Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 21 Sep 2021 12:01:12 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Stephen Kitt <steve@sk2.org>
Cc:     Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        James Morris <jmorris@namei.org>,
        "Serge E . Hallyn" <serge@hallyn.com>, linux-mm@kvack.org,
        linux-security-module@vger.kernel.org,
        linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH] mm: Remove HARDENED_USERCOPY_FALLBACK
Message-ID: <202109211200.14E421C@keescook>
References: <20210921061149.1091163-1-steve@sk2.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210921061149.1091163-1-steve@sk2.org>
Precedence: bulk

On Tue, Sep 21, 2021 at 08:11:49AM +0200, Stephen Kitt wrote:
> This has served its purpose and is no longer used. All usercopy
> violations appear to have been handled by now, any remaining
> instances (or new bugs) will cause copies to be rejected.
> 
> This isn't a direct revert of commit 2d891fbc3bb6 ("usercopy: Allow
> strict enforcement of whitelists"); since usercopy_fallback is
> effectively 0, the fallback handling is removed too.
> 
> This also removes the usercopy_fallback module parameter on
> slab_common.
> 
> Link: https://github.com/KSPP/linux/issues/153
> Signed-off-by: Stephen Kitt <steve@sk2.org>
> Suggested-by: Kees Cook <keescook@chromium.org>

Thanks for doing this!

Acked-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook