gh-134744: Fix fcntl error handling (#134748)

Fix also reference leak on buffer overflow.
This commit is contained in:
Victor Stinner 2025-05-27 15:09:46 +02:00 committed by GitHub
parent 176b059fa0
commit 9300a596d3
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GPG key ID: B5690EEEBB952194
3 changed files with 28 additions and 4 deletions

View file

@ -11,7 +11,7 @@ from test.support import (
cpython_only, get_pagesize, is_apple, requires_subprocess, verbose
)
from test.support.import_helper import import_module
from test.support.os_helper import TESTFN, unlink
from test.support.os_helper import TESTFN, unlink, make_bad_fd
# Skip test if no fcntl module.
@ -274,6 +274,17 @@ class TestFcntl(unittest.TestCase):
def test_fcntl_large_buffer(self):
self._check_fcntl_not_mutate_len(2024)
@unittest.skipUnless(hasattr(fcntl, 'F_DUPFD'), 'need fcntl.F_DUPFD')
def test_bad_fd(self):
# gh-134744: Test error handling
fd = make_bad_fd()
with self.assertRaises(OSError):
fcntl.fcntl(fd, fcntl.F_DUPFD, 0)
with self.assertRaises(OSError):
fcntl.fcntl(fd, fcntl.F_DUPFD, b'\0' * 10)
with self.assertRaises(OSError):
fcntl.fcntl(fd, fcntl.F_DUPFD, b'\0' * 2048)
if __name__ == '__main__':
unittest.main()

View file

@ -5,7 +5,7 @@ import sys
import threading
import unittest
from test import support
from test.support import threading_helper
from test.support import os_helper, threading_helper
from test.support.import_helper import import_module
fcntl = import_module('fcntl')
termios = import_module('termios')
@ -201,6 +201,17 @@ class IoctlTestsPty(unittest.TestCase):
new_winsz = struct.unpack("HHHH", result)
self.assertEqual(new_winsz[:2], (20, 40))
@unittest.skipUnless(hasattr(fcntl, 'FICLONE'), 'need fcntl.FICLONE')
def test_bad_fd(self):
# gh-134744: Test error handling
fd = os_helper.make_bad_fd()
with self.assertRaises(OSError):
fcntl.ioctl(fd, fcntl.FICLONE, fd)
with self.assertRaises(OSError):
fcntl.ioctl(fd, fcntl.FICLONE, b'\0' * 10)
with self.assertRaises(OSError):
fcntl.ioctl(fd, fcntl.FICLONE, b'\0' * 2048)
if __name__ == "__main__":
unittest.main()

View file

@ -128,7 +128,7 @@ fcntl_fcntl_impl(PyObject *module, int fd, int code, PyObject *arg)
Py_END_ALLOW_THREADS
} while (ret == -1 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
if (ret < 0) {
if (async_err) {
if (!async_err) {
PyErr_SetFromErrno(PyExc_OSError);
}
Py_DECREF(result);
@ -136,6 +136,7 @@ fcntl_fcntl_impl(PyObject *module, int fd, int code, PyObject *arg)
}
if (ptr[len] != '\0') {
PyErr_SetString(PyExc_SystemError, "buffer overflow");
Py_DECREF(result);
return NULL;
}
return result;
@ -310,7 +311,7 @@ fcntl_ioctl_impl(PyObject *module, int fd, unsigned long code, PyObject *arg,
Py_END_ALLOW_THREADS
} while (ret == -1 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
if (ret < 0) {
if (async_err) {
if (!async_err) {
PyErr_SetFromErrno(PyExc_OSError);
}
Py_DECREF(result);
@ -318,6 +319,7 @@ fcntl_ioctl_impl(PyObject *module, int fd, unsigned long code, PyObject *arg,
}
if (ptr[len] != '\0') {
PyErr_SetString(PyExc_SystemError, "buffer overflow");
Py_DECREF(result);
return NULL;
}
return result;