Re: [PATCH V2] audit: log 32-bit socketcalls

[Richard Guy Briggs]

On 2017-01-13 10:18, Eric Paris wrote:
> On Fri, 2017-01-13 at 10:06 -0500, Richard Guy Briggs wrote:
> > On 2017-01-13 09:42, Eric Paris wrote:
> > > On Fri, 2017-01-13 at 04:51 -0500, Richard Guy Briggs wrote:
> 
> 
> > > > diff --git a/include/linux/audit.h b/include/linux/audit.h
> > > > index 9d4443f..43d8003 100644
> > > > --- a/include/linux/audit.h
> > > > +++ b/include/linux/audit.h
> > > > @@ -387,6 +387,18 @@ static inline int audit_socketcall(int
> > > > nargs,
> > > > unsigned long *args)
> > > >  		return __audit_socketcall(nargs, args);
> > > >  	return 0;
> > > >  }
> > > > +static inline int audit_socketcall_compat(int nargs, u32 *args)
> > > > +{
> > > > +	if (unlikely(!audit_dummy_context())) {
> > > 
> > > I've always hated these likely/unlikely. Mostly because I think
> > > they
> > > are so often wrong. I believe this says that you compiled audit in
> > > but
> > > you expect it to be explicitly disabled. While that is (recently)
> > > true
> > > in Fedora I highly doubt that's true on the vast majority of
> > > systems
> > > that have audit compiled in.
> > 
> > It has been argued that audit should have pretty much no performance
> > impact if it is not in use and that if it is, we're willing to take
> > the
> > more significant overhead of the rest of the code for the sake of one
> > test to determine whether or not to follow this code path.
> 
> Ok, I can buy that argument. Not sure its where I would have settled,
> but it does make sense. I'll obviously defer to Paul on what he wants
> out of style. I always assume the compiler is brilliant and write
> stupid code but your logic is sound there too.
> 
> You can/should pretend I said nothing.

You're keeping me honest and making me work for my dinner!  ;-)

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Kernel Security Engineering, Base Operating Systems, Red Hat
Remote, Ottawa, Canada
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