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Date: Thu, 25 Aug 2016 16:14:02 +0100
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>,
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Subject: Re: CVE-2014-9900 fix is not upstream
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> > I see someone did request it 2 years ago:
> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63479  
> 
> I don't think this is sufficient. Basically if you write one field in a
> struct after a memset again, the compiler is allowed by the standard to
> write padding bytes again, causing them to be undefined.

The question is simply what gcc actually does. The rest is C language
lawyering and since the kernel isn't written to the C language spec but
to gcc only gcc matters.

Alan