netem: free skb's in tree on reset

[ Upstream commit ff704050f2fc0f3382b5a70bba56a51a3feca79d ]

Netem can leak memory because packets get stored in red-black
tree and it is not cleared on reset.

Reported by: Сергеев Сергей <adron@yapic.net>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 7dc79940f24011d48ce7c0d33f805f82fe776a11..3626010e8f0b18d138571d4700503e86f7f61ccb 100644 (file)
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -358,6 +358,21 @@ static psched_time_t packet_len_2_sched_time(unsigned int len, struct netem_sche
        return PSCHED_NS2TICKS(ticks);
 }
 
+static void tfifo_reset(struct Qdisc *sch)
+{
+       struct netem_sched_data *q = qdisc_priv(sch);
+       struct rb_node *p;
+
+       while ((p = rb_first(&q->t_root))) {
+               struct sk_buff *skb = netem_rb_to_skb(p);
+
+               rb_erase(p, &q->t_root);
+               skb->next = NULL;
+               skb->prev = NULL;
+               kfree_skb(skb);
+       }
+}
+
 static void tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch)
 {
        struct netem_sched_data *q = qdisc_priv(sch);
@@ -613,6 +628,7 @@ static void netem_reset(struct Qdisc *sch)
        struct netem_sched_data *q = qdisc_priv(sch);
 
        qdisc_reset_queue(sch);
+       tfifo_reset(sch);
        if (q->qdisc)
                qdisc_reset(q->qdisc);
        qdisc_watchdog_cancel(&q->watchdog);