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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Peter Jones <pjones@redhat.com>
Date: Wed, 9 Feb 2022 16:08:20 -0500
Subject: [PATCH] EFI: allocate kernel in EFI_RUNTIME_SERVICES_CODE instead of
 EFI_LOADER_DATA.

On some of the firmwares with more security mitigations, EFI_LOADER_DATA
doesn't get you executable memory, and we take a fault and reboot when
we enter kernel.

This patch correctly allocates the kernel code as EFI_RUNTIME_SERVICES_CODE
rather than EFI_LOADER_DATA.

Signed-off-by: Peter Jones <pjones@redhat.com>
[rharwood: use kernel_size]
Signed-off-by: Robbie Harwood <rharwood@redhat.com>
---
 grub-core/loader/i386/efi/linux.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/grub-core/loader/i386/efi/linux.c b/grub-core/loader/i386/efi/linux.c
index 9e5c11ac69..92b2fb5091 100644
--- a/grub-core/loader/i386/efi/linux.c
+++ b/grub-core/loader/i386/efi/linux.c
@@ -86,7 +86,9 @@ kernel_free(void *addr, grub_efi_uintn_t size)
 }
 
 static void *
-kernel_alloc(grub_efi_uintn_t size, const char * const errmsg)
+kernel_alloc(grub_efi_uintn_t size,
+	     grub_efi_memory_type_t memtype,
+	     const char * const errmsg)
 {
   void *addr = 0;
   unsigned int i;
@@ -112,7 +114,7 @@ kernel_alloc(grub_efi_uintn_t size, const char * const errmsg)
       prev_max = max;
       addr = grub_efi_allocate_pages_real (max, pages,
 					   max_addresses[i].alloc_type,
-					   GRUB_EFI_LOADER_DATA);
+					   memtype);
       if (addr)
 	grub_dprintf ("linux", "Allocated at %p\n", addr);
     }
@@ -242,7 +244,8 @@ grub_cmd_initrd (grub_command_t cmd, int argc, char *argv[])
 	}
     }
 
-  initrd_mem = kernel_alloc(size, N_("can't allocate initrd"));
+  initrd_mem = kernel_alloc(size, GRUB_EFI_RUNTIME_SERVICES_DATA,
+			    N_("can't allocate initrd"));
   if (initrd_mem == NULL)
     goto fail;
   grub_dprintf ("linux", "initrd_mem = %p\n", initrd_mem);
@@ -393,7 +396,8 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
     }
 #endif
 
-  params = kernel_alloc (sizeof(*params), "cannot allocate kernel parameters");
+  params = kernel_alloc (sizeof(*params), GRUB_EFI_RUNTIME_SERVICES_DATA,
+			 "cannot allocate kernel parameters");
   if (!params)
     goto fail;
   grub_dprintf ("linux", "params = %p\n", params);
@@ -415,7 +419,9 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
   grub_dprintf ("linux", "new lh is at %p\n", lh);
 
   grub_dprintf ("linux", "setting up cmdline\n");
-  cmdline = kernel_alloc (lh->cmdline_size + 1, N_("can't allocate cmdline"));
+  cmdline = kernel_alloc (lh->cmdline_size + 1,
+			  GRUB_EFI_RUNTIME_SERVICES_DATA,
+			  N_("can't allocate cmdline"));
   if (!cmdline)
     goto fail;
   grub_dprintf ("linux", "cmdline = %p\n", cmdline);
@@ -461,7 +467,8 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
   max_addresses[1].addr = GRUB_EFI_MAX_ALLOCATION_ADDRESS;
   max_addresses[2].addr = GRUB_EFI_MAX_ALLOCATION_ADDRESS;
   kernel_size = lh->init_size;
-  kernel_mem = kernel_alloc (kernel_size, N_("can't allocate kernel"));
+  kernel_mem = kernel_alloc (kernel_size, GRUB_EFI_RUNTIME_SERVICES_CODE,
+			     N_("can't allocate kernel"));
   restore_addresses();
   if (!kernel_mem)
     goto fail;