[NETFILTER]: Fix connection tracking bug in 2.6.12

In 2.6.12 we started dropping the conntrack reference when a packet
leaves the IP layer. This broke connection tracking on a bridge,
because bridge-netfilter defers calling some NF_IP_* hooks to the bridge
layer for locally generated packets going out a bridge, where the
conntrack reference is no longer available. This patch keeps the
reference in this case as a temporary solution, long term we will
remove the defered hook calling. No attempt is made to drop the
reference in the bridge-code when it is no longer needed, tc actions
could already have sent the packet anywhere.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 8 insertions, 2 deletions

diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index 03ae4edddac3..2d52fee63a8c 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -844,7 +844,7 @@ static unsigned int ip_sabotage_out(unsigned int hook, struct sk_buff **pskb,
                  * doesn't use the bridge parent of the indev by using
                  * the BRNF_DONT_TAKE_PARENT mask. */
                 if (hook == NF_IP_FORWARD && nf_bridge->physindev == NULL) {
-                        nf_bridge->mask &= BRNF_DONT_TAKE_PARENT;
+                        nf_bridge->mask |= BRNF_DONT_TAKE_PARENT;
                         nf_bridge->physindev = (struct net_device *)in;
                 }
 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index ee07aec215a0..6ce5c3292f9f 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -188,7 +188,13 @@ static inline int ip_finish_output2(struct sk_buff *skb)
                 skb = skb2;
         }
 
-        nf_reset(skb);
+#ifdef CONFIG_BRIDGE_NETFILTER
+        /* bridge-netfilter defers calling some IP hooks to the bridge layer
+         * and still needs the conntrack reference.
+         */
+        if (skb->nf_bridge == NULL)
+#endif
+                nf_reset(skb);
 
         if (hh) {
                 int hh_alen;