imp 06a9c917f2 Fix pointer arithmetic
Pointer math to find the size in bytes only works with char types.
Use correct pointer math to determine if we have enough of a header to
look at or not.

MFC After: 3 days
X-MFX-With: r339800
Noticed by: jhb@
Sponsored by: Netflix, Inc
2018-10-26 23:44:50 +00:00
..
2018-10-26 23:44:50 +00:00