Make sure mdb_open actually got a sub-db record

diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index dd60fb1af06a25b81f0fd68f3e4edb7267327558..c09f479308c04ef6cea6d388493ff3df73328b43 100644 (file)
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -5642,7 +5642,8 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
 {
        MDB_val key, data;
        MDB_dbi i;
-       int rc, dbflag = 0;
+       MDB_cursor mc;
+       int rc, dbflag, exact;
        size_t len;
 
        if (txn->mt_dbxs[FREE_DBI].md_cmp == NULL) {
@@ -5676,20 +5677,25 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
                return ENFILE;
 
        /* Find the DB info */
+       dbflag = 0;
+       exact = 0;
        key.mv_size = len;
        key.mv_data = (void *)name;
-       rc = mdb_get(txn, MAIN_DBI, &key, &data);
-
-       /* Create if requested */
-       if (rc == MDB_NOTFOUND && (flags & MDB_CREATE)) {
-               MDB_cursor mc;
+       mdb_cursor_init(&mc, txn, MAIN_DBI, NULL);
+       rc = mdb_cursor_set(&mc, &key, &data, MDB_SET, &exact);
+       if (rc == MDB_SUCCESS) {
+               /* make sure this is actually a DB */
+               MDB_node *node = NODEPTR(mc.mc_pg[mc.mc_top], mc.mc_ki[mc.mc_top]);
+               if (!(node->mn_flags & F_SUBDATA))
+                       return EINVAL;
+       } else if (rc == MDB_NOTFOUND && (flags & MDB_CREATE)) {
+               /* Create if requested */
                MDB_db dummy;
                data.mv_size = sizeof(MDB_db);
                data.mv_data = &dummy;
                memset(&dummy, 0, sizeof(dummy));
                dummy.md_root = P_INVALID;
                dummy.md_flags = flags & 0xffff;
-               mdb_cursor_init(&mc, txn, MAIN_DBI, NULL);
                rc = mdb_cursor_put(&mc, &key, &data, F_SUBDATA);
                dbflag = DB_DIRTY;
        }