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Message-ID: <19f34abd0808301234k3fae5572xdd8835827201f15@mail.gmail.com>
Date: Sat, 30 Aug 2008 21:34:21 +0200
From: "Vegard Nossum" <vegard.nossum@gmail.com>
To: "Cyrill Gorcunov" <gorcunov@gmail.com>
Subject: Re: buffer overflow in /proc/sys/sunrpc/transports
Cc: "Tom Tucker" <tom@opengridcomputing.com>, "Neil Brown" <neilb@suse.de>,
       "Chuck Lever" <chuck.lever@oracle.com>, "Greg Banks" <gnb@sgi.com>,
       "J. Bruce Fields" <bfields@citi.umich.edu>,
       linux-kernel@vger.kernel.org
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On Sat, Aug 30, 2008 at 9:21 PM, Cyrill Gorcunov <gorcunov@gmail.com> wrote:
> | Hm. I think this is wrong. Shouldn't we copy as many bytes as the user
> | indicated?
>
> Well, hard to say what user-space programmer is expecting from us.
> I mean - maybe he (reader) wants only part of results not the whole
> contents BUT by this way he never know what the whole conetnts would be
> until trying to read more (ie to check if there no more data from
> kernel side). What is preferred behaviour - i don't know :)

For any other file, read(1) + read(1) should be exactly equivalent to
a read(2). What's the difference here?

(Btw, thanks for the quick reply :-))


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036