[NETFILTER]: nf_conntrack: properly use RCU for nf_conntrack_destroyed callback
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index d59640e..0cc1505 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -318,6 +318,7 @@
struct nf_conn_help *help = nfct_help(ct);
struct nf_conntrack_l3proto *l3proto;
struct nf_conntrack_l4proto *l4proto;
+ typeof(nf_conntrack_destroyed) destroyed;
DEBUGP("destroy_conntrack(%p)\n", ct);
NF_CT_ASSERT(atomic_read(&nfct->use) == 0);
@@ -341,10 +342,12 @@
ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum);
if (l4proto && l4proto->destroy)
l4proto->destroy(ct);
- rcu_read_unlock();
- if (nf_conntrack_destroyed)
- nf_conntrack_destroyed(ct);
+ destroyed = rcu_dereference(nf_conntrack_destroyed);
+ if (destroyed)
+ destroyed(ct);
+
+ rcu_read_unlock();
write_lock_bh(&nf_conntrack_lock);
/* Expectations will have been removed in clean_from_lists,