net_sched: convert tcindex to call tcf_exts_destroy from rcu callback
Adjust destroy path of cls_tcindex to call tcf_exts_destroy() after
rcu grace period.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index a557dba..944c8ff 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -27,6 +27,7 @@
struct tcindex_filter_result {
struct tcf_exts exts;
struct tcf_result res;
+ struct rcu_head rcu;
};
struct tcindex_filter {
@@ -133,8 +134,23 @@
return 0;
}
-static int
-tcindex_delete(struct tcf_proto *tp, unsigned long arg)
+static void tcindex_destroy_rexts(struct rcu_head *head)
+{
+ struct tcindex_filter_result *r;
+
+ r = container_of(head, struct tcindex_filter_result, rcu);
+ tcf_exts_destroy(&r->exts);
+}
+
+static void tcindex_destroy_fexts(struct rcu_head *head)
+{
+ struct tcindex_filter *f = container_of(head, struct tcindex_filter, rcu);
+
+ tcf_exts_destroy(&f->result.exts);
+ kfree(f);
+}
+
+static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
{
struct tcindex_data *p = rtnl_dereference(tp->root);
struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
@@ -162,9 +178,14 @@
rcu_assign_pointer(*walk, rtnl_dereference(f->next));
}
tcf_unbind_filter(tp, &r->res);
- tcf_exts_destroy(&r->exts);
+ /* all classifiers are required to call tcf_exts_destroy() after rcu
+ * grace period, since converted-to-rcu actions are relying on that
+ * in cleanup() callback
+ */
if (f)
- kfree_rcu(f, rcu);
+ call_rcu(&f->rcu, tcindex_destroy_fexts);
+ else
+ call_rcu(&r->rcu, tcindex_destroy_rexts);
return 0;
}