From 23b839867868d0c2e95bbe3eb90bfa642ec4212f Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 22 Sep 2020 10:16:16 +0800 Subject: [PATCH] net_sched: fix a memory leak in atm_tc_init() stable inclusion from linux-4.19.134 commit 1343c5394537d9a7c6faac028462fe4df6d8254d -------------------------------- [ Upstream commit 306381aec7c2b5a658eebca008c8a1b666536cba ] When tcf_block_get() fails inside atm_tc_init(), atm_tc_put() is called to release the qdisc p->link.q. But the flow->ref prevents it to do so, as the flow->ref is still zero. Fix this by moving the p->link.ref initialization before tcf_block_get(). Fixes: 6529eaba33f0 ("net: sched: introduce tcf block infractructure") Reported-and-tested-by: syzbot+d411cff6ab29cc2c311b@syzkaller.appspotmail.com Cc: Jamal Hadi Salim Cc: Jiri Pirko Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang Signed-off-by: Li Aichun Reviewed-by: guodeqing Signed-off-by: Yang Yingliang --- net/sched/sch_atm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c index cd49afca9617..91bd5c839303 100644 --- a/net/sched/sch_atm.c +++ b/net/sched/sch_atm.c @@ -551,16 +551,16 @@ static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt, if (!p->link.q) p->link.q = &noop_qdisc; pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q); + p->link.vcc = NULL; + p->link.sock = NULL; + p->link.common.classid = sch->handle; + p->link.ref = 1; err = tcf_block_get(&p->link.block, &p->link.filter_list, sch, extack); if (err) return err; - p->link.vcc = NULL; - p->link.sock = NULL; - p->link.common.classid = sch->handle; - p->link.ref = 1; tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch); return 0; } -- GitLab