Re: [PATCH 1/2] integrity: Add errno field in audit message

[Lakshmi Ramasubramanian]

On 6/16/20 8:29 AM, Steve Grubb wrote:

> > > > > The idea is a good idea, but you're assuming that "result" is always
> > > > > errno.  That was probably true originally, but isn't now.  For
> > > > > example, ima_appraise_measurement() calls xattr_verify(), which
> > > > > compares the security.ima hash with the calculated file hash.  On
> > > > > failure, it returns the result of memcmp().  Each and every code path
> > > > > will need to be checked.
> > > >
> > > > Good catch Mimi.
> > > >
> > > > Instead of "errno" should we just use "result" and log the value given
> > > > in the result parameter?
> > >
> > > That would likely collide with another field of the same name which is
> > > the
> > > operation's results. If it really is errno, the name is fine. It's
> > > generic
> > > enough that it can be reused on other events if that mattered.
> >
> > Steve, what is the historical reason why we have both "res" and
> > "result" for indicating a boolean success/fail?  I'm just curious how
> > we ended up this way, and who may still be using "result".
>
> I think its pam and some other user space things did this. But because of
> mixed machines in datacenters supporting multiple versions of OS, we have to
> leave result alone. It has to be 0,1 or success/fail. We cannot use it for
> errno.

As Mimi had pointed out, since the value passed in result parameter is 
not always an error code, "errno" is not an appropriate name.

Can we add a new field, say, "op_result" to report the result of the 
specified operation?

thanks,
 -lakshmi