diff options
Diffstat (limited to 'poky/meta/recipes-bsp/grub/files/CVE-2022-3775.patch')
-rw-r--r-- | poky/meta/recipes-bsp/grub/files/CVE-2022-3775.patch | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/poky/meta/recipes-bsp/grub/files/CVE-2022-3775.patch b/poky/meta/recipes-bsp/grub/files/CVE-2022-3775.patch new file mode 100644 index 0000000000..853efd0486 --- /dev/null +++ b/poky/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; |