Theoretical data race on java.util.logging.Handler.sealed

[Mandy Chung]

On 12/14/2013 9:38 AM, Peter Levart wrote:
> Hi,
>
> Daniel reminded me of a couple of issues the 4th revision of the patch 
> would have when backporting to 7u. So here's another variant that 
> tries to be more backport-friendly:
>
> http://cr.openjdk.java.net/~plevart/jdk8-tl/jul.Handler.sealed/webrev.05/

This looks good in general.

SocketHandler line 200 - it looks to me that this is an existing bug 
that should call setOutputStream within doPrivileged.

I think it'd be simpler if SocketHandler no-arg constructor can first 
get the port and host from the logging properties so that it doesn't 
need to differentiate hostAndPortSet is set and ConfigureAction no-arg 
constructor can be removed.

Daniel/Peter - do we have tests to cover these permission check for 
these handlers?

Mandy

>
> This variant could be backported by simply replacing a limited variant 
> of doPrivileged (introduced in JDK 8) with full variant and still not 
> elevate the privilege of Socket creation in SocketHandler. I also 
> removed the need to subclass various ConfigureAction(s) with 
> annonymous inner subclasses by introducing overloaded constructors to 
> ConfigureActions(s) that follow the overloaded constructors of various 
> Handlers.
>
> Regards, Peter
>
> On 12/14/2013 12:25 PM, Peter Levart wrote:
>> Hi Mandy,
>>
>> On 12/13/2013 12:37 AM, Mandy Chung wrote:
>>> Hi Peter,
>>>
>>> On 12/8/2013 11:19 AM, Peter Levart wrote:
>>>> H Mandy,
>>>>
>>>> I created an issue for it nevertheless:
>>>>
>>>> https://bugs.openjdk.java.net/browse/JDK-8029781
>>>>
>>>> You're right, doPrivileged() is a more straight-forward approach 
>>>> than 'sealed' variable. Since this might only be considered for 
>>>> inclusion in JDK9 when lambdas are already a tried technology, how 
>>>> do you feel about using them for platform code like logging? As far 
>>>> as I know (just checked), lambda meta-factory is not using any 
>>>> j.u.logging, so there is no danger of initialization loops or similar:
>>>>
>>>> http://cr.openjdk.java.net/~plevart/jdk8-tl/jul.Handler.sealed/webrev.03/ 
>>>>
>>>
>>> Sorry for the delay to get to this.
>>
>> No rush. We have time before JDK9 gets set-up and running...
>>
>>>
>>> Alan is right that java.lang.invoke.ProxyClassesDumper does use 
>>> PlatformLogger which will forward calls to j.u.logging if 
>>> -Djava.util.logging.config.file is set or java.util.logging has been 
>>> initialized (via other j.u.logging call).  It means that it may lead 
>>> to recursive initialization.  Also the current PlatformLogger 
>>> implementation formats the message in the same way as j.u.logging 
>>> that may load locale providers and other classes.  I am afraid there 
>>> are issues to tease out and resolve.
>>
>> It's unfortunate that a lambda debugging feature prevents us from 
>> using a basic language feature in j.u.logging code. As far as I know, 
>> java.lang.invoke.ProxyClassesDumper is only used if 
>> 'jdk.internal.lambda.dumpProxyClasses' system property is set to 
>> point to a directory where lambda proxy class files are to be dumped 
>> as they are generated - a debugging hook therefore. Wouldn't it be 
>> good-enough if error messages about not-being able to set-up/use the 
>> dump facility were output to System.err directly - not using 
>> PlatformLogger at all?
>>
>>>
>>> The overloads the doPrivileged method makes it cumbersome to use 
>>> lambda that causes you to workaround it by adding a new 
>>> PrivilegedVoidAction interface which is clever.  So I think it isn't 
>>> too bad for this patch to use anonymous inner class and have the 
>>> doPrivileged call in the constructor.
>>
>> Right. I have prepared a modified webrev which doesn't use lambdas:
>>
>> http://cr.openjdk.java.net/~plevart/jdk8-tl/jul.Handler.sealed/webrev.04/
>>
>> In attempt to minimize the boilerplate, I haven't just replaced 
>> lambdas with anonymous inner classes, but rather turned all private 
>> configure() methods into ConfigureAction inner classes. In two 
>> occasions (SocketHandler and StreamHandler), they are extended with 
>> anonymous inner classes to append some actions. In SocketHandler I 
>> kept the mechanics of transporting the checked IOException out of 
>> PrivilegedAction by wrapping it with Unchecked IOException and later 
>> unwrapping and throwing it, rather than using 
>> PrivilegedExceptionAction which would further complicate exception 
>> handling, since it declares throwing a general j.l.Exception, but the 
>> SocketHandler constructor only declares throwing IOException...
>>
>> I think this could be backported to 7u as-is.
>>
>> Regards, Peter
>>
>>>
>>>
>>> Mandy
>>
>