netdev - Re: [PATCH] LSM: Add post recvmsg() hook.

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]

Date:	Thu, 22 Jul 2010 10:22:51 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	penguin-kernel@...ove.SAKURA.ne.jp
Cc:	kuznet@....inr.ac.ru, pekkas@...core.fi, jmorris@...ei.org,
	yoshfuji@...ux-ipv6.org, kaber@...sh.net, paul.moore@...com,
	netdev@...r.kernel.org, linux-security-module@...r.kernel.org
Subject: Re: [PATCH] LSM: Add post recvmsg() hook.

From: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
Date: Thu, 22 Jul 2010 21:46:55 +0900

> David Miller wrote:
>> > Then, why does below proposal lose information?
>> 
>> Peek changes state, now it's possible that two processes end up
>> receiving the packet.
> 
> Indeed. We will need to protect sock->ops->recvmsg() call using a lock like

But this doesn't matter.

The fact is going to remain that you will be unable to return data
from recvmsg() to a blocking socket when ->poll() returns true even
though data is in fact there in the socket receive queue.

This is something that the existing LSM hooks do not do.

You can't create this silly situation where some packets in the socket
receive queue can be recvmsg()'d by some processes, but not by others.

At best, it is pure crazyness.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html