psql: Allow pg_read_all_stats to see database size in \l+

pg_database_size() allows access to users who have either CONNECT
privilege on the target database or privileges of the pg_read_all_stats
role. However, previously, psql's \l+ checked only for CONNECT,
so users with privileges of pg_read_all_stats still saw "No Access" for
databases they could not connect to.

Fix this by making \l+ also check
pg_has_role('pg_read_all_stats', 'USAGE'), matching
pg_database_size()'s permission rules.

For back branches, emit the pg_read_all_stats check only when
connected to PostgreSQL 10 or later, since earlier releases do not have
that predefined role.

Backpatch to all supported versions.

Author: Christoph Berg <myon@debian.org>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/amCo6qRmnfPVk4-V@msg.df7cb.de
Backpatch-through: 14

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 56c2692e618cbad79b9e22d50ce30b41d14d2644..3ec0a3c3b34049f3ac49563d61a2df07464574d6 100644 (file)
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -2817,8 +2817,9 @@ SELECT
         are displayed in expanded mode.
         If <literal>+</literal> is appended to the command name, database
         sizes, default tablespaces, and descriptions are also displayed.
-        (Size information is only available for databases that the current
-        user can connect to.)
+        Size information is available for databases on which the current user has
+        <literal>CONNECT</literal> privilege, or if the current user is a superuser
+        or has privileges of the <literal>pg_read_all_stats</literal> role.
         </para>
         </listitem>
       </varlistentry>

diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index a2f09c26369900065adcc2e7f89408b687f03c3f..ad9c8affb4f2f857180fdc3725153f0ece15f071 100644 (file)
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -986,7 +986,8 @@ listAllDbs(const char *pattern, bool verbose)
        printACLColumn(&buf, "d.datacl");
        if (verbose)
                appendPQExpBuffer(&buf,
-                                                 ",\n  CASE WHEN pg_catalog.has_database_privilege(d.datname, 'CONNECT')\n"
+                                                 ",\n  CASE WHEN pg_catalog.has_database_privilege(d.datname, 'CONNECT') OR\n"
+                                                 "               pg_catalog.pg_has_role('pg_read_all_stats', 'USAGE')\n"
                                                  "       THEN pg_catalog.pg_size_pretty(pg_catalog.pg_database_size(d.datname))\n"
                                                  "       ELSE 'No Access'\n"
                                                  "  END as \"%s\""