From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: Andreas Rammhold <andreas@rammhold.de>,
James Bottomley <jejb@linux.ibm.com>,
Jarkko Sakkinen <jarkko@kernel.org>,
Mimi Zohar <zohar@linux.ibm.com>,
David Howells <dhowells@redhat.com>,
James Morris <jmorris@namei.org>,
"Serge E . Hallyn" <serge@hallyn.com>,
linux-integrity@vger.kernel.org, keyrings@vger.kernel.org,
linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org,
Pengutronix Kernel Team <kernel@pengutronix.de>
Subject: Re: [PATCH] KEYS: trusted: Fix trusted key backends when building as module
Date: Mon, 19 Jul 2021 09:10:01 +0200 [thread overview]
Message-ID: <0a684d56-66d0-184e-4853-9faafa2d243d@pengutronix.de> (raw)
In-Reply-To: <20210716081722.4130161-1-andreas@rammhold.de>
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.
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.
[1]: https://lore.kernel.org/linux-integrity/f8285eb0135ba30c9d846cf9dd395d1f5f8b1efc.1624364386.git-series.a.fatoum@pengutronix.de/
Cheers,
Ahmad
> Signed-off-by: Andreas Rammhold <andreas@rammhold.de>
> ---
> 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 |
next prev parent reply other threads:[~2021-07-19 7:10 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-16 8:17 [PATCH] KEYS: trusted: Fix trusted key backends when building as module Andreas Rammhold
2021-07-19 6:26 ` Sumit Garg
2021-07-19 7:10 ` Ahmad Fatoum [this message]
2021-07-19 8:06 ` Sumit Garg
2021-07-19 9:13 ` andreas
2021-07-27 2:57 ` Jarkko Sakkinen
2021-07-27 2:55 ` Jarkko Sakkinen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0a684d56-66d0-184e-4853-9faafa2d243d@pengutronix.de \
--to=a.fatoum@pengutronix.de \
--cc=andreas@rammhold.de \
--cc=dhowells@redhat.com \
--cc=jarkko@kernel.org \
--cc=jejb@linux.ibm.com \
--cc=jmorris@namei.org \
--cc=kernel@pengutronix.de \
--cc=keyrings@vger.kernel.org \
--cc=linux-integrity@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=serge@hallyn.com \
--cc=zohar@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).