Issue #16230: Fix a crash in select.select() when one the lists changes size while iterated on.
Patch by Serhiy Storchaka.
diff --git a/Lib/test/test_select.py b/Lib/test/test_select.py
index fe92f45..4ddc217 100644
--- a/Lib/test/test_select.py
+++ b/Lib/test/test_select.py
@@ -49,6 +49,16 @@
self.fail('Unexpected return values from select():', rfd, wfd, xfd)
p.close()
+ # Issue 16230: Crash on select resized list
+ def test_select_mutated(self):
+ a = []
+ class F:
+ def fileno(self):
+ del a[-1]
+ return sys.__stdout__.fileno()
+ a[:] = [F()] * 10
+ self.assertEqual(select.select([], a, []), ([], a[:5], []))
+
def test_main():
support.run_unittest(SelectTestCase)
support.reap_children()
diff --git a/Misc/NEWS b/Misc/NEWS
index 7ece312..4708e3f 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -143,6 +143,9 @@
Library
-------
+- Issue #16230: Fix a crash in select.select() when one the lists changes
+ size while iterated on. Patch by Serhiy Storchaka.
+
- Issue #16228: Fix a crash in the json module where a list changes size
while it is being encoded. Patch by Serhiy Storchaka.
diff --git a/Modules/selectmodule.c b/Modules/selectmodule.c
index 98b3108..0736215 100644
--- a/Modules/selectmodule.c
+++ b/Modules/selectmodule.c
@@ -83,7 +83,7 @@
{
int max = -1;
int index = 0;
- Py_ssize_t i, len = -1;
+ Py_ssize_t i;
PyObject* fast_seq = NULL;
PyObject* o = NULL;
@@ -94,9 +94,7 @@
if (!fast_seq)
return -1;
- len = PySequence_Fast_GET_SIZE(fast_seq);
-
- for (i = 0; i < len; i++) {
+ for (i = 0; i < PySequence_Fast_GET_SIZE(fast_seq); i++) {
SOCKET v;
/* any intervening fileno() calls could decr this refcnt */