grub2: backport patch to fix CVE-2022-2601 CVE-2022-3775

Backport patch from upstream to solve CVE-2022-2601 CVE-2022-3775 dependency:
font: Fix size overflow in grub_font_get_glyph_internal()
(https://git.savannah.gnu.org/cgit/grub.git/commit/?id=9c76ec09ae08155df27cd237eaea150b4f02f532)

Backport patch from upstream to fix following CVEs:
CVE-2022-2601: font: Fix several integer overflows in grub_font_construct_glyph()
(https://git.savannah.gnu.org/cgit/grub.git/commit/?id=768e1ef2fc159f6e14e7246e4be09363708ac39e)
CVE-2022-3775: font: Fix an integer underflow in blit_comb()
(https://git.savannah.gnu.org/cgit/grub.git/commit/?id=992c06191babc1e109caf40d6a07ec6fdef427af)

(From OE-Core rev: fa5a42150098be892246146456faed778e28ef94)

Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Liwei Song <liwei.song@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

4 files changed, 298 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/0001-font-Fix-size-overflow-in-grub_font_get_glyph_intern.patch b/meta/recipes-bsp/grub/files/0001-font-Fix-size-overflow-in-grub_font_get_glyph_intern.patch
new file mode 100644
index 0000000000..efa00a3c6c
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/0001-font-Fix-size-overflow-in-grub_font_get_glyph_intern.patch
@@ -0,0 +1,115 @@
+From 1f511ae054fe42dce7aedfbfe0f234fa1e0a7a3e Mon Sep 17 00:00:00 2001
+From: Zhang Boyang <zhangboyang.id@gmail.com>
+Date: Fri, 5 Aug 2022 00:51:20 +0800
+Subject: [PATCH] font: Fix size overflow in grub_font_get_glyph_internal()
+
+The length of memory allocation and file read may overflow. This patch
+fixes the problem by using safemath macros.
+
+There is a lot of code repetition like "(x * y + 7) / 8". It is unsafe
+if overflow happens. This patch introduces grub_video_bitmap_calc_1bpp_bufsz().
+It is safe replacement for such code. It has safemath-like prototype.
+
+This patch also introduces grub_cast(value, pointer), it casts value to
+typeof(*pointer) then store the value to *pointer. It returns true when
+overflow occurs or false if there is no overflow. The semantics of arguments
+and return value are designed to be consistent with other safemath macros.
+
+Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
+Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
+
+Upstream-Status: Backport from
+[https://git.savannah.gnu.org/cgit/grub.git/commit/?id=9c76ec09ae08155df27cd237eaea150b4f02f532]
+
+Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
+
+---
+ grub-core/font/font.c   | 17 +++++++++++++----
+ include/grub/bitmap.h   | 18 ++++++++++++++++++
+ include/grub/safemath.h |  2 ++
+ 3 files changed, 33 insertions(+), 4 deletions(-)
+
+diff --git a/grub-core/font/font.c b/grub-core/font/font.c
+index d09bb38..876b5b6 100644
+--- a/grub-core/font/font.c
++++ b/grub-core/font/font.c
+@@ -739,7 +739,8 @@ grub_font_get_glyph_internal (grub_font_t font, grub_uint32_t code)
+       grub_int16_t xoff;
+       grub_int16_t yoff;
+       grub_int16_t dwidth;
+-      int len;
++      grub_ssize_t len;
++      grub_size_t sz;
+ 
+       if (index_entry->glyph)
+        /* Return cached glyph.  */
+@@ -766,9 +767,17 @@ grub_font_get_glyph_internal (grub_font_t font, grub_uint32_t code)
+          return 0;
+        }
+ 
+-      len = (width * height + 7) / 8;
+-      glyph = grub_malloc (sizeof (struct grub_font_glyph) + len);
+-      if (!glyph)
++      /* Calculate real struct size of current glyph. */
++      if (grub_video_bitmap_calc_1bpp_bufsz (width, height, &len) ||
++         grub_add (sizeof (struct grub_font_glyph), len, &sz))
++       {
++         remove_font (font);
++         return 0;
++       }
++
++      /* Allocate and initialize the glyph struct. */
++      glyph = grub_malloc (sz);
++      if (glyph == NULL)
+        {
+          remove_font (font);
+          return 0;
+diff --git a/include/grub/bitmap.h b/include/grub/bitmap.h
+index 5728f8c..0d9603f 100644
+--- a/include/grub/bitmap.h
++++ b/include/grub/bitmap.h
+@@ -23,6 +23,7 @@
+ #include <grub/symbol.h>
+ #include <grub/types.h>
+ #include <grub/video.h>
++#include <grub/safemath.h>
+ 
+ struct grub_video_bitmap
+ {
+@@ -79,6 +80,23 @@ grub_video_bitmap_get_height (struct grub_video_bitmap *bitmap)
+   return bitmap->mode_info.height;
+ }
+ 
++/*
++ * Calculate and store the size of data buffer of 1bit bitmap in result.
++ * Equivalent to "*result = (width * height + 7) / 8" if no overflow occurs.
++ * Return true when overflow occurs or false if there is no overflow.
++ * This function is intentionally implemented as a macro instead of
++ * an inline function. Although a bit awkward, it preserves data types for
++ * safemath macros and reduces macro side effects as much as possible.
++ *
++ * XXX: Will report false overflow if width * height > UINT64_MAX.
++ */
++#define grub_video_bitmap_calc_1bpp_bufsz(width, height, result) \
++({ \
++  grub_uint64_t _bitmap_pixels; \
++  grub_mul ((width), (height), &_bitmap_pixels) ? 1 : \
++    grub_cast (_bitmap_pixels / GRUB_CHAR_BIT + !!(_bitmap_pixels % GRUB_CHAR_BIT), (result)); \
++})
++
+ void EXPORT_FUNC (grub_video_bitmap_get_mode_info) (struct grub_video_bitmap *bitmap,
+                                                    struct grub_video_mode_info *mode_info);
+ 
+diff --git a/include/grub/safemath.h b/include/grub/safemath.h
+index c17b89b..bb0f826 100644
+--- a/include/grub/safemath.h
++++ b/include/grub/safemath.h
+@@ -30,6 +30,8 @@
+ #define grub_sub(a, b, res)    __builtin_sub_overflow(a, b, res)
+ #define grub_mul(a, b, res)    __builtin_mul_overflow(a, b, res)
+ 
++#define grub_cast(a, res)      grub_add ((a), 0, (res))
++
+ #else
+ #error gcc 5.1 or newer or clang 3.8 or newer is required
+ #endif
diff --git a/meta/recipes-bsp/grub/files/CVE-2022-2601.patch b/meta/recipes-bsp/grub/files/CVE-2022-2601.patch
new file mode 100644
index 0000000000..727c509694
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/CVE-2022-2601.patch
@@ -0,0 +1,85 @@
+From e8060722acf0bcca037982d7fb29472363ccdfd4 Mon Sep 17 00:00:00 2001
+From: Zhang Boyang <zhangboyang.id@gmail.com>
+Date: Fri, 5 Aug 2022 01:58:27 +0800
+Subject: [PATCH] font: Fix several integer overflows in
+ grub_font_construct_glyph()
+
+This patch fixes several integer overflows in grub_font_construct_glyph().
+Glyphs of invalid size, zero or leading to an overflow, are rejected.
+The inconsistency between "glyph" and "max_glyph_size" when grub_malloc()
+returns NULL is fixed too.
+
+Fixes: CVE-2022-2601
+
+Reported-by: Zhang Boyang <zhangboyang.id@gmail.com>
+Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
+Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
+
+Upstream-Status: Backport from
+[https://git.savannah.gnu.org/cgit/grub.git/commit/?id=768e1ef2fc159f6e14e7246e4be09363708ac39e]
+CVE: CVE-2022-2601
+
+Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
+
+---
+ grub-core/font/font.c | 29 +++++++++++++++++------------
+ 1 file changed, 17 insertions(+), 12 deletions(-)
+
+diff --git a/grub-core/font/font.c b/grub-core/font/font.c
+index 876b5b6..0ff5525 100644
+--- a/grub-core/font/font.c
++++ b/grub-core/font/font.c
+@@ -1515,6 +1515,7 @@ grub_font_construct_glyph (grub_font_t hinted_font,
+   struct grub_video_signed_rect bounds;
+   static struct grub_font_glyph *glyph = 0;
+   static grub_size_t max_glyph_size = 0;
++  grub_size_t cur_glyph_size;
+ 
+   ensure_comb_space (glyph_id);
+ 
+@@ -1531,29 +1532,33 @@ grub_font_construct_glyph (grub_font_t hinted_font,
+   if (!glyph_id->ncomb && !glyph_id->attributes)
+     return main_glyph;
+ 
+-  if (max_glyph_size < sizeof (*glyph) + (bounds.width * bounds.height + GRUB_CHAR_BIT - 1) / GRUB_CHAR_BIT)
++  if (grub_video_bitmap_calc_1bpp_bufsz (bounds.width, bounds.height, &cur_glyph_size) ||
++      grub_add (sizeof (*glyph), cur_glyph_size, &cur_glyph_size))
++    return main_glyph;
++
++  if (max_glyph_size < cur_glyph_size)
+     {
+       grub_free (glyph);
+-      max_glyph_size = (sizeof (*glyph) + (bounds.width * bounds.height + GRUB_CHAR_BIT - 1) / GRUB_CHAR_BIT) * 2;
+-      if (max_glyph_size < 8)
+-       max_glyph_size = 8;
+-      glyph = grub_malloc (max_glyph_size);
++      if (grub_mul (cur_glyph_size, 2, &max_glyph_size))
++       max_glyph_size = 0;
++      glyph = max_glyph_size > 0 ? grub_malloc (max_glyph_size) : NULL;
+     }
+   if (!glyph)
+     {
++      max_glyph_size = 0;
+       grub_errno = GRUB_ERR_NONE;
+       return main_glyph;
+     }
+ 
+-  grub_memset (glyph, 0, sizeof (*glyph)
+-              + (bounds.width * bounds.height
+-                 + GRUB_CHAR_BIT - 1) / GRUB_CHAR_BIT);
++  grub_memset (glyph, 0, cur_glyph_size);
+ 
+   glyph->font = main_glyph->font;
+-  glyph->width = bounds.width;
+-  glyph->height = bounds.height;
+-  glyph->offset_x = bounds.x;
+-  glyph->offset_y = bounds.y;
++  if (bounds.width == 0 || bounds.height == 0 ||
++      grub_cast (bounds.width, &glyph->width) ||
++      grub_cast (bounds.height, &glyph->height) ||
++      grub_cast (bounds.x, &glyph->offset_x) ||
++      grub_cast (bounds.y, &glyph->offset_y))
++    return main_glyph;
+ 
+   if (glyph_id->attributes & GRUB_UNICODE_GLYPH_ATTRIBUTE_MIRROR)
+     grub_font_blit_glyph_mirror (glyph, main_glyph,
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..853efd0486
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/CVE-2022-3775.patch
@@ -0,0 +1,95 @@
+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>
+
+Upstream-Status: Backport from
+[https://git.savannah.gnu.org/cgit/grub.git/commit/?id=992c06191babc1e109caf40d6a07ec6fdef427af]
+CVE: CVE-2022-3775
+
+Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.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 0ff5525..7b1cbde 100644
+--- a/grub-core/font/font.c
++++ b/grub-core/font/font.c
+@@ -1206,12 +1206,12 @@ 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);
+@@ -1224,7 +1224,7 @@ 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)
+@@ -1234,8 +1234,8 @@ 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;
+@@ -1308,7 +1308,7 @@ 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;
+@@ -1316,7 +1316,7 @@ 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;
diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc
index e819cb9775..bf7aba6b1c 100644
--- a/meta/recipes-bsp/grub/grub2.inc
+++ b/meta/recipes-bsp/grub/grub2.inc
@@ -37,6 +37,9 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \
            file://loader-efi-chainloader-Simplify-the-loader-state.patch \
            file://commands-boot-Add-API-to-pass-context-to-loader.patch \
            file://CVE-2022-28736-loader-efi-chainloader-Use-grub_loader_set_ex.patch\
+           file://0001-font-Fix-size-overflow-in-grub_font_get_glyph_intern.patch \
+           file://CVE-2022-2601.patch \
+           file://CVE-2022-3775.patch \
 "
 
 SRC_URI[sha256sum] = "23b64b4c741569f9426ed2e3d0e6780796fca081bee4c99f62aa3f53ae803f5f"