grub2/0212-loader-efi-chainloader-grub_load_and_start_image-doe.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Chris Coulson <chris.coulson@canonical.com>
Date: Thu, 28 Apr 2022 21:53:36 +0100
Subject: [PATCH] loader/efi/chainloader: grub_load_and_start_image doesn't
 load and start

grub_load_and_start_image only loads an image - it still requires the
caller to start it. This renames it to grub_load_image.

It's called from 2 places:
- grub_cmd_chainloader when not using the shim protocol.
- grub_secureboot_chainloader_boot if handle_image returns an error.
In this case, the image is loaded and then nothing else happens which
seems strange. I assume the intention is that it falls back to LoadImage
and StartImage if handle_image fails, so I've made it do that.

Signed-off-by: Chris Coulson <chris.coulson@canonical.com>
(cherry picked from commit b4d70820a65c00561045856b7b8355461a9545f6)
---
 grub-core/loader/efi/chainloader.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/grub-core/loader/efi/chainloader.c b/grub-core/loader/efi/chainloader.c
index 644cd2e56f..d3bf02ed8a 100644
--- a/grub-core/loader/efi/chainloader.c
+++ b/grub-core/loader/efi/chainloader.c
@@ -841,7 +841,7 @@ grub_secureboot_chainloader_unload (void)
 }
 
 static grub_err_t
-grub_load_and_start_image(void *boot_image)
+grub_load_image(void *boot_image)
 {
   grub_efi_boot_services_t *b;
   grub_efi_status_t status;
@@ -883,13 +883,23 @@ grub_load_and_start_image(void *boot_image)
 static grub_err_t
 grub_secureboot_chainloader_boot (void)
 {
+  grub_efi_boot_services_t *b;
   int rc;
+
   rc = handle_image ((void *)(unsigned long)address, fsize);
   if (rc == 0)
     {
-      grub_load_and_start_image((void *)(unsigned long)address);
+      /* We weren't able to attempt to execute the image, so fall back
+       * to LoadImage / StartImage.
+       */
+      rc = grub_load_image((void *)(unsigned long)address);
+      if (rc == 0)
+        grub_chainloader_boot ();
     }
 
+  b = grub_efi_system_table->boot_services;
+  efi_call_1 (b->unload_image, image_handle);
+
   grub_loader_unset ();
   return grub_errno;
 }
@@ -1091,7 +1101,7 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)),
     }
   else
     {
-      grub_load_and_start_image(boot_image);
+      grub_load_image(boot_image);
       grub_file_close (file);
       grub_device_close (dev);
       grub_loader_set (grub_chainloader_boot, grub_chainloader_unload, 0);