* [Patch net v2 1/2] ipv4,fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif
2014-04-15 23:25 [Patch net v2 0/2] ipv4: fix flowi4_iif for input routing Cong Wang
@ 2014-04-15 23:25 ` Cong Wang
2014-04-15 23:25 ` [Patch net v2 2/2] ipv4,route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source() Cong Wang
2014-04-16 5:42 ` [Patch net v2 0/2] ipv4: fix flowi4_iif for input routing Julian Anastasov
2 siblings, 0 replies; 5+ messages in thread
From: Cong Wang @ 2014-04-15 23:25 UTC (permalink / raw)
To: netdev
Cc: Cong Wang, Eric Biederman, Julian Anastasov, David S. Miller,
Cong Wang
From: Cong Wang <cwang@twopensource.com>
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 <ebiederm@xmission.com>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
---
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 64fd248..8109a15 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -11,6 +11,14 @@
#include <linux/in6.h>
#include <linux/atomic.h>
+/*
+ * 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 79387f7..5f9eb26 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -9,6 +9,7 @@
#include <linux/list.h>
#include <linux/sysctl.h>
+#include <net/flow.h>
#include <net/netns/core.h>
#include <net/netns/mib.h>
#include <net/netns/unix.h>
@@ -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 <linux/seq_file_net.h>
/* Init's network namespace */
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 1a629f8..255aa99 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 b53f0bf..8a043f0 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 2886357..d84dc8d 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 c49dcd0..4bfaedf 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 8737400..8659067 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;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Patch net v2 2/2] ipv4,route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source()
2014-04-15 23:25 [Patch net v2 0/2] ipv4: fix flowi4_iif for input routing Cong Wang
2014-04-15 23:25 ` [Patch net v2 1/2] ipv4,fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif Cong Wang
@ 2014-04-15 23:25 ` Cong Wang
2014-04-16 5:42 ` [Patch net v2 0/2] ipv4: fix flowi4_iif for input routing Julian Anastasov
2 siblings, 0 replies; 5+ messages in thread
From: Cong Wang @ 2014-04-15 23:25 UTC (permalink / raw)
To: netdev
Cc: Cong Wang, Eric Biederman, Julian Anastasov, David S. Miller,
Cong Wang
From: Cong Wang <cwang@twopensource.com>
In my special case, when a packet is redirected from veth0 to lo,
its skb->dev->ifindex would be LOOPBACK_IFINDEX. Meanwhile we
pass the hard-coded LOOPBACK_IFINDEX to fib_validate_source()
in ip_route_input_slow(). This would cause the following check
in fib_validate_source() fail:
(dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))
when rp_filter is disabeld on loopback. As suggested by Julian,
the caller should pass 0 here so that we will not end up by
calling __fib_validate_source().
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
---
net/ipv4/route.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 1485aaf..db1e0da 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1700,8 +1700,7 @@ 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,
- LOOPBACK_IFINDEX,
- dev, in_dev, &itag);
+ 0, dev, in_dev, &itag);
if (err < 0)
goto martian_source_keep_err;
goto local_input;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [Patch net v2 0/2] ipv4: fix flowi4_iif for input routing
2014-04-15 23:25 [Patch net v2 0/2] ipv4: fix flowi4_iif for input routing Cong Wang
2014-04-15 23:25 ` [Patch net v2 1/2] ipv4,fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif Cong Wang
2014-04-15 23:25 ` [Patch net v2 2/2] ipv4,route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source() Cong Wang
@ 2014-04-16 5:42 ` Julian Anastasov
2014-04-16 19:06 ` David Miller
2 siblings, 1 reply; 5+ messages in thread
From: Julian Anastasov @ 2014-04-16 5:42 UTC (permalink / raw)
To: Cong Wang; +Cc: netdev, Eric Biederman, David S. Miller, Cong Wang
Hello,
On Tue, 15 Apr 2014, Cong Wang wrote:
> This patchset fixes ->flowi4_iif for input routing and rp filter,
> based on suggestion from Julian. See per patch for details.
>
> v1 -> v2:
> * merge the first two patches into one
> * fix fib_check_nh() too
> * add this cover letter
>
> Cc: Eric Biederman <ebiederm@xmission.com>
> Cc: Julian Anastasov <ja@ssi.bg>
> Cc: David S. Miller <davem@davemloft.net>
> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
> Signed-off-by: Cong Wang <cwang@twopensource.com>
v2 looks good to me, thanks!
Reviewed-by: Julian Anastasov <ja@ssi.bg>
> Cong Wang (2):
> ipv4,fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif
> ipv4,route: pass 0 instead of LOOPBACK_IFINDEX to
> fib_validate_source()
>
> 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/ipv4/route.c | 3 +--
> net/ipv6/ip6mr.c | 2 +-
> 8 files changed, 16 insertions(+), 18 deletions(-)
>
> --
> 1.8.3.1
Regards
--
Julian Anastasov <ja@ssi.bg>
^ permalink raw reply [flat|nested] 5+ messages in thread