From patchwork Fri Feb 14 18:35:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 11383099 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 57514159A for ; Fri, 14 Feb 2020 18:40:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37237222C2 for ; Fri, 14 Feb 2020 18:40:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730607AbgBNSkY (ORCPT ); Fri, 14 Feb 2020 13:40:24 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:33818 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729781AbgBNSkX (ORCPT ); Fri, 14 Feb 2020 13:40:23 -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 1j2fql-0000uO-JW; Fri, 14 Feb 2020 18:38:03 +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 24/28] commoncap: cap_task_fix_setuid(): handle fsid mappings Date: Fri, 14 Feb 2020 19:35:50 +0100 Message-Id: <20200214183554.1133805-25-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 cap_task_fix_setuid() 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. Signed-off-by: Christian Brauner --- /* v2 */ unchanged --- security/commoncap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/commoncap.c b/security/commoncap.c index 9641695d8383..0581c6aa8bdc 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -24,6 +24,7 @@ #include #include #include +#include /* * If a non-root user executes a setuid-root binary in @@ -1061,7 +1062,7 @@ int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags) * if not, we might be a bit too harsh here. */ if (!issecure(SECURE_NO_SETUID_FIXUP)) { - kuid_t root_uid = make_kuid(old->user_ns, 0); + kuid_t root_uid = make_kfsuid(old->user_ns, 0); if (uid_eq(old->fsuid, root_uid) && !uid_eq(new->fsuid, root_uid)) new->cap_effective = cap_drop_fs_set(new->cap_effective);