diff --git a/pg_store_plans.c b/pg_store_plans.c
index a8f01ca..f60b67b 100644
--- a/pg_store_plans.c
+++ b/pg_store_plans.c
@@ -1579,6 +1579,12 @@ pg_store_plans_internal(FunctionCallInfo fcinfo,
 			else
 				pstr = SHMEM_PLAN_PTR(entry);
 
+			if (pstr == NULL)
+			{
+				values[i++] = CStringGetTextDatum("<invalid plan>");
+				goto outofblock01;
+			}
+
 			switch (plan_format)
 			{
 				case PLAN_FORMAT_TEXT:
@@ -1612,10 +1618,13 @@ pg_store_plans_internal(FunctionCallInfo fcinfo,
 				pfree(mstr);
 
 			/* pstr is a pointer onto pbuffer */
+
 		}
 		else
 			values[i++] = CStringGetTextDatum("<insufficient privilege>");
 
+		outofblock01:
+
 		/* copy counters to a local variable to keep locking time short */
 		{
 			volatile pgspEntry *e = (volatile pgspEntry *) entry;