Re: [PATCH 2/3] integrity: Move import of MokListRT certs to a separate routine

[Lenny Szubowicz]

On 9/2/20 3:55 AM, Andy Shevchenko wrote:
> On Wed, Aug 26, 2020 at 6:45 AM Lenny Szubowicz <lszubowi@xxxxxxxxxx> wrote:
> > Move the loading of certs from the UEFI MokListRT into a separate
> > routine to facilitate additional MokList functionality.
> >
> > There is no visible functional change as a result of this patch.
> > Although the UEFI dbx certs are now loaded before the MokList certs,
> > they are loaded onto different key rings. So the order of the keys
> > on their respective key rings is the same.
>
> ...
>
> >   /*
> > + * load_moklist_certs() - Load MokList certs
> > + *
> > + * Returns:    Summary error status
> > + *
> > + * Load the certs contained in the UEFI MokListRT database into the
> > + * platform trusted keyring.
> > + */
>
> Hmm... Is it intentionally kept out of kernel doc format?

Yes. Since this is a static local routine, I thought that it
shouldn't be included by kerneldoc. But I wanted to generally adhere
to the kernel doc conventions for a routine header. To that end,
in V2 I move the "Return:" section to come after the short description.

> > +static int __init load_moklist_certs(void)
> > +{
> > +       efi_guid_t mok_var = EFI_SHIM_LOCK_GUID;
> > +       void *mok = NULL;
> > +       unsigned long moksize = 0;
> > +       efi_status_t status;
> > +       int rc = 0;
>
> Redundant assignment (see below).
>
> > +       /* Get MokListRT. It might not exist, so it isn't an error
> > +        * if we can't get it.
> > +        */
> > +       mok = get_cert_list(L"MokListRT", &mok_var, &moksize, &status);
>
> > +       if (!mok) {
>
> Why not positive conditional? Sometimes ! is hard to notice.
>
> > +               if (status == EFI_NOT_FOUND)
> > +                       pr_debug("MokListRT variable wasn't found\n");
> > +               else
> > +                       pr_info("Couldn't get UEFI MokListRT\n");
> > +       } else {
> > +               rc = parse_efi_signature_list("UEFI:MokListRT",
> > +                                             mok, moksize, get_handler_for_db);
> > +               if (rc)
> > +                       pr_err("Couldn't parse MokListRT signatures: %d\n", rc);
> > +               kfree(mok);
>
>   kfree(...)
>   if (rc)
>    ...
>   return rc;
>
> And with positive conditional there will be no need to have redundant
> 'else' followed by additional level of indentation.
>
> > +       }
>
> > +       return rc;
>
> return 0;
>
> > +}
>
> P.S. Yes, I see that the above was in the original code, so, consider
> my comments as suggestions to improve the code.

I agree that your suggestions improve the code. I've incorporated this
into V2.

                       -Lenny.