From 670fb9f187cd75b6928cc044897a1f468439e19d Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathan@postgresql.org>
Date: Tue, 23 Jul 2024 21:59:02 -0500
Subject: [PATCH] Detect integer overflow in array_set_slice().
When provided an empty initial array, array_set_slice() fails to
check for overflow when computing the new array's dimensions.
While such overflows are ordinarily caught by ArrayGetNItems(),
commands with the following form are accepted:
INSERT INTO t (i[-2147483648:2147483647]) VALUES ('{}');
To fix, perform the hazardous computations using overflow-detecting
arithmetic routines. As with commit 18b585155a, the added test
cases generate errors that include a platform-dependent value, so
we again use psql's VERBOSITY parameter to suppress printing the
message text.
Reported-by: Alexander Lakhin
Author: Joseph Koshakow
Reviewed-by: Jian He
Discussion: https://postgr.es/m/31ad2cd1-db94-bdb3-f91a-65ffdb4bef95%40gmail.com
Backpatch-through: 12
---
src/backend/utils/adt/arrayfuncs.c | 9 ++++++++-
src/test/regress/expected/arrays.out | 4 ++++
src/test/regress/sql/arrays.sql | 2 ++
3 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 0071f7d2f4c..ce659b554ef 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -2899,7 +2899,14 @@ array_set_slice(Datum arraydatum,
errdetail("When assigning to a slice of an empty array value,"
" slice boundaries must be fully specified.")));
- dim[i] = 1 + upperIndx[i] - lowerIndx[i];
+ /* compute "upperIndx[i] - lowerIndx[i] + 1", detecting overflow */
+ if (pg_sub_s32_overflow(upperIndx[i], lowerIndx[i], &dim[i]) ||
+ pg_add_s32_overflow(dim[i], 1, &dim[i]))
+ ereport(ERROR,
+ (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+ errmsg("array size exceeds the maximum allowed (%d)",
+ (int) MaxArraySize)));
+
lb[i] = lowerIndx[i];
}
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 7f9b6932995..e45226737a3 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -1389,6 +1389,10 @@ update arr_pk_tbl set f1[2147483647] = 42 where pk = 10;
ERROR: 54000
update arr_pk_tbl set f1[2147483646:2147483647] = array[4,2] where pk = 10;
ERROR: 54000
+insert into arr_pk_tbl(pk, f1[0:2147483647]) values (2, '{}');
+ERROR: 54000
+insert into arr_pk_tbl(pk, f1[-2147483648:2147483647]) values (2, '{}');
+ERROR: 54000
-- also exercise the expanded-array case
do $$ declare a int[];
begin
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index 3ad8bdf081a..a4f8299fa98 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -424,6 +424,8 @@ reset enable_bitmapscan;
insert into arr_pk_tbl values(10, '[-2147483648:-2147483647]={1,2}');
update arr_pk_tbl set f1[2147483647] = 42 where pk = 10;
update arr_pk_tbl set f1[2147483646:2147483647] = array[4,2] where pk = 10;
+insert into arr_pk_tbl(pk, f1[0:2147483647]) values (2, '{}');
+insert into arr_pk_tbl(pk, f1[-2147483648:2147483647]) values (2, '{}');
-- also exercise the expanded-array case
do $$ declare a int[];
--
2.39.5