Re: [PATCH 5.15 0/6] arm64: kexec_file: use more system keyrings to verify kernel image signature + dependencies

From: "Michal Suchánek" <msuchanek@suse.de>
To: Mimi Zohar <zohar@linux.ibm.com>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	Heiko Carstens <hca@linux.ibm.com>,
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	James Morse <james.morse@arm.com>,
	AKASHI Takahiro <takahiro.akashi@linaro.org>
Subject: Re: [PATCH 5.15 0/6] arm64: kexec_file: use more system keyrings to verify kernel image signature + dependencies
Date: Fri, 23 Sep 2022 21:16:50 +0200	[thread overview]
Message-ID: <20220923191650.GX28810@kitsune.suse.cz> (raw)
In-Reply-To: <67337b60a4d3cae00794d3cfd0e5add9899f18b7.camel@linux.ibm.com>

Hello,

On Fri, Sep 23, 2022 at 03:03:36PM -0400, Mimi Zohar wrote:
> On Fri, 2022-09-23 at 19:10 +0200, Michal Suchanek wrote:
> > Hello,
> > 
> > this is backport of commit 0d519cadf751
> > ("arm64: kexec_file: use more system keyrings to verify kernel image signature")
> > to table 5.15 tree including the preparatory patches.
> > 
> > Some patches needed minor adjustment for context.
> 
> In general when backporting this patch set, there should be a
> dependency on backporting these commits as well.  In this instance for
> linux-5.15.y, they've already been backported.
> 
> 543ce63b664e ("lockdown: Fix kexec lockdown bypass with ima policy")
> af16df54b89d ("ima: force signature verification when CONFIG_KEXEC_SIG is configured")

Thanks for bringing these up. It might be in general useful to backport
these fixes as well.

However, this patchset does one very specific thing: it lifts the x86
kexec_file signature verification to arch-independent and uses it on
arm64 to unify all features (and any existing warts) between EFI
architectures.

So unless I am missing something the fixes you pointed out are
completely independent of this.

Thanks

Michal