ref: 8c8f51c55813b4f01e1a77d4fc8838c6a5fb998c
parent: 9079c5d91aa87bcae223fc933b9c0ebf346b7d64
author: Werner Lemberg <wl@gnu.org>
date: Fri Nov 19 16:50:22 EST 2021
Avoid undefined left-shifts. We really have to use double casts to avoid issues with C's and C++'s signedness propagation rules in implicit casts. Reported as https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=41178 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=41182 * include/freetype/config/public-macros.h (FT_STATIC_CAST, FT_REINTERPRET_CAST): Modify macro to take two arguments. Update all callers. (FT_STATIC_BYTE_CAST): New macro. * include/freetype/freetype.h (FT_ENC_TAG): Use `FT_STATIC_BYTE_CAST`. * include/freetype/ftimage.h (FT_IMAGE_TAG): Ditto. * include/freetype/fttypes.h (FT_MAKE_TAG): Ditto. Use `FT_Tag` for casting. * src/ftraster/ftmisc.h (FT_MAKE_TAG): Removed, no longer needed. (FT_STATIC_BYTE_CAST): New macro. * src/smooth/ftgrays.c (FT_STATIC_CAST): Replace with... (FT_STATIC_BYTE_CAST): ... this.
--- a/include/freetype/config/public-macros.h
+++ b/include/freetype/config/public-macros.h
@@ -120,11 +120,16 @@
* Support for casts in both C and C++.
*/
#ifdef __cplusplus
-#define FT_STATIC_CAST( type ) static_cast<type>
-#define FT_REINTERPRET_CAST( type ) reinterpret_cast<type>
+#define FT_STATIC_CAST( type, var ) static_cast<type>(var)
+#define FT_REINTERPRET_CAST( type, var ) reinterpret_cast<type>(var)
+
+#define FT_STATIC_BYTE_CAST( type, var ) \
+ static_cast<type>( static_cast<unsigned char>( var ) )
#else
-#define FT_STATIC_CAST( type ) (type)
-#define FT_REINTERPRET_CAST( type ) (type)
+#define FT_STATIC_CAST( type, var ) (type)(var)
+#define FT_REINTERPRET_CAST( type, var ) (type)(var)
+
+#define FT_STATIC_BYTE_CAST( type, var ) (type)(unsigned char)(var)
#endif
--- a/include/freetype/freetype.h
+++ b/include/freetype/freetype.h
@@ -617,11 +617,11 @@
#ifndef FT_ENC_TAG
-#define FT_ENC_TAG( value, a, b, c, d ) \
- value = ( ( FT_STATIC_CAST( FT_Byte )(a) << 24 ) | \
- ( FT_STATIC_CAST( FT_Byte )(b) << 16 ) | \
- ( FT_STATIC_CAST( FT_Byte )(c) << 8 ) | \
- FT_STATIC_CAST( FT_Byte )(d) )
+#define FT_ENC_TAG( value, a, b, c, d ) \
+ value = ( ( FT_STATIC_BYTE_CAST( FT_UInt32, a ) << 24 ) | \
+ ( FT_STATIC_BYTE_CAST( FT_UInt32, b ) << 16 ) | \
+ ( FT_STATIC_BYTE_CAST( FT_UInt32, c ) << 8 ) | \
+ FT_STATIC_BYTE_CAST( FT_UInt32, d ) )
#endif /* FT_ENC_TAG */
@@ -3182,7 +3182,7 @@
* necessary to empty the cache after a mode switch to avoid false hits.
*
*/
-#define FT_LOAD_TARGET_( x ) ( FT_STATIC_CAST( FT_Int32 )( (x) & 15 ) << 16 )
+#define FT_LOAD_TARGET_( x ) ( FT_STATIC_CAST( FT_Int32, (x) & 15 ) << 16 )
#define FT_LOAD_TARGET_NORMAL FT_LOAD_TARGET_( FT_RENDER_MODE_NORMAL )
#define FT_LOAD_TARGET_LIGHT FT_LOAD_TARGET_( FT_RENDER_MODE_LIGHT )
@@ -3201,8 +3201,8 @@
* @FT_LOAD_TARGET_XXX value.
*
*/
-#define FT_LOAD_TARGET_MODE( x ) \
- FT_STATIC_CAST( FT_Render_Mode )( ( (x) >> 16 ) & 15 )
+#define FT_LOAD_TARGET_MODE( x ) \
+ FT_STATIC_CAST( FT_Render_Mode, ( (x) >> 16 ) & 15 )
/**************************************************************************
--- a/include/freetype/ftimage.h
+++ b/include/freetype/ftimage.h
@@ -696,11 +696,11 @@
*/
#ifndef FT_IMAGE_TAG
-#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) \
- value = ( ( FT_STATIC_CAST( unsigned char )( _x1 ) << 24 ) | \
- ( FT_STATIC_CAST( unsigned char )( _x2 ) << 16 ) | \
- ( FT_STATIC_CAST( unsigned char )( _x3 ) << 8 ) | \
- FT_STATIC_CAST( unsigned char )( _x4 ) )
+#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) \
+ value = ( ( FT_STATIC_BYTE_CAST( unsigned long, _x1 ) << 24 ) | \
+ ( FT_STATIC_BYTE_CAST( unsigned long, _x2 ) << 16 ) | \
+ ( FT_STATIC_BYTE_CAST( unsigned long, _x3 ) << 8 ) | \
+ FT_STATIC_BYTE_CAST( unsigned long, _x4 ) )
#endif /* FT_IMAGE_TAG */
--- a/include/freetype/ftmodapi.h
+++ b/include/freetype/ftmodapi.h
@@ -347,9 +347,9 @@
* 2.11
*
*/
-#define FT_FACE_DRIVER_NAME( face ) \
- ( ( *FT_REINTERPRET_CAST( FT_Module_Class** ) \
- ( ( face )->driver ) )->module_name )
+#define FT_FACE_DRIVER_NAME( face ) \
+ ( ( *FT_REINTERPRET_CAST( FT_Module_Class**, \
+ ( face )->driver ) )->module_name )
/**************************************************************************
--- a/include/freetype/fttypes.h
+++ b/include/freetype/fttypes.h
@@ -479,18 +479,19 @@
*
* @description:
* This macro converts four-letter tags that are used to label TrueType
- * tables into an unsigned long, to be used within FreeType.
+ * tables into an `FT_Tag` type, to be used within FreeType.
*
* @note:
* The produced values **must** be 32-bit integers. Don't redefine this
* macro.
*/
-#define FT_MAKE_TAG( _x1, _x2, _x3, _x4 ) \
- FT_STATIC_CAST( FT_Tag ) \
- ( ( FT_STATIC_CAST( FT_Byte )( _x1 ) << 24 ) | \
- ( FT_STATIC_CAST( FT_Byte )( _x2 ) << 16 ) | \
- ( FT_STATIC_CAST( FT_Byte )( _x3 ) << 8 ) | \
- FT_STATIC_CAST( FT_Byte )( _x4 ) )
+#define FT_MAKE_TAG( _x1, _x2, _x3, _x4 ) \
+ FT_STATIC_CAST( \
+ FT_Tag, \
+ ( ( FT_STATIC_BYTE_CAST( FT_Tag, _x1 ) << 24 ) | \
+ ( FT_STATIC_BYTE_CAST( FT_Tag, _x2 ) << 16 ) | \
+ ( FT_STATIC_BYTE_CAST( FT_Tag, _x3 ) << 8 ) | \
+ FT_STATIC_BYTE_CAST( FT_Tag, _x4 ) ) )
/*************************************************************************/
@@ -588,7 +589,7 @@
#define FT_IS_EMPTY( list ) ( (list).head == 0 )
-#define FT_BOOL( x ) FT_STATIC_CAST( FT_Bool )( (x) != 0 )
+#define FT_BOOL( x ) FT_STATIC_CAST( FT_Bool, (x) != 0 )
/* concatenate C tokens */
#define FT_ERR_XCAT( x, y ) x ## y
--- a/src/raster/ftmisc.h
+++ b/src/raster/ftmisc.h
@@ -47,11 +47,8 @@
typedef signed long FT_F26Dot6;
typedef int FT_Error;
-#define FT_MAKE_TAG( _x1, _x2, _x3, _x4 ) \
- ( ( (FT_ULong)_x1 << 24 ) | \
- ( (FT_ULong)_x2 << 16 ) | \
- ( (FT_ULong)_x3 << 8 ) | \
- (FT_ULong)_x4 )
+
+#define FT_STATIC_BYTE_CAST( type, var ) (type)(FT_Byte)(var)
/* from include/freetype/ftsystem.h */
--- a/src/smooth/ftgrays.c
+++ b/src/smooth/ftgrays.c
@@ -152,7 +152,7 @@
#define ADD_INT( a, b ) \
(int)( (unsigned int)(a) + (unsigned int)(b) )
-#define FT_STATIC_CAST( type ) (type)
+#define FT_STATIC_BYTE_CAST( type, var ) (type)(unsigned char)(var)
#define ft_memset memset