RFR (S): 8238676: jni crashes on accessing it from process exit hook

[gerard ziemski]

hi David,

On 2/18/20 8:04 PM, David Holmes wrote:
> Bug: https://bugs.openjdk.java.net/browse/JDK-8238676
> webrev: http://cr.openjdk.java.net/~dholmes/8238676/webrev/
>
> If an application tries to use JNI from an atexit handler, the attempt 
> can't succeed (the VM has already logically terminated) but it should 
> not crash. The JNI Invocation API code was missing some checks in 
> places and wasn't aware of the possibility of trying to make calls 
> from the VMThread.
>
> Testing:
>  - new test added for the JNI Invocation API
>  - tiers 1-3
>
> Thanks,
> David

In jni_GetEnv() we have:

4120   if (vm_created == 0) {
4121     *penv = NULL;
4122     ret = JNI_EDETACHED;
4123     return ret;
4124   }

but in jni_DetachCurrentThread() we have:

4063   if (vm_created == 0) {
4064     HOTSPOT_JNI_DETACHCURRENTTHREAD_RETURN(JNI_ERR);
4065     return JNI_ERR;
4066   }

should lines 4064,4065 perhaps be:

4064     HOTSPOT_JNI_DETACHCURRENTTHREAD_RETURN(JNI_EDETACHED);
4065     return JNI_EDETACHED;

to be consistent?

Looks good otherwise.


cheers