From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f71.google.com (mail-oi0-f71.google.com [209.85.218.71]) by kanga.kvack.org (Postfix) with ESMTP id DEEF66B02B4 for ; Tue, 29 Aug 2017 14:55:22 -0400 (EDT) Received: by mail-oi0-f71.google.com with SMTP id w10so5772006oie.1 for ; Tue, 29 Aug 2017 11:55:22 -0700 (PDT) Received: from mail-io0-x22d.google.com (mail-io0-x22d.google.com. [2607:f8b0:4001:c06::22d]) by mx.google.com with ESMTPS id x185si2745265oig.153.2017.08.29.11.55.22 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Aug 2017 11:55:22 -0700 (PDT) Received: by mail-io0-x22d.google.com with SMTP id k22so24575640iod.2 for ; Tue, 29 Aug 2017 11:55:22 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20170829081453.GA10196@infradead.org> References: <1503956111-36652-1-git-send-email-keescook@chromium.org> <1503956111-36652-16-git-send-email-keescook@chromium.org> <20170829081453.GA10196@infradead.org> From: Kees Cook Date: Tue, 29 Aug 2017 11:55:20 -0700 Message-ID: Subject: Re: [PATCH v2 15/30] xfs: Define usercopy region in xfs_inode slab cache Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig Cc: LKML , David Windsor , "Darrick J. Wong" , linux-xfs@vger.kernel.org, Linux-MM , "kernel-hardening@lists.openwall.com" On Tue, Aug 29, 2017 at 1:14 AM, Christoph Hellwig wrote: > One thing I've been wondering is wether we should actually just > get rid of the online area. Compared to reading an inode from > disk a single additional kmalloc is negligible, and not having the > inline data / extent list would allow us to reduce the inode size > significantly. > > Kees/David: how many of these patches are file systems with some > sort of inline data? Given that it's only about 30 patches declaring > allocations either entirely valid for user copy or not might end up > being nicer in many ways than these offsets. 9 filesystems use some form of inline data: xfs, vxfs, ufs, orangefs, exofs, befs, jfs, ext2, and ext4. How much of each slab is whitelisted varies by filesystem (e.g. ext2/4 uses i_data for other things, but ufs and orangefs and have a dedicate field for symlink names). -Kees -- Kees Cook Pixel Security -- 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