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v0.5.1
https://github.com/python/cpython
Revision d5aeccf9767c1619faa29e8ed61c93bde7bc5e3f authored by Victor Stinner on 31 August 2014, 13:07:57 UTC, committed by Victor Stinner on 31 August 2014, 13:07:57 UTC
There is a race condition in create_connection() used with wait_for() to have a
timeout. sock_connect() registers the file descriptor of the socket to be
notified of write event (if connect() raises BlockingIOError). When
create_connection() is cancelled with a TimeoutError, sock_connect() coroutine
gets the exception, but it doesn't unregister the file descriptor for write
event. create_connection() gets the TimeoutError and closes the socket.

If you call again create_connection(), the new socket will likely gets the same
file descriptor, which is still registered in the selector. When sock_connect()
calls add_writer(), it tries to modify the entry instead of creating a new one.

This issue was originally reported in the Trollius project, but the bug comes
from Tulip in fact (Trollius is based on Tulip):
https://bitbucket.org/enovance/trollius/issue/15/after-timeouterror-on-wait_for

This change fixes the race condition. It also makes sock_connect() more
reliable (and portable) is sock.connect() raises an InterruptedError.
1 parent 41f3c3f
History
Tip revision: d5aeccf9767c1619faa29e8ed61c93bde7bc5e3f authored by Victor Stinner on 31 August 2014, 13:07:57 UTC
asyncio, Tulip issue 205: Fix a race condition in BaseSelectorEventLoop.sock_connect()
Tip revision: d5aeccf

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