netfilter: Pass struct net into the netfilter hooks
Pass a network namespace parameter into the netfilter hooks. At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.
This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".
In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.
The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume() xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont() ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont() ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc() sock_net(sk)
ipv6/ip6_output.c:ip6_xmit() sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb() dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc() sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev
In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)". I am documenting them in case something odd
pops up and someone starts trying to track down what happened.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index 03227ff..fefcd2e 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -573,8 +573,8 @@
ptr++;
cb->hops = *ptr++; /* Visit Count */
- return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, NULL, skb,
- skb->dev, NULL,
+ return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
+ &init_net, NULL, skb, skb->dev, NULL,
dn_route_rx_packet);
drop_it:
@@ -601,8 +601,8 @@
ptr += 2;
cb->hops = *ptr & 0x3f;
- return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, NULL, skb,
- skb->dev, NULL,
+ return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
+ &init_net, NULL, skb, skb->dev, NULL,
dn_route_rx_packet);
drop_it:
@@ -706,22 +706,22 @@
switch (flags & DN_RT_CNTL_MSK) {
case DN_RT_PKT_HELO:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
- NULL, skb, skb->dev, NULL,
+ &init_net, NULL, skb, skb->dev, NULL,
dn_route_ptp_hello);
case DN_RT_PKT_L1RT:
case DN_RT_PKT_L2RT:
return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
- NULL, skb, skb->dev, NULL,
+ &init_net, NULL, skb, skb->dev, NULL,
dn_route_discard);
case DN_RT_PKT_ERTH:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
- NULL, skb, skb->dev, NULL,
+ &init_net, NULL, skb, skb->dev, NULL,
dn_neigh_router_hello);
case DN_RT_PKT_EEDH:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
- NULL, skb, skb->dev, NULL,
+ &init_net, NULL, skb, skb->dev, NULL,
dn_neigh_endnode_hello);
}
} else {
@@ -770,8 +770,8 @@
cb->rt_flags |= DN_RT_F_IE;
cb->hops = 0;
- return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT, sk, skb,
- NULL, dev,
+ return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT,
+ &init_net, sk, skb, NULL, dev,
dn_to_neigh_output);
error:
@@ -819,8 +819,8 @@
if (rt->rt_flags & RTCF_DOREDIRECT)
cb->rt_flags |= DN_RT_F_IE;
- return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD, NULL, skb,
- dev, skb->dev,
+ return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD,
+ &init_net, NULL, skb, dev, skb->dev,
dn_to_neigh_output);
drop: