scsi: Revert "scsi: iscsi: Fix HW conn removal use after free"

This reverts commit c577ab7.

The invocation of iscsi_put_conn() in iscsi_iter_destory_conn_fn() is
used to free the initial reference counter of iscsi_cls_conn.  For
non-qla4xxx cases, the ->destroy_conn() callback (e.g.,
iscsi_conn_teardown) will call iscsi_remove_conn() and iscsi_put_conn()
to remove the connection from the children list of session and free the
connection at last.  However for qla4xxx, it is not the case. The
->destroy_conn() callback of qla4xxx will keep the connection in the
session conn_list and doesn't use iscsi_put_conn() to free the initial
reference counter. Therefore, it seems necessary to keep the
iscsi_put_conn() in the iscsi_iter_destroy_conn_fn(), otherwise, there
will be memory leak problem.

Link: https://lore.kernel.org/all/[email protected]/
Fixes: c577ab7 ("scsi: iscsi: Fix HW conn removal use after free")
Signed-off-by: Li Lingfeng <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Mike Christie <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Li Lingfeng

drivers/scsi/scsi_transport_iscsi.c

@@ -2143,6 +2143,8 @@ static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
 		return 0;
 
 	iscsi_remove_conn(iscsi_dev_to_conn(dev));
+	iscsi_put_conn(iscsi_dev_to_conn(dev));
+
 	return 0;
 }