MDB_VL32 fix cursor_unref - ignore cursor with empty stack

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 19930fcfc76780ab63ea8269241ef265b03c1944..ae32c9896124c1315500c017cf6a8a645757b43a 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -1952,7 +1952,7 @@ static void
 mdb_cursor_unref(MDB_cursor *mc)
 {
        int i;
-       if (!mc->mc_pg[0] || IS_SUBP(mc->mc_pg[0]))
+       if (!mc->mc_snum || !mc->mc_pg[0] || IS_SUBP(mc->mc_pg[0]))
                return;
        for (i=0; i<mc->mc_snum; i++)
                mdb_page_unref(mc->mc_txn, mc->mc_pg[i]);