Re: [PATCH v2] KEYS: trusted: allow module init if TPM is inactive or deactivated

[Roberto Sassu]

On 8/2/2019 5:34 PM, Roberto Sassu wrote:
> On 8/2/2019 5:30 PM, Tyler Hicks wrote:
> > On 2019-08-02 17:07:33, Roberto Sassu wrote:
> > > Commit c78719203fc6 ("KEYS: trusted: allow trusted.ko to initialize 
> > > w/o a
> > > TPM") allows the trusted module to be loaded even a TPM is not found to
> > ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ ^ if
> >
> > > avoid module dependency problems.
> > >
> > > However, trusted module initialization can still fail if the TPM is
> > > inactive or deactivated. This patch ignores tpm_get_random() errors in
> > > init_digests() and returns -EFAULT in pcrlock() if the TPM didn't return
> > > random data.
> > >
> > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> >
> > The code changes look correct to me.
> >
> > ÂÂ Reviewed-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxx>
> >
> > For whoever takes this patch through their tree, I think that adding the
> > following Fixes tag would be useful (as well as cc'ing stable):
> >
> > ÂÂ Fixes: 240730437deb ("KEYS: trusted: explicitly use tpm_chip 
> > structure...")
> >
> > I think it is also worth leaving a short note, in the commit message,
> > for backporters that commit 782779b60faa ("tpm: Actually fail on TPM
> > errors during "get random"") should be included with any backports of
> > this patch.
>
> Right, thanks. I wait for Jarkko's comments and I add both the Fixes tag
> and the short note in the next version of the patch.

Uhm, I was thinking that maybe it is not necessary to mention commit
782779b60faa. This patch would still return 0 even if that commit is not
backported (TPM_ERR_DISABLED < TPM_MAX_DIGEST_SIZE).

Roberto

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