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From: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
To: Axel Lin <axel.lin-8E1dMatC8ynQT0dZR+AlfA@public.gmane.org>
Cc: Wenyou Yang <wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>,
	linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH] spi: atmel: Fix test unsigned var < 0
Date: Wed, 26 Mar 2014 16:51:45 +0000	[thread overview]
Message-ID: <20140326165145.GD14287@sirena.org.uk> (raw)
In-Reply-To: <1395498809.16958.1.camel@phoenix>

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On Sat, Mar 22, 2014 at 10:33:29PM +0800, Axel Lin wrote:
> current_remaining_bytes is an unsigned long and cannot be below 0.

> -	if (xfer->bits_per_word > 8) {
> +
> +	if (xfer->bits_per_word > 8)
>  		as->current_remaining_bytes -= 2;
> -		if (as->current_remaining_bytes < 0)
> -			as->current_remaining_bytes = 0;
> -	} else {
> +	else
>  		as->current_remaining_bytes--;
> -	}

This removes an error check in the case that we set the remaining bytes
to -1.  The length validation the core does should ensure that never
happens but it seems wrong to just ignore that - we should at least note
in the changelog that the analysis has been done.

Are you sure that the best fix isn't to just use an int here?

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  reply	other threads:[~2014-03-26 16:51 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-03-22 14:33 [PATCH] spi: atmel: Fix test unsigned var < 0 Axel Lin
2014-03-26 16:51 ` Mark Brown [this message]
     [not found]   ` <20140326165145.GD14287-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-03-27  0:46     ` Axel Lin
     [not found]       ` <CAFRkauBh+4-NmneTh=io7grG4MpSZ98riybAOOpEff+KiPZUjg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-03-27  1:13         ` Yang, Wenyou
2014-03-27  1:23           ` Axel Lin

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