netdev - Re: [PATCH net-next 3/3] net: Add table id from route lookup to route response

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150902190836.GD20527@pox.localdomain>
Date:	Wed, 2 Sep 2015 21:08:36 +0200
From:	Thomas Graf <tgraf@...g.ch>
To:	David Ahern <dsa@...ulusnetworks.com>
Cc:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH net-next 3/3] net: Add table id from route lookup to
 route response

On 09/02/15 at 12:51pm, David Ahern wrote:
> On 9/2/15 12:49 PM, David Miller wrote:
> >From: Thomas Graf <tgraf@...g.ch>
> >Date: Wed, 2 Sep 2015 20:43:46 +0200
> >
> >>On 09/02/15 at 09:40am, David Ahern wrote:
> >>>rt_fill_info which is called for 'route get' requests hardcodes the
> >>>table id as RT_TABLE_MAIN which is not correct when multiple tables
> >>>are used. Use the newly added table id in the rtable to send back
> >>>the correct table.
> >>>
> >>>Signed-off-by: David Ahern <dsa@...ulusnetworks.com>
> >>
> >>What RTM_GETROUTE returns is not the actual route but a description
> >>of the routing decision which is why table id, scope, protocol, and
> >>prefix length are hardcoded. This is indicated by the RTM_F_CLONED
> >>flag. What you propose would break userspace ABI.
> >
> >Agreed, I don't think we can do this.
> >
> 
> Doesn't the table used to come up with the decision matter for IPv4? ie.,
> hardcoding to MAIN is misleading when there is absolutely no way the
> decision comes from that table. IPv6 already returns the table id.
> 
> Or is your response that it breaks ABI and hence not going to fix.

This behaviour comes back from when we still had the IPv4 routing cache
which was flat. I'm not against exposing the table id but you have
to use a new attribute for it.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html