Re: [PATCH 2/2] keys, trusted: seal with a policy

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

On Fri, Nov 20, 2015 at 01:34:35PM +1100, James Morris wrote:
> On Wed, 18 Nov 2015, Jarkko Sakkinen wrote:
> 
> > On Wed, Nov 18, 2015 at 11:21:01AM +1100, James Morris wrote:
> > > On Tue, 17 Nov 2015, Jarkko Sakkinen wrote:
> > > 
> > > >  			}
> > > >  			break;
> > > > +		case Opt_policydigest:
> > > > +			if (!tpm2 ||
> > > > +			    strlen(args[0].from) != (2 * opt->digest_len))
> > > > +				return -EINVAL;
> > > > +			kfree(opt->policydigest);
> > > > +			opt->policydigest = kzalloc(opt->digest_len,
> > > > +						    GFP_KERNEL);
> > > 
> > > Is it correct to kfree opt->policydigest here before allocating it?
> > 
> > I think so. The same option might be encountered multiple times.
> 
> This would surely signify an error?

I'm following the semantics of other options. That's why I implemented
it that way for example:

keyctl add trusted kmk "new 32 keyhandle=0x80000000 keyhandle=0x80000000"

is perfectly OK. I just thought that it'd be more odd if this option
behaved in a different way...

> -- 
> James Morris
> <jmorris@namei.org>

/Jarkko