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From: Oliver Hartkopp <socketcan@hartkopp.net>
To: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: netdev@vger.kernel.org, security@kernel.org
Subject: Re: [SECURITY] CAN info leak/minor heap overflow
Date: Tue, 02 Nov 2010 21:16:54 +0100	[thread overview]
Message-ID: <4CD071B6.7030202@hartkopp.net> (raw)
In-Reply-To: <1288727605.2504.21.camel@dan>

On 02.11.2010 20:53, Dan Rosenberg wrote:
> 
>> Why is this bad? Can the addresses of CAN-BCM sock structs be used for
>> anything from userspace?
>>
>> For me they are just intended to be unique numbers ...
>>
> 
> This is a bad idea because it makes exploiting other kernel
> vulnerabilities easier.  Exposing the address of an object in a slab
> cache, especially an object that unprivileged users have some level of
> control of, is just an invitation to use that structure when writing
> exploits, for heap overflows or otherwise.

The "level of control of" is just creating a socket or not. None of the data
in the created struct can be influenced by an unprivileged user.
Btw. i can generally follow your concerns after this explanation.

I'm going to check the kernel src for other approaches to display unique
numbers in procfs and will send a patch that takes care.

Thanks,
Oliver

  parent reply	other threads:[~2010-11-02 20:17 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-11-02 18:28 [SECURITY] CAN info leak/minor heap overflow Dan Rosenberg
2010-11-02 19:43 ` Oliver Hartkopp
2010-11-02 19:53   ` Dan Rosenberg
2010-11-02 19:57     ` [Security] " Linus Torvalds
2010-11-02 20:19       ` Oliver Hartkopp
2010-11-02 20:16     ` Oliver Hartkopp [this message]
2010-11-05 18:33 ` [PATCH] Fix " Urs Thuermann
2010-11-09  7:52   ` Oliver Hartkopp
2010-11-09 17:05     ` David Miller
2010-11-10  6:52       ` Oliver Hartkopp
2010-11-10 17:51         ` David Miller
2010-11-10 22:10           ` Oliver Hartkopp

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