shithub: freetype+ttf2subf

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[woff2] Fix memory leak.

Reported as

  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28148

* src/sfnt/sfwoff2.c (woff2_open_font): Reject fonts that have
multiple tables with the same tag.  While not explicitly forbidden
in the OpenType specification, it is implicitly forbidden by
describing a binary search algorithm for tables that only works
reliably if table tags are unique.

git/fs: mount .git/fs: mount/attach disallowed

--- a/ChangeLog

+++ b/ChangeLog

@@ -1,3 +1,17 @@

+2021-02-25  Werner Lemberg  <wl@gnu.org>

+

+	[woff2] Fix memory leak.

+

+	Reported as

+

+	  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28148

+

+	* src/sfnt/sfwoff2.c (woff2_open_font): Reject fonts that have

+	multiple tables with the same tag.  While not explicitly forbidden

+	in the OpenType specification, it is implicitly forbidden by

+	describing a binary search algorithm for tables that only works

+	reliably if table tags are unique.

+

 2021-02-22  Werner Lemberg  <wl@gnu.org>

 	* CMakeLists.txt: Update location of `LICENSE.TXT`.

--- a/src/sfnt/sfwoff2.c

+++ b/src/sfnt/sfwoff2.c

@@ -2208,6 +2208,25 @@

               sizeof ( WOFF2_Table ),

               compare_tags );

+    /* reject fonts that have multiple tables with the same tag */

+    for ( nn = 1; nn < woff2.num_tables; nn++ )

+    {

+      FT_ULong  tag = indices[nn]->Tag;

+

+

+      if ( tag == indices[nn - 1]->Tag )

+      {

+        FT_ERROR(( "woff2_open_font:"

+                   " multiple tables with tag `%c%c%c%c'.\n",

+                   (FT_Char)( tag >> 24 ),

+                   (FT_Char)( tag >> 16 ),

+                   (FT_Char)( tag >> 8  ),

+                   (FT_Char)( tag       ) ));

+        error = FT_THROW( Invalid_Table );

+        goto Exit;

+      }

+    }

+

     if ( woff2.uncompressed_size < 1 )

     {

       error = FT_THROW( Invalid_Table );