From patchwork Tue Sep 5 06:46:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Guy Briggs X-Patchwork-Id: 9937883 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 28717601EB for ; Tue, 5 Sep 2017 06:47:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1AB5A288AE for ; Tue, 5 Sep 2017 06:47:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0C1DA288B1; Tue, 5 Sep 2017 06:47:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4560F288A7 for ; Tue, 5 Sep 2017 06:47:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750944AbdIEGq6 (ORCPT ); Tue, 5 Sep 2017 02:46:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45102 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750755AbdIEGq5 (ORCPT ); Tue, 5 Sep 2017 02:46:57 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5C91A65744; Tue, 5 Sep 2017 06:46:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 5C91A65744 Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=rgb@redhat.com Received: from madcap2.tricolour.ca (ovpn-112-9.rdu2.redhat.com [10.10.112.9]) by smtp.corp.redhat.com (Postfix) with ESMTP id A29A7955D1; Tue, 5 Sep 2017 06:46:54 +0000 (UTC) From: Richard Guy Briggs To: linux-security-module@vger.kernel.org, linux-audit@redhat.com Cc: Richard Guy Briggs , Andy Lutomirski , "Serge E. Hallyn" , Kees Cook , James Morris , Eric Paris , Paul Moore , Steve Grubb Subject: [PATCH V4 04/10] capabilities: use root_priveleged inline to clarify logic Date: Tue, 5 Sep 2017 02:46:04 -0400 Message-Id: In-Reply-To: References: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 05 Sep 2017 06:46:57 +0000 (UTC) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Introduce inline root_privileged() to make use of SECURE_NONROOT easier to read. Suggested-by: Serge Hallyn Signed-off-by: Richard Guy Briggs Reviewed-by: Serge Hallyn Acked-by: James Morris Acked-by: Kees Cook --- security/commoncap.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/security/commoncap.c b/security/commoncap.c index 623f251..1904f49 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -472,14 +472,14 @@ static int get_file_caps(struct linux_binprm *bprm, bool *effective, bool *has_f return rc; } +static inline bool root_privileged(void) { return !issecure(SECURE_NOROOT); } + static void handle_privileged_root(struct linux_binprm *bprm, bool has_fcap, bool *effective, kuid_t root_uid) { const struct cred *old = current_cred(); struct cred *new = bprm->cred; - if (issecure(SECURE_NOROOT)) - return; /* * If the legacy file capability is set, then don't set privs * for a setuid root binary run by a non-root user. Do set it @@ -536,7 +536,8 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) root_uid = make_kuid(new->user_ns, 0); - handle_privileged_root(bprm, has_fcap, &effective, root_uid); + if (root_privileged()) + handle_privileged_root(bprm, has_fcap, &effective, root_uid); /* if we have fs caps, clear dangerous personality flags */ if (__cap_gained(permitted, new, old)) @@ -602,7 +603,7 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (__cap_grew(effective, ambient, new)) { if (!__cap_full(effective, new) || !uid_eq(new->euid, root_uid) || !uid_eq(new->uid, root_uid) || - issecure(SECURE_NOROOT)) { + !root_privileged()) { ret = audit_log_bprm_fcaps(bprm, new, old); if (ret < 0) return ret;