ITS#5405 fix race condition

diff --git a/servers/slapd/overlays/syncprov.c b/servers/slapd/overlays/syncprov.c
index ad8b9bb329e0b507e54f8dbaf4833156c4058aeb..ae0297bf4deb080f2d51a15db8b5d9ce49440d13 100644 (file)
--- a/servers/slapd/overlays/syncprov.c
+++ b/servers/slapd/overlays/syncprov.c
@@ -853,10 +853,10 @@ syncprov_qplay( Operation *op, slap_overinst *on, syncops *so )
                        so->s_res = sr->s_next;
                if ( !so->s_res )
                        so->s_restail = NULL;
-               ldap_pvt_thread_mutex_unlock( &so->s_mutex );
-
+               /* Exit loop with mutex held */
                if ( !sr || so->s_op->o_abandon )
                        break;
+               ldap_pvt_thread_mutex_unlock( &so->s_mutex );
 
                opc.sdn = sr->s_dn;
                opc.sndn = sr->s_ndn;
@@ -883,9 +883,24 @@ syncprov_qplay( Operation *op, slap_overinst *on, syncops *so )
 
                ch_free( sr );
 
-               if ( rc )
+               if ( rc ) {
+                       /* Exit loop with mutex held */
+                       ldap_pvt_thread_mutex_lock( &so->s_mutex );
                        break;
+               }
+       }
+
+       /* wait until we get explicitly scheduled again */
+       ldap_pvt_thread_mutex_lock( &slapd_rq.rq_mutex );
+       ldap_pvt_runqueue_stoptask( &slapd_rq, rtask );
+       if ( rc == 0 ) {
+               ldap_pvt_runqueue_resched( &slapd_rq, rtask, 1 );
+       } else {
+               /* bail out on any error */
+               ldap_pvt_runqueue_remove( &slapd_rq, rtask );
        }
+       ldap_pvt_thread_mutex_unlock( &slapd_rq.rq_mutex );
+       ldap_pvt_thread_mutex_unlock( &so->s_mutex );
        return rc;
 }
 
@@ -925,17 +940,6 @@ syncprov_qtask( void *ctx, void *arg )
        /* decrement use count... */
        syncprov_free_syncop( so );
 
-       /* wait until we get explicitly scheduled again */
-       ldap_pvt_thread_mutex_lock( &slapd_rq.rq_mutex );
-       ldap_pvt_runqueue_stoptask( &slapd_rq, rtask );
-       if ( rc == 0 ) {
-               ldap_pvt_runqueue_resched( &slapd_rq, rtask, 1 );
-       } else {
-               /* bail out on any error */
-               ldap_pvt_runqueue_remove( &slapd_rq, rtask );
-       }
-       ldap_pvt_thread_mutex_unlock( &slapd_rq.rq_mutex );
-
 #if 0  /* FIXME: connection_close isn't exported from slapd.
                 * should it be?
                 */