net/sched: fix ->get helper of the matchall cls

NicolasDichtel · davem330 · commit 0db6f8befc32 · 2019-04-01T14:13:25.000-07:00
It returned always NULL, thus it was never possible to get the filter. Example: $ ip link add foo type dummy $ ip link add bar type dummy $ tc qdisc add dev foo clsact $ tc filter add dev foo protocol all pref 1 ingress handle 1234 \ matchall action mirred ingress mirror dev bar Before the patch: $ tc filter get dev foo protocol all pref 1 ingress handle 1234 matchall Error: Specified filter handle not found. We have an error talking to the kernel After: $ tc filter get dev foo protocol all pref 1 ingress handle 1234 matchall filter ingress protocol all pref 1 matchall chain 0 handle 0x4d2 not_in_hw action order 1: mirred (Ingress Mirror to device bar) pipe index 1 ref 1 bind 1 CC: Yotam Gigi <yotamg@mellanox.com> CC: Jiri Pirko <jiri@mellanox.com> Fixes: fd62d9f ("net/sched: matchall: Fix configuration race") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_matchall.c b/net/sched/cls_matchall.c
@@ -130,6 +130,11 @@ static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
 
 static void *mall_get(struct tcf_proto *tp, u32 handle)
 {
+	struct cls_mall_head *head = rtnl_dereference(tp->root);
+
+	if (head && head->handle == handle)
+		return head;
+
 	return NULL;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -130,6 +130,11 @@ static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,`
`130`	`130`
`131`	`131`	`static void mall_get(struct tcf_proto tp, u32 handle)`
`132`	`132`	`{`
	`133`	`+ struct cls_mall_head *head = rtnl_dereference(tp->root);`
	`134`	`+`
	`135`	`+ if (head && head->handle == handle)`
	`136`	`+ return head;`
	`137`	`+`
`133`	`138`	`return NULL;`
`134`	`139`	`}`
`135`	`140`