1
0
mirror of https://github.com/postgres/postgres.git synced 2025-12-12 02:37:31 +03:00

Fix plpython crash when returning string representation of a RECORD result.

PLyString_ToComposite() blithely overwrote proc->result.out.d, even though
for a composite result type the other union variant proc->result.out.r is
the one that should be valid.  This could result in a crash if out.r had
in fact been filled in (proc->result.is_rowtype == 1) and then somebody
later attempted to use that data; as per bug #13579 from Paweł Michalak.

Just to add insult to injury, it didn't work for RECORD results anyway,
because record_in() would refuse the case.

Fix by doing the I/O function lookup in a local PLyTypeInfo variable,
as we were doing already in PLyObject_ToComposite().  This is not a great
technique because any fn_extra data allocated by the input function will
be leaked permanently (thanks to using TopMemoryContext as fn_mcxt).
But that's a pre-existing issue that is much less serious than a crash,
so leave it to be fixed separately.

This bug would be a potential security issue, except that plpython is
only available to superusers and the crash requires coding the function
in a way that didn't work before today's patches.

Add regression test cases covering all the supported methods of converting
composite results.

Back-patch to 9.1 where the faulty coding was introduced.
This commit is contained in:
Tom Lane
2015-08-21 12:21:37 -04:00
parent 09b3d27256
commit f469f634ad
3 changed files with 259 additions and 2 deletions

View File

@@ -32,10 +32,40 @@ elif typ == 'obj':
type_record.first = first
type_record.second = second
return type_record
elif typ == 'str':
return "('%s',%r)" % (first, second)
$$ LANGUAGE plpythonu;
SELECT * FROM multiout_record_as('dict', 'foo', 1, 'f');
SELECT multiout_record_as('dict', 'foo', 1, 'f');
SELECT * FROM multiout_record_as('dict', null, null, false);
SELECT * FROM multiout_record_as('dict', 'one', null, false);
SELECT * FROM multiout_record_as('dict', null, 2, false);
SELECT * FROM multiout_record_as('dict', 'three', 3, false);
SELECT * FROM multiout_record_as('dict', null, null, true);
SELECT * FROM multiout_record_as('tuple', null, null, false);
SELECT * FROM multiout_record_as('tuple', 'one', null, false);
SELECT * FROM multiout_record_as('tuple', null, 2, false);
SELECT * FROM multiout_record_as('tuple', 'three', 3, false);
SELECT * FROM multiout_record_as('tuple', null, null, true);
SELECT * FROM multiout_record_as('list', null, null, false);
SELECT * FROM multiout_record_as('list', 'one', null, false);
SELECT * FROM multiout_record_as('list', null, 2, false);
SELECT * FROM multiout_record_as('list', 'three', 3, false);
SELECT * FROM multiout_record_as('list', null, null, true);
SELECT * FROM multiout_record_as('obj', null, null, false);
SELECT * FROM multiout_record_as('obj', 'one', null, false);
SELECT * FROM multiout_record_as('obj', null, 2, false);
SELECT * FROM multiout_record_as('obj', 'three', 3, false);
SELECT * FROM multiout_record_as('obj', null, null, true);
SELECT * FROM multiout_record_as('str', 'one', 1, false);
SELECT * FROM multiout_record_as('str', 'one', 2, false);
SELECT *, s IS NULL AS snull FROM multiout_record_as('tuple', 'xxx', NULL, 'f') AS f(f, s);
SELECT *, f IS NULL AS fnull, s IS NULL AS snull FROM multiout_record_as('tuple', 'xxx', 1, 't') AS f(f, s);
SELECT * FROM multiout_record_as('obj', NULL, 10, 'f');
@@ -92,18 +122,29 @@ elif typ == 'dict':
d = {'first': n * 2, 'second': n * 3, 'extra': 'not important'}
elif typ == 'tuple':
d = (n * 2, n * 3)
elif typ == 'list':
d = [ n * 2, n * 3 ]
elif typ == 'obj':
class d: pass
d.first = n * 2
d.second = n * 3
elif typ == 'str':
d = "(%r,%r)" % (n * 2, n * 3)
for i in range(n):
yield (i, d)
$$ LANGUAGE plpythonu;
SELECT * FROM multiout_composite(2);
SELECT * FROM multiout_table_type_setof('dict', 'f', 3);
SELECT * FROM multiout_table_type_setof('dict', 'f', 7);
SELECT * FROM multiout_table_type_setof('tuple', 'f', 2);
SELECT * FROM multiout_table_type_setof('tuple', 'f', 3);
SELECT * FROM multiout_table_type_setof('list', 'f', 2);
SELECT * FROM multiout_table_type_setof('list', 'f', 3);
SELECT * FROM multiout_table_type_setof('obj', 'f', 4);
SELECT * FROM multiout_table_type_setof('obj', 'f', 5);
SELECT * FROM multiout_table_type_setof('str', 'f', 6);
SELECT * FROM multiout_table_type_setof('str', 'f', 7);
SELECT * FROM multiout_table_type_setof('dict', 't', 3);
-- check what happens if a type changes under us