Commit 649ca5562d321f1008087eb0f2be584a495fabd9
2015-10-21T07:01:45
[type42] Better check invalid `sfnts' array data (#46255). * src/type42/t42parse.c (t42_parse_sfnts): Table lengths must be checked individually against available data size.
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diff --git a/ChangeLog b/ChangeLog
index b95f65e..0d52a85 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2015-10-21 Werner Lemberg <wl@gnu.org>
+
+ [type42] Better check invalid `sfnts' array data (#46255).
+
+ * src/type42/t42parse.c (t42_parse_sfnts): Table lengths must be
+ checked individually against available data size.
+
2015-10-20 Werner Lemberg <wl@gnu.org>
[cid] Add a bunch of safety checks.
diff --git a/src/type42/t42parse.c b/src/type42/t42parse.c
index a32d496..3bcf97e 100644
--- a/src/type42/t42parse.c
+++ b/src/type42/t42parse.c
@@ -575,6 +575,9 @@
while ( parser->root.cursor < limit )
{
+ FT_ULong size;
+
+
cur = parser->root.cursor;
if ( *cur == ']' )
@@ -666,6 +669,11 @@
goto Fail;
}
+ /* The whole TTF is now loaded into `string_buf'. We are */
+ /* checking its contents while copying it to `ttf_data'. */
+
+ size = limit - parser->root.cursor;
+
for ( n = 0; n < string_size; n++ )
{
switch ( status )
@@ -683,7 +691,7 @@
status = BEFORE_TABLE_DIR;
face->ttf_size = 12 + 16 * num_tables;
- if ( (FT_Long)( limit - parser->root.cursor ) < face->ttf_size )
+ if ( (FT_Long)size < face->ttf_size )
{
FT_ERROR(( "t42_parse_sfnts: invalid data in sfnts array\n" ));
error = FT_THROW( Invalid_File_Format );
@@ -714,6 +722,14 @@
len = FT_PEEK_ULONG( p );
+ if ( len > size ||
+ face->ttf_size > (FT_Long)( size - len ) )
+ {
+ FT_ERROR(( "t42_parse_sfnts:"
+ " invalid data in sfnts array\n" ));
+ error = FT_THROW( Invalid_File_Format );
+ goto Fail;
+ }
/* Pad to a 4-byte boundary length */
face->ttf_size += (FT_Long)( ( len + 3 ) & ~3U );
@@ -721,7 +737,6 @@
status = OTHER_TABLES;
- /* there are no more than 256 tables, so no size check here */
if ( FT_REALLOC( face->ttf_data, 12 + 16 * num_tables,
face->ttf_size + 1 ) )
goto Fail;