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Date:   Mon, 18 Feb 2019 21:51:50 +0000
From:   Arthur Gautier <baloo@gandi.net>
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Jann Horn <jannh@google.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        kernel list <linux-kernel@vger.kernel.org>,
        Pascal Bouchareine <pascal@gandi.net>
Subject: Re: [PATCH] x86: uaccess: fix regression in unsafe_get_user
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On Mon, Feb 18, 2019 at 11:15:44AM -0800, Andy Lutomirski wrote:
> This seems like it's just papering over the underlying problem: with
> Jann's new checks in place, strncpy_from_user() is simply buggy.  Does
> the patch below look decent?  It's only compile-tested, but it's
> conceptually straightforward.  I was hoping I could get rid of the
> check-maximum-address stuff, but it's needed for architectures where
> the user range is adjacent to the kernel range (i.e. not x86_64).

I'm unable to trigger the BUG I had with my initramfs with this patch
applied. Thanks!

-- 
\o/ Arthur
 G  Gandi.net