extmod/modbtree: do CHECK_ERROR after __bt_seq()

Krzysztof Blazewicz · pfalcon · commit 5a5449d4eb46 · 2016-08-24T01:31:16.000+03:00
In `btree_seq()`, when `__bt_seq()` gets called with invalid
`flags` argument it will return `RET_ERROR` and it won't
initialize `val`. If field `data` of uninitialized `val`
is passed to `mp_obj_new_bytes()` it causes a segfault.
diff --git a/extmod/modbtree.c b/extmod/modbtree.c
@@ -133,6 +133,7 @@ STATIC mp_obj_t btree_seq(size_t n_args, const mp_obj_t *args) {
     }
 
     int res = __bt_seq(self->db, &key, &val, flags);
+    CHECK_ERROR(res);
     if (res == RET_SPECIAL) {
         return mp_const_none;
     }

Original file line number	Diff line number	Diff line change
`@@ -133,6 +133,7 @@ STATIC mp_obj_t btree_seq(size_t n_args, const mp_obj_t *args) {`
`133`	`133`	`}`
`134`	`134`
`135`	`135`	`int res = __bt_seq(self->db, &key, &val, flags);`
	`136`	`+ CHECK_ERROR(res);`
`136`	`137`	`if (res == RET_SPECIAL) {`
`137`	`138`	`return mp_const_none;`
`138`	`139`	`}`