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Message-ID: <1440397943.15510.2.camel@gmail.com>
Subject: Re: [PATCH] mkfs.ubifs: remove the check for UBIFS_MAX_LEB_SZ
From: Artem Bityutskiy <dedekind1@gmail.com>
Reply-To: dedekind1@gmail.com
To: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>,
 richard.weinberger@gmail.com,  computersforpeace@gmail.com
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Date: Mon, 24 Aug 2015 09:32:23 +0300
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On Mon, 2015-08-24 at 09:07 +0800, Dongsheng Yang wrote:
> On 08/18/2015 04:52 PM, Artem Bityutskiy wrote:
> > On Tue, 2015-08-18 at 12:52 +0800, Dongsheng Yang wrote:
> > > There is a commit 92ed6c0 to increase UBIFS_MAX_LEB_SZ
> > > to 2MiB. But recently, as the leb size become larger and
> > > larger, 2MiB is not a suitable limit any more.
> > > 
> > > Then remove this check in mkfs.ubifs
> > > 
> > > Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
> > > ---
> > > NOTE:
> > > 	I am not sure the reason why we have to
> > > limit the leb size in mkfs.ubifs. Because
> > > I did not find any reason for it, I send
> > > this patch out. It's very possible I am
> > > mising something.
> > 
> > Well, this is sanity check for the user input. If you accidentally
> > added few zeroes, we want to spot this and inform you, and you may
> > appreciate that we did not just created a bugus image for you.
> > That's
> > the idea.
> 
> Sorry, Artem, I was trying to understand it, but I did not got the
> point. Could you give me some more information about the idea? Maybe
> an example?

Well, this is defensive programming concept. Something goes wrong, due
to bad user input and/or a bug we get to this place with an bogus size.
This check catches it and errors out versus we just go forward,
generate a bugus image, which you then flash and find that things do
not work, and then spend your time for further investigations. Nothing
more than that.

Artem.