Commit e9f0cdb6c0f44edcebc3ceb9d102f48f4aebd055
2010-06-27T12:34:19
[cff] Protect against invalid `hintmask' and `cntrmask' operators. * src/cff/cffgload.c (cff_decoder_parse_charstrings) <cff_op_hintmask>: Ensure that we don't exceed `limit' while parsing the bit masks of the `hintmask' and `cntrmask' operators.
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diff --git a/ChangeLog b/ChangeLog
index c01ecb8..63dc3f3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2010-06-27 Werner Lemberg <wl@gnu.org>
+
+ [cff] Protect against invalid `hintmask' and `cntrmask' operators.
+
+ * src/cff/cffgload.c (cff_decoder_parse_charstrings)
+ <cff_op_hintmask>: Ensure that we don't exceed `limit' while parsing
+ the bit masks of the `hintmask' and `cntrmask' operators.
+
2010-06-26 Werner Lemberg <wl@gnu.org>
Fix PFR change 2010-06-24.
diff --git a/src/cff/cffgload.c b/src/cff/cffgload.c
index 6719018..51efcb9 100644
--- a/src/cff/cffgload.c
+++ b/src/cff/cffgload.c
@@ -1341,6 +1341,14 @@
if ( hinter )
{
+ /* In a valid charstring there must be at least three bytes */
+ /* after `hintmask' or `cntrmask' (two for a `moveto' */
+ /* operator and one for `endchar'). Additionally, there */
+ /* must be space for `num_hints' bits. */
+
+ if ( ( ip + 3 + ( decoder->num_hints >> 8 ) ) >= limit )
+ goto Syntax_Error;
+
if ( op == cff_op_hintmask )
hinter->hintmask( hinter->hints,
builder->current->n_points,
@@ -1360,7 +1368,7 @@
FT_TRACE4(( " (maskbytes:" ));
for ( maskbyte = 0;
- maskbyte < (FT_UInt)(( decoder->num_hints + 7 ) >> 3);
+ maskbyte < (FT_UInt)( ( decoder->num_hints + 7 ) >> 3 );
maskbyte++, ip++ )
FT_TRACE4(( " 0x%02X", *ip ));