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=-10.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 EEF7EC433E0 for ; Fri, 17 Jul 2020 08:24:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D11E42071A for ; Fri, 17 Jul 2020 08:24:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726335AbgGQIY3 convert rfc822-to-8bit (ORCPT ); Fri, 17 Jul 2020 04:24:29 -0400 Received: from relay6-d.mail.gandi.net ([217.70.183.198]:33755 "EHLO relay6-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725864AbgGQIY3 (ORCPT ); Fri, 17 Jul 2020 04:24:29 -0400 X-Originating-IP: 90.76.143.236 Received: from localhost (lfbn-tou-1-1075-236.w90-76.abo.wanadoo.fr [90.76.143.236]) (Authenticated sender: antoine.tenart@bootlin.com) by relay6-d.mail.gandi.net (Postfix) with ESMTPSA id EB990C000C; Fri, 17 Jul 2020 08:24:26 +0000 (UTC) Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT In-Reply-To: <7234E28B-C60F-4AB0-BCD9-4018B1A10B8D@dilger.ca> References: <20200701153404.1647002-1-antoine.tenart@bootlin.com> <7234E28B-C60F-4AB0-BCD9-4018B1A10B8D@dilger.ca> To: Andreas Dilger Cc: Ext4 Developers List , tytso@mit.edu, matthew.weber@rockwellcollins.com, thomas.petazzoni@bootlin.com Subject: Re: [PATCH] create_inode: set xattrs to the root directory as well From: Antoine Tenart Message-ID: <159497426579.3166.10315379148562462784@kwain> Date: Fri, 17 Jul 2020 10:24:25 +0200 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Hello Andreas, Quoting Andreas Dilger (2020-07-17 09:46:37) > On Jul 1, 2020, at 9:34 AM, Antoine Tenart wrote: > > > > __populate_fs do copy the xattrs for all files and directories, but the > > root directory is skipped and as a result its extended attributes aren't > > set. This is an issue when using mkfs to build a full system image that > > can be used with SElinux in enforcing mode without making any runtime > > fix at first boot. > > > > This patch adds logic to set the root directory's extended attributes. > > > > Signed-off-by: Antoine Tenart > > --- > > misc/create_inode.c | 24 +++++++++++++++++++++++- > > 1 file changed, 23 insertions(+), 1 deletion(-) > > > > diff --git a/misc/create_inode.c b/misc/create_inode.c > > index e8d1df6b55a5..0a6e4dc23d16 100644 > > --- a/misc/create_inode.c > > +++ b/misc/create_inode.c > > @@ -820,7 +820,29 @@ static errcode_t __populate_fs(ext2_filsys fs, ext2_ino_t parent_ino, > > > > for (i = 0; i < num_dents; free(dent[i]), i++) { > > name = dent[i]->d_name; > > - if ((!strcmp(name, ".")) || (!strcmp(name, ".."))) > > + if (!strcmp(name, ".")) { > > (style) despite what was previously in the code, I think it is clearer > to write "if (strcmp(name, ".") == 0)", because it doesn't read like > "if not string compare" since that incorrectly seems like the strings > are *not* matching. I kept what was done elsewhere in the function, but I agree with you, let's introduce clearer new code :) > > + retval = ext2fs_namei(fs, root, parent_ino, ".", &ino); > > + if (retval) { > > + com_err(name, retval, 0); > > + goto out; > > + } > > + > > + /* > > + * Take special care for the root directory, to copy its > > + * extended attributes. > > + */ > > + if (ino == root) { > > Rather than checking this for every directory, it would be more efficient > to copy the root xattrs only at the start of the copy in populate_fs2(), > before the tree walk has started. Something like: > > file_info.path_len = 0; > file_info.path_max_len = 255; > file_info.path = calloc(file_info.path_max_len, 1); > > + retval = set_inode_xattr(fs, parent_ino, source_dir); > + if (retval) { > + com_err(__func__, retval, > + _("while copying xattrs on root directory")); > + goto out; > + } > + > retval = __populate_fs(fs, parent_ino, source_dir, root, &hdlinks, > &file_info, fs_callbacks); > > That is an even less code added, which is always good. Thanks for the suggestion, I find it way better. I'll prepare a v2. Thanks for the review! Antoine -- Antoine Ténart, Bootlin Embedded Linux and Kernel engineering https://bootlin.com