postgres.git / summary / log / commit / refs
commit 2f48b4f075fb6672e1acbc3707cb0ef82030f2bf
Author: Richard Guo <rguo@postgresql.org>
Date: Thu May 15 08:09:04 2025 +0000
First released in: 18.0, 15.14, 16.10, 17.6
Fix Assert failure in XMLTABLE parser
In an XMLTABLE expression, columns can be marked NOT NULL, and the
parser internally fabricates an option named "is_not_null" to
represent this. However, the parser also allows users to specify
arbitrary option names. This creates a conflict: a user can
explicitly use "is_not_null" as an option name and assign it a
non-Boolean value, which violates internal assumptions and triggers an
assertion failure.
To fix, this patch checks whether a user-supplied name collides with
the internally reserved option name and raises an error if so.
Additionally, the internal name is renamed to "__pg__is_not_null" to
further reduce the risk of collision with user-defined names.
Reported-by: Евгений Горбанев <gorbanyoves@basealt.ru>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/6bac9886-65bf-4cec-96bd-e304159f28db@basealt.ru
Backpatch-through: 15
src/backend/parser/gram.y | 15 +++++++++++----
src/test/regress/expected/xml.out | 4 ++++
src/test/regress/expected/xml_1.out | 4 ++++
src/test/regress/expected/xml_2.out | 4 ++++
src/test/regress/sql/xml.sql | 2 ++
5 files changed, 25 insertions(+), 4 deletions(-)
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 08e2195fa48..f230c5ff9e7 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -14048,7 +14048,7 @@ xmltable_column_el:
parser_errposition(defel->location)));
fc->colexpr = defel->arg;
}
- else if (strcmp(defel->defname, "is_not_null") == 0)
+ else if (strcmp(defel->defname, "__pg__is_not_null") == 0)
{
if (nullability_seen)
ereport(ERROR,
@@ -14091,13 +14091,20 @@ xmltable_column_option_list:
xmltable_column_option_el:
IDENT b_expr
- { $$ = makeDefElem($1, $2, @1); }
+ {
+ if (strcmp($1, "__pg__is_not_null") == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("option name \"%s\" cannot be used in XMLTABLE", $1),
+ parser_errposition(@1)));
+ $$ = makeDefElem($1, $2, @1);
+ }
| DEFAULT b_expr
{ $$ = makeDefElem("default", $2, @1); }
| NOT NULL_P
- { $$ = makeDefElem("is_not_null", (Node *) makeBoolean(true), @1); }
+ { $$ = makeDefElem("__pg__is_not_null", (Node *) makeBoolean(true), @1); }
| NULL_P
- { $$ = makeDefElem("is_not_null", (Node *) makeBoolean(false), @1); }
+ { $$ = makeDefElem("__pg__is_not_null", (Node *) makeBoolean(false), @1); }
| PATH b_expr
{ $$ = makeDefElem("path", $2, @1); }
;
diff --git a/src/test/regress/expected/xml.out b/src/test/regress/expected/xml.out
index 868479997d8..21677b609a6 100644
--- a/src/test/regress/expected/xml.out
+++ b/src/test/regress/expected/xml.out
@@ -1373,6 +1373,10 @@ EXPLAIN (COSTS OFF, VERBOSE) SELECT * FROM xmltableview1;
-- errors
SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp) AS f (v1, v2);
ERROR: XMLTABLE function has 1 columns available but 2 columns specified
+SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_not_null 1) AS f (v1);
+ERROR: option name "__pg__is_not_null" cannot be used in XMLTABLE
+LINE 1: ...MLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_n...
+ ^
-- XMLNAMESPACES tests
SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
'/zz:rows/zz:row'
diff --git a/src/test/regress/expected/xml_1.out b/src/test/regress/expected/xml_1.out
index 4e8f65de041..852444cb052 100644
--- a/src/test/regress/expected/xml_1.out
+++ b/src/test/regress/expected/xml_1.out
@@ -1047,6 +1047,10 @@ EXPLAIN (COSTS OFF, VERBOSE) SELECT * FROM xmltableview1;
-- errors
SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp) AS f (v1, v2);
ERROR: XMLTABLE function has 1 columns available but 2 columns specified
+SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_not_null 1) AS f (v1);
+ERROR: option name "__pg__is_not_null" cannot be used in XMLTABLE
+LINE 1: ...MLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_n...
+ ^
-- XMLNAMESPACES tests
SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
'/zz:rows/zz:row'
diff --git a/src/test/regress/expected/xml_2.out b/src/test/regress/expected/xml_2.out
index 4e71cd4f266..e35fc58f098 100644
--- a/src/test/regress/expected/xml_2.out
+++ b/src/test/regress/expected/xml_2.out
@@ -1359,6 +1359,10 @@ EXPLAIN (COSTS OFF, VERBOSE) SELECT * FROM xmltableview1;
-- errors
SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp) AS f (v1, v2);
ERROR: XMLTABLE function has 1 columns available but 2 columns specified
+SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_not_null 1) AS f (v1);
+ERROR: option name "__pg__is_not_null" cannot be used in XMLTABLE
+LINE 1: ...MLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_n...
+ ^
-- XMLNAMESPACES tests
SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
'/zz:rows/zz:row'
diff --git a/src/test/regress/sql/xml.sql b/src/test/regress/sql/xml.sql
index 4c3520ce898..0ea4f508837 100644
--- a/src/test/regress/sql/xml.sql
+++ b/src/test/regress/sql/xml.sql
@@ -435,6 +435,8 @@ EXPLAIN (COSTS OFF, VERBOSE) SELECT * FROM xmltableview1;
-- errors
SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp) AS f (v1, v2);
+SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp __pg__is_not_null 1) AS f (v1);
+
-- XMLNAMESPACES tests
SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
'/zz:rows/zz:row'
[parent: c5639196caf7]