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From: ebiederm@xmission.com (Eric W. Biederman)
To: tim.gardner@canonical.com
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>,
	lamont@canonical.com, sconklin@canonical.com,
	netdev@vger.kernel.org
Subject: Re: Reported regression against commit a05d2ad
Date: Wed, 22 Jun 2011 11:00:56 -0700	[thread overview]
Message-ID: <m1y60tlp9j.fsf@fess.ebiederm.org> (raw)
In-Reply-To: <4E02273E.2080000@canonical.com> (Tim Gardner's message of "Wed, 22 Jun 2011 11:32:46 -0600")

Tim Gardner <tim.gardner@canonical.com> writes:

> On 06/21/2011 02:49 PM, Eric W. Biederman wrote:
> <snip>
>> I respectfully suggest that the bug is elsewhere perhaps a broken user
>> space application out there that needs to be fixed, or you have a kernel
>> memory stomp that removing patch a05d2ad happens to shift the memory
>> layout to be harmful in a different way.
>>
>
> OK, I'm remembering how PF_UNIX Unix domain sockets are used, so I think your
> theory about a misbehaving user space application is more likely. However, I am
> a bit confused about how an application can attempt to receive before the socket
> is fully opened. Some kind of race condition with socketpair() ?

The case that is relevant is a listening SOCK_SEQPACKET socket.

The case that is affected is when you call receive on a listening
socket.

It isn't that the socket isn't fully opened.  It is that accept is the
only legitimate operation at that point.

It took a mistake while someone was developing an application for this
kernel bug to be found.

Eric

      reply	other threads:[~2011-06-22 18:01 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-21 20:15 Reported regression against commit a05d2ad Herton Ronaldo Krzesinski
2011-06-21 20:38 ` Tim Gardner
2011-06-21 20:54   ` Eric W. Biederman
2011-06-21 20:49 ` Eric W. Biederman
2011-06-22 17:32   ` Tim Gardner
2011-06-22 18:00     ` Eric W. Biederman [this message]

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