RFR(xs): 8224485: Crash in Exceptions::log_exception() due erroneous copying of stringStream

[Thomas Stüfe]

Please ignore this mail. I decided to fold this issue into
https://bugs.openjdk.java.net/browse/JDK-8224487 and provide a single fix.

Cheers, Thomas

On Tue, May 21, 2019 at 3:07 PM Thomas Stüfe <thomas.stuefe at gmail.com>
wrote:

> Hi all,
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8224485
> cr:
> http://cr.openjdk.java.net/~stuefe/webrevs/8224485-exceptions_log_exception_do_not_copy_stringstream/webrev.00/webrev/
>
> (Yet unpushed) JDK-8224193 uncovered a bug in Exceptions::log_exception().
> Stream object argument is handed down by value:
>
> void Exceptions::log_exception(Handle exception, stringStream tempst);
>
> which creates a copy which shares the internal backing buffer with the
> original one frame upstairs. Worked out of accident before when backing
> buffer was allocated in resource area, but since with JDK-8224193, it is
> allocated via C-heap which leads to a double free.
>
> Thanks, Thomas
>