diff options
Diffstat (limited to 'meta/recipes-bsp/grub/files/0001-font-Fix-size-overflow-in-grub_font_get_glyph_intern.patch')
| -rw-r--r-- | meta/recipes-bsp/grub/files/0001-font-Fix-size-overflow-in-grub_font_get_glyph_intern.patch | 115 |
1 files changed, 115 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 |