From 1fb9489bf190ce2b3fc03891f3de4b2d30600e28 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Wed, 8 Aug 2012 21:53:36 +0000 Subject: [PATCH] net: Loopback ifindex is constant now As pointed out, there are places, that access net->loopback_dev->ifindex and after ifindex generation is made per-net this value becomes constant equals 1. So go ahead and introduce the LOOPBACK_IFINDEX constant and use it where appropriate. Signed-off-by: Pavel Emelyanov Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/loopback.c | 1 + include/net/net_namespace.h | 7 +++++++ net/decnet/dn_route.c | 6 +++--- net/ipv4/fib_frontend.c | 2 +- net/ipv4/ipmr.c | 2 +- net/ipv4/netfilter/ipt_rpfilter.c | 2 +- net/ipv4/route.c | 6 +++--- net/ipv6/route.c | 2 +- 8 files changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index e2a06fd996d5..4a075babe193 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -197,6 +197,7 @@ static __net_init int loopback_net_init(struct net *net) if (err) goto out_free_netdev; + BUG_ON(dev->ifindex != LOOPBACK_IFINDEX); net->loopback_dev = dev; return 0; diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 6dc3db3466bf..97e441945c13 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -105,6 +105,13 @@ struct net { struct sock *diag_nlsk; }; +/* + * ifindex generation is per-net namespace, and loopback is + * always the 1st device in ns (see net_dev_init), thus any + * loopback device should get ifindex 1 + */ + +#define LOOPBACK_IFINDEX 1 #include diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c index 85a3604c87c8..c855e8d0738f 100644 --- a/net/decnet/dn_route.c +++ b/net/decnet/dn_route.c @@ -961,7 +961,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *o .saddr = oldflp->saddr, .flowidn_scope = RT_SCOPE_UNIVERSE, .flowidn_mark = oldflp->flowidn_mark, - .flowidn_iif = init_net.loopback_dev->ifindex, + .flowidn_iif = LOOPBACK_IFINDEX, .flowidn_oif = oldflp->flowidn_oif, }; struct dn_route *rt = NULL; @@ -979,7 +979,7 @@ static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *o "dn_route_output_slow: dst=%04x src=%04x mark=%d" " iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr), le16_to_cpu(oldflp->saddr), - oldflp->flowidn_mark, init_net.loopback_dev->ifindex, + oldflp->flowidn_mark, LOOPBACK_IFINDEX, oldflp->flowidn_oif); /* If we have an output interface, verify its a DECnet device */ @@ -1042,7 +1042,7 @@ source_ok: if (!fld.daddr) goto out; } - fld.flowidn_oif = init_net.loopback_dev->ifindex; + fld.flowidn_oif = LOOPBACK_IFINDEX; res.type = RTN_LOCAL; goto make_route; } diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index c43ae3fba792..7f073a38c87d 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -218,7 +218,7 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb) scope = RT_SCOPE_UNIVERSE; if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) { fl4.flowi4_oif = 0; - fl4.flowi4_iif = net->loopback_dev->ifindex; + fl4.flowi4_iif = LOOPBACK_IFINDEX; fl4.daddr = ip_hdr(skb)->saddr; fl4.saddr = 0; fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos); diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 8eec8f4a0536..3a57570c8ee5 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1798,7 +1798,7 @@ static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb) .flowi4_oif = (rt_is_output_route(rt) ? skb->dev->ifindex : 0), .flowi4_iif = (rt_is_output_route(rt) ? - net->loopback_dev->ifindex : + LOOPBACK_IFINDEX : skb->dev->ifindex), .flowi4_mark = skb->mark, }; diff --git a/net/ipv4/netfilter/ipt_rpfilter.c b/net/ipv4/netfilter/ipt_rpfilter.c index 31371be8174b..c30130062cd6 100644 --- a/net/ipv4/netfilter/ipt_rpfilter.c +++ b/net/ipv4/netfilter/ipt_rpfilter.c @@ -85,7 +85,7 @@ static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par) return ipv4_is_local_multicast(iph->daddr) ^ invert; flow.flowi4_iif = 0; } else { - flow.flowi4_iif = dev_net(par->in)->loopback_dev->ifindex; + flow.flowi4_iif = LOOPBACK_IFINDEX; } flow.daddr = iph->saddr; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 21ad369014c0..c58137391a3d 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1619,7 +1619,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, if (res.type == RTN_LOCAL) { err = fib_validate_source(skb, saddr, daddr, tos, - net->loopback_dev->ifindex, + LOOPBACK_IFINDEX, dev, in_dev, &itag); if (err < 0) goto martian_source_keep_err; @@ -1895,7 +1895,7 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4) orig_oif = fl4->flowi4_oif; - fl4->flowi4_iif = net->loopback_dev->ifindex; + fl4->flowi4_iif = LOOPBACK_IFINDEX; fl4->flowi4_tos = tos & IPTOS_RT_MASK; fl4->flowi4_scope = ((tos & RTO_ONLINK) ? RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); @@ -1984,7 +1984,7 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4) if (!fl4->daddr) fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); dev_out = net->loopback_dev; - fl4->flowi4_oif = net->loopback_dev->ifindex; + fl4->flowi4_oif = LOOPBACK_IFINDEX; res.type = RTN_LOCAL; flags |= RTCF_LOCAL; goto make_route; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 8e80fd279100..0ddf2d132e7f 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -965,7 +965,7 @@ struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk, { int flags = 0; - fl6->flowi6_iif = net->loopback_dev->ifindex; + fl6->flowi6_iif = LOOPBACK_IFINDEX; if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr)) flags |= RT6_LOOKUP_F_IFACE; -- 2.20.1