netdev - Re: [PATCH v2] net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)

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Date:   Mon, 2 Sep 2019 20:14:51 -0600
From:   David Ahern <dsahern@...il.com>
To:     Maciej Żenczykowski <zenczykowski@...il.com>,
        Maciej Żenczykowski <maze@...gle.com>,
        "David S . Miller" <davem@...emloft.net>
Cc:     netdev@...r.kernel.org, Lorenzo Colitti <lorenzo@...gle.com>
Subject: Re: [PATCH v2] net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128
 local route (and others)

On 9/2/19 10:23 AM, Maciej Żenczykowski wrote:
> From: Maciej Żenczykowski <maze@...gle.com>
> 
> There is a subtle change in behaviour introduced by:
>   commit c7a1ce397adacaf5d4bb2eab0a738b5f80dc3e43
>   'ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create'
> 
> Before that patch /proc/net/ipv6_route includes:
> 00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo
> 
> Afterwards /proc/net/ipv6_route includes:
> 00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80240001 lo
> 
> ie. the above commit causes the ::1/128 local (automatic) route to be flagged with RTF_ADDRCONF (0x040000).
> 
> AFAICT, this is incorrect since these routes are *not* coming from RA's.
> 
> As such, this patch restores the old behaviour.
> 
> Fixes: c7a1ce397adacaf5d4bb2eab0a738b5f80dc3e43
> Cc: David Ahern <dsahern@...il.com>
> Cc: Lorenzo Colitti <lorenzo@...gle.com>
> Signed-off-by: Maciej Żenczykowski <maze@...gle.com>
> ---
>  net/ipv6/route.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 

Looks correct to me. Thanks for the patch.

Reviewed-by: David Ahern <dsahern@...il.com>