Code Review Request, JDK-8219991 : New fix of the deadlock in sun.security.ssl.SSLSocketImpl

[Daniel Fuchs]

Hi Xuelei,

I believe there is still a small window of opportunity
for which `readLockedDeplete();` will never be called.

The issue is in `deplete()`:

If tryLock() fails to lock at line
1046             if (readLock.tryLock()) {
then there's no guarantee that the reading
thread will not release the readLock before
the else { } statement is executed at line:
1054                 isClosing = true;

Thread 1:  enters `read`, locks `readLock`
Thread 2:  enters `deplete`, fails to lock
Thread 1:  finishes reading, find `isClosing` is false,
            releases `readLock`.
Thread 2:  `deplete` sets `isClosing` to true and returns

then any further call to `read` will find `isClosing == true`
and return EOF.

If that happens and I'm not mistaken, then
`readLockedDeplete();` will never be called.

best regards,

-- daniel



On 02/05/2019 21:11, Xuelei Fan wrote:
> Hi,
> 
> Could I get the following update reviewed?
> 
>     http://cr.openjdk.java.net/~xuelei/8219991/webrev.00/
> 
> The March5 test looks good, and the external test described in 
> JDK-8219658 passed.  No new regression test.
> 
> Thanks,
> Xuelei