linux-kernel - Problems Receiving UDP Broadcasts on Some Versions of Linux

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-next>] [day] [month] [year] [list]

Message-ID: <20100125072749.GG21419@analytic.cynic.net>
Date:	Mon, 25 Jan 2010 16:27:49 +0900
From:	Curt Sampson <cjs@...rling-software.com>
To:	linux-kernel@...r.kernel.org
Subject: Problems Receiving UDP Broadcasts on Some Versions of Linux

I'm posting this here because it smells as if it may be something
a where a kernel network code developer might just say, "oh yeah,
obviously your problem is this."

I'm not subscribed to this list, so please cc me on any replies. (The
Mail-followup-to header may do this automatically for you.)

The short summary is that on two very similar servers on the same
network, an application that listens for broadcast UDP packets on a
given port works fine on the Ubuntu 8.04/Linux 2.6.24-26-server box but
does not receive the packets on the Ubuntu 9.04/Linux 2.6.28-17-server
box. I have confirmed that tcpdump sees identical packets being received
on both hosts.

Did something change between these two kernel revisions that I need to
listen differently?

Full details, including sample code, are available at:

  http://stackoverflow.com/questions/2130563/udp-broadcast-reception-problems-with-ubuntu-9-04-but-not-8-04

Thanks for any help you can give me. Even if you're not sure, but have
clues I should consider following up, feel free to e-mail me. I'm
also happy to take pointers to kernel code I should read, if there's
enlightenment there.

cjs
-- 
Curt Sampson         <cjs@...ic.net>         +81 90 7737 2974
             http://www.starling-software.com
The power of accurate observation is commonly called cynicism
by those who have not got it.    --George Bernard Shaw
--
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/