dm mpath: Add missing dm_put_device when failing to get scsi dh name

When commit fd81bc5 ("scsi: device_handler: Return error pointer in
scsi_dh_attached_handler_name()") added code to fail parsing the path if
scsi_dh_attached_handler_name() failed with -ENOMEM, it didn't clean up
the reference to the path device that had just been taken. Fix this, and
steamline the error paths of parse_path() a little.

Fixes: fd81bc5 ("scsi: device_handler: Return error pointer in scsi_dh_attached_handler_name()")
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

Author: bmarzins

drivers/md/dm-mpath.c

@@ -960,27 +960,27 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
 			attached_handler_name = NULL;
 		} else {
 			r = PTR_ERR(attached_handler_name);
-			goto bad;
+			ti->error = "error allocating handler name";
+			goto bad_put_device;
 		}
 	}
 	if (attached_handler_name || m->hw_handler_name) {
 		INIT_DELAYED_WORK(&p->activate_path, activate_path_work);
 		r = setup_scsi_dh(p->path.dev->bdev, m, &attached_handler_name, &ti->error);
 		kfree(attached_handler_name);
-		if (r) {
-			dm_put_device(ti, p->path.dev);
-			goto bad;
-		}
+		if (r)
+			goto bad_put_device;
 	}
 
 	r = ps->type->add_path(ps, &p->path, as->argc, as->argv, &ti->error);
-	if (r) {
-		dm_put_device(ti, p->path.dev);
-		goto bad;
-	}
+	if (r)
+		goto bad_put_device;
 
 	return p;
- bad:
+
+bad_put_device:
+	dm_put_device(ti, p->path.dev);
+bad:
 	free_pgpath(p);
 	return ERR_PTR(r);
 }