* src/sfnt/sfwoff2.c (woff2_open_font): Add sanity check.

Don't trust `totalSfntSize' unconditionally.

Reported as

  https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=16893
This commit is contained in:
Werner Lemberg 2019-09-01 23:03:09 +02:00
parent cbee985a2b
commit 543a3b939d
2 changed files with 26 additions and 1 deletions

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@ -1,3 +1,13 @@
2019-09-01 Werner Lemberg <wl@gnu.org>
* src/sfnt/sfwoff2.c (woff2_open_font): Add sanity check.
Don't trust `totalSfntSize' unconditionally.
Reported as
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=16893
2019-08-27 Dominik Röttsches <drott@chromium.org>
[woff2] Don't use `FT_UInt64' (#56815).

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@ -2092,7 +2092,22 @@
/* This is what we normally expect. */
/* Initially trust `totalSfntSize' and change later as required. */
if ( woff2.totalSfntSize > sfnt_size )
sfnt_size = woff2.totalSfntSize;
{
/* However, adjust the value to something reasonable. */
/* Factor 64 is heuristic. */
if ( ( woff2.totalSfntSize >> 6 ) > sfnt_size )
sfnt_size <<= 6;
else
sfnt_size = woff2.totalSfntSize;
/* Value 1<<26 = 67108864 is heuristic. */
if (sfnt_size >= (1 << 26))
sfnt_size = 1 << 26;
FT_TRACE4(( "adjusting estimate of uncompressed font size to %lu\n",
sfnt_size ));
}
/* Write sfnt header. */
if ( FT_ALLOC( sfnt, sfnt_size ) ||