Crash problem in net.dll

[Michael McMahon]

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
>