From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net: ipv6: Fix ping to link-local addresses.
Date: Mon, 08 Aug 2016 14:35:00 -0700 (PDT)
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From: Lorenzo Colitti <lorenzo@google.com>
Date: Mon,  8 Aug 2016 16:42:07 +0900

> ping_v6_sendmsg never sets flowi6_oif, so it is not possible to
> ping an IPv6 address on a different interface. Instead, it sets
> flowi6_iif, which is incorrect but harmless. Also, it returns an
> error if a passed-in scope ID doesn't match sk_bound_dev_if.
> 
> Get rid of the error, stop setting flowi6_iif, and support
> various ways of setting oif in the same priority order used by
> udpv6_sendmsg.
> 
> Tested: https://android-review.googlesource.com/#/c/254470/
> Signed-off-by: Lorenzo Colitti <lorenzo@google.com>

We should always give sk_bound_dev_if the highest priority.

Also, we should amend, not delete, the check against the scope
ID in the sockaddr.  As explained by YOSHIFUJI Hideaki.