CID fixes for memkind info code

This PR fixes CID 1645329 (USE_AFTER_FREE).
Coverty complained that there are scenarios where the string used within the code could have been already freed (probably in some multi-threaded settings). This PR should hopefully fix this.

Signed-off-by: Edgar Gabriel <edgar.gabriel@amd.com>

Author: edgargabriel

ompi/info/info_memkind.c

@@ -544,8 +544,8 @@ const char *ompi_info_memkind_cb (opal_infosubscriber_t *obj, const char *key, c
 int ompi_info_memkind_copy_or_set (opal_infosubscriber_t *parent, opal_infosubscriber_t *child,
                                    opal_info_t *info, ompi_info_memkind_assert_type *type)
 {
-    opal_cstring_t *parent_val;
-    opal_cstring_t *assert_val;
+    opal_cstring_t *parent_val = NULL;
+    opal_cstring_t *assert_val = NULL;
     ompi_info_memkind_assert_type assert_type = OMPI_INFO_MEMKIND_ASSERT_UNDEFINED;
     char *final_str = NULL;
     int flag;
@@ -569,7 +569,6 @@ int ompi_info_memkind_copy_or_set (opal_infosubscriber_t *parent, opal_infosubsc
         if (ret) {
             final_str = (char*) assert_val->string;
         }
-        OBJ_RELEASE(assert_val);
 
         opal_infosubscribe_subscribe (child, "mpi_assert_memory_alloc_kinds", final_str,
                                       ompi_info_memkind_cb);
@@ -578,12 +577,18 @@ int ompi_info_memkind_copy_or_set (opal_infosubscriber_t *parent, opal_infosubsc
  exit:
     opal_infosubscribe_subscribe (child, "mpi_memory_alloc_kinds", final_str,
                                   ompi_info_memkind_cb);
-    OBJ_RELEASE(parent_val);
 
     if (ompi_info_memkind_check_no_accel_from_string(final_str)) {
         assert_type = OMPI_INFO_MEMKIND_ASSERT_NO_ACCEL;
     }
 
+    if (NULL != assert_val) {
+        OBJ_RELEASE(assert_val);
+    }
+    if (NULL != parent_val) {
+        OBJ_RELEASE(parent_val);
+    }
+
     *type = assert_type;
     return OMPI_SUCCESS;
 }