File 0021-normal-charset-Fix-array-out-of-bounds-for... of Package grub2.26835

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File 0021-normal-charset-Fix-array-out-of-bounds-formatting-un.patch of Package grub2.26835

From f3c0abfc30c4917970ffbd3890a4dbf2ae816397 Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Tue, 13 Jul 2021 13:24:38 +1000
Subject: [PATCH 21/37] 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>
---
 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 4dfcc31078..7a5a7c153c 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
-- 
2.34.1

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