From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Chris Coulson <chris.coulson@canonical.com>
Date: Wed, 16 Nov 2022 14:40:04 +0000
Subject: [PATCH] font: Try opening fonts from the bundled memdisk

Signed-off-by: Robbie Harwood <rharwood@redhat.com>
---
 grub-core/font/font.c | 48 +++++++++++++++++++++++++++++++-----------------
 1 file changed, 31 insertions(+), 17 deletions(-)

diff --git a/grub-core/font/font.c b/grub-core/font/font.c
index e6616e610c..e421d1ae6f 100644
--- a/grub-core/font/font.c
+++ b/grub-core/font/font.c
@@ -409,6 +409,27 @@ read_section_as_short (struct font_file_section *section,
   return 0;
 }
 
+static grub_file_t
+try_open_from_prefix (const char *prefix, const char *filename)
+{
+  grub_file_t file;
+  char *fullname, *ptr;
+
+  fullname = grub_malloc (grub_strlen (prefix) + grub_strlen (filename) + 1
+			  + sizeof ("/fonts/") + sizeof (".pf2"));
+  if (!fullname)
+    return 0;
+  ptr = grub_stpcpy (fullname, prefix);
+  ptr = grub_stpcpy (ptr, "/fonts/");
+  ptr = grub_stpcpy (ptr, filename);
+  ptr = grub_stpcpy (ptr, ".pf2");
+  *ptr = 0;
+
+  file = grub_buffile_open (fullname, GRUB_FILE_TYPE_FONT, 1024);
+  grub_free (fullname);
+  return file;
+}
+
 /* Load a font and add it to the beginning of the global font list.
    Returns 0 upon success, nonzero upon failure.  */
 grub_font_t
@@ -427,25 +448,18 @@ grub_font_load (const char *filename)
     file = grub_buffile_open (filename, GRUB_FILE_TYPE_FONT, 1024);
   else
     {
-      const char *prefix = grub_env_get ("prefix");
-      char *fullname, *ptr;
-      if (!prefix)
+      file = try_open_from_prefix ("(memdisk)", filename);
+      if (!file)
 	{
-	  grub_error (GRUB_ERR_FILE_NOT_FOUND, N_("variable `%s' isn't set"),
-		      "prefix");
-	  goto fail;
+	  const char *prefix = grub_env_get ("prefix");
+	  if (!prefix)
+	    {
+	      grub_error (GRUB_ERR_FILE_NOT_FOUND, N_("variable `%s' isn't set"),
+			  "prefix");
+	      goto fail;
+	    }
+	  file = try_open_from_prefix (prefix, filename);
 	}
-      fullname = grub_malloc (grub_strlen (prefix) + grub_strlen (filename) + 1
-			      + sizeof ("/fonts/") + sizeof (".pf2"));
-      if (!fullname)
-	goto fail;
-      ptr = grub_stpcpy (fullname, prefix);
-      ptr = grub_stpcpy (ptr, "/fonts/");
-      ptr = grub_stpcpy (ptr, filename);
-      ptr = grub_stpcpy (ptr, ".pf2");
-      *ptr = 0;
-      file = grub_buffile_open (fullname, GRUB_FILE_TYPE_FONT, 1024);
-      grub_free (fullname);
     }
   if (!file)
     goto fail;