1 files changed, 97 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/CVE-2022-3775.patch b/meta/recipes-bsp/grub/files/CVE-2022-3775.patch
new file mode 100644
index 0000000000..e2e3f35584
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/CVE-2022-3775.patch
@@ -0,0 +1,97 @@
+From fdbe7209152ad6f09a1166f64f162017f2145ba3 Mon Sep 17 00:00:00 2001
+From: Zhang Boyang <zhangboyang.id@gmail.com>
+Date: Mon, 24 Oct 2022 08:05:35 +0800
+Subject: [PATCH] font: Fix an integer underflow in blit_comb()
+
+The expression (ctx.bounds.height - combining_glyphs[i]->height) / 2 may
+evaluate to a very big invalid value even if both ctx.bounds.height and
+combining_glyphs[i]->height are small integers. For example, if
+ctx.bounds.height is 10 and combining_glyphs[i]->height is 12, this
+expression evaluates to 2147483647 (expected -1). This is because
+coordinates are allowed to be negative but ctx.bounds.height is an
+unsigned int. So, the subtraction operates on unsigned ints and
+underflows to a very big value. The division makes things even worse.
+The quotient is still an invalid value even if converted back to int.
+
+This patch fixes the problem by casting ctx.bounds.height to int. As
+a result the subtraction will operate on int and grub_uint16_t which
+will be promoted to an int. So, the underflow will no longer happen. Other
+uses of ctx.bounds.height (and ctx.bounds.width) are also casted to int,
+to ensure coordinates are always calculated on signed integers.
+
+Fixes: CVE-2022-3775
+
+Reported-by: Daniel Axtens <dja@axtens.net>
+Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
+Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
+
+Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
+
+Upstream-Status: Backport [https://git.savannah.gnu.org/cgit/grub.git/commit/?id=992c06191babc1e109caf40d6a07ec6fdef427af]
+CVE: CVE-2022-3775
+Signed-off-by: Hitendra Prajapati <hprajapati@mvista.com>
+---
+ grub-core/font/font.c | 16 ++++++++--------
+ 1 file changed, 8 insertions(+), 8 deletions(-)
+
+diff --git a/grub-core/font/font.c b/grub-core/font/font.c
+index f110db9..3b76b22 100644
+--- a/grub-core/font/font.c
++++ b/grub-core/font/font.c
+@@ -1200,12 +1200,12 @@ blit_comb (const struct grub_unicode_glyph *glyph_id,
+   ctx.bounds.height = main_glyph->height;
+ 
+   above_rightx = main_glyph->offset_x + main_glyph->width;
+-  above_righty = ctx.bounds.y + ctx.bounds.height;
++  above_righty = ctx.bounds.y + (int) ctx.bounds.height;
+ 
+   above_leftx = main_glyph->offset_x;
+-  above_lefty = ctx.bounds.y + ctx.bounds.height;
++  above_lefty = ctx.bounds.y + (int) ctx.bounds.height;
+ 
+-  below_rightx = ctx.bounds.x + ctx.bounds.width;
++  below_rightx = ctx.bounds.x + (int) ctx.bounds.width;
+   below_righty = ctx.bounds.y;
+ 
+   comb = grub_unicode_get_comb (glyph_id);
+@@ -1218,7 +1218,7 @@ blit_comb (const struct grub_unicode_glyph *glyph_id,
+ 
+       if (!combining_glyphs[i])
+        continue;
+-      targetx = (ctx.bounds.width - combining_glyphs[i]->width) / 2 + ctx.bounds.x;
++      targetx = ((int) ctx.bounds.width - combining_glyphs[i]->width) / 2 + ctx.bounds.x;
+       /* CGJ is to avoid diacritics reordering. */
+       if (comb[i].code
+          == GRUB_UNICODE_COMBINING_GRAPHEME_JOINER)
+@@ -1228,8 +1228,8 @@ blit_comb (const struct grub_unicode_glyph *glyph_id,
+        case GRUB_UNICODE_COMB_OVERLAY:
+          do_blit (combining_glyphs[i],
+                   targetx,
+-                  (ctx.bounds.height - combining_glyphs[i]->height) / 2
+-                  - (ctx.bounds.height + ctx.bounds.y), &ctx);
++                  ((int) ctx.bounds.height - combining_glyphs[i]->height) / 2
++                  - ((int) ctx.bounds.height + ctx.bounds.y), &ctx);
+          if (min_devwidth < combining_glyphs[i]->width)
+            min_devwidth = combining_glyphs[i]->width;
+          break;
+@@ -1302,7 +1302,7 @@ blit_comb (const struct grub_unicode_glyph *glyph_id,
+          /* Fallthrough.  */
+        case GRUB_UNICODE_STACK_ATTACHED_ABOVE:
+          do_blit (combining_glyphs[i], targetx,
+-                  -(ctx.bounds.height + ctx.bounds.y + space
++                  -((int) ctx.bounds.height + ctx.bounds.y + space
+                     + combining_glyphs[i]->height), &ctx);
+          if (min_devwidth < combining_glyphs[i]->width)
+            min_devwidth = combining_glyphs[i]->width;
+@@ -1310,7 +1310,7 @@ blit_comb (const struct grub_unicode_glyph *glyph_id,
+ 
+        case GRUB_UNICODE_COMB_HEBREW_DAGESH:
+          do_blit (combining_glyphs[i], targetx,
+-                  -(ctx.bounds.height / 2 + ctx.bounds.y
++                  -((int) ctx.bounds.height / 2 + ctx.bounds.y
+                     + combining_glyphs[i]->height / 2), &ctx);
+          if (min_devwidth < combining_glyphs[i]->width)
+            min_devwidth = combining_glyphs[i]->width;
+-- 
+2.25.1
+