Date: Tue, 4 Mar 2008 09:13:20 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: hpa@zytor.com, tglx@linutronix.de, linux-kernel@vger.kernel.org,
       roland@redhat.com
Subject: Re: [patch] x86, i387: fix ptrace leakage using init_fpu()
Message-ID: <20080304081320.GA5689@elte.hu>
References: <20080303210108.GA28006@linux-os.sc.intel.com>
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* Suresh Siddha <suresh.b.siddha@intel.com> wrote:

> This bug is introduced by the recent i387 merge.
> 
> Current usage of unlazy_fpu() in ptrace specific routines is wrong. 
> unlazy_fpu() will not init fpu if the task never used math. So the 
> ptrace calls can expose the parent tasks FPU data in some cases.
> 
> Replace it with the init_fpu() which will init the math state, if the 
> task never used math before.

thanks Suresh, good catch! Applied to x86.git.

	Ingo
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