| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.9 65/86] ubi: Fix race condition between ubi volume creation and udev | Date | Fri, 16 Mar 2018 16:23:28 +0100 |
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4.9-stable review patch. If anyone has any objections, please let me know.
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From: Clay McClure <clay@daemons.net>
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 <clay@daemons.net> Cc: <stable@vger.kernel.org> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- 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) ubi_eba_destroy_table(eba_tbl); out_acc:
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