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Blame SOURCES/0250-normal-charset-Fix-array-out-of-bounds-formatting-un.patch

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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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From: Daniel Axtens <dja@axtens.net>
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Date: Tue, 13 Jul 2021 13:24:38 +1000
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Subject: [PATCH] normal/charset: Fix array out-of-bounds formatting unicode
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 for display
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In some cases attempting to display arbitrary binary strings leads
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to ASAN splats reading the widthspec array out of bounds.
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Check the index. If it would be out of bounds, return a width of 1.
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I don't know if that's strictly correct, but we're not really expecting
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great display of arbitrary binary data, and it's certainly not worse than
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an OOB read.
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Signed-off-by: Daniel Axtens <dja@axtens.net>
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Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
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(cherry picked from commit fdf32abc7a3928852422c0f291d8cd1dd6b34a8d)
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(cherry picked from commit f2c10aaf335b88a69885375c4d68ffab2429df77)
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---
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 grub-core/normal/charset.c | 2 ++
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 1 file changed, 2 insertions(+)
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diff --git a/grub-core/normal/charset.c b/grub-core/normal/charset.c
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index 4dfcc31078..7a5a7c153c 100644
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--- a/grub-core/normal/charset.c
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+++ b/grub-core/normal/charset.c
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@@ -395,6 +395,8 @@ grub_unicode_estimate_width (const struct grub_unicode_glyph *c)
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 {
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   if (grub_unicode_get_comb_type (c->base))
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     return 0;
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+  if (((unsigned long) (c->base >> 3)) >= ARRAY_SIZE (widthspec))
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+    return 1;
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   if (widthspec[c->base >> 3] & (1 << (c->base & 7)))
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     return 2;
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   else