From 6a662719c9868b3d6c7d26b3a085f0cd3cc15e64 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 15 Apr 2014 16:25:34 -0700 Subject: [PATCH] ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As suggested by Julian: Simply, flowi4_iif must not contain 0, it does not look logical to ignore all ip rules with specified iif. because in fib_rule_match() we do: if (rule->iifindex && (rule->iifindex != fl->flowi_iif)) goto out; flowi4_iif should be LOOPBACK_IFINDEX by default. We need to move LOOPBACK_IFINDEX to include/net/flow.h: 1) It is mostly used by flowi_iif 2) Fix the following compile error if we use it in flow.h by the patches latter: In file included from include/linux/netfilter.h:277:0, from include/net/netns/netfilter.h:5, from include/net/net_namespace.h:21, from include/linux/netdevice.h:43, from include/linux/icmpv6.h:12, from include/linux/ipv6.h:61, from include/net/ipv6.h:16, from include/linux/sunrpc/clnt.h:27, from include/linux/nfs_fs.h:30, from init/do_mounts.c:32: include/net/flow.h: In function ‘flowi4_init_output’: include/net/flow.h:84:32: error: ‘LOOPBACK_IFINDEX’ undeclared (first use in this function) Cc: Eric Biederman Cc: Julian Anastasov Cc: David S. Miller Signed-off-by: Cong Wang Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- include/net/flow.h | 10 +++++++++- include/net/net_namespace.h | 9 +-------- net/ipv4/fib_frontend.c | 2 +- net/ipv4/fib_semantics.c | 1 + net/ipv4/ipmr.c | 2 +- net/ipv4/netfilter/ipt_rpfilter.c | 5 +---- net/ipv6/ip6mr.c | 2 +- 7 files changed, 15 insertions(+), 16 deletions(-) diff --git a/include/net/flow.h b/include/net/flow.h index 64fd24836650..8109a159d1b3 100644 --- a/include/net/flow.h +++ b/include/net/flow.h @@ -11,6 +11,14 @@ #include #include +/* + * 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 + struct flowi_common { int flowic_oif; int flowic_iif; @@ -80,7 +88,7 @@ static inline void flowi4_init_output(struct flowi4 *fl4, int oif, __be16 dport, __be16 sport) { fl4->flowi4_oif = oif; - fl4->flowi4_iif = 0; + fl4->flowi4_iif = LOOPBACK_IFINDEX; fl4->flowi4_mark = mark; fl4->flowi4_tos = tos; fl4->flowi4_scope = scope; diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 79387f73f875..5f9eb260990f 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -9,6 +9,7 @@ #include #include +#include #include #include #include @@ -131,14 +132,6 @@ struct net { atomic_t fnhe_genid; }; -/* - * 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 /* Init's network namespace */ diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 1a629f870274..255aa9946fe7 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -250,7 +250,7 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, bool dev_match; fl4.flowi4_oif = 0; - fl4.flowi4_iif = oif; + fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX; fl4.daddr = src; fl4.saddr = dst; fl4.flowi4_tos = tos; diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index b53f0bf84dca..8a043f03c88e 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -631,6 +631,7 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, .daddr = nh->nh_gw, .flowi4_scope = cfg->fc_scope + 1, .flowi4_oif = nh->nh_oif, + .flowi4_iif = LOOPBACK_IFINDEX, }; /* It is not necessary, but requires a bit of thinking */ diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 28863570dd60..d84dc8d4c916 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -455,7 +455,7 @@ static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev) struct mr_table *mrt; struct flowi4 fl4 = { .flowi4_oif = dev->ifindex, - .flowi4_iif = skb->skb_iif, + .flowi4_iif = skb->skb_iif ? : LOOPBACK_IFINDEX, .flowi4_mark = skb->mark, }; int err; diff --git a/net/ipv4/netfilter/ipt_rpfilter.c b/net/ipv4/netfilter/ipt_rpfilter.c index c49dcd0284a0..4bfaedf9b34e 100644 --- a/net/ipv4/netfilter/ipt_rpfilter.c +++ b/net/ipv4/netfilter/ipt_rpfilter.c @@ -89,11 +89,8 @@ static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par) if (ipv4_is_multicast(iph->daddr)) { if (ipv4_is_zeronet(iph->saddr)) return ipv4_is_local_multicast(iph->daddr) ^ invert; - flow.flowi4_iif = 0; - } else { - flow.flowi4_iif = LOOPBACK_IFINDEX; } - + flow.flowi4_iif = LOOPBACK_IFINDEX; flow.daddr = iph->saddr; flow.saddr = rpfilter_get_saddr(iph->daddr); flow.flowi4_oif = 0; diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index 8737400af0a0..8659067da28e 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -700,7 +700,7 @@ static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct mr6_table *mrt; struct flowi6 fl6 = { .flowi6_oif = dev->ifindex, - .flowi6_iif = skb->skb_iif, + .flowi6_iif = skb->skb_iif ? : LOOPBACK_IFINDEX, .flowi6_mark = skb->mark, }; int err; -- GitLab