database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-30 11:03:19 +03:00
Code Activity

Enforce superuser permissions checks during ALTER ROLE/DATABASE SET, rather

Browse Source 
than during define_custom_variable().  This entails rejecting an ALTER
command if the target variable doesn't have a known (non-placeholder)
definition, unless the calling user is superuser.  When the variable *is*
known, we can correctly apply the rule that only superusers can issue ALTER
for SUSET parameters.  This allows define_custom_variable to apply ALTER's
values for SUSET parameters at module load time, secure in the knowledge
that only a superuser could have set the ALTER value.  This change fixes a
longstanding gotcha in the usage of SUSET-level custom parameters; which
is a good thing to fix now that plpgsql defines such a parameter.
This commit is contained in:
Tom Lane
2010-04-21 20:54:19 +00:00
parent f6e092701c
commit a6dcd19a2a
2 changed files with 158 additions and 64 deletions
Download Patch File Download Diff File Expand all files Collapse all files

49
doc/src/sgml/ref/alter_role.sgml
View File

@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_role.sgml,v 1.16 2010/04/03 07:22:57 petere Exp $
$PostgreSQL: pgsql/doc/src/sgml/ref/alter_role.sgml,v 1.17 2010/04/21 20:54:19 tgl Exp $
PostgreSQL documentation
-->
@ -24,7 +24,7 @@ PostgreSQL documentation
ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ [ WITH ] <replaceable class="PARAMETER">option</replaceable> [ ... ] ]
<phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
SUPERUSER | NOSUPERUSER
| CREATEDB | NOCREATEDB
| CREATEROLE | NOCREATEROLE
@ -33,7 +33,7 @@ ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ [ WITH ] <replace
| LOGIN | NOLOGIN
| CONNECTION LIMIT <replaceable class="PARAMETER">connlimit</replaceable>
| [ ENCRYPTED | UNENCRYPTED ] PASSWORD '<replaceable class="PARAMETER">password</replaceable>'
| VALID UNTIL '<replaceable class="PARAMETER">timestamp</replaceable>'
| VALID UNTIL '<replaceable class="PARAMETER">timestamp</replaceable>'
ALTER ROLE <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable>new_name</replaceable>
@ -54,7 +54,7 @@ ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ IN DATABASE <repl
<para>
The first variant of this command listed in the synopsis can change
many of the role attributes that can be specified in
many of the role attributes that can be specified in
<xref linkend="sql-createrole">.
(All the possible attributes are covered,
except that there are no options for adding or removing memberships; use
@ -79,20 +79,24 @@ ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ IN DATABASE <repl
password is <literal>MD5</>-encrypted.
</para>
<para>
The remaining variants change a role's session default for a configuration variable
for all databases or, when the <literal>IN DATABASE</literal> clause is specified,
for the named database. Whenever the role subsequently
<para>
The remaining variants change a role's session default for a configuration
variable, either for all databases or, when the <literal>IN
DATABASE</literal> clause is specified, only for sessions in
the named database. Whenever the role subsequently
starts a new session, the specified value becomes the session
default, overriding whatever setting is present in
<filename>postgresql.conf</> or has been received from the postgres
command line. This only happens at login time, so configuration
settings associated with a role to which you've <xref
linkend="sql-set-role"> will be ignored. Settings set to
a role directly are overridden by any database specific settings attached to a role.
command line. This only happens at login time; executing
<xref linkend="sql-set-role"> or
<xref linkend="sql-set-session-authorization"> does not cause new
configuration values to be set.
Settings set for all databases are overridden by database-specific settings
attached to a role.
Superusers can change anyone's session defaults. Roles having
<literal>CREATEROLE</> privilege can change defaults for non-superuser
roles. Certain variables cannot be set this way, or can only be
roles. Ordinary roles can only set defaults for themselves.
Certain configuration variables cannot be set this way, or can only be
set if a superuser issues the command.
</para>
</refsect1>
@ -169,14 +173,15 @@ ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ IN DATABASE <repl
<literal>RESET ALL</literal> to clear all role-specific settings.
<literal>SET FROM CURRENT</> saves the session's current value of
the parameter as the role-specific value.
If used in conjunction with <literal>IN DATABASE</literal>, the configuration
If <literal>IN DATABASE</literal> is specified, the configuration
parameter is set or removed for the given role and database only.
</para>
<para>
Role-specific variable setting take effect only at login;
<xref linkend="sql-set-role">
does not process role-specific variable settings.
Role-specific variable settings take effect only at login;
<xref linkend="sql-set-role"> and
<xref linkend="sql-set-session-authorization">
do not process role-specific variable settings.
</para>
<para>
@ -210,8 +215,8 @@ ALTER ROLE <replaceable class="PARAMETER">name</replaceable> [ IN DATABASE <repl
in cleartext, and it might also be logged in the client's command
history or the server log. <xref linkend="app-psql">
contains a command
<command>\password</command> that can be used to safely change a
role's password.
<command>\password</command> that can be used to change a
role's password without exposing the cleartext password.
</para>
<para>
@ -276,8 +281,8 @@ ALTER ROLE worker_bee SET maintenance_work_mem = 100000;
</para>
<para>
Give a role a non-default, database-specific setting of the
<xref linkend="guc-client-min-messages"> parameter:
Give a role a non-default, database-specific setting of the
<xref linkend="guc-client-min-messages"> parameter:
<programlisting>
ALTER ROLE fred IN DATABASE devel SET client_min_messages = DEBUG;
@ -287,7 +292,7 @@ ALTER ROLE fred IN DATABASE devel SET client_min_messages = DEBUG;
<refsect1>
<title>Compatibility</title>
<para>
The <command>ALTER ROLE</command> statement is a
<productname>PostgreSQL</productname> extension.