Re: [PATCH v5 0/6] KEXEC_SIG with appended signature

From: Michael Ellerman <mpe@ellerman.id.au>
To: Luis Chamberlain <mcgrof@kernel.org>,
	Michal Suchanek <msuchanek@suse.de>,
	David Howells <dhowells@redhat.com>,
	Aaron Tomlin <atomlin@redhat.com>
Cc: Nayna <nayna@linux.vnet.ibm.com>,
	Mimi Zohar <zohar@linux.ibm.com>,
	Sven Schnelle <svens@linux.ibm.com>,
	David Howells <dhowells@redhat.com>,
	keyrings@vger.kernel.org, Paul Mackerras <paulus@samba.org>,
	Alexander Gordeev <agordeev@linux.ibm.com>,
	Rob Herring <robh@kernel.org>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Baoquan He <bhe@redhat.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	James Morris <jmorris@namei.org>,
	Lakshmi Ramasubramanian <nramas@linux.microsoft.com>,
	Christian Borntraeger <borntraeger@linux.ibm.com>,
	"Serge E. Hallyn" <serge@hallyn.com>,
	Vasily Gorbik <gor@linux.ibm.com>,
	linux-s390@vger.kernel.org, Heiko Carstens <hca@linux.ibm.com>,
	Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
	Hari Bathini <hbathini@linux.ibm.com>,
	Daniel Axtens <dja@axtens.net>, Philipp Rudo <prudo@redhat.com>,
	Frank van der Linden <fllinden@amazon.com>,
	kexec@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-security-module@vger.kernel.org,
	linux-crypto@vger.kernel.org, Jessica Yu <jeyu@kernel.org>,
	linux-integrity@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
	"David S. Miller" <davem@davemloft.net>,
	Thiago Jung Bauermann <bauerman@linux.ibm.com>,
	buendgen@de.ibm.com
Subject: Re: [PATCH v5 0/6] KEXEC_SIG with appended signature
Date: Wed, 09 Feb 2022 15:46:05 +1100	[thread overview]
Message-ID: <87pmnwlkaa.fsf@mpe.ellerman.id.au> (raw)
In-Reply-To: <YfBd/EDGUx9UIHcb@bombadil.infradead.org>

Luis Chamberlain <mcgrof@kernel.org> writes:
> On Tue, Jan 11, 2022 at 12:37:42PM +0100, Michal Suchanek wrote:
>> Hello,
>> 
>> This is a refresh of the KEXEC_SIG series.
>> 
>> This adds KEXEC_SIG support on powerpc and deduplicates the code dealing
>> with appended signatures in the kernel.
>> 
>> powerpc supports IMA_KEXEC but that's an exception rather than the norm.
>> On the other hand, KEXEC_SIG is portable across platforms.
>> 
>> For distributions to have uniform security features across platforms one
>> option should be used on all platforms.
>> 
>> Thanks
>> 
>> Michal
>> 
>> Previous revision: https://lore.kernel.org/linuxppc-dev/cover.1637862358.git.msuchanek@suse.de/
>> Patched kernel tree: https://github.com/hramrach/kernel/tree/kexec_sig
>> 
>> 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
>
> What tree should this go through? I'd prefer if over through modules
> tree as it can give a chance for Aaron Tomlin to work with this for his
> code refactoring of kernel/module*.c to kernel/module/

Yeah that's fine by me, the arch changes are pretty minimal and unlikely
to conflict much.

cheers