RFR: 8240956: SEGV in DwarfParser::process_dwarf after JDK-8234624

[David Holmes]

Correction ...

On 16/03/2020 12:53 pm, David Holmes wrote:
> On 16/03/2020 12:17 pm, David Holmes wrote:
>> Hi Yasumasa,
>>
>> I can't review this as I know nothing about the code, but I'm putting 
>> the patch through our internal testing.
> 
> Sorry but the crashes still exist:
> 
> #
> # A fatal error has been detected by the Java Runtime Environment:
> #
> #  SIGSEGV (0xb) at pc=0x00007fcdd403894e, pid=16948, tid=16949
> #
> # JRE version: Java(TM) SE Runtime Environment (15.0) (fastdebug build 
> 15-internal+0-2020-03-16-0214474.david.holmes.jdk-dev)
> # Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 
> 15-internal+0-2020-03-16-0214474.david.holmes.jdk-dev, mixed mode, 
> sharing, tiered, compressed oops, g1 gc, linux-amd64)
> # Problematic frame:
> # C  [libsaproc.so+0x494e]  DwarfParser::process_dwarf(unsigned long)+0x4e
> 
> in fact they seem worse as the test seems to always crash now.

Not worse - sorry. I see 6 failures out of 119 runs of the test in 
linux-x64. I don't see a pattern as to where it fails versus passes.

It doesn't fail for me locally.

David

> David
> 
>> David
>>
>> On 14/03/2020 11:35 am, Yasumasa Suenaga wrote:
>>> Hi all,
>>>
>>> Please review this change:
>>>
>>>    JBS: https://bugs.openjdk.java.net/browse/JDK-8240956
>>>    webrev: http://cr.openjdk.java.net/~ysuenaga/JDK-8240956/webrev.00/
>>>
>>> JDK-8234624 introduced DWARF parser in SA for unwinding native frames 
>>> in jstack mixed mode.
>>> However some error has seen intermittently after that.
>>>
>>> I investigated the cause of this, I found two concerns:
>>>
>>>    A: lack of buffer (.eh_frame section data) range check
>>>    B: Language personality routine and Language Specific Data Area 
>>> (LSDA) are not considered
>>>
>>> I addd range check for .eh_frame processing, and ignore personality 
>>> routine and LSDA in this webrev.
>>> Also I added bailout code if DWARF processing is failed due to these 
>>> concerns.
>>>
>>> This change has passed all tests on submit repo 
>>> (mach5-one-ysuenaga-JDK-8240956-20200313-1518-9434671),
>>> also I tested it on my Fedora 31 box and Oracle Linux 7.7 container.
>>>
>>>
>>> Thanks,
>>>
>>> Yasumasa