retrieve EIP/RIP for syscall in audit

retrieve EIP/RIP for syscall in audit

[Xiaokui Shu]

Hello,

I have a question about one of the features of audit.
Can I use audit to log the EIP/RIP at time of syscall? There is a "-i"
flag in strace that does the work.

When I compare the mechanisms of audit and strace(ptrace), I find
maybe it is not possible for strace to do so. Audit is on the kernel
side of a syscall, and does not know the audited program's internal
information (I am not sure if I understand it right). However, one can
still fetch extra information out of the syscall event (e.g. block a
syscall when coming, check the audited program stack and clear
blocking), but it may bring much overhead.

Best,
Xiaokui

Re: retrieve EIP/RIP for syscall in audit

[Xiaokui Shu]

On Thu, Jul 12, 2012 at 3:04 PM, Xiaokui Shu <subbyte@gmail.com> wrote:
> Hello,
>
> I have a question about one of the features of audit.
> Can I use audit to log the EIP/RIP at time of syscall? There is a "-i"
> flag in strace that does the work.
>
> When I compare the mechanisms of audit and strace(ptrace), I find
> maybe it is not possible for strace to do so. Audit is on the kernel
"strace" -> "audit" in the sentence above.
Sorry for the mistyping.

> side of a syscall, and does not know the audited program's internal
> information (I am not sure if I understand it right). However, one can
> still fetch extra information out of the syscall event (e.g. block a
> syscall when coming, check the audited program stack and clear
> blocking), but it may bring much overhead.
>
> Best,
> Xiaokui

Re: retrieve EIP/RIP for syscall in audit

[Steve Grubb]

On Thursday, July 12, 2012 03:04:11 PM Xiaokui Shu wrote:
> Hello,
> 
> I have a question about one of the features of audit.
> Can I use audit to log the EIP/RIP at time of syscall? There is a "-i"
> flag in strace that does the work.

No. The audit system does not collect that information. Maybe trace points or 
systemtap would be a better approach for that kind of thing?

-Steve

> When I compare the mechanisms of audit and strace(ptrace), I find
> maybe it is not possible for strace to do so. Audit is on the kernel
> side of a syscall, and does not know the audited program's internal
> information (I am not sure if I understand it right). However, one can
> still fetch extra information out of the syscall event (e.g. block a
> syscall when coming, check the audited program stack and clear
> blocking), but it may bring much overhead.
> 
> Best,
> Xiaokui
> 
> --
> Linux-audit mailing list
> Linux-audit@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-audit

Re: retrieve EIP/RIP for syscall in audit

[Xiaokui Shu]

Thank you very much! I will check systemtap for the feature.

Best,
Xiaokui

On Fri, Jul 13, 2012 at 1:27 PM, Steve Grubb <sgrubb@redhat.com> wrote:
> On Thursday, July 12, 2012 03:04:11 PM Xiaokui Shu wrote:
>> Hello,
>>
>> I have a question about one of the features of audit.
>> Can I use audit to log the EIP/RIP at time of syscall? There is a "-i"
>> flag in strace that does the work.
>
> No. The audit system does not collect that information. Maybe trace points or
> systemtap would be a better approach for that kind of thing?
>
> -Steve
>
>> When I compare the mechanisms of audit and strace(ptrace), I find
>> maybe it is not possible for strace to do so. Audit is on the kernel
>> side of a syscall, and does not know the audited program's internal
>> information (I am not sure if I understand it right). However, one can
>> still fetch extra information out of the syscall event (e.g. block a
>> syscall when coming, check the audited program stack and clear
>> blocking), but it may bring much overhead.
>>
>> Best,
>> Xiaokui
>>
>> --
>> Linux-audit mailing list
>> Linux-audit@redhat.com
>> https://www.redhat.com/mailman/listinfo/linux-audit