Fix the 32-bit Arm PE header magic check

Resolves: rhbz#2000756

Signed-off-by: Peter Jones <pjones@redhat.com>

0217-Arm-check-for-the-PE-magic-for-the-compiled-arch.patch

@@ -0,0 +1,61 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Peter Jones <pjones@redhat.com>
+Date: Thu, 9 Sep 2021 10:59:28 -0400
+Subject: [PATCH] Arm: check for the PE magic for the compiled arch
+
+In "arm64: Fix EFI loader kernel image allocation", Ben fixed the kernel
+alignment to match the alignment given in the PE header.  In doing so, a
+check for valid PE magic was added, which was hard-coded to the value
+seen on Aarch64 (GRUB_PE32_PE64_MAGIC).
+
+Unfortunately, this code is shared between 64-bit and 32-bit, and so
+that value broke 32-bit Arm systems.
+
+This patch adds a constant definition for GRUB_PE32_PEXX_MAGIC, which is
+either GRUB_PE32_PE64_MAGIC or GRUB_PE32_PE32_MAGIC, depending on which
+platform is being built, and uses it in the header magic check.
+
+Signed-off-by: Peter Jones <pjones@redhat.com>
+---
+ grub-core/loader/arm64/linux.c | 2 +-
+ include/grub/arm/linux.h       | 1 +
+ include/grub/arm64/linux.h     | 1 +
+ 3 files changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/grub-core/loader/arm64/linux.c b/grub-core/loader/arm64/linux.c
+index 4a252d5e7e9..f18d90bd749 100644
+--- a/grub-core/loader/arm64/linux.c
++++ b/grub-core/loader/arm64/linux.c
+@@ -322,7 +322,7 @@ parse_pe_header (void *kernel, grub_uint64_t *total_size,
+ 
+   pe = (void *)((unsigned long)kernel + lh->hdr_offset);
+ 
+-  if (pe->opt.magic != GRUB_PE32_PE64_MAGIC)
++  if (pe->opt.magic != GRUB_PE32_PEXX_MAGIC)
+     return grub_error(GRUB_ERR_BAD_OS, "Invalid PE optional header magic");
+ 
+   *total_size   = pe->opt.image_size;
+diff --git a/include/grub/arm/linux.h b/include/grub/arm/linux.h
+index b582f67f661..966a5074f53 100644
+--- a/include/grub/arm/linux.h
++++ b/include/grub/arm/linux.h
+@@ -44,6 +44,7 @@ struct grub_arm_linux_pe_header
+ 
+ #if defined(__arm__)
+ # define GRUB_LINUX_ARMXX_MAGIC_SIGNATURE GRUB_LINUX_ARM_MAGIC_SIGNATURE
++# define GRUB_PE32_PEXX_MAGIC GRUB_PE32_PE32_MAGIC
+ # define linux_arch_kernel_header linux_arm_kernel_header
+ # define grub_armxx_linux_pe_header grub_arm_linux_pe_header
+ #endif
+diff --git a/include/grub/arm64/linux.h b/include/grub/arm64/linux.h
+index ea030312df3..422bf2bf24b 100644
+--- a/include/grub/arm64/linux.h
++++ b/include/grub/arm64/linux.h
+@@ -48,6 +48,7 @@ struct grub_arm64_linux_pe_header
+ 
+ #if defined(__aarch64__)
+ # define GRUB_LINUX_ARMXX_MAGIC_SIGNATURE GRUB_LINUX_ARM64_MAGIC_SIGNATURE
++# define GRUB_PE32_PEXX_MAGIC GRUB_PE32_PE64_MAGIC
+ # define linux_arch_kernel_header linux_arm64_kernel_header
+ # define grub_armxx_linux_pe_header grub_arm64_linux_pe_header
+ #endif

grub.patches

@@ -214,3 +214,4 @@ Patch0213: 0213-Remove-outdated-URL-for-BLS-document.patch
 Patch0214: 0214-templates-Check-for-EFI-at-runtime-instead-of-config.patch
 Patch0215: 0215-efi-Print-an-error-if-boot-to-firmware-setup-is-not-.patch
 Patch0216: 0216-arm64-Fix-EFI-loader-kernel-image-allocation.patch
+Patch0217: 0217-Arm-check-for-the-PE-magic-for-the-compiled-arch.patch

grub2.spec

@@ -14,7 +14,7 @@
 Name:		grub2
 Epoch:		1
 Version:	2.06
-Release:	4%{?dist}
+Release:	5%{?dist}
 Summary:	Bootloader with support for Linux, Multiboot and more
 License:	GPLv3+
 URL:		http://www.gnu.org/software/grub/
@@ -523,6 +523,10 @@ mv ${EFI_HOME}/grub.cfg.stb ${EFI_HOME}/grub.cfg
 %endif
 
 %changelog
+* Thu Sep 09 2021 Peter Jones <pjones@redhat.com> - 2.06-5
+- Fix the 32-bit Arm PE header magic check
+  Resolves: rhbz#2000756
+
 * Tue Aug 24 2021 Peter Jones <pjones@redhat.com> - 2.06-4
 - Fix aarch64 kernel alignment.
 - Fix annobin regexp on ppc64le