integ/grub/grub-efi/debian/patches/0033-font-Assign-null_font-to-glyphs-in-ascii_font_glyph.patch
Li Zhou d10d6fb187 grub2/grub-efi: fix CVE-2022-2601/CVE-2022-3775
Porting patches from grub2_2.06-3~deb11u4 to fix
CVE-2022-2601/CVE-2022-3775.

The source code of grub2_2.06-3~deb11u4 is from:
https://snapshot.debian.org/archive/debian/20221124T030451Z/
pool/main/g/grub2/grub2_2.06-3~deb11u4.debian.tar.xz

Refer to above source code and this link for the fix:
https://lists.gnu.org/archive/html/grub-devel/2022-11/msg00059.html

The 1st patch in the list is for making proper context for the 14
patches of the 2 CVEs. No content changes for all the patches from
debian release.

We do this because grub2/grub-efi is ported from wrlinux for
secure boot bringing up.

Test plan:
 - PASS: build grub2/grub-efi.
 - PASS: build-image and install and boot up on lab/qemu.
 - PASS: check that the "stx.N" version number is right for both
         bios(grub2 ver) and uefi(grub-efi ver) boot.

Closes-bug: 2020730

Signed-off-by: Li Zhou <li.zhou@windriver.com>
Change-Id: Ia6c58a2021a786ef92f760b3cfe035fbccedacf7
2023-06-01 06:08:44 -04:00

37 lines
1.4 KiB
Diff

From dd539d695482069d28b40f2d3821f710cdcf6ee6 Mon Sep 17 00:00:00 2001
From: Zhang Boyang <zhangboyang.id@gmail.com>
Date: Fri, 28 Oct 2022 17:29:16 +0800
Subject: [PATCH 13/14] font: Assign null_font to glyphs in ascii_font_glyph[]
The calculations in blit_comb() need information from glyph's font, e.g.
grub_font_get_xheight(main_glyph->font). However, main_glyph->font is
NULL if main_glyph comes from ascii_font_glyph[]. Therefore
grub_font_get_*() crashes because of NULL pointer.
There is already a solution, the null_font. So, assign it to those glyphs
in ascii_font_glyph[].
Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
grub-core/font/font.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/grub-core/font/font.c b/grub-core/font/font.c
index cf15dc2f9..3821937e6 100644
--- a/grub-core/font/font.c
+++ b/grub-core/font/font.c
@@ -137,7 +137,7 @@ ascii_glyph_lookup (grub_uint32_t code)
ascii_font_glyph[current]->offset_x = 0;
ascii_font_glyph[current]->offset_y = -2;
ascii_font_glyph[current]->device_width = 8;
- ascii_font_glyph[current]->font = NULL;
+ ascii_font_glyph[current]->font = &null_font;
grub_memcpy (ascii_font_glyph[current]->bitmap,
&ascii_bitmaps[current * ASCII_BITMAP_SIZE],
--
2.30.2