Add support for PREROUTING rules with skb->dev set to the vrf device.
INPUT rules are already allowed. Provides symmetry with the output path
which allows POSTROUTING rules.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv6 source address selection needs to consider the real egress route.
Similar to IPv4 implement a get_saddr6 method which is called if
source address has not been set. The get_saddr6 method does a full
lookup which means pulling a route from the VRF FIB table and properly
considering linklocal/multicast destination addresses. Lookup failures
(eg., unreachable) then cause the source address selection to fail
which gets propagated back to the caller.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Attempting to delete a VRF device with a socket bound to it can stall:
unregister_netdevice: waiting for red to become free. Usage count = 1
The unregister is waiting for the dst to be released and with it
references to the vrf device. Similar to dst_ifdown switch the dst
dev to loopback on delete for all of the dst's for the vrf device
and release the references to the vrf device.
Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1. Default VRF devices to not having a qdisc (IFF_NO_QUEUE). Users
can add one as desired.
2. Disable adding a VLAN to a VRF device.
3. Enable offloads and hardware features similar to other logical
devices (e.g., dummy, veth)
Change provides a significant boost in TCP stream Tx performance,
from ~2,700 Mbps to ~18,100 Mbps and makes throughput close to the
performance without a VRF (18,500 Mbps). netperf TCP_STREAM benchmark
using qemu with virtio+vhost for the NICs
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv6 multicast and link-local addresses require special handling by the
VRF driver:
1. Rather than using the VRF device index and full FIB lookups,
packets to/from these addresses should use direct FIB lookups based on
the VRF device table.
2. fail sends/receives on a VRF device to/from a multicast address
(e.g, make ping6 ff02::1%<vrf> fail)
3. move the setting of the flow oif to the first dst lookup and revert
the change in icmpv6_echo_reply made in ca254490c8 ("net: Add VRF
support to IPv6 stack"). Linklocal/mcast addresses require use of the
skb->dev.
With this change connections into and out of a VRF enslaved device work
for multicast and link-local addresses work (icmp, tcp, and udp)
e.g.,
1. packets into VM with VRF config:
ping6 -c3 fe80::e0:f9ff:fe1c:b974%br1
ping6 -c3 ff02::1%br1
ssh -6 fe80::e0:f9ff:fe1c:b974%br1
2. packets going out a VRF enslaved device:
ping6 -c3 fe80::18f8:83ff:fe4b:7a2e%eth1
ping6 -c3 ff02::1%eth1
ssh -6 root@fe80::18f8:83ff:fe4b:7a2e%eth1
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow drivers to pass flow arg to functions where the arg is not const
and allow the driver to make updates as needed (eg., setting oif).
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Frank Kellermann reported a kernel crash with 4.5.0 when IPv6 is
disabled at boot using the kernel option ipv6.disable=1. Using
current net-next with the boot option:
$ ip link add red type vrf table 1001
Generates:
[12210.919584] BUG: unable to handle kernel NULL pointer dereference at 0000000000000748
[12210.921341] IP: [<ffffffff814b30e3>] fib6_get_table+0x2c/0x5a
[12210.922537] PGD b79e3067 PUD bb32b067 PMD 0
[12210.923479] Oops: 0000 [#1] SMP
[12210.924001] Modules linked in: ipvlan 8021q garp mrp stp llc
[12210.925130] CPU: 3 PID: 1177 Comm: ip Not tainted 4.7.0-rc1+ #235
[12210.926168] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[12210.928065] task: ffff8800b9ac4640 ti: ffff8800bacac000 task.ti: ffff8800bacac000
[12210.929328] RIP: 0010:[<ffffffff814b30e3>] [<ffffffff814b30e3>] fib6_get_table+0x2c/0x5a
[12210.930697] RSP: 0018:ffff8800bacaf888 EFLAGS: 00010202
[12210.931563] RAX: 0000000000000748 RBX: ffffffff81a9e280 RCX: ffff8800b9ac4e28
[12210.932688] RDX: 00000000000000e9 RSI: 0000000000000002 RDI: 0000000000000286
[12210.933820] RBP: ffff8800bacaf898 R08: ffff8800b9ac4df0 R09: 000000000052001b
[12210.934941] R10: 00000000657c0000 R11: 000000000000c649 R12: 00000000000003e9
[12210.936032] R13: 00000000000003e9 R14: ffff8800bace7800 R15: ffff8800bb3ec000
[12210.937103] FS: 00007faa1766c700(0000) GS:ffff88013ac00000(0000) knlGS:0000000000000000
[12210.938321] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[12210.939166] CR2: 0000000000000748 CR3: 00000000b79d6000 CR4: 00000000000406e0
[12210.940278] Stack:
[12210.940603] ffff8800bb3ec000 ffffffff81a9e280 ffff8800bacaf8c8 ffffffff814b3135
[12210.941818] ffff8800bb3ec000 ffffffff81a9e280 ffffffff81a9e280 ffff8800bace7800
[12210.943040] ffff8800bacaf8f0 ffffffff81397c88 ffff8800bb3ec000 ffffffff81a9e280
[12210.944288] Call Trace:
[12210.944688] [<ffffffff814b3135>] fib6_new_table+0x24/0x8a
[12210.945516] [<ffffffff81397c88>] vrf_dev_init+0xd4/0x162
[12210.946328] [<ffffffff814091e1>] register_netdevice+0x100/0x396
[12210.947209] [<ffffffff8139823d>] vrf_newlink+0x40/0xb3
[12210.948001] [<ffffffff814187f0>] rtnl_newlink+0x5d3/0x6d5
...
The problem above is due to the fact that the fib hash table is not
allocated when IPv6 is disabled at boot.
As for the VRF driver it should not do any IPv6 initializations if IPv6
is disabled, so it needs to know if IPv6 is disabled at boot. The disable
parameter is private to the IPv6 module, so provide an accessor for
modules to determine if IPv6 was disabled at boot time.
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case a qdisc is used on a vrf device, we need to use different
lockdep classes to avoid false positives.
Use the new netdev_lockdep_set_classes() generic helper.
Reported-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add l3mdev rule per address family when the first VRF device is
created. The rules are installed with a default preference of 1000.
Users can replace the default rule as desired.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for locally originated traffic to VRF-local IPv6 addresses.
Similar to IPv4 a local dst is set on the skb and the packet is
reinserted with a call to netif_rx. With this patch, ping, tcp and udp
packets to a local IPv6 address are successfully routed:
$ ip addr show dev eth1
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
valid_lft forever preferred_lft forever
inet6 2100:1::1/120 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
valid_lft forever preferred_lft forever
$ ping6 -c1 -I red 2100:1::1
ping6: Warning: source address might be selected on device other than red.
PING 2100:1::1(2100:1::1) from 2100:1::1 red: 56 data bytes
64 bytes from 2100:1::1: icmp_seq=1 ttl=64 time=0.098 ms
ip6_input is exported so the VRF driver can use it for the dst input
function. The dst_alloc function for IPv4 defaults to setting the input and
output functions; IPv6's does not. VRF does not need to duplicate the Rx path
so just export the ipv6 input function.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for locally originated traffic to VRF-local addresses. If
destination device for an skb is the loopback or VRF device then set
its dst to a local version of the VRF cached dst_entry and call netif_rx
to insert the packet onto the rx queue - similar to what is done for
loopback. This patch handles IPv4 support; follow on patch handles IPv6.
With this patch, ping, tcp and udp packets to a local IPv4 address are
successfully routed:
$ ip addr show dev eth1
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
valid_lft forever preferred_lft forever
inet6 2100:1::1/120 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
valid_lft forever preferred_lft forever
$ ping -c1 -I red 10.100.1.1
ping: Warning: source address might be selected on device other than red.
PING 10.100.1.1 (10.100.1.1) from 10.100.1.1 red: 56(84) bytes of data.
64 bytes from 10.100.1.1: icmp_seq=1 ttl=64 time=0.057 ms
This patch also enables use of IPv4 loopback address on the VRF device:
$ ip addr add dev red 127.0.0.1/8
$ ping -c1 -I red 127.0.0.1
PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 red: 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.058 ms
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the stripping of the ethernet header from is_ip_tx_frame into the
ipv4 and ipv6 outbound functions and collapse vrf_send_v4_prep into
vrf_process_v4_outbound.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 2fb7ea455d.
It results in build errors because ip6_input is not a
symbol exported to modules.
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for locally originated traffic to VRF-local IPv6 addresses.
Similar to IPv4 a local dst is set on the skb and the packet is
reinserted with a call to netif_rx. With this patch, ping, tcp and udp
packets to a local IPv6 address are successfully routed:
$ ip addr show dev eth1
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
valid_lft forever preferred_lft forever
inet6 2100:1::1/120 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
valid_lft forever preferred_lft forever
$ ping6 -c1 -I red 2100:1::1
ping6: Warning: source address might be selected on device other than red.
PING 2100:1::1(2100:1::1) from 2100:1::1 red: 56 data bytes
64 bytes from 2100:1::1: icmp_seq=1 ttl=64 time=0.098 ms
ip6_input is exported so the VRF driver can use it for the dst input
function. The dst_alloc function for IPv4 defaults to setting the input and
output functions; IPv6's does not. VRF does not need to duplicate the Rx path
so just export the ipv6 input function.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for locally originated traffic to VRF-local addresses. If
destination device for an skb is the loopback or VRF device then set
its dst to a local version of the VRF cached dst_entry and call netif_rx
to insert the packet onto the rx queue - similar to what is done for
loopback. This patch handles IPv4 support; follow on patch handles IPv6.
With this patch, ping, tcp and udp packets to a local IPv4 address are
successfully routed:
$ ip addr show dev eth1
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master red state UP group default qlen 1000
link/ether 02:e0:f9:1c:b9:74 brd ff:ff:ff:ff:ff:ff
inet 10.100.1.1/24 brd 10.100.1.255 scope global eth1
valid_lft forever preferred_lft forever
inet6 2100:1::1/120 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe1c:b974/64 scope link
valid_lft forever preferred_lft forever
$ ping -c1 -I red 10.100.1.1
ping: Warning: source address might be selected on device other than red.
PING 10.100.1.1 (10.100.1.1) from 10.100.1.1 red: 56(84) bytes of data.
64 bytes from 10.100.1.1: icmp_seq=1 ttl=64 time=0.057 ms
This patch also enables use of IPv4 loopback address on the VRF device:
$ ip addr add dev red 127.0.0.1/8
$ ping -c1 -I red 127.0.0.1
PING 127.0.0.1 (127.0.0.1) from 127.0.0.1 red: 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.058 ms
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the stripping of the ethernet header from is_ip_tx_frame into the
ipv4 and ipv6 outbound functions. If the packet is destined to a local
address the header is retained since the packet is sent back to netif_rx.
Collapse vrf_send_v4_prep into vrf_process_v4_outbound.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VRF device exists to define L3 domains and guide FIB lookups. As
such its operstate is not relevant. Seeing 'state UNKNOWN' in the
output of 'ip link show' can be confusing, so set operstate at link
create.
Similarly, the MTU for a VRF device is not used; any fragmentation
of the payload is done on the output path based on the real egress
device. An MTU of 1500 on the VRF device while enslaved devices
have a higher MTU can lead to confusion. Since the VRF MTU is not
relevant set to 64k similar to what is done for loopback.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One cpu can be processing packets which includes using the cached route
entries in the vrf device's private data and on another cpu the device
gets deleted which releases the routes and sets the pointers in net_vrf
to NULL. This results in datapath dereferencing a NULL pointer.
Fix by protecting access to dst's with rcu.
Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the VRF driver uses the rx_handler to switch the skb device
to the VRF device. Switching the dev prior to the ip / ipv6 layer
means the VRF driver has to duplicate IP/IPv6 processing which adds
overhead and makes features such as retaining the ingress device index
more complicated than necessary.
This patch moves the hook to the L3 layer just after the first NF_HOOK
for PRE_ROUTING. This location makes exposing the original ingress device
trivial (next patch) and allows adding other NF_HOOKs to the VRF driver
in the future.
dev_queue_xmit_nit is exported so that the VRF driver can cycle the skb
with the switched device through the packet taps to maintain current
behavior (tcpdump can be used on either the vrf device or the enslaved
devices).
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow udp and raw sockets to send by oif that is an enslaved interface
versus the l3mdev/VRF device. For example, this allows BFD to use ifindex
from IP_PKTINFO on a receive to send a response without the need to
convert to the VRF index. It also allows ping and ping6 to work when
specifying an enslaved interface (e.g., ping -I swp1 <ip>) which is
a natural use case.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tables have to exist for VRFs to function. Ensure they exist
when VRF device is created.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vivek reported a kernel exception deleting a VRF with an active
connection through it. The root cause is that the socket has a cached
reference to a dst that is destroyed. Converting the dst_destroy to
dst_release and letting proper reference counting kick in does not
work as the dst has a reference to the device which needs to be released
as well.
I talked to Hannes about this at netdev and he pointed out the ipv4 and
ipv6 dst handling has dst_ifdown for just this scenario. Rather than
continuing with the reinvented dst wheel in VRF just remove it and
leverage the ipv4 and ipv6 versions.
Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Several cases of overlapping changes, as well as one instance
(vxlan) of a bug fix in 'net' overlapping with code movement
in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Nik pointed that the VRF driver should be using skb_header_pointer
instead of accessing skb->data and bits beyond directly which can
be garbage.
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allows userspace to have direct access to VRF table association
versus looking up master device and its table.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commands run in a vrf context are not failing as expected on a route lookup:
root@kenny:~# ip ro ls table vrf-red
unreachable default
root@kenny:~# ping -I vrf-red -c1 -w1 10.100.1.254
ping: Warning: source address might be selected on device other than vrf-red.
PING 10.100.1.254 (10.100.1.254) from 0.0.0.0 vrf-red: 56(84) bytes of data.
--- 10.100.1.254 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 999ms
Since the vrf table does not have a route for 10.100.1.254 the ping
should have failed. The saddr lookup causes a full VRF table lookup.
Propogating a lookup failure to the user allows the command to fail as
expected:
root@kenny:~# ping -I vrf-red -c1 -w1 10.100.1.254
connect: No route to host
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/renesas/ravb_main.c
kernel/bpf/syscall.c
net/ipv4/ipmr.c
All three conflicts were cases of overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Sometimes the drivers and other code would find it handy to know some
internal information about upper device being changed. So allow upper-code
to pass information down to notifier listeners during linking.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eliminate netdev_master_upper_dev_link_private and pass priv directly as
a parameter of netdev_master_upper_dev_link.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The private slave queue and slave struct haven't been used for anything
and aren't needed, this allows to reduce memory usage and simplify
enslave/release. We can use netdev_for_each_lower_dev() to free the vrf
ports when deleting a vrf device. Also if in the future a private struct
is needed for each slave, it can be implemented via lower devices'
private member (similar to how bonding does it).
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for IPv6 to VRF device driver. Implemenation parallels what
has been done for IPv4.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The network namespace is already passed into dst_output pass it into
dst->output lwt->output and friends.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is confusing and silly hiding a parameter so modify all of
the callers to pass in the appropriate socket or skb->sk if
no socket is known.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For consistency with the other similar methods in the kernel pass a
struct sock into the dst_ops .local_out method.
Simplifying the socket passing case is needed a prequel to passing a
struct net reference into .local_out.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add operation to l3mdev to lookup source address for a given flow.
Add support for the operation to VRF driver and convert existing
IPv4 hooks to use the new lookup.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv6 addrconf keys off of IFF_SLAVE so can not use it for L3 slave.
Add a new private flag and add netif_is_l3_slave function for checking
it.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move remaining structs to VRF driver and delete the vrf header file.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename IFF_VRF_MASTER to IFF_L3MDEV_MASTER and update the name of the
netif_is_vrf and netif_index_is_vrf macros.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/ipv4/arp.c
The net/ipv4/arp.c conflict was one commit adding a new
local variable while another commit was deleting one.
Signed-off-by: David S. Miller <davem@davemloft.net>
This is immediately motivated by the bridge code that chains functions that
call into netfilter. Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.
As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.
To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn. For the moment dst_output_okfn
just silently drops the struct net.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>