bpo-30065: Fixed arguments validation in _posixsubprocess.fork_exec(). (#1110)
diff --git a/Lib/multiprocessing/util.py b/Lib/multiprocessing/util.py
index 1a2c0db..0ce274c 100644
--- a/Lib/multiprocessing/util.py
+++ b/Lib/multiprocessing/util.py
@@ -386,7 +386,7 @@
def spawnv_passfds(path, args, passfds):
import _posixsubprocess
- passfds = sorted(passfds)
+ passfds = tuple(sorted(map(int, passfds)))
errpipe_read, errpipe_write = os.pipe()
try:
return _posixsubprocess.fork_exec(
diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 76c340c..551aad3 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -1252,7 +1252,8 @@
fds_to_keep.add(errpipe_write)
self.pid = _posixsubprocess.fork_exec(
args, executable_list,
- close_fds, sorted(fds_to_keep), cwd, env_list,
+ close_fds, tuple(sorted(map(int, fds_to_keep))),
+ cwd, env_list,
p2cread, p2cwrite, c2pread, c2pwrite,
errread, errwrite,
errpipe_read, errpipe_write,
diff --git a/Lib/test/test_capi.py b/Lib/test/test_capi.py
index 6e14248..a95e4c5 100644
--- a/Lib/test/test_capi.py
+++ b/Lib/test/test_capi.py
@@ -98,7 +98,7 @@
def __len__(self):
return 1
self.assertRaises(TypeError, _posixsubprocess.fork_exec,
- 1,Z(),3,[1, 2],5,6,7,8,9,10,11,12,13,14,15,16,17)
+ 1,Z(),3,(1, 2),5,6,7,8,9,10,11,12,13,14,15,16,17)
# Issue #15736: overflow in _PySequence_BytesToCharpArray()
class Z(object):
def __len__(self):
@@ -106,7 +106,7 @@
def __getitem__(self, i):
return b'x'
self.assertRaises(MemoryError, _posixsubprocess.fork_exec,
- 1,Z(),3,[1, 2],5,6,7,8,9,10,11,12,13,14,15,16,17)
+ 1,Z(),3,(1, 2),5,6,7,8,9,10,11,12,13,14,15,16,17)
@unittest.skipUnless(_posixsubprocess, '_posixsubprocess required for this test.')
def test_subprocess_fork_exec(self):
@@ -116,7 +116,7 @@
# Issue #15738: crash in subprocess_fork_exec()
self.assertRaises(TypeError, _posixsubprocess.fork_exec,
- Z(),[b'1'],3,[1, 2],5,6,7,8,9,10,11,12,13,14,15,16,17)
+ Z(),[b'1'],3,(1, 2),5,6,7,8,9,10,11,12,13,14,15,16,17)
@unittest.skipIf(MISSING_C_DOCSTRINGS,
"Signature information for builtins requires docstrings")
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
index 8511207..f01bd1a 100644
--- a/Lib/test/test_subprocess.py
+++ b/Lib/test/test_subprocess.py
@@ -2418,7 +2418,7 @@
with self.assertRaises(TypeError):
_posixsubprocess.fork_exec(
args, exe_list,
- True, [], cwd, env_list,
+ True, (), cwd, env_list,
-1, -1, -1, -1,
1, 2, 3, 4,
True, True, func)
@@ -2430,6 +2430,16 @@
def test_fork_exec_sorted_fd_sanity_check(self):
# Issue #23564: sanity check the fork_exec() fds_to_keep sanity check.
import _posixsubprocess
+ class BadInt:
+ first = True
+ def __init__(self, value):
+ self.value = value
+ def __int__(self):
+ if self.first:
+ self.first = False
+ return self.value
+ raise ValueError
+
gc_enabled = gc.isenabled()
try:
gc.enable()
@@ -2440,6 +2450,7 @@
(18, 23, 42, 2**63), # Out of range.
(5, 4), # Not sorted.
(6, 7, 7, 8), # Duplicate.
+ (BadInt(1), BadInt(2)),
):
with self.assertRaises(
ValueError,
diff --git a/Modules/_posixsubprocess.c b/Modules/_posixsubprocess.c
index 5007a39..d1434d5 100644
--- a/Modules/_posixsubprocess.c
+++ b/Modules/_posixsubprocess.c
@@ -111,13 +111,17 @@
static int
_sanity_check_python_fd_sequence(PyObject *fd_sequence)
{
- Py_ssize_t seq_idx, seq_len = PySequence_Length(fd_sequence);
+ Py_ssize_t seq_idx;
long prev_fd = -1;
- for (seq_idx = 0; seq_idx < seq_len; ++seq_idx) {
- PyObject* py_fd = PySequence_Fast_GET_ITEM(fd_sequence, seq_idx);
- long iter_fd = PyLong_AsLong(py_fd);
+ for (seq_idx = 0; seq_idx < PyTuple_GET_SIZE(fd_sequence); ++seq_idx) {
+ PyObject* py_fd = PyTuple_GET_ITEM(fd_sequence, seq_idx);
+ long iter_fd;
+ if (!PyLong_Check(py_fd)) {
+ return 1;
+ }
+ iter_fd = PyLong_AsLong(py_fd);
if (iter_fd < 0 || iter_fd <= prev_fd || iter_fd > INT_MAX) {
- /* Negative, overflow, not a Long, unsorted, too big for a fd. */
+ /* Negative, overflow, unsorted, too big for a fd. */
return 1;
}
prev_fd = iter_fd;
@@ -132,13 +136,12 @@
{
/* Binary search. */
Py_ssize_t search_min = 0;
- Py_ssize_t search_max = PySequence_Length(fd_sequence) - 1;
+ Py_ssize_t search_max = PyTuple_GET_SIZE(fd_sequence) - 1;
if (search_max < 0)
return 0;
do {
long middle = (search_min + search_max) / 2;
- long middle_fd = PyLong_AsLong(
- PySequence_Fast_GET_ITEM(fd_sequence, middle));
+ long middle_fd = PyLong_AsLong(PyTuple_GET_ITEM(fd_sequence, middle));
if (fd == middle_fd)
return 1;
if (fd > middle_fd)
@@ -154,9 +157,9 @@
{
Py_ssize_t i, len;
- len = PySequence_Length(py_fds_to_keep);
+ len = PyTuple_GET_SIZE(py_fds_to_keep);
for (i = 0; i < len; ++i) {
- PyObject* fdobj = PySequence_Fast_GET_ITEM(py_fds_to_keep, i);
+ PyObject* fdobj = PyTuple_GET_ITEM(py_fds_to_keep, i);
long fd = PyLong_AsLong(fdobj);
assert(!PyErr_Occurred());
assert(0 <= fd && fd <= INT_MAX);
@@ -213,14 +216,13 @@
_close_fds_by_brute_force(long start_fd, PyObject *py_fds_to_keep)
{
long end_fd = safe_get_max_fd();
- Py_ssize_t num_fds_to_keep = PySequence_Length(py_fds_to_keep);
+ Py_ssize_t num_fds_to_keep = PyTuple_GET_SIZE(py_fds_to_keep);
Py_ssize_t keep_seq_idx;
int fd_num;
/* As py_fds_to_keep is sorted we can loop through the list closing
* fds inbetween any in the keep list falling within our range. */
for (keep_seq_idx = 0; keep_seq_idx < num_fds_to_keep; ++keep_seq_idx) {
- PyObject* py_keep_fd = PySequence_Fast_GET_ITEM(py_fds_to_keep,
- keep_seq_idx);
+ PyObject* py_keep_fd = PyTuple_GET_ITEM(py_fds_to_keep, keep_seq_idx);
int keep_fd = PyLong_AsLong(py_keep_fd);
if (keep_fd < start_fd)
continue;
@@ -306,7 +308,7 @@
/* Close all open file descriptors from start_fd and higher.
- * Do not close any in the sorted py_fds_to_keep list.
+ * Do not close any in the sorted py_fds_to_keep tuple.
*
* This function violates the strict use of async signal safe functions. :(
* It calls opendir(), readdir() and closedir(). Of these, the one most
@@ -562,8 +564,9 @@
#endif
if (!PyArg_ParseTuple(
- args, "OOpOOOiiiiiiiiiiO:fork_exec",
- &process_args, &executable_list, &close_fds, &py_fds_to_keep,
+ args, "OOpO!OOiiiiiiiiiiO:fork_exec",
+ &process_args, &executable_list,
+ &close_fds, &PyTuple_Type, &py_fds_to_keep,
&cwd_obj, &env_list,
&p2cread, &p2cwrite, &c2pread, &c2pwrite,
&errread, &errwrite, &errpipe_read, &errpipe_write,
@@ -574,10 +577,6 @@
PyErr_SetString(PyExc_ValueError, "errpipe_write must be >= 3");
return NULL;
}
- if (PySequence_Length(py_fds_to_keep) < 0) {
- PyErr_SetString(PyExc_ValueError, "cannot get length of fds_to_keep");
- return NULL;
- }
if (_sanity_check_python_fd_sequence(py_fds_to_keep)) {
PyErr_SetString(PyExc_ValueError, "bad value(s) in fds_to_keep");
return NULL;
@@ -631,6 +630,10 @@
goto cleanup;
for (arg_num = 0; arg_num < num_args; ++arg_num) {
PyObject *borrowed_arg, *converted_arg;
+ if (PySequence_Fast_GET_SIZE(fast_args) != num_args) {
+ PyErr_SetString(PyExc_RuntimeError, "args changed during iteration");
+ goto cleanup;
+ }
borrowed_arg = PySequence_Fast_GET_ITEM(fast_args, arg_num);
if (PyUnicode_FSConverter(borrowed_arg, &converted_arg) == 0)
goto cleanup;