netdev - Re: [PATCH net 0/2] udp: fix early demux for mcast packets

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] [day] [month] [year] [list]

Date:   Sun, 01 Oct 2017 03:56:48 +0100 (WEST)
From:   David Miller <davem@...emloft.net>
To:     pabeni@...hat.com
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH net 0/2] udp: fix early demux for mcast packets

From: Paolo Abeni <pabeni@...hat.com>
Date: Thu, 28 Sep 2017 15:51:35 +0200

> Currently the early demux callbacks do not perform source address validation.
> This is not an issue for TCP or UDP unicast, where the early demux
> is only allowed for connected sockets and the source address is validated
> for the first packet and never change.
> 
> The UDP protocol currently allows early demux also for unconnected multicast
> sockets, and we are not currently doing any validation for them, after that
> the first packet lands on the socket: beyond ignoring the rp_filter - if 
> enabled - any kind of martian sources are also allowed.
> 
> This series addresses the issue allowing the early demux callback to return an
> error code, and performing the proper checks for unconnected UDP multicast
> sockets before leveraging the rx dst cache.
> 
> Alternatively we could disable the early demux for unconnected mcast sockets,
> but that would cause relevant performance regression - around 50% - while with
> this series, with full rp_filter in place, we keep the regression to a more 
> moderate level.

Series applied and queued up for -stable, thanks.