File 0016-normal-charset-Fix-array-out-of-bounds-for... of Package grub2

Overview Repositories Revisions Requests Users Attributes Meta

File 0016-normal-charset-Fix-array-out-of-bounds-formatting-un.patch of Package grub2 (Revision 3191088aeb5fea8f4b8ae2f0326a83df)

Currently displaying revision 3191088aeb5fea8f4b8ae2f0326a83df , Show latest

From cfe96e5c432b58726047f4d94f106f58855db1e2 Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Tue, 13 Jul 2021 13:24:38 +1000
Subject: [PATCH 16/32] 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

Places

File 0016-normal-charset-Fix-array-out-of-bounds-formatting-un.patch of Package grub2 (Revision 3191088aeb5fea8f4b8ae2f0326a83df)

Places