dm: fix bug with RCU locking in dm_blk_report_zones

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@vger.kernel.org
Signed-off-by: Sergei Shtepa <sergei.shtepa@veeam.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 9b005e144014f0a234ae9e398a7d8bf6e384fbb3..95fcce30e2365605e9919404a353884045cd3678 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -491,8 +491,10 @@ static int dm_blk_report_zones(struct gendisk *disk, sector_t sector,
                return -EAGAIN;
 
        map = dm_get_live_table(md, &srcu_idx);
-       if (!map)
-               return -EIO;
+       if (!map) {
+               ret = -EIO;
+               goto out;
+       }
 
        do {
                struct dm_target *tgt;