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Date: Fri, 29 Nov 2013 14:59:59 +0400
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: jb <jb.1234abcd@gmail.com>
Subject: Re: [RFC] how to get the size of a malloc(9) block ?
Message-ID: <20131129105959.GF90895@FreeBSD.org>
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On Thu, Nov 28, 2013 at 03:13:53PM +0000, jb wrote:
j> > But I don't understand why you find ksize()/malloc_usable_size() dangerous.
j> > ...
j> 
j> The original crime is commited when *usable size* (an implementation detail)
j> is exported (leaked) to the caller.
j> To be blunt, when a caller requests memory of certain size, and its request is
j> satisfied, then it is not its business to learn details beyond that (and they
j> should not be offered as well).
j> The API should be sanitized, in kernel and user space.
j> Otherwise, all kind of charlatans will try to play hair-raising games with it.
j> If the caller wants to track the *requested size* programmatically, it is its
j> business to do it and it can be done very easily.

+1

This is kind of APIs that just shouldn't exist.

-- 
Totus tuus, Glebius.