Fix small query-lifespan memory leak in bulk updates.

When there is an identifiable REPLICA IDENTITY index on the target table,
heap_update leaks the id_attrs bitmapset.  That's not many bytes, but it
adds up over enough rows, since the code typically runs in a query-lifespan
context.  Bug introduced in commit e55704d8b, which did a rather poor job
of cloning the existing use-pattern for RelationGetIndexAttrBitmap().

Per bug #14293 from Zhou Digoal.  Back-patch to 9.4 where the bug was
introduced.

Report: <20160824114320.15676.45171@wrigleys.postgresql.org>

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index c63dfa0bafc606ea3dc1ee9c7427d92c28ed09d4..6a27ef4140091b0c53d3a68f9d947824b2ffe8c2 100644 (file)
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -3802,6 +3802,7 @@ l2:
            ReleaseBuffer(vmbuffer);
        bms_free(hot_attrs);
        bms_free(key_attrs);
+       bms_free(id_attrs);
        return result;
    }
 
@@ -4268,6 +4269,7 @@ l2:
 
    bms_free(hot_attrs);
    bms_free(key_attrs);
+   bms_free(id_attrs);
 
    return HeapTupleMayBeUpdated;
 }