netdev - Re: [PATCH v2] net: ipv6: Remove addresses for failures with strict DAD

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Date:   Mon, 22 Aug 2016 17:00:00 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     mmanning@...cade.com
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH v2] net: ipv6: Remove addresses for failures with
 strict DAD

From: Mike Manning <mmanning@...cade.com>
Date: Thu, 18 Aug 2016 14:39:40 +0100

> If DAD fails with accept_dad set to 2, global addresses and host routes
> are incorrectly left in place. Even though disable_ipv6 is set,
> contrary to documentation, the addresses are not dynamically deleted
> from the interface. It is only on a subsequent link down/up that these
> are removed. The fix is not only to set the disable_ipv6 flag, but
> also to call addrconf_ifdown(), which is the action to carry out when
> disabling IPv6. This results in the addresses and routes being deleted
> immediately. The DAD failure for the LL addr is determined as before
> via netlink, or by the absence of the LL addr (which also previously
> would have had to be checked for in case of an intervening link down
> and up). As the call to addrconf_ifdown() requires an rtnl lock, the
> logic to disable IPv6 when DAD fails is moved to addrconf_dad_work().
 ...
> Signed-off-by: Mike Manning <mmanning@...cade.com>

Applied, thanks.