Re: [PATCH v2 0/6] KEXEC_SIG with appended signature

From: Philipp Rudo <prudo@redhat.com>
To: Michal Suchanek <msuchanek@suse.de>
Cc: keyrings@vger.kernel.org, kexec@lists.infradead.org,
	Mimi Zohar <zohar@linux.ibm.com>,
	Nayna <nayna@linux.vnet.ibm.com>, Rob Herring <robh@kernel.org>,
	linux-s390@vger.kernel.org, Vasily Gorbik <gor@linux.ibm.com>,
	Lakshmi Ramasubramanian <nramas@linux.microsoft.com>,
	Heiko Carstens <hca@linux.ibm.com>, Jessica Yu <jeyu@kernel.org>,
	linux-kernel@vger.kernel.org, David Howells <dhowells@redhat.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Luis Chamberlain <mcgrof@kernel.org>,
	Paul Mackerras <paulus@samba.org>,
	Hari Bathini <hbathini@linux.ibm.com>,
	Alexander Gordeev <agordeev@linux.ibm.com>,
	linuxppc-dev@lists.ozlabs.org,
	Frank van der Linden <fllinden@amazon.com>,
	Thiago Jung Bauermann <bauerman@linux.ibm.com>,
	Daniel Axtens <dja@axtens.net>,
	buendgen@de.ibm.com, Michael Ellerman <mpe@ellerman.id.au>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Christian Borntraeger <borntraeger@linux.ibm.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>,
	Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
	James Morris <jmorris@namei.org>,
	"Serge E. Hallyn" <serge@hallyn.com>,
	Sven Schnelle <svens@linux.ibm.com>, Baoquan He <bhe@redhat.com>,
	linux-crypto@vger.kernel.org, linux-integrity@vger.kernel.org,
	linux-security-module@vger.kernel.org
Subject: Re: [PATCH v2 0/6] KEXEC_SIG with appended signature
Date: Tue, 7 Dec 2021 17:10:14 +0100	[thread overview]
Message-ID: <20211207171014.2cfc4a54@rhtmp> (raw)
In-Reply-To: <cover.1637862358.git.msuchanek@suse.de>

Hi Michal,

i finally had the time to take a closer look at the series. Except for
the nit in patch 4 and my personal preference in patch 6 the code looks
good to me.

What I don't like are the commit messages on the first commits. In my
opinion they are so short that they are almost useless. For example in
patch 2 there is absolutely no explanation why you can simply copy the
s390 over to ppc. Or in patch 3 you are silently changing the error
code in kexec from EKEYREJECT to ENODATA. So I would appreciate it if
you could improve them a little.

Thanks
Philipp

On Thu, 25 Nov 2021 19:02:38 +0100
Michal Suchanek <msuchanek@suse.de> wrote:

> Hello,
> 
> This is resend of the KEXEC_SIG patchset.
> 
> The first patch is new because it'a a cleanup that does not require any
> change to the module verification code.
> 
> The second patch is the only one that is intended to change any
> functionality.
> 
> The rest only deduplicates code but I did not receive any review on that
> part so I don't know if it's desirable as implemented.
> 
> The first two patches can be applied separately without the rest.
> 
> Thanks
> 
> Michal
> 
> Michal Suchanek (6):
>   s390/kexec_file: Don't opencode appended signature check.
>   powerpc/kexec_file: Add KEXEC_SIG support.
>   kexec_file: Don't opencode appended signature verification.
>   module: strip the signature marker in the verification function.
>   module: Use key_being_used_for for log messages in
>     verify_appended_signature
>   module: Move duplicate mod_check_sig users code to mod_parse_sig
> 
>  arch/powerpc/Kconfig                     | 11 +++++
>  arch/powerpc/kexec/elf_64.c              | 14 ++++++
>  arch/s390/kernel/machine_kexec_file.c    | 42 ++----------------
>  crypto/asymmetric_keys/asymmetric_type.c |  1 +
>  include/linux/module_signature.h         |  1 +
>  include/linux/verification.h             |  4 ++
>  kernel/module-internal.h                 |  2 -
>  kernel/module.c                          | 12 +++--
>  kernel/module_signature.c                | 56 +++++++++++++++++++++++-
>  kernel/module_signing.c                  | 33 +++++++-------
>  security/integrity/ima/ima_modsig.c      | 22 ++--------
>  11 files changed, 113 insertions(+), 85 deletions(-)
> 