From: Michael Paquier <michael@paquier.xyz>
Date: Wed, 13 May 2026 05:43:42 +0000 (+0900)
Subject: Add more tests for corrupted data with pglz_decompress()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=900c07b854a7d7549ea4116aaafbb02bc610553a;p=thirdparty%2Fpostgresql.git

Add more tests for corrupted data with pglz_decompress()

Two cases fixed by 2b5ba2a0a141 were not covered, to emulate the
handling of corrupted data, for:
- set control bit with a valid 2-byte match tag where offset is 0.
- set control bit with a valid 2-byte match tag where offset exceeds
output written.

Oversight in 67d318e70402.

Reviewed-by: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Discussion: https://postgr.es/m/agF4xkIdRcrCIprs@paquier.xyz
Backpatch-through: 14
---

diff --git a/src/test/regress/expected/compression_pglz.out b/src/test/regress/expected/compression_pglz.out
index 0ef49d42506..066a3317c65 100644
--- a/src/test/regress/expected/compression_pglz.out
+++ b/src/test/regress/expected/compression_pglz.out
@@ -60,6 +60,18 @@ SELECT test_pglz_decompress('\x010f01'::bytea, 1024, false);
 ERROR:  pglz_decompress failed
 SELECT test_pglz_decompress('\x010f01'::bytea, 1024, true);
 ERROR:  pglz_decompress failed
+-- Corrupted compressed data.  Set control bit with a valid 2-byte match
+-- tag where offset exceeds output written.
+SELECT test_pglz_decompress('\x011001'::bytea, 1024, false);
+ERROR:  pglz_decompress failed
+SELECT test_pglz_decompress('\x011001'::bytea, 1024, true);
+ERROR:  pglz_decompress failed
+-- Corrupted compressed data.  Set control bit with a valid 2-byte match
+-- tag where offset is 0.
+SELECT test_pglz_decompress('\x010300'::bytea, 1024, false);
+ERROR:  pglz_decompress failed
+SELECT test_pglz_decompress('\x010300'::bytea, 1024, true);
+ERROR:  pglz_decompress failed
 -- Clean up
 DROP FUNCTION test_pglz_compress;
 DROP FUNCTION test_pglz_decompress;
diff --git a/src/test/regress/sql/compression_pglz.sql b/src/test/regress/sql/compression_pglz.sql
index a44af02afb7..dbd37f7d4eb 100644
--- a/src/test/regress/sql/compression_pglz.sql
+++ b/src/test/regress/sql/compression_pglz.sql
@@ -48,6 +48,16 @@ SELECT test_pglz_decompress('\x01ff'::bytea, 1024, true);
 SELECT test_pglz_decompress('\x010f01'::bytea, 1024, false);
 SELECT test_pglz_decompress('\x010f01'::bytea, 1024, true);
 
+-- Corrupted compressed data.  Set control bit with a valid 2-byte match
+-- tag where offset exceeds output written.
+SELECT test_pglz_decompress('\x011001'::bytea, 1024, false);
+SELECT test_pglz_decompress('\x011001'::bytea, 1024, true);
+
+-- Corrupted compressed data.  Set control bit with a valid 2-byte match
+-- tag where offset is 0.
+SELECT test_pglz_decompress('\x010300'::bytea, 1024, false);
+SELECT test_pglz_decompress('\x010300'::bytea, 1024, true);
+
 -- Clean up
 DROP FUNCTION test_pglz_compress;
 DROP FUNCTION test_pglz_decompress;