From b95c40ebf82d095dc476c22e9009273b97102091 Mon Sep 17 00:00:00 2001
From: Oleksandr Byelkin <sanja@mariadb.com>
Date: Fri, 26 Jun 2026 16:30:13 +0200
Subject: [PATCH] MDEV-40159: single quote in DATA DIRECTORY breaks SHOW CREATE
 TABLE

Correct append function called for value in quotes
---
 mysql-test/main/symlink.result | 18 ++++++++++++++++++
 mysql-test/main/symlink.test   | 19 +++++++++++++++++++
 sql/sql_show.cc                |  2 +-
 3 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/mysql-test/main/symlink.result b/mysql-test/main/symlink.result
index 67d067be1f918..f7e06a3f7007b 100644
--- a/mysql-test/main/symlink.result
+++ b/mysql-test/main/symlink.result
@@ -249,3 +249,21 @@ t1	CREATE TABLE `t1` (
   `c3` varchar(100) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci DELAY_KEY_WRITE=1 DATA DIRECTORY='MYSQL_TMP_DIR/' INDEX DIRECTORY='MYSQL_TMP_DIR/'
 drop table t1;
+#
+# MDEV-40159: single quote in DATA DIRECTORY breaks SHOW CREATE TABLE
+#
+CREATE TABLE t1 (a int) data directory="MYSQL_TMP_DIR/o'hara";
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci DATA DIRECTORY='MYSQL_TMP_DIR/o\'hara/'
+DROP TABLE t1;
+CREATE TABLE t1 (a int) index directory="MYSQL_TMP_DIR/o'hara";
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci INDEX DIRECTORY='MYSQL_TMP_DIR/o\'hara/'
+DROP TABLE t1;
+# End of 10.6 tests
diff --git a/mysql-test/main/symlink.test b/mysql-test/main/symlink.test
index d5f52e9a60d86..7a0fe152dbc1c 100644
--- a/mysql-test/main/symlink.test
+++ b/mysql-test/main/symlink.test
@@ -346,3 +346,22 @@ drop table t1;
 #
 # End of 10.1 tests
 #
+
+--echo #
+--echo # MDEV-40159: single quote in DATA DIRECTORY breaks SHOW CREATE TABLE
+--echo #
+
+--mkdir $MYSQL_TMP_DIR/o'hara
+--replace_result $MYSQL_TMP_DIR MYSQL_TMP_DIR
+eval CREATE TABLE t1 (a int) data directory="$MYSQL_TMP_DIR/o'hara";
+--replace_result $MYSQL_TMP_DIR MYSQL_TMP_DIR
+SHOW CREATE TABLE t1;
+DROP TABLE t1;
+--replace_result $MYSQL_TMP_DIR MYSQL_TMP_DIR
+eval CREATE TABLE t1 (a int) index directory="$MYSQL_TMP_DIR/o'hara";
+--replace_result $MYSQL_TMP_DIR MYSQL_TMP_DIR
+SHOW CREATE TABLE t1;
+DROP TABLE t1;
+--rmdir $MYSQL_TMP_DIR/o'hara
+
+--echo # End of 10.6 tests
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index cbfa699e173fc..14c2750d95c7c 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -1684,7 +1684,7 @@ static void append_directory(THD *thd, String *packet, LEX_CSTRING *dir_type,
     }
     filename= winfilename;
 #endif
-    packet->append(filename, length);
+    packet->append_for_single_quote(filename, length);
     packet->append('\'');
   }
 }