linux-kernel - Re: [PATCH 0/2] ppp: mppe: fixes MPPE desync on links which don't guarantee packet ordering

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, 26 Apr 2015 23:26:16 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	sylvain.rochet@...secur.com
Cc:	paulus@...ba.org, linux-ppp@...r.kernel.org,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 0/2] ppp: mppe: fixes MPPE desync on links which don't
 guarantee packet ordering

From: Sylvain Rochet <sylvain.rochet@...secur.com>
Date: Sun, 26 Apr 2015 20:40:51 +0200

> I am currently having an issue with PPP over L2TP (UDP) and MPPE in
> stateless mode (default mode), UDP does not guarantee packet ordering so
> we might get out of order packet. MPPE needs to be continuously synched
> so we should drop late UDP packet.
> 
> I added a printk on the number of time we rekeyed in MPPE decompressor,
> this is what we currently have if we receive a slightly out of order UDP
> packet:
 ...
> This is obviously wrong, we missed packet 1561 and we already rekeyed 2
> times for 1562 we previously received, we can't recover the decryption
> key we need for 1561, we should drop it instead of rekeying 4095 times.
> 
> This patch series drop any packet with are not within the 4096/2 forward
> window.

Series applied, thanks Sylvain.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/