Require the schema qualification in pg_temp.type_name(arg).

Commit aa27977fe21a7dfa4da4376ad66ae37cb8f0d0b5 introduced this
restriction for pg_temp.function_name(arg); do likewise for types
created in temporary schemas.  Programs that this breaks should add
"pg_temp." schema qualification or switch to arg::type_name syntax.
Back-patch to 9.4 (all supported versions).

Reviewed by Tom Lane.  Reported by Tom Lane.

Security: CVE-2019-10208

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index c485f4635db0cb0d6e18a5a6dba5dde2328520cb..3483ad66cd4df38610ee43bd954acb90838a0d32 100644 (file)
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -5967,6 +5967,10 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         be searched <emphasis>before</> searching any of the path items.
        </para>
 
+       <!-- To further split hairs, funcname('foo') does not use the temporary
+            schema, even when it considers typname='funcname'.  This paragraph
+            refers to function names in a loose sense, "pg_proc.proname or
+            func_name grammar production". -->
        <para>
         Likewise, the current session's temporary-table schema,
         <literal>pg_temp_<replaceable>nnn</></>, is always searched if it

diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
index 193c3dadbf2676dec0a7b14c5470ef807282d400..009393de3465ba987183c73b9b10b0b28dba6460 100644 (file)
--- a/src/backend/catalog/namespace.c
+++ b/src/backend/catalog/namespace.c
@@ -753,13 +753,23 @@ RelationIsVisible(Oid relid)
 
 /*
  * TypenameGetTypid
+ *     Wrapper for binary compatibility.
+ */
+Oid
+TypenameGetTypid(const char *typname)
+{
+   return TypenameGetTypidExtended(typname, true);
+}
+
+/*
+ * TypenameGetTypidExtended
  *     Try to resolve an unqualified datatype name.
  *     Returns OID if type found in search path, else InvalidOid.
  *
  * This is essentially the same as RelnameGetRelid.
  */
 Oid
-TypenameGetTypid(const char *typname)
+TypenameGetTypidExtended(const char *typname, bool temp_ok)
 {
    Oid         typid;
    ListCell   *l;
@@ -770,6 +780,9 @@ TypenameGetTypid(const char *typname)
    {
        Oid         namespaceId = lfirst_oid(l);
 
+       if (!temp_ok && namespaceId == myTempNamespace)
+           continue;           /* do not look in temp namespace */
+
        typid = GetSysCacheOid2(TYPENAMENSP,
                                PointerGetDatum(typname),
                                ObjectIdGetDatum(namespaceId));

diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 61af484feebafbbc5e76bab805488e3c8e345acf..82ae62b61236ae77c6d8003575249cc2ef3dfdb7 100644 (file)
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -1746,7 +1746,12 @@ FuncNameAsType(List *funcname)
    Oid         result;
    Type        typtup;
 
-   typtup = LookupTypeName(NULL, makeTypeNameFromNameList(funcname), NULL, false);
+   /*
+    * temp_ok=false protects the <refsect1 id="sql-createfunction-security">
+    * contract for writing SECURITY DEFINER functions safely.
+    */
+   typtup = LookupTypeNameExtended(NULL, makeTypeNameFromNameList(funcname),
+                                   NULL, false, false);
    if (typtup == NULL)
        return InvalidOid;
 

diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
index a8bb4721f3048253188f5bd8ccbf4e0b15df05b4..72560404b02fbb900f030f16cd90555267f68c29 100644 (file)
--- a/src/backend/parser/parse_type.c
+++ b/src/backend/parser/parse_type.c
@@ -33,6 +33,18 @@ static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
 
 /*
  * LookupTypeName
+ *     Wrapper for typical case.
+ */
+Type
+LookupTypeName(ParseState *pstate, const TypeName *typeName,
+              int32 *typmod_p, bool missing_ok)
+{
+   return LookupTypeNameExtended(pstate,
+                                 typeName, typmod_p, true, missing_ok);
+}
+
+/*
+ * LookupTypeNameExtended
  *     Given a TypeName object, lookup the pg_type syscache entry of the type.
  *     Returns NULL if no such type can be found.  If the type is found,
  *     the typmod value represented in the TypeName struct is computed and
@@ -51,11 +63,17 @@ static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
  * found but is a shell, and there is typmod decoration, an error will be
  * thrown --- this is intentional.
  *
+ * If temp_ok is false, ignore types in the temporary namespace.  Pass false
+ * when the caller will decide, using goodness of fit criteria, whether the
+ * typeName is actually a type or something else.  If typeName always denotes
+ * a type (or denotes nothing), pass true.
+ *
  * pstate is only used for error location info, and may be NULL.
  */
 Type
-LookupTypeName(ParseState *pstate, const TypeName *typeName,
-              int32 *typmod_p, bool missing_ok)
+LookupTypeNameExtended(ParseState *pstate,
+                      const TypeName *typeName, int32 *typmod_p,
+                      bool temp_ok, bool missing_ok)
 {
    Oid         typoid;
    HeapTuple   tup;
@@ -172,7 +190,7 @@ LookupTypeName(ParseState *pstate, const TypeName *typeName,
        else
        {
            /* Unqualified type name, so search the search path */
-           typoid = TypenameGetTypid(typname);
+           typoid = TypenameGetTypidExtended(typname, temp_ok);
        }
 
        /* If an array reference, return the array type instead */

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index f6f2b7c529df47159e3f4bccc165a0834c0db1d8..c58de5917065eea4b55b0a41d83b9a83c2cfb30d 100644 (file)
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8767,6 +8767,14 @@ get_coercion_expr(Node *arg, deparse_context *context,
        if (!PRETTY_PAREN(context))
            appendStringInfoChar(buf, ')');
    }
+
+   /*
+    * Never emit resulttype(arg) functional notation. A pg_proc entry could
+    * take precedence, and a resulttype in pg_temp would require schema
+    * qualification that format_type_with_typemod() would usually omit. We've
+    * standardized on arg::resulttype, but CAST(arg AS resulttype) notation
+    * would work fine.
+    */
    appendStringInfo(buf, "::%s",
                     format_type_with_typemod(resulttype, resulttypmod));
 }

diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
index eee94d862267440c89c7d296805c14bc5b41a042..a399933c183d9f8b2f31d83af067b383ab3551b2 100644 (file)
--- a/src/include/catalog/namespace.h
+++ b/src/include/catalog/namespace.h
@@ -66,6 +66,7 @@ extern Oid    RelnameGetRelid(const char *relname);
 extern bool RelationIsVisible(Oid relid);
 
 extern Oid TypenameGetTypid(const char *typname);
+extern Oid TypenameGetTypidExtended(const char *typname, bool temp_ok);
 extern bool TypeIsVisible(Oid typid);
 
 extern FuncCandidateList FuncnameGetCandidates(List *names,

diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
index ba580beda3a230de059ea57cb4c0f64ae6937e6b..391b43ec958421378ba3dd0fa1391080aea294be 100644 (file)
--- a/src/include/parser/parse_type.h
+++ b/src/include/parser/parse_type.h
@@ -21,6 +21,9 @@ typedef HeapTuple Type;
 
 extern Type LookupTypeName(ParseState *pstate, const TypeName *typeName,
               int32 *typmod_p, bool missing_ok);
+extern Type LookupTypeNameExtended(ParseState *pstate,
+                                  const TypeName *typeName, int32 *typmod_p,
+                                  bool temp_ok, bool missing_ok);
 extern Oid LookupTypeNameOid(ParseState *pstate, const TypeName *typeName,
                  bool missing_ok);
 extern Type typenameType(ParseState *pstate, const TypeName *typeName,

diff --git a/src/test/regress/expected/temp.out b/src/test/regress/expected/temp.out
index addf1ec444397cbeae37d2ac1838503646d488d4..0df7ba3ae1a3c0baa95d3d71254aaf2e9152a562 100644 (file)
--- a/src/test/regress/expected/temp.out
+++ b/src/test/regress/expected/temp.out
@@ -199,3 +199,18 @@ select pg_temp.whoami();
 (1 row)
 
 drop table public.whereami;
+-- types in temp schema
+set search_path = pg_temp, public;
+create domain pg_temp.nonempty as text check (value <> '');
+-- function-syntax invocation of types matches rules for functions
+select nonempty('');
+ERROR:  function nonempty(unknown) does not exist
+LINE 1: select nonempty('');
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+select pg_temp.nonempty('');
+ERROR:  value for domain nonempty violates check constraint "nonempty_check"
+-- other syntax matches rules for tables
+select ''::nonempty;
+ERROR:  value for domain nonempty violates check constraint "nonempty_check"
+reset search_path;

diff --git a/src/test/regress/sql/temp.sql b/src/test/regress/sql/temp.sql
index 5183c727f5e70139d71ab345ce548f8d175baf06..6936b999295e8c6a928fcbf85cd9281788fe3283 100644 (file)
--- a/src/test/regress/sql/temp.sql
+++ b/src/test/regress/sql/temp.sql
@@ -151,3 +151,14 @@ select whoami();
 select pg_temp.whoami();
 
 drop table public.whereami;
+
+-- types in temp schema
+set search_path = pg_temp, public;
+create domain pg_temp.nonempty as text check (value <> '');
+-- function-syntax invocation of types matches rules for functions
+select nonempty('');
+select pg_temp.nonempty('');
+-- other syntax matches rules for tables
+select ''::nonempty;
+
+reset search_path;