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-rw-r--r--main/sdl/0001-CVE-2019-7635.patch53
1 files changed, 53 insertions, 0 deletions
diff --git a/main/sdl/0001-CVE-2019-7635.patch b/main/sdl/0001-CVE-2019-7635.patch
new file mode 100644
index 0000000000..ebf8b91e7f
--- /dev/null
+++ b/main/sdl/0001-CVE-2019-7635.patch
@@ -0,0 +1,53 @@
+CVE-2019-7635: Reject BMP images with pixel colors out the palette
+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>
+
+diff -r a936f9bd3e38 -r f1f5878be5db src/video/SDL_bmp.c
+--- a/src/video/SDL_bmp.c Mon Jun 10 09:25:05 2019 -0700
++++ b/src/video/SDL_bmp.c Tue Jun 11 06:28:12 2019 -0700
+@@ -308,6 +308,12 @@
+ }
+ *(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;
+
+@@ -318,6 +324,16 @@
+ 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. */
+