From patchwork Fri Feb 14 18:35:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 11383029 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 306A713A4 for ; Fri, 14 Feb 2020 18:38:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0E6A624649 for ; Fri, 14 Feb 2020 18:38:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730663AbgBNSiJ (ORCPT ); Fri, 14 Feb 2020 13:38:09 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:33722 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389468AbgBNSiJ (ORCPT ); Fri, 14 Feb 2020 13:38:09 -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 1j2fqd-0000uO-Bq; Fri, 14 Feb 2020 18:37:55 +0000 From: Christian Brauner To: =?utf-8?q?St=C3=A9phane_Graber?= , "Eric W. Biederman" , Aleksa Sarai , Jann Horn Cc: smbarber@chromium.org, Seth Forshee , Alexander Viro , Alexey Dobriyan , Serge Hallyn , James Morris , Kees Cook , Jonathan Corbet , Phil Estes , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, containers@lists.linux-foundation.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, Christian Brauner Subject: [PATCH v2 18/28] capability: privileged_wrt_inode_uidgid(): handle fsid mappings Date: Fri, 14 Feb 2020 19:35:44 +0100 Message-Id: <20200214183554.1133805-19-christian.brauner@ubuntu.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200214183554.1133805-1-christian.brauner@ubuntu.com> References: <20200214183554.1133805-1-christian.brauner@ubuntu.com> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Switch privileged_wrt_inode_uidgid() to lookup fsids in the fsid mappings. If no fsid mappings are setup the behavior is unchanged, i.e. fsids are looked up in the id mappings. Filesystems that share a superblock in all user namespaces they are mounted in will retain their old semantics even with the introduction of fsidmappings. Signed-off-by: Christian Brauner --- /* v2 */ unchanged --- kernel/capability.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/kernel/capability.c b/kernel/capability.c index 1444f3954d75..2b0c1dc992e2 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -19,6 +19,8 @@ #include #include #include +#include +#include /* * Leveraged for setting/resetting capabilities @@ -486,8 +488,12 @@ EXPORT_SYMBOL(file_ns_capable); */ bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode) { - return kuid_has_mapping(ns, inode->i_uid) && - kgid_has_mapping(ns, inode->i_gid); + if (is_userns_visible(inode->i_sb->s_iflags)) + return kuid_has_mapping(ns, inode->i_uid) && + kgid_has_mapping(ns, inode->i_gid); + + return kfsuid_has_mapping(ns, inode->i_uid) && + kfsgid_has_mapping(ns, inode->i_gid); } /**