[PATCH] md: Fix an unlock in an error path of lbs_store()

[Bart Van Assche <bvanassche@acm.org>]

If mddev_lock() fails, lbs_store() calls mddev_unlock() although the
reconfig_mutex is not held. Fix this by returning the mddev_lock() error
code directly. This bug has been detected by the Clang thread-safety
analyzer.

Fixes: 62ed1b582246 ("md: allow configuring logical block size")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/md/md.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index ac03b99f6428..7ce527073be9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6049,11 +6049,10 @@ lbs_store(struct mddev *mddev, const char *buf, size_t len)
 
 	err = mddev_lock(mddev);
 	if (err)
-		goto unlock;
+		return err;
 
 	err = mddev_set_logical_block_size(mddev, lbs);
 
-unlock:
 	mddev_unlock(mddev);
 	return err ?: len;
 }