From d7b597421519d6f680eb8e152a0d8447466ee2d6 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 5 Jun 2015 13:27:13 +0200 Subject: netfilter: bridge: restore vlan tag when refragmenting If bridge netfilter is used with both bridge-nf-call-iptables and bridge-nf-filter-vlan-tagged enabled then ip fragments in VLAN frames are sent without the vlan header. This has never worked reliably. Turns out this relied on pre-3.5 behaviour where skb frag_list was used to store ip fragments; ip_fragment() then re-used these skbs. But since commit 3cc4949269e01f39443d0fcfffb5bc6b47878d45 ("ipv4: use skb coalescing in defragmentation") this is no longer the case. ip_do_fragment now needs to allocate new skbs, but these don't contain the vlan tag information anymore. Fix it by storing vlan information of the ressembled skb in the br netfilter percpu frag area, and restore them for each of the fragments. Fixes: 3cc4949269e01f3 ("ipv4: use skb coalescing in defragmentation") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/bridge/br_netfilter.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'net/bridge') diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 1e62ae5d8f4e..e4e5f2f29173 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -116,6 +116,8 @@ struct brnf_frag_data { char mac[NF_BRIDGE_MAX_MAC_HEADER_LENGTH]; u8 encap_size; u8 size; + u16 vlan_tci; + __be16 vlan_proto; }; static DEFINE_PER_CPU(struct brnf_frag_data, brnf_frag_data_storage); @@ -909,6 +911,11 @@ static int br_nf_push_frag_xmit(struct sock *sk, struct sk_buff *skb) return 0; } + if (data->vlan_tci) { + skb->vlan_tci = data->vlan_tci; + skb->vlan_proto = data->vlan_proto; + } + skb_copy_to_linear_data_offset(skb, -data->size, data->mac, data->size); __skb_push(skb, data->encap_size); @@ -972,6 +979,9 @@ static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb) nf_bridge_update_protocol(skb); data = this_cpu_ptr(&brnf_frag_data_storage); + + data->vlan_tci = skb->vlan_tci; + data->vlan_proto = skb->vlan_proto; data->encap_size = nf_bridge_encap_header_len(skb); data->size = ETH_HLEN + data->encap_size; -- cgit v1.2.3-59-g8ed1b