android_kernel_motorola_sm6225/net/l2tp
Guillaume Nault df90e68861 l2tp: fix lookup for sockets not bound to a device in l2tp_ip
When looking up an l2tp socket, we must consider a null netdevice id as
wild card. There are currently two problems caused by
__l2tp_ip_bind_lookup() not considering 'dif' as wild card when set to 0:

  * A socket bound to a device (i.e. with sk->sk_bound_dev_if != 0)
    never receives any packet. Since __l2tp_ip_bind_lookup() is called
    with dif == 0 in l2tp_ip_recv(), sk->sk_bound_dev_if is always
    different from 'dif' so the socket doesn't match.

  * Two sockets, one bound to a device but not the other, can be bound
    to the same address. If the first socket binding to the address is
    the one that is also bound to a device, the second socket can bind
    to the same address without __l2tp_ip_bind_lookup() noticing the
    overlap.

To fix this issue, we need to consider that any null device index, be
it 'sk->sk_bound_dev_if' or 'dif', matches with any other value.
We also need to pass the input device index to __l2tp_ip_bind_lookup()
on reception so that sockets bound to a device never receive packets
from other devices.

This patch fixes l2tp_ip6 in the same way.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30 14:14:08 -05:00
..
Kconfig l2tp: Call udp_sock_create 2014-07-14 16:12:15 -07:00
l2tp_core.c l2tp: fix use-after-free during module unload 2016-09-02 11:44:44 -07:00
l2tp_core.h l2tp: use IS_ENABLED() instead of checking for built-in or module 2016-09-10 21:19:11 -07:00
l2tp_debugfs.c ipv6: make lookups simpler and faster 2013-10-09 00:01:25 -04:00
l2tp_eth.c net: revert "net: l2tp: Treat NET_XMIT_CN as success in l2tp_eth_dev_xmit" 2016-11-23 20:18:36 -05:00
l2tp_ip.c l2tp: fix lookup for sockets not bound to a device in l2tp_ip 2016-11-30 14:14:08 -05:00
l2tp_ip6.c l2tp: fix lookup for sockets not bound to a device in l2tp_ip 2016-11-30 14:14:08 -05:00
l2tp_netlink.c l2tp: make nla_policy const 2016-09-01 14:09:01 -07:00
l2tp_ppp.c l2tp: use IS_ENABLED() instead of checking for built-in or module 2016-09-10 21:19:11 -07:00
Makefile l2tp: introduce L2TPv3 IP encapsulation support for IPv6 2012-05-01 09:30:55 -04:00