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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Sun, 13 Nov 2016 02:00:38 +0100
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To: Hannes Frederic Sowa <hannes@stressinduktion.org>
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Cc: David Ahern <dsa@cumulusnetworks.com>,
 YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>,
 LKML <linux-kernel@vger.kernel.org>,
 WireGuard mailing list <wireguard@lists.zx2c4.com>,
 Netdev <netdev@vger.kernel.org>
Subject: Re: [WireGuard] Source address fib invalidation on IPv6
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Hi Hannes,

On Sun, Nov 13, 2016 at 1:51 AM, Hannes Frederic Sowa
<hannes@stressinduktion.org> wrote:
> You probably need some combination of ipv6_chk_addr and/or
> ipv6_check_addr_and_flags (where dev can also be NULL). Be careful if a
> IFA_HOST or IFA_LINK address switches from one interface to another.

I can confirm this trick works beautifully:
https://git.zx2c4.com/WireGuard/commit/?id=eb65810fc6350c50b42abedd1291b12337d3dc3d

I'll see if I can fold this into the routing function so that it
behaves the same as v4, unless David gets there first.

Regards,
Jason