From: Davide Caratti dcaratti@redhat.com
[ Upstream commit 698285da79f5b0b099db15a37ac661ac408c80eb ]
taprio_graft() can insert a NULL element in the array of child qdiscs. As a consquence, taprio_reset() might not reset child qdiscs completely, and taprio_destroy() might leak resources. Fix it by ensuring that loops that iterate over q->qdiscs[] don't end when they find the first NULL item.
Fixes: 44d4775ca518 ("net/sched: sch_taprio: reset child qdiscs before freeing them") Fixes: 5a781ccbd19e ("tc: Add support for configuring the taprio scheduler") Suggested-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Davide Caratti dcaratti@redhat.com Link: https://lore.kernel.org/r/13edef6778fef03adc751582562fba4a13e06d6a.160824053... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sched/sch_taprio.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
--- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1604,8 +1604,9 @@ static void taprio_reset(struct Qdisc *s
hrtimer_cancel(&q->advance_timer); if (q->qdiscs) { - for (i = 0; i < dev->num_tx_queues && q->qdiscs[i]; i++) - qdisc_reset(q->qdiscs[i]); + for (i = 0; i < dev->num_tx_queues; i++) + if (q->qdiscs[i]) + qdisc_reset(q->qdiscs[i]); } sch->qstats.backlog = 0; sch->q.qlen = 0; @@ -1625,7 +1626,7 @@ static void taprio_destroy(struct Qdisc taprio_disable_offload(dev, q, NULL);
if (q->qdiscs) { - for (i = 0; i < dev->num_tx_queues && q->qdiscs[i]; i++) + for (i = 0; i < dev->num_tx_queues; i++) qdisc_put(q->qdiscs[i]);
kfree(q->qdiscs);