Thread: [COMMITTERS] pgsql: Again match pg_user_mappings toinformation_schema.user_mapping_

Again match pg_user_mappings to information_schema.user_mapping_options.

Commit 3eefc51053f250837c3115c12f8119d16881a2d7 claimed to make
pg_user_mappings enforce the qualifications user_mapping_options had
been enforcing, but its removal of a longstanding restriction left them
distinct when the current user is the subject of a mapping yet has no
server privileges.  user_mapping_options emits no rows for such a
mapping, but pg_user_mappings includes full umoptions.  Change
pg_user_mappings to show null for umoptions.  Back-patch to 9.2, like
the above commit.

Reviewed by Tom Lane.  Reported by Jeff Janes.

Security: CVE-2017-7547

Branch
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REL9_3_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5e8e009146e3cae5c596d6e857a9c98fe22657b8

Modified Files
--------------
doc/src/sgml/catalogs.sgml                 |   32 +-
src/backend/catalog/system_views.sql       |    4 +-
src/test/regress/expected/foreign_data.out |   32 +-
src/test/regress/expected/rules.out        | 1600 ++++++++++++++--------------
src/test/regress/sql/foreign_data.sql      |   17 +-
5 files changed, 856 insertions(+), 829 deletions(-)