {