Message-ID: <61f5d74f861ce1015831649d3bca9272a2e3b7bf.camel@linux.ibm.com>
Subject: Re: [PATCH v8 09/17] KEYS: Rename
 get_builtin_and_secondary_restriction
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Jarkko Sakkinen <jarkko@kernel.org>,
        Eric Snowberg <eric.snowberg@oracle.com>
Cc:     "keyrings@vger.kernel.org" <keyrings@vger.kernel.org>,
        "linux-integrity@vger.kernel.org" <linux-integrity@vger.kernel.org>,
        "dhowells@redhat.com" <dhowells@redhat.com>,
        "dwmw2@infradead.org" <dwmw2@infradead.org>,
        "herbert@gondor.apana.org.au" <herbert@gondor.apana.org.au>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "jmorris@namei.org" <jmorris@namei.org>,
        "serge@hallyn.com" <serge@hallyn.com>,
        "keescook@chromium.org" <keescook@chromium.org>,
        "torvalds@linux-foundation.org" <torvalds@linux-foundation.org>,
        "weiyongjun1@huawei.com" <weiyongjun1@huawei.com>,
        "nayna@linux.ibm.com" <nayna@linux.ibm.com>,
        "ebiggers@google.com" <ebiggers@google.com>,
        "ardb@kernel.org" <ardb@kernel.org>,
        "nramas@linux.microsoft.com" <nramas@linux.microsoft.com>,
        "lszubowi@redhat.com" <lszubowi@redhat.com>,
        "jason@zx2c4.com" <jason@zx2c4.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>,
        "linux-security-module@vger.kernel.org" 
        <linux-security-module@vger.kernel.org>,
        "James.Bottomley@hansenpartnership.com" 
        <James.Bottomley@hansenpartnership.com>,
        "pjones@redhat.com" <pjones@redhat.com>,
        Konrad Wilk <konrad.wilk@oracle.com>
Date:   Wed, 01 Dec 2021 08:46:53 -0500
In-Reply-To: <YadOLrHb14MEfphi@iki.fi>
References: <20211124044124.998170-1-eric.snowberg@oracle.com>
         <20211124044124.998170-10-eric.snowberg@oracle.com>
         <fb1d583f588e3f46fdadbe3cf6288bb098ff45f8.camel@kernel.org>
         <8906F8A4-313F-45E5-8ABD-A1A2D07BFD93@oracle.com> <YadOLrHb14MEfphi@iki.fi>
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On Wed, 2021-12-01 at 12:27 +0200, Jarkko Sakkinen wrote:
> On Tue, Nov 30, 2021 at 05:21:45PM +0000, Eric Snowberg wrote:
> > 
> > 
> > > On Nov 26, 2021, at 5:49 PM, Jarkko Sakkinen <jarkko@kernel.org> wrote:
> > > 
> > > On Tue, 2021-11-23 at 23:41 -0500, Eric Snowberg wrote:
> > >> In preparation for returning either the existing
> > >> restrict_link_by_builtin_and_secondary_trusted or the upcoming
> > >> restriction that includes the trusted builtin, secondary and
> > >> machine keys, to improve clarity, rename
> > >> get_builtin_and_secondary_restriction to get_secondary_restriction.
> > >> 
> > >> Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
> > >> Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
> > >> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
> > >> ---
> > >> v6: Initial version
> > >> v7: Unmodified from v7
> > >> v8: Code unmodified from v7, added Mimi's Reviewed-by
> > >> ---
> > >>  certs/system_keyring.c | 4 ++--
> > >>  1 file changed, 2 insertions(+), 2 deletions(-)
> > >> 
> > >> diff --git a/certs/system_keyring.c b/certs/system_keyring.c
> > >> index 692365dee2bd..8f1f87579819 100644
> > >> --- a/certs/system_keyring.c
> > >> +++ b/certs/system_keyring.c
> > >> @@ -77,7 +77,7 @@ int restrict_link_by_builtin_and_secondary_trusted(
> > >>   * Allocate a struct key_restriction for the "builtin and secondary trust"
> > >>   * keyring. Only for use in system_trusted_keyring_init().
> > >>   */
> > >> -static __init struct key_restriction *get_builtin_and_secondary_restriction(void)
> > >> +static __init struct key_restriction *get_secondary_restriction(void)
> > >>  {
> > >>         struct key_restriction *restriction;
> > >>  
> > >> @@ -117,7 +117,7 @@ static __init int system_trusted_keyring_init(void)
> > >>                                KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH |
> > >>                                KEY_USR_WRITE),
> > >>                               KEY_ALLOC_NOT_IN_QUOTA,
> > >> -                             get_builtin_and_secondary_restriction(),
> > >> +                             get_secondary_restriction(),
> > >>                               NULL);
> > >>         if (IS_ERR(secondary_trusted_keys))
> > >>                 panic("Can't allocate secondary trusted keyring\n");
> > > 
> > > This is wrong order.
> > > 
> > > You should first do the changes that make the old name
> > > obsolete and only after that have a patch that does the
> > > rename. Unfortunately, this patch cannot possibly acked
> > > with the current order.
> >
> > I can change the order, but I'm confused how this would work for a git bisect. 
> > If the rename happens afterwards, now two patches will always need to be 
> > reverted instead of the possibility of one.  Is this your expectation?

If the keyring name change is independent of any other changes, as
Jarkko suggested, nothing would break.

> I'd drop this patch altogether. Old name is a bit ugly but does it matter
> all that much?

The name "get_builtin_and_secondary_restriction" implies trust based on
keys in the ".builtin_trusted_keys" and ".secondary_trusted_keys"
keyrings.  This patch set is extending that to include keys on the new
".machine" keyring, by linking it to the secondary keyring.  Is leaving
the name unchanged really an option?

> 
> You already 16 patches without this.

Agreed, it's a lot.  In the past, I've asked Eric to see if some of
them could be squashed.

Mimi