ITS#7968 add locks for syncrepl cookiestate

Mutex must be held even for a read-access of a cookie state,
as there may be a race with write in other thread.

diff --git a/servers/slapd/syncrepl.c b/servers/slapd/syncrepl.c
index caab9f58eda15c181bf800949bd48640446470c1..6ad8dc5943308a18ac3016e1b40c3a897c2b0c04 100644 (file)
--- a/servers/slapd/syncrepl.c
+++ b/servers/slapd/syncrepl.c
@@ -926,6 +926,7 @@ do_syncrep2(
                                        if ( syncCookie.ctxcsn ) {
                                                int i, sid = slap_parse_csn_sid( syncCookie.ctxcsn );
                                                check_syncprov( op, si );
+                                               ldap_pvt_thread_mutex_lock( &si->si_cookieState->cs_mutex );
                                                for ( i =0; i<si->si_cookieState->cs_num; i++ ) {
                                                        /* new SID */
                                                        if ( sid < si->si_cookieState->cs_sids[i] )
@@ -935,15 +936,18 @@ do_syncrep2(
                                                                        bdn.bv_val[bdn.bv_len] = '\0';
                                                                        Debug( LDAP_DEBUG_SYNC, "do_syncrep2: %s CSN too old, ignoring %s (%s)\n",
                                                                                si->si_ridtxt, syncCookie.ctxcsn->bv_val, bdn.bv_val );
+                                                                       si->si_too_old = 1;
+                                                                       ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_mutex );
                                                                        ldap_controls_free( rctrls );
                                                                        rc = 0;
-                                                                       si->si_too_old = 1;
                                                                        goto done;
                                                                }
                                                                si->si_too_old = 0;
                                                                break;
                                                        }
                                                }
+                                               ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_mutex );
+
                                                /* check pending CSNs too */
                                                while ( ldap_pvt_thread_mutex_trylock( &si->si_cookieState->cs_pmutex )) {
                                                        if ( slapd_shutdown ) {
@@ -953,17 +957,18 @@ do_syncrep2(
                                                        if ( !ldap_pvt_thread_pool_pausecheck( &connection_pool ))
                                                                ldap_pvt_thread_yield();
                                                }
+
                                                for ( i =0; i<si->si_cookieState->cs_pnum; i++ ) {
                                                        if ( sid < si->si_cookieState->cs_psids[i] )
                                                                break;
                                                        if ( si->si_cookieState->cs_psids[i] == sid ) {
                                                                if ( ber_bvcmp( syncCookie.ctxcsn, &si->si_cookieState->cs_pvals[i] ) <= 0 ) {
+                                                                       ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_pmutex );
                                                                        bdn.bv_val[bdn.bv_len] = '\0';
                                                                        Debug( LDAP_DEBUG_SYNC, "do_syncrep2: %s CSN pending, ignoring %s (%s)\n",
                                                                                si->si_ridtxt, syncCookie.ctxcsn->bv_val, bdn.bv_val );
                                                                        ldap_controls_free( rctrls );
                                                                        rc = 0;
-                                                                       ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_pmutex );
                                                                        goto done;
                                                                }
                                                                ber_bvreplace( &si->si_cookieState->cs_pvals[i],
@@ -1032,6 +1037,7 @@ do_syncrep2(
                                /* on failure, revert pending CSN */
                                if ( rc != LDAP_SUCCESS ) {
                                        int i;
+                                       ldap_pvt_thread_mutex_lock( &si->si_cookieState->cs_mutex );
                                        for ( i = 0; i<si->si_cookieState->cs_num; i++ ) {
                                                if ( si->si_cookieState->cs_sids[i] == si->si_cookieState->cs_psids[punlock] ) {
                                                        ber_bvreplace( &si->si_cookieState->cs_pvals[punlock],
@@ -1041,6 +1047,7 @@ do_syncrep2(
                                        }
                                        if ( i == si->si_cookieState->cs_num )
                                                si->si_cookieState->cs_pvals[punlock].bv_val[0] = '\0';
+                                       ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_mutex );
                                }
                                ldap_pvt_thread_mutex_unlock( &si->si_cookieState->cs_pmutex );
                        }