Again, I am not sure why you are focusing on the race condition.  Race 
condition is not the problem. Fact that grpc decides to put some global 
callbacks on the OpenSSL is the problem. It should not do that. Why can't 
this be made optional via a compile time flag or some run time 
initialization parameter?

On Wednesday, April 18, 2018 at 3:52:47 PM UTC-7, Jiangtao Li wrote:
>
> I don't see a convenient way to do in gRPC. SSL init can be called 
> multiple times, as long as it is not called in the same time. It seems that 
> the best way to address is adding mutex in your application to make sure 
> SSL init is not called simultaneously. 
>
> On Wed, Apr 18, 2018 at 3:28 PM Arpit Baldeva <[email protected] 
> <javascript:>> wrote:
>
>>
>> Yes, there are two parallel threads that do this at the same time. What I 
>> was noticing is that at application shutdown, my application complained 
>> about the lock I handed over to OpenSSL not being unlocked. Looking into 
>> it, I realized that during initialization, OpenSSL grabbed a lock from my 
>> callback, during this time, grpc replaced the locks and OpenSSL unlock call 
>> got re-routed. But again, this is just a side effect. The real problem is 
>> simply the fact that grpc is setting some global callbacks on OpenSSL that 
>> should best be left to the application. I understand that this is probably 
>> done to make it easy for the grpc integrators but there are applications 
>> such as mine where there are other usage of OpenSSL and I'd rather manage 
>> the global settings myself than rely on grpc to do it.
>>
>>
>>
>> On Wednesday, April 18, 2018 at 3:05:05 PM UTC-7, [email protected] 
>> wrote:
>>>
>>> Could you describe the race condition in details?
>>>
>>> In gRPC ssl_transport_security, init_openssl() is only called when ssl 
>>> transport security is needed. In your application, you are 
>>> calling SSL_library_init() in a separate thread in parallel?
>>>
>>>
>>> On Wednesday, April 18, 2018 at 2:46:28 PM UTC-7, Arpit Baldeva wrote:
>>>>
>>>> I am using grpc-1.10.0 and it has that code. Looking at the latest 
>>>> master, it still has that code - 
>>>> https://github.com/grpc/grpc/blob/master/src/core/tsi/ssl_transport_security.cc
>>>>  
>>>> - see the init_openssl function. 
>>>>
>>>> The problem is not just that grpc_init initialized the OpenSSL. The 
>>>> problem is really that grpc is initializing OpenSSL internally and it can 
>>>> trounce the application settings. Grpc should let application choose if 
>>>> they want it to handle the OpenSSL initialization or not. 
>>>>
>>>> Thanks. 
>>>>
>>>> On Wednesday, April 18, 2018 at 12:25:58 PM UTC-7, [email protected] 
>>>> wrote:
>>>>>
>>>>> Hi Arpit,
>>>>>
>>>>> grpc_init initializes OpenSSL for a short period (~2 days) and the 
>>>>> code was later removed. Do you still the problem, if you fetch the latest 
>>>>> master?
>>>>>
>>>>> On Monday, April 16, 2018 at 2:22:32 PM UTC-7, Arpit Baldeva wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I recently pinned down a sporadic race condition in my application 
>>>>>> due to grpc intializing OpenSSL internally. The problem is that OpenSSL 
>>>>>> has 
>>>>>> some global callbacks that grpc is trying to initialize on it's own 
>>>>>> without 
>>>>>> the authorization of the application. The problem is in the 
>>>>>> init_openssl call in ssl_transport_security.cc which trounces similar 
>>>>>> calls from the application. The situation is made worse(race condition) 
>>>>>> if 
>>>>>> some application threads already have locks acquired via previous calls 
>>>>>> and 
>>>>>> then grpc changes the stuff underneath before the locks are released 
>>>>>> (hence 
>>>>>> the race condition). 
>>>>>>
>>>>>> My application has usage of OpenSSL in a wider context than just 
>>>>>> grpc. I get the point that grpc is wrapping this up to make it easier 
>>>>>> for 
>>>>>> standing up an application with grpc but I think such type of things 
>>>>>> should 
>>>>>> be accompanied by a compile/run time option supplied at grpc_init that 
>>>>>> let's application decide the right owner. I am fine with the option 
>>>>>> defaulting to grpc initializing the OpenSSL internally. 
>>>>>>
>>>>>> Thoughts?
>>>>>>
>>>>>> Thanks.
>>>>>>
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