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Date: Wed, 13 Dec 2017 21:47:38 +0100
From: Boris Brezillon <boris.brezillon@free-electrons.com>
To: Colin Ian King <colin.king@canonical.com>
Cc: Richard Weinberger <richard@nod.at>,
        David Woodhouse <dwmw2@infradead.org>,
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        linux-mtd@lists.infradead.org, kernel-janitors@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH][mtd-next] mtd: nand: remove redundant check of len
Message-ID: <20171213214738.7ce39659@bbrezillon>
In-Reply-To: <e1038c1c-df3e-5a50-9332-616fdba6d165@canonical.com>
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On Wed, 13 Dec 2017 20:44:45 +0000
Colin Ian King <colin.king@canonical.com> wrote:

> On 13/12/17 20:38, Boris Brezillon wrote:
> > On Wed, 13 Dec 2017 20:30:04 +0000
> > Colin Ian King <colin.king@canonical.com> wrote:
> >   
> >> On 13/12/17 20:24, Boris Brezillon wrote:  
> >>> On Wed, 13 Dec 2017 20:17:43 +0000
> >>> Colin King <colin.king@canonical.com> wrote:
> >>>     
> >>>> From: Colin Ian King <colin.king@canonical.com>
> >>>>
> >>>> The check of len being zero is redundant as it has already been
> >>>> sanity checked for this value at the start of the function. Hence
> >>>> it is impossible for this test to be true and so the redundant
> >>>> code can be removed.    
> >>>
> >>> Nope, it's not the same test, the initial test is
> >>>
> >>> 	if (len && !buf)    
> >>
> >> Ah, the current tip from linux-next has:
> >>
> >> 1912        if (!len || !buf)
> >> 1913                return -EINVAL;
> >>
> >> ..so I guess that's why it got picked up by static analysis.  
> > 
> > Hm, that's weird, that's not what I see [1] in linux-next.  
> 
> I see my mistake, I fixed the *wrong* function, I'll send a v2. Doh.

Yep, just noticed that too. No need to send a patch though.