From 54dac6c0f4fa24d03025c45899ee7c5f2a4c367e Mon Sep 17 00:00:00 2001 From: "Miss Islington (bot)" <31488909+miss-islington@users.noreply.github.com> Date: Tue, 3 Sep 2019 13:13:41 -0700 Subject: [PATCH] bpo-38020: Fixes crash in os.readlink() on Windows (GH-15663) (cherry picked from commit 993ac92418839427d4068d6ae8e618b06b5d9294) Co-authored-by: Steve Dower --- .../next/Windows/2019-09-03-11-47-37.bpo-38020.xFZ2j0.rst | 2 ++ Modules/posixmodule.c | 4 ++-- 2 files changed, 4 insertions(+), 2 deletions(-) create mode 100644 Misc/NEWS.d/next/Windows/2019-09-03-11-47-37.bpo-38020.xFZ2j0.rst diff --git a/Misc/NEWS.d/next/Windows/2019-09-03-11-47-37.bpo-38020.xFZ2j0.rst b/Misc/NEWS.d/next/Windows/2019-09-03-11-47-37.bpo-38020.xFZ2j0.rst new file mode 100644 index 0000000000..e6ddaba2f6 --- /dev/null +++ b/Misc/NEWS.d/next/Windows/2019-09-03-11-47-37.bpo-38020.xFZ2j0.rst @@ -0,0 +1,2 @@ +Fixes potential crash when calling :func:`os.readlink` (or indirectly +through :func:`~os.path.realpath`) on a file that is not a supported link. diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c index c178facc4b..b9e8c0d94c 100644 --- a/Modules/posixmodule.c +++ b/Modules/posixmodule.c @@ -7821,7 +7821,7 @@ os_readlink_impl(PyObject *module, path_t *path, int dir_fd) HANDLE reparse_point_handle; char target_buffer[_Py_MAXIMUM_REPARSE_DATA_BUFFER_SIZE]; _Py_REPARSE_DATA_BUFFER *rdb = (_Py_REPARSE_DATA_BUFFER *)target_buffer; - PyObject *result; + PyObject *result = NULL; /* First get a handle to the reparse point */ Py_BEGIN_ALLOW_THREADS @@ -7875,7 +7875,7 @@ os_readlink_impl(PyObject *module, path_t *path, int dir_fd) name[1] = L'\\'; } result = PyUnicode_FromWideChar(name, nameLen); - if (path->narrow) { + if (result && path->narrow) { Py_SETREF(result, PyUnicode_EncodeFSDefault(result)); } } -- 2.50.0