Skip to content

Commit e786be5

Browse files
michaelpqmichaelpq
committed
Fix crashes with currtid() and currtid2()
A relation that has no storage initializes rd_tableam to NULL, which caused those two functions to crash because of a pointer dereference. Note that in 11 and older versions, this has always failed with a confusing error "could not open file". These two functions are used by the Postgres ODBC driver, which requires them only when connecting to a backend strictly older than 8.1. When connected to 8.2 or a newer version, the driver uses a RETURNING clause instead whose support has been added in 8.2, so it should be possible to just remove both functions in the future. This is left as an issue to address later. While on it, add more regression tests for those functions as we never really had coverage for them, and for aggregates of TIDs. Reported-by: Jaime Casanova, via sqlsmith Author: Michael Paquier Reviewed-by: Álvaro Herrera Discussion: https://postgr.es/m/CAJGNTeO93u-5APMga6WH41eTZ3Uee9f3s8dCpA-GSSqNs1b=Ug@mail.gmail.com Backpatch-through: 12
1 parent af4ea50 commit e786be5

File tree

5 files changed

+182
-1
lines changed

5 files changed

+182
-1
lines changed

‎src/backend/utils/adt/tid.c‎

Lines changed: 11 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -31,6 +31,7 @@
3131
#include "parser/parsetree.h"
3232
#include "utils/acl.h"
3333
#include "utils/builtins.h"
34+
#include "utils/lsyscache.h"
3435
#include "utils/rel.h"
3536
#include "utils/snapmgr.h"
3637
#include "utils/varlena.h"
@@ -378,6 +379,11 @@ currtid_byreloid(PG_FUNCTION_ARGS)
378379
if (rel->rd_rel->relkind == RELKIND_VIEW)
379380
return currtid_for_view(rel, tid);
380381

382+
if (!RELKIND_HAS_STORAGE(rel->rd_rel->relkind))
383+
elog(ERROR, "cannot look at latest visible tid for relation \"%s.%s\"",
384+
get_namespace_name(RelationGetNamespace(rel)),
385+
RelationGetRelationName(rel));
386+
381387
ItemPointerCopy(tid, result);
382388

383389
snapshot = RegisterSnapshot(GetLatestSnapshot());
@@ -415,6 +421,11 @@ currtid_byrelname(PG_FUNCTION_ARGS)
415421
if (rel->rd_rel->relkind == RELKIND_VIEW)
416422
return currtid_for_view(rel, tid);
417423

424+
if (!RELKIND_HAS_STORAGE(rel->rd_rel->relkind))
425+
elog(ERROR, "cannot look at latest visible tid for relation \"%s.%s\"",
426+
get_namespace_name(RelationGetNamespace(rel)),
427+
RelationGetRelationName(rel));
428+
418429
result = (ItemPointer) palloc(sizeof(ItemPointerData));
419430
ItemPointerCopy(tid, result);
420431

‎src/test/regress/expected/tid.out‎

Lines changed: 106 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,106 @@
1+
-- tests for functions related to TID handling
2+
CREATE TABLE tid_tab (a int);
3+
-- min() and max() for TIDs
4+
INSERT INTO tid_tab VALUES (1), (2);
5+
SELECT min(ctid) FROM tid_tab;
6+
min
7+
-------
8+
(0,1)
9+
(1 row)
10+
11+
SELECT max(ctid) FROM tid_tab;
12+
max
13+
-------
14+
(0,2)
15+
(1 row)
16+
17+
TRUNCATE tid_tab;
18+
-- Tests for currtid() and currtid2() with various relation kinds
19+
-- Materialized view
20+
CREATE MATERIALIZED VIEW tid_matview AS SELECT a FROM tid_tab;
21+
SELECT currtid('tid_matview'::regclass::oid, '(0,1)'::tid); -- fails
22+
ERROR: tid (0, 1) is not valid for relation "tid_matview"
23+
SELECT currtid2('tid_matview'::text, '(0,1)'::tid); -- fails
24+
ERROR: tid (0, 1) is not valid for relation "tid_matview"
25+
INSERT INTO tid_tab VALUES (1);
26+
REFRESH MATERIALIZED VIEW tid_matview;
27+
SELECT currtid('tid_matview'::regclass::oid, '(0,1)'::tid); -- ok
28+
currtid
29+
---------
30+
(0,1)
31+
(1 row)
32+
33+
SELECT currtid2('tid_matview'::text, '(0,1)'::tid); -- ok
34+
currtid2
35+
----------
36+
(0,1)
37+
(1 row)
38+
39+
DROP MATERIALIZED VIEW tid_matview;
40+
TRUNCATE tid_tab;
41+
-- Sequence
42+
CREATE SEQUENCE tid_seq;
43+
SELECT currtid('tid_seq'::regclass::oid, '(0,1)'::tid); -- ok
44+
currtid
45+
---------
46+
(0,1)
47+
(1 row)
48+
49+
SELECT currtid2('tid_seq'::text, '(0,1)'::tid); -- ok
50+
currtid2
51+
----------
52+
(0,1)
53+
(1 row)
54+
55+
DROP SEQUENCE tid_seq;
56+
-- Index, fails with incorrect relation type
57+
CREATE INDEX tid_ind ON tid_tab(a);
58+
SELECT currtid('tid_ind'::regclass::oid, '(0,1)'::tid); -- fails
59+
ERROR: "tid_ind" is an index
60+
SELECT currtid2('tid_ind'::text, '(0,1)'::tid); -- fails
61+
ERROR: "tid_ind" is an index
62+
DROP INDEX tid_ind;
63+
-- Partitioned table, no storage
64+
CREATE TABLE tid_part (a int) PARTITION BY RANGE (a);
65+
SELECT currtid('tid_part'::regclass::oid, '(0,1)'::tid); -- fails
66+
ERROR: cannot look at latest visible tid for relation "public.tid_part"
67+
SELECT currtid2('tid_part'::text, '(0,1)'::tid); -- fails
68+
ERROR: cannot look at latest visible tid for relation "public.tid_part"
69+
DROP TABLE tid_part;
70+
-- Views
71+
-- ctid not defined in the view
72+
CREATE VIEW tid_view_no_ctid AS SELECT a FROM tid_tab;
73+
SELECT currtid('tid_view_no_ctid'::regclass::oid, '(0,1)'::tid); -- fails
74+
ERROR: currtid cannot handle views with no CTID
75+
SELECT currtid2('tid_view_no_ctid'::text, '(0,1)'::tid); -- fails
76+
ERROR: currtid cannot handle views with no CTID
77+
DROP VIEW tid_view_no_ctid;
78+
-- ctid fetched directly from the source table.
79+
CREATE VIEW tid_view_with_ctid AS SELECT ctid, a FROM tid_tab;
80+
SELECT currtid('tid_view_with_ctid'::regclass::oid, '(0,1)'::tid); -- fails
81+
ERROR: tid (0, 1) is not valid for relation "tid_tab"
82+
SELECT currtid2('tid_view_with_ctid'::text, '(0,1)'::tid); -- fails
83+
ERROR: tid (0, 1) is not valid for relation "tid_tab"
84+
INSERT INTO tid_tab VALUES (1);
85+
SELECT currtid('tid_view_with_ctid'::regclass::oid, '(0,1)'::tid); -- ok
86+
currtid
87+
---------
88+
(0,1)
89+
(1 row)
90+
91+
SELECT currtid2('tid_view_with_ctid'::text, '(0,1)'::tid); -- ok
92+
currtid2
93+
----------
94+
(0,1)
95+
(1 row)
96+
97+
DROP VIEW tid_view_with_ctid;
98+
TRUNCATE tid_tab;
99+
-- ctid attribute with incorrect data type
100+
CREATE VIEW tid_view_fake_ctid AS SELECT 1 AS ctid, 2 AS a;
101+
SELECT currtid('tid_view_fake_ctid'::regclass::oid, '(0,1)'::tid); -- fails
102+
ERROR: ctid isn't of type TID
103+
SELECT currtid2('tid_view_fake_ctid'::text, '(0,1)'::tid); -- fails
104+
ERROR: ctid isn't of type TID
105+
DROP VIEW tid_view_fake_ctid;
106+
DROP TABLE tid_tab CASCADE;

‎src/test/regress/parallel_schedule‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -78,7 +78,7 @@ test: brin gin gist spgist privileges init_privs security_label collate matview
7878
# ----------
7979
# Another group of parallel tests
8080
# ----------
81-
test: create_table_like alter_generic alter_operator misc async dbsize misc_functions sysviews tsrf tidscan collate.icu.utf8 incremental_sort
81+
test: create_table_like alter_generic alter_operator misc async dbsize misc_functions sysviews tsrf tid tidscan collate.icu.utf8 incremental_sort
8282

8383
# rules cannot run concurrently with any test that creates
8484
# a view or rule in the public schema

‎src/test/regress/serial_schedule‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -135,6 +135,7 @@ test: dbsize
135135
test: misc_functions
136136
test: sysviews
137137
test: tsrf
138+
test: tid
138139
test: tidscan
139140
test: collate.icu.utf8
140141
test: rules

‎src/test/regress/sql/tid.sql‎

Lines changed: 63 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,63 @@
1+
-- tests for functions related to TID handling
2+
3+
CREATE TABLE tid_tab (a int);
4+
5+
-- min() and max() for TIDs
6+
INSERT INTO tid_tab VALUES (1), (2);
7+
SELECT min(ctid) FROM tid_tab;
8+
SELECT max(ctid) FROM tid_tab;
9+
TRUNCATE tid_tab;
10+
11+
-- Tests for currtid() and currtid2() with various relation kinds
12+
13+
-- Materialized view
14+
CREATE MATERIALIZED VIEW tid_matview AS SELECT a FROM tid_tab;
15+
SELECT currtid('tid_matview'::regclass::oid, '(0,1)'::tid); -- fails
16+
SELECT currtid2('tid_matview'::text, '(0,1)'::tid); -- fails
17+
INSERT INTO tid_tab VALUES (1);
18+
REFRESH MATERIALIZED VIEW tid_matview;
19+
SELECT currtid('tid_matview'::regclass::oid, '(0,1)'::tid); -- ok
20+
SELECT currtid2('tid_matview'::text, '(0,1)'::tid); -- ok
21+
DROP MATERIALIZED VIEW tid_matview;
22+
TRUNCATE tid_tab;
23+
24+
-- Sequence
25+
CREATE SEQUENCE tid_seq;
26+
SELECT currtid('tid_seq'::regclass::oid, '(0,1)'::tid); -- ok
27+
SELECT currtid2('tid_seq'::text, '(0,1)'::tid); -- ok
28+
DROP SEQUENCE tid_seq;
29+
30+
-- Index, fails with incorrect relation type
31+
CREATE INDEX tid_ind ON tid_tab(a);
32+
SELECT currtid('tid_ind'::regclass::oid, '(0,1)'::tid); -- fails
33+
SELECT currtid2('tid_ind'::text, '(0,1)'::tid); -- fails
34+
DROP INDEX tid_ind;
35+
36+
-- Partitioned table, no storage
37+
CREATE TABLE tid_part (a int) PARTITION BY RANGE (a);
38+
SELECT currtid('tid_part'::regclass::oid, '(0,1)'::tid); -- fails
39+
SELECT currtid2('tid_part'::text, '(0,1)'::tid); -- fails
40+
DROP TABLE tid_part;
41+
42+
-- Views
43+
-- ctid not defined in the view
44+
CREATE VIEW tid_view_no_ctid AS SELECT a FROM tid_tab;
45+
SELECT currtid('tid_view_no_ctid'::regclass::oid, '(0,1)'::tid); -- fails
46+
SELECT currtid2('tid_view_no_ctid'::text, '(0,1)'::tid); -- fails
47+
DROP VIEW tid_view_no_ctid;
48+
-- ctid fetched directly from the source table.
49+
CREATE VIEW tid_view_with_ctid AS SELECT ctid, a FROM tid_tab;
50+
SELECT currtid('tid_view_with_ctid'::regclass::oid, '(0,1)'::tid); -- fails
51+
SELECT currtid2('tid_view_with_ctid'::text, '(0,1)'::tid); -- fails
52+
INSERT INTO tid_tab VALUES (1);
53+
SELECT currtid('tid_view_with_ctid'::regclass::oid, '(0,1)'::tid); -- ok
54+
SELECT currtid2('tid_view_with_ctid'::text, '(0,1)'::tid); -- ok
55+
DROP VIEW tid_view_with_ctid;
56+
TRUNCATE tid_tab;
57+
-- ctid attribute with incorrect data type
58+
CREATE VIEW tid_view_fake_ctid AS SELECT 1 AS ctid, 2 AS a;
59+
SELECT currtid('tid_view_fake_ctid'::regclass::oid, '(0,1)'::tid); -- fails
60+
SELECT currtid2('tid_view_fake_ctid'::text, '(0,1)'::tid); -- fails
61+
DROP VIEW tid_view_fake_ctid;
62+
63+
DROP TABLE tid_tab CASCADE;

0 commit comments

Comments
 (0)