[sfnt] Additional guards on the POST table. Fixes timeout (#1055) analyzed by Ben Wagner, reported as https://crbug.com/1194092 * src/sfnt/ttload.c (tt_face_load_post): Check POST format. * src/sfnt/sfobjs.c (sfnt_load_face): Synthesize the missing unicode charmap only if the glyph names exist. * src/psnames/psmodule.c (ps_unicode_value): Short cut ".notdef" and ".null".
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diff --git a/ChangeLog b/ChangeLog
index 2fdcce5..5a6132e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2021-05-16 Alexei Podtelezhnikov <apodtele@gmail.com>
+
+ [sfnt] Additional guards on the POST table.
+
+ Fixes timeout (#1055) analyzed by Ben Wagner, reported as
+
+ https://crbug.com/1194092
+
+ * src/sfnt/ttload.c (tt_face_load_post): Check POST format.
+ * src/sfnt/sfobjs.c (sfnt_load_face): Synthesize the missing unicode
+ charmap only if the glyph names exist.
+ * src/psnames/psmodule.c (ps_unicode_value): Short cut ".notdef" and
+ ".null".
+
2021-05-13 Daniel McArdle <dmcardle@chromium.org>
[psaux] Use doubling allocation strategy for CF2_ArrStack.
diff --git a/src/psnames/psmodule.c b/src/psnames/psmodule.c
index 411b2e3..186e8ed 100644
--- a/src/psnames/psmodule.c
+++ b/src/psnames/psmodule.c
@@ -155,25 +155,24 @@
/* Look for a non-initial dot in the glyph name in order to */
/* find variants like `A.swash', `e.final', etc. */
{
- const char* p = glyph_name;
- const char* dot = NULL;
+ FT_UInt32 value = 0;
+ const char* p = glyph_name;
+
+ for ( ; *p && *p != '.'; p++ )
+ ;
- for ( ; *p; p++ )
+ /* now look up the glyph in the Adobe Glyph List; */
+ /* `.notdef', `.null' and the empty name are short cut */
+ if ( p > glyph_name )
{
- if ( *p == '.' && p > glyph_name )
- {
- dot = p;
- break;
- }
+ value = (FT_UInt32)ft_get_adobe_glyph_index( glyph_name, p );
+
+ if ( *p == '.' )
+ value |= (FT_UInt32)VARIANT_BIT;
}
- /* now look up the glyph in the Adobe Glyph List */
- if ( !dot )
- return (FT_UInt32)ft_get_adobe_glyph_index( glyph_name, p );
- else
- return (FT_UInt32)( ft_get_adobe_glyph_index( glyph_name, dot ) |
- VARIANT_BIT );
+ return value;
}
}
diff --git a/src/sfnt/sfobjs.c b/src/sfnt/sfobjs.c
index 4b7cdd2..cf73071 100644
--- a/src/sfnt/sfobjs.c
+++ b/src/sfnt/sfobjs.c
@@ -1150,9 +1150,10 @@
}
/* synthesize Unicode charmap if one is missing */
- if ( !has_unicode )
+ if ( !has_unicode &&
+ root->face_flags & FT_FACE_FLAG_GLYPH_NAMES )
{
- FT_CharMapRec cmaprec;
+ FT_CharMapRec cmaprec;
cmaprec.face = root;
diff --git a/src/sfnt/ttload.c b/src/sfnt/ttload.c
index ec66edc..d8ea9ea 100644
--- a/src/sfnt/ttload.c
+++ b/src/sfnt/ttload.c
@@ -1312,6 +1312,12 @@
if ( FT_STREAM_READ_FIELDS( post_fields, post ) )
return error;
+ if ( post->FormatType != 0x00030000L &&
+ post->FormatType != 0x00025000L &&
+ post->FormatType != 0x00020000L &&
+ post->FormatType != 0x00010000L )
+ return FT_THROW( Invalid_Post_Table_Format );
+
/* we don't load the glyph names, we do that in another */
/* module (ttpost). */