On Mon, 19 Jul 2021 at 12:40, Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote: > > Hello Andreas, > > On 16.07.21 10:17, Andreas Rammhold wrote: > > Before this commit the kernel could end up with no trusted key sources > > even thought both of the currently supported backends (tpm & tee) were > > compoiled as modules. This manifested in the trusted key type not being > > registered at all. > > I assume (TPM) trusted key module use worked before the TEE rework? If so, > > an appropriate Fixes: Tag would then be in order. > > > When checking if a CONFIG_… preprocessor variable is defined we only > > test for the builtin (=y) case and not the module (=m) case. By using > > the IS_ENABLE(…) macro we to test for both cases. > > It looks to me like you could now provoke a link error if TEE is a module > and built-in trusted key core tries to link against trusted_key_tee_ops. > That's true. > One solution for that IS_REACHABLE(). Another is to address the root cause, > which is the inflexible trusted keys Kconfig description: > > - Trusted keys despite TEE support can still only be built when TCG_TPM is enabled > - There is no support to have TEE or TPM enabled without using those for > enabled trusted keys as well > - As you noticed, module build of the backend has issues > > I addressed these three issues in a patch[1], a month ago, but have yet to > receive feedback. That's an oversight on my part since this patch was part of the new CAAM trust source patch-set. Although I do admit that it was on my TODO list. So I have provided some feedback on that patch. Can you post the next version as an independent fix patch? -Sumit > > [1]: https://lore.kernel.org/linux-integrity/f8285eb0135ba30c9d846cf9dd395d1f5f8b1efc.1624364386.git-series.a.fatoum@xxxxxxxxxxxxxx/ > > Cheers, > Ahmad > > > Signed-off-by: Andreas Rammhold <andreas@xxxxxxxxxxx> > > --- > > security/keys/trusted-keys/trusted_core.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c > > index d5c891d8d353..fd640614b168 100644 > > --- a/security/keys/trusted-keys/trusted_core.c > > +++ b/security/keys/trusted-keys/trusted_core.c > > @@ -27,10 +27,10 @@ module_param_named(source, trusted_key_source, charp, 0); > > MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)"); > > > > static const struct trusted_key_source trusted_key_sources[] = { > > -#if defined(CONFIG_TCG_TPM) > > +#if IS_ENABLED(CONFIG_TCG_TPM) > > { "tpm", &trusted_key_tpm_ops }, > > #endif > > -#if defined(CONFIG_TEE) > > +#if IS_ENABLED(CONFIG_TEE) > > { "tee", &trusted_key_tee_ops }, > > #endif > > }; > > > > > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
