From 7b9364050246bd4c24b36b71c8990b2922dcc027 Mon Sep 17 00:00:00 2001 From: "Reshetova, Elena" Date: Tue, 4 Jul 2017 15:53:07 +0300 Subject: net, sched: convert Qdisc.refcnt from atomic_t to refcount_t refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller --- net/sched/sch_api.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'net/sched/sch_api.c') diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 43b94c7b69bd..bd24a550e0f9 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -839,7 +839,7 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, old = dev_graft_qdisc(dev_queue, new); if (new && i > 0) - atomic_inc(&new->refcnt); + refcount_inc(&new->refcnt); if (!ingress) qdisc_destroy(old); @@ -850,7 +850,7 @@ skip: notify_and_destroy(net, skb, n, classid, dev->qdisc, new); if (new && !new->ops->attach) - atomic_inc(&new->refcnt); + refcount_inc(&new->refcnt); dev->qdisc = new ? : &noop_qdisc; if (new && new->ops->attach) @@ -1259,7 +1259,7 @@ replay: if (q == p || (p && check_loop(q, p, 0))) return -ELOOP; - atomic_inc(&q->refcnt); + refcount_inc(&q->refcnt); goto graft; } else { if (!q) @@ -1374,7 +1374,7 @@ static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, tcm->tcm_ifindex = qdisc_dev(q)->ifindex; tcm->tcm_parent = clid; tcm->tcm_handle = q->handle; - tcm->tcm_info = atomic_read(&q->refcnt); + tcm->tcm_info = refcount_read(&q->refcnt); if (nla_put_string(skb, TCA_KIND, q->ops->id)) goto nla_put_failure; if (q->ops->dump && q->ops->dump(q, skb) < 0) -- cgit v1.2.3