Bug #24619222: PASSWORD_LIFETIME IS RESET TO NULL WHEN USER

               EXECUTES ALTER USER STATEMENT.

Analysis:- The "password_lifetime" value is set to NULL for
certain set of statements.

Fix:- A check is introduced before resetting the
password_lifetime value to NULL.

Author: Arun Kuruvila

mysql-test/r/grant_user_lock_qa.result

@@ -425,7 +425,7 @@ plugin	mysql_native_password
 authentication_string	#
 ssl_type	X509
 password_expired	N
-password_lifetime	NULL
+password_lifetime	0
 account_locked	N
 
 SHOW CREATE USER u6@localhost;
@@ -543,7 +543,7 @@ ssl_cipher
 x509_issuer	
 x509_subject	/C=SE/ST=Stockholm/L=Stockholm/O=Oracle/OU=MySQL/CN=Client
 password_expired	N
-password_lifetime	NULL
+password_lifetime	0
 account_locked	N
 
 SHOW CREATE USER u9@localhost;

mysql-test/suite/binlog/r/binlog_grant_alter_user.result

@@ -428,7 +428,7 @@ plugin	mysql_native_password
 authentication_string	#
 password_expired	N
 password_last_changed	#
-password_lifetime	NULL
+password_lifetime	0
 ALTER USER u3@localhost
 REQUIRE SUBJECT '/C=SE/ST=Stockholm/L=Stockholm/O=Oracle/OU=MySQL/CN=Client'
            WITH MAX_QUERIES_PER_HOUR 2 MAX_USER_CONNECTIONS 2
@@ -535,7 +535,7 @@ plugin	mysql_native_password
 authentication_string	#
 password_expired	N
 password_last_changed	#
-password_lifetime	NULL
+password_lifetime	80
 CREATE USER u7@localhost IDENTIFIED WITH 'mysql_native_password'
             BY 'auth_string' REQUIRE CIPHER 'DHE-RSA-AES256-SHA';
 SELECT user,ssl_type,ssl_cipher,x509_issuer,x509_subject,

sql/auth/sql_user.cc

@@ -458,7 +458,8 @@ bool set_and_validate_user_attributes(THD *thd,
         always check for password expire/interval attributes as there is no
         way to differentiate NEVER EXPIRE and EXPIRE DEFAULT scenario
       */
-      what_to_set|= PASSWORD_EXPIRE_ATTR;
+      if (Str->alter_status.update_password_expired_fields)
+        what_to_set|= PASSWORD_EXPIRE_ATTR;
     }
     else
     {