RFR [8022584] Memory leak in some NetworkInterface methods

[Ivan Gerasimov]

Hello Chris!

Here's the update:
http://cr.openjdk.java.net/~igerasim/8022584/2/webrev/

Thanks for offering the sponsorship!
Here's the hg-export
http://cr.openjdk.java.net/~igerasim/2commit/8022584-jdk8-Memleak-in-NetworkInterface.patch

Sincerely yours,
Ivan

On 08.08.2013 12:43, Chris Hegarty wrote:
> Thanks for taking this Ivan.
>
> Can you please make the changes suggested by both David and Alan ( 
> simply return NULL/-1/JNI_FALSE, as appropriate, if GetStringUTFChars 
> fails ( returns NULL ), then I will sponsor this change into jdk8 for 
> you.
>
> Please post an update webrev to cr.openjdk.java.net.
>
> -Chris.
>
> On 08/08/2013 06:01 AM, David Holmes wrote:
>> Ivan,
>>
>> On 8/08/2013 2:05 PM, Ivan Gerasimov wrote:
>>> David, Alan,
>>>
>>> I added checking for NULL  results and throwing OOMException if
>>> necessary.
>>
>> You don't need to throw it yourself:
>>
>>    JNU_ThrowOutOfMemoryError(env, NULL);
>>
>> Assuming a correct VM implementation if NULL is returned then an OOME
>> should already be pending and will be thrown as soon as your native code
>> returns to Java.
>>
>> Thanks,
>> David
>>
>>> I've also added some spaces along the code to improve indentation.
>>>
>>> Would you please review the updated webrev?
>>> http://washi.ru.oracle.com/~igerasim/webrevs/8022584/1/webrev/
>>>
>>> Sincerely yours,
>>> Ivan
>>>
>>>
>>> On 08.08.2013 5:35, David Holmes wrote:
>>>> On 8/08/2013 11:20 AM, Ivan Gerasimov wrote:
>>>>> Thanks Alan!
>>>>>
>>>>> I've checked that and it turns out that GetStringUTFChars cannot 
>>>>> return
>>>>> NULL.
>>>>> For allocation of the result string it calls AllocateHeap() with the
>>>>> default EXIT_OOM fail strategy.
>>>>> Thus, in case of being unable to allocate memory it simply stops VM.
>>>>
>>>> Ouch! That is a hotspot bug. GetStringUTFChars is supposed to throw
>>>> OutOfMemoryError if it has memory issues, not abort the VM!
>>>>
>>>> I recommend that you check for NULL and/or a pending exception.
>>>>
>>>> David
>>>>
>>>>> Sincerely yours,
>>>>> Ivan
>>>>>
>>>>> On 08.08.2013 5:05, Alan Bateman wrote:
>>>>>> (cc'ing net-dev).
>>>>>>
>>>>>> The change looks okay to me. One suggestion (while you are there) is
>>>>>> to check the return from  GetStringUTFChars so that the name returns
>>>>>> when it fails with NULL.
>>>>>>
>>>>>> -Alan.
>>>>>>
>>>>>> On 07/08/2013 17:46, Ivan Gerasimov wrote:
>>>>>>> Hello everybody!
>>>>>>>
>>>>>>> Some methods of NetworkInterface class were reported to leak 
>>>>>>> memory.
>>>>>>> http://bugs.sun.com/view_bug.do?bug_id=JDK-8022584 (not yet
>>>>>>> available.)
>>>>>>>
>>>>>>> Examples are isUp() and isLoopback().
>>>>>>>
>>>>>>> Affected versions of jdk are 6, 7 and 8
>>>>>>>
>>>>>>> Would you please review a simple fix that removes the unnecessary
>>>>>>> allocation?
>>>>>>> http://cr.openjdk.java.net/~igerasim/8022584/0/webrev/
>>>>>>>
>>>>>>> Sincerely yours,
>>>>>>> Ivan
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>
>
>