From 8ea4229e9cc6f607b5c42843f5749d1cdf04aaa8 Mon Sep 17 00:00:00 2001
From: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Date: Sun, 29 Aug 2021 23:58:01 +0800
Subject: [PATCH] net: sched: Fix qdisc_rate_table refcount leak when get tcf_block failed
Git-commit: c66070125837900163b81a03063ddd657a7e9bfb
Patch-mainline: v5.15-rc1
References: stable-5.14.4
[ 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: 6529eaba33f0 ("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>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
net/sched/sch_cbq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index b79a7e27bb31..38a3a8394bbd 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -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);
if (err) {
kfree(cl);
- return err;
+ goto failure;
}
if (tca[TCA_RATE]) {
--
2.26.2