cls_route: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.
Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.
Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index 4b14ccd..ac9a5b8 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -257,13 +257,19 @@
return 0;
}
+static void __route4_delete_filter(struct route4_filter *f)
+{
+ tcf_exts_destroy(&f->exts);
+ tcf_exts_put_net(&f->exts);
+ kfree(f);
+}
+
static void route4_delete_filter_work(struct work_struct *work)
{
struct route4_filter *f = container_of(work, struct route4_filter, work);
rtnl_lock();
- tcf_exts_destroy(&f->exts);
- kfree(f);
+ __route4_delete_filter(f);
rtnl_unlock();
}
@@ -297,7 +303,10 @@
next = rtnl_dereference(f->next);
RCU_INIT_POINTER(b->ht[h2], next);
tcf_unbind_filter(tp, &f->res);
- call_rcu(&f->rcu, route4_delete_filter);
+ if (tcf_exts_get_net(&f->exts))
+ call_rcu(&f->rcu, route4_delete_filter);
+ else
+ __route4_delete_filter(f);
}
}
RCU_INIT_POINTER(head->table[h1], NULL);
@@ -338,6 +347,7 @@
/* Delete it */
tcf_unbind_filter(tp, &f->res);
+ tcf_exts_get_net(&f->exts);
call_rcu(&f->rcu, route4_delete_filter);
/* Strip RTNL protected tree */
@@ -541,6 +551,7 @@
*arg = f;
if (fold) {
tcf_unbind_filter(tp, &fold->res);
+ tcf_exts_get_net(&fold->exts);
call_rcu(&fold->rcu, route4_delete_filter);
}
return 0;
