ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif
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)
[Backport of net-next 6a662719c9868b3d6c7d26b3a085f0cd3cc15e64]
Change-Id: Ib7a0a08d78c03800488afa1b2c170cb70e34cfd9
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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
diff --git a/include/net/flow.h b/include/net/flow.h
index c91e2aa..1426681f 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -12,6 +12,14 @@
#include <linux/atomic.h>
#include <linux/uidgid.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;
@@ -85,7 +93,7 @@
kuid_t uid)
{
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 b176978..b064d6d 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>
@@ -120,14 +121,6 @@
atomic_t rt_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 ea47f2f..4a7cf03 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -250,7 +250,7 @@
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 8f6cb7a..567285b 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -629,6 +629,7 @@
.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 49797ed0..c5b2c00 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -454,7 +454,7 @@
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 @@
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 2c84072..63cf7cd 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -701,7 +701,7 @@
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;
