Crash problem in net.dll

[Michael McMahon]

Just to be clear, I will run the tests on the fix and push the change
assuming everything is ok. There is a webrev here
http://cr.openjdk.java.net/~michaelm/7084560/webrev.1/

Thanks,
Michael.

On 29/08/11 15:33, Michael McMahon wrote:
> Jonathan,
>
> Bug id 7084560 has been created to track this. That fix looks fine
> to me.
>
> Thanks,
> Michael.
>
> On 29/08/11 10:20, Jonathan Lu wrote:
>> Hi Michael,
>>
>> Thanks for reminding, I checked the source under src/windows folder 
>> and found two more places to change.
>>
>> Here's the updated patch:
>>
>> diff -r 9b8c96f96a0f src/windows/native/java/net/NetworkInterface.c
>> --- a/src/windows/native/java/net/NetworkInterface.c    Mon Jun 27 
>> 13:21:34 2011 -0700
>> +++ b/src/windows/native/java/net/NetworkInterface.c    Mon Aug 29 
>> 17:02:56 2011 +0800
>> @@ -504,8 +504,7 @@
>>       */
>>      if (netaddrCount < 0) {
>>          netaddrCount = enumAddresses_win(env, ifs, &netaddrP);
>> -        if ((*env)->ExceptionOccurred(env)) {
>> -            free_netaddr(netaddrP);
>> +        if (netaddrCount == -1) {
>>              return NULL;
>>          }
>>      }
>> diff -r 9b8c96f96a0f 
>> src/windows/native/java/net/NetworkInterface_winXP.c
>> --- a/src/windows/native/java/net/NetworkInterface_winXP.c    Mon Jun 
>> 27 13:21:34 2011 -0700
>> +++ b/src/windows/native/java/net/NetworkInterface_winXP.c    Mon Aug 
>> 29 17:02:56 2011 +0800
>> @@ -194,8 +194,7 @@
>>      while (curr != NULL) {
>>          netaddr *netaddrP;
>>          ret = enumAddresses_win(env, curr, &netaddrP);
>> -        if ((*env)->ExceptionOccurred(env)) {
>> -            free_netaddr(netaddrP);
>> +        if (ret == -1) {
>>              return -1;
>>          }
>>          curr->addrs = netaddrP;
>> @@ -449,8 +448,7 @@
>>       */
>>      if (netaddrCount < 0) {
>>          netaddrCount = enumAddresses_win(env, ifs, &netaddrP);
>> -        if ((*env)->ExceptionOccurred(env)) {
>> -            free_netaddr(netaddrP);
>> +        if (count == -1) {
>>              return NULL;
>>          }
>>      }
>>
>> And from my point of view, such scenario may also appear in other 
>> parts, maybe a more thorough check is needed for all modules.
>>
>> Regards!
>> - Jonathan Lu
>>
>> On 08/29/2011 04:40 PM, Michael McMahon wrote:
>>> Jonathan,
>>>
>>> I think the change looks reasonable. But, we should make the equivalent
>>> change at the other site where enumAddresses_win() is called in the 
>>> same file.
>>>
>>> - Michael.
>>>
>>> On 29/08/11 09:14, Jonathan Lu wrote:
>>>> Hello everybody,
>>>>
>>>> I got one crash issue on OpenJDK7 windows build.
>>>>
>>>> I captured the stack trace of such a crash, which happens 
>>>> intermittently on my 64bit Windows 2008 server. But unfortunately I 
>>>> have no simple test case to reproduce this problem.
>>>>
>>>> RtlInterlockedFlushSList+0x2ea (0x779F2A7F [ntdll+0x32a7f])
>>>> RtlInterlockedFlushSList+0x572 (0x779F2D07 [ntdll+0x32d07])
>>>> RtlInterlockedFlushSList+0x45d (0x779F2BF2 [ntdll+0x32bf2])
>>>> HeapFree+0x14 (0x755A14D1 [kernel32+0x114d1])
>>>> free+0x1c (0x7284016A [msvcr100+0x1016a])
>>>> free_netaddr+0x11 (networkinterface.c:107, 0x725A12AC [net+0x12ac])
>>>> getAllInterfacesAndAddresses+0xb6 (networkinterface_winxp.c:199, 
>>>> 0x725AB4C8 [net+0xb4c8])
>>>> Java_java_net_NetworkInterface_getAll_XP+0x12 
>>>> (networkinterface_winxp.c:693, 0x725AB7AB [net+0xb7ab])
>>>>
>>>> From the code at 
>>>> src/windows/native/java/net/NetworkInterface_winXP.c:195, I believe 
>>>> it is the dangling pointers that caused this problem. The 
>>>> uninitialized pointer netaddrP is exceptionally freed if the call 
>>>> to Windows API "GetIpAddrTable()" fails.
>>>>
>>>> So here's one proposed solution for this issue, can anybody please 
>>>> help to take a look?
>>>>
>>>> diff -r 9b8c96f96a0f 
>>>> src/windows/native/java/net/NetworkInterface_winXP.c
>>>> --- a/src/windows/native/java/net/NetworkInterface_winXP.c    Mon 
>>>> Jun 27 13:21:34 2011 -0700
>>>> +++ b/src/windows/native/java/net/NetworkInterface_winXP.c    Mon 
>>>> Aug 29 14:59:09 2011 +0800
>>>> @@ -194,8 +194,7 @@
>>>>      while (curr != NULL) {
>>>>          netaddr *netaddrP;
>>>>          ret = enumAddresses_win(env, curr, &netaddrP);
>>>> -        if ((*env)->ExceptionOccurred(env)) {
>>>> -            free_netaddr(netaddrP);
>>>> +        if (ret == -1) {
>>>>              return -1;
>>>>          }
>>>>          curr->addrs = netaddrP;
>>>>
>>>> Best regards!
>>>>
>>>>                                                                                                                                
>>>> Jonathan Lu
>>>>
>>>
>>
>