net: sched: avoid duplicates in classes dump

BugLink: https://bugs.launchpad.net/bugs/1920246
commit bfc2560563586372212b0a8aeca7428975fa91fe upstream.

This is a follow up of commit ea3274695353 ("net: sched: avoid
duplicates in qdisc dump") which has fixed the issue only for the qdisc
dump.

The duplicate printing also occurs when dumping the classes via
  tc class show dev eth0

Fixes: 59cc1f61f09c ("net: sched: convert qdisc linked list to hashtable")
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index b65a405f607b235cddfb1ea3bc7cc892cd5571ad..3b1b5ee521379788de424dc732f1aaeccacdf70b 100644 (file)
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -2157,7 +2157,7 @@ static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
 
 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
                               struct tcmsg *tcm, struct netlink_callback *cb,
-                              int *t_p, int s_t)
+                              int *t_p, int s_t, bool recur)
 {
        struct Qdisc *q;
        int b;
@@ -2168,7 +2168,7 @@ static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
        if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
                return -1;
 
-       if (!qdisc_dev(root))
+       if (!qdisc_dev(root) || !recur)
                return 0;
 
        if (tcm->tcm_parent) {
@@ -2203,13 +2203,13 @@ static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
        s_t = cb->args[0];
        t = 0;
 
-       if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
+       if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t, true) < 0)
                goto done;
 
        dev_queue = dev_ingress_queue(dev);
        if (dev_queue &&
            tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
-                               &t, s_t) < 0)
+                               &t, s_t, false) < 0)
                goto done;
 
 done: