getaddrinfo-is-threadsafe

OpenLDAP upstream conservatively assumes that certain resolver functions
(getaddrinfo, getnameinfo, res_query, dn_expand) are not re-entrant; but we
know that the glibc implementations of these functions are thread-safe, so
we should bypass the use of this mutex.  This fixes a locking problem when
an application uses libldap and libnss-ldap is also used for hosts
resolution.

Closes Debian bug #340601.

Not suitable for forwarding upstream; might be made suitable by adding a
configure-time check for glibc and disabling the mutex only on known
thread-safe implementations.

Gbp-Pq: Name getaddrinfo-is-threadsafe

diff --git a/libraries/libldap/os-ip.c b/libraries/libldap/os-ip.c
index 6c86edd0558e41ec3c489a3a839d30ab18558574..ab6ef49edfacfe83ab895a882c14fddc8185a990 100644 (file)
--- a/libraries/libldap/os-ip.c
+++ b/libraries/libldap/os-ip.c
@@ -645,13 +645,7 @@ ldap_connect_to_host(LDAP *ld, Sockbuf *sb,
        hints.ai_socktype = socktype;
        snprintf(serv, sizeof serv, "%d", port );
 
-       /* most getaddrinfo(3) use non-threadsafe resolver libraries */
-       LDAP_MUTEX_LOCK(&ldap_int_resolv_mutex);
-
        err = getaddrinfo( host, serv, &hints, &res );
-
-       LDAP_MUTEX_UNLOCK(&ldap_int_resolv_mutex);
-
        if ( err != 0 ) {
                Debug1(LDAP_DEBUG_TRACE,
                        "ldap_connect_to_host: getaddrinfo failed: %s\n",

diff --git a/libraries/libldap/util-int.c b/libraries/libldap/util-int.c
index 95bfba96b539958c65533fd61d02094f43f47cf8..5669aa4cb2241df68a88527e553933a653b7c559 100644 (file)
--- a/libraries/libldap/util-int.c
+++ b/libraries/libldap/util-int.c
@@ -487,9 +487,7 @@ int ldap_pvt_get_hname(
        int rc;
 #if defined( HAVE_GETNAMEINFO )
 
-       LDAP_MUTEX_LOCK( &ldap_int_resolv_mutex );
        rc = getnameinfo( sa, len, name, namelen, NULL, 0, 0 );
-       LDAP_MUTEX_UNLOCK( &ldap_int_resolv_mutex );
        if ( rc ) *err = (char *)AC_GAI_STRERROR( rc );
        return rc;