From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Peter Jones <[email protected]>
Date: Tue, 11 Oct 2022 17:00:50 -0400
Subject: [PATCH] x86-efi: Fix an incorrect array size in kernel allocation

In 81a6ebf62bbe166ddc968463df2e8bd481bf697c ("efi: split allocation
policy for kernel vs initrd memories."), I introduced a split in the
kernel allocator to allow for different dynamic policies for the kernel
and the initrd allocations.

Unfortunately, that change increased the size of the policy data used to
make decisions, but did not change the size of the temporary storage we
use to back it up and restore.  This results in some of .data getting
clobbered at runtime, and hilarity ensues.

This patch makes the size of the backup storage be based on the size of
the initial policy data.

Signed-off-by: Peter Jones <[email protected]>
(cherry picked from commit 37747b22342499a798ca3a8895770cd93b6e1258)
(cherry picked from commit 72713ce761720235c86bbda412480c97b2892e00)
---
 grub-core/loader/i386/efi/linux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/grub-core/loader/i386/efi/linux.c b/grub-core/loader/i386/efi/linux.c
index 4d39023792..3d55f8b8d2 100644
--- a/grub-core/loader/i386/efi/linux.c
+++ b/grub-core/loader/i386/efi/linux.c
@@ -92,7 +92,7 @@ static struct allocation_choice max_addresses[] =
       { INITRD_MEM, GRUB_EFI_MAX_ALLOCATION_ADDRESS, GRUB_EFI_ALLOCATE_MAX_ADDRESS },
     { NO_MEM, 0, 0 }
   };
-static struct allocation_choice saved_addresses[4];
+static struct allocation_choice saved_addresses[sizeof(max_addresses) / sizeof(max_addresses[0])];
 
 #define save_addresses() grub_memcpy(saved_addresses, max_addresses, sizeof(max_addresses))
 #define restore_addresses() grub_memcpy(max_addresses, saved_addresses, sizeof(max_addresses))