bpo-39259: smtp.SMTP/SMTP_SSL now reject timeout = 0 (GH-17958)
diff --git a/Doc/library/smtplib.rst b/Doc/library/smtplib.rst
index 6176c35..f6ac123 100644
--- a/Doc/library/smtplib.rst
+++ b/Doc/library/smtplib.rst
@@ -70,6 +70,9 @@
.. versionadded:: 3.5
The SMTPUTF8 extension (:rfc:`6531`) is now supported.
+ .. versionchanged:: 3.9
+ If the *timeout* parameter is set to be zero, it will raise a
+ :class:`ValueError` to prevent the creation of a non-blocking socket
.. class:: SMTP_SSL(host='', port=0, local_hostname=None, keyfile=None, \
certfile=None [, timeout], context=None, \
@@ -108,6 +111,9 @@
:func:`ssl.create_default_context` select the system's trusted CA
certificates for you.
+ .. versionchanged:: 3.9
+ If the *timeout* parameter is set to be zero, it will raise a
+ :class:`ValueError` to prevent the creation of a non-blocking socket
.. class:: LMTP(host='', port=LMTP_PORT, local_hostname=None, source_address=None)
diff --git a/Doc/whatsnew/3.9.rst b/Doc/whatsnew/3.9.rst
index 859bf44..00409af 100644
--- a/Doc/whatsnew/3.9.rst
+++ b/Doc/whatsnew/3.9.rst
@@ -259,6 +259,13 @@
import attempts.
(Contributed by Ngalim Siregar in :issue:`37444`.)
+smtplib
+-------
+
+:class:`~smtplib.SMTP` and :class:`~smtplib.SMTP_SSL` now raise a :class:`ValueError`
+if the given timeout for their constructor is zero to prevent the creation of
+a non-blocking socket. (Contributed by Dong-hee Na in :issue:`39259`.)
+
signal
------
diff --git a/Lib/smtplib.py b/Lib/smtplib.py
index 6513842e..4d5cdb5 100755
--- a/Lib/smtplib.py
+++ b/Lib/smtplib.py
@@ -303,6 +303,8 @@
def _get_socket(self, host, port, timeout):
# This makes it simpler for SMTP_SSL to use the SMTP connect code
# and just alter the socket connection bit.
+ if timeout is not None and not timeout:
+ raise ValueError('Non-blocking socket (timeout=0) is not supported')
if self.debuglevel > 0:
self._print_debug('connect: to', (host, port), self.source_address)
return socket.create_connection((host, port), timeout,
@@ -1030,13 +1032,12 @@
keyfile=keyfile)
self.context = context
SMTP.__init__(self, host, port, local_hostname, timeout,
- source_address)
+ source_address)
def _get_socket(self, host, port, timeout):
if self.debuglevel > 0:
self._print_debug('connect:', (host, port))
- new_socket = socket.create_connection((host, port), timeout,
- self.source_address)
+ new_socket = super()._get_socket(host, port, timeout)
new_socket = self.context.wrap_socket(new_socket,
server_hostname=self._host)
return new_socket
@@ -1065,15 +1066,15 @@
ehlo_msg = "lhlo"
def __init__(self, host='', port=LMTP_PORT, local_hostname=None,
- source_address=None):
+ source_address=None):
"""Initialize a new instance."""
- SMTP.__init__(self, host, port, local_hostname=local_hostname,
- source_address=source_address)
+ super().__init__(host, port, local_hostname=local_hostname,
+ source_address=source_address)
def connect(self, host='localhost', port=0, source_address=None):
"""Connect to the LMTP daemon, on either a Unix or a TCP socket."""
if host[0] != '/':
- return SMTP.connect(self, host, port, source_address=source_address)
+ return super().connect(host, port, source_address=source_address)
# Handle Unix-domain sockets.
try:
diff --git a/Lib/test/test_smtplib.py b/Lib/test/test_smtplib.py
index faf013a..cc5c4b1 100644
--- a/Lib/test/test_smtplib.py
+++ b/Lib/test/test_smtplib.py
@@ -122,6 +122,11 @@
self.assertIsNone(smtp.sock.gettimeout())
smtp.close()
+ def testTimeoutZero(self):
+ mock_socket.reply_with(b"220 Hola mundo")
+ with self.assertRaises(ValueError):
+ smtplib.SMTP(HOST, self.port, timeout=0)
+
def testTimeoutValue(self):
mock_socket.reply_with(b"220 Hola mundo")
smtp = smtplib.SMTP(HOST, self.port, timeout=30)
diff --git a/Misc/NEWS.d/next/Library/2020-01-12-16-34-28.bpo-39259.J_yBVq.rst b/Misc/NEWS.d/next/Library/2020-01-12-16-34-28.bpo-39259.J_yBVq.rst
new file mode 100644
index 0000000..6cc490e
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-01-12-16-34-28.bpo-39259.J_yBVq.rst
@@ -0,0 +1,3 @@
+:class:`~smtplib.SMTP` and :class:`~smtplib.SMTP_SSL` now raise a
+:class:`ValueError` if the given timeout for their constructor is zero to
+prevent the creation of a non-blocking socket. Patch by Dong-hee Na.