From patchwork Wed Feb 12 10:43:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 1236773 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ubuntu.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 48Hbqg3NbKz9s1x for ; Wed, 12 Feb 2020 21:44:31 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728280AbgBLKo3 (ORCPT ); Wed, 12 Feb 2020 05:44:29 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:52532 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725887AbgBLKnm (ORCPT ); Wed, 12 Feb 2020 05:43:42 -0500 Received: from ip5f5bf7ec.dynamic.kabel-deutschland.de ([95.91.247.236] helo=wittgenstein.fritz.box) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1j1pUZ-0005aC-Je; Wed, 12 Feb 2020 10:43:39 +0000 From: Christian Brauner To: "David S. Miller" , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: "Rafael J. Wysocki" , Pavel Machek , Jakub Kicinski , Eric Dumazet , Stephen Hemminger , linux-pm@vger.kernel.org, Christian Brauner Subject: [PATCH net-next 05/10] sysfs: add sysfs_change_owner() Date: Wed, 12 Feb 2020 11:43:16 +0100 Message-Id: <20200212104321.43570-6-christian.brauner@ubuntu.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200212104321.43570-1-christian.brauner@ubuntu.com> References: <20200212104321.43570-1-christian.brauner@ubuntu.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add a helper to change the owner of sysfs objects. The ownership of a sysfs object is determined based on the ownership of the corresponding kobject, i.e. only if the ownership of a kobject is changed will this function change the ownership of the corresponding sysfs entry. This function will be used to correctly account for kobject ownership changes, e.g. when moving network devices between network namespaces. Signed-off-by: Christian Brauner --- fs/sysfs/file.c | 35 +++++++++++++++++++++++++++++++++++ include/linux/sysfs.h | 6 ++++++ 2 files changed, 41 insertions(+) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 6239d9584f0b..6a0fe88061fd 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -642,3 +642,38 @@ int sysfs_file_change_owner(struct kobject *kobj, const char *name) return error; } EXPORT_SYMBOL_GPL(sysfs_file_change_owner); + +/** + * sysfs_change_owner - change owner of the given object. + * @kobj: object. + */ +int sysfs_change_owner(struct kobject *kobj) +{ + int error; + const struct kobj_type *ktype; + + if (!kobj->state_in_sysfs) + return -EINVAL; + + error = sysfs_file_change_owner(kobj, NULL); + if (error) + return error; + + ktype = get_ktype(kobj); + if (ktype) { + struct attribute **kattr; + + for (kattr = ktype->default_attrs; kattr && *kattr; kattr++) { + error = sysfs_file_change_owner(kobj, (*kattr)->name); + if (error) + return error; + } + + error = sysfs_groups_change_owner(kobj, ktype->default_groups); + if (error) + return error; + } + + return 0; +} +EXPORT_SYMBOL_GPL(sysfs_change_owner); diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 3b9770c5ecb7..b9ce60261e38 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -310,6 +310,7 @@ static inline void sysfs_enable_ns(struct kernfs_node *kn) return kernfs_enable_ns(kn); } +int sysfs_change_owner(struct kobject *kobj); int sysfs_file_change_owner(struct kobject *kobj, const char *name); int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ, const char *name); @@ -542,6 +543,11 @@ static inline int sysfs_link_change_owner(struct kobject *kobj, return 0; } +static inline int sysfs_change_owner(struct kobject *kobj) +{ + return 0; +} + static inline int sysfs_groups_change_owner(struct kobject *kobj, const struct attribute_group **groups) {