This is a note to let you know that I've just added the patch titled
ubi: Fix race condition between ubi volume creation and udev
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ubi-fix-race-condition-between-ubi-volume-creation-and-udev.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a51a0c8d213594bc094cb8e54aad0cb6d7f7b9a6 Mon Sep 17 00:00:00 2001
From: Clay McClure <clay@xxxxxxxxxxx>
Date: Thu, 21 Sep 2017 19:01:34 -0700
Subject: ubi: Fix race condition between ubi volume creation and udev
From: Clay McClure <clay@xxxxxxxxxxx>
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@xxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Richard Weinberger <richard@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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:
Patches currently in stable-queue which might be from clay@xxxxxxxxxxx are
queue-4.4/ubi-fix-race-condition-between-ubi-volume-creation-and-udev.patch