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

Commit4989ce7

Browse files
committed
MERGE ... DO NOTHING: require SELECT privileges
Verify that a user running MERGE with a DO NOTHING clause hasprivileges to read the table, even if no columns are referenced. Suchprivileges were already required if the ON clause or any of the WHENconditions referenced any column at all, so there's no functional changein practice.This change fixes an assertion failure in the case where no column isreferenced by the command and the WHEN clauses are all DO NOTHING.Backpatch to 15, where MERGE was introduced.Reported-by: Alena Rybakina <a.rybakina@postgrespro.ru>Reported-by: Alexander Lakhin <exclusion@gmail.com>Discussion:https://postgr.es/m/4d65a385-7efa-4436-a825-0869f89d9d92@postgrespro.ru
1 parented345c2 commit4989ce7

File tree

3 files changed

+27
-1
lines changed

3 files changed

+27
-1
lines changed

‎src/backend/parser/parse_merge.c

Lines changed: 6 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -133,7 +133,11 @@ transformMergeStmt(ParseState *pstate, MergeStmt *stmt)
133133
intwhen_type= (mergeWhenClause->matched ?0 :1);
134134

135135
/*
136-
* Collect action types so we can check target permissions
136+
* Collect permissions to check, according to action types. We require
137+
* SELECT privileges for DO NOTHING because it'd be irregular to have
138+
* a target relation with zero privileges checked, in case DO NOTHING
139+
* is the only action. There's no damage from that: any meaningful
140+
* MERGE command requires at least some access to the table anyway.
137141
*/
138142
switch (mergeWhenClause->commandType)
139143
{
@@ -147,6 +151,7 @@ transformMergeStmt(ParseState *pstate, MergeStmt *stmt)
147151
targetPerms |=ACL_DELETE;
148152
break;
149153
caseCMD_NOTHING:
154+
targetPerms |=ACL_SELECT;
150155
break;
151156
default:
152157
elog(ERROR,"unknown action in MERGE WHEN clause");

‎src/test/regress/expected/merge.out

Lines changed: 10 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -3,6 +3,7 @@
33
--
44
CREATE USER regress_merge_privs;
55
CREATE USER regress_merge_no_privs;
6+
CREATE USER regress_merge_none;
67
DROP TABLE IF EXISTS target;
78
NOTICE: table "target" does not exist, skipping
89
DROP TABLE IF EXISTS source;
@@ -159,6 +160,14 @@ ERROR: cannot execute MERGE on relation "mv"
159160
DETAIL: This operation is not supported for materialized views.
160161
DROP MATERIALIZED VIEW mv;
161162
-- permissions
163+
SET SESSION AUTHORIZATION regress_merge_none;
164+
MERGE INTO target
165+
USING (SELECT 1)
166+
ON true
167+
WHEN MATCHED THEN
168+
DO NOTHING;
169+
ERROR: permission denied for table target
170+
SET SESSION AUTHORIZATION regress_merge_privs;
162171
MERGE INTO target
163172
USING source2
164173
ON target.tid = source2.sid
@@ -2248,3 +2257,4 @@ DROP TABLE source, source2;
22482257
DROP FUNCTION merge_trigfunc();
22492258
DROP USER regress_merge_privs;
22502259
DROP USER regress_merge_no_privs;
2260+
DROP USER regress_merge_none;

‎src/test/regress/sql/merge.sql

Lines changed: 11 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -4,6 +4,8 @@
44

55
CREATEUSERregress_merge_privs;
66
CREATEUSERregress_merge_no_privs;
7+
CREATEUSERregress_merge_none;
8+
79
DROPTABLE IF EXISTS target;
810
DROPTABLE IF EXISTS source;
911
CREATETABLEtarget (tidinteger, balanceinteger)
@@ -118,6 +120,14 @@ DROP MATERIALIZED VIEW mv;
118120

119121
-- permissions
120122

123+
SET SESSION AUTHORIZATION regress_merge_none;
124+
MERGE INTO target
125+
USING (SELECT1)
126+
ON true
127+
WHEN MATCHED THEN
128+
DO NOTHING;
129+
130+
SET SESSION AUTHORIZATION regress_merge_privs;
121131
MERGE INTO target
122132
USING source2
123133
ONtarget.tid=source2.sid
@@ -1471,3 +1481,4 @@ DROP TABLE source, source2;
14711481
DROPFUNCTION merge_trigfunc();
14721482
DROPUSER regress_merge_privs;
14731483
DROPUSER regress_merge_no_privs;
1484+
DROPUSER regress_merge_none;

0 commit comments

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