ref: 3915a18b8c0f4e2090bf9496a49c38986ab18d70
parent: 2c8e6279a7bfc314f3934bc8d126ecb1e5e284f1
author: Werner Lemberg <[email protected]>
date: Wed Aug 29 02:53:54 EDT 2018
[cff] Fix handling of `roll' op in old engine. Reported as https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=10080 * src/psaux/cffdecode.c (cff_decoder_parse_charstrings) <cff_op_roll> [CFF_CONFIG_OPTION_OLD_ENGINE]: Use modulo for loop count, as documented in the specification.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2018-08-29 Werner Lemberg <[email protected]>
+
+ [cff] Fix handling of `roll' op in old engine.
+
+ Reported as
+
+ https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=10080
+
+ * src/psaux/cffdecode.c (cff_decoder_parse_charstrings) <cff_op_roll>
+ [CFF_CONFIG_OPTION_OLD_ENGINE]: Use modulo for loop count, as
+ documented in the specification.
+
2018-08-26 Werner Lemberg <[email protected]>
* src/truetype/ttobjs.c (tt_size_read_bytecode): Trace CVT values.
--- a/src/psaux/cffdecode.c
+++ b/src/psaux/cffdecode.c
@@ -1821,6 +1821,7 @@
if ( idx >= 0 )
{+ idx = idx % count;
while ( idx > 0 )
{FT_Fixed tmp = args[count - 1];
@@ -1835,6 +1836,10 @@
}
else
{+ /* before C99 it is implementation-defined whether */
+ /* the result of `%' is negative if the first operand */
+ /* is negative */
+ idx = -( ( -idx ) % count );
while ( idx < 0 )
{FT_Fixed tmp = args[0];
--- a/src/psaux/psstack.c
+++ b/src/psaux/psstack.c
@@ -258,6 +258,9 @@
return;
}
+ /* before C99 it is implementation-defined whether */
+ /* the result of `%' is negative if the first operand */
+ /* is negative */
if ( shift < 0 )
shift = -( ( -shift ) % count );
else