The recent commit to fix a gzip header extra field processing bug
introduced the new bug fixed here.
(cherry picked from zlib commit 1eb7682f845ac9e9bf9ae35bbfb3bad5dacbd91d)
If the extra field was larger than the space the user provided with
inflateGetHeader(), and if multiple calls of inflate() delivered
the extra header data, then there could be a buffer overflow of the
provided space. This commit assures that provided space is not
exceeded.
(cherry picked from zlib commit eff308af425b67093bab25f80f1ae950166bece1)
This is a prerequisite of unifying kernel zlib instances.
Submitted by: Yoshihiro Ota <ota at j.email.ne.jp>
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D20191