Re: [RFC][PATCH] selinux: Report result in avc messages
I could make it permissive=0 or permissive=1 if that is less
confusing. It doesn't necessarily correspond to the result of the
system call, just the avc_has_perm call, as e.g. the kernel checks
CAP_DAC_OVERRIDE and falls back to CAP_DAC_READ_SEARCH if only
read/search access was requested, and there are other cases where a
permission denial has a side effect rather than preventing the system
call (e.g. CAP_FSETID).
On Wed, Apr 30, 2014 at 6:34 AM, Daniel J Walsh <dwalsh(a)redhat.com> wrote:
On 04/30/2014 09:29 AM, Steve Grubb wrote:
> On Wednesday, April 30, 2014 08:59:50 AM Daniel J Walsh wrote:
>> How about permitted rather then allowed.
> I think permitted is already in an AVC.
Not sure where.
>
>> On 04/29/2014 10:59 PM, Eric Paris wrote:
>>> On Tue, 2014-04-29 at 16:54 -0700, Stephen Smalley wrote:
>>>> Requested for Android in order to distinguish denials that are not in
>>>> fact breaking anything yet due to permissive domains versus denials
>>>> that are being enforced, but seems generally useful. result field was
>>>> already in the selinux audit data structure and was being passed to
>>>> avc_audit() but wasn't being used. Seems to cause no harm to
ausearch
>>>> or audit2allow to add it as a field. Comments?
>>> I think it's a great idea, but I'm worried that Steve is going to
get
>>> grumpy because an AVC record is going to have a result= field which is
>>> similar, but not necessarily related to the res= field of a SYSCALL
>>> record.
> I think that I'll have to parse this field no matter what. Its probably that
> important. In the syscall, we use success= to be the final determination.
>
>
>>> Seems easily confused (although probably 9999 times out of
>>> 10000 they will be the same)
> Why would this ever not be correct? Are there times when we get an AVC with a
> denial _and_ the syscall completes successfully?
>
> I'd suggest using res= since its in the audit dictionary and means exactly
> what you are wanting to use it for. In it, 1 is success, 0 is failure.
>
I have seen AVC's where the success=yes in enforcing mode. Basically
the kernel takes a different code path and the syscall succeeds. Most
of these end up as dontaudits.
>>> So while I wholeheartedly think we should take the idea, I wonder if
>>> someone can dream up a name that isn't confusingly similar...
>>>
>>> I can't think of anything...
> There is thesaurus.com. :-)
>
> consequence, outcome, effect, reaction, conclusion, verdict, decision,
> judgement, finding, ruling, answer, solution, recommendation, order, ...
>
> -Steve