diff options
author | Vladimir Oltean <olteanv@gmail.com> | 2019-08-30 04:07:21 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2019-08-31 18:45:34 -0700 |
commit | efb55222d31c8c2af8b4ba42bb56b0b0beedf98e (patch) | |
tree | 86883eb68e11e1c388b8f418b2f1dc3d30894103 | |
parent | 5f81d5455589df2f580e634c2e9da55b80e63c30 (diff) |
taprio: Fix kernel panic in taprio_destroy
taprio_init may fail earlier than this line:
list_add(&q->taprio_list, &taprio_list);
i.e. due to the net device not being multi queue.
Attempting to remove q from the global taprio_list when it is not part
of it will result in a kernel panic.
Fix it by matching list_add and list_del better to one another in the
order of operations. This way we can keep the deletion unconditional
and with lower complexity - O(1).
Cc: Leandro Dorileo <leandro.maciel.dorileo@intel.com>
Fixes: 7b9eba7ba0c1 ("net/sched: taprio: fix picos_per_byte miscalculation")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/sched/sch_taprio.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index e25d414ae12f..8c85f61e98dd 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1249,6 +1249,10 @@ static int taprio_init(struct Qdisc *sch, struct nlattr *opt, */ q->clockid = -1; + spin_lock(&taprio_list_lock); + list_add(&q->taprio_list, &taprio_list); + spin_unlock(&taprio_list_lock); + if (sch->parent != TC_H_ROOT) return -EOPNOTSUPP; @@ -1266,10 +1270,6 @@ static int taprio_init(struct Qdisc *sch, struct nlattr *opt, if (!opt) return -EINVAL; - spin_lock(&taprio_list_lock); - list_add(&q->taprio_list, &taprio_list); - spin_unlock(&taprio_list_lock); - for (i = 0; i < dev->num_tx_queues; i++) { struct netdev_queue *dev_queue; struct Qdisc *qdisc; |