[Git][freetype/freetype][master] [cff, truetype] Validate variation axes immediately.

[Alexei Podtelezhnikov (@apodtele)]

Alexei Podtelezhnikov pushed to branch master at FreeType / FreeType

Commits:

• 5f131cfd
  by Alexei Podtelezhnikov (Алексей Подтележников) at 2024-05-21T16:24:43-04:00

  [cff, truetype] Validate variation axes immediately.
  
  Instead of validating variation axes in every access, OpenType specs
  suggest that peak = 0 be used to tag invalid ranges.  This implements
  just that once during loading.
  
  * src/cff/cffload.c (cff_blend_build_vector): Move the range checks...
  (cff_vstore_load): ... here.
  * src/truetype/ttgxvar.c (tt_var_get_item_delta): Ditto...
  (tt_var_load_item_variation_store): ... ditto.
  

2 changed files:

• src/cff/cffload.c
• src/truetype/ttgxvar.c

Changes:

src/cff/cffload.c

---

...	...	@@ -1202,17 +1202,21 @@
1202	1202	{
1203	1203	CFF_AxisCoords* axis = &region->axisList[j];
1204	1204
1205		- FT_Int16 start14, peak14, end14;
	1205	+ FT_Int start, peak, end;
1206	1206
1207	1207
1208		- if ( FT_READ_SHORT( start14 ) ||
1209		- FT_READ_SHORT( peak14 ) ||
1210		- FT_READ_SHORT( end14 ) )
	1208	+ if ( FT_READ_SHORT( start ) ||
	1209	+ FT_READ_SHORT( peak ) ||
	1210	+ FT_READ_SHORT( end ) )
1211	1211	goto Exit;
1212	1212
1213		- axis->startCoord = FT_fdot14ToFixed( start14 );
1214		- axis->peakCoord = FT_fdot14ToFixed( peak14 );
1215		- axis->endCoord = FT_fdot14ToFixed( end14 );
	1213	+ /* immediately tag invalid ranges with special peak = 0 */
	1214	+ if ( ( start < 0 && end > 0 ) || start > peak || peak > end )
	1215	+ peak = 0;
	1216	+
	1217	+ axis->startCoord = FT_fdot14ToFixed( start );
	1218	+ axis->peakCoord = FT_fdot14ToFixed( peak );
	1219	+ axis->endCoord = FT_fdot14ToFixed( end );
1216	1220	}
1217	1221	}
1218	1222
...	...	@@ -1498,19 +1502,11 @@
1498	1502
1499	1503
1500	1504	/* compute the scalar contribution of this axis */
1501		- /* while running mandatory range checks */
	1505	+ /* with peak of 0 used for invalid axes */
1502	1506	if ( axis->peakCoord == NDV[j] ||
1503	1507	axis->peakCoord == 0 )
1504	1508	continue;
1505	1509
1506		- else if ( axis->startCoord < 0 &&
1507		- axis->endCoord > 0 )
1508		- continue;
1509		-
1510		- else if ( axis->startCoord > axis->peakCoord ||
1511		- axis->peakCoord > axis->endCoord )
1512		- continue;
1513		-
1514	1510	/* ignore this region if coords are out of range */
1515	1511	else if ( NDV[j] <= axis->startCoord ||
1516	1512	NDV[j] >= axis->endCoord )

src/truetype/ttgxvar.c

---

...	...	@@ -596,7 +596,7 @@
596	596
597	597	for ( j = 0; j < itemStore->axisCount; j++ )
598	598	{
599		- FT_Short start, peak, end;
	599	+ FT_Int start, peak, end;
600	600
601	601
602	602	if ( FT_READ_SHORT( start ) ||
...	...	@@ -604,6 +604,10 @@
604	604	FT_READ_SHORT( end ) )
605	605	goto Exit;
606	606
	607	+ /* immediately tag invalid ranges with special peak = 0 */
	608	+ if ( ( start < 0 && end > 0 ) || start > peak || peak > end )
	609	+ peak = 0;
	610	+
607	611	axisCoords[j].startCoord = FT_fdot14ToFixed( start );
608	612	axisCoords[j].peakCoord = FT_fdot14ToFixed( peak );
609	613	axisCoords[j].endCoord = FT_fdot14ToFixed( end );
...	...	@@ -1078,19 +1082,11 @@
1078	1082
1079	1083
1080	1084	/* compute the scalar contribution of this axis */
1081		- /* while running mandatory range checks */
	1085	+ /* with peak of 0 used for invalid axes */
1082	1086	if ( axis->peakCoord == ncv ||
1083	1087	axis->peakCoord == 0 )
1084	1088	continue;
1085	1089
1086		- else if ( axis->startCoord < 0 &&
1087		- axis->endCoord > 0 )
1088		- continue;
1089		-
1090		- else if ( axis->startCoord > axis->peakCoord ||
1091		- axis->peakCoord > axis->endCoord )
1092		- continue;
1093		-
1094	1090	/* ignore this region if coords are out of range */
1095	1091	else if ( ncv <= axis->startCoord ||
1096	1092	ncv >= axis->endCoord )

—
View it on GitLab.
You're receiving this email because of your account on gitlab.freedesktop.org. Manage all notifications · Help