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Date: Fri, 3 Aug 2007 08:47:56 +0530 (IST)
From: Satyam Sharma <satyam@infradead.org>
X-X-Sender: satyam@enigma.security.iitk.ac.in
To: Jan Engelhardt <jengelh@computergmbh.de>
cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>,
       linux-kernel@vger.kernel.org
Subject: Re: gcc fixed size char array initialization bug - known?
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On Thu, 2 Aug 2007, Jan Engelhardt wrote:

> On Aug 2 2007 21:55, Guennadi Liakhovetski wrote:
> > [...]
> >
> >	struct {
> >		char c[4];
> >		int i;
> >	} t;
> >	t.i = 0x12345678;
> >	strcpy(t.c, c);
> >
> >and t.i is silently corrupted. Just wanted to ask if this is known, 
> >really...
> 
> What does this have to do with the kernel? The string "0123" is
> generally _five_ characters long, so c[4] is not enough.
> Or use strncpy.

<nitpicking>

While we're talking of null-termination of strings, then I bet you
generally want to be using strlcpy(), really. Often strncpy() isn't
what you want. Of course, if that buffer isn't a string at all, then
you should be using memfoo() functions and not strbar() ones in the
first place ...
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