Close race in md_probe
There is a possible race in md_probe. If two threads call md_probe
for the same device, then one could exit (having checked that
->gendisk exists) before the other has called kobject_init_and_add,
thus returning an incomplete kobj which will cause problems when
we try to add children to it.
So extend the range of protection of disks_mutex slightly to
avoid this possibility.
Signed-off-by: Neil Brown <neilb@suse.de>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 2613227..9785209 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3359,9 +3359,9 @@
disk->queue = mddev->queue;
add_disk(disk);
mddev->gendisk = disk;
- mutex_unlock(&disks_mutex);
error = kobject_init_and_add(&mddev->kobj, &md_ktype, &disk->dev.kobj,
"%s", "md");
+ mutex_unlock(&disks_mutex);
if (error)
printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
disk->disk_name);