diff --git a/NEWS b/NEWS
index d3668344793..21ec4559f5b 100644
--- a/NEWS
+++ b/NEWS
@@ -53,6 +53,13 @@ included in the vX.Y.Z section and be denoted as:
    (** also appeared: A.B.C)  -- indicating that this item was previously
                                  included in release version vA.B.C.
 
+2.1.3 -- To be released
+------------------------
+
+Bug fixes/minor improvements:
+
+- Plug a memory leak in MPI_Mem_free().  Thanks to Philip Blakely for reporting.
+
 2.1.2 -- September, 2017
 ------------------------
 
diff --git a/opal/mca/mpool/base/mpool_base_alloc.c b/opal/mca/mpool/base/mpool_base_alloc.c
index 605ffbdf280..b34e438c1b6 100644
--- a/opal/mca/mpool/base/mpool_base_alloc.c
+++ b/opal/mca/mpool/base/mpool_base_alloc.c
@@ -14,6 +14,8 @@
  * Copyright (c) 2010      IBM Corporation.  All rights reserved.
  * Copyright (c) 2015      Los Alamos National Security, LLC.  All rights
  *                         reserved.
+ * Copyright (c) 2017      Research Organization for Information Science
+ *                         and Technology (RIST). All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -97,6 +99,7 @@ void *mca_mpool_base_alloc(size_t size, opal_info_t *info, const char *hints)
         mca_mpool_base_tree_item_put (mpool_tree_item);
     } else {
         mpool_tree_item->mpool = mpool;
+        mpool_tree_item->key = mem;
         mca_mpool_base_tree_insert (mpool_tree_item);
     }