[zeromq-dev] Open file leak during DNS resolution while network is down (regression in libzmq-4.1.0 and libzmq-master) #1302

[Tomas Krajca]

Hi, I have hit this "old" issue again with the latest master 
https://github.com/zeromq/libzmq/commit/6b4d9bca0c31fc8131749396fd996d17761c999f 
and a couple of weeks old master 
https://github.com/zeromq/libzmq/commit/1a5ced9f474edbb33c39a65fdb62c0a1e87e32ca. 
I am pretty sure it has been fixed after the first regression but it 
must have somehow got back into the master at some point. Can anybody 
else confirm this?

Thanks,
Tomas

On 01/29/2015 10:28 AM, Tomas Krajca wrote:
> Hi,
>
> Sorry, I didn't have time to retest it properly. Just close it and I
> will reopen it if I can reproduce it against the latest master.
>
> Thanks,
> Tomas
>
> On 01/28/2015 10:00 PM, zeromq-dev-request at lists.zeromq.org wrote:
>> Date: Tue, 27 Jan 2015 11:46:19 -0600
>> From: Thomas Rodgers<rodgert at twrodgers.com>
>> Subject: Re: [zeromq-dev] Open file leak during DNS resolution while
>>     network is down (regression in libzmq-4.1.0 and libzmq-master) #1302
>> To: ZeroMQ development list<zeromq-dev at lists.zeromq.org>
>> Message-ID:
>>     <CAAB_aXtZqB7D=ABWXALr0ydS4Z=wq8qeW5hf1ghbbemwVop1-Q at mail.gmail.com>
>> Content-Type: text/plain; charset="utf-8"
>>
>> Is it safe to close issue #1302
>> <https://github.com/zeromq/libzmq/issues/1302>  now?
>>
>> On Wed, Jan 21, 2015 at 8:13 PM, Tomas Krajca<tomas at repositpower.com>
>> wrote:
>>
>>> >Hi Thomas,
>>> >
>>> >I can't reproduce the error against the latest libzmq trunk either. It
>>> >must have been fixed fairly recently because we tested this with the
>>> >latest libzmq trunk as of Friday last week or whenever it was. I would
>>> >be curious to see how it got fixed but I can't quite find the right
>>> commit.
>>> >
>>> >I'll do some more testing on this one but it seems good.
>>> >
>>> >Cheers,
>>> >Tomas
>>> >
>>> >On 01/21/2015 10:00 PM,zeromq-dev-request at lists.zeromq.org  wrote:
>>>> > >I'm running your sample against current libzmq trunk, Ubuntu
>>>> 14.04 and I
>>> >am
>>>> > >unable to reproduce any leak.
>>>> > >
>>>> > >On Tue, Jan 20, 2015 at 2:08 AM, Pieter Hintjens<ph at imatix.com>
>>>> wrote:
>>>> > >
>>>>>> > >> >OK, thanks for the simple test case.
>>>>>> > >> >
>>>>>> > >> >I'm not familiar enough with the internals of libzmq to
>>>>>> debug this. I
>>>>>> > >> >see that tcp_connecter.cpp is closing the socket if it can't
>>>>>> resolve
>>>>>> > >> >the hostname. However it's possible some error handling
>>>>>> isn't right
>>>>>> > >> >here.
>>>>>> > >> >
>>>>>> > >> >
>>>>>> > >> >On Tue, Jan 20, 2015 at 5:04 AM, Tomas
>>>>>> Krajca<tomas at repositpower.com>
>>>>>> > >> >wrote:
>>>>>>>> > >>> > >Hi Peter,
>>>>>>>> > >>> > >
>>>>>>>> > >>> > >It's actually really simple, I have posted example C
>>>>>>>> code to github
>>> >at
>>>>>>>> > >>> > >https://github.com/zeromq/libzmq/issues/1302. Am I
>>>>>>>> doing something
>>> >wrong
>>>>>>>> > >>> > >or is it that obvious?
>>>>>>>> > >>> > >
>>>>>>>> > >>> > >There is no need for a poller or anything like that. It
>>>>>>>> seems that
>>> >DNS
>>>>>>>> > >>> > >resolution during zmq_connect() somehow does not
>>>>>>>> release the file
>>> >handle
>>>>>>>> > >>> > >if network is down.
>>>>>>>> > >>> > >
>>>>>>>> > >>> > >Cheers,
>>>>>>>> > >>> > >Tomas
>>>>>>>> > >>> > >
>>>>>>>>>> > >>>> > >>Message: 19
>>>>>>>>>> > >>>> > >>Date: Mon, 19 Jan 2015 10:32:47 +0100
>>>>>>>>>> > >>>> > >>From: Pieter Hintjens<ph at imatix.com>
>>>>>>>>>> > >>>> > >>Subject: Re: [zeromq-dev] Open file leak during DNS
>>>>>>>>>> resolution
>>> >while
>>>>>>>>>> > >>>> > >>       network is down (regression in libzmq-4.1.0 and
>>> >libzmq-master)
>>>>>> > >> >#1302
>>>>>>>>>> > >>>> > >>To: ZeroMQ development
>>>>>>>>>> list<zeromq-dev at lists.zeromq.org>
>>>>>>>>>> > >>>> > >>Cc: Mark Burgess<mark at repositpower.com>
>>>>>>>>>> > >>>> > >>Message-ID:
>>>>>>>>>> > >>>> > >>       <CADL5_shw3B+0YN4MYVCROEwufeH6_ThvxDKcw5c=
>>>>>> > >> >vkfo4Dw5ew at mail.gmail.com>
>>>>>>>>>> > >>>> > >>Content-Type: text/plain; charset=UTF-8
>>>>>>>>>> > >>>> > >>
>>>>>>>>>> > >>>> > >>Can your C++ programmer make a minimal test case in
>>>>>>>>>> C that
>>> >reproduces
>>>>>>>>>> > >>>> > >>the problem?
>>>>>>>>>> > >>>> > >>
>>>>>>>>>> > >>>> > >>On Mon, Jan 19, 2015 at 1:55 AM, Tomas Krajca<
>>> >tomas at repositpower.com>
>>>>>> > >> >wrote:
>>>>>>>>>>>> > >>>>> > >>>Hi,
>>>>>>>>>>>> > >>>>> > >>>
>>>>>>>>>>>> > >>>>> > >>>I've reported this weird bug
>>>>>> > >> >https://github.com/zeromq/libzmq/issues/1302
>>>>>>>>>>>> > >>>>> > >>>that we hit last week, I wonder if anybody
>>>>>>>>>>>> experienced the same
>>> >thing
>>>>>> > >> >or can
>>>>>>>>>>>> > >>>>> > >>>reproduce it. Basically, we saw a progressive
>>>>>>>>>>>> file handle leak
>>> >that
>>>>>> > >> >crashed
>>>>>>>>>>>> > >>>>> > >>>our application after about an hour of network
>>>>>>>>>>>> outage.
>>>>>>>>>>>> > >>>>> > >>>
>>>>>>>>>>>> > >>>>> > >>>Any thoughts of which part of the code could
>>>>>>>>>>>> the bug be in?
>>> >We've got
>>>>>> > >> >a C++
>>>>>>>>>>>> > >>>>> > >>>programmer in our team but don't know enough
>>>>>>>>>>>> about libzmq
>>> >internals to
>>>>>> > >> >try
>>>>>>>>>>>> > >>>>> > >>>to fix this.
>>>>>>>>>>>> > >>>>> > >>>
>>>>>>>>>>>> > >>>>> > >>>Thanks,
>>>>>>>>>>>> > >>>>> > >>>Tomas
>>> >_______________________________________________
>>> >zeromq-dev mailing list
>>> >zeromq-dev at lists.zeromq.org
>>> >http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>>> >