Add security checks to selectivity estimation functions
Some selectivity estimation functions run user-supplied operators over
data obtained from pg_statistic without security checks, which allows
those operators to leak pg_statistic data without having privileges on
the underlying tables. Fix by checking that one of the following is
satisfied: (1) the user has table or column privileges on the table
underlying the pg_statistic data, or (2) the function implementing the
user-supplied operator is leak-proof. If neither is satisfied, planning
will proceed as if there are no statistics available.
At least one of these is satisfied in most cases in practice. The only
situations that are negatively impacted are user-defined or
not-leak-proof operators on a security-barrier view.
Reported-by: Robert Haas <robertmhaas@gmail.com>
Author: Peter Eisentraut <peter_e@gmx.net>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Security: CVE-2017-7484
Branch
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REL9_3_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/4f1b2089a1b8f82cbd28b4cd8d0e1e9f1486d2b6
Modified Files
--------------
doc/src/sgml/planstats.sgml | 60 +++++++++++
src/backend/utils/adt/array_selfuncs.c | 6 +-
src/backend/utils/adt/rangetypes_selfuncs.c | 22 ++++
src/backend/utils/adt/selfuncs.c | 160 ++++++++++++++++++++++------
src/include/utils/selfuncs.h | 2 +
src/test/regress/expected/privileges.out | 97 +++++++++++++++++
src/test/regress/sql/privileges.sql | 61 +++++++++++
7 files changed, 376 insertions(+), 32 deletions(-)