diff options
| -rw-r--r-- | Lib/multiprocessing/connection.py | 5 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Security/2022-09-07-10-42-00.gh-issue-97514.Yggdsl.rst | 15 |
2 files changed, 15 insertions, 5 deletions
diff --git a/Lib/multiprocessing/connection.py b/Lib/multiprocessing/connection.py index 510e4b5..8e2facf 100644 --- a/Lib/multiprocessing/connection.py +++ b/Lib/multiprocessing/connection.py @@ -73,11 +73,6 @@ def arbitrary_address(family): if family == 'AF_INET': return ('localhost', 0) elif family == 'AF_UNIX': - # Prefer abstract sockets if possible to avoid problems with the address - # size. When coding portable applications, some implementations have - # sun_path as short as 92 bytes in the sockaddr_un struct. - if util.abstract_sockets_supported: - return f"\0listener-{os.getpid()}-{next(_mmap_counter)}" return tempfile.mktemp(prefix='listener-', dir=util.get_temp_dir()) elif family == 'AF_PIPE': return tempfile.mktemp(prefix=r'\\.\pipe\pyc-%d-%d-' % diff --git a/Misc/NEWS.d/next/Security/2022-09-07-10-42-00.gh-issue-97514.Yggdsl.rst b/Misc/NEWS.d/next/Security/2022-09-07-10-42-00.gh-issue-97514.Yggdsl.rst new file mode 100644 index 0000000..02d95b5 --- /dev/null +++ b/Misc/NEWS.d/next/Security/2022-09-07-10-42-00.gh-issue-97514.Yggdsl.rst @@ -0,0 +1,15 @@ +On Linux the :mod:`multiprocessing` module returns to using filesystem backed +unix domain sockets for communication with the *forkserver* process instead of +the Linux abstract socket namespace. Only code that chooses to use the +:ref:`"forkserver" start method <multiprocessing-start-methods>` is affected. + +Abstract sockets have no permissions and could allow any user on the system in +the same `network namespace +<https://man7.org/linux/man-pages/man7/network_namespaces.7.html>`_ (often the +whole system) to inject code into the multiprocessing *forkserver* process. +This was a potential privilege escalation. Filesystem based socket permissions +restrict this to the *forkserver* process user as was the default in Python 3.8 +and earlier. + +This prevents Linux `CVE-2022-42919 +<https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-42919>`_. |