** Description changed: - Occurs in the version 3.6 of aiohttp (present currently in focal). - When cancelling a connector task, the associated resolver task (if not - finished) is not cancelled and continues running. + [Impact] + + * When cancelling a connector task, the associated resolver task (if + not finished) is not cancelled and continues running. Unfortunately, if the resolver task eventually raises an exception (e.g., socket.gaierror), the exception will go directly to the exception handler because none will be awaiting the task anymore. - This is the root cause of https://bugs.launchpad.net/ubuntu-power- - systems/+bug/1969393 + This results in applications crashing with exceptions such as: - The fix on aiohttp was backported to 3.7 but not to 3.6. + Task exception was never retrieved + future: <Task finished name='Task-3' coro=<TCPConnector._resolve_host() done, defined at /usr/lib/python3/dist-packages/aiohttp/connector.py:774> exception=gaierror(-2, 'Name or service not known')> + Traceback (most recent call last): + File "/usr/lib/python3/dist-packages/aiohttp/connector.py", line 829, in _resolve_host + addrs = await \ + File "/usr/lib/python3/dist-packages/aiohttp/resolver.py", line 29, in resolve + infos = await self._loop.getaddrinfo( + File "/usr/lib/python3.8/asyncio/base_events.py", line 825, in getaddrinfo + return await self.run_in_executor( + File "/usr/lib/python3.8/concurrent/futures/thread.py", line 57, in run + result = self.fn(*self.args, **self.kwargs) + File "/usr/lib/python3.8/socket.py", line 918, in getaddrinfo + for res in _socket.getaddrinfo(host, port, family, type, proto, flags): + socket.gaierror: [Errno -2] Name or service not known + + * This aiohttp bug is the root cause of a crash in Subiquity: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1969393 + Currently, we build the Subiquity snap based on deb packages (including python3-aiohttp) from focal. We temporarily moved from python3-aiohttp to python3-requests in Subiquity to work around this crash. + * Other applications based on python3-aiohttp can be affected and crash despite the absence of other bug reports. + + * The patch in the debdiff makes sure that resolver tasks end up being + awaited when the associated connector tasks gets cancelled. + + [Test Plan] + + * The following chunk of code can be executed to reproduce the issue: https://paste.ubuntu.com/p/XrnfqVHtBh/ (it takes ~60 seconds to execute). + + * On python3-aiohttp 3.6 (focal), the exception handler wakes up with: + + Task exception was never retrieved + future: <Task finished name='Task-3' coro=<TCPConnector._resolve_host() done, defined at /usr/lib/python3/dist-packages/aiohttp/connector.py:774> exception=gaierror(-2, 'Name or service not known')> + + * When aiohttp is patched, nothing should happens. + + * Manually testing the patched library against Subiquity to make sure it solves https://bugs.launchpad.net/ubuntu-power-systems/+bug/1969393. + This was done on my end using this PPA: https://launchpad.net/~ogayot/+archive/ubuntu/focal-bugfix . Tests were green. + + [Where problems could occur] + + * Since the patch affects a python library, any application that + depends on this library (aka. python3-aiohttp) on focal would be + affected by the upload. + + * In the unlikely event that this patch introduces a regression, + applications that depend on python3-aiohttp (i.e., in focal/universe) + can crash or raise exceptions. + + * If any package in focal/main has python3-aiohttp as a Build-Depends, a regression could cause said package to FTBFS. + + [Other Info] + + * The debdiff brings a backport of an upstream patch that is present in aiohttp 3.7 and newer versions: https://github.com/aio-libs/aiohttp/pull/5050
** Description changed: + [Impact] - [Impact] - - * When cancelling a connector task, the associated resolver task (if + * When cancelling a connector task, the associated resolver task (if not finished) is not cancelled and continues running. Unfortunately, if the resolver task eventually raises an exception (e.g., socket.gaierror), the exception will go directly to the exception handler because none will be awaiting the task anymore. This results in applications crashing with exceptions such as: Task exception was never retrieved future: <Task finished name='Task-3' coro=<TCPConnector._resolve_host() done, defined at /usr/lib/python3/dist-packages/aiohttp/connector.py:774> exception=gaierror(-2, 'Name or service not known')> Traceback (most recent call last): - File "/usr/lib/python3/dist-packages/aiohttp/connector.py", line 829, in _resolve_host - addrs = await \ - File "/usr/lib/python3/dist-packages/aiohttp/resolver.py", line 29, in resolve - infos = await self._loop.getaddrinfo( - File "/usr/lib/python3.8/asyncio/base_events.py", line 825, in getaddrinfo - return await self.run_in_executor( - File "/usr/lib/python3.8/concurrent/futures/thread.py", line 57, in run - result = self.fn(*self.args, **self.kwargs) - File "/usr/lib/python3.8/socket.py", line 918, in getaddrinfo - for res in _socket.getaddrinfo(host, port, family, type, proto, flags): + File "/usr/lib/python3/dist-packages/aiohttp/connector.py", line 829, in _resolve_host + addrs = await \ + File "/usr/lib/python3/dist-packages/aiohttp/resolver.py", line 29, in resolve + infos = await self._loop.getaddrinfo( + File "/usr/lib/python3.8/asyncio/base_events.py", line 825, in getaddrinfo + return await self.run_in_executor( + File "/usr/lib/python3.8/concurrent/futures/thread.py", line 57, in run + result = self.fn(*self.args, **self.kwargs) + File "/usr/lib/python3.8/socket.py", line 918, in getaddrinfo + for res in _socket.getaddrinfo(host, port, family, type, proto, flags): socket.gaierror: [Errno -2] Name or service not known - * This aiohttp bug is the root cause of a crash in Subiquity: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1969393 + * This aiohttp bug is the root cause of a crash in Subiquity: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1969393 Currently, we build the Subiquity snap based on deb packages (including python3-aiohttp) from focal. We temporarily moved from python3-aiohttp to python3-requests in Subiquity to work around this crash. - * Other applications based on python3-aiohttp can be affected and crash despite the absence of other bug reports. + * Other applications based on python3-aiohttp can be affected and crash despite the absence of other bug reports. - * The patch in the debdiff makes sure that resolver tasks end up being + * The patch in the debdiff makes sure that resolver tasks end up being awaited when the associated connector tasks gets cancelled. [Test Plan] - * The following chunk of code can be executed to reproduce the issue: https://paste.ubuntu.com/p/XrnfqVHtBh/ (it takes ~60 seconds to execute). - - * On python3-aiohttp 3.6 (focal), the exception handler wakes up with: + * The following chunk of code can be executed to reproduce the issue: + https://paste.ubuntu.com/p/XrnfqVHtBh/ (it takes ~60 seconds to + execute). - Task exception was never retrieved - future: <Task finished name='Task-3' coro=<TCPConnector._resolve_host() done, defined at /usr/lib/python3/dist-packages/aiohttp/connector.py:774> exception=gaierror(-2, 'Name or service not known')> - - * When aiohttp is patched, nothing should happens. + * On python3-aiohttp 3.6 (focal), the exception handler wakes up + with: - * Manually testing the patched library against Subiquity to make sure it solves https://bugs.launchpad.net/ubuntu-power-systems/+bug/1969393. + Task exception was never retrieved + future: <Task finished name='Task-3' coro=<TCPConnector._resolve_host() done, defined at /usr/lib/python3/dist-packages/aiohttp/connector.py:774> exception=gaierror(-2, 'Name or service not known')> + + * When aiohttp is patched, nothing should happens. + + * Manually testing the patched library against Subiquity to make sure it solves https://bugs.launchpad.net/ubuntu-power-systems/+bug/1969393. This was done on my end using this PPA: https://launchpad.net/~ogayot/+archive/ubuntu/focal-bugfix . Tests were green. [Where problems could occur] - * Since the patch affects a python library, any application that + * Since the patch affects a python library, any application that depends on this library (aka. python3-aiohttp) on focal would be affected by the upload. - * In the unlikely event that this patch introduces a regression, + * In the unlikely event that this patch introduces a regression, applications that depend on python3-aiohttp (i.e., in focal/universe) can crash or raise exceptions. - * If any package in focal/main has python3-aiohttp as a Build-Depends, a regression could cause said package to FTBFS. - + * If any package in focal/main has python3-aiohttp as a Build-Depends, + a regression could cause said package to FTBFS. + [Other Info] - - * The debdiff brings a backport of an upstream patch that is present in aiohttp 3.7 and newer versions: + + * The debdiff brings a backport of an upstream patch that is present in + aiohttp 3.7 and newer versions: https://github.com/aio-libs/aiohttp/pull/5050 + + * Upstream bug report: https://github.com/aio-libs/aiohttp/issues/4330 ** Changed in: python-aiohttp (Ubuntu) Status: Incomplete => New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1969817 Title: Uncaught exception when connector is cancelled To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/python-aiohttp/+bug/1969817/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
