ipvlan: fix bound dev checking for IPv6 l3s mode

The commit 59a0b022aa24 ("ipvlan: Make skb->skb_iif track skb->dev for l3s
mode") fixed ipvlan bonded dev checking by updating skb skb_iif. This fix
works for IPv4, as in raw_v4_input() the dif is from inet_iif(skb), which
is skb->skb_iif when there is no route.

But for IPv6, the fix is not enough, because in ipv6_raw_deliver() ->
raw_v6_match(), the dif is inet6_iif(skb), which is returns IP6CB(skb)->iif
instead of skb->skb_iif if it's not a l3_slave. To fix the IPv6 part
issue. Let's set IP6CB(skb)->iif to correct ifindex.

BTW, ipvlan handles NS/NA specifically. Since it works fine, I will not
reset IP6CB(skb)->iif when addr->atype is IPVL_ICMPV6.

Fixes: c675e06a98a4 ("ipvlan: decouple l3s mode dependencies from other modes")
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2196710
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipvlan: Make skb->skb_iif track skb->dev for l3s mode

For l3s mode, skb->dev is set to ipvlan interface in ipvlan_nf_input():
skb->dev = addr->master->dev
but, skb->skb_iif remain unchanged, this will cause socket lookup failed
if a target socket is bound to a interface, like the following example:

ip link add ipvlan0 link eth0 type ipvlan mode l3s
ip addr add dev ipvlan0 192.168.124.111/24
ip link set ipvlan0 up

ping -c 1 -I ipvlan0 8.8.8.8
100% packet loss

This is because there is no match sk in __raw_v4_lookup() as sk->sk_bound_dev_if != dif(skb->skb_iif).
Fix this by make skb->skb_iif track skb->dev in ipvlan_nf_input().

Fixes: c675e06a98a4 ("ipvlan: decouple l3s mode dependencies from other modes")
Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/29865b1f-6db7-c07a-de89-949d3721ea30@163.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipvlan: decouple l3s mode dependencies from other modes

Right now ipvlan has a hard dependency on CONFIG_NETFILTER and
otherwise it cannot be built. However, the only ipvlan operation
mode that actually depends on netfilter is l3s, everything else
is independent of it. Break this hard dependency such that users
are able to use ipvlan l3 mode on systems where netfilter is not
compiled in.

Therefore, this adds a hidden CONFIG_IPVLAN_L3S bool which is
defaulting to y when CONFIG_NETFILTER is set in order to retain
existing behavior for l3s. All l3s related code is refactored
into ipvlan_l3s.c that is compiled in when enabled.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Mahesh Bandewar <maheshb@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Martynas Pumputis <m@lambda.lt>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>