On Sat, Dec 25, 2021 at 02:36:27PM +0000, Erki Eessaar wrote:
>
> Hello
>
> PostgreSQL 14 added the feature: "Allow SQL-language functions and procedures
> to use SQL-standard function bodies."
>
> If I understand correctly, then in this case the system will track
> dependencies between tables and routines that use the tables. Thus, the
> SECURITY DEFINER routines that use the new approach do not require the
> following mitigation, i.e., SET search_path= is not needed. The following part
> of documentation does not mention this.
>
> https://www.postgresql.org/docs/current/sql-createfunction.html#
> SQL-CREATEFUNCTION-SECURITY
>
> [elephant] PostgreSQL: Documentation: 14: CREATE FUNCTION
> Overloading. PostgreSQL allows function overloading; that is, the
> same name can be used for several different functions so long as
> they have distinct input argument types.Whether or not you use it,
> this capability entails security precautions when calling functions
> in databases where some users mistrust other users; see Section
> 10.3.. Two functions are considered the same if they have the same
> ...
> www.postgresql.org
I have written the attached patch to mention this issue about sql_body
functions.
--
Bruce Momjian <[email protected]> https://momjian.us
EDB https://enterprisedb.com
Indecision is a decision. Inaction is an action. Mark Batterson
diff --git a/doc/src/sgml/ref/create_function.sgml b/doc/src/sgml/ref/create_function.sgml
index 7e6d52c7dc..976d4caad6 100644
--- a/doc/src/sgml/ref/create_function.sgml
+++ b/doc/src/sgml/ref/create_function.sgml
@@ -779,7 +779,10 @@ SELECT * FROM dup(42);
<para>
Because a <literal>SECURITY DEFINER</literal> function is executed
with the privileges of the user that owns it, care is needed to
- ensure that the function cannot be misused. For security,
+ ensure that the function cannot be misused. This is particularly
+ important for non-<replaceable>sql_body</replaceable> functions because
+ their function bodies are evaulated at run-time, not creation time.
+ For security,
<xref linkend="guc-search-path"/> should be set to exclude any schemas
writable by untrusted users. This prevents
malicious users from creating objects (e.g., tables, functions, and
