netfilter: ctnetlink: fix double helper assignation for NAT'ed conntracks
If we create a conntrack that has NAT handlings and a helper, the helper
is assigned twice. This happens because nf_nat_setup_info() - via
nf_conntrack_alter_reply() - sets the helper before ctnetlink, which
indeed does not check if the conntrack already has a helper as it thinks that
it is a brand new conntrack.
The fix moves the helper assignation before the set of the status flags.
This avoids a bogus assertion in __nf_ct_ext_add (if netfilter assertions are
enabled) which checks that the conntrack must not be confirmed.
This problem was introduced in 2.6.23 with the netfilter extension
infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 105a616..d1fb2f8 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -1136,25 +1136,6 @@
ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
ct->status |= IPS_CONFIRMED;
- if (cda[CTA_STATUS]) {
- err = ctnetlink_change_status(ct, cda);
- if (err < 0)
- goto err;
- }
-
- if (cda[CTA_PROTOINFO]) {
- err = ctnetlink_change_protoinfo(ct, cda);
- if (err < 0)
- goto err;
- }
-
- nf_ct_acct_ext_add(ct, GFP_KERNEL);
-
-#if defined(CONFIG_NF_CONNTRACK_MARK)
- if (cda[CTA_MARK])
- ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
-#endif
-
rcu_read_lock();
helper = __nf_ct_helper_find(rtuple);
if (helper) {
@@ -1168,6 +1149,29 @@
rcu_assign_pointer(help->helper, helper);
}
+ if (cda[CTA_STATUS]) {
+ err = ctnetlink_change_status(ct, cda);
+ if (err < 0) {
+ rcu_read_unlock();
+ goto err;
+ }
+ }
+
+ if (cda[CTA_PROTOINFO]) {
+ err = ctnetlink_change_protoinfo(ct, cda);
+ if (err < 0) {
+ rcu_read_unlock();
+ goto err;
+ }
+ }
+
+ nf_ct_acct_ext_add(ct, GFP_KERNEL);
+
+#if defined(CONFIG_NF_CONNTRACK_MARK)
+ if (cda[CTA_MARK])
+ ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
+#endif
+
/* setup master conntrack: this is a confirmed expectation */
if (master_ct) {
__set_bit(IPS_EXPECTED_BIT, &ct->status);
