pkt_sched: Add some basic qdisc class ops verification. Was: [PATCH] sfq: add dummy...

Verify in register_qdisc() some basic qdisc class handlers are present.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index b9e8c3b7d406aacd9cc2319ddbffe0440cc6c311..8ed2f5649029f9086ee43a8cc6be26f9af36f650 100644 (file)
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -150,22 +150,34 @@ int register_qdisc(struct Qdisc_ops *qops)
        if (qops->enqueue == NULL)
                qops->enqueue = noop_qdisc_ops.enqueue;
        if (qops->peek == NULL) {
-               if (qops->dequeue == NULL) {
+               if (qops->dequeue == NULL)
                        qops->peek = noop_qdisc_ops.peek;
-               } else {
-                       rc = -EINVAL;
-                       goto out;
-               }
+               else
+                       goto out_einval;
        }
        if (qops->dequeue == NULL)
                qops->dequeue = noop_qdisc_ops.dequeue;
 
+       if (qops->cl_ops) {
+               const struct Qdisc_class_ops *cops = qops->cl_ops;
+
+               if (!(cops->get && cops->put))
+                       goto out_einval;
+
+               if (cops->tcf_chain && !(cops->bind_tcf && cops->unbind_tcf))
+                       goto out_einval;
+       }
+
        qops->next = NULL;
        *qp = qops;
        rc = 0;
 out:
        write_unlock(&qdisc_mod_lock);
        return rc;
+
+out_einval:
+       rc = -EINVAL;
+       goto out;
 }
 EXPORT_SYMBOL(register_qdisc);