[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: Alright, I've backported the fix to 3.4. Closing this. -- stage: -> resolved status: open -> closed ___ Python tracker ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: > Jim ask for a backport. Sorry Jim, was replying from my email client, didn't see all messages. > This is arguably a security issue because it's a DoS vector. Yeah, I can see why. I can commit this to 3.4 in a week. Christian, feel free to commit this if y

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: This is arguably a security issue because it's a DoS vector. I don't feel strongly about it though. -- ___ Python tracker ___ _

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Christian Heimes added the comment: Jim ask for a backport. In case the problem is not a security issue that needs to be backported, feel free to close the ticket. -- ___ Python tracker ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: Isn't 3.4 in security fixes only mode? -- status: pending -> open ___ Python tracker ___ ___ Python-

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Christian Heimes added the comment: Yuri, are you going to backport the fix to 3.4? -- assignee: -> yselivanov nosy: +christian.heimes status: open -> pending versions: -Python 3.5 ___ Python tracker

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: Yes, that change addresses this issue. Thanks! Will this be backported? -- resolution: -> fixed ___ Python tracker ___ ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: Cool, I will verify soon. -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: It looks like this was fixed by #27759!. Jim, could you please verify? -- ___ Python tracker ___ __

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Changes by Jim Fulton : -- type: behavior -> security ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://m

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: > It also doesn't occur with uvloop, which I assume still uses sockets. No, uvloop doesn't use python sockets or select for IO at all. All IO is done in libuv. > WRT CPython/sockets this problem doesn't happen if I use asyncore to accept > connections and ha

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: WRT CPython/sockets this problem doesn't happen if I use asyncore to accept connections and hand them off to create_connection. :) It also doesn't occur with uvloop, which I assume still uses sockets. Also, FWIW, the relevant ZEO test passes if I use SSL, which is

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Guido van Rossum added the comment: No, I just don't have a computer right now, only a phone. --Guido (mobile) -- ___ Python tracker ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: Running out of time to debug this today. I think this is a bug in CPython, in either socket or select module. When I inject some debug code in selectors.py and replace KQueue with select(), I can see that the server thread's selector stops working at some po

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: Yuri, right you are. Thanks. Марк, see https://bugs.launchpad.net/zodb/+bug/135108/comments/9 -- ___ Python tracker ___ ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: Guido, are you saying that the script runs without hanging for you? (If you get a boatload of tracebacks, that's due to another asyncio bug in error handling.) Are you running the version with prints? This is an adaptation of the echo server and client from the do

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Yury Selivanov added the comment: Jim, I think you wanted to post this link in this issue: https://bugs.launchpad.net/zodb/+bug/135108/comments/9 instead of in #27392. I can reproduce this on my mac, but so far I've no idea what's going on. -- ___ P

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Guido van Rossum added the comment: I can't personally run that code and get the results you are getting; could you please walk us through what happens (as far as you can tell)? Reading the code I find myself quite confused about which parts of the code might be active or not. E.g. is self.mes

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: Here's a version sans prints -- Added file: http://bugs.python.org/file43581/echo-no-print.py ___ Python tracker ___ ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Марк Коренберг added the comment: One more thing. Why you set socket.SO_LINGER ? and why lingering timeout is 0 seconds ? Removing that eliminate problem completely. -- ___ Python tracker

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: OK, I *was* able to simplify it a fair bit. I'm uploading a new version. I left prints in because I think you'd find them helpful, but I'll upload another version without prints. -- Added file: http://bugs.python.org/file43580/echo.py ___

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Changes by Jim Fulton : Removed file: http://bugs.python.org/file43540/echo.py ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubs

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Марк Коренберг added the comment: Also I recommend you to use asyncio streams, instead of reinventing wheels. So, reading your command will look like: data = await stream.read_exactly(4) (len,) = unpack(">I", data) command = await stream.read_exactly(len) -- __

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Марк Коренберг added the comment: Plese reduce even more. I mean remove debugging, specifi commands, and all extra code, that is not related to original problem. -- ___ Python tracker _

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: This is already pretty minimal. There are no external dependencies. -- ___ Python tracker ___ ___ Python

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Guido van Rossum added the comment: Yeah, I'd like to see a more minimal repro to understand what's going in. -- ___ Python tracker ___ __

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Марк Коренберг added the comment: Please reduce program, and make sure it still hangs. -- nosy: +mmarkk ___ Python tracker ___ ___ Pyt

[issue27386] Asyncio server hang when clients connect and immediately disconnect

Jim Fulton added the comment: FWIW, using uvloop avoids the hang. -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscr

[issue27386] Asyncio server hang when clients connect and immediately disconnect

New submission from Jim Fulton: I recently ported ZEO to asyncio. We'd had a bug in our old asyncore-based server where the server would hang if several connections were made and then immediately disconnected on Mac OS X. This was due to an error-handling bug in our code that we fixed. We ha