From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id DE3E36B0292 for ; Tue, 20 Jun 2017 00:04:06 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id s65so119297605pfi.14 for ; Mon, 19 Jun 2017 21:04:06 -0700 (PDT) Received: from mail-pg0-x22c.google.com (mail-pg0-x22c.google.com. [2607:f8b0:400e:c05::22c]) by mx.google.com with ESMTPS id 3si1822801plr.637.2017.06.19.21.04.05 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Jun 2017 21:04:05 -0700 (PDT) Received: by mail-pg0-x22c.google.com with SMTP id 132so23695019pgb.2 for ; Mon, 19 Jun 2017 21:04:05 -0700 (PDT) Date: Mon, 19 Jun 2017 21:04:03 -0700 From: Eric Biggers Subject: Re: [kernel-hardening] [PATCH 21/23] usercopy: Restrict non-usercopy caches to size 0 Message-ID: <20170620040403.GA610@zzz.localdomain> References: <1497915397-93805-1-git-send-email-keescook@chromium.org> <1497915397-93805-22-git-send-email-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1497915397-93805-22-git-send-email-keescook@chromium.org> Sender: owner-linux-mm@kvack.org List-ID: To: Kees Cook Cc: kernel-hardening@lists.openwall.com, David Windsor , linux-mm@kvack.org, linux-kernel@vger.kernel.org Hi David + Kees, On Mon, Jun 19, 2017 at 04:36:35PM -0700, Kees Cook wrote: > With all known usercopied cache whitelists now defined in the kernel, switch > the default usercopy region of kmem_cache_create() to size 0. Any new caches > with usercopy regions will now need to use kmem_cache_create_usercopy() > instead of kmem_cache_create(). > While I'd certainly like to see the caches be whitelisted, it needs to be made very clear that it's being done (the cover letter for this series falsely claims that kmem_cache_create() is unchanged) and what the consequences are. Is there any specific plan for identifying caches that were missed? If it's expected for people to just fix them as they are found, then they need to be helped a little --- at the very least by putting a big comment above report_usercopy() that explains the possible reasons why the error might have triggered and what to do about it. - Eric -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org