path: root/net/bridge/br_netfilter.c
diff options
authorHerbert Xu <herbert@gondor.apana.org.au>2014-10-05 12:00:22 +0800
committerDavid S. Miller <davem@davemloft.net>2014-10-07 15:12:44 -0400
commit93fdd47e52f3f869a437319db9da1ea409acc07e (patch)
treeff0bf4593b59fbe837bbe74f659e44cf5817db17 /net/bridge/br_netfilter.c
parent3c59x: fix bad split of cpu_to_le32(pci_map_single()) (diff)
bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING
As we may defragment the packet in IPv4 PRE_ROUTING and refragment it after POST_ROUTING we should save the value of frag_max_size. This is still very wrong as the bridge is supposed to leave the packets intact, meaning that the right thing to do is to use the original frag_list for fragmentation. Unfortunately we don't currently guarantee that the frag_list is left untouched throughout netfilter so until this changes this is the best we can do. There is also a spot in FORWARD where it appears that we can forward a packet without going through fragmentation, mark it so that we can fix it later. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bridge/br_netfilter.c')
1 files changed, 11 insertions, 0 deletions
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index a615264cf01a..4063898cf8aa 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -404,6 +404,7 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
/* tell br_dev_xmit to continue with forwarding */
nf_bridge->mask |= BRNF_BRIDGED_DNAT;
+ /* FIXME Need to refragment */
ret = neigh->output(neigh, skb);
@@ -459,6 +460,10 @@ static int br_nf_pre_routing_finish(struct sk_buff *skb)
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
struct rtable *rt;
int err;
+ int frag_max_size;
+ frag_max_size = IPCB(skb)->frag_max_size;
+ BR_INPUT_SKB_CB(skb)->frag_max_size = frag_max_size;
if (nf_bridge->mask & BRNF_PKT_TYPE) {
skb->pkt_type = PACKET_OTHERHOST;
@@ -863,13 +868,19 @@ static unsigned int br_nf_forward_arp(const struct nf_hook_ops *ops,
static int br_nf_dev_queue_xmit(struct sk_buff *skb)
int ret;
+ int frag_max_size;
+ /* This is wrong! We should preserve the original fragment
+ * boundaries by preserving frag_list rather than refragmenting.
+ */
if (skb->protocol == htons(ETH_P_IP) &&
skb->len + nf_bridge_mtu_reduction(skb) > skb->dev->mtu &&
!skb_is_gso(skb)) {
+ frag_max_size = BR_INPUT_SKB_CB(skb)->frag_max_size;
if (br_parse_ip_options(skb))
/* Drop invalid packet */
return NF_DROP;
+ IPCB(skb)->frag_max_size = frag_max_size;
ret = ip_fragment(skb, br_dev_queue_push_xmit);
} else
ret = br_dev_queue_push_xmit(skb);