fstat may block for long time if the file descriptor is on a
non-responsive NFS server, hanging all threads. Most fstat() calls are
handled by _Py_fstat(), releasing the GIL internally, but but
_Py_fstat_noraise() does not release the GIL, and most calls release the
GIL explicitly around it.
This patch fixes last 2 calls to _Py_fstat_no_raise(), avoiding hangs
when calling:
- mmap.mmap()
- os.urandom()
- random.seed()
In some conditions the standard streams will be None or closed in the child process (for example if using "pythonw" instead of "python" on Windows). Avoid failing with a non-0 exit code in those conditions.
Report and initial patch by poxthegreat.
Fix a crash on fork when using a custom memory allocator (ex: using
PYTHONMALLOC env var).
_PyGILState_Reinit() and _PyInterpreterState_Enable() now use the
default RAW memory allocator to allocate a new interpreters mutex on
fork.
Like Python, IDLE optionally runs one startup file in the Shell window
before presenting the first interactive input prompt. For IDLE,
option -s runs a file named in environmental variable IDLESTARTUP or
PYTHONSTARTUP; -r file runs file. Python sets __file__ to the startup
file name before running the file and unsets it before the first
prompt. IDLE now does the same when run normally, without the -n
option.
* Prevent low-grade poplib REDOS (CVE-2018-1060)
The regex to test a mail server's timestamp is susceptible to
catastrophic backtracking on long evil responses from the server.
Happily, the maximum length of malicious inputs is 2K thanks
to a limit introduced in the fix for CVE-2013-1752.
A 2KB evil response from the mail server would result in small slowdowns
(milliseconds vs. microseconds) accumulated over many apop calls.
This is a potential DOS vector via accumulated slowdowns.
Replace it with a similar non-vulnerable regex.
The new regex is RFC compliant.
The old regex was non-compliant in edge cases.
* Prevent difflib REDOS (CVE-2018-1061)
The default regex for IS_LINE_JUNK is susceptible to
catastrophic backtracking.
This is a potential DOS vector.
Replace it with an equivalent non-vulnerable regex.
Also introduce unit and REDOS tests for difflib.
Co-authored-by: Tim Peters <tim.peters@gmail.com>
Co-authored-by: Christian Heimes <christian@python.org>
OpenSSL 1.1 has introduced a new API to set the minimum and maximum
supported protocol version. The API is easier to use than the old
OP_NO_TLS1 option flags, too.
Since OpenSSL has no call to set minimum version to highest supported,
the implementation emulate maximum_version = MINIMUM_SUPPORTED and
minimum_version = MAXIMUM_SUPPORTED by figuring out the minumum and
maximum supported version at compile time.
Signed-off-by: Christian Heimes <christian@python.org>
Direct instantiation of SSLSocket and SSLObject objects is now prohibited.
The constructors were never documented, tested, or designed as public
constructors. The SSLSocket constructor had limitations. For example it was
not possible to enabled hostname verification except was
ssl_version=PROTOCOL_TLS_CLIENT with cert_reqs=CERT_REQUIRED.
SSLContext.wrap_socket() and SSLContext.wrap_bio are the recommended API
to construct SSLSocket and SSLObject instances. ssl.wrap_socket() is
also deprecated.
The only test case for direct instantiation was added a couple of days
ago for IDNA testing.
Signed-off-by: Christian Heimes <christian@python.org>
The ssl module function ssl.wrap_socket() has been de-emphasized
and deprecated in favor of the more secure and efficient
SSLContext.wrap_socket() method.
Signed-off-by: Christian Heimes <christian@python.org>
* bpo-32947: OpenSSL 1.1.1-pre1 / TLS 1.3 fixes
Misc fixes and workarounds for compatibility with OpenSSL 1.1.1-pre1 and
TLS 1.3 support. With OpenSSL 1.1.1, Python negotiates TLS 1.3 by
default. Some test cases only apply to TLS 1.2. Other tests currently
fail because the threaded or async test servers stop after failure.
I'm going to address these issues when OpenSSL 1.1.1 reaches beta.
OpenSSL 1.1.1 has added a new option OP_ENABLE_MIDDLEBOX_COMPAT for TLS
1.3. The feature is enabled by default for maximum compatibility with
broken middle boxes. Users should be able to disable the hack and CPython's test suite needs
it to verify default options.
Signed-off-by: Christian Heimes <christian@python.org>
When comprehensions switched to using a nested scope, the old
code for generating a temporary name to hold the accumulation
target became redundant, but was never actually removed.
Patch by Nitish Chandra.
unsafe_hash=False is now the default. It is the same behavior as the old hash=None parameter. unsafe_hash=True will try to add __hash__. If it already exists, TypeError is raised.
The ctypes module used to depend on indirect linking for dlopen. The shared
extension is now explicitly linked against libdl on platforms with dl.
Signed-off-by: Christian Heimes <christian@python.org>
The ssl module now detects missing NPN support in LibreSSL.
Co-Authored-By: Bernard Spil <brnrd@FreeBSD.org>
Signed-off-by: Christian Heimes <christian@python.org>
* The SSLSocket is no longer implemented on top of SSLObject to
avoid an extra level of indirection.
* Owner and session are now handled in the internal constructor.
* _ssl._SSLSocket now uses the same method names as SSLSocket and
SSLObject.
* Channel binding type check is now handled in C code. Channel binding
is always available.
The patch also changes the signature of SSLObject.__init__(). In my
opinion it's fine. A SSLObject is not a user-constructable object.
SSLContext.wrap_bio() is the only valid factory.
ssl.match_hostname() has been simplified and no longer depends on re and
ipaddress module for wildcard and IP addresses. Error reporting for invalid
wildcards has been improved.
Signed-off-by: Christian Heimes <christian@python.org>
Previously, the ssl module stored international domain names (IDNs)
as U-labels. This is problematic for a number of reasons -- for
example, it made it impossible for users to use a different version
of IDNA than the one built into Python.
After this change, we always convert to A-labels as soon as possible,
and use them for all internal processing. In particular, server_hostname
attribute is now an A-label, and on the server side there's a new
sni_callback that receives the SNI servername as an A-label rather than
a U-label.
Make test.support.temp_cwd() fork-safe. The context manager test.support.temp_cwd() no longer removes the temporary directory when executing in a process other than the parent it entered from.
If a forked child exits the context manager it won't do the cleanup.
dump is similar to print but less flexible. lastopenbracketpos is now always initialized in _study2, as was stmt_bracketing, so the class settings are not needed. get_last_open_bracket_pos is never called.
os.dup2() tests for dup3() system call availability at runtime,
but doesn't remember the result across calls, repeating
the test on each call with inheritable=False.
Since the caller of os.dup2() is expected to hold the GIL,
fix this by making the variable holding the test result static.
GUI test test_file_buttons() only looks at initial ascii-only lines,
but failed on systems where open() defaults to 'ascii' because
readline() internally reads and decodes far enough ahead to encounter
a non-ascii character in CREDITS.txt.
fnmatch.translate() no longer produces patterns which contain set
operations.
Sets starting with '[' or containing '--', '&&', '~~' or '||' will
be interpreted differently in regular expressions in future versions.
Currently they emit warnings. fnmatch.translate() now avoids producing
patterns containing such sets by accident.
Fix a rare but potential pre-exec child process deadlock in subprocess on POSIX systems when marking file descriptors inheritable on exec in the child process. This bug appears to have been introduced in 3.4 with the inheritable file descriptors support.
This also changes Python/fileutils.c `set_inheritable` to use the "slow" two `fcntl` syscall path instead of the "fast" single `ioctl` syscall path when asked to be async signal safe (by way of being asked not to raise exceptions). `ioctl` is not a POSIX async-signal-safe approved function.
ref: http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html
When `__getattr__` is implemented, attribute lookup will always fall back to that,
even if the initial failure comes from `__getattribute__` or a descriptor's `__get__`
method (including property methods).
Modify RE examples in documentation to use raw strings to prevent DeprecationWarning.
Add text to REGEX HOWTO to highlight the deprecation. Approved by Serhiy Storchaka.
In the tutorial about the Generator expression, there is an example with
a dict comprehension and not with a generator expression, just removed
the code.
This issue covers various changes for the macOS installers provided via python.org for 3.7.0.
- Provide a provisional new installer variant for macOS 10.9 and later systems with 64-bit (x86_64) architecture only. Apple has made it known that future versions of macOS will only fully support 64-bit executables and some other third-party software suppliers have chosen 10.9 as their oldest supported system.
- Support **Tcl/Tk 8.6** with the 10.9 installer variant.
- Upgrade **OpenSSL** to 1.1.0g and **SQLite** to 3.22.0.
- The compiler name used for the interpreter build and for modules built with **Distutils / pip** is now _gcc_ rather than _gcc-4.2_. And extension module builds will no longer try to force use of an old SDK if present.
No longer add /Library/Python/3.x/site-packages, the Apple-supplied
system Python site-packages directory, to sys.path for macOS framework
builds in case Apple ships a version of Python 3. A similar change
was made earlier to Python 2.7 where it was found that the coupling
between the system Python and a user-installed framework Python often
caused confusion or pip install failures.
This allows the compression level to be specified when writing zipfiles
(for the entire file *and* overridden on a per-file basis).
Contributed by Bo Bayles
Do not allow receiving a SIGINT to cause the subprocess module to trigger an
immediate SIGKILL of the child process. SIGINT is normally sent to all child
processes by the OS at the same time already as was the established normal
behavior in 2.7 and 3.2. This behavior change was introduced during the fix to https://bugs.python.org/issue12494 and is generally surprising to command line
tool users who expect other tools launched in child processes to get their own
SIGINT and do their own cleanup.
In Python 3.3-3.6 subprocess.call and subprocess.run would immediately
SIGKILL the child process upon receiving a SIGINT (which raises a
KeyboardInterrupt). We now give the child a small amount of time to
exit gracefully before resorting to a SIGKILL.
This is also the case for subprocess.Popen.__exit__ which would
previously block indefinitely waiting for the child to die. This was
hidden from many users by virtue of subprocess.call and subprocess.run
sending the signal immediately.
Behavior change: subprocess.Popen.__exit__ will not block indefinitely
when the exiting exception is a KeyboardInterrupt. This is done for
user friendliness as people expect their ^C to actually happen. This
could cause occasional orphaned Popen objects when not using `call` or
`run` with a child process that hasn't exited.
Refactoring involved: The Popen.wait method deals with the
KeyboardInterrupt second chance, existing platform specific internals
have been renamed to _wait().
Also fixes comment typos.
Fix socket(fileno=fd) by auto-detecting the socket's family, type,
and proto from the file descriptor. The auto-detection can be overruled
by passing in family, type, and proto explicitly.
Without the fix, all socket except for TCP/IP over IPv4 are basically broken:
>>> s = socket.create_connection(('www.python.org', 443))
>>> s
<socket.socket fd=3, family=AddressFamily.AF_INET6, type=SocketKind.SOCK_STREAM, proto=6, laddr=('2003:58:bc4a:3b00:56ee:75ff:fe47:ca7b', 59730, 0, 0), raddr=('2a04:4e42:1b::223', 443, 0, 0)>
>>> socket.socket(fileno=s.fileno())
<socket.socket fd=3, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('2003:58:bc4a:3b00::%2550471192', 59730, 0, 2550471192), raddr=('2a04:4e42:1b:0:700c:e70b:ff7f:0%2550471192', 443, 0, 2550471192)>
Signed-off-by: Christian Heimes <christian@python.org>
The commit removes one unnecessary "if" clause in genobject.c. That "if" clause was masking un-awaited coroutines warnings just to make writing unittests more convenient.
Add test cases for IDNA 2003 and 2008 host names. IDNA 2003
internationalized host names are working since bpo-31399 has landed. IDNA
2008 deviations are still broken and will be fixed in another patch.
Signed-off-by: Christian Heimes <christian@python.org>
Until now Python used a hard coded white list of default TLS cipher
suites. The old approach has multiple downsides. OpenSSL's default
selection was completely overruled. Python did neither benefit from new
cipher suites (ChaCha20, TLS 1.3 suites) nor blacklisted cipher suites.
For example we used to re-enable 3DES.
Python now defaults to OpenSSL DEFAULT cipher suite selection and black
lists all unwanted ciphers. Downstream vendors can override the default
cipher list with --with-ssl-default-suites.
Signed-off-by: Christian Heimes <christian@python.org>
Better account for single-line compound statements and
semi-colon separated statements when suggesting
Py3 replacements for Py2 print statements.
Initial patch by Nitish Chandra.
Class authors no longer need to specify repr=False if they want to provide a custom __repr__ for dataclasses. The same thing applies for the other dunder methods that the dataclass decorator adds. If dataclass finds that a dunder methods is defined in the class, it will not overwrite it.
bpo-31399: Let OpenSSL verify hostname and IP
The ssl module now uses OpenSSL's X509_VERIFY_PARAM_set1_host() and
X509_VERIFY_PARAM_set1_ip() API to verify hostname and IP addresses.
* Remove match_hostname calls
* Check for libssl with set1_host, libssl must provide X509_VERIFY_PARAM_set1_host()
* Add documentation for OpenSSL 1.0.2 requirement
* Don't support OpenSSL special mode with a leading dot, e.g. ".example.org" matches "www.example.org". It's not standard conform.
* Add hostname_checks_common_name
Signed-off-by: Christian Heimes <christian@python.org>
The hmac module now has hmac.digest(), which provides an optimized HMAC
digest for short messages. hmac.digest() is up to three times faster
than hmac.HMAC().digest().
Signed-off-by: Christian Heimes <christian@python.org>
dictview_repr(): Use a Py_ReprEnter() / Py_ReprLeave() pair to check
for recursion, and produce "..." if so.
test_recursive_repr(): Check for the string rather than a
RecursionError. (Test cannot be any tighter as contents are
implementation-dependent.)
test_deeply_nested_repr(): Add new test, replacing the original
test_recursive_repr(). It checks that a RecursionError is raised in
the case of a non-recursive but deeply nested structure. (Very
similar to what test_repr_deep() in test/test_dict.py does for a
normal dict.)
OrderedDictTests: Add new test case, to test behavior on OrderedDict
instances containing their own values() or items().
* bpo-32662: Implement Server.start_serving() and Server.serve_forever()
New methods:
* Server.start_serving(),
* Server.serve_forever(), and
* Server.is_serving().
Add 'start_serving' keyword parameter to loop.create_server() and
loop.create_unix_server().
Nir Soffer
Antoine Pitrou
Serhiy Storchaka
Emanuele Gaifas
Xiang Zhang
Andrew Svetlov
Alexey Izbyshev
INADA Naoki
Yury Selivanov
Victor Stinner
Steve Dower
Terry Jan Reedy
Cheryl Sabella
Jamie Davis
Jon Wayne Parrott
Ned Deily
Christian Heimes
Eric V. Smith
Joffrey F
Tobotimus
Nitish Chandra
Sergey Fedoseev
animalize
Anselm Kruis
Eddie Elizondo
Paul Price
Zackery Spytz
chason
Éric Araujo
Ivan Levkivskyi
Kyle Altendorf
Bar Harel
Oren Milman
Segev Finer
Коренберг Марк
SSE4
Raymond Hettinger
sblondon
Alan D Moore
Mario Corchero
Barry Warsaw
Stéphane Wirtel
Bernhard M. Wiedemann
John Jolly
Anders Lorentsen
Bo Bayles
Benjamin Peterson
Gregory P. Smith
Eric Snow
Mark Shannon
Pablo Galindo
jayyyin
embg
larryhastings
jcea
Nick Coghlan
Mads Jensen
bennorth
mwidjaja
José Melero Fernández
Ilya Kulakov