From 08d76116827e1680c0a01eb974ded3329c33d607 Mon Sep 17 00:00:00 2001 From: Xiyu Yang Date: Tue, 19 Oct 2021 18:07:55 +0800 Subject: [PATCH] net: sched: Fix qdisc_rate_table refcount leak when get tcf_block failed stable inclusion from stable-5.10.65 commit f96bc82e0348be15def7b98ebfd6e276d2c1e8a1 bugzilla: 182361 https://gitee.com/openeuler/kernel/issues/I4EH3U Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f96bc82e0348be15def7b98ebfd6e276d2c1e8a1 -------------------------------- [ 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 Reviewed-by: Cong Wang Link: https://lore.kernel.org/r/1630252681-71588-1-git-send-email-xiyuyang19@fudan.edu.cn Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin Signed-off-by: Chen Jun Acked-by: Weilong Chen Signed-off-by: Chen Jun Signed-off-by: Zheng Zengkai --- 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 53d45e029c36..4a78fcf5d4f9 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]) { -- GitLab