RFR (XXXS): 8193234: When using -Xcheck:jni an internally allocated buffer can leak

[David Holmes]

Updated webrev:

http://cr.openjdk.java.net/~dholmes/8193234/webrev.v2/

Can I get a second review please.

Thanks,
David

On 8/02/2019 8:59 am, David Holmes wrote:
> Hi Aleksey,
> 
> Thanks for looking at this.
> 
> On 8/02/2019 1:53 am, Aleksey Shipilev wrote:
>> On 2/7/19 11:13 AM, David Holmes wrote:
>>> bug: https://bugs.openjdk.java.net/browse/JDK-8193234
>>> webrev: http://cr.openjdk.java.net/~dholmes/8193234/webrev
>>
>> The patch looks good.
>>
>>> Full details in bug report but basically with the use of 
>>> GuardedMemory in the checked versions of
>>> the *ArrayCritical functions we always have to release the 
>>> GuardedMemory copy.
>>
>> Ah, oops. It seems fine to free the copy of guarded memory 
>> unconditionally. While you are at it,
>> switch statement can also be simplified by coalescing case labels. It 
>> also makes the dichotomy
>> between "normal" and "abort" paths evident:
>>
>>    switch (mode) {
>>    case 0:
>>    case JNI_COMMIT:
>>      memcpy(orig_result, carray, sz);
>>      break;
>>    case JNI_ABORT:
>>      break;
>>    default:
>>      ...
>>    }
> 
> The coalescing is only possible because we never uses copies and so 
> never have to free them - which is the difference between modes 0 and 
> JNI_COMMIT. But I can do that and add a clarifying comment.
> 
> Thanks,
> David
> 
>> -Aleksey
>>