[8u] RFR: JDK-8147451: Crash in Method::checked_resolve_jmethod_id(_jmethodID*)

[Shafi Ahmad]

Hi,

 

Thanks Serguei for looking into it.

 

Please find the updated webrev with suggested code change.

Updated webrev link: http://cr.openjdk.java.net/~shshahma/8147451/webrev.01/

 

Regards,

Shafi

 

From: Serguei Spitsyn 
Sent: Wednesday, June 08, 2016 11:40 AM
To: hotspot-runtime-dev at openjdk.java.net; Shafi Ahmad
Cc: Coleen Phillimore
Subject: Re: [8u] RFR: JDK-8147451: Crash in Method::checked_resolve_jmethod_id(_jmethodID*)

 

Once again with Shafi's email address added ...

Hi Shafi,

You did not reply on my email above.
It can be because your email address was not directly included into the list.

Thanks,
Serguei


On 6/3/16 17:32, HYPERLINK "mailto:serguei.spitsyn at oracle.com"serguei.spitsyn at oracle.com wrote:

Hi Shafi,

I agree that this change is safe.
However, there are still two more spots that need to be fixed in the jdk8:

   // During class unloading the methods are cleared, which is different
   // than freed.
   void clear_all_methods() {
     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
       for (int i = 0; i< number_of_methods; i++) {
-      _methods[i] = NULL;
+      b->_methods[i] = NULL;
       }
     }
   }
@@ -1799,7 +1811,7 @@
     int count = 0;
     for (JNIMethodBlock* b = this; b != NULL; b = b->_next) {
       for (int i = 0; i< number_of_methods; i++) {
-        if (_methods[i] != _free_method) count++;
+        if (b->_methods[i] != _free_method) count++;
       }
     }
     return count;
@@ -1871,6 +1883,10 @@
   return o;
 };


You can find this information in one of the bug report comments.

Thanks,
Serguei



On 6/3/16 15:18, Coleen Phillimore wrote: 

This seems like a safe change. Coleen On 5/24/16 4:34 AM, Shafi Ahmad wrote: 

Hi,   Please review the small code change for bug: "JDK-8147451: Crash in Method::checked_resolve_jmethod_id(_jmethodID*)" on jdk8u-dev   Summary: resolve_jmethod_id() is getting called with invalid jmethodID and there is no check for validity of the method id inside this function. So before calling resolve_jmethod_id() we should check its validity. This code change add this check. Also inside Method::is_method_id() we are not checking return value of method_holder(). It may return NULL if method id is not valid so I have added null check for this too.   Webrev: HYPERLINK "http://cr.openjdk.java.net/%7Eshshahma/8147451/webrev.00/"http://cr.openjdk.java.net/~shshahma/8147451/webrev.00/ Jdk8 bug: https://bugs.openjdk.java.net/browse/JDK-8147451   Test:  Run jprt   Regards, Shafi