Commit 33ceac2afc3608be2d12b3dece071a91e34c3062
2022-09-15T09:47:07
Reject 'COLR' table if version is 1 but header too small. * src/sfnt/ttcolr.c (tt_face_load_colr): If the version is determined to be 1, then the table size has to be at least the size of the v1 header. Also, for peeking the number of base glyphs and entries in the layer list, ensure that the table is sufficiently long. Fixes #1179. Original patch by Sergey Temnikov.
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diff --git a/src/sfnt/ttcolr.c b/src/sfnt/ttcolr.c
index b432161..5df31b9 100644
--- a/src/sfnt/ttcolr.c
+++ b/src/sfnt/ttcolr.c
@@ -57,7 +57,11 @@
#define LAYER_V1_LIST_NUM_LAYERS_SIZE 4U
#define COLOR_STOP_SIZE 6U
#define LAYER_SIZE 4U
-#define COLR_HEADER_SIZE 14U
+/* https://docs.microsoft.com/en-us/typography/opentype/spec/colr#colr-header */
+/* 3 * uint16 + 2 * Offset32 */
+#define COLRV0_HEADER_SIZE 14U
+/* COLRV0_HEADER_SIZE + 5 * Offset32 */
+#define COLRV1_HEADER_SIZE 34U
#define VARIABLE_COLRV1_ENABLED \
@@ -191,7 +195,7 @@
colr_offset_in_stream = FT_STREAM_POS();
#endif
- if ( table_size < COLR_HEADER_SIZE )
+ if ( table_size < COLRV0_HEADER_SIZE )
goto InvalidTable;
if ( FT_FRAME_EXTRACT( table_size, table ) )
@@ -225,9 +229,12 @@
if ( colr->version == 1 )
{
+ if ( table_size < COLRV1_HEADER_SIZE )
+ goto InvalidTable;
+
base_glyphs_offset_v1 = FT_NEXT_ULONG( p );
- if ( base_glyphs_offset_v1 >= table_size )
+ if ( base_glyphs_offset_v1 + 4 >= table_size )
goto InvalidTable;
p1 = (FT_Byte*)( table + base_glyphs_offset_v1 );
@@ -247,6 +254,9 @@
if ( layer_offset_v1 )
{
+ if ( layer_offset_v1 + 4 >= table_size )
+ goto InvalidTable;
+
p1 = (FT_Byte*)( table + layer_offset_v1 );
num_layers_v1 = FT_PEEK_ULONG( p1 );