Bug #31088206 "SEGV ON UNKNOWN ADDRESS" PB2 UBSAN ERRORS WITH AUTHENTICATION_LDAP MTR TESTS

The problem was caused by multiple calls to sasl_client_done().
The last call could cause undefined behaviour in some cases.

The server may use SASL both from the auth_ldap_sasl server plugin,
and from the authentication_ldap_sasl_client client plugin.
Server plugins are unloaded before unloading client plugins during
shutdown.

The solution is to *not* call sasl_client_done(), from the server plugin,
or from the client plugin.

Change-Id: Ia7a86834caee65f1ab3e9a85c40db117f4ff0d0e
(cherry picked from commit cda229ebafe730e8b3b4e85fae71342777e20bb7)

Author: Tor Didriksen

libmysql/authentication_ldap/auth_ldap_sasl_client.cc

@@ -209,15 +209,6 @@ Sasl_client::~Sasl_client() {
   m_sasl_mechanism = nullptr;
 }
 
-void Sasl_client::sasl_client_done_wrapper() {
-#if (SASL_VERSION_MAJOR >= 2) && (SASL_VERSION_MINOR >= 1) && \
-    (SASL_VERSION_STEP >= 24) && (!defined __APPLE__) && (!defined __sun)
-  sasl_client_done();
-#else
-  sasl_done();
-#endif
-}
-
 int Sasl_client::send_sasl_request_to_server(const unsigned char *request,
                                              int request_len,
                                              unsigned char **response,
@@ -580,8 +571,6 @@ static int initialize_plugin(char *, size_t, int, va_list) {
 }
 
 static int deinitialize_plugin() {
-  Sasl_client::sasl_client_done_wrapper();
-
   delete g_logger_client;
   g_logger_client = nullptr;
 

libmysql/authentication_ldap/auth_ldap_sasl_client.h

@@ -89,7 +89,6 @@ class Sasl_client {
   int send_sasl_request_to_server(const unsigned char *request, int request_len,
                                   unsigned char **reponse, int *response_len);
   void set_user_info(std::string name, std::string pwd);
-  static void sasl_client_done_wrapper();
   std::string get_method();
 #if defined(KERBEROS_LIB_CONFIGURED)
   void read_kerberos_user_name();

mysql-test/lsan.supp

@@ -35,6 +35,5 @@ leak:ldap_initialize
 
 # sasl_client_init will load all available plugins with _sasl_load_plugins().
 # It seems some of the SASL plugin have leaks.
-# We *do* call sasl_client_done, which calls _sasl_done_with_plugins
 # Both LSAN and Valgrind report leaks.
 leak:sasl_client_add_plugin

mysql-test/valgrind.supp

@@ -797,7 +797,6 @@
 
 # sasl_client_init will load all available plugins with _sasl_load_plugins().
 # It seems some of the SASL plugin have leaks.
-# We *do* call sasl_client_done, which calls _sasl_done_with_plugins
 # Both LSAN and Valgrind report leaks.
 {
    Loading SASL plugins 1
@@ -2469,6 +2468,15 @@
    ...
 }
 
+{
+   LDAP_27
+   Memcheck:Leak
+   match-leak-kinds: reachable
+   fun:malloc
+   ...
+   fun:dlopen@@GLIBC_2.2.5
+}
+
 # Suppress all issues related to libcrypto library
 {
    Conditional jump or move in BN_bin2bn