From nobody Tue Jun 23 21:32:51 2026 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 04DD3C433F5 for ; Fri, 25 Feb 2022 20:34:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236599AbiBYUfG (ORCPT ); Fri, 25 Feb 2022 15:35:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231500AbiBYUfE (ORCPT ); Fri, 25 Feb 2022 15:35:04 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2466C1D8305 for ; Fri, 25 Feb 2022 12:34:31 -0800 (PST) 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 CFC6BB83359 for ; Fri, 25 Feb 2022 20:34:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E5DEBC340E7; Fri, 25 Feb 2022 20:34:27 +0000 (UTC) Date: Fri, 25 Feb 2022 15:34:26 -0500 From: Steven Rostedt To: LKML Cc: Al Viro Subject: [PATCH v3] tracefs: Set the group ownership in apply_options() not parse_options() Message-ID: <20220225153426.1c4cab6b@gandalf.local.home> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: "Steven Rostedt (Google)" Al Viro brought it to my attention that the dentries may not be filled when the parse_options() is called, causing the call to set_gid() to possibly crash. It should only be called if parse_options() succeeds totally anyway. He suggested the logical place to do the update is in apply_options(). Link: https://lore.kernel.org/all/20220225165219.737025658@goodmis.org/ Cc: stable@vger.kernel.org Reported-by: Al Viro Fixes: 48b27b6b5191 ("tracefs: Set all files to the same group ownership as= the mount option") Signed-off-by: Steven Rostedt (Google) --- fs/tracefs/inode.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index bafc02bf8220..de7252715b12 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -264,7 +264,6 @@ static int tracefs_parse_options(char *data, struct tra= cefs_mount_opts *opts) if (!gid_valid(gid)) return -EINVAL; opts->gid =3D gid; - set_gid(tracefs_mount->mnt_root, gid); break; case Opt_mode: if (match_octal(&args[0], &option)) @@ -291,7 +290,9 @@ static int tracefs_apply_options(struct super_block *sb) inode->i_mode |=3D opts->mode; =20 inode->i_uid =3D opts->uid; - inode->i_gid =3D opts->gid; + + /* Set all the group ids to the mount option */ + set_gid(sb->s_root, opts->gid); =20 return 0; } --=20 2.34.1