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Subject: Re: [PATCH 1/2] tpm/tpm_ppi: Do not compare strcmp(a,b) == -1
From: Joe Perches <joe@perches.com>
To: Peter Huewe <peterhuewe@gmx.de>
Cc: Ashley Lai <ashley@ashleylai.com>, Rajiv Andrade <mail@srajiv.net>,
	Marcel Selhorst <tpmdd@selhorst.net>,
	tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org,
	Xiaoyan Zhang <xiaoyan.zhang@intel.com>,
	Gang Wei <gang.wei@intel.com>, stable@vger.kernel.org
Date: Tue, 29 Oct 2013 18:05:44 -0700
In-Reply-To: <1383093628-31580-1-git-send-email-peterhuewe@gmx.de>
References: <1383093628-31580-1-git-send-email-peterhuewe@gmx.de>
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On Wed, 2013-10-30 at 01:40 +0100, Peter Huewe wrote:
> strcmp does return the difference between two strings not only -1,0,1
> consequently
>  if (strcmp (a,b) == -1)
> might lead to taking the wrong branch
> 
> -> compare with <= instead.

lib/string.c:strcmp returns only -1,0,1
so that's what the arch versions should do too.
However, arch implementations do vary...

fyi: using
	if (strcmp(foo, bar) < 0)
is canonical.

There are no existing <= -1 uses.