From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
idr_remove needs external synchronization.
Fixes: 6e4df4c64881 ("nbd: reduce the nbd_index_mutex scope")
Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/block/nbd.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index c5e2b4cd697f..2c63372a31dd 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1774,7 +1774,9 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
return nbd;
out_free_idr:
+ mutex_lock(&nbd_index_mutex);
idr_remove(&nbd_index_idr, index);
+ mutex_unlock(&nbd_index_mutex);
out_free_tags:
blk_mq_free_tag_set(&nbd->tag_set);
out_free_nbd:
--
2.30.2
