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Date: Mon, 19 Dec 2011 17:19:32 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Robert Richter <robert.richter@amd.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        oprofile-list <oprofile-list@lists.sourceforge.net>
Subject: Re: [PATCH v2] oprofile: Fix uninitialized memory access when
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* Robert Richter <robert.richter@amd.com> wrote:

> On 19.12.11 15:17:03, Robert Richter wrote:
> > On 19.12.11 15:00:49, Ingo Molnar wrote:
> > 
> > > +	if (!count)
> > > +		return 0;
> > > +
> > >  	retval = oprofilefs_ulong_from_user(&value, buf, count);
> > >  	if (retval)
> > >  		return retval;
> > > 
> > > See the ugly and fragile pattern?
> > > 
> > > This should *really* be solved via the 
> > > oprofilefs_ulong_from_user() helper function, not by sprinkling 
> > > the !count checks in half a dozen places ...
> > 
> > Hmm, I thought there was no way to leave the code path with count == 0
> > and retval. But thinking about it it would be possible with returning
> > count or errors < 0. Will improve the patch.
> 
> Ingo, see my updated version below. [...]

Yeah, this looks a lot cleaner.

> [...] I am fine with appling it directly on tip/perf/urgent.

Applied,

Thanks,

	Ingo