netdev - Re: [PATCH v2 net] l2tp: Allow duplicate session creation with UDP

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: <20200204.123940.1811238158618411613.davem@davemloft.net>
Date:   Tue, 04 Feb 2020 12:39:40 +0100 (CET)
From:   David Miller <davem@...emloft.net>
To:     ridge.kennedy@...iedtelesis.co.nz
Cc:     netdev@...r.kernel.org, gnault@...hat.com, tparkin@...alix.com,
        jchapman@...alix.com
Subject: Re: [PATCH v2 net] l2tp: Allow duplicate session creation with UDP

From: Ridge Kennedy <ridge.kennedy@...iedtelesis.co.nz>
Date: Tue,  4 Feb 2020 12:24:00 +1300

> In the past it was possible to create multiple L2TPv3 sessions with the
> same session id as long as the sessions belonged to different tunnels.
> The resulting sessions had issues when used with IP encapsulated tunnels,
> but worked fine with UDP encapsulated ones. Some applications began to
> rely on this behaviour to avoid having to negotiate unique session ids.
> 
> Some time ago a change was made to require session ids to be unique across
> all tunnels, breaking the applications making use of this "feature".
> 
> This change relaxes the duplicate session id check to allow duplicates
> if both of the colliding sessions belong to UDP encapsulated tunnels.
> 
> Fixes: dbdbc73b4478 ("l2tp: fix duplicate session creation")
> Signed-off-by: Ridge Kennedy <ridge.kennedy@...iedtelesis.co.nz>

Applied and queued up for -stable, thank you.