pgsql: adminpack: Revoke EXECUTE on pg_logfile_rotate()

adminpack: Revoke EXECUTE on pg_logfile_rotate()

In 9.6, we moved a number of functions over to using the GRANT system to
control access instead of having hard-coded superuser checks.

As it turns out, adminpack was creating another function in the catalog
for one of those backend functions where the superuser check was
removed, specifically pg_rotate_logfile(), but it didn't get the memo
about having to REVOKE EXECUTE on the alternative-name function
(pg_logfile_rotate()), meaning that in any installations with adminpack
on 9.6 and higher, any user is able to run the pg_logfile_rotate()
function, which then calls pg_rotate_logfile() and rotates the logfile.

Fix by adding a new version of adminpack (1.1) which handles the REVOKE.
As this function should have only been available to the superuser, this
is a security issue, albeit a minor one.

Security: CVE-2018-1115

Branch
------
REL9_6_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/53b79ab4fe722b1030b7e9a1580b283fca956e30

Modified Files
--------------
contrib/adminpack/Makefile | 2 +-
contrib/adminpack/adminpack--1.0--1.1.sql | 6 ++++
contrib/adminpack/adminpack--1.1.sql | 55 +++++++++++++++++++++++++++++++
contrib/adminpack/adminpack.control | 2 +-
4 files changed, 63 insertions(+), 2 deletions(-)