xfrm: avoid creating temporary SA when there are no listeners
In the case when KMs have no listeners, km_query() will fail and
temporary SAs are garbage collected immediately after their allocation.
This causes strain on memory allocation, leading even to OOM since
temporary SA alloc/free cycle is performed for every packet
and garbage collection does not keep up the pace.
The sane thing to do is to make sure we have audience before
temporary SA allocation.
Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index afa5730..5313ccf 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -594,6 +594,7 @@
const struct xfrm_migrate *m,
int num_bundles,
const struct xfrm_kmaddress *k);
+ bool (*is_alive)(const struct km_event *c);
};
int xfrm_register_km(struct xfrm_mgr *km);
@@ -1646,6 +1647,20 @@
rcu_read_unlock();
return ret;
}
+
+static inline int xfrm_acquire_is_on(struct net *net)
+{
+ struct sock *nlsk;
+ int ret = 0;
+
+ rcu_read_lock();
+ nlsk = rcu_dereference(net->xfrm.nlsk);
+ if (nlsk)
+ ret = netlink_has_listeners(nlsk, XFRMNLGRP_ACQUIRE);
+ rcu_read_unlock();
+
+ return ret;
+}
#endif
static inline int xfrm_alg_len(const struct xfrm_algo *alg)