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| author | Herbert Xu <herbert@gondor.apana.org.au> | 2014-10-05 12:00:22 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-10-07 15:12:44 -0400 |
| commit | 93fdd47e52f3f869a437319db9da1ea409acc07e (patch) | |
| tree | ff0bf4593b59fbe837bbe74f659e44cf5817db17 | |
| parent | 88b09a6d958af6c458acf055ee2eb5bc9564efda (diff) | |
| download | linux-93fdd47e52f3f869a437319db9da1ea409acc07e.tar.bz2 | |
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>
| -rw-r--r-- | net/bridge/br_netfilter.c | 11 | ||||
| -rw-r--r-- | net/bridge/br_private.h | 4 |
2 files changed, 15 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) ETH_HLEN-ETH_ALEN); /* tell br_dev_xmit to continue with forwarding */ nf_bridge->mask |= BRNF_BRIDGED_DNAT; + /* FIXME Need to refragment */ ret = neigh->output(neigh, skb); } neigh_release(neigh); @@ -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); diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index b6c04cbcfdc5..2398369c6dda 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -305,10 +305,14 @@ struct net_bridge struct br_input_skb_cb { struct net_device *brdev; + #ifdef CONFIG_BRIDGE_IGMP_SNOOPING int igmp; int mrouters_only; #endif + + u16 frag_max_size; + #ifdef CONFIG_BRIDGE_VLAN_FILTERING bool vlan_filtered; #endif |