[NETFILTER]: Properly use RCU in nf_ct_attach
Use rcu_assign_pointer/rcu_dereference for ip_ct_attach pointer instead
of self-made RCU and use rcu_read_lock to make sure the conntrack module
doesn't disappear below us while calling it, since this function can be
called from outside the netfilter hooks.
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 9b02ec4..59bcab1 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -1105,7 +1105,7 @@
{
int i;
- ip_ct_attach = NULL;
+ rcu_assign_pointer(ip_ct_attach, NULL);
/* This makes sure all current packets have passed through
netfilter framework. Roll on, two-stage module
@@ -1273,7 +1273,7 @@
write_unlock_bh(&nf_conntrack_lock);
/* For use by REJECT target */
- ip_ct_attach = __nf_conntrack_attach;
+ rcu_assign_pointer(ip_ct_attach, __nf_conntrack_attach);
/* Set up fake conntrack:
- to never be deleted, not in any hashes */