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 623dfadb280f17ca800aa0b3f75b78cddf5bf2ce..34557726d3f537a9fe62d50f460799c4eb7f4528 100644 (file)
--- a/libraries/libldap/os-ip.c
+++ b/libraries/libldap/os-ip.c
@@ -602,13 +602,7 @@ 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 ) {
                osip_debug(ld, "ldap_connect_to_host: getaddrinfo failed: %s\n",
                        AC_GAI_STRERROR(err), 0, 0);

diff --git a/libraries/libldap/util-int.c b/libraries/libldap/util-int.c
index e65db0c2cdcbdf26b0ec70cf43633dc74b4564c9..319c4503c9d719dcca8ab2a26bf22f05fbf72259 100644 (file)
--- a/libraries/libldap/util-int.c
+++ b/libraries/libldap/util-int.c
@@ -534,9 +534,7 @@ 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;