From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8D6EC3524D for ; Mon, 3 Feb 2020 17:38:51 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 194DC2080C for ; Mon, 3 Feb 2020 17:38:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Uh9wVVKd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 194DC2080C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17658-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 20418 invoked by uid 550); 3 Feb 2020 17:38:45 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 20395 invoked from network); 3 Feb 2020 17:38:44 -0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=+svzYeMjDifvnay5XBCjENPcDei37krIAEbCjdfWWhU=; b=Uh9wVVKd7GmAMVO4QoLCs33RIH tlUkrd456X1MQBI2ZcjKd8tWTxYKw/bt1d55Ecyox2OJeX/KE3bKnXvCj0vdsvzOSRJOd/UDIAj2w l69ejkcK5CyzMwzk0S4RHBdXLS04dd6+vaW8jfpHz5B4mBd/ZuzHl/qmllj4Q34oHizwWkUodym02 ZUMRhjFtl2ELh+OM+6mA5n82D1di9RosZqr2hOYtHgD5aGIXdOFNC+Vi54iDCsFS1U75qnFbhSdWd 6KQP4QlIfHfPrkzxQ8aWaj0dUQkgDa2J9kucmHTDPGk2LSzjnDt+zoORFqfTTcsUgOBgWXXrrmdLU rT5JVVNg==; Date: Mon, 3 Feb 2020 09:38:11 -0800 From: Christoph Hellwig To: Kees Cook Cc: Christian Borntraeger , Christoph Hellwig , Christopher Lameter , Jiri Slaby , Julian Wiedmann , Ursula Braun , Alexander Viro , linux-kernel@vger.kernel.org, David Windsor , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , linux-mm@kvack.org, linux-xfs@vger.kernel.org, Linus Torvalds , Andy Lutomirski , "David S. Miller" , Laura Abbott , Mark Rutland , "Martin K. Petersen" , Paolo Bonzini , Christoffer Dall , Dave Kleikamp , Jan Kara , Luis de Bethencourt , Marc Zyngier , Rik van Riel , Matthew Garrett , linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, kernel-hardening@lists.openwall.com, Vlastimil Babka , Michal Kubecek Subject: Re: [kernel-hardening] [PATCH 09/38] usercopy: Mark kmalloc caches as usercopy caches Message-ID: <20200203173811.GB30011@infradead.org> References: <201911141327.4DE6510@keescook> <202001271519.AA6ADEACF0@keescook> <5861936c-1fe1-4c44-d012-26efa0c8b6e7@de.ibm.com> <202001281457.FA11CC313A@keescook> <6844ea47-8e0e-4fb7-d86f-68046995a749@de.ibm.com> <20200129170939.GA4277@infradead.org> <771c5511-c5ab-3dd1-d938-5dbc40396daa@de.ibm.com> <202001300945.7D465B5F5@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202001300945.7D465B5F5@keescook> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Thu, Jan 30, 2020 at 11:23:38AM -0800, Kees Cook wrote: > Hm, looks like it's allocated from the low 16MB. Seems like poor naming! > :) There seems to be a LOT of stuff using GFP_DMA, and it seems unlikely > those are all expecting low addresses? Most of that is either completely or partially bogus. Besides the weird S/390 stuff pretty much everything should be using the dma allocators. A couple really messed up drivers even pass GFP_DMA* to the dma allocator, but my patches to fix that up seem to be stuck.