From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752518AbeE3LIx (ORCPT ); Wed, 30 May 2018 07:08:53 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:60769 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752683AbeE3LHk (ORCPT ); Wed, 30 May 2018 07:07:40 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Clay McClure" , "Richard Weinberger" Date: Wed, 30 May 2018 11:52:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 053/153] ubi: Fix race condition between ubi volume creation and udev In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.102-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Clay McClure commit a51a0c8d213594bc094cb8e54aad0cb6d7f7b9a6 upstream. Similar to commit 714fb87e8bc0 ("ubi: Fix race condition between ubi device creation and udev"), we should make the volume active before registering it. Signed-off-by: Clay McClure Signed-off-by: Richard Weinberger [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/mtd/ubi/vmt.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -312,6 +312,12 @@ int ubi_create_volume(struct ubi_device vol->last_eb_bytes = vol->usable_leb_size; } + /* Make volume "available" before it becomes accessible via sysfs */ + spin_lock(&ubi->volumes_lock); + ubi->volumes[vol_id] = vol; + ubi->vol_count += 1; + spin_unlock(&ubi->volumes_lock); + /* Register character device for the volume */ cdev_init(&vol->cdev, &ubi_vol_cdev_operations); vol->cdev.owner = THIS_MODULE; @@ -354,11 +360,6 @@ int ubi_create_volume(struct ubi_device if (err) goto out_sysfs; - spin_lock(&ubi->volumes_lock); - ubi->volumes[vol_id] = vol; - ubi->vol_count += 1; - spin_unlock(&ubi->volumes_lock); - ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED); if (paranoid_check_volumes(ubi)) dbg_err("check failed while creating volume %d", vol_id); @@ -379,6 +380,10 @@ out_sysfs: out_cdev: cdev_del(&vol->cdev); out_mapping: + spin_lock(&ubi->volumes_lock); + ubi->volumes[vol_id] = NULL; + ubi->vol_count -= 1; + spin_unlock(&ubi->volumes_lock); if (do_free) kfree(vol->eba_tbl); out_acc: