linux-kernel - Re: [PATCH] fs, dlm: Don't leak, don't do pointless NULL checks and use kzalloc

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Message-ID: <alpine.LNX.2.00.1107021956290.16316@swampdragon.chaosbits.net>
Date:	Sat, 2 Jul 2011 19:57:10 +0200 (CEST)
From:	Jesper Juhl <jj@...osbits.net>
To:	David Teigland <teigland@...hat.com>
cc:	linux-kernel@...r.kernel.org, cluster-devel@...hat.com,
	Christine Caulfield <ccaulfie@...hat.com>
Subject: Re: [PATCH] fs, dlm: Don't leak, don't do pointless NULL checks and
 use kzalloc

On Wed, 29 Jun 2011, David Teigland wrote:

> On Wed, Jun 29, 2011 at 11:51:00PM +0200, Jesper Juhl wrote:
> > > I don't think so; num_nodes won't be set to zero.
> > 
> > Hmm. How so?  Maybe I'm missing something obvious, but;
> > num_nodes is initialized to zero at the beginning of the function, which 
> > means that we'll definately do the first allocation in the loop.
> 
> Zero is meant to mean "first time through the loop".
> 
> > We then set num_nodes equal to ls->ls_num_nodes - what guarantees that 
> > this will not be zero so we won't do a second allocation (and leak) the 
> > second time through the loop?
> 
> That's just the nature of a lockspace, I guess -- it doesn't make sense or
> exist without nodes in it.  I doubt any of the dlm code would work if that
> weren't true.
> 
Thank you for the explanation.

I've prepared a new patch with just the changes you ack'ed. I'll send it 
in a minute.

-- 
Jesper Juhl <jj@...osbits.net>       http://www.chaosbits.net/
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