From: David Miller <davem@davemloft.net>
To: pabeni@redhat.com
Cc: netdev@vger.kernel.org, kuznet@ms2.inr.ac.ru,
sbohrer@rgmadvisors.com, hannes@stressinduktion.org
Subject: Re: [PATCH net] ipv4: fix broadcast packets reception
Date: Mon, 21 Mar 2016 11:50:09 -0400 (EDT) [thread overview]
Message-ID: <20160321.115009.1222014596215287583.davem@davemloft.net> (raw)
In-Reply-To: <b2a74da9e3b01065d0244088c2038c8b6ec1d334.1458574841.git.pabeni@redhat.com>
From: Paolo Abeni <pabeni@redhat.com>
Date: Mon, 21 Mar 2016 16:42:11 +0100
> Currently, ingress ipv4 broadcast datagrams are dropped if the
> ingress interface lacks an ipv4 address. This is caused by
> multiple issues:
>
> - in udp_v4_early_demux() ip_check_mc_rcu is invoked even on
> bcast packets
>
> - ip_route_input_slow() always try to validate the source
>
> This patch tries to address both issues, invoking ip_check_mc_rcu()
> only for mcast packets and calling fib_validate_source() only
> if the in_device has an address, at least.
>
> Fixes: 6e5403093261 ("ipv4/udp: Verify multicast group is ours in upd_v4_early_demux()")
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
I'm extremely weary to change the routing lookup code wrt. broadcast, multicast,
etc. policies, ever. The checks in there have multiple decades of precedence
and therefore are extremely dangerous to modify.
The UDP change in question didn't touch the generic routing code, therfore you
must fix this bug without modifying it either.
Sorry.
next prev parent reply other threads:[~2016-03-21 15:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-21 15:42 [PATCH net] ipv4: fix broadcast packets reception Paolo Abeni
2016-03-21 15:50 ` David Miller [this message]
2016-03-21 16:12 ` Paolo Abeni
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160321.115009.1222014596215287583.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=hannes@stressinduktion.org \
--cc=kuznet@ms2.inr.ac.ru \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=sbohrer@rgmadvisors.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox