diff --git a/rocksdb/rocksdb.nim b/rocksdb/rocksdb.nim
index 510a414..a04afe3 100644
--- a/rocksdb/rocksdb.nim
+++ b/rocksdb/rocksdb.nim
@@ -90,10 +90,12 @@ proc listRocksDbCFs*(
   bailOnErrors(errors)
 
   var cfs: seq[string]
-  for n in 0 ..< lencf:
-    if cList[n].isNil:
-      return err("short reply")
-    cfs.add $cList[n]
+  if not cList.isNil:
+    for n in 0 ..< lencf:
+      if cList[n].isNil:
+        return err("short reply")
+      cfs.add $cList[n]
+    rocksdb_free(cList)
 
   ok cfs