File 0001-kern-efi-sb-Add-chainloaded-image-as-shim-s-verifiab.patch of Package grub2
From 6d05264eeceaa2be991093d7fc31b78130bf5453 Mon Sep 17 00:00:00 2001
From: Michael Chang <email@example.com>
Date: Fri, 5 Mar 2021 21:48:53 +0800
Subject: [PATCH] kern/efi/sb: Add chainloaded image as shim's verifiable
While attempting to dual boot Microsoft Windows with UEFI chainloader,
it failed with below error when UEFI Secure Boot was enabled:
error ../../grub-core/kern/verifiers.c:119:verification requested but
nobody cares: /EFI/Microsoft/Boot/bootmgfw.efi.
It is a regression, as previously it worked without any problem.
It turns out chainloading PE image has been locked down by commit
578c95298 (kern: Add lockdown support). However, we should consider it
as verifiable object by shim to allow booting in UEFI Secure Boot mode.
The chainloaded PE image could also have trusted signature created by
vendor with their pubkey cert in db. For that matters it's usage should
not be locked down under UEFI Secure Boot, and instead shim should be
allowed to validate a PE binary signature before running it.
Fixes: 578c95298 (kern: Add lockdown support)
Signed-off-by: Michael Chang <firstname.lastname@example.org>
Reviewed-by: Daniel Kiper <email@example.com>
grub-core/kern/efi/sb.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/grub-core/kern/efi/sb.c b/grub-core/kern/efi/sb.c
index 41dadcd14..96d237722 100644
@@ -129,6 +129,7 @@ shim_lock_verifier_init (grub_file_t io __attribute__ ((unused)),
+ case GRUB_FILE_TYPE_EFI_CHAINLOADED_IMAGE:
*flags = GRUB_VERIFY_FLAGS_SINGLE_CHUNK;
/* Fall through. */