From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Tue, 13 Jul 2021 13:24:38 +1000
Subject: [PATCH] normal/charset: Fix array out-of-bounds formatting unicode
 for display

In some cases attempting to display arbitrary binary strings leads
to ASAN splats reading the widthspec array out of bounds.

Check the index. If it would be out of bounds, return a width of 1.
I don't know if that's strictly correct, but we're not really expecting
great display of arbitrary binary data, and it's certainly not worse than
an OOB read.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
(cherry picked from commit fdf32abc7a3928852422c0f291d8cd1dd6b34a8d)
(cherry picked from commit f2c10aaf335b88a69885375c4d68ffab2429df77)
(cherry picked from commit 4c942e1ba8d1f1199a58d2eb139022ae22f75cb2)
---
 grub-core/normal/charset.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/grub-core/normal/charset.c b/grub-core/normal/charset.c
index f902b13b44..7b2de12001 100644
--- a/grub-core/normal/charset.c
+++ b/grub-core/normal/charset.c
@@ -395,6 +395,8 @@ grub_unicode_estimate_width (const struct grub_unicode_glyph *c)
 {
   if (grub_unicode_get_comb_type (c->base))
     return 0;
+  if (((unsigned long) (c->base >> 3)) >= ARRAY_SIZE (widthspec))
+    return 1;
   if (widthspec[c->base >> 3] & (1 << (c->base & 7)))
     return 2;
   else
