[OpenJDK 2D-Dev] Crash in CGraphicsDevice.m

[Sergey Bylokhov]

Hi, Bill.

The similar bug was reported recently:
https://bugs.openjdk.java.net/browse/JDK-8211992

The root cause is how we use CoreGraphics display ID. This identifier can become non-valid at any time therefore methods, which is using this id should be ready to it.

And this bug found a few places which does not take care about the rule above.

I am working on the fix for jdk12.

On 10/10/2018 08:45, Bill York wrote:
> 2d-dev folks,
> 
> I work on a product called MATLAB and we have about 60 reports from customers on Mac related to a crash in CGraphicsDevice.m
> 
> Please let  me know if this is the right way to report a crash and discuss getting it resolved.
> 
> Here are the details:
> 
> CGraphicsDevice.m is a native file in support of Java drawing and gets called from Java_sun_awt_CGraphicsDevice_nativeGetDisplayMode
> 
> While I can’t reproduce the problem, it looks like the display pointer is becoming invalid for a time when the user’s laptop opens or closes.
> 
> Looking at this source code:
> 
> http://cr.openjdk.java.net/~serb/8000629/webrev.08/src/macosx/native/sun/awt/CGraphicsDevice.m.html
> 
> I see a direct call to CFStringCompare without a check for a NULL CFStringRef.
> 
>   * (CFStringCompare(mode, CFSTR(kIO30BitDirectPixels), kCFCompareCaseInsensitive) == kCFCompareEqualTo)
> 
> I believe if this code returned 0, the crash would not occur though there may be some other cleanup in the surrounding call frames.
> 
> Bill
> 


-- 
Best regards, Sergey.