[Makedumpfile PATCH 0/2] Fix refiltering when kaslr enabled

[Pratyush Anand]

Hi Atsushi,

On Friday 28 April 2017 12:22 PM, Atsushi Kumagai wrote:
> Hello Pratyush,
>
> Thanks for your report, I have received this.
> I'm on vacation until Mar 8, I'll review it when I return from vacation.

Any further comment on it?
Otherwise, I will send a v2 after accommodating concern from Xunlei.

~Pratyush


>
> Thanks,
> Atsushi Kumagai
>
>> Hi All,
>>
>> We came across another failure in makedumpfile when kaslr is enabled. This
>> failure occurs when we try re-filtering. We try to erase some symbol from a
>> dumpfile which was copied/compressed from /proc/vmcore using makedumpfile.
>>
>> We have very limited symbol information in vmcoreinfo. So symbols to be
>> erased may not be available in vmcoreinfo and we look for it in vmlinux.
>> However,  symbol address from vmlinux is a static address which differs
>>from run time address with KASLR_OFFSET. Therefore, reading any "virtual
>> address of vmlinux" from vmcore is not possible.
>>
>> These patches finds runtime  KASLR offset and then calculates run time
>> address of symbols read from vmlinux.
>>
>> Since, I am not an expert of x86, and these patches touch x86 part of
>> makedumpfile, therefore I have CCed x86 experts. Please, provide your
>> review comment and let me know if you think there could have been a better
>> way to resolve this issue.
>>
>> thanks
>>
>> ~Pratyush
>>
>> Pratyush Anand (2):
>>  makedumpfile: add runtime kaslr offset if it exists
>>  x86_64: calculate page_offset in case of re-filtering
>>
>> arch/x86_64.c  | 45 +++++++++++++++++++++++++++++++++++++++++++--
>> erase_info.c   |  1 +
>> makedumpfile.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
>> makedumpfile.h | 15 +++++++++++++++
>> 4 files changed, 103 insertions(+), 2 deletions(-)
>>
>> --
>> 2.9.3
>