From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36222 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932706AbeCPP3k (ORCPT ); Fri, 16 Mar 2018 11:29:40 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Clay McClure , Richard Weinberger Subject: [PATCH 4.4 46/63] ubi: Fix race condition between ubi volume creation and udev Date: Fri, 16 Mar 2018 16:23:18 +0100 Message-Id: <20180316152304.810109748@linuxfoundation.org> In-Reply-To: <20180316152259.964532775@linuxfoundation.org> References: <20180316152259.964532775@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable 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 Cc: Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman --- 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 @@ -265,6 +265,12 @@ 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; @@ -304,11 +310,6 @@ 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); self_check_volumes(ubi); return err; @@ -328,6 +329,10 @@ 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: