From 63c82c0ed7b29dc839e076d5b3efb373f04a2627 Mon Sep 17 00:00:00 2001 From: Ryan Tandy Date: Tue, 27 Aug 2019 17:58:44 -0700 Subject: [PATCH] ITS#9069 Do not call gnutls_global_set_mutex() Since GnuTLS moved to implicit initialization on library load, calling this function deinitializes GnuTLS and then re-initializes it. When GnuTLS uses /dev/urandom as an entropy source (getrandom() not available, or older versions of GnuTLS), and the application closed all file descriptors at startup, this could result in GnuTLS opening /dev/urandom over one of the application's file descriptors when re-initialized. Additionally, the custom mutex functions are never reset, so if libldap is unloaded (for example via dlclose()) after calling this, its code may be unmapped and the application could crash when GnuTLS calls the mutex functions. On typical systems, GnuTLS system mutexes are probably the same as what libldap uses anyway. --- libraries/libldap/tls_g.c | 43 +-------------------------------------- 1 file changed, 1 insertion(+), 42 deletions(-) diff --git a/libraries/libldap/tls_g.c b/libraries/libldap/tls_g.c index 1baf2b883c..6f5bd12e61 100644 --- a/libraries/libldap/tls_g.c +++ b/libraries/libldap/tls_g.c @@ -69,51 +69,10 @@ static int tlsg_cert_verify( tlsg_session *s ); #ifdef LDAP_R_COMPILE -static int -tlsg_mutex_init( void **priv ) -{ - int err = 0; - ldap_pvt_thread_mutex_t *lock = LDAP_MALLOC( sizeof( ldap_pvt_thread_mutex_t )); - - if ( !lock ) - err = ENOMEM; - if ( !err ) { - err = ldap_pvt_thread_mutex_init( lock ); - if ( err ) - LDAP_FREE( lock ); - else - *priv = lock; - } - return err; -} - -static int -tlsg_mutex_destroy( void **lock ) -{ - int err = ldap_pvt_thread_mutex_destroy( *lock ); - LDAP_FREE( *lock ); - return err; -} - -static int -tlsg_mutex_lock( void **lock ) -{ - return ldap_pvt_thread_mutex_lock( *lock ); -} - -static int -tlsg_mutex_unlock( void **lock ) -{ - return ldap_pvt_thread_mutex_unlock( *lock ); -} - static void tlsg_thr_init( void ) { - gnutls_global_set_mutex (tlsg_mutex_init, - tlsg_mutex_destroy, - tlsg_mutex_lock, - tlsg_mutex_unlock); + /* do nothing */ } #endif /* LDAP_R_COMPILE */