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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 729D0C6FD1D for ; Wed, 15 Mar 2023 12:30:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232468AbjCOMaT (ORCPT ); Wed, 15 Mar 2023 08:30:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232619AbjCOM3u (ORCPT ); Wed, 15 Mar 2023 08:29:50 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0D5251C87 for ; Wed, 15 Mar 2023 05:28:57 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 18CE1B81DFF for ; Wed, 15 Mar 2023 12:28:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 65CCBC433EF; Wed, 15 Mar 2023 12:28:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678883329; bh=0iM/cmRrXNdsjVn5KVYCdgr1QbuYLKPyPpLAslED/Lg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2cm0C8o/Ii41vCvxd5N6v6H227f5BoyHBnh+kFiwmGBZPx8fdEuyx6/vuZaQ0QDBA coJXcwW5ijCdKOOLdlJKoFcbReNnw4QJsEb5qprOY9l8wNQcNZyNo8hTz7bolwadgo +3K0W2QdEIWwvuRVhZszJSFuFrsUkKSW6t9y58Gc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Amir Goldstein , "Christian Brauner (Microsoft)" , Leah Rumancik , "Darrick J. Wong" , Sasha Levin Subject: [PATCH 5.15 101/145] fs: move should_remove_suid() Date: Wed, 15 Mar 2023 13:12:47 +0100 Message-Id: <20230315115742.305645082@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230315115738.951067403@linuxfoundation.org> References: <20230315115738.951067403@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Christian Brauner commit e243e3f94c804ecca9a8241b5babe28f35258ef4 upstream. Move the helper from inode.c to attr.c. This keeps the the core of the set{g,u}id stripping logic in one place when we add follow-up changes. It is the better place anyway, since should_remove_suid() returns ATTR_KILL_S{G,U}ID flags. Reviewed-by: Amir Goldstein Signed-off-by: Christian Brauner (Microsoft) Signed-off-by: Amir Goldstein Tested-by: Leah Rumancik Acked-by: Darrick J. Wong Signed-off-by: Sasha Levin --- fs/attr.c | 29 +++++++++++++++++++++++++++++ fs/inode.c | 29 ----------------------------- 2 files changed, 29 insertions(+), 29 deletions(-) diff --git a/fs/attr.c b/fs/attr.c index 686840aa91c8b..f045431bab1ad 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -20,6 +20,35 @@ #include "internal.h" +/* + * The logic we want is + * + * if suid or (sgid and xgrp) + * remove privs + */ +int should_remove_suid(struct dentry *dentry) +{ + umode_t mode = d_inode(dentry)->i_mode; + int kill = 0; + + /* suid always must be killed */ + if (unlikely(mode & S_ISUID)) + kill = ATTR_KILL_SUID; + + /* + * sgid without any exec bits is just a mandatory locking mark; leave + * it alone. If some exec bits are set, it's a real sgid; kill it. + */ + if (unlikely((mode & S_ISGID) && (mode & S_IXGRP))) + kill |= ATTR_KILL_SGID; + + if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode))) + return kill; + + return 0; +} +EXPORT_SYMBOL(should_remove_suid); + /** * chown_ok - verify permissions to chown inode * @mnt_userns: user namespace of the mount @inode was found from diff --git a/fs/inode.c b/fs/inode.c index a71fb82279bb1..3811269259e11 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1864,35 +1864,6 @@ void touch_atime(const struct path *path) } EXPORT_SYMBOL(touch_atime); -/* - * The logic we want is - * - * if suid or (sgid and xgrp) - * remove privs - */ -int should_remove_suid(struct dentry *dentry) -{ - umode_t mode = d_inode(dentry)->i_mode; - int kill = 0; - - /* suid always must be killed */ - if (unlikely(mode & S_ISUID)) - kill = ATTR_KILL_SUID; - - /* - * sgid without any exec bits is just a mandatory locking mark; leave - * it alone. If some exec bits are set, it's a real sgid; kill it. - */ - if (unlikely((mode & S_ISGID) && (mode & S_IXGRP))) - kill |= ATTR_KILL_SGID; - - if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode))) - return kill; - - return 0; -} -EXPORT_SYMBOL(should_remove_suid); - /* * Return mask of changes for notify_change() that need to be done as a * response to write or truncate. Return 0 if nothing has to be changed. -- 2.39.2