From 84d552b4b54086236dda96340be3017857d497bd Mon Sep 17 00:00:00 2001 From: Ray Donnelly Date: Wed, 28 Jul 2021 20:58:05 +0100 Subject: [PATCH] bpo-40263: Fixes an off-by-one error in _winapi_WaitForMultipleObjects_impl (GH-19501) (cherry picked from commit 92b5dc780db968f6277f42cb06926dddb7475dc6) Co-authored-by: Ray Donnelly --- .../next/Windows/2020-04-13-15-20-28.bpo-40263.1KKEbu.rst | 3 +++ Modules/_winapi.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/Windows/2020-04-13-15-20-28.bpo-40263.1KKEbu.rst diff --git a/Misc/NEWS.d/next/Windows/2020-04-13-15-20-28.bpo-40263.1KKEbu.rst b/Misc/NEWS.d/next/Windows/2020-04-13-15-20-28.bpo-40263.1KKEbu.rst new file mode 100644 index 00000000000000..0c31606d4928c8 --- /dev/null +++ b/Misc/NEWS.d/next/Windows/2020-04-13-15-20-28.bpo-40263.1KKEbu.rst @@ -0,0 +1,3 @@ +This is a follow-on bug from https://bugs.python.org/issue26903. Once that +is applied we run into an off-by-one assertion problem. The assert was not +correct. diff --git a/Modules/_winapi.c b/Modules/_winapi.c index f341493503c925..bf2498a017aff7 100644 --- a/Modules/_winapi.c +++ b/Modules/_winapi.c @@ -1722,7 +1722,7 @@ _winapi_WaitForMultipleObjects_impl(PyObject *module, PyObject *handle_seq, nhandles = PySequence_Length(handle_seq); if (nhandles == -1) return NULL; - if (nhandles < 0 || nhandles >= MAXIMUM_WAIT_OBJECTS - 1) { + if (nhandles < 0 || nhandles > MAXIMUM_WAIT_OBJECTS - 1) { PyErr_Format(PyExc_ValueError, "need at most %zd handles, got a sequence of length %zd", MAXIMUM_WAIT_OBJECTS - 1, nhandles);