diff --git a/ChangeLog b/ChangeLog index 0aa2a2b99..80a485588 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,20 @@ +2018-08-26 Werner Lemberg + + [truetype] Avoid nested frames. + + Triggered by + + https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=10054 + + * src/truetype/ttgload.c (load_truetype_glyph): Don't use variable + `opened_frame' to trace whether a frame must be closed at the end of + function: This fails because `TT_Vary_Apply_Glyph_Deltas' (which + gets called for space glyphs) uses a frame by itself. Instead, + close the frame after loading the header, then use another frame for + the remaining part of the glyph later on. + + Also avoid calling `tt_get_metrics' twice under some circumstances. + 2018-08-26 Werner Lemberg Various minor clean-ups. diff --git a/src/truetype/ttgload.c b/src/truetype/ttgload.c index d76758465..b59e978cf 100644 --- a/src/truetype/ttgload.c +++ b/src/truetype/ttgload.c @@ -1534,12 +1534,11 @@ FT_UInt recurse_count, FT_Bool header_only ) { - FT_Error error = FT_Err_Ok; + FT_Error error = FT_Err_Ok; FT_Fixed x_scale, y_scale; FT_ULong offset; - TT_Face face = loader->face; - FT_GlyphLoader gloader = loader->gloader; - FT_Bool opened_frame = 0; + TT_Face face = loader->face; + FT_GlyphLoader gloader = loader->gloader; #ifdef FT_CONFIG_OPTION_INCREMENTAL FT_StreamRec inc_stream; @@ -1572,15 +1571,15 @@ loader->glyph_index = glyph_index; - if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 ) + if ( loader->load_flags & FT_LOAD_NO_SCALE ) { - x_scale = loader->size->metrics->x_scale; - y_scale = loader->size->metrics->y_scale; + x_scale = 0x10000L; + y_scale = 0x10000L; } else { - x_scale = 0x10000L; - y_scale = 0x10000L; + x_scale = loader->size->metrics->x_scale; + y_scale = loader->size->metrics->y_scale; } /* Set `offset' to the start of the glyph relative to the start of */ @@ -1639,38 +1638,36 @@ if ( error ) goto Exit; - opened_frame = 1; - /* read glyph header first */ error = face->read_glyph_header( loader ); - if ( error ) - goto Exit; - /* the metrics must be computed after loading the glyph header */ - /* since we need the glyph's `yMax' value in case the vertical */ - /* metrics must be emulated */ - error = tt_get_metrics( loader, glyph_index ); - if ( error ) - goto Exit; + face->forget_glyph_frame( loader ); - if ( header_only ) + if ( error ) goto Exit; } + /* a space glyph */ if ( loader->byte_len == 0 || loader->n_contours == 0 ) { loader->bbox.xMin = 0; loader->bbox.xMax = 0; loader->bbox.yMin = 0; loader->bbox.yMax = 0; + } - error = tt_get_metrics( loader, glyph_index ); - if ( error ) - goto Exit; + /* the metrics must be computed after loading the glyph header */ + /* since we need the glyph's `yMax' value in case the vertical */ + /* metrics must be emulated */ + error = tt_get_metrics( loader, glyph_index ); + if ( error ) + goto Exit; - if ( header_only ) - goto Exit; + if ( header_only ) + goto Exit; + if ( loader->byte_len == 0 || loader->n_contours == 0 ) + { /* must initialize points before (possibly) overriding */ /* glyph metrics from the incremental interface */ tt_loader_set_pp( loader ); @@ -1726,7 +1723,6 @@ loader->pp4.x = points[3].x; loader->pp4.y = points[3].y; - /* recalculate linear horizontal and vertical advances */ /* if we don't have HVAR and VVAR, respectively */ if ( !( loader->face->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) ) @@ -1767,6 +1763,14 @@ /***********************************************************************/ /***********************************************************************/ + /* we now open a frame again, right after the glyph header */ + /* (which consists of 10 bytes) */ + error = face->access_glyph_frame( loader, glyph_index, + face->glyf_offset + offset + 10, + (FT_UInt)loader->byte_len - 10 ); + if ( error ) + goto Exit; + /* if it is a simple glyph, load it */ if ( loader->n_contours > 0 ) @@ -1777,7 +1781,6 @@ /* all data have been read */ face->forget_glyph_frame( loader ); - opened_frame = 0; error = TT_Process_Simple_Glyph( loader ); if ( error ) @@ -1812,7 +1815,6 @@ * pointers with a width of at least 32 bits. */ - /* clear the nodes filled by sibling chains */ node = ft_list_get_node_at( &loader->composites, recurse_count ); for ( node2 = node; node2; node2 = node2->next ) @@ -1852,7 +1854,6 @@ /* all data we need are read */ face->forget_glyph_frame( loader ); - opened_frame = 0; #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT @@ -2107,9 +2108,6 @@ Exit: - if ( opened_frame ) - face->forget_glyph_frame( loader ); - #ifdef FT_CONFIG_OPTION_INCREMENTAL if ( glyph_data_loaded )