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Date:   Thu, 28 May 2020 20:17:12 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Ingo Molnar <mingo@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>
Subject: Re: [git pull] coredump infoleak fix
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On Thu, May 28, 2020 at 12:09:48PM -0700, Linus Torvalds wrote:
> On Thu, May 28, 2020 at 12:06 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
> >
> > It doesn't fix all problems, though - you don't get an infoleak, but
> > you do get incorrect data...
> 
> Oh, I'm not saying it should replace any fix to regset->get(). I'm
> just saying it is in addition to.
> 
> So if a regset has a reason to return less than the asked-for data, it
> can do so and there's no leak.

Might make sense to change the summary of that pull request to something
like
	make sure we don't forget to report the xstate components that happen
to be in init state - both for coredump and for PTRACE_GETREGSET