Fix validation for various cmap table formats.

* src/sfnt/ttcmap.c (tt_cmap8_validate, tt_cmap10_validate,
tt_cmap12_validate): Check `length' correctly.
(tt_cmap_14_validate): Check `length' and `numMappings' correctly.
This commit is contained in:
Werner Lemberg 2009-03-20 08:03:58 +01:00
parent a49db4f866
commit a18788b14d
2 changed files with 17 additions and 5 deletions

View File

@ -1,3 +1,12 @@
2009-03-20 Werner Lemberg <wl@gnu.org>
Tavis Ormandy <taviso@google.com>
Fix validation for various cmap table formats.
* src/sfnt/ttcmap.c (tt_cmap8_validate, tt_cmap10_validate,
tt_cmap12_validate): Check `length' correctly.
(tt_cmap_14_validate): Check `length' and `numMappings' correctly.
2009-03-20 Werner Lemberg <wl@gnu.org>
Protect against malformed compressed data.

View File

@ -1635,7 +1635,7 @@
FT_INVALID_TOO_SHORT;
length = TT_NEXT_ULONG( p );
if ( table + length > valid->limit || length < 8208 )
if ( length > (FT_UInt32)( valid->limit - table ) || length < 8192 + 16 )
FT_INVALID_TOO_SHORT;
is32 = table + 12;
@ -1863,7 +1863,8 @@
p = table + 16;
count = TT_NEXT_ULONG( p );
if ( table + length > valid->limit || length < 20 + count * 2 )
if ( length > (FT_ULong)( valid->limit - table ) ||
length < 20 + count * 2 )
FT_INVALID_TOO_SHORT;
/* check glyph indices */
@ -2048,7 +2049,8 @@
p = table + 12;
num_groups = TT_NEXT_ULONG( p );
if ( table + length > valid->limit || length < 16 + 12 * num_groups )
if ( length > (FT_ULong)( valid->limit - table ) ||
length < 16 + 12 * num_groups )
FT_INVALID_TOO_SHORT;
/* check groups, they must be in increasing order */
@ -2429,7 +2431,8 @@
FT_ULong num_selectors = TT_NEXT_ULONG( p );
if ( table + length > valid->limit || length < 10 + 11 * num_selectors )
if ( length > (FT_ULong)( valid->limit - table ) ||
length < 10 + 11 * num_selectors )
FT_INVALID_TOO_SHORT;
/* check selectors, they must be in increasing order */
@ -2491,7 +2494,7 @@
FT_ULong i, lastUni = 0;
if ( ndp + numMappings * 4 > valid->limit )
if ( numMappings * 4 > (FT_ULong)( valid->limit - ndp ) )
FT_INVALID_TOO_SHORT;
for ( i = 0; i < numMappings; ++i )