Subject: [PATCH] sfq: add dummy bind/unbind handles

From: Stephen Hemminger <[email-masked]>
Date: Fri, 6 Aug 2010 15:23:13 -0700

Applying a filter to an SFQ qdisc would cause null dereference
in tcf_bind_filter because although SFQ is classful it didn't
have all the necessary equipment.

Better alternative to changing tcf_bind API is to just fix
SFQ.  This should go to net-2.6 and stable.

Signed-off-by: Stephen Hemminger <[email-masked]>

--- a/net/sched/sch_sfq.c	2010-08-06 15:07:26.552820159 -0700
+++ b/net/sched/sch_sfq.c	2010-08-06 15:14:24.458287452 -0700
@@ -502,6 +502,10 @@ static unsigned long sfq_get(struct Qdis
 	return 0;
 }
 
+static void sfq_put(struct Qdisc *q, unsigned long cl)
+{
+}
+
 static struct tcf_proto **sfq_find_tcf(struct Qdisc *sch, unsigned long cl)
 {
 	struct sfq_sched_data *q = qdisc_priv(sch);
@@ -511,6 +515,12 @@ static struct tcf_proto **sfq_find_tcf(s
 	return &q->filter_list;
 }
 
+static unsigned long sfq_bind_tcf(struct Qdisc *sch, unsigned long parent,
+				  u32 cl)
+{
+	return 0;
+}
+
 static int sfq_dump_class(struct Qdisc *sch, unsigned long cl,
 			  struct sk_buff *skb, struct tcmsg *tcm)
 {
@@ -556,6 +566,8 @@ static void sfq_walk(struct Qdisc *sch, 
 static const struct Qdisc_class_ops sfq_class_ops = {
 	.get		=	sfq_get,
 	.tcf_chain	=	sfq_find_tcf,
+	.bind_tcf	=	sfq_bind_tcf,
+	.unbind_tcf	=	sfq_put,
 	.dump		=	sfq_dump_class,
 	.dump_stats	=	sfq_dump_class_stats,