From 8a6e9c670341db1ee913e3888cb44a08f18e7489 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 28 Jun 2016 10:30:08 +0200 Subject: [PATCH] net_sched: netem: do not call qdisc_drop() with a NULL skb If skb_unshare() fails, we call qdisc_drop() with a NULL skb, which is no longer supported. Fixes: 520ac30f4551 ("net_sched: drop packets after root qdisc lock is released") Signed-off-by: Eric Dumazet Reported-by: Dan Carpenter Signed-off-by: David S. Miller --- net/sched/sch_netem.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index ccca8ca4c722..6eac3d880048 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -487,10 +487,14 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch, skb = segs; segs = segs->next; - if (!(skb = skb_unshare(skb, GFP_ATOMIC)) || - (skb->ip_summed == CHECKSUM_PARTIAL && - skb_checksum_help(skb))) { - rc = qdisc_drop(skb, sch, to_free); + skb = skb_unshare(skb, GFP_ATOMIC); + if (unlikely(!skb)) { + qdisc_qstats_drop(sch); + goto finish_segs; + } + if (skb->ip_summed == CHECKSUM_PARTIAL && + skb_checksum_help(skb)) { + qdisc_drop(skb, sch, to_free); goto finish_segs; } -- 2.20.1