From e4acf4274169fb6106d4ac854c87071b9764a00d Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Sun, 5 May 2019 22:50:19 +0100 Subject: [PATCH] taprio: add null check on sched_nest to avoid potential null pointer dereference The call to nla_nest_start_noflag can return a null pointer and currently this is not being checked and this can lead to a null pointer dereference when the null pointer sched_nest is passed to function nla_nest_end. Fix this by adding in a null pointer check. Addresses-Coverity: ("Dereference null return value") Fixes: a3d43c0d56f1 ("taprio: Add support adding an admin schedule") Signed-off-by: Colin Ian King Acked-by: Cong Wang Signed-off-by: David S. Miller --- net/sched/sch_taprio.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 539677120b9f..9ecfb8f5902a 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1087,6 +1087,8 @@ static int taprio_dump(struct Qdisc *sch, struct sk_buff *skb) goto done; sched_nest = nla_nest_start_noflag(skb, TCA_TAPRIO_ATTR_ADMIN_SCHED); + if (!sched_nest) + goto options_error; if (dump_schedule(skb, admin)) goto admin_error;