Merge branch 'ipv6-sticky-pktinfo'

Paolo Abeni says:

====================
ipv6: fix sticky pktinfo behaviour

Currently:

ip addr add dev eth0 2001:0010::1/64
ip addr add dev eth1 2001:0020::1/64
ping6 -I eth0 2001:0020::2

do not lead to the expected results, i.e. eth1 is used as the
egress interface.

This is due to two related issues in handling sticky pktinfo,
used by ping6 to enforce the device binding:

- ip6_dst_lookup_flow()/ip6_dst_lookup_tail() do not really enforce
flowi6_oif match
- ipv6 udp connect() just ignore flowi6_oif

These patches address each issue individually.

The kernel has never enforced the egress interface specified
via the sticky pktinfo, except briefly between the commits
741a11d9 ("net: ipv6: Add RT6_LOOKUP_F_IFACE flag if oif is set")
and
d46a9d67 ("net: ipv6: Dont add RT6_LOOKUP_F_IFACE flag if saddr set"),
but the ping6 tools was unaffected up to iputils-20100214,
since before it used SO_BINDTODEVICE to enforce the egress
interface.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>