diff options
Diffstat (limited to 'libre/sdl/SDL-1.2.15-CVE-2019-7635-Reject-BMP-images-with-pixel-colors-ou.patch')
| -rw-r--r-- | libre/sdl/SDL-1.2.15-CVE-2019-7635-Reject-BMP-images-with-pixel-colors-ou.patch | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/libre/sdl/SDL-1.2.15-CVE-2019-7635-Reject-BMP-images-with-pixel-colors-ou.patch b/libre/sdl/SDL-1.2.15-CVE-2019-7635-Reject-BMP-images-with-pixel-colors-ou.patch new file mode 100644 index 000000000..fb899d5f3 --- /dev/null +++ b/libre/sdl/SDL-1.2.15-CVE-2019-7635-Reject-BMP-images-with-pixel-colors-ou.patch @@ -0,0 +1,67 @@ +From beef32b0e510371f3c968d22a1e3d48abbf366c6 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com> +Date: Tue, 19 Feb 2019 14:52:52 +0100 +Subject: [PATCH] CVE-2019-7635: Reject BMP images with pixel colors out the + palette +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +If a 1-, 4-, or 8-bit per pixel BMP image declares less used colors +than the palette offers an SDL_Surface with a palette of the indicated +number of used colors is created. If some of the image's pixel +refer to a color number higher then the maximal used colors, a subsequent +bliting operation on the surface will look up a color past a blit map +(that is based on the palette) memory. I.e. passing such SDL_Surface +to e.g. an SDL_DisplayFormat() function will result in a buffer overread in +a blit function. + +This patch fixes it by validing each pixel's color to be less than the +maximal color number in the palette. A validation failure raises an +error from a SDL_LoadBMP_RW() function. + +CVE-2019-7635 +https://bugzilla.libsdl.org/show_bug.cgi?id=4498 + +Signed-off-by: Petr Písař <ppisar@redhat.com> +--- + src/video/SDL_bmp.c | 16 ++++++++++++++++ + 1 file changed, 16 insertions(+) + +diff --git a/src/video/SDL_bmp.c b/src/video/SDL_bmp.c +index 3accded..8eadc5f 100644 +--- a/src/video/SDL_bmp.c ++++ b/src/video/SDL_bmp.c +@@ -300,6 +300,12 @@ SDL_Surface * SDL_LoadBMP_RW (SDL_RWops *src, int freesrc) + } + *(bits+i) = (pixel>>shift); + pixel <<= ExpandBMP; ++ if ( bits[i] >= biClrUsed ) { ++ SDL_SetError( ++ "A BMP image contains a pixel with a color out of the palette"); ++ was_error = SDL_TRUE; ++ goto done; ++ } + } } + break; + +@@ -310,6 +316,16 @@ SDL_Surface * SDL_LoadBMP_RW (SDL_RWops *src, int freesrc) + was_error = SDL_TRUE; + goto done; + } ++ if ( 8 == biBitCount && palette && biClrUsed < (1 << biBitCount ) ) { ++ for ( i=0; i<surface->w; ++i ) { ++ if ( bits[i] >= biClrUsed ) { ++ SDL_SetError( ++ "A BMP image contains a pixel with a color out of the palette"); ++ was_error = SDL_TRUE; ++ goto done; ++ } ++ } ++ } + #if SDL_BYTEORDER == SDL_BIG_ENDIAN + /* Byte-swap the pixels if needed. Note that the 24bpp + case has already been taken care of above. */ +-- +2.20.1 + |