ITS#8321 mdb_put cursor needs tracking too

libraries/liblmdb/mdb.c

@@ -8779,7 +8779,7 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno
 					m3->mc_ki[k+1] = m3->mc_ki[k];
 					m3->mc_pg[k+1] = m3->mc_pg[k];
 				}
-				if (m3->mc_ki[0] > nkeys) {
+				if (m3->mc_ki[0] >= nkeys) {
 					m3->mc_ki[0] = 1;
 				} else {
 					m3->mc_ki[0] = 0;
@@ -8821,6 +8821,7 @@ mdb_put(MDB_txn *txn, MDB_dbi dbi,
 {
 	MDB_cursor mc;
 	MDB_xcursor mx;
+	int rc;
 
 	if (!key || !data || !TXN_DBI_EXIST(txn, dbi, DB_USRVALID))
 		return EINVAL;
@@ -8832,7 +8833,11 @@ mdb_put(MDB_txn *txn, MDB_dbi dbi,
 		return (txn->mt_flags & MDB_TXN_RDONLY) ? EACCES : MDB_BAD_TXN;
 
 	mdb_cursor_init(&mc, txn, dbi, &mx);
-	return mdb_cursor_put(&mc, key, data, flags);
+	mc.mc_next = txn->mt_cursors[dbi];
+	txn->mt_cursors[dbi] = &mc;
+	rc = mdb_cursor_put(&mc, key, data, flags);
+	txn->mt_cursors[dbi] = mc.mc_next;
+	return rc;
 }
 
 #ifndef MDB_WBUF