Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit03813a5

Browse files
committed
Prevent possible double-free when update trigger returns old tuple.
This is a variant of the problem fixed in commit25b6925, whichunfortunately we failed to detect at the time. If an update triggerreturns the "old" tuple, as it's entitled to do, then a subsequentiteration of the loop in ExecBRUpdateTriggers would have "oldtuple"equal to "trigtuple" and would fail to notice that it shouldn'tfree that.In addition to fixing the code, extend the test case added by25b6925 so that it covers multiple-trigger-iterations cases.This problem does not manifest in v12/HEAD, as a result of therelevant code having been largely rewritten for slotification.However, include the test case into v12/HEAD anyway, since thisis clearly an area that someone could break again in future.Per report from Piotr Gabriel Kosinski. Back-patch into allsupported branches, since the bug seems quite old.Diagnosis and code fix by Thomas Munro, test case by me.Discussion:https://postgr.es/m/CAFMLSdP0rd7LqC3j-H6Fh51FYSt5A10DDh-3=W4PPc4LLUQ8YQ@mail.gmail.com
1 parenta450469 commit03813a5

File tree

2 files changed

+105
-0
lines changed

2 files changed

+105
-0
lines changed

‎src/test/regress/expected/triggers.out

Lines changed: 70 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -144,6 +144,76 @@ select * from trigtest;
144144
----+----
145145
(0 rows)
146146

147+
-- Also check what happens when such a trigger runs before or after others
148+
create function f1_times_10() returns trigger as
149+
$$ begin new.f1 := new.f1 * 10; return new; end $$ language plpgsql;
150+
create trigger trigger_alpha
151+
before insert or update on trigtest
152+
for each row execute procedure f1_times_10();
153+
insert into trigtest values(1, 'foo');
154+
select * from trigtest;
155+
f1 | f2
156+
----+-----
157+
10 | foo
158+
(1 row)
159+
160+
update trigtest set f2 = f2 || 'bar';
161+
select * from trigtest;
162+
f1 | f2
163+
----+-----
164+
10 | foo
165+
(1 row)
166+
167+
delete from trigtest;
168+
select * from trigtest;
169+
f1 | f2
170+
----+----
171+
(0 rows)
172+
173+
create trigger trigger_zed
174+
before insert or update on trigtest
175+
for each row execute procedure f1_times_10();
176+
insert into trigtest values(1, 'foo');
177+
select * from trigtest;
178+
f1 | f2
179+
-----+-----
180+
100 | foo
181+
(1 row)
182+
183+
update trigtest set f2 = f2 || 'bar';
184+
select * from trigtest;
185+
f1 | f2
186+
------+-----
187+
1000 | foo
188+
(1 row)
189+
190+
delete from trigtest;
191+
select * from trigtest;
192+
f1 | f2
193+
----+----
194+
(0 rows)
195+
196+
drop trigger trigger_alpha on trigtest;
197+
insert into trigtest values(1, 'foo');
198+
select * from trigtest;
199+
f1 | f2
200+
----+-----
201+
10 | foo
202+
(1 row)
203+
204+
update trigtest set f2 = f2 || 'bar';
205+
select * from trigtest;
206+
f1 | f2
207+
-----+-----
208+
100 | foo
209+
(1 row)
210+
211+
delete from trigtest;
212+
select * from trigtest;
213+
f1 | f2
214+
----+----
215+
(0 rows)
216+
147217
drop table trigtest;
148218
create sequence ttdummy_seq increment 10 start 0 minvalue 0;
149219
create table tttest (

‎src/test/regress/sql/triggers.sql

Lines changed: 35 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -117,6 +117,41 @@ select * from trigtest;
117117
deletefrom trigtest;
118118
select*from trigtest;
119119

120+
-- Also check what happens when such a trigger runs before or after others
121+
createfunctionf1_times_10() returns triggeras
122+
$$beginnew.f1 :=new.f1*10; return new; end $$ language plpgsql;
123+
124+
createtriggertrigger_alpha
125+
before insertorupdateon trigtest
126+
for each row execute procedure f1_times_10();
127+
128+
insert into trigtestvalues(1,'foo');
129+
select*from trigtest;
130+
update trigtestset f2= f2||'bar';
131+
select*from trigtest;
132+
deletefrom trigtest;
133+
select*from trigtest;
134+
135+
createtriggertrigger_zed
136+
before insertorupdateon trigtest
137+
for each row execute procedure f1_times_10();
138+
139+
insert into trigtestvalues(1,'foo');
140+
select*from trigtest;
141+
update trigtestset f2= f2||'bar';
142+
select*from trigtest;
143+
deletefrom trigtest;
144+
select*from trigtest;
145+
146+
droptrigger trigger_alphaon trigtest;
147+
148+
insert into trigtestvalues(1,'foo');
149+
select*from trigtest;
150+
update trigtestset f2= f2||'bar';
151+
select*from trigtest;
152+
deletefrom trigtest;
153+
select*from trigtest;
154+
120155
droptable trigtest;
121156

122157
createsequencettdummy_seq increment10 start0 minvalue0;

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp