diff options
author | Mikulas Patocka <mpatocka@redhat.com> | 2014-11-05 22:00:13 (GMT) |
---|---|---|
committer | Mike Snitzer <snitzer@redhat.com> | 2014-11-13 01:15:04 (GMT) |
commit | 17181fb7a0c3a279196c0eeb2caba65a1519614b (patch) | |
tree | e8f9d8b7b2134f55e75fca41b9d4fa0165e2f088 /drivers/md/dm-thin.c | |
parent | d1d9220cbaeecce910f3ecfeb71cc897a678eb68 (diff) | |
download | linux-17181fb7a0c3a279196c0eeb2caba65a1519614b.tar.xz |
dm thin: fix a race in thin_dtr
As long as struct thin_c is in the list, anyone can grab a reference of
it. Consequently, we must wait for the reference count to drop to zero
*after* we remove the structure from the list, not before.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm-thin.c')
-rw-r--r-- | drivers/md/dm-thin.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 8c5504c..767417a 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -3622,14 +3622,14 @@ static void thin_dtr(struct dm_target *ti) struct thin_c *tc = ti->private; unsigned long flags; - thin_put(tc); - wait_for_completion(&tc->can_destroy); - spin_lock_irqsave(&tc->pool->lock, flags); list_del_rcu(&tc->list); spin_unlock_irqrestore(&tc->pool->lock, flags); synchronize_rcu(); + thin_put(tc); + wait_for_completion(&tc->can_destroy); + mutex_lock(&dm_thin_pool_table.mutex); __pool_dec(tc->pool); |