If waitpid() is called elsewhere, waitpid() call fails with
ChildProcessError: use return code 255 in this case, and log a
warning. It ensure that the pidfd file descriptor is closed if this
error occurs.
Break cycle generated when saving an exception in socket.py, codeop.py and dyld.py as they keep alive not only the exception but user objects through the ``__traceback__`` attribute.
https://bugs.python.org/issue36820
Automerge-Triggered-By: @pablogsal
parse_message_id() was improperly using a token defined inside an exception
handler, which was raising `UnboundLocalError` on parsing an invalid value.
https://bugs.python.org/issue38698
Since c64a1a61e6 two assertions were indented and thus ignored when running test_hmac.
This PR fixes it. As the change is quite trivial I didn't add a NEWS entry.
https://bugs.python.org/issue38270
Make ssl tests less strict and also accept TLSv3 as the default maximum
version. This change unbreaks test_min_max_version on Fedora 32.
https://bugs.python.org/issue38815
* bpo-20928: bring elementtree's XInclude support en-par with the implementation in lxml by adding support for recursive includes and a base-URL.
* bpo-20928: Support xincluding the same file multiple times, just not recursively.
* bpo-20928: Add 'max_depth' parameter to xinclude that limits the maximum recursion depth to 6 by default.
* Add news entry for updated ElementInclude support
Add ast.unparse() as a function in the ast module that can be used to unparse an
ast.AST object and produce a string with code that would produce an equivalent ast.AST
object when parsed.
Extra newlines are removed at the end of non-shell files. If the file only has newlines after stripping other trailing whitespace, all are removed, as is done by patchcheck.py.
The previous code was raising a `KeyError` for both the Python and C implementation.
This was caused by the specified index of an invalid input which did not exist
in the memo structure, where the pickle stores what objects it has seen.
The malformed input would have caused either a `BINGET` or `LONG_BINGET` load
from the memo, leading to a `KeyError` as the determined index was bogus.
https://bugs.python.org/issue38876https://bugs.python.org/issue38876
This patch enables downstream projects inspecting a TypedDict subclass at runtime to tell which keys are optional.
This is essential for generating test data with Hypothesis or validating inputs with typeguard or pydantic.
* fix HTTP Digest handling in request.py
There is a bug triggered when server replies to a request with `WWW-Authenticate: Digest` where `qop="auth,auth-int"` rather than mere `qop="auth"`. Having both `auth` and `auth-int` is legitimate according to the `qop-options` rule in §3.2.1 of [[https://www.ietf.org/rfc/rfc2617.txt|RFC 2617]]:
> qop-options = "qop" "=" <"> 1#qop-value <">
> qop-value = "auth" | "auth-int" | token
> **qop-options**: [...] If present, it is a quoted string **of one or more** tokens indicating the "quality of protection" values supported by the server. The value `"auth"` indicates authentication; the value `"auth-int"` indicates authentication with integrity protection
This is description confirmed by the definition of the [//n//]`#`[//m//]//rule// extended-BNF pattern defined in §2.1 of [[https://www.ietf.org/rfc/rfc2616.txt|RFC 2616]] as 'a comma-separated list of //rule// with at least //n// and at most //m// items'.
When this reply is parsed by `get_authorization`, request.py only tests for identity with `'auth'`, failing to recognize it as one of the supported modes the server announced, and claims that `"qop 'auth,auth-int' is not supported"`.
* 📜🤖 Added by blurb_it.
* bpo-38686 review fix: remember why.
* fix trailing space in Lib/urllib/request.py
Co-Authored-By: Brandt Bucher <brandtbucher@gmail.com>
The regex http.cookiejar.LOOSE_HTTP_DATE_RE was vulnerable to regular
expression denial of service (REDoS).
LOOSE_HTTP_DATE_RE.match is called when using http.cookiejar.CookieJar
to parse Set-Cookie headers returned by a server.
Processing a response from a malicious HTTP server can lead to extreme
CPU usage and execution will be blocked for a long time.
The regex contained multiple overlapping \s* capture groups.
Ignoring the ?-optional capture groups the regex could be simplified to
\d+-\w+-\d+(\s*\s*\s*)$
Therefore, a long sequence of spaces can trigger bad performance.
Matching a malicious string such as
LOOSE_HTTP_DATE_RE.match("1-c-1" + (" " * 2000) + "!")
caused catastrophic backtracking.
The fix removes ambiguity about which \s* should match a particular
space.
You can create a malicious server which responds with Set-Cookie headers
to attack all python programs which access it e.g.
from http.server import BaseHTTPRequestHandler, HTTPServer
def make_set_cookie_value(n_spaces):
spaces = " " * n_spaces
expiry = f"1-c-1{spaces}!"
return f"b;Expires={expiry}"
class Handler(BaseHTTPRequestHandler):
def do_GET(self):
self.log_request(204)
self.send_response_only(204) # Don't bother sending Server and Date
n_spaces = (
int(self.path[1:]) # Can GET e.g. /100 to test shorter sequences
if len(self.path) > 1 else
65506 # Max header line length 65536
)
value = make_set_cookie_value(n_spaces)
for i in range(99): # Not necessary, but we can have up to 100 header lines
self.send_header("Set-Cookie", value)
self.end_headers()
if __name__ == "__main__":
HTTPServer(("", 44020), Handler).serve_forever()
This server returns 99 Set-Cookie headers. Each has 65506 spaces.
Extracting the cookies will pretty much never complete.
Vulnerable client using the example at the bottom of
https://docs.python.org/3/library/http.cookiejar.html :
import http.cookiejar, urllib.request
cj = http.cookiejar.CookieJar()
opener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(cj))
r = opener.open("http://localhost:44020/")
The popular requests library was also vulnerable without any additional
options (as it uses http.cookiejar by default):
import requests
requests.get("http://localhost:44020/")
* Regression test for http.cookiejar REDoS
If we regress, this test will take a very long time.
* Improve performance of http.cookiejar.ISO_DATE_RE
A string like
"444444" + (" " * 2000) + "A"
could cause poor performance due to the 2 overlapping \s* groups,
although this is not as serious as the REDoS in LOOSE_HTTP_DATE_RE was.
is_cgi() function of http.server library does not currently handle a
cgi script if one of the cgi_directories is located at the
sub-directory of given path. Since is_cgi() in CGIHTTPRequestHandler
class separates given path into (dir, rest) based on the first seen
'/', multi-level directories like /sub/dir/cgi-bin/hello.py is divided
into head=/sub, rest=dir/cgi-bin/hello.py then check whether '/sub'
exists in cgi_directories = [..., '/sub/dir/cgi-bin'].
This patch makes the is_cgi() keep expanding dir part to the next '/'
then checking if that expanded path exists in the cgi_directories.
Signed-off-by: Siwon Kang <kkangshawn@gmail.com>
https://bugs.python.org/issue38863
Skip the test_posix.test_pidfd_open() test if os.pidfd_open() fails
with a PermissionError. This situation can happen in a Linux sandbox
using a syscall whitelist which doesn't allow the pidfd_open()
syscall yet (like systemd-nspawn).
Remove BEGIN_FINALLY, END_FINALLY, CALL_FINALLY and POP_FINALLY bytecodes. Implement finally blocks by code duplication.
Reimplement frame.lineno setter using line numbers rather than bytecode offsets.
This exposes a Linux-specific syscall for sending a signal to a process
identified by a file descriptor rather than a pid.
For simplicity, we don't support the siginfo_t parameter to the syscall. This
parameter allows implementing a pidfd version of rt_sigqueueinfo(2), which
Python also doesn't support.
When building Python in some uncommon platforms there are some known tests that will fail. Right now, the test suite has the ability to ignore entire tests using the -x option and to receive a filter file using the --matchfile filter. The problem with the --matchfile option is that it receives a file with patterns to accept and when you want to ignore a couple of tests and subtests, is too cumbersome to lists ALL tests that are not the ones that you want to accept and he problem with -x is that is not easy to ignore just a subtests that fail and the whole test needs to be ignored.
For these reasons, add a new option to allow to ignore a list of test and subtests for these situations.
Capturing exceptions into names can lead to reference cycles though the __traceback__ attribute of the exceptions in some obscure cases that have been reported previously and fixed individually. As these variables are not used anyway, we can remove the binding to reduce the chances of creating reference cycles.
See for example GH-13135
This PR implements a fix for `multiprocessing.Process` objects; the error occurs when Processes are created using either `fork` or `forkserver` as the `start_method`.
In these instances, the `MainThread` of the newly created `Process` object retains all attributes from its parent's `MainThread` object, including the `native_id` attribute. The resulting behavior is such that the new process' `MainThread` captures an incorrect/outdated `native_id` (the parent's instead of its own).
This change forces the Process object to update its `native_id` attribute during the bootstrap process.
cc @vstinner
https://bugs.python.org/issue38707
Automerge-Triggered-By: @pitrou
