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Date: Sat, 7 Sep 2002 16:16:44 +0200
Subject: Re: [PATCH] POSIX message queues
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Cc: Ingo Molnar <mingo@elte.hu>, Amos Waterland <apw@us.ibm.com>,
       golbi@mat.uni.torun.pl, linux-kernel@vger.kernel.org
To: Pavel Machek <pavel@suse.cz>
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Am Freitag den, 6. September 2002, um 12:04, schrieb Pavel Machek:

> Hi!
>
>>> That is the fundamental problem with a userspace shared memory
>>> implementation: write permissions on a message queue should grant
>>> mq_send(), but write permissions on shared memory grant a lot more 
>>> than
>>> just that.
>>
>> is it really a problem? As long as the read and write queues are 
>> separated
>> per sender, all that can happen is that a sender is allowed to read his
>> own messages - that is not an exciting capability.
>
> Imagine something that writes data into the que then erases the data and
> gets rid of setuid.
>
Well, I can imagine that - but what do you mean by that?
Do you mean: replacing the data with shellcode, manipulating the length 
field
for provoking buffer overflows?

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