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

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File 0021-normal-charset-Fix-array-out-of-bounds-formatting-un.patch of Package grub2 (Revision 4422d96241a78721e2258424ed423d1e)

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From 4dd3cf4f51e21158b291d16e30050795589dc0a0 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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File 0021-normal-charset-Fix-array-out-of-bounds-formatting-un.patch of Package grub2 (Revision 4422d96241a78721e2258424ed423d1e)

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