[Devel] [PATCH RH9 08/20] ve/kmod/whitelist: Enable vxlan module autoload from inside a Container

[Kirill Tkhai]

From: Pavel Tikhomirov <ptikhomirov at virtuozzo.com>

vxlan is safe in CT as:

1) Udp multicast socket to connect to outer word sits in creation net-
namespace, and these socket can get packets only forwarded/routed
in creation ns.

2) Vxlan device is owned by second netns(could be same as first) as
any other network device, so same all packets come to it are from
the same ns.

3) Vxlans logic works through vxlan_net placed on creation netns,
vxlan_fdb and vxlan_rdst are per vxlan device. Thus entries can
not intersec with entries from host and other CTs.

* One problem I can see now is adding fdb with ifindex(index of
device to route packets from UDP socket through) after vxlan is
moved to second namespace in vxlan_fdb_parse we use second
namespace to check ifindex by device lookup, but in
vxlan_xmit_one->ip_route_output_key->...->__ip_route_output_key
we use first(creation) namespace to lookup device and probably
will fail. So all fdb configuration should go before moving to
ns. Same is in mainstream AFAICS.

https://jira.sw.ru/browse/PSBM-53629

Signed-off-by: Pavel Tikhomirov <ptikhomirov at virtuozzo.com>
Acked-by: Andrei Vagin <avagin at virtuozzo.com>

khorenko@: Docker Swarm requires vxlans.

(cherry picked from vz7 commit
 d5805ee4d748 ("ve/net/vxlan: enable support and autoload in a container"))

Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
---
 kernel/kmod.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 9a24a65deecb..ddf44c79c851 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -261,6 +261,7 @@ static const char * const ve0_allowed_mod[] = {
 	"net-pf-16-proto-4-type-16",	/* PF_NETLINK, NETLINK_SOCK_DIAG, AF_NETLINK */
 
 	"rtnl-link-dummy",
+	"rtnl-link-vxlan",
 };
 
 /*