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From 602040b1112c9f94d68e200be59ea7ac3d104565 Mon Sep 17 00:00:00 2001
From: Werner Lemberg <wl@gnu.org>
Date: Wed, 12 Nov 2014 19:51:20 +0000
Subject: [sfnt] Fix Savannah bug #43588.
* src/sfnt/ttcmap.c (tt_cmap8_validate, tt_cmap10_validate,
tt_cmap12_validate, tt_cmap13_validate, tt_cmap14_validate): Protect
against overflow in additions and multiplications.
---
diff --git a/src/sfnt/ttcmap.c b/src/sfnt/ttcmap.c
index f9acf5d..712bd4f 100644
--- a/src/sfnt/ttcmap.c
+++ b/src/sfnt/ttcmap.c
@@ -1647,7 +1647,8 @@
p = is32 + 8192; /* skip `is32' array */
num_groups = TT_NEXT_ULONG( p );
- if ( p + num_groups * 12 > valid->limit )
+ /* p + num_groups * 12 > valid->limit ? */
+ if ( num_groups > (FT_UInt32)( valid->limit - p ) / 12 )
FT_INVALID_TOO_SHORT;
/* check groups, they must be in increasing order */
@@ -1672,7 +1673,12 @@
if ( valid->level >= FT_VALIDATE_TIGHT )
{
- if ( start_id + end - start >= TT_VALID_GLYPH_COUNT( valid ) )
+ FT_UInt32 d = end - start;
+
+
+ /* start_id + end - start >= TT_VALID_GLYPH_COUNT( valid ) ? */
+ if ( d > TT_VALID_GLYPH_COUNT( valid ) ||
+ start_id >= TT_VALID_GLYPH_COUNT( valid ) - d )
FT_INVALID_GLYPH_ID;
count = (FT_UInt32)( end - start + 1 );
@@ -1870,7 +1876,9 @@
count = TT_NEXT_ULONG( p );
if ( length > (FT_ULong)( valid->limit - table ) ||
- length < 20 + count * 2 )
+ /* length < 20 + count * 2 ? */
+ length < 20 ||
+ ( length - 20 ) / 2 < count )
FT_INVALID_TOO_SHORT;
/* check glyph indices */
@@ -2057,7 +2065,9 @@
num_groups = TT_NEXT_ULONG( p );
if ( length > (FT_ULong)( valid->limit - table ) ||
- length < 16 + 12 * num_groups )
+ /* length < 16 + 12 * num_groups ? */
+ length < 16 ||
+ ( length - 16 ) / 12 < num_groups )
FT_INVALID_TOO_SHORT;
/* check groups, they must be in increasing order */
@@ -2079,7 +2089,12 @@
if ( valid->level >= FT_VALIDATE_TIGHT )
{
- if ( start_id + end - start >= TT_VALID_GLYPH_COUNT( valid ) )
+ FT_UInt32 d = end - start;
+
+
+ /* start_id + end - start >= TT_VALID_GLYPH_COUNT( valid ) ? */
+ if ( d > TT_VALID_GLYPH_COUNT( valid ) ||
+ start_id >= TT_VALID_GLYPH_COUNT( valid ) - d )
FT_INVALID_GLYPH_ID;
}
@@ -2381,7 +2396,9 @@
num_groups = TT_NEXT_ULONG( p );
if ( length > (FT_ULong)( valid->limit - table ) ||
- length < 16 + 12 * num_groups )
+ /* length < 16 + 12 * num_groups ? */
+ length < 16 ||
+ ( length - 16 ) / 12 < num_groups )
FT_INVALID_TOO_SHORT;
/* check groups, they must be in increasing order */
@@ -2762,7 +2779,9 @@
if ( length > (FT_ULong)( valid->limit - table ) ||
- length < 10 + 11 * num_selectors )
+ /* length < 10 + 11 * num_selectors ? */
+ length < 10 ||
+ ( length - 10 ) / 11 < num_selectors )
FT_INVALID_TOO_SHORT;
/* check selectors, they must be in increasing order */
@@ -2798,7 +2817,8 @@
FT_ULong lastBase = 0;
- if ( defp + numRanges * 4 > valid->limit )
+ /* defp + numRanges * 4 > valid->limit ? */
+ if ( numRanges > (FT_ULong)( valid->limit - defp ) / 4 )
FT_INVALID_TOO_SHORT;
for ( i = 0; i < numRanges; ++i )
@@ -2825,7 +2845,8 @@
FT_ULong i, lastUni = 0;
- if ( numMappings * 4 > (FT_ULong)( valid->limit - ndp ) )
+ /* numMappings * 4 > (FT_ULong)( valid->limit - ndp ) ? */
+ if ( numMappings > ( (FT_ULong)( valid->limit - ndp ) ) / 4 )
FT_INVALID_TOO_SHORT;
for ( i = 0; i < numMappings; ++i )
--
cgit v0.9.0.2
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