diff options
| author | Pedro Tammela <pctammela@mojatatu.com> | 2023-07-28 18:35:33 +0300 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2023-08-01 11:47:24 +0300 |
| commit | 8798481b667fa7c9bbd5aa843bf1557ada699964 (patch) | |
| tree | 164b3ceb99342adfe3cfa8da837947ccfa784704 /net/sched/sch_qfq.c | |
| parent | 05e1d8bdb276068069d3de65e488700280029e20 (diff) | |
| download | linux-8798481b667fa7c9bbd5aa843bf1557ada699964.tar.xz | |
net/sched: wrap open coded Qdics class filter counter
The 'filter_cnt' counter is used to control a Qdisc class lifetime.
Each filter referecing this class by its id will eventually
increment/decrement this counter in their respective
'add/update/delete' routines.
As these operations are always serialized under rtnl lock, we don't
need an atomic type like 'refcount_t'.
It also means that we lose the overflow/underflow checks already
present in refcount_t, which are valuable to hunt down bugs
where the unsigned counter wraps around as it aids automated tools
like syzkaller to scream in such situations.
Wrap the open coded increment/decrement into helper functions and
add overflow checks to the operations.
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'net/sched/sch_qfq.c')
| -rw-r--r-- | net/sched/sch_qfq.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c index befaf74b33ca..7addc15f01b5 100644 --- a/net/sched/sch_qfq.c +++ b/net/sched/sch_qfq.c @@ -130,8 +130,6 @@ struct qfq_aggregate; struct qfq_class { struct Qdisc_class_common common; - unsigned int filter_cnt; - struct gnet_stats_basic_sync bstats; struct gnet_stats_queue qstats; struct net_rate_estimator __rcu *rate_est; @@ -545,7 +543,7 @@ static int qfq_delete_class(struct Qdisc *sch, unsigned long arg, struct qfq_sched *q = qdisc_priv(sch); struct qfq_class *cl = (struct qfq_class *)arg; - if (cl->filter_cnt > 0) + if (qdisc_class_in_use(&cl->common)) return -EBUSY; sch_tree_lock(sch); @@ -580,8 +578,8 @@ static unsigned long qfq_bind_tcf(struct Qdisc *sch, unsigned long parent, { struct qfq_class *cl = qfq_find_class(sch, classid); - if (cl != NULL) - cl->filter_cnt++; + if (cl) + qdisc_class_get(&cl->common); return (unsigned long)cl; } @@ -590,7 +588,7 @@ static void qfq_unbind_tcf(struct Qdisc *sch, unsigned long arg) { struct qfq_class *cl = (struct qfq_class *)arg; - cl->filter_cnt--; + qdisc_class_put(&cl->common); } static int qfq_graft_class(struct Qdisc *sch, unsigned long arg, |