[PATCH v5 0/3] use more system keyrings to verify arm64 kdump kernel image signature

[Michal Suchánek]

On Fri, Apr 08, 2022 at 03:17:19PM +0800, Baoquan He wrote:
> Hi Coiby,
> 
> On 04/01/22 at 09:31am, Coiby Xu wrote:
> > Currently, a problem faced by arm64 is if a kernel image is signed by a
> > MOK key, loading it via the kexec_file_load() system call would be
> > rejected with the error "Lockdown: kexec: kexec of unsigned images is
> > restricted; see man kernel_lockdown.7".
> > 
> > This patch set allows arm64 to use more system keyrings to verify kdump 
> > kernel image signature by making the existing code in x64 public.
> 
> Thanks for updating. It would be great to tell why the problem is
> met, then allow arm64 to use more system keyrings can solve it.

The reason is that MOK keys are (if anywhere) linked to the secondary
keyring, and only primary keyring is used on arm64.

Thanks

Michal

> 
> Meanwhile, I noticed Michal also posted a patchset to address the same
> issue, while he tries to make it work on s390 too. Could you check and
> consider if these two patches can be integrated?
> 
> [PATCH 0/4] Unifrom keyring support across architectures and functions
> https://lore.kernel.org/lkml/cover.1644953683.git.msuchanek@suse.de/
> 
> Thanks
> Baoquan
> 
> > 
> > v5:
> >  - improve commit message [Baoquan]
> > 
> > v4:
> >  - fix commit reference format issue and other checkpatch.pl warnings [Baoquan]
> > 
> > v3:
> >  - s/arch_kexec_kernel_verify_pe_sig/kexec_kernel_verify_pe_sig [Eric]
> >  - clean up arch_kexec_kernel_verify_sig [Eric]
> > 
> > v2:
> >  - only x86_64 and arm64 need to enable PE file signature check [Dave]
> > 
> > Coiby Xu (3):
> >   kexec: clean up arch_kexec_kernel_verify_sig
> >   kexec, KEYS: make the code in bzImage64_verify_sig generic
> >   arm64: kexec_file: use more system keyrings to verify kernel image
> >     signature
> > 
> >  arch/arm64/kernel/kexec_image.c   |  4 +--
> >  arch/x86/kernel/kexec-bzimage64.c | 13 +-------
> >  include/linux/kexec.h             |  7 +++--
> >  kernel/kexec_file.c               | 51 ++++++++++++++++++-------------
> >  4 files changed, 37 insertions(+), 38 deletions(-)
> > 
> > -- 
> > 2.34.1
> > 
>