Previous fix was more elegant.
In fact, I do not like new one.

Thanks,
Serguei

On 7/25/14 6:04 AM, Jaroslav Bachorik wrote:
On 07/25/2014 01:40 PM, Dmitry Samersoff wrote:
Jaroslav,

readProviderData already use CHECK

So it might be better to:

1. change readProviderData to return 0 on error and 1 on success.

2. add check for exception to ll 201 and abort the loop if at least
    one of providers is not read.

Ok, here is another attempt, now without introducing a new function.

http://cr.openjdk.java.net/~jbachorik/8030115/webrev.01

-JB-



-Dmitry


On 2014-07-24 15:07, Jaroslav Bachorik wrote:
Please, review the change for the fix of the following problem

In jdk/src/share/native/sun/tracing/dtrace/JVM.c the following code is
invoked in loop

198     for (i = 0; i < num_providers; ++i) {
199         JVM_DTraceProvider* p = &(jvm_providers[i]);
200         jobject provider = (*env)->GetObjectArrayElement(
201             env, providers, i);
202         readProviderData(env, provider, p);
203     }

The first problem is that GetGetObjectArrayElement() call on L200 may
throw an exception which is not checked subsequently. On L202 the call
to readProviderData() can also raise a Java exception without
appropriate after-check. When getting back to the beginning of the loop
GetObjectArrayElement() may be called with a pending exception which is
deemed unsafe.

The fix extracts the inner part of the loop into a separate function
where the result of each step is properly checked for pending
exceptions. If there is a pending exception the loop will be
interrupted, resources cleaned and
Java_sun_tracing_dtrace_JVM_activate0() function will return 0 with the
pending exception recorded in env.


Webrev: http://cr.openjdk.java.net/~jbachorik/8030115/webrev.00

Thanks,

-JB-




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