[PATCH 5.4 30/54] dm: fix bug with RCU locking in dm_blk_report_zones

[Greg Kroah-Hartman]

From: Sergei Shtepa <sergei.shtepa@xxxxxxxxx>

commit 89478335718c98557f10470a9bc5c555b9261c4e upstream.

The dm_get_live_table() function makes RCU read lock so
dm_put_live_table() must be called even if dm_table map is not found.

Fixes: e76239a3748c9 ("block: add a report_zones method")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sergei Shtepa <sergei.shtepa@xxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/md/dm.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -455,8 +455,10 @@ static int dm_blk_report_zones(struct ge
 		return -EAGAIN;
 
 	map = dm_get_live_table(md, &srcu_idx);
-	if (!map)
-		return -EIO;
+	if (!map) {
+		ret = -EIO;
+		goto out;
+	}
 
 	tgt = dm_table_find_target(map, sector);
 	if (!tgt) {