From 1512078a7a56779d6fdd307a93187b61494de897 Mon Sep 17 00:00:00 2001
From: Nirbhay Choubey <nirbhay@mariadb.com>
Date: Fri, 29 Apr 2016 10:50:39 -0400
Subject: [PATCH] MDEV-9851: CREATE USER w/o IDENTIFIED BY clause causes crash
 when using cracklib plugin

Do not allow NULL password to pass directly to password
validation plugin.
---
 mysql-test/suite/plugins/r/cracklib_password_check.result | 6 ++++++
 mysql-test/suite/plugins/r/simple_password_check.result   | 2 ++
 mysql-test/suite/plugins/t/cracklib_password_check.test   | 8 ++++++++
 mysql-test/suite/plugins/t/simple_password_check.test     | 4 ++++
 sql/sql_acl.cc                                            | 4 +++-
 5 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/mysql-test/suite/plugins/r/cracklib_password_check.result b/mysql-test/suite/plugins/r/cracklib_password_check.result
index 638f138b986..dc31cb6d044 100644
--- a/mysql-test/suite/plugins/r/cracklib_password_check.result
+++ b/mysql-test/suite/plugins/r/cracklib_password_check.result
@@ -39,6 +39,12 @@ Warning	1819	cracklib: it is based on a dictionary word
 Error	1819	Your password does not satisfy the current policy requirements
 grant select on *.* to foobar identified by 'q$%^&*rty';
 drop user foobar;
+#
+# MDEV-9851: CREATE USER w/o IDENTIFIED BY clause causes crash
+# when using cracklib plugin
+#
+create user 'newuser'@'localhost';
+ERROR HY000: Your password does not satisfy the current policy requirements
 uninstall plugin cracklib_password_check;
 create user foo1 identified by 'pwd';
 drop user foo1;
diff --git a/mysql-test/suite/plugins/r/simple_password_check.result b/mysql-test/suite/plugins/r/simple_password_check.result
index c21298cea33..bbb96bb8c38 100644
--- a/mysql-test/suite/plugins/r/simple_password_check.result
+++ b/mysql-test/suite/plugins/r/simple_password_check.result
@@ -72,6 +72,8 @@ READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
 create user foo1 identified by 'pwd';
 ERROR HY000: Your password does not satisfy the current policy requirements
+create user foo1;
+ERROR HY000: Your password does not satisfy the current policy requirements
 grant select on *.* to foo1 identified by 'pwd';
 ERROR HY000: Your password does not satisfy the current policy requirements
 grant select on *.* to `FooBar1!` identified by 'FooBar1!';
diff --git a/mysql-test/suite/plugins/t/cracklib_password_check.test b/mysql-test/suite/plugins/t/cracklib_password_check.test
index d0e05fed926..89b53b656d6 100644
--- a/mysql-test/suite/plugins/t/cracklib_password_check.test
+++ b/mysql-test/suite/plugins/t/cracklib_password_check.test
@@ -30,6 +30,14 @@ show warnings;
 grant select on *.* to foobar identified by 'q$%^&*rty';
 drop user foobar;
 
+--echo #
+--echo # MDEV-9851: CREATE USER w/o IDENTIFIED BY clause causes crash
+--echo # when using cracklib plugin
+--echo #
+
+--error ER_NOT_VALID_PASSWORD
+create user 'newuser'@'localhost';
+
 uninstall plugin cracklib_password_check;
 
 create user foo1 identified by 'pwd';
diff --git a/mysql-test/suite/plugins/t/simple_password_check.test b/mysql-test/suite/plugins/t/simple_password_check.test
index bfe3464f5f9..4965ee492d2 100644
--- a/mysql-test/suite/plugins/t/simple_password_check.test
+++ b/mysql-test/suite/plugins/t/simple_password_check.test
@@ -16,6 +16,10 @@ select * from information_schema.system_variables where variable_name like 'simp
 --error ER_NOT_VALID_PASSWORD
 create user foo1 identified by 'pwd';
 
+# Create user with no password.
+--error ER_NOT_VALID_PASSWORD
+create user foo1;
+
 --error ER_NOT_VALID_PASSWORD
 grant select on *.* to foo1 identified by 'pwd';
 
diff --git a/sql/sql_acl.cc b/sql/sql_acl.cc
index 95b90c263ee..7db7d2cf3fb 100644
--- a/sql/sql_acl.cc
+++ b/sql/sql_acl.cc
@@ -899,7 +899,9 @@ static bool validate_password(LEX_USER *user)
 {
   if (user->pwtext.length || !user->pwhash.length)
   {
-    struct validation_data data= { &user->user, &user->pwtext };
+    struct validation_data data= { &user->user,
+                                   user->pwtext.str ? &user->pwtext :
+                                   const_cast<LEX_STRING *>(&empty_lex_str) };
     if (plugin_foreach(NULL, do_validate,
                        MariaDB_PASSWORD_VALIDATION_PLUGIN, &data))
     {